Along with the government's policy to convert from kerosene to LPG gas, LPG consumer demand is increasing. It requires the LPG distributors to be able to meet the needs of its customers. PT. Limas Raga Inti is an authorized distributor company PT. Pertamina LPG product devoted to distribute 12 kg. The company's main commitment is to provide the best service to the consumer. One of the efforts to improve the quality of service is to provide optimization of the distribution process. Optimization can be done by determining the distribution of the matrix saving method to obtain the optimal route. The purpose of the optimization of route determination is to provide effectiveness and efficiency of the distribution process. Effectiveness and efficiency can be seen with the speed of delivery time and can overcome the problems that exist in the company. In the process of determining the route to saving matrix, is done in the consumer sorting method which has produced the nearest neighbor and nearest the insert. Then do the repair method using 2-opt and or-opt in order to provide the best route to the selected proposal. Furthermore, the delivery time will be calculated based on the productivity of the proposal and indicating the optimal route. The results of this study are are 4 routes proposed by sorting nearest neighbor method with a total delivery time of 10 hours 30 minutes for 100 customers spread in the distribution area D14. The resulting productivity by 85.11%.

This paper analyses the start of the debt crisis in Europe and in Spain, which increased inflation, unemployment and public debt. Although Spanish banking system was considered one of the best, the growing debt brought Spain into one of the worst affected countries in financial crisis. Because of this, Spain was faced to the fiscal consolidation as the imperative for further development. The strength of the crisis in Spain can be seen from main economic indicators. Budget deficit in Spain was almost 12% just two years after it went into surplus for the first time in 30 year period. Public debt has started to rise from 2007 and in 2013 it overcomes 90% of GDP. The rate of unemployment also started to rise from 2007 and in 2013 it is higher than 25%. This paper analyses also Phillips curve in Spain using the actual data after the start of fiscal consolidation.

The aim of this paper is to examine the return and volatility spillovers and stock market co-movements among Western, Central and Southeast European stock markets. To examine the volatility spillover effects we employ a multivariate GARCH-BEKK (1, 1) model on a daily data from 2005 to 2014. There is a high and stable conditional correlation between Central and Western European markets during most of the analyzed period and the conditional correlation rises sharply during the periods of financial turmoil, suggesting some evidence on contagion. Conditional correlation between Croatian and Romanian markets and their Western counterparts is modest but it increases during the periods of financial crisis. Conditional correlation coefficients indicate that Macedonian and Serbian stock markets are relatively isolated from the advanced European markets. The return spillovers are investigated with the forecast-error variance decomposition based on the generalized VAR model. Following Diebold and Yilmaz (2012), we develop “spillover indices” based on the variance decomposition results on the generalized VAR model. The results indicate that total spillover index rose sharply during the periods of major financial disruptions. DAX and FTSE100 are the major net transmitters of spillovers to Central and Southeast European markets. There are bi-directional spillovers between DAX and FTSE100, between PX and WIG-20 and between MBI10 and BELEX15.

Sustainable development is a knowledge intensive process, but plagued by persistent concerns over our apparent inability to connect what we know with more sustainable practices and outcomes. While considerable attention has been given to ways we may better understand and enhance the knowledge-based processes that support the governance of social-ecological systems, relatively few have examined the governance of knowledge itself. The institutions-rules and norms-that govern knowledge may shed light on the persistence of 'gaps' between knowledge and action. In this review I seek to answer the question: can interdisciplinary knowledge governance literature contribute to understanding and analysing the institutional knowledge-based dimensions of sustainable development? I present and analyse the concept of knowledge governance as it is emerging in a range of disciplines and practice areas, including private sector management literature and public regulation theory and practice. I then integrate the findings from this review into a model of sustainable development proposed by Nilsson et al. [1]. I show that knowledge governance (as a scale above knowledge management) can inform Nilsson et al.'s three "nested" dimensions of sustainability: human wellbeing (through access to knowledge and freedom to exercise informed choice); resourcebase management (though enhancing regulation and innovation and transitions from exclusive to inclusive knowledge systems); and global public goods (by balancing public and private interests and fostering global innovation systems). This review concludes by presenting a framework that places sustainable development in the context of broader socio-political struggles towards more open, inclusive knowledge systems.

Disaster losses continue to escalate globally and in many regions human losses (death, injury, permanent displacement) often exceed the economic toll. Current disaster policies are reactive with a short-term focus―respond and rebuild as quickly as possible and in the same way after the event. Such policies ignore the longer-term approach of building disaster-resilient communities, in which investments made now show financial and social returns later by reducing the impact of disasters. This article provides a vision for resilient nations in 2030 based on three recent policy reports. It highlights the necessary steps towards achieving sustainability using the lens of disaster resilience as the pathway towards strengthening communities' ability to prepare and plan for, absorb, respond to, and recover from present and future disasters.

An estimated 2.6 billion people rely on traditional biomass for home cooking and heating, so improving the efficiency of household cookstoves could provide significant environmental, social and economic benefits. Some researchers have estimated that potential greenhouse gas emission reductions could exceed 1 billion tons of carbon dioxide equivalent $\left(\mathrm{CO}_2 \mathrm{e}\right)$ per year. Carbon finance offers a policy mechanism for realizing some of this potential and could also bring improved monitoring to cookstove projects. However, there are formidable methodological challenges in estimating emission reductions. This paper evaluates the quantification approaches to three key variables in calculating emission impacts: biomass fuel consumption, fraction of non-renewable biomass, and emission factors for fuel consumption. It draws on a literature review as well as on interviews with technical experts and market actors, and identifies lessons learned and knowledge gaps. Key research needs identified include incorporating accounting for uncertainty; development of additional default factors for biomass consumption for baseline stoves; refinement of monitoring approaches for cookstove use; broadened scope of emission factors used for cookstoves; accounting for non- $\mathrm{CO}_2$ gases and black carbon; and refinement of estimates and approaches to considering emissions from bioenergy use across methodologies.

The dominant paradigm of sustainable development (SD) where the environment is just the third pillar of SD has proven inadequate to keep humanity within the safe operational space determined by biophysical planetary boundaries. This implies the need for a revised definition compatible with a nested model of sustainable development, where humanity forms part of the overall social-ecological system, and that would allow more effective sustainable development goals and indicators. In this paper an alternative definition is proposed based on the thermodynamics of open systems applied to ecosystems and human systems. Both sub-systems of the global social-ecological system show in common an increased capability of buffering against disturbances as a consequence of an internal increase of order. Sustainable development is considered an optimization exercise at different scales in time and space based on monitoring the change in the exergy content and exergy dissipation of these two sub-systems of the social-ecological system. In common language it is the increase of human prosperity and well-being without loss of the structure and functioning of the ecosystem. This definition is functional as it allows the straightforward selection of quantitative indicators, discerning sustainable development from unsustainable development, unsustainable stagnation and sustainable retreat. The paper shows that the new definition is compatible with state of the art thinking on ecosystem services, the existence of regime shifts and societal transitions, and resilience. One of the largest challenges in applying the definition is our insufficient understanding of the change in ecosystem structure and function as an endpoint indicator of human action, and its effect on human prosperity and well-being. This implies the continued need to use midpoint indicators of human impact and related thresholds defining the safe operating space of the present generation with respect to future generations. The proposed definition can be considered a valuable complement to the recently emerged nested system discourse of sustainable development, by offering a more quantitative tool to monitor and guide the transition of human society towards a harmonious relationship with the rest of the biosphere.

