bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulating Emotions through Cogenerative Dialogues to Sustain Student Engagement in Science Internships: A Case Study
Authors: Hsu Pei-Ling
Published: May 2022

Open inquiry learning and student–scientist partnerships are two effective ways of enhancing students’ science learning; however, due to their challenging and intimidating nature, students might encounter emotional breakdowns when engaging with them. To address communicative and emotional issues in high school students’ internships with scientists, this ethnographic case study integrated a pedagogical tool called cogenerative dialogues (cogen), which are conversations cogenerated by different stakeholders to reflect on participants’ experiences and help them reach collective decisions about the rules, roles, and responsibilities that govern their partnerships. Data sources include video recordings of internship activities, video recordings of cogenerative dialogues, students’ journals and interviews, and researchers’ field notes, pictures, and artifacts collected during the internship. Drawing on the emotion regulation framework, I demonstrate how cogen could be used as a powerful tool to reveal emotion suppression, share emotion regulation strategies, and transform negative emotions into positive emotions. The results of this case study show that cogen played an important role in addressing specific issues one at a time and sustaining student engagement throughout the internship program. The implications of cogen for sustainability and organizational health are discussed.
Geodiversity Action Plans as a Tool for Developing Sustainable Tourism and Environmental Education
Authors: Kubalíková Lucie , Bajer Aleš , Balková Marie , Kirchner Karel , Machar Ivo
Published: May 2022

A complex approach to geodiversity and landscape in order to foster geoconservation and develop geotourism and geoeducation is usually more effective than isolated protection and promotion of geoheritage sites without wider context. A Geodiversity Action Plan (GAP) represents a reasonable tool for how to follow these goals in cooperation with local stakeholders. This specific document is not focused only on an inventory of sites of Earth science interest in an area, but encompasses all geodiversity (geological, geomorphological, soil and hydrological features, processes, systems and relationships). As geoconservation often goes hand in hand with education, sustainable tourism and promotion, the GAP includes practical proposals for management and rational use of the area’s geodiversity and geoheritage. This complex approach is needed as it provides a complement to the site-oriented protection or management and, moreover, it can be perceived as coherent with a geoethical approach. The paper presents a case study from Moravian-Slovak border (a central part of Bílé Karpaty/Biele Karpaty Mountains) where the proposal for GAP (including inventory, assessment and management measures) was elaborated together with local authorities, schools and other stakeholders.
Exploring the Spatiotemporal Impacts of the Built Environment on Taxi Ridership Using Multisource Data
Authors: Xie Chen , Yu Dexin , Lin Ciyun , Zheng Xiaoyu , Peng Bo
Published: May 2022

Taxis are an important component of the urban public transportation system, with wide geographical coverage and on-demand services characteristics. Thorough understanding of the built environment affecting taxi ridership can enable transportation authorities to develop targeted policies for transportation planning. Previous studies in this field had few data sources and did not consider the spatiotemporal variability. This study aims to develop an analytical framework for understanding the spatiotemporal correlation between the urban built environment and taxi ridership, which is empirically analyzed in New York City. The built environment is defined through multisource data in terms of density, design, diversity, and destination accessibility. Besides the exploration of travel patterns, the spatiotemporal heterogeneity of taxi ridership is modeled using geographically and temporally weighted regression (GTWR). The result shows that GTWR outperforms ordinary least squares (OLS), geographically weighted regression (GWR), and temporally weighted regression (TWR) in both goodness of fit and explanatory accuracy. More importantly, our study found that land use diversity is negatively correlated with taxi ridership, while transportation diversity is positively correlated with it. A highly accessible road network improves the people’s demand for taxis in the morning rush hours. Moreover, the density of railway stations is positively correlated with taxi ridership on weekdays but adversely on weekends. These findings provide practical insights for urban transportation policy development and taxicab regulation.
The Regional Allocation of Asylum Seekers in Greece: A Multiple Criteria Decision Analysis Approach
Authors: Blouchoutzi Anastasia , Manou Dimitra , Papathanasiou Jason
Published: May 2022

