bluuebunny/crossref_metadata_2025 huggingface dataset:
Semi-Supervised Adversarial Learning Using LSTM for Human Activity Recognition
Authors: Yang Sung-Hyun , Baek Dong-Gwon , Thapa Keshav
Published: June 2022

The training of Human Activity Recognition (HAR) models requires a substantial amount of labeled data. Unfortunately, despite being trained on enormous datasets, most current models have poor performance rates when evaluated against anonymous data from new users. Furthermore, due to the limits and problems of working with human users, capturing adequate data for each new user is not feasible. This paper presents semi-supervised adversarial learning using the LSTM (Long-short term memory) approach for human activity recognition. This proposed method trains annotated and unannotated data (anonymous data) by adapting the semi-supervised learning paradigms on which adversarial learning capitalizes to improve the learning capabilities in dealing with errors that appear in the process. Moreover, it adapts to the change in human activity routine and new activities, i.e., it does not require prior understanding and historical information. Simultaneously, this method is designed as a temporal interactive model instantiation and shows the capacity to estimate heteroscedastic uncertainty owing to inherent data ambiguity. Our methodology also benefits from multiple parallel input sequential data predicting an output exploiting the synchronized LSTM. The proposed method proved to be the best state-of-the-art method with more than 98% accuracy in implementation utilizing the publicly available datasets collected from the smart home environment facilitated with heterogeneous sensors. This technique is a novel approach for high-level human activity recognition and is likely to be a broad application prospect for HAR.
Influence of Embedded Charging Units Characteristics on Long-Term Structural Behavior of E-Roads
Authors: Nodari Claudia , Ketabdari Misagh , Crispino Maurizio , Toraldo Emanuele
Published: June 2022

The use of Electric Vehicles (EV) seems to be a promising solution to achieve a sustainable road transport system. Among the contactless dynamic vehicle charging technologies, the use of Charging Units (CUs)—cement concrete box—embedded into the road pavement seems to be a favorable option. The available scientific papers related to the structural effects of embedding CUs in road pavements consider the CU as a solid box, even if a cavity is needed for the electrical technologies’ accommodation. This is why the current research is aimed at studying electrified roads (e-road) with different CU cavity shapes and dimensions. In detail, pavement structural responses are investigated, as a first step, adopting a Finite Element Model (FEM), and, as a second step, the long-term performances (fatigue cracking/rutting proneness) are evaluated. The study is divided into two phases: the theoretical fatigue/rutting assessment, which allows to calculate the critical load repetitions leading to pavement failure, and an urban case study with the goals of both assessing the theoretical results and computing fatigue/rutting performance with real scale traffic conditions. The outcomes demonstrate that CUs can be used with no significant impacts on the long-term road pavement structural performance, laying the foundation for a future upgrading of the existing urban road networks.
The Effect of Dust Storm on Sea Surface Temperature in the Western Basin of Persian Gulf
Authors: Azad Masoud Torabi , Lari Kamran , Oudi Rana , Sadeghifar Tayeb , Kisi Ozgur
Published: June 2022

A dust storm is one of the costliest and most destructive events in many desert regions. This research investigates the effect of dust storm on sea surface temperature (SST) in the western zone of the Persian Gulf, especially Bushehr Province and its beaches in the years 2008 and 2009. Therefore, some climate and sea parameters such as SST, salinity, air temperature, wind velocity and direction, evaporation, horizontal visibility, sunshine hours and radiation, simultaneously measured in a specific period of time, were analyzed by comparing each of them with satellite data. Sea surface temperature analysis in summer shows that the maximum SST in Persian Gulf along neighbor waters to Bushehr County and central regions in northern section of Persian Gulf is about 34–36 °C. The SST amplitude variation in these places in summer ranges from 28 to 34 °C and when there are dust phenomena, it is from 29.5 to 31 °C. The outcome of this study shows that the SST increases during dusting phenomena and this causes an increase in vapor and as a result a decrease in temperature occurs. On the other hand, vapor increase leads to a growth in the amount and layer of earth’s cloud cover and finally it causes an effective decrease in short-wave sunshine and the temperature and the vapor on surface decrease. As a result, the decrease in sea surface temperature terminates.
Conceptualizing Multiple Stressors and Their Consequences in Agroforestry Systems
Authors: Mustafa Mohammed , Szalai Zita , Divéky-Ertsey Anna , Gál Izóra , Csambalik László
Published: June 2022