A lot can be learned from the numerous pitfalls of sustainable development implementation: they outline how collective representation, short term interests and balance of power can undermine sustainability. For instance, the usefulness of global institutions in dealing with sustainable development is questionable as most are skewed toward the interests and perceptions of developed countries. The notion of sustainable development itself induces a profound cleavage between academic authors and the actors of its implementation, some of whom confuse it with sustainable growth (which favors spatial equity), whilst the others with environment management (which favors intergenerational equity). This polarization is a real problem, since originally, "Our Common Future" report promotes an inclusive approach, able to cope with both equities simultaneously. Finally, if there are obligations toward future generations, there are also obligations toward the current generation. The key issue for effective sustainability policies should be making them acceptable to everyone by including the expectations of local societies and communities. As a matter of consequence, universal solutions do not exist. They would not meet the specificities of local circumstances. The traditional prescriptive sustainable development model should give way to flexible plural sustainabilities. Singular, top-down, global-to-local approaches to sustainable development should be substituted for multiple sustainabilities.

I am honored to contribute an editorial for the inaugural issue of Challenges in Sustainability (CiS). It has provided the opportunity for me to take a step back and reflect on both the developmental progress in the field of sustainability science since its formal launch, now over twelve years ago [1], [2], and where the field might head in coming years. While it may always feel that the field is changing too slowly to keep up with the challenges it addresses, the developments have been noteworthy, especially in academia. I will discuss three areas: education, research and institutional development.

The growing offering of sustainability (science) educational programs at all levels has been an important part of the field’s evolution. Individual areas of concentration can include business and management, leadership, engineering, or policy management, to name a few. Flagship programs are now found throughout the world, including Arizona State University, Leuphana University of Lüneburg, and the University of Tokyo. In addition, programs at smaller academic institutions such as Furman and Kean Universities in the U.S. have arisen to meet the increasing demand for sustainability education. In Sweden, where I am based, there are international master’s programs in sustainability at Uppsala, Stockholm, Malmö, and Lund Universities, as well as Blekinge Institute of Technology. These programs and their different foci, seek not only to increase student knowledge to understand the complexities of sustainability challenges, but also aim to strengthen key competency development [3] in areas such as facilitation and strategic leadership.

In addition to sustainability education, the nature of research projects and programs in the field has also changed. The changes have been driven by both top-down funding priorities to finance research that is more relevant to society, and bottom-up desire from scholars to carry out more integrated work. This has led to the slow evolution from a focus on descriptive analytical research, with emphases on understanding the effects of environmental change, to transitional (or transformational) research agendas that embrace working in closer collaboration with societal stake-holders. Such research may concentrate on, for example, envisioning and scenario exercises, or problem-solving strategies beyond change strict policy change [4], [5]. Transitional sustainability science research is being carried out by individuals in innovative Ph.D. projects focused on single case studies using particular theories and approaches, and by networks of researchers in longer-term programs, such as the Earth System Governance project (www.earthsystem governance.org), united by common sustainable development themes.

To operationalize the education and research agendas in sustainability science, new organizational constellations have developed. Changes have ranged from the creation of new faculty structures at a number of universities, to the establishment of interdisciplinary research schools and programs. The Lund University Centre of Excellence for Integration of Social and Natural Dimensions of Sustainability (www.lucid.lu.se) is just one example of a longer-term program that unites senior and junior staff and Ph.D. candidates from disciplinary backgroundsincluding Economics and Economic History, Philosophy, Physical Geography, Human Geography, Political Science, and Human Ecology. The frequent interactions via discussions, debates, and joint publications have the goal of, amongst others, fostering new professionals who are capable of and accept working with the theoretical and empirical multiplicities [6] often inherent in sustainability education and research.

Despite the advancements over the past decade, there is still much to be done. Continued creativity in restructuring academic disciplines, departments, and funding and tenure incentives are necessary to pro- mote the interaction needed to achieve the interdisciplinary goals of sustainability science. Sustainability issues must also be strengthened in other areas such as the arts and humanities utilizing alternative forms of knowledge dissemination. In the area of education, additional sustainability programs are still needed,but more importantly, there must also be increased efforts in mainstreaming sustainability into all educational programs at different levels. Finally, the field must also continue to place strong emphases on reaching outside of academia in addressing pressing societal challenges.

The launch of Challenges in Sustainability represents an important step in further strengthening the field. The journal’s broad aims that focus on systemic analyses of sustainability challenges, solutions and transition processes, and associated trade-offs within socio-ecological systems, will create an important publishing outlet for scholars involved in integrative research. Furthermore, because Challenges in Sustainability is open access, it will mean that the knowledge produced in it can reach a wider range of stake-holders, adding one more attribute in a sustainability science we want to create.

Measuring sustainable development based on analytical models of growth and development and modern methods of growth accounting is an economic approach—often called the capital approach – to establishing sustainable development indicators (SDIs). Ecological approaches may be combined with the capital approach, but there are also other approaches to establishing sustainable development indicators—for example the so-called integrated approach. A recent survey of the various approaches is provided in UNECE, OECD and Eurostat [1]. This review note is not intended to be another survey of the various approaches. Rather the objective of this paper is twofold: to present an update on an economic approach to measuring sustainable development—the capital approach—and how this approach may be combined with the ecological approach; to show how this approach is actually used as a basis for longer-term policies to enhance sustainable development in Norway—a country that relies heavily on non-renewable natural resources. We give a brief review of recent literature and set out a model of development based on produced, human, natural and social capital, and the level of technology. Natural capital is divided into two parts—natural capital produced and sold in markets (oil and gas)—and non-market natural capital such as clean air and biodiversity. Weak sustainable development is defined as non-declining welfare per capita if the total stock of a nation's capital is maintained. Strong sustainable development is if none of the capital stocks, notably non-market natural capital, is reduced below critical or irreversible levels. Within such a framework, and based on Norwegian experience and statistical work, monetary indexes of national wealth and its individual components including real capital, human capital and market natural capital are presented. Limits to this framework and to these calculations are then discussed, and we argue that such monetary indexes should be sustainable development indicators (SDIs) of non-market natural capital, and physical SDIs, health capital and social capital. Thus we agree with the Stiglitz-Sen-Fitoussi Commission [2] that monetary indexes of capital should be combined with physical SDIs of capital that have no market prices. We then illustrate the policy relevance of this framework, and how it is actually being used in long term policy making in Norway—a country that relies heavily on non-renewable resources like oil and gas. A key sustainability rule for Norwegian policies is to maintain the total future capital stocks per capita in real terms as the country draws down its stocks of non-renewable natural capital —applying a fiscal guideline akin to the Hartwick rule.