One of the long-term challenges for policy makers in host countries of migrants is the optimal geographical allocation of the migrant population so as to strengthen integration outcomes and serve the crucial goal of social inclusion. The political debate on the appropriate placement policy of newcomers has continued for years after the large-scale inflows of asylum seekers in Greece. This paper focuses on the evaluation of the dispersal policy of asylum seekers in Greece as implemented under the reception and accommodation scheme. Furthermore, it provides decision makers with an alternative dispersal policy framework driven by the integration outcomes of the already established migrant population in the country. The research encompasses Eurostat NUTS 2 annual data for a choice upon availability of the Zaragoza Integration Indicators and the immigrant population indicator for the thirteen Greek regions. The data cover a ten-year period from 2010 to 2019, and they are analysed with the multiple criteria decision-making method PROMETHEE. In addition to desk research, fieldwork has been conducted to illuminate the results of the model. The paper extends the literature on the governance of migration and contributes to the planning of migrant integration policies in their host countries.
Sustainable Alternatives for Tertiary Treatment of Pulp and Paper Wastewater
Authors: Mainardis Matia , Mulloni Silvia , Catenacci Arianna , Danielis Maila , Furlani Erika , Maschio Stefano , Goi Daniele
Published: May 2022

In this work, different alternatives to conventional tertiary treatment of pulp and paper (P&P) wastewater (WW), i.e., physicochemical coagulation-flocculation, were investigated to enhance the environmental and economic sustainability of industrial wastewater treatment. In particular, following a preliminary characterization of secondary effluents, cloth filtration and adsorption were studied, the former by pilot-scale tests, while the latter at laboratory scale. An economic analysis was finally accomplished to verify the full-scale applicability of the most promising technologies. Cloth filtration showed excellent total suspended solids (TSS) removal efficiency (mean 81% removal) but a very limited influence on chemical oxygen demand (COD) (mean 10% removal) due to the prevalence of soluble COD on particulate COD. Adsorption, instead, led to a good COD removal efficiency (50% abatement at powdered activated carbon—PAC—dosage of 400 mg/L). The economic analysis proved that adsorption would be convenient only if a local low-cost (100 €/ton) adsorbent supply chain was established. Ultrafiltration was considered as well as a potential alternative: its huge capital cost (19 M€) could be recovered in a relatively short timeframe (pay-back time of 4.7 years) if the ultrafiltrated effluent could be sold to local industries.
Optimal Power Flow Solution of Power Systems with Renewable Energy Sources Using White Sharks Algorithm
Authors: Ali Mahmoud A. , Kamel Salah , Hassan Mohamed H. , Ahmed Emad M. , Alanazi Mohana
Published: May 2022

Modern electrical power systems are becoming increasingly complex and are expanding at an accelerating pace. The power system’s transmission lines are under more strain than ever before. As a result, the power system is experiencing a wide range of issues, including rising power losses, voltage instability, line overloads, and so on. Losses can be minimized and the voltage profile can be improved when energy resources are installed on appropriate buses to optimize real and reactive power. This is especially true in densely congested networks. Optimal power flow (OPF) is a basic tool for the secure and economic operation of power systems. It is a mathematical tool used to find the instantaneous optimal operation of a power system under constraints meeting operation feasibility and security. In this study, a new application algorithm named white shark optimizer (WSO) is proposed to solve the optimal power flow (OPF) problems based on a single objective and considering the minimization of the generation cost. The WSO is used to find the optimal solution for an upgraded power system that includes both traditional thermal power units (TPG) and renewable energy units, including wind (WPG) and solar photovoltaic generators (SPG). Although renewable energy sources such as wind and solar energy represent environmentally friendly sources in line with the United Nations sustainable development goals (UN SDG), they appear as a major challenge for power flow systems due to the problems of discontinuous energy production. For overcoming this problem, probability density functions of Weibull and Lognormal (PDF) have been used to aid in forecasting uncertain output powers from WPG and SPG, respectively. Testing on modified IEEE-30 buses’ systems is used to evaluate the proposed method’s performance. The results of the suggested WSO algorithm are compared to the results of the Northern Goshawk Optimizer (NGO) and two other optimization methods to investigate its effectiveness. The simulation results reveal that WSO is more effective at finding the best solution to the OPF problem when considering total power cost minimization and solution convergence. Moreover, the results of the proposed technique are compared to the other existing method described in the literature, with the results indicating that the suggested method can find better optimal solutions, employ less generated solutions, and save computation time.
Planning, Optimisation and Evaluation of Small Power-to-Gas-to-Power Systems: Case Study of a German Dairy
Authors: Schmeling Lucas , Buchholz Alexander August Ionnis , Heineke Hilmer , Klement Peter , Hanke Benedikt , von Maydell Karsten
Published: May 2022