The natural environment of crops is exposed to a complex collection of biotic and abiotic pressures. Abiotic stresses cover a diversity of environmental elements that cannot be avoided, such as temperature, drought, salinity, cold, heat, light, and water stress. Biotic stress is caused by living organisms with which plants coexist and interact. Pathogens and herbivores are examples of biotic stressors that can threaten food security and result in significant economic losses. Agricultural production systems differ in the extent of stress towards cultivated crops; agroforestry is considered to provide a protective function against environmental stress. The concept of this review was to assess the impact of environmental change and the atmospheric variability on the plants in agroforestry systems. The application of trees in field crop production has become more and more involved in practice, especially in areas with an extreme climate and unfavorable soil conditions. The main reasons for the rising interest are the effects of climate change, soil degradation, and erosion. Most of the trees are used as hedgerows or farm boundaries, or as scattered planting on the farm to control soil erosion as well as to improve farm productivity, which requires a thorough understanding of each stress element.
Multi-Criteria Decision-Making System for Wind Farm Site-Selection Using Geographic Information System (GIS): Case Study of Semnan Province, Iran
Authors: Yousefi Hossein , Motlagh Saheb Ghanbari , Montazeri Mohammad
Published: June 2022

Selecting the best place for constructing a renewable power plant is a vital issue that can be considered a site-selection problem. Various factors are involved in selecting the best location for a renewable power plant. Therefore, it categorizes as a multi-criteria decision-making (MCDM) problem. In this study, the site selection of a wind power plant is investigated in a central province of Iran, Semnan. The main criteria for classifying various parts of the province were selected and pairwise compared using experts’ opinions in this field. Furthermore, multiple restrictions were applied according to local and constitutional rules and regulations. The Analytic Hierarchy Process (AHP) was used to weigh the criteria, and according to obtained weights, wind speed, and slope were the essential criteria. Moreover, a geographic information system (GIS) is used to apply the weighted criteria and restrictions. The province’s area is classified into nine classes according to the results. Based on the restrictions, 36.2% of the total area was unsuitable, mainly located in the north part of the province. Furthermore, 2.68% (2618 km2) and 4.98% (4857 km2) of the total area are the ninth and eightieth classes, respectively, which are the best locations for constructing a wind farm. The results show that, although the wind speed and slope are the most essential criteria, the distance from power facilities and communication routes has an extreme impact on the initial costs and final results. The results of this study are reliable and can help to develop the wind farm industry in the central part of Iran.
Simulation Analysis of a Double Auction-Based Local Energy Market in Socio-Economic Context
Authors: Beattie Steven , Chan Wai-Kin (Victor) , Wei Zixuan , Zhu Zhibin
Published: June 2022

Local energy markets (LEMs) use online platforms and smart grid technologies to incentivize and coordinate a local supply of spatially-distributed renewable energy resources, which may not be directly controllable by power system operators. Socio-economic values are increasingly noted as prominent motivations for expected LEM users, but socio-economic aspects of user decision-making or market outcomes are not considered in current LEM mechanism design analyses. Here, agent-based simulation is used to analyze expected socio-economic outcomes from LEM operation under a double-sided auction with uniform pricing. The environment is modeled as a virtual LEM platform, operating independently from the underlying power grid. Socio-economic market inputs are produced by income-preference heterogeneous agents, and market outcomes are evaluated by two key socio-economic metrics: energy affordability, and market access. When LEM prices are not restricted to a common range considered by all agents (e.g., between external retail market prices), access disparities may arise; LEM price restriction addresses consumer disparities, but energy affordability gaps are expected to remain. The magnitude of affordability gaps is notably reduced, and bill assistance programs may eliminate remaining gaps, but a mechanism that efficiently realizes socio-economic standards for energy affordability may also reduce expected LEM operation costs. Remaining research gaps are noted, and LEM support for equitable and sustainable energy infrastructure is emphasized.
Impact of Using Social Media Networks on Individual Work-Related Outcomes
Authors: Taboroši Srđana , Popović Jovanka , Poštin Jasmina , Rajković Jelena , Berber Nemanja , Nikolić Milan
Published: June 2022

This paper aims to determine the effects of using social networks on work-related outcomes. Observed work-related outcomes are job satisfaction, organizational commitment, and work performance. The moderating effects of gender and age of respondents on the given relations were also observed. In addition, this paper aims to consider the theoretical and practical implications of such research. The research was conducted in West Balkan countries: Bosnia and Herzegovina, Croatia, Montenegro, North Macedonia, and Serbia. Respondents were employed in organizations in these countries and 313 complete questionnaires were collected. The number of social media networks and somewhat frequency of social media networks usage and the number of photos has a positive effect on individual outcomes of employed persons. Daily time usage, frequency of posting photos, number of groups, and number of groups (active participant) have negative effects on individual outcomes of employed persons. Prolonged use of social media networks (during the day) can especially reduce job satisfaction while joining a large number of groups severely jeopardizes organizational commitment. Active participation in a number of groups significantly reduces salary satisfaction and organizational loyalty among male employees. Excessive use of social media network sites and frequent posting of images can reduce satisfaction with the nature of work and work performance among older employees. The discovered connections and influences have scientific and practical significance, which is explained in the paper.
Use of Fuels in the Productivity of Ecuadorian Companies: Assessment of Their Impact on Climate Change
Authors: Aizaga Miguel , Celi Esteban , Toasa Renato
Published: June 2022