Sustainability science is a young discipline that started emerging in the late 20th century, although Hans Carl von Carlowitz had already introduced ideas about sustainable management of forests in the early 18 th century. In recent times, the Club of Rome report in 1972 and the Brundtland report in 1987 developed these concepts further, and subsequently the sustainability idea became prominent in political debates as well. In both reports it was recognized that growth would have certain limits and a different style of resource utilization was therefore necessary. However, despite numerous approaches dealing with sustainability, it is still an important issue.

Nowadays humanity increasingly interferes with natural systems on a planetary scale. This holds for many subsystems of the Earth including the climate, soil and water bodies, and marine systems. During the 20th century, rapid technological development and demographic pressure advanced to a degree that we caused radical and unintended changes in the Earth's integrity. This is observable in certain subsystems, for example in the atmosphere (global warming), in marine systems (overexploitation of fish stocks), or in soils (degradation). One crucial element of sustainability is the capacity of natural resources to sustain human demands. It is foreseeable that parts of the system are overburdened beyond their capacity. This holds likewise for waste disposal, as for the atmosphere (greenhouse gases) and the utilization of resources like ores and renewables like trees and fish. To sum up, one can state that the overexploitation of natural resources and economic growth causes environmental impacts which may lead several systems to the brink of collapse. In other words, humanity causes a multitude of problems and most of them are not grounded in one sector, region, either can they be described by one scientific discipline.

Thus, sustainability science is a discipline that can be placed as the one at the meeting point of different scientific disciplines. However, during the last four decades, science made remarkable progress in regard to an assessment on how climate and global change will affect livelihood conditions, and how humanity is accelerating the above mentioned changes. The question is how we can avoid certain human activities that destroy the functionality of certain subsystems of the Earth and how we can develop potential solutions. It is a major challenge to understand the dynamics of man-made environment systems as a basis for the development of sustainable transition pathways in the sense of planetary engineering and management. In other words, sustainability science addresses the man-made environment interface.

Although all these points have bleen well-known for decades, we need to ask why it is so difficult to achieve pathbreaking scientific results, which may help us to develop clear visions of real sustainable development. It is well-known that resource consumption is an accompanying factor of economic prosperity and global resource consumption is still steeply growing. In some countries we observe-mainly the advanced ones-that resource consumption stabilizes or even decreases, while their high material intensity is still managed by exporting it to developing countries. Thus, the challenge to decouple resource consumption from economic development remains, and it is not only a question of a green economy, technological progress, or how natural resources are being utilized. It is indeed also a societal challenge. Human lifestyle changes might be a further catalyst for making headway towards sustainability. Nevertheless, current progress into this direction is slow, moreover, in large parts in the developing countries, we can see a tendency just to copy westernized lifestyles. A real innovation for the world would be a strategic approach for a sustainable economy that results in social equity and fairness, risk resilient livelihood conditions, sustainable resource use, and the avoidance of ecological scarcities-all these under consideration of planetary boundaries.

Nevertheless, sustainability is still an elusive concept. It is hard to define what sustainability really implies in terms of environmental constraints or societal development, in particular on a regional scale. Consequently, at the beginning of the 21st century, scientific bodies called for a more systematic sustainability science, e.g. International Council for Science defined sustainability as a major goal in its research strategies. Despite these efforts, concepts still lack real meaning. Thus, the aim should be to underpin activities dealing with the general aspects of sustainability with stronger and sounder scientific concepts. Questions, like: what exactly is sustainability? How can we achieve sustainability targets? And, what does 'being sustainable' mean? need to be in the foreground. Thus, sustainability science is environmental systems science.

Although all these points have been intensely discussed in recent decades, a thrilling and demanding journey still lies ahead for sustainability science. In regard to methodological terms, we need to encompass the different magnitudes of scales in terms of time, space and functions. Thus, sustainability science still invokes a lot of questions, i.e. we have to tackle, in particular, the following three challenges: 1) The provision of a methodological arsenal that allows the description and analysis of questions of sustainability in a comparable and transferable manner, i.e. we permanently have to ask ourselves what we can learn from singular cases in terms of the overarching sustainability challenge; 2) Options for solutions at different levels, e.g. regional and global, need to be assessed systematically in order to develop pathways which allow us to achieve predefined environmental targets, like the 2℃ target agreed in the Copenhagen Accord 2009; 3) As a lot of strategies are included under the term 'sustainability', there is a need to develop a concept which allows assessment and measurement of success of implemented sustainability measures.

However, sustainability itself is a challenge, because it needs ethical decisions from humankind itself whether we want to live in a safe environment or not. But how we achieve these safe limits is an issue of sustainability science, i.e. in terms of how to achieve these limits and what potential trade-offs there might be. The new journal Challenges in Sustainability provides a perfect platform for these goals.

Nowadays, a variety of numerical methods and numerical formulations exits to solve complex or coupled field problems in three dimensions. Most of them are generally applicable to nearly arbitrary kind of field problems. On the other hand, some highly optimized methods are available, which are predestined for the solution of a specific kind of problem. Especially in the case of weakly coupled multiphysics problems, a mixture of several numerical methods is very advantages to benefit from different properties of numerical methods for diverse physical sub-problems. A very promising approach for a flexible coordination of the related solution process is the application of software agents. Then, the results of one sub-problem are converted into boundary values or volume source distributions for another sub-problem and software agents choose solution methods independently for each sub-problem. Furthermore, two main aspects have to be considered in applications of numerical methods. First, the solution of a boundary value problem should be computed efficiently and second, the solution is evaluated for visualization and interpretation of obtained results. In practice, it is difficult to choose a single appropriate method, which is well suited both for the solution of a problem and its evaluation, since the demands differ in both cases. Here, a concept is presented to apply various numerical methods successfully to the solution and evaluation of complex field problems. Attention is mainly turned on the integration of boundary element methods into the concept of mixed numerical formulations.

Climate change impacts particularly affect vulnerable populations such as children. Therefore, addressing the adaptation of educational buildings is crucial in avoiding these negative effects on school performance. In this paper, three educational buildings, located in Badajoz (Spain), Evora (Portugal) and Porto (Portugal), serve as pilot samples to study the suitability of nature-based solutions (NBS), chosen for each one of three climatic zones. The NBS selected include green roofs, vertical structures with vegetation to shade holes, outdoor trees and free-cooling ventilation. The scenarios of the different NBS implemented in the three models were simulated with the software EnergyPlus, which allows optimising the appropriate decision before renovation operations begin. The results obtained from the simulations suggest energy performance improvements after applying the most adequate NBS selection to each one of the three buildings tested. Particularly, a reduction in radiation on both roofs and facades is required in the case of Evora and Badajoz, where both climate zones have similar features, that is, warm and dry. While in Porto, milder and more humid than the former ones, it is very effective to operate mainly on the roof, complemented by small ventilation operations.