In the course of the energy transition, distributed, hybrid energy systems, such as the combination of photovoltaic (PV) and battery storages, is increasingly being used for economic and ecological reasons. However, renewable electricity generation is highly volatile, and storage capacity is usually limited. Nowadays, a new storage component is emerging: the power-to-gas-to-power (PtGtP) technology, which is able to store electricity in the form of hydrogen even over longer periods of time. Although this technology is technically well understood and developed, there are hardly any evaluations and feasibility studies of its widespread integration into current distributed energy systems under realistic legal and economic market conditions. In order to be able to give such an assessment, we develop a methodology and model that optimises the sizing and operation of a PtGtP system as part of a hybrid energy system under current German market conditions. The evaluation is based on a multi-criteria approach optimising for both costs and CO2 emissions. For this purpose, a brute-force-based optimal design approach is used to determine optimal system sizes, combined with the energy system simulation tool oemof.solph. In order to gain further insights into this technology and its future prospects, a sensitivity analysis is carried out. The methodology is used to examine the case study of a German dairy and shows that PtGtP is not yet profitable but promising.
Does Climate Change Affect Rapeseed Production in Exporting and Importing Countries? Evidence from Market Dynamics Syntheses
Authors: Jannat Arifa , Ishikawa-Ishiwata Yuki , Furuya Jun
Published: May 2022

Globally, non-cereal crops such as vegetable oils and their associated products will surpass cereals in demand by 2050, according to the World Bank (WB). Despite being considered an energy-efficient food crop, the production and supply capability of rapeseed is mostly influenced by climate conditions. Aiming in this context, the study explored how temperature and rainfall patterns influence rapeseed production, as well as how rapeseed prices in major trading countries may influence production and consumption patterns in developing countries. To do this, a supply and demand model approach has been employed for major exporting (Canada) and importing countries, i.e., China, the United States (U.S.) along with Bangladesh, a developing nation. The baseline study period was considered from 1991 to 2018, and simulations were performed up to 2040. The findings revealed that the most important effect on rapeseed yield is directly related to changes in temperature, which are positively related to the growing season but negatively related to the maturity stages of rapeseed in all studied countries. Rapeseed exports from Canada are expected to rise by 2040, while imports from China and the U.S. will rise simultaneously. In Canada, the per capita consumption of rapeseed oil is expected to increase from 16 to 24 kg per year between 2019 and 2040. Over the projection period, oil per capita consumption has steadily increased in China, the U.S., and Bangladesh. The relative demand for rapeseed oil is projected to increase by 2060, according to representative concentration pathways (RCPs). Therefore, it is necessary to determine market prices considering the probable climatic effect and increasing market demand for rapeseed to sustain the international market access of trading nations.
Subsidizing Residential Low Priority Smart Charging: A Power Management Strategy for Electric Vehicle in Thailand
Authors: Wangsupphaphol Aree , Chaitusaney Surachai
Published: May 2022

