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Loop unrolling is a well-known code-transforming method that can enhance program efficiency during runtime. The fundamental advantage of unrolling a loop is that it frequently reduces the execution time of the unrolled loop when compared to the original loop. Choosing a large unroll factor might initially save execution time by reducing loop overhead and improving parallelism, but excessive unrolling can result in increased cache misses, register pressure, and memory inefficiencies, eventually slowing down the program. Therefore, identifying the optimal unroll factor is of essential importance. This paper introduces three ensemble-learning techniques—XGBoost, Random Forest (RF), and Bagging—for predicting the efficient unroll factor for specific programs. A dataset comprises various programs derived from many benchmarks, which are Polybench, Shootout, and other programs. More than 220 examples, drawn from 20 benchmark programs with different loop iterations, used to train three ensemble-learning methods. The unroll factor with the biggest reduction in program execution time is chosen to be added to the dataset, and ultimately it will be a candidate for the unseen programs. Our empirical results reveal that the XGBoost and RF methods outperform the Bagging algorithm, with a final accuracy of 99.56% in detecting the optimal unroll factor.

Open Access
Research article
Environmental Problem-Solving Learning Model with Geographic Information System-Based Learning Media
edi kurniawan ,
mohammad syifauddin ,
muh. sholeh ,
sriyanto ,
siti nurindah sari
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Available online: 09-29-2024

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In the era of environmental crises and human challenges amidst rapid technological advancements, geography is an increasingly urgent discipline in comprehending the spatio-temporal dimensions of environmental sustainability. Therefore, effective, innovative, and collaborative implementation of geography learning in schools is essential. This goal can be achieved by emphasizing students’ critical thinking, problem-solving, and spatial thinking skills. The researcher designed an environmental problem-solving learning model to address this need. The environmental problem-solving learning model embraces problem-based learning focused on contextual environmental issues. This research aims to analyze the effectiveness of implementing the environmental problem-solving learning model with GIS-based learning media. The study employs an experimental design that utilizes a one-group pretest-posttest approach. The study group in this research was purposively selected, including 33 students from an urban area school, SMA Negeri 3 Semarang, and 35 students from a rural area school, SMA Negeri 1 Beringin. Data collection involved test methods, observations, and literature review. Qualitative data analysis was performed using an interactive method, while quantitative data analysis employed descriptive statistical analysis and a one-paired sample t-test. This research indicates that the environmental problem-solving learning model with GIS-based learning media effectively improves student learning outcomes. This model promotes active, student-centered learning, encourages collaboration and cooperation among students, and positions students as the primary subjects in the learning process. Furthermore, it fosters the development of critical thinking and problem-solving skills in students. The findings of this research underscore the potential of the environmental problem-solving learning model to be implemented in geography education. Various stakeholders play a crucial role as change agents in promoting innovative transformations in geography learning, including encouraging the realization of GIS-based environmental problem-solving models in various educational contexts.

Open Access
Research article
Development and Application of an Electronic Nose System for Classifying Coffee Varieties Based on Aromatic Profiles
danang erwanto ,
royb fatkhur rizal ,
dian efytra yuliana ,
misbahul munir ,
yuki trisnoaji ,
catur harsito ,
abram anggit mahadi ,
singgih dwi prasetyo
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Available online: 09-29-2024

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Indonesia, a significant exporter of coffee, faces persistent challenges in accurately identifying and classifying coffee varieties based on aromatic characteristics, primarily due to the subjective variability of human sensory evaluation. To address these limitations, an electronic nose (e-nose) system was developed for the classification of coffee varieties through the analysis of aromatic profiles. The system integrates a DHT-22 sensor and four gas sensors (MQ-5, MQ-4, MQ-3, and MQ-135) to measure humidity, temperature, and gas concentrations from coffee vapor. Data acquisition was facilitated by the Arduino Uno platform, while classification was conducted using the Naive Bayes Classifier (NBC) algorithm. The e-nose achieved a classification accuracy of 82.2%, as validated through a confusion matrix and performance metrics, including precision, recall, and F1-score. Among the gas sensors employed, the MQ-4 sensor, which detects methane, demonstrated the highest response sensitivity, whereas the MQ-3 sensor, designed to detect alcohol, exhibited the lowest. This system significantly mitigates the inherent subjectivity associated with traditional aroma assessment methods and offers considerable potential for enhancing quality control protocols in coffee production processes. Future work will focus on integrating advanced machine-learning algorithms, optimizing sensor array performance, and expanding the dataset to include a broader diversity of coffee samples. These advancements are expected to further refine the system's classification capabilities and contribute to more robust quality assurance in the coffee industry.