In drive systems and component technology a high reliability is very important for machines. Machine element dimensions are calculated for reliability. The properties for these elements are based on conventional manufacturing techniques. Very high stresses are applied on bearings in their operating time. To improve the endurance life, residual stresses can be induced into the subsurface zone. In contrast to a conventional grinding process, the mechanical surface modification process deep rolling is able to induce very high compressive residual stresses. A computational approach was developed to establish an appropriate residual stress depth profile matching the applied loads. Thus, the costs of manufacturing can be chosen in accordance to the required properties. The method to determine the residual stresses is based on an iterative reverse calculation of an existing bearing fatigue life model of Ioannides et al. The model originates from the approach of Lundberg and Palmgren (1947) including a stress fatigue limit tu. For the term ti, the fatigue criterion of Dang-Van is applied. The equation accounts for the maximum orthogonal shear stress and the local hydrostatic pressure phyd, corrected for residual and hoop stress. The inputs into the computational model are the stresses on the surface, which are simulated based on the load and geometry of the contact between roller and bearing surface. As an output the required residual stress profile underneath the bearings raceway is given to achieve a bearing fatigue life as required for the given application. In order to verify the model, the bearing fatigue life was experimentally determined for a given residual stress profile by experiments.

The paper discusses research that concerns itself with the design explorations of high performance structural and climatic systems. It also examines their efficient and low-cost application techniques in refugee facilities. Initially, the paper presents a survey of the current conditions of refugee schools in Lebanon. The survey highlights the need for alternative design strategies in the provision of environmentally friendly educational facilities with low-cost yet adequate learning conditions. Considering the current conditions, the premise is set that required design strategies call for an integrated strategic approach. This is to promote sustainable development models as post-disaster responses. The “Nasma” project is then taken as a case study that exemplifies a sustainable pilot project as a post-disaster response. It is an educational unit developed and implemented in Lebanon by the author in collaboration with a team from Transsolar climate engineers led by Christian Frenzel. It therefore represents a paradigm of integrated architectural and environmental design strategies taking into considering the complex socio-political context of refugee settlements in Lebanon’s Bekaa Valley. The project aims to provide visual, air, thermal and acoustic comfort. It also integrates innovative structural systems and construction methods that allow the school to be rapidly deployed and relocated. Strategies that aim towards social impact include using local materials and engaging the community in the building process. Finally the paper concludes by assessing the actual performance of the structure as a replicable post-disaster response.

Long span bridges and high rise buildings are two types of structures that have always arisen the atten­tion of engineers and architects. The former are appropriate for creating crossings over wide rivers or estuaries in a sort of recreation of the geography of our planet. The latter are many times used to be a symbol of the wealthy of the cities where they are erected.

Construction of both typologies has experienced a dramatic activity since the last decades of the past century in many countries located in different continents such as Europe, Asia or America, and such tendency has even increased in recent years, and several challenging proposals have also been proposed for the years to come.

This article starts with a brief description of the capabilities and advantages of long span bridges and tall buildings. Afterwards, a description of the main realizations of suspension and cable-stayed bridges already existing all around the world is presented mentioning their main characteristics and fea­tures. Additionally, information on bridge projects that could take place in a near future are mentioned. Then, a similar treatment is carried out for the vast collection of signature buildings erected in the last decades. It will be observed that in addition to the new tall structures in already very cosmopolitan cit­ies, many of them have been built in other places and have transformed radically the skyline of cities in China, Singapore, Korea or the Arabic Gulf countries, to name a few.

Environmental problems have been increasing at a disproportionate rate, contributing to global warming, one of humanity’s greatest challenges. As stated in the latest report of the Intergovernmental Panel on Climate Change ‘climate change is widespread, rapid and intensifying’ and there is certainty that this is a result of human activity. In this context, environmental social responsibility is fundamental to prevent, mitigate or repair the environmental damage generated by productive activity. This obliges us to take concrete actions and thus move from a linear economy approach to a circular economy approach that allows for sustainable development, where waste and pollution are eliminated from the design stage and materials are used for as long as possible. Chile must implement actions that allow it to meet the commitments obtained in its Nationally Determined Contribution of 2020, and move towards sustainable development. The Chilean case is interesting to study because it is a highly exposed and fragile country in the face of climate change. The purpose of this publication is to highlight the current problem of climate change and the threat it poses to our planet, to understand that the circular economy approach as a business model allows for a long-term solution to this problem, to understand the consequences of climate change in Chile and to know the current situation in terms of strategic planning at the country level in relation to the circular economy.

The article explores the problem of train rescheduling based on the actual situation. The proposed stochastic model uses specific distributions of operating times which are dependent on the current traffic conditions. The arrival time distribution is considered as a result of adjusting the train trajectory by speed control. The results of modelled arrival distributions correspond well with the experimental data received at the russian railways. The proposed model is used for prevention of sequence-of-trains conflicts and violations of connections. The basis of deviation prediction is two-train model of mesa-level which uses actual features of scattering of the operation times both at sites and at stations. The article also proposed a new measure of arrival delay which considers the share of satisfied passengers.

The paper deals with the optimization of a single-storey timber building structure designed from timber portal frames connected with steel purlins, rails and façade columns. While the portal frames are made of the glued laminated timber with rectangular cross-sections, purlins, rails and façade columns are made of commercially available steel I-profiles. The portal frames are supported by square concrete pad foundations. The building structure is optimized by a mixed-integer non-linear programming (MINLP). The optimization model is developed. The objective function defines the material costs of the structure. The objective function is subjected to structural analysis and design constraints defined according to Eurocode standards. The Modified Outer-Approximation/Equality-Relaxation algorithm (OA/ER) and the linked multi-level strategy are applied. The optimization determines the minimum material costs of the structure, the optimal number of glulam frames and steel members and all standard/discrete cross- sections. A numerical example at the end of the paper shows the efficiency of the proposed optimization approach.

As large consumers of energy, cities offer the opportunity for significant energy savings in relation to the implementation of energy-efficiency measures. In this context, the cities of Barcelona, Cologne and Stockholm, together with a diverse group of stakeholders from public and private sectors, joined to create the GrowSmarter project. GrowSmarter seeks to demonstrate and stimulate the uptake of Smart Solutions in energy, infrastructure and transport, to provide other cities with insights and create a ready market to support the transition to a sustainable Europe. With the objective of promoting and developing low-energy districts, a set of solutions were tested aiming to reduce their environmental impact. These are classified in three blocks: building energy retrofitting, energy consumption visualization platforms and local energy generation with smart management. All these actions have been technically and economically evaluated in GrowSmarter, and the results are presented in this article. The project has analysed different impacts of active and passive retrofitting measures in building energy performances and the feasibility of the proposed business models behind them. Energy visualization platforms have proven to be a promising tool to engage end users, but there is still work to do to define successful business models. The assessment of the deployment of local energy generation units shows that the corresponding regulation differs to a significant extent among countries. A clear and harmonized regulation according to the current state of technology is required in order to fully deploy distributed energy resources at commercial level. Finally, besides guaranteeing the correct implementation and operation of energy-efficiency measures, communication and information campaigns are key to build trust and ensure user acceptance. Working on building users’ awareness and acceptance has proven to be a must in order to succeed in making low-energy districts the preferred path in urban development.