Government policies are crucial factors for supporting the growth of the electric vehicle (EV) industry—a growth that can be encouraged, for example, by subsidization designed to reduce the considerable anxiety stemming from the inconvenience of refueling at public charging stations. Subsidizing low priority charging for residential enables cost-effective load management for example controlling of EV charging power for grid reliability at the off-peak rate for 24 h. This solution provides the convenient recharging of EVs at home and prevents an expensive grid upgradation. To advance our understanding of the EV situation, this research used a regression model to forecast the growth rate of the EV market alongside the EV expansion policies in Thailand. The agreement between a policy and forecasting urges the government to prepare power system adequacy for EV loading. The analysis showed that power demand and voltage reduction in a typical low-voltage distribution system that assumes maximum EV loading constitute voltage violations. To address this limitation, this study proposed a rule-based strategy wherein low priority smart EV charging is regulated. The numerical validation of the strategy indicated that the strategy reduced power demand by 25% and 39% compared with that achieved under uncontrolled and time of use (TOU) charging, respectively. The strategy also limited voltage reduction and prolonged battery life. The study presents implications for policymakers and electricity companies with respect to possible technical approaches to stimulating EV penetration.
Foamed Bitumen Mixtures for Road Construction Made with 100% Waste Materials: A Laboratory Study
Authors: Baldo Nicola , Rondinella Fabio , Daneluz Fabiola , Pasetto Marco
Published: May 2022

Nowadays, budget restrictions for road construction, management, and maintenance require innovative solutions to guarantee the user acceptable service levels respecting environmental requirements. Such goals can be achieved by the re-use of various waste materials at the end of their service life in the pavement structure, therefore avoiding their disposal in landfill. At the same time, significant savings are achieved on natural aggregate by replacing it with such waste materials, improving the economic and environmental sustainability of road constructions. The purpose of this study is to discuss a laboratory investigation about foamed bitumen-stabilized mixtures for road foundation layers, in which the aggregate structure was entirely made up of industrial by-products and civil wastes, namely metallurgical slags such as electric arc furnace (EAF) and ladle furnace (LF) slags, coal fly (CF) ash, bottom ash from municipal solid waste incineration (MSWI), glass waste (GW) and reclaimed asphalt pavement (RAP). Combining these recycled aggregates in different proportions, six foamed bitumen mixtures were produced and investigated in terms of indirect tensile strength, stiffness modulus, and fatigue resistance. The leaching test carried out on the waste materials considered did not show any toxicological issue and the best foamed bitumen mixture’s composition was characterized by 20% of EAF slags, 10% of LF slags, 20% of MSWI ash, 10% of CF ash, 20% of GW, and 20% of RAP. Its mechanical characterization presented a dry indirect tensile strength at 25 °C of 0.62 MPa (well above the Italian technical acceptance limits), a stiffness modulus at 25 °C equal to 6171 MPa, and a number of cycles to failure at 20 °C equal to 6989 for a stress level of 300 kPa.
Environmental Pressures and Value Added Related to Imports and Exports of the Dutch Agricultural Sector
Authors: Donati Franco , Tukker Arnold
Published: May 2022

This study shows the environmental impacts and economic performance due to agricultural trade through The Netherlands. Using the demand-driven input–output model and the database EXIOBASE (2011), we first analysed the environmental impacts and value added directly generated abroad by the agricultural sector through imported final consumption in The Netherlands; we then compared the environmental impacts and value added generated in The Netherlands by the agricultural sector due to exports to other countries. The results show that the Dutch consumption of imported agricultural products had significant greenhouse gas emissions of 19,386 kt CO2-eq, land use of 280,525 km2 and water consumption of 50,373 M.m3, while impacts in The Netherlands due to agricultural exports amounted, respectively, to 13,022 kt CO2-eq, 9282 km2 and 3339 M.m3. At the same time, we found that Dutch agricultural production had a higher value added to pressure ratio than abroad. These differences highlight the great dependency of Dutch final consumption on foreign natural resources, a significant trade imbalance for environmental impacts with relatively smaller economic benefits for countries exporting to The Netherlands. With these results, we suggest that it is of great importance that sustainability policies for the agricultural sector not only address environmental impacts domestically but also impacts and value creation abroad.
Increasing the Livability of Open Public Spaces during Nighttime: The Importance of Lighting in Waterfront Areas
Authors: Rakonjac Ivana , Zorić Ana , Rakonjac Ivan , Milošević Jelena , Marić Jelena , Furundžić Danilo
Published: May 2022