This article aims to analyze the relationship between fuel consumption (gasoline, diesel, and Liquid Petroleum Gas (LPG) and total production in Ecuadorian companies that use some fuel in their processes, in addition to quantifying the CO2 emissions generated by these fuels in 2019. For this purpose, a correlational study of these variables (Pearson’s correlation coefficient) has been made, using statistical data from the ENESEM 2019 Structural Enterprise Survey, prepared by the National Institute of Statistics and Census (INEC). The results show that the relationship between the consumption of Extra gasoline and Ecopais with total production is not significant, while it is in the case of consumption of Super gasoline, Diesel, and LPG. As for CO2 emissions, it is observed that the largest generator is diesel, with almost 4.5 megatons per year, second to gasoline, with a little less than 2 megatons, and finally is LPG, with less than 0.5 megatons. In conclusion, LPG fuel, whose association with total production is the most significant, is the least polluting and in total these business sectors generate almost 7 megatons of CO2 per year of the total 40 megatons generated by the country.
A Bilevel Linear Programming Model for Developing a Subsidy Policy to Minimize the Environmental Impact of the Agricultural Sector
Authors: Ziliaskopoulos Konstantinos , Papalamprou Konstantinos
Published: June 2022

The agro-food industry, while critical for establishing food security, is the most environmentally impactful industry since it causes biodiversity loss and the conversion of natural land to farms and pastures, requires pesticide and fertilizer use as well as high water consumption, and leads to greenhouse gas emissions as well as soil and environmental degradation. This impact can be mitigated through proper policy design. Environmental policy in agriculture, however, is inherently complex, due to the conflict between actors in the system, namely policy makers and farmers. This article introduces a bilevel linear programming (BLP) approach for the development of subsidy policies with the upper-level objective being the minimization of the environmental impact of the agricultural sector. Both levels of the model are formulated as linear programs and by considering the Water-Energy-Food-Climate Nexus, a general-purpose model is introduced. The methodology of the model formulation is spelled out. Finally, different approaches for fine tuning the BLP model are discussed in order to adjust it to each case study’s needs, and the model is applied to the case study of the region of Thessaly, Greece.
The Π-Formed Diaphragm Wall Construction for Departure and Reception of Shield Machine
Authors: Huang Rui , Hu Jun , Pan Jingbo , Wu Yuwei , Ren Xingyue , Zeng Dongling , Wang Zhixin , Wang Shucheng
Published: June 2022

In the design of shield tunnels, it is important to determine the structure of the diaphragm wall in order to achieve the required retaining wall structure pattern. In this paper, the stabilization effect of a new diaphragm wall structure (Π-formed diaphragm wall) is investigated based on model experiments and numerical simulations. By varying the length of the wing wall and its angle to the end wall, it is possible to discuss the effect of different styles of Π-formed diaphragm wall on the support of the soil behind the wall during the departure and reception of the shield machine, the effect of the wing wall on the internal force distribution of the diaphragm wall generated during excavation, the effect of the excavation of the shield machine on the internal force distribution of the diaphragm wall, and the ground settlement during the departure and reception of the shield machine in different construction stages. Π-formed diaphragm walls can effectively support the soil behind the wall and reduce the major principal stresses generated during excavation. The maximum value of the major principal stress in the wing wall of the Π-formed diaphragm wall increases with the length of the wing wall, and the damage to the concrete of the diaphragm wall tends to occur on the outside rim of the wing wall.
Rethinking the Campus Experience in a Post-COVID World: A Multi-Stakeholder Design Thinking Experiment
Authors: Victorino Guilherme , Bandeira Rita , Painho Marco , Henriques Roberto , Coelho Pedro S.
Published: June 2022

In a post-COVID world, rethinking the campus experience is critical for defining new pedagogical strategies. As higher education moves toward more student-centred action learning models, university leaders should engage in democratic design methods that empower students and professors. Design thinking (DT) is a user-centred design approach that can aid in the creation of future learning environments. While DT has been used in innovative space design, we know little about how students, professors, and other community members can act as codesign partners. To understand their role in codesign and how their experiences are incorporated into new building design decisions, we need a conceptual model. To develop this model, we examined a case study of the evolutionary co-design process of a new building for a leading information management school in Europe. Using the concept of three phases of design thinking defined by Brown (2009): Inspire, Ideate, and Implement, we collaborated with a group of 50 design thinking students and more than 500 members of the community representing different stakeholders, to create new spaces and rethink the learning experience. Our discussion will centre on the creation of a participatory design thinking model that positions students as design partners alongside university decision makers. The findings conclude that, by applying design thinking methods, it was possible to unveil new dimensions of the success of future campuses that go beyond the building design. Creating meaningful learning spaces that inspire creativity and critical thinking requires an alignment between human centred design, organizational change management and new pedagogical strategies.
Evolution and Driving Mechanism of Tourism Flow Networks in the Yangtze River Delta Urban Agglomeration Based on Social Network Analysis and Geographic Information System: A Double-Network Perspective
Authors: Wang Yuewei , Xi Mengmeng , Chen Hang , Lu Cong
Published: June 2022