Particle size reduction of dry granular material by mechanical means, also known as milling or comminution, is undoubtedly a very important unit operation in pharmaceutical, agricultural, food, mineral and paper industries. As comminution is a stochastic and a nonlinear process, an attempt was made to understand this complicated process by conducting parametric studies experimentally and computationally using discrete element method (DEM). Greater size reduction was observed at higher rotational speed of the hammer owing to the greater centrifugal force experienced by the particles. Increase in impeller wall tolerance resulted in rolling mode regime of powder bed, which was found to be significant at low impeller speeds. A numerical model based on DEM was used to simulate a hammer mill and study the breakage and kinematics of the particle motion within the hammer mill. In the simulations, increase in hammer tip speed causes higher frequency of impact of particles per unit time and higher specific energy of impact resulting in generation of much finer end product. A limit can be conceived during the breakage event. This is because as size reduction occurs, the breakage rates can fall for very fine particles as crack propagation ceases. This is because as size decreases the probability of finding a flaw also decreases. Simulations also showed a higher milling rate for big hammers as larger hammers decrease the tolerance between the milling chamber and rotating impeller. To study the effect of material properties, the energy of fragmentation was estimated and it was found to increase as the material became more cohesive.

This paper is focused on assessing the effects of floods on selected components of the environment. The components include the impact of floods on the population, water conditions, soil, fauna, flora and their habitats, the structure and use of the landscape, protected areas and their protection zones, for the territorial system of ecological stability, for the urban complex and land use, for cultural and historical monuments, cultural values of an intangible nature and for archaeological and paleontological sites and important geological localities. The basic principle of the methodology is the calculation of the risk index – an estimate of the level of risk that the proposed activity represents for the environment. The risk analysis is based on the principle that stressors are associated with the proposed activity, which poses a certain risk to the components of the environment. This can be quantified by calculating the individual risk for each identified environmental impact of the stressor. In summary, the total risk can be calculated, which represents what risk the proposed activity poses to the environment and human health. The calculated value of total risk represents very low level of risk in the addressed river basin. As a proposal for measures in the event of floods, a Draft Protocol providing health and social care in case of floods is created. The Draft Protocol may be used as a supplement to the Flood Management Plan from the point of view of providing health and social care.

All large railway networks use a mixture of outdated, modern and emerging signalling and train operation principles. There is a need to develop novel modelling and verification mechanisms to support mixed traffic scenarios, including, for example, mixing different types of signalling and driving. In our previous work we introduced the Unified Train Driving Policy (UTDP) formal modelling language for uniformly capturing diverse signalling principles and mixing, in a demonstratively safe manner, at the node and/or network-level novel and legacy signalling principles. This paper describes our work on making UTDP practical and useful for the engineers.

This work reports a summary of different type of analyses and modelling approaches, typically adopted by practitioners and researchers for the prediction of the seismic response of multi-storey CLT buildings. Specifically, two different modelling approaches are deeply investigated and compared; the first one is a component approach, which adopts springs (linear or non-linear) for connections, while the second one is based on a simplified phenomenological model where the behaviour of the system is reproduced by means of diagonal springs (linear or non-linear). The advantages and disadvantages of the two approaches are presented and critically discussed with reference to the types of the performed analysis (linear or non-linear).

In order to verify the capability of the two modelling approaches to predict the seismic response of CLT structures performing linear analyses, a series of multi-storey buildings with increasing number of storeys and increasing values of design PGA are investigated. Obtained results are compared in terms of principal elastic periods, internal forces in the connection elements and drifts. Moreover, some correlations between results from the component and the phenomenological approach are given. Then, a first attempt of defining a numerical model suitable for non-linear analyses of a single CLT shear-wall, according to both the component and the phenomenological approaches is presented. Finally, the obtained results are discussed, highlighting the key issues in non-linear modelling of CLT structures.

A numerical investigation is carried out to evaluate the influence of the gap between the bluff body and the bed on the wake characteristics generated in shallow flows. A sharp-edge bluff body with a fixed gap from the bed is employed in the study, and the results are compared with the no gap case. A sharp-edged bluff body was chosen to minimize the effect of reynolds number and ensure fixed flow separation points. The transient three-dimensional Navier–Stokes equations are numerically solved using a finite volume approach with the detached eddy simulation turbulence model. The flow field in this study involves two different fluids, i.e. water and the air above it. The volume of fluid method is used for tracking the free surface separating the water and air. The fluid structures that are generated in the wake are identified using the λ2-criterion. The results reveal that the gap flow will develop a new structure near the bed, which enhances the upwash flow immediately after the submerged jet is about to turn upwards due to the weak hydraulic jump. This structure plays an important role in recovering the free surface to its original shape at a shorter downstream distance from the bluff body than when there is no gap.

The use of low-cost devices for air quality monitoring is rapidly growing, and the reason behind the growth might (at least partially) be the real-time monitoring at a lower fixed and operating cost, ease of use and portability. nevertheless, the poor data reliability of low-cost sensors (LCS) remains a considerable challenge, especially when deployed in real-world conditions. This study aimed to evaluate and improve the performance of two commercially available indoor air quality monitoring LCS devices: AirVisual Pro and uRAD Monitor A3 (uRAD), which were used to monitor CO2 via non-dispersive infrared technology. The analysis took place from June to July 2019 in several classrooms of an urban school in Porto city. Machine learning techniques such as multivariate linear, support vector, gradient boosting and XGBoost regression models were used to perform an on-field calibration for improving the data accuracy of the devices. The results showed that although both the devices showed a strong linear correlation (r > 0.9) with the reference device, they might indicate deviated CO2 concentrations if used in their advertised plug and play format. Specifically, uRAD showed a steady offset compared to the reference values, while AirVisual Pro showed lower deviations than uRAD. The on-field calibration models improved the reliability and showed low root mean square error values (around 30 mg/m3) and a high coefficient of determination (0.99).

To preserve the harmony within a vernacular habitat, a delicate balance between living space, nature, and community must be maintained. This paper analyzes local communities from Maramureș, Romania, and their sustainable ways of living, and it also discusses the use of locally sourced materials in building settlements: a cautious combination of progressively integrating contemporary living solutions with preserving the powerful local heritage. Such initiatives become more challenging given that new, modern developments and rapid industrial changes tempt people away from ancient custom. In order to sustain the traditional habitat, as fundamental for the heritage preservation initiative, it is necessary to guide villagers in finding value and beauty locally and discourage them from migrating towards bigger cities or other countries. Based on two case studies of local craftsmen, Maria Zapca, a weaver from Săpânța, and Daniel Leș, a potter from Baia Sprie, the journey starts in Săpânța, home of the UNESCO heritage site The Merry Cemetery where the physical fabric of the place lends itself to sustaining local crafts and craftsmen. However, this is not an isolated case: Maramureș is famous throughout the world for its material culture such as wooden churches with tall spires – seven of them listed as UNESCO World Heritage Sites – alongside a multitude of home decorating fabrics and traditional attire still made and used by locals. Regional resources such as clay, wood, stone, wool, or hemp stand as fundamentals in shaping the vernacular habitat. Furthermore, the region is well-known for preserving customs and practices, which emphasize local group members’ lineage to the wider community. People are proud of their heritage and are connected to the cultural values that help shape their identity.