Open Access
Research article
Benthic Macroinvertebrates as Bioindicators of Water Quality in the Vilcanota River, Cusco-Peru
vilma quispe-illa ,
clarence perez-aguilar ,
jael calla-calla ,
ronald jacobi lorenzo ,
armando calcina colqui ,
geovany vilchez casas ,
andrés camargo caysahuana ,
julio mariños alfaro ,
alex huamán de la cruz
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Available online: 09-29-2024

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Macroinvertebrate metrics are excellent tools for assessing water quality due to the sensitivity of biotic and abiotic parameters of their environment. The work aimed to assess the water quality of the Vilcanota River using aquatic macroinvertebrates and biological indices: Andean Biotic Index (ABI), Biological Monitoring Working Party (BMWP) score, and Ephemeroptera, Plecoptera, and Trichoptera (EPT) index. Macroinvertebrates were sampled at four sampling points (P1, P2, P3, and P4) during dry and wet seasons using Surber traps along a 600 m linear transect. In total, 1631 specimens belonging to 04 classes, 11 orders, and 24 families were found. The class Insecta presented the highest values with 1078 specimens (66.1%), six orders (54.5%), and 19 families (79.2%). The evaluation of the water quality of the Vilcanota River showed that the points during the wet season have questionable water quality for the BMWP and ABI indices. In the dry season, most sampling points (except P1, classified as questionable) showed critical water quality in both the BMWP and ABI index. Similarly, the ETP index revealed regular water quality in the wet season, while in the dry season was bad water quality for most sampling (except P2) points.

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This study proposes an advanced framework for performance evaluation by extending the Malmquist Productivity Index (MPI) to accommodate interval data, addressing the inherent uncertainty and imprecision frequently encountered in institutional assessments. In many contexts, input-output data are often reported as intervals rather than precise values, which poses significant challenges for evaluating productivity changes. The extended MPI model allows for a more comprehensive analysis of performance by incorporating such interval data, thus providing a robust mechanism for assessing both progress and regression in the productivity of Decision-Making Units (DMUs). A case study on university departments is employed to demonstrate the practical application of this interval-based model. The results highlight notable variations in efficiency and technological advancement, offering valuable insights for institutional decision-makers. The proposed methodology enhances the accuracy of performance evaluation in dynamic and uncertain environments, making it a powerful tool for strategic planning and policy formulation. Furthermore, it is suggested that this interval-based approach offers a significant improvement over traditional models by accounting for the uncertainty present in real-world data. The study contributes to the broader field of strategic performance analytics by advancing the methodological understanding of productivity analysis, offering a more nuanced and reliable framework for institutional assessment.
Open Access
Research article
Farmers’ Perceptions of Saline-Sodic Soil Impacts on Rice Production in Navotas, Balayan, Batangas, Philippines
june spencer a. cera ,
josefina t. dizon ,
jocelyn d. labios ,
marcial s. buladaco ii
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Available online: 09-29-2024

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Soil salinization is a critical global issue that undermines agricultural productivity, threatens food security, and compromises the sustainability of farming systems. In the coastal region of Navotas, Balayan, Batangas, Philippines, the increasing salinization of irrigated rice farmlands due to saline-sodic soils has become a pressing concern. The understanding of farmers' perceptions regarding the risks associated with soil salinity, as well as their insights into the causes, consequences, and coping mechanisms, remains inadequately explored. This gap in knowledge may hinder the development of effective countermeasures and appropriate policy interventions. In this study, farmers' perceptions of saline-sodic soils were assessed through Key Informant Interviews (KIIs) and Focus Group Discussions (FGDs), which were analysed using thematic analysis and Causal Loop Diagrams (CLDs). Saltwater intrusion was consistently identified as the primary cause of soil salinization, with subsequent reductions in rice yields ranging from 60% to 100%, depending on the growth stage of the crop. The most vulnerable periods were identified as June to August, particularly during the vegetative and flowering stages of rice. Farmers reported coping strategies such as irrigation with freshwater and the cultivation of salt-tolerant rice varieties; however, challenges related to delayed access to freshwater and seeds were frequently mentioned. The expansion of saline-sodic areas was identified as the most significant threat to rice production, with the condition of saline-sodic soils in lowland rice paddies increasingly viewed as a worsening problem. These findings underscore the severe impact of saline-sodic soils on both agricultural productivity and farmers' livelihoods, providing valuable insights that can inform the development of tailored management strategies and mitigation measures.