This study’s purpose was to analyze the network structural characteristics, nodal roles, spatial structure, and evolution laws from the dual network perspective, and apply the Quadratic Assignment Procedure (QAP) to conduct correlation analysis and regression analysis on the influencing factors of tourism flow networks in the Yangtze River Delta urban agglomerations. Using a mixed-method of social network and spatial analysis, Ucinet and ArcGIS software were used to comprehensively analyze the nodes in the travel routes covered in travel notes. The results show that the density of tourism flow network increases on the whole, while the spatial difference decreases, and the overall network density value is much lower than the average of the network density of provinces. Degree centrality, closeness centrality, betweenness centrality and the core–periphery structure analysis were used to examine the tourism function, distribution function, connection function and the position of nodes in the network, and nodes were divided into various types of roles according to their function. Meanwhile, the role changes of each node in different periods were also investigated. This study also builds an evaluation model of the influencing factors of the evolution of tourism flow network structure and uses QAP to find that the tourism network is affected by factors such as tourism resource endowment, transportation convenience, economic development level, tourism reception and service capacity. The research results are helpful for the Chinese government and tourism enterprises to understand the spatial behavior of tourists and its evolution rules, and to clarify the role and status of node cities in the tourism flow network and their influencing factors. It is of great significance for the formulation of joint marketing measures and promotion of the sustainable development of tourism in the Yangtze River Delta urban agglomeration.
The Dynamic Behaviour of a Binary Adsorbent in a Fixed Bed Column for the Removal of Pb2+ Ions from Contaminated Water Bodies
Authors: Harripersadth Charlene , Musonge Paul
Published: June 2022

In the search for a technically efficient and abundant adsorbent in water treatment processes, a bio-composite adsorbent derived from agricultural wastes has been identified as a potential candidate. In this study, eggshells and sugarcane bagasse were combined in varied proportions (1:0, 1:3, 1:1, 3:1 and 0:1) and applied as biosorbents in a lab-scale adsorption column. The effect of bed depth (4–12 cm) of the biosorbents was investigated which enabled the prediction of breakthrough curves for the removal of Pb (II) ions. The life span of the column was extended by increasing the bed depth of the column. The binary adsorbent of 1:3 weight ratio of <75 µm particle size showcased the highest removal efficiency of 91% at a bed depth of 12 cm. The mass transfer zone (MTZ) increased with increasing bed depth with a minor portion of the bed left unused, signifying that the process was highly efficient. The Thomas model constant, KTh, decreased with increasing bed depth with the maximum amount of Pb adsorbed being 28.27 mg/g. With the Yoon–Nelson model, KYN decreased with an increase in τ as the bed height increased. In this study, a novel approach was adopted where the proposed methodology enabled the use of a bio-composite adsorbent in heavy metal removal. The findings of this research will aid in the design and optimisation of the pilot-scale operation of environmentally friendly treatment options for metal laden effluent.
Construction Quality Evaluation of Large-Scale Concrete Canal Lining Based on Statistical Analysis, FAHM, and Cloud Model
Authors: Li Qingfu , Guo Lixin , Zhou Huade
Published: June 2022

As an important component of water conservancy infrastructure, canals help improve the uneven distribution of regional water resources. However, in their construction and operation processes, which are affected by a variety of complex factors, canal linings often produce various problems that greatly reduce their overall quality and lead to water resources being wasted. To evaluate and determine the factors and key procedures affecting the construction of concrete canal linings so as to improve their quality, an evaluation mechanism based on statistical analysis, the fuzzy attribute hierarchical model (FAHM), and the cloud model is proposed in this paper. Using this method, we first determine the problems affecting the construction quality of canal linings through statistical analysis, through establishing a questionnaire based on these factors; then, we use FAHM to identify the main quality problem factors; finally, we use the cloud model to analyze the overall construction quality of concrete canal linings. The quality evaluation and key construction procedures are determined, and a case study is conducted taking a canal lining project in China as an example, for which the final evaluation result is grade II. At the same time, a comparative study is carried out using the AHP and cloud models. The results indicate that the proposed method is more reasonable and feasible than existing methods, thus laying a foundation for the follow-up quality control of canals.
Teachers’ Autonomy-Supportive Behaviour and Learning Strategies Applied by Students: The Role of Students’ Growth Mindset and Classroom Management in Low-SES-Context Schools
Authors: Brandisauskiene Agne , Buksnyte-Marmiene Loreta , Daugirdiene Ausra , Cesnaviciene Jurate , Jarasiunaite-Fedosejeva Gabija , Kemeryte-Ivanauskiene Egle , Nedzinskaite-Maciuniene Rasa
Published: June 2022