Climate change effect on water quality performance of lakes, rivers and streams is a significant concern for watershed planning and management. Climate change characteristics may potentially increase the likelihood that waterbodies will fail to meet established water quality standards, often obligating watershed managers to undertake expensive monitoring and load allocation studies for possible remedies against such impairment. One such load allocation study involves the implementation of water quality trading (WQt), which often is proposed as a mechanism for improving surface water quality goals under a socially and economically feasible manner. However, while future growth and land use change is incorporated through a margin of safety, WQt markets do not typically incorporate the characteristics of climate change that have been suggested to exhibit strong linkages against achieving the desired levels of water quality benefit. Consequently, this modelling study evaluates the characteristics of climate change upon the levels of water quality benefit along a river system subject to distinct load removal exercises: a) removal upon point sources only and b) removal based on a point–nonpoint source trad- ing mechanism under a theoretical WQt program. this study applies such assessments upon the load allocation exercises through carbonaceous biochemical oxygen demand reduction for addressing a recognized dissolved oxygen problem along the Jordan river in Utah, conducting such analyses through selected climate change projections described by the representative concentration pathways. For achieving such tasks, separate simulations are conducted through the Water Quality Assessment simulation program, evaluating the performance of such trading mechanisms under observed meteorological data against modelled climate data through selected representative concentration pathway projections under a historical period from Water year 2007 to 2009. This exercise assesses the performance of such load allocation studies subject to climatic characteristics toward suggesting linkages among climate change, water quality benefit and the effectiveness of a theoretical WQt mechanism.

In dependence upon a given geometric configuration, an actual or forecasted number of vehicles arriving at an intersection can turn left or right, otherwise proceed straight through it. This article can be placed in between a research working paper, and a kind of informational brief report. Indeed, it deals with forecasting techniques for estimation of intersection turning movements. Such issue is crucial, both in network planning and in traffic engineering, while its applications span from traffic safety and environmental impacts, to signal timing, roundabout design and setting of traffic control strategies. The number of vehicles making each movement on an existing intersection can be manually collected, especially when operational analyses are undertaken. Nevertheless, when the intersection is at the planning or design stage, an estimation process is required. In its first part, this paper provides a brief literature review of some of theoretical and practical methods focused to forecast the intersection turning movements. Such a review is limited on methods used to distribute the incoming and exiting traffic volumes within the different intersection branches, then generating an estimation of the so-called intersection O/D matrix of turning flows. The second part of the paper is experimental. Two different, but similar, heuristic procedures have described. Then, they have successively applied to some selected intersection real traffic data sets, and the respective computational performances were compared. Namely, the first one is known as proportion methods, while the second one is called as the difference, or deviation, method. Each method of these two starts from an initial matrix, and through iterative steps it reaches the best estimate of the matrix of turning flows, with respect to a given distribution model. Test intersections with their related set of real traffic data have been used as input, and each of the two procedures, as described in advance, was applied to the same numeric instances. The obtained values were compared in respect to few selected performance indicators. Finally, the computational results were displayed and discussed. On this basis, some insights are drawn and useful remarks for application and future research have been addressed.

Climate change has led to triple digit temperatures globally, notably along the western coast of the United states. These changes have produced intense weather-related events such as fires and landslides. Green roofs are one strategy to mitigate these high temperatures. For this report, several studies were compiled, using data found from physical green roof models as well as on-site data from the Javits Center Green Roof. At the Javits Green Roof, an infrared camera was used to collect thermal images at various parts of the roof, to determine its effectiveness for thermal buffering. Off site, a rain simulator was used on model green roof and a control roof, to determine change in retention and peak runoff rate. The green roof was able to retain 2%–22% of rainfall and reduce peak runoff by 19%–28%. From the graph comparing roof temperatures, there were higher temperatures on the black top roof in comparison to the green roof, and the slopes of the lines indicated the mitigating effect of the green roof on heat waves. These models were also analysed with an infrared camera, which showed that green roofs can be, as much as 25°f cooler than their standard roof counterparts, providing valuable evidence for the usefulness of green roofs to combat heat waves. Runoff quality was experimentally measured using a green roof model, where nitrogen concentration is measured before and after to determine change in runoff quality. This concept is based on studies which claim that the addition of wood mulch to soil can reduce nitrogen content. This experiment revealed a 23% reduction in runoff nitrates for the wood-mulch treated soil, in comparison to a 6.5% reduction for the control roof. Furthermore, a mathematical model was used to determine the ceiling temperature of the Javits Center within 3%.

The Amazon is facing challenges for solid waste management, due to its social, environmental and economic vulnerabilities. The main goal of this research was to investigate barriers of integrated municipal solid waste (MSW) management for the Amazon, applying the Delphi method. A consultation with waste management experts allowed raising the main alternatives recommended for that geographical region. In addition, in loco surveys evaluated the MSW management of three cities from Southwest Brazilian Amazon (SWBRAM): Humaitá and Manicoré, in the state of Amazonas (AM), and Ariquemes, In the state of Rondônia (RO), Brazil. A total of 35 experts responded to the consultation, and there was unanimity that the prevention of solid waste generation should be encouraged in the Amazon. There was a consensus on the treatment of MSW in the Amazon: composting of organic waste (88%) and recycling of dry waste (86%), in addition to the disposal of MSW in landfills (83%). The municipalities of Humaitá and Manicoré collect and dispose MSW in dumps. However, in Manicoré, there is a Recyclable Material Collectors Cooperative that diverts about 3.0 t month-1 of recyclable waste from the dump. Ariquemes disposes its MSW in the only sanitary landfill of SWBRAM, which receives about 135 t day-1 of the MSW generated in the 14 municipalities that form an Inter-municipal Consortium. The main challenges raised for the MSW management in the Amazon were as follows: investments in preventing MSW generation; supporting the creation of Cooperatives and the social inclusion of waste collectors; improving and integrating the river and road modals; creating conditions for the commerce of materials in Manaus recycling market; and supporting the creation of Inter-municipal Consortium for landfill construction and operation.

This paper deals with the economic optimization of high-performance post-tensioned concrete box-girder pedestrian bridges. To this end, a program analyzes and evaluates the structural restrictions following Spanish codes for structural concrete and bridge design loads. This problem includes 33 discrete design variables that define the geometry, the concrete, the reinforcing steel bars and the post-tensioned steel. Various acceptance criteria are proposed to modify a variant of the simulated annealing algorithm with a neighborhood move based on the mutation operator from the genetic algo- rithms (SAMO). An objective methodology based on the extreme value theory is used to determine the number of experimental tests required to provide a solution with user-defined accuracy as compared to a global optimum solution. Results indicate that the local optima found by SAMO2 fits a three- parameter Weibull distribution and improves the cost results for this structural problem. The minimum value obtained by SAMO2 differed just 0.34% compared to the theoretical minimum value so that, from the structural engineering perspective, the divergence was small enough to be accepted. High-strength concrete performance was further studied in a concrete strength parametric study to acquire more evidence-based knowledge on its implications for economic efficiency. Finally, the study showed that high-strength concrete decreases the cost by 4.5% and the amount of concrete by 26%.