Open Access
Research article
Restoring Force Model for Seismic Performance of Corroded Steel Frame Columns
pengfei wang ,
xiaofei wang ,
wei chen ,
jing shi
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Available online: 09-29-2024

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Corrosion-induced damage significantly impairs the seismic performance of steel frame columns, leading to an increased vulnerability during earthquake events. To address this issue, a restoring force model was developed to accurately describe the seismic behaviour of corroded steel columns. Low-cycle repeated loading tests were conducted on corroded steel frame columns to evaluate the effects of corrosion and earthquake-induced damage on their seismic performance. The results revealed distinct degradation patterns, which were systematically analyzed. A cyclic degradation index was proposed to quantify the impact of corrosion on critical parameters, including yield strength, hardening stiffness, unloading stiffness, and reloading stiffness. This index was incorporated into a damage model, which facilitated the formulation of a comprehensive restoring force model for corroded steel frame columns. The developed model was validated through case studies, demonstrating its effectiveness in predicting the seismic response of corroded columns. The findings underscore the importance of considering corrosion damage in the assessment and design of steel frame columns subjected to seismic loading, providing a more accurate and reliable approach for seismic performance evaluation.

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With the growing prominence of environmental issues, sustainable development has become a global consensus. Environmental, social, and governance (ESG) factors have emerged as key focal points for companies and their stakeholders. Using a sample of Chinese A-share listed companies from 2011 to 2022, a comprehensive indicator of attention was constructed from a stakeholder perspective to examine the interactions and mechanisms among ESG quality, attention, and enterprise value. Findings indicate that enhanced ESG performance significantly contributes to increased enterprise value, with attention serving as a critical mediating factor in the relationship between ESG performance and enterprise value. Furthermore, notable differences were observed in this process based on firm ownership, with ESG performance exerting a more substantial impact on enterprise value within state-owned enterprises. These insights offer valuable perspectives for companies on how to leverage improved ESG performance to enhance enterprise value.

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In this study, we investigate the heat and mass transfer characteristics of an unsteady mixed convection magnetohydrodynamic (MHD) flow of Casson fluid through a porous medium in the presence of thermal diffusion and heat source effects. The flow is considered between isothermal inclined plates, incorporating the influences of Joule heating and viscous dissipation. Using dimensionless variables, the governing partial differential equations are transformed into their dimensionless form. The resulting dimensionless equations are solved empirically through the perturbation methodology. The effects of various critical parameters on the velocity, temperature, and concentration distributions within the boundary layer are analyzed with the aid of graphical representations. Additionally, numerical values of skin friction, Nusselt number, and Sherwood number near the plate are examined for different parameter values and presented in tabular form. The findings provide a deeper understanding of heat and mass transfer mechanisms in MHD flows through porous media, which are relevant to various industrial and engineering applications.

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Electromyographic (EMG) analysis was conducted to evaluate the functional characteristics of masticatory muscles in patients with myogenous temporomandibular disorders (TMD), aiming to enhance the clinical understanding of muscle activity in these conditions. Based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD), 28 patients with myogenous TMD, characterized by persistent pain exceeding six months, were examined alongside a control group of 35 asymptomatic subjects. EMG assessments were performed on the masseter, temporalis, and suprahyoid muscles during resting states and maximum intercuspation clench. Quantitative parameters, including myoelectric indices in the amplitude domain and mean power frequency (MPF) in the frequency domain, were evaluated. Significant differences in muscle activity patterns between the TMD and control groups were observed. During maximum clenching, temporalis muscles (TA) in TMD patients exhibited a markedly higher asymmetry index and activity index, alongside a lower MPF, compared to the control group. Conversely, the MPF of the suprahyoid muscles was elevated, while masseter muscles (MM) displayed a reduction in MPF. In the resting state, the MPF of the TA was found to be higher than that of both the control group and the MM. These findings indicate that patients with myogenous TMD exhibit increased muscle activity asymmetry, reduced coordination, and altered frequency-domain characteristics of the masticatory muscles. The results suggest that the TA may play a more significant role in the compensatory mechanisms associated with myogenous TMD, potentially contributing to the observed dysfunction and pain. This study underscores the utility of EMG as a diagnostic tool for elucidating the pathophysiological changes in masticatory muscle function in TMD and highlights the potential for targeted therapeutic interventions based on these findings.