This study explored a moderated mediation model, which is based on the assumption about the direct relationship between teachers’ autonomy-supportive behaviours and students’ learning strategies and via perceived classroom management as well as the effect of growth mindset for the relationships between (1) teachers’ autonomy-supportive behaviours and learning strategies applied by students and (2) perceived classroom management and learning strategies applied by students. Data were collected from 23 secondary schools in municipalities in Lithuania with low SES (socioeconomic status) contexts (N = 581 students). The results showed that teachers’ autonomy-supportive behaviours are directly and positively related to the increased use of learning strategies applied by the student. The perceived classroom management mediates the relationship between teachers’ autonomy-supportive behaviours and learning strategies applied by the students. In this case, we have an inconsistent mediation, so the mediator acts as a suppressor (the indirect path through mediator is negative, while the direct is positive). The growth mindset does not moderate the relationship between perceived teachers’ autonomy supportive behaviours and the students’ use of learning strategies, but growth mindset moderates the relationship between perceived classroom management and learning strategies applied by the student. For students with a lower or moderate growth mindset, greater perceived classroom management is related to the lesser use of learning strategies. However, for those with a higher growth mindset, greater perceived classroom management is related to greater use of learning strategies. This study contributes to the understanding of the importance of teachers’ behaviours for students’ learning by focusing on classroom management and growth mindset.
The Spatial Effect of Financial Innovation on Intellectualized Transformational Upgrading of Manufacturing Industry: An Empirical Evidence from China
Authors: Zhou Juanmei , Cui Fenfang , Wang Wenli
Published: June 2022

Financial innovation is a powerful source to promote the intellectualized transformation and upgrading of the manufacturing industry. At present, the influence mechanism behind the impact of financial innovation on the manufacturing industry is still unclear and lacks quantitative analysis. This paper selects the representative indicators to study the spatial effect of financial innovation on the intelligent transformation and upgrading of the manufacturing industry based on China’s provincial panel data from 2008 to 2019 by using entropy method, the DEA model, and the spatial econometric model. The results show the following: (1) the overall level of the intellectualized transformation and upgrading of the manufacturing industry has gradually improved, but the spatial distribution is uneven, which has a strong spatial correlation with financial innovation; (2) according to the estimation of the spatial Dobbin model, financial innovation has a significant positive spillover effect on the intellectualization of the manufacturing industry, not only in the region in which it is located, but also in adjacent regions, and the former is greater than the latter; (3) consumption demand, capital allocation, and technological innovation are the three main mediating mechanisms. Finally, according to the findings, we put forward some suggestions and conclusions. This paper provides a positive reference for further promoting the intelligent upgrading of the manufacturing industry from the perspective of financial innovation.
Graphic Engineering in the Sustainable Preservation of the Municipal Heritage of Montilla (Cordoba, Spain) from the 18th Century: Master Builder Vicente López Cardera in Montilla
Authors: Chacón-Ledesma Lucía , Calvo-Serrano María-Araceli , Montes-Tubío Francisco de Paula , Mesas-Carrascosa Francisco-Javier , Triviño-Tarradas Paula
Published: June 2022

The change of territorial organisation in the 18th century in Spain was strongly related to the preservation of the local heritage. Academic architects, military engineers, and master builders coexisted to carry out the design and management of municipal construction works. The evolution of the figure of the master builder and the confrontation with architects and the guilds since the creation of the Royal Academy of Fine Arts of San Fernando posed an inflection point in this aspect. The first aim of the present study was to highlight the figure of Vicente López Cardera, master builder in the Council and Diocese of Córdoba between the late 18th century and the early 19th century, through his work on the municipal interventions in the maintenance of the construction works and infrastructures in Montilla (Córdoba, Spain) around the year 1794. The second aim of the study was to emphasise the role of graphic engineering in the conservation of municipal heritage in the Modern Age through the study of drawings and plans provided by him in the analysed documentation. His thinking in the approach to these works fits with the ideas of social hygienic improvements that began with the Enlightenment as well as with the concept of sustainable development in culture; hence, his work is relevant in the sustainable development planning of cities in the present. With this study, missing heritage elements are also revealed, opening future lines of research that lead to their virtual reconstruction and the promotion of tourism in rural areas.
Green Retrofitting Simulation for Sustainable Commercial Buildings in China Using a Proposed Multi-Agent Evolutionary Game
Authors: Wang Sheng-Yuan , Lee Kyung-Tae , Kim Ju-Hyung
Published: June 2022