The contemporary way of life influences the forms and time framework of outdoor activities in open public spaces, shifting their focus to nighttime usage. The aim of this study is to demonstrate the limits of existing outdoor lighting design standards and recommendations in terms of livability. As an exploratory case study, the Sava waterfront in New Belgrade, Serbia was chosen. The methodology consisted of theoretical research and specific analysis, which included: (1) mapping the spatial distribution of users during several periods of the day; (2) criteria and indicator network analysis of outdoor lighting quality, and (3) a survey with a questionnaire conducted among the users of the waterfront area. The results showed that lighting design can influence overall open public space usage during nighttime through its parameters. It can affect the spatial distribution of users and their sense of safety and comfort, as well as the duration, frequency, and manner of usage. This study could improve planning and design practices regarding outdoor lighting, enabling more active and inclusive usage of open public spaces, thus increasing the overall livability of spaces and their social sustainability.
Fish Food Production Using Agro-Industrial Waste Enhanced with Spirulina sp.
Authors: Ramírez-Carmona Margarita , Rendón-Castrillón Leidy , Ocampo-López Carlos , Sánchez-Osorno Diego
Published: May 2022

The supply of animal feed is one of the main concerns of producers in the aquaculture industry, including aspects such as the cost of fish flour and its nutritional balance. The aim of this study was the preparation of a pellet-type fish food using powdered Spirulina sp. cultivated as a protein source supplemented with agro-industrial waste, and its evaluation to comply with the necessary parameters for the elaboration of extruded pellets. Spirulina sp. was cultivated in a photobioreactor at a volume of 50 L, separated by decantation and dried. The proximal characterization was 6.79% ± 0.05 moisture, 6.93% ± 0.01 ash, 66.88% ± 0.33 protein, and 5.50% ± 0.26 fat. Subsequently, flours were prepared using cassava leaves, gliricidia leaves, and rice husks. The results for the cohesion showed that the flours obtained to comply with the necessary parameters for the elaboration of extruded food. The fish feed was prepared in pellet form using the formulation for fattening Tilapia: Spirulina sp. (20%), cassava leaf flour (50%), gliricidia leaf flour (20%) and flour of rice husk (10%). Floatation analysis showed that 60% of the pellets floated for more than 40 min, and 80% retained their shape for 4 h. The results show that the obtained product can be used as fish feed, due to the lowest disintegration, together with its great capacity for water absorption and especially, its greater flotage due to the expansion effect, are physic characteristic determinants so that the fish has more time to consume extruded diets and avoid losses.
Does the Belt and Road Initiative Promote Green Innovation Quality? Evidence from Chinese Cities
Authors: Xin Peizhu , Zhao Min , Bai Yang
Published: May 2022

When formulating international economic cooperation agreements, policymakers should consider not only their economic promotion effects but also their impact on green development. This paper is an examination of whether the Belt and Road Initiative contributes to green innovation quality. Objectively assessing the green innovation promotion effects of its implementation is not only important for its completion and improvement in the future, but also to verify whether the Belt and Road Initiative promotes sustainable development in participating regions. A difference-in-difference model was constructed using the data of 291 cities in China from 2008 to 2019. The results show the following: (1) the Initiative has significantly improved the quality of green innovation in cities along the Belt and Road; (2) a series of robustness tests showed that the main results are highly robust; (3) the Belt and Road Initiative has a significant policy spillover effect—while improving the quality of local green innovation, it can also significantly promote the quality of green innovation in surrounding areas. This paper has reference significance for further understanding the policy effect of China’s Belt and Road Initiative and the promotion and strengthening of subsequent policies.
Effect of Tampering on On-Road and Off-Road Diesel Vehicle Emissions
Authors: Giechaskiel Barouch , Forloni Fabrizio , Carriero Massimo , Baldini Gianmarco , Castellano Paolo , Vermeulen Robin , Kontses Dimitrios , Fragkiadoulakis Pavlos , Samaras Zissis , Fontaras Georgios
Published: May 2022