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As ecological civilization becomes a key national development strategy, green finance, which aims for sustainable development, plays a significant role in fostering regional economic growth. At the same time, local governments actively respond to central policies and, in the process of exploring financial reform and innovation, need to quantitatively assess the effectiveness of these policies. This paper takes the establishment of Green Finance Reform and Innovation Pilot Zones as a quasi-natural experiment to examine the impact of this policy on regional economic growth and its underlying mechanisms. The study finds that the establishment of Green Finance Reform and Innovation Pilot Zones effectively promotes regional economic growth, and the conclusion remains robust after conducting various sensitivity analyses. Further heterogeneity analysis explores the differing impacts of the policy in various regions, while considering green innovation as a positive mechanism mediating the relationship between the policy and economic growth. This study provides insights into the shift from “quantity” to “quality” in regional economic development.

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The WBM’s viscosity, gel strength and ability to filter and control the filtration rate are central to the stabilization of the well bore as well as the transportation of the cuttings to the surface. WBM is comprehensively inexpensive and eco-friendly; it does not hinder the biodegradation process as compared to other chemicals that may be used in the drilling involving rig activities. It cans thermally change, regulate formation pressure, and support cuttings. WBM is also can be used in all types of formations and is not complicated in terms of its handling as well as disposing as compared to other drilling fluids. However, WBM has some limitations as it is influenced by shale hydration, formation water salinity and thermally less stable at high temperature formations. Hindered by formation solids, fluid loss to the formation and formation damage are other issues that must be dealt with efficiently during the drilling process using WBM. WBM is used in most practices of drilling especially in offshore drilling areas, environment sensitive areas, and areas that have certain restrictions on the types of fluids to be used in drilling. Effectiveness and flexibility in relation to various platforms and various rigs make it a prime candidate for the most orthodox as well as the most innovative operations. Some of the regular water based muds that are often in use are Spud mud, Low solid polymer mud KCl, PHPA polymer mud KCl, Glycol polymer mud, Salt Saturated mud and Drill – in mud.

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The global iron and steel sector is currently navigating a period marked by significant volatility, driven by rising overcapacity and stagnating demand. In this challenging environment, businesses are increasingly compelled to compete not only within their local markets but also on the international stage, as the global economy becomes ever more interconnected. This necessitates a thorough evaluation of the financial performance of major firms in the iron and steel industry, particularly those listed on the Borsa İstanbul (BIST). Such assessments are critical for informing strategic decision-making within the sector. This study aims to assess the financial performance of prominent iron and steel companies traded on BIST between 2019 and 2023, employing an advanced multi-criteria decision-making (MCDM) approach. Specifically, an Improved ENTROPY method is combined with the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) to rank the fiscal performance of these enterprises. The findings indicate that EREGL stands out as the highest-performing company in terms of financial metrics over the specified period. The study offers valuable insights into the financial health and operational efficiency of iron and steel firms, providing key information for investors and policymakers in the sector. Additionally, the proposed methodology presents a robust framework for the evaluation of corporate performance in other industries facing similar global challenges.

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Microbial fuel cells (MFCs) represent a promising bio-electrochemical technology with the potential for sustainable energy generation and environmental remediation. These systems exploit the metabolic processes of microorganisms to directly convert organic substrates into electrical energy, providing an environmentally benign alternative to traditional energy sources. The operation of MFCs relies on intricate biological and electrochemical interactions, where microorganisms transfer electrons to electrodes, generating an electric current. MFCs can be classified based on their configuration, electron transfer mechanisms, and operational conditions, each offering distinct advantages and limitations in different contexts. Recent developments in MFC technology have focused on improving power density, stability, and scalability. Innovations in electrode materials, biocatalysts, and reactor design have enhanced energy output, making MFCs more viable for real-world applications. Notably, MFCs show promise in wastewater treatment, as they can simultaneously degrade organic pollutants and generate electricity, thus offering a dual-function solution that contributes to both sustainable energy production and environmental cleanup. Despite these advances, several challenges persist, including the high cost of materials, limited power output, and the need for better integration into existing infrastructure. These issues hinder the widespread adoption of MFCs. Future research must focus on the development of cost-effective materials, the optimization of reactor design, and scaling the technology to achieve commercial feasibility. With continued innovation and refinement, MFCs hold the potential to play a transformative role in renewable energy systems and integrated waste management strategies, contributing to the broader goals of sustainable development.
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