Green retrofit is regarded as an effective environmental measure to reduce greenhouse gas emissions in high energy-consuming commercial buildings. However, the current retrofitting rate of complex structures is lower than the expected rate. This study proposed a method of stimulating the interaction of multiple agents (government, developers, and occupants) involved in the green renovation of China’s commercial buildings. To this end, the evolutionary game theory was applied to determine the multiple interaction mechanism of the behaviors of the agents, after which the key factors affecting the contrasting behavior of developers and occupants were demonstrated, and a sensitivity analysis was performed to distinguish detailed set parameters. The major results observed are as follows: (1) occupants are less sensitive to varied conditions owing to their vulnerable economic scale, meaning that a more friendly policy environment is essential to facilitate their support; (2) government financial support, such as subsidies or compensation costs, can strongly induce more positive behavior in developers to promote green retrofit; and (3) life-cycle awareness of developers should be improved as a reasonable energy-saving performance can act as a key motivating factor to support green renovation. This research provided a comparative perspective to that of a public–private partnership model.
Sustainable and Low-Cost Hemp FRP Composite Confinement of B-Waste Concrete
Authors: Joyklad Panuwat , Yooprasertchai Ekkachai , Rahim Abdur , Ali Nazam , Chaiyasarn Krisada , Hussain Qudeer
Published: June 2022

Each year, massive amount of construction waste is generated that needs proper attention in terms of its disposal without deteriorating surrounding environment. A significant portion of this waste comprises bricks. Besides, large number of new construction works are resulting in the depletion of natural resources rapidly. Intuitively, a sustainable solution demands to consume this construction waste in the best way possible. This study targeted brick waste as a potential material to be used as a partial replacement of natural aggregates in structural concrete. It has been known that the concrete constructed with recycled brick aggregates possesses substandard mechanical properties. Traditionally, synthetic FRPs are known to strengthen recycled aggregate concrete. However, recognizing high costs associated with them, this study proposed the use of natural hemp fiber ropes to strengthen recycled aggregate concrete constructed with brick aggregates. To assess the efficacy of hemp ropes in strengthening mechanical properties of the concrete with coarse aggregates partially replaced with recycled brick aggregates (B-waste), an experimental framework was conducted. Sixteen cylindrical specimens were tested in two groups depending upon the concrete strength. Within each group, 2 specimens each were strengthened with 1, 2, and 3 layers of hemp fiber ropes. Axial monotonic compressive loading was applied to each specimen. Results revealed that hemp fiber ropes significantly improved ultimate compressive strength and the corresponding strain. A substantial improvement in axial ductility was observed. For the sake of performance-based non-linear modelling, accurate constitutive modelling at material level is necessary. For this purpose, several existing analytical stress-strain models were tested in this study to predict ultimate confined compressive strength and strain. It was found that several models predicted confined compressive strengths with reasonable accuracy. However, very few models were able to predict confined peak strain with good accuracy.
Sustainable Sand Substitutes in the Construction Industry in the United States and Canada: Assessing Stakeholder Awareness
Authors: Zadeh Adel A. , Peng Yunxin , Puffer Sheila M. , Garvey Myles D.
Published: June 2022

The United Nations has declared a global sand crisis, called for reduced sand consumption, and proposed solutions to address the crisis, including adopting sustainable substitutes for sand. The construction industry is a major consumer of sand, yet a recent study found a very low level of awareness by stakeholders of the crisis. The purpose of this study is to assess the familiarity of construction industry stakeholders with 27 sand substitute materials, grouped into five components that emerged from a factor analysis. Data were collected using a survey designed by the authors. Respondents consisted of 156 construction industry professionals located in 35 US states and 7 Canadian provinces. Stakeholders were classified according to a framework considering the level of power and interest of each stakeholder in sustainable construction projects. Hypotheses of no differences in awareness for two types of stakeholder groups were generally supported. First, no differences were found for decision makers responsible for ordering sand vs. non-decision makers. Second, for professional roles, academics were more familiar with some substitutes than those in other roles. The article concludes with implications for research and practice, with recommendations on how to increase awareness of sand substitutes among stakeholders in the construction industry.
An Efficient Approach to Investigate the Tradeoff between Double Handling and Needed Capacity in Automated Distribution Centers
Authors: Alnahhal Mohammed , Salah Bashir , Ruzayqat Mohammed
Published: June 2022