Illegal manipulation (i.e., tampering) of vehicles is a severe problem because vehicle emissions increase orders of magnitude and significantly impact the environment and human health. This study measured the emissions before and after representative approaches of tampering of two Euro 6 Diesel light-duty passenger cars, two Euro VI Diesel heavy-duty trucks, and a Stage IV Diesel non-road mobile machinery (NRMM) agricultural tractor. With tampering of the selective catalytic reduction (SCR) for NOx, the NOx emissions increased by more than one order of magnitude exceeding 1000 mg/km (or mg/kWh) for all vehicles, reaching older Euro or even pre-Euro levels. The tampering of the NOx sensor resulted in relatively low NOx increases, but significant ammonia (NH3) slip. The particle number emissions increased three to four orders of magnitude, reaching 6–10 × 1012 #/km for the passenger car (one order of magnitude higher than the current regulation limit). The tampered passenger car’s NOx and particle number emissions were one order of magnitude higher even compared to the emissions during a regeneration event. This study confirmed that (i) tampering with the help of an expert technician is still possible, even for vehicles complying with the current Euro standards, although this is not allowed by the regulation; (ii) tampering results in extreme increases in emissions.
Insulator Breakage Detection Based on Improved YOLOv5
Authors: Han Gujing , He Min , Gao Mengze , Yu Jinyun , Liu Kaipei , Qin Liang
Published: May 2022

Aerial images have complex backgrounds, small targets, and overlapping targets, resulting in low accuracy of intelligent detection of overhead line insulators. This paper proposes an improved algorithm for insulator breakage detection based on YOLOv5: The ECA-Net (Efficient Channel Attention Network) attention mechanism is integrated into its backbone feature extraction layer, and the effective distinction between background and target is achieved by increasing the weight of important channels. A bidirectional feature pyramid network is added to the feature fusion layer, and large-scale images with more original information are combined to effectively retain small target features. Incorporating a flexible detection frame selection algorithm Soft-NMS (Soft Non-Maximum Suppression) into the prediction layer to re-screen the target frame, thereby reducing the probability of mistaken deletion of overlapping targets. The effectiveness of the improved YOLOv5 algorithm is verified in the actual aerial image dataset, and the results show that the mean Average Precision (mAP) of the improved algorithm is 95.02% and the detection speed FPS (Frames Per Second) can reach 49.4 frames/s, which meets the real-time and accuracy requirements of engineering applications.
Importance of Purchasing Power and Education in the Food Security of Families in Rural Areas—Case Study: Chambo, Ecuador
Authors: Ayaviri-Nina Víctor Dante , Quispe-Fernández Gabith Miriam , Vanegas Jorge Leonardo , Ortega-Mejía Verónica , Cordero-Ahiman Otilia Vanessa
Published: May 2022

Food security is a condition that allows people permanent access to food for a better quality of life; therefore, it is a priority for the economic development of countries. In this context, this research aims to determine the importance of purchasing power and education in the food security of families in rural environments using Chambo canton, Ecuador as a case study. Considering the deductive method, the research is descriptive correlational, with a qualitative and quantitative approach. For data collection, a questionnaire based on the Latin American and Caribbean Food Security Scale was applied to 230 households out of a total of 3585 households. The results showed that the variables of number of income earners and total family income have a high relationship with food security, unlike level of schooling. It was concluded that education does not represent a decisive factor for food security in rural environments, although its incorporation as a variable is important for improving quality of life.
Applying United Nations Sustainable Development Goals, Mt. Cuba Center Gardens with Native Plants and Grows Conservators
Authors: Alford Élan R. , Hoadley Sam , Fazzini Caroline R. , Reilly Laura K. , Highland Amy , Lake Ellen C. , Downing Jeffrey A.
Published: May 2022