This research presents analytical and mathematical modelling of coating failures within industrial components, structures, mobile assets and systems due to corrosive degradation and mechanical fracture. These failures lead to several surface problems; therefore, contact mechanics and electrochemistry approaches incorporating induced residual stresses have been adopted to develop a comprehensive solution for the prediction and prognostic of such failures. Experimental study of film cracking and its propagation into substrates, interfacial transient behaviours and film-substrate system has been conducted. A parallel study of corrosive degradation to include cathodic delamination, cathodic blistering and tribo-corrosion of films has been conducted. Experimental and analytical studies of induced residual stresses within the coating and their effects on failure mechanisms and propagation have been completed. A detailed investigation of elastic mismatch at the interfacial contact and interfacial crack tip field has been performed and a complex stress intensity factor is presented. Mathematical derivation of oscillatory singularity, mode mix and interfacial fracture criterion to include adhesion are presented. This paper presents novel mathematical modelling incorporating interfacial crack propagating, diffusion of corrosive species and cathodic blistering for prediction and prognoses of coating failures.

The linear coupled stretching-bending problem for general laminates is here formulated with the mid-plane stress function and the lateral deflection as independent field variables. A mathematical similarity between the two problems is achieved by introducing a re-arranged mid-plane strain tensor as one of the dependent variables. As a step towards a genuine boundary element solution for this problem, its fundamental solutions are derived using a Fourier transform approach. First, the transforms of the solutions are obtained in terms of the transform space variables and their inverses are deduced using complex integral calculus. Through the use of these fundamental solutions, boundary integral equations of the linear coupled stretching-bending problem are formulated without the presence of any irreduc- ible domain integrals. Issues regarding the numerical implementation of this formulation are raised and discussed.

Private vehicles have dominated personal transportation for the past 50 years. They provide positive externalities such as accessibility and independence. However, their widespread use in urban areas has resulted in negative externalities such as traffic congestion, air pollution, human health problems and damage to the ecosystem. Therefore, understanding the underlying factors affecting car ownership has become an important research theme. This study focuses on assessing the main socio-economic factors that affect household car ownership in Belgium. To this end, we developed a household car ownership model based on the 2016 Belgian household travel survey. Overall, our results confirm the literature review’s findings, highlighting the importance of socio-demographic and economic characteristics of households in explaining household car ownership. The results from the multinomial logit model show that: (i) income is positively associated with car ownership, (ii) living in Flanders and wallonia increases the probability of having two or more cars compared to living in Brussels, (iii) having a driving license increases car ownership, (iv) a larger number of adults and children in a household is related to a higher likelihood of owning two or more cars per household, (v) higher level of education increases the probability of having more than one car per household and (vi) older people (65+) are less likely to have multiple cars. The results of this study can be used as a tool for researchers, policymakers and urban planners to define more effective sustainable mobility policies.

It is important for urban tourism development to focus on the accessibility of tourist points of interest (POIs). The spatial distribution of POIs should be closely linked to sustainable traffic development. In recent years, smartphones and global positioning systems have provided strong technical support for tourist POIs through social media. Many studies have been conducted to investigate the correlation between POIs and transportation from different perspectives. There is however a lack of quantitative research on the correlation between traffic accessibility and the distribution of urban tourist POIs using space syntax theory. This study proposes a method for optimizing the layout of tourist POIs based on traffic accessibility. We crawled 2,322 tourist POIs in Dalian as research objects, adopted kernel density estimation and constructed spatial syntax models. We analysed these models from the perspective of the spatial distribution characteristics of the POIs and traffic accessibility. The results showed no di- rect correlation between the spatial distribution of POIs and road networks. The conclusion is that the distribution of the most popular POIs does not coincide with the roads with the highest accessibility in Dalian. Therefore, we propose feasible optimization strategies for spatial planning of tourist POIs and sustainable traffic development.

Energy utility companies face trade-offs in navigating through today’s environmental challenges. On the one hand, they face intense political, social and environmental pressures to move toward adopt- ing energy systems that incorporate the use of renewable energy resources. By making this transition, they would contribute to carbon reduction and mitigate climate change. On the other hand, they need to coordinate their resources and become efficient when investing in new plants or upgrading existing production systems. This paper seeks to address the gains that utility companies can make when replacing older fossil-fuel-based plants with efficient combined heat and power (CHP) plants. We discuss the system effects from the changes in production of other units when new plants are constructed. Using one of the largest energy utility companies in Sweden, Fortum, as empirical point of departure, we analyzed the company’s transition from using coal and hydrocarbons to an increased use of renewables and waste incineration CHP. Our analysis was based on comprehensive production data on CO2, SOx and NOx emissions. Our findings suggest that primary energy consumption drops when older, less efficient fossil plants are substituted for new efficient CHP plants; this drop includes the effect on remaining production. The benefits in terms of primary energy savings might even be greater than what is achieved in meeting the goal of climate change abatement through reduced CO2 emissions; NOx and SOx emissions are decreased with new biomass CHPs. Waste incineration CHP increases NOx and SOx emissions, when there is less fossil fuel to replace after the use of biomass is extended. In both cases, economic efficiency increase as costs are reduced.

Optimized energy generation and smart distribution in a sustainable manner requires accurate prediction of its consumption. However, the prediction of energy demands of households remains a tedious task due to variations in patterns of energy usage. Mathematical models and artificial intelligence (AI), such as smart energy-efficient designs, strategic planning for smart grids, and Internet of Things (IoT)-enabled smart homes, have recently been considered as solutions to these issues. A major issue encountered in energy consumption prediction systems is their restricted prediction horizons, as well as their dependence on one-step predictions. This study, therefore, suggests an innovative model for the prediction of energy demand that uses a long short-term memory (LSTM) and fractional differential equations (FDLE)-based model. The proposed LSTM-FDLE model was trained to predict the collective active power generated by household devices. LSTM’s memory and sequential learning capabilities were also explored in the proposed model for comprehending the complex temporal dependencies and trends in energy consumption data. The performance of the proposed model was evaluated on real-world household energy usage data and found to achieve good prediction accuracy; the performance of the model was also better than that of some conventional one-step prediction models. Therefore, better energy generation planning, and optimal distribution systems can be achieved by the longer forecasting period provided by the proposed “LSTM” model.

Indoor air quality in subterranean train stations is a concern in many places around the globe. However, because of the specificity of each case, numerous parameters of the problem remain unknown, such as the braking disc particle emission rate, the ventilation rate of the station or the complete particle size distribution of the emitted particles. In this study the problem of modelling PM10 concentration evolution is hence addressed with a particle-mass conservation model which parameters are fitted using a genetic algorithm. The parameters of the model allow to reproduce the dynamics and amplitude of the measured data and comply with realistic bounds in terms of emissions, deposition and ventilation rate.