Sustainable techniques in distribution centers, such as automation that reduces the land area needed, can be utilized. Automated Storage and Retrieval Systems (AS/RS) are used to efficiently manage the flow of pallets and carton cases in distribution centers. There are two types of AS/RS: one for pallets and another type for cases that are depalletized from pallets. Further enhancements on the system are obtained by investigating both warehouses together. This paper investigates an efficient approach that directly affects the conceptual design of automated distribution centers for the purpose of reducing the total costs. The tradeoff between the throughput (defined by the level of double handling) and warehouse capacity is investigated in this study by finding the best lot sizing rules for different classes of products (A, B, and C). These rules are to determine the method of moving carton cases from the first warehouse to the second one. The number of stacker cranes is determined based on the found throughput. The effect of double handling of pallets on the design is considered for the first time in this study. Analytical formulas and simulation were used to find the throughput and capacity based on the mentioned lot sizing rules. Then, an integer nonlinear model was developed to optimize the system. According to the results of the assumed data, the model can save up to 19.5%. The costs of stacker cranes were found to account for approximately 78.7% of the total costs in the best solution found. A decision support system has been developed to help decision makers find an efficient design of distribution center.
Valorization of Agricultural Side-Streams for the Rearing of Larvae of the Lesser Mealworm, Alphitobius diaperinus (Panzer)
Authors: Gourgouta Marina , Rumbos Christos I. , Michail Vasilios , Athanassiou Christos G.
Published: June 2022

During the last decade, insects have shown up as a promising answer to the increasing animal protein demand for a continuously growing human population. A wide spectrum of substrates of plant origin can be currently used as insect feed; the sustainability of insect rearing though greatly increases when organic side-streams and wastes are valorized and upcycled through their bioconversion with insects. Additionally, the exploitation of low-cost organic residues as insect feed can also significantly suppress the rearing cost and, consequently, the price of the insect meal. In this context, the aim of our work was to evaluate organic side-streams, generated through several agro-industrial processes, as feeding substrates for the larvae of the lesser mealworm, Alphitobius diaperinus. In a laboratory trial, eleven agricultural side-streams were provided to larvae singly to assess their potential to support complete larval development, whereas in the second trial, larvae were fed two groups of isoproteinic diets consisting of the side-streams that performed well in the first trial. Our results showed the suitability of several agricultural side-streams as feed for A. diaperinus larvae, e.g., barley by-products (classes I and II), sunflower meal, cotton cake and oat sidestream, which, when fed singly, efficiently supported larval growth, resulting in high survival rates and final larval weights, comparable to the control. Similarly, several of the side-streams-based diets tested were shown to be suitable for A. diaperinus rearing. These results aim to contribute to the utilization of agricultural side-streams singly or in composed diets for the rearing of A. diaperinus larvae.
A General-Equilibrium Model of Labor-Saving Technology Adoption: Theory and Evidences from Robotic Milking Systems in Idaho
Authors: Du Xiaoxue , Tejeda Hernan , Yang Zhengliang , Lu Liang
Published: June 2022

Automatic milking systems (AMSs) have become increasingly common in the US in the past few years. Recent surveys from Idaho, one of the largest dairy-producing states, as well as from other states and countries, suggest that: 1. among farms adopting robotic milking systems, few are reporting less labor usage after adopting this labor-saving technology; 2. small farms rather than large farms are adopting (or more interested in adopting) robotic milking systems. In this article, we propose a series of new modeling strategies, which introduces the role of general-equilibrium effects to explain these new stylized facts. We show that: first, farms adopting labor-saving technology may, in fact, use more labor to compensate for the loss in the value of labor; second, when smaller farms experience more labor efficiency gains or value their leisure time (or off-farm income) more, they are more likely than larger farms to adopt the new technology. We contribute to the technology-adoption literature in two important ways. First, to our knowledge, this is the first article that introduces general-equilibrium effects to the technology-adoption literature. Second, this is also the first article that provides a theoretical perspective to explain the stylized facts in the adoption of robotic milking systems.
Environmental Risk Assessment of the Zhengrunzhou Water Source under the Influence of Oil Spill Accidents at the Wharf Group
Authors: Zhou Qi
Published: June 2022

To compensate for the research defects of strong subjectivity in determining oil spill amount, insufficient consideration of wharf distribution, and incomplete indexes for reflecting the influence degree of oil spill accidents on water sources, and to enhance the supervision efficiency of the supervision department, this paper constructs a risk assessment system of water sources under the influence of the wharf group. The system includes a wharf group division method considering the wharf distribution situation; the calculation method of oil spill amount at wharves considering the oil tank capacity of main ship types and the production supervision risk at the wharves; the calculation method of the oil spill amount at the wharf group considering the wharf number, distribution density, production supervision risk and wharf oil spillage; the determination method for the influence degree of oil spill at the wharf group on the water sources and judgment method of supervision level at the wharf group, which takes the arrival time of oil slicks, the duration of over-standard petroleum concentration and the maximum over-standard multiple of petroleum concentration at the water intake as indexes; the method of determining the risk of oil spill accidents at the water source considering the cumulative effect of oil spill at the wharf group on the risk of the water sources; and the environmental risk assessment method of water sources considering oil spill accident risk and the anti-risk ability. Applying this system to the environmental risk assessment of the Zhengrunzhou water source in Zhenjiang City, we discovered that the flow field, wind field, oil spill location and oil spill amount were correlated with the influence degree of oil spill accidents on water sources, for which the flow field demonstrated the strongest correlation, while the wind field presented the weakest. The supervision level of the wharf group is mainly sub-key or non-key levels, but the level of the wharf group SD07 is approximate to the key supervision level during rising tide. Due to the strong anti-risk ability of the Zhengrunzhou water source, the environmental risks of the Zhengrunzhou water source under different working conditions are scarcely different and belong to the medium-risk level.
How Surface Irrigation Contributes to Climate Change Resilience—A Case Study of Practices in Mexico
Authors: Chávez Carlos , Fuentes Sebastián , Fuentes Carlos , Brambila-Paz Fernando , Trejo-Alonso Josué
Published: June 2022

Climate change has brought increased temperatures and decreased rainfall on a global scale; however, population growth requires greater volumes of water and food each year that must be supplied in one way or another. In Mexico, application efficiencies in gravity irrigation are below 50%. Although in recent years the decision has been made to change to pressurized irrigation systems to increase the efficiency of water use, border or furrow irrigation is still the most widely used in agriculture. In this work, we show that with a methodology developed and applied in these systems, application efficiencies greater than 90% were obtained, while the Water Use Efficiency (WUE) increased by 27, 38 and 47% for the three crops where it was applied: sorghum, barley, and corn, respectively. Irrigation times per hectare and applied irrigation depths decreased by more than 30%, representing increased irrigation efficiencies and WUE. Finally, the water savings obtained can mitigate water scarcity in cities.
Supply Chain Diversification, Digital Transformation, and Supply Chain Resilience: Configuration Analysis Based on fsQCA
Authors: Yin Weili , Ran Wenxue
Published: June 2022

To determine the influence of COVID-19 on supply chains, previous research has examined the impact of supply chain diversification and digital transformation on supply chain resilience, but few studies have integrated these two aspects to understand their impact on supply chain resilience. Given this, our study implements the fuzzy set qualitative comparative analysis (fsQCA) method to investigate the influence of supply chain diversification (supply base diversification and customer base diversification) and digital transformation (digital transformation depth and breadth) on supply chain resilience. Using data from 191 listed manufacturing firms, it is shown that the dimensions of supply chain diversification and digital transformation do not have the necessary conditions to achieve high supply chain resilience, while the analysis of sufficient conditions shows that three paths can achieve high supply chain resilience—namely, those driven by digital transformation, supply chain diversification, and supplier centralization and customer base diversification. This study demonstrates the numerous and complex linkages between antecedent and outcome, and firms can choose the path that is best for them to improve supply chain resilience based on their size, degree of digital transformation, and supply chain diversification.
Challenges of the Coronavirus Pandemic as an Opportunity for Sustainable Digital Learning in Vocational Education and Training (VET)
Authors: Seyffer Silke , Hochmuth Melanie , Frey Andreas
Published: June 2022

In addition to restrictions in training companies, vocational schools were also closed due to the coronavirus pandemic in Germany. After the unexpected first lockdown, it was the challenge of all those involved to draw lessons from the emergent weaknesses in the system and to prepare for further school closures. These preparations primarily involved shifting to digital learning platforms. This article uses a simple and easy to understand research design and focuses from a practical point of view on the results of a quantitative online survey conducted by the University of Applied Labour Studies Mannheim among 143 apprentices in southern Germany on the differences between the first and second school closures with regard to live communication with teachers, attention to apprentice concerns by the vocational school, access to digital devices, and the use of these devices. The results of the survey show that, according to the apprentices’ assessments, the vocational schools were able to improve live communication as well as better attend to the apprentices’ concerns between lockdowns. In addition, the apprentices were able to improve their own digital devices and competencies and, to a large extent, make up for deficits. They were better able to use digital devices and software during the second school closure compared to the first. Gender differences were observed. However, despite significant improvements, there is still a need to modernize and innovate, which should be considered in future digital developments at schools.
A Variation on Inequality for Quaternion Fourier Transform, Modified Convolution and Correlation Theorems for General Quaternion Linear Canonical Transform
Authors: Bahri Mawardi , Abdul Karim Samsul Ariffin
Published: June 2022

The quaternion linear canonical transform is an important tool in applied mathematics and it is closely related to the quaternion Fourier transform. In this work, using a symmetric form of the two-sided quaternion Fourier transform (QFT), we first derive a variation on the Heisenberg-type uncertainty principle related to this transformation. We then consider the general two-sided quaternion linear canonical transform. It may be considered as an extension of the two-sided quaternion linear canonical transform. Based on an orthogonal plane split, we develop the convolution theorem that associated with the general two-sided quaternion linear canonical transform and then derive its correlation theorem. We finally discuss how to apply general two-sided quaternion linear canonical transform to study the generalized swept-frequency filters.