Society has done little to modernize energy delivery or take advantage of proven, commonly available technology. in the past, change was driven by regulated entities with an exclusive franchise. today, however, disruptors come from outside of the power sector – a phenomenon that is changing the grid. the grid of the future will provide an open platform, similar to a state-owned interstate that allows access to all. generation, storage, and load elements will be self-registering building blocks, similar to the concept of all ‘lego’ sets being compatible. elements will be connected by providers or even consumers, they will self-register, and interact with each other optimizing grid performance with respect to economics, efficiency, adequacy, and reliability. the ubiquitous grid will encompass not only electric, gas, and water, but other services that either we’ve already come to rely upon or haven’t even considered yet. is this farewell to the grid as we know it? the exclusive franchise model that has been around for more than a century might not be as long lived as expected.

The establishment of the Sustainable Development Goals in 2015 claims for a deep paradigm shift in the way infrastructure structures are conceived. The evaluation of the impacts derived from the con- struction, the service and the end-of-life stages of an infrastructure is consequently in the spotlight of the research community. Being the construction sector as one of the main stressors of the environment, great attention has been recently paid to the structural design from the economic and the environmental point of view. However, sustainability requires to consider the social dimension as well. The evaluation of the social impacts of products is still at a very early stage of development, so the inclusion of social aspects in the design of structures is often overlooked. In this study, a comparison of life cycle assess- ment results is conducted on seven different design alternatives for a bridge in a coastal environment. Two approaches are followed: the first approach considers the economic and the environmental aspects of each design and the second approach includes the several social impacts specifically developed for the assessment of infrastructures. These social impacts account for four stakeholders, namely workers, consumers, local community and society. Results show that the inclusion of social aspects shall lead to different preferred options when compared with conventional, two-dimensional approaches. Here, the design with silica fume added concrete performs 11% better from a sustainability point of view when compared with the best solution resulting from a conventional assessment.

Tourism is a fast-growing key industry, which provides an economic rationale for governments to stimulate it. The more it grows, the higher the negative environmental effects and the more the use of space, resources, pollution and travel. Sustainable tourism aims to strike a balance between the environmental, economic and social effects of tourism. The aim of this article is to find the optimal itinerary for an individual traveller to a congress hotel in Valencia. The main research question is as follows: Which itinerary has the best overall score in terms of CO₂ per passenger kilometre, travel time and direct cost? Three scenarios were compared: Airplane plus, train plus and car only. The choice of these three suits the travel purpose and length. Literature was used to find the necessary trip and vehicle data. This was fed into a microsimulation model. The main outcome of the simulation experiment is that the environment would benefit if the traveller would favour the train plus scenario. This, however, has a time penalty compared to the airplane plus scenario. A trip by car is the least preferable, because of CO₂ emissions, travel safety and time. Direct costs of all three scenarios are comparable. Rail has the low- est emissions per passenger in the scenarios, hence it is important that network improvement programs continue and ticket prices stay in line with the price of travelling by car or airplane. An individual trav- eller was chosen for different reasons. One reason is that after understanding individual touristic travel decisions and their impact, it is a small step to estimate what is feasible if many more individuals would become ecofriendly touristic travellers. A second reason is that it allows an advice for governments and businesses to target individual tourists. Finally, there is the communicative impact of simplification on individual tourists.

Efficiency is becoming more and more a main concern in the design of power transmissions and the demand for high efficiency gearboxes is continuously increasing. Also the more and more restrictive euro standards for the reduction of pollutant emissions from light vehicles impose to improve the efficiency of the engines but also of the gear transmissions. For this reason the resources dedicated to this goal are continuously increasing. The first step to improve efficiency is to have appropriate models to compare different design solutions. Even if the efficiency of transmissions is quit high if compared with the efficiency of the engines and appropriate models to predict the power losses due to gear meshing, to bearings and to seals already exist, in order to have a further improvement, some aspects like the power losses related to the oil churning, oil squeezing and windage are still to be investigated. In previous papers the authors have investigated by means of computational fluid dynamic (CFD) analysis and experimental measurements the churning losses of planetary speed reducers (in which there is a relative motion between the “planets + planet carrier” and the lubricant). Also the windage power losses have been studied by the authors in previous papers. This report is focused on the oil squeezing power losses. This kind of losses is associated with the compression expansion process by the meshing teeth. The contraction of the volume at the gear mesh implies an overpressure that induces a fluid flow primarily in the axial direction and this, for viscous fluids, means additional power losses and a decrease of the efficiency.In this work this phenomena has been studied by means of some CFD simulations. The influence of some operating conditions like the lubricant properties, the rotational speed and the temperature has been studied.

Water is considered the most important natural resource in the four Pacific Northwestern states (Alaska, Idaho, Oregon and Washington). Public attitudes about water resource issues and needs were deter- mined using a mail-based survey instrument every 5 years (2002, 2007, 2012 and 2017). The survey questions were identical over the 15-year period. The statistically designed survey study was also designed to measure change over the 15-year time period. Four specific survey questions were evaluated in this article. In 2017, over 83% of the public considered their home drinking water safe; however, this value was lower and compared unfavourably to the 93.1% who considered their drinking water safe in 2002. In 2017, 43.8, 40.7, 28.3, 25.3, 19.4 and 14.8% of residents considered phosphates, nitrates, pesticides, pharmaceuticals, petroleum products and pathogens as problems in local waters, respectively. Compared to the 2002 survey, the perceived problem of phosphates, nitrates and pharmaceuticals has become worse; however, public views of problems caused in waters by pesticides and petroleum prod- ucts have lessened. Based on public perception, the problem of pathogens in waters has not changed over the 15-year span. Surface water and groundwater quality were considered to be excellent or good by 51.6 and 46.2% of survey respondents in 2017, respectively. In general, public views of water quality have improved since 2002.

The stability of a vehicle (especially if operating off-road, such as a farm tractor, possibly with an im- plement attached) can be statically investigated by means of a test installation such as the one described here. It consists of a platform (dimensions: 6.42 × 4.46 m) having two degrees of freedom (inclination, rotation) and on which the vehicle is positioned motionless. By acting on these degrees of freedom, it is possible to precisely and simultaneously control all the characteristic angles of a vehicle (roll, pitch, yaw), thus discovering, in complete safety, its operational limits (i.e. its incipient rollover conditions). Furthermore, the ability to misalign up to two of the four quadrants composing the platform allows the testing of further critical situations for the vehicle, in which the front-axle pivot joint and the tyres elasticity are involved, potentially up to a scenario in which the vehicle rests on only three of its four supports and its support polygon degenerates into a triangle. The basic test scenarios that can be investigated with this installation allow the study of many aspects of a vehicle, pertaining both to the general chassis performance of the vehicle (therefore related to its balance) and to the load state of some spe- cific components (internal or interfacing the vehicle with the outside, e.g. the wheels). The obtained data, referred to reference test scenarios, allow the experimenters to: (1) interpret sensors readings in real operating situations, thus including also the contribution of the tyres vertical flattening and lateral deflection, (2) complete the safety documentation at the users’ disposal with some specific graphs, the vehicle ‘equilibrium maps’ (or ‘stability charts’), possibly referred also to the vehicle with some accessories/implements connected to it. By demonstrating the undeniable usefulness of such an installation, the authors hope to propose new testing paradigms with the ultimate aim of increasing the overall safety of vehicles and, particularly, of agricultural and work machinery.