Mt. Cuba Center is a botanical garden created with a conservation purpose: to work with native plants and inspire people to become conservators of native habitats. Adherence to this founding mission aligns Mt. Cuba’s activities with 4 of the 17 United Nations Sustainable Development Goals. This article shares aspects of the center’s founding, interpretative plan and content, horticultural research, and conservation programs. We hope that it will inspire the development and implementation of more botanical garden conservation programs that catalyze members, guests, and community partners to participate in and amplify conservation efforts through collective actions. By highlighting the region and its beautiful native flora, Mt. Cuba teaches conservation of native habitats and how to incorporate native plants into home gardens. The garden’s conservation messages are brought to life through interpretive plans, horticultural research, and public engagement. The garden itself acts as a tool to promote conservation by influencing guest attitudes and experiences. The renewal of Mt. Cuba from a fallow cornfield to a thriving ecosystem illustrates that individuals can make a difference. By telling its story and demonstrating accessible conservation actions through its work with native plants, Mt. Cuba aims to transform garden guests into conservators.
Minimizing the Utilized Area of PV Systems by Generating the Optimal Inter-Row Spacing Factor
Authors: Al-Quraan Ayman , Al-Mahmodi Mohammed , Alzaareer Khaled , El-Bayeh Claude , Eicker Ursula
Published: May 2022

In mounted photovoltaic (PV) facilities, energy output losses due to inter-row shading are unavoidable. In order to limit the shadow cast by one module row on another, sufficient inter-row space must be planned. However, it is not uncommon to see PV plants with such close row spacing that energy losses occur owing to row-to-row shading effects. Low module prices and high ground costs lead to such configurations, so the maximum energy output per available surface area is prioritized over optimum energy production per peak power. For any applications where the plant power output needs to be calculated, an exact analysis of the influence of inter-row shading on power generation is required. In this paper, an effective methodology is proposed and discussed in detail, ultimately, to enable PV system designers to identify the optimal inter-row spacing between arrays by generating a multiplier factor. The spacing multiplier factor is mathematically formulated and is generated to be a general formula for any geographical location including flat and non-flat terrains. The developed model is implemented using two case studies with two different terrains, to provide a wider context. The first one is in the Kingdome of Saudi Arabia (KSA) provinces, giving a flat terrain case study; the inter-row spacing multiplier factor is estimated for the direct use of a systems designer. The second one is the water pump for agricultural watering using renewable energy sources, giving a non-flat terrain case study in Dhamar, Al-Hada, Yemen. In this case study, the optimal inter-row spacing factor is estimated for limited-area applications. Therefore, the effective area using the proposed formula is minimized so that the shading of PV arrays on each other is avoided, with a simple design using the spacing factor methodology.
Climate Change Education Challenges from Two Different Perspectives of Change Agents: Perceptions of School Students and Pre-Service Teachers
Authors: Winter Veronika , Kranz Johanna , Möller Andrea
Published: May 2022

Climate change education (CCE) can play an essential role in pushing forward a climate-just transition. However, educational institutions seem to be challenged to equip students and their prospective teachers with what is necessary for them to become multipliers for climate action. This study aims to provide actionable insights on how to harness the untapped potential of CCE, overcome obstacles, and draw conclusions on which adaptations are necessary to improve current CCE settings. We conducted a qualitative questionnaire study using the example of 80 secondary school students (grade 12) and 18 pre-service teachers (PSTs). The results indicated that both cohorts feel inadequately prepared for their role as possible “change agents”, stating that climate change as a topic is given too little time, engagement with practical examples on taking climate action is inadequate, and a superficial examination of the topic takes place. Students as well as PSTs as change agents are not sufficiently supported by educational institutions to exercise their transformative potential due to numerous identified challenges that have to be confronted at a systemic level. Results indicate that especially teacher training programs need to increasingly focus on the professional development of educators in this field.
Performance of Modular-Reinforced Soil-Retaining Walls for an Intercity Railway during Service
Authors: Liang Xiaoyong , Jin Jing , Yang Guangqing , Wang Xizhao , Zhao Quansheng , Zhou Yitao
Published: May 2022

In order to investigate the mechanical behavior of reinforced soil-retaining walls during service, this paper carried out a long-term remote observation test for 6 years on the modular-reinforced soil-retaining wall of the Qingrong intercity railway in eastern China’s Shandong Province. During the construction period, earth pressure boxes, flexible displacement meters, settlement pipes and displacement meters were buried to observe the soil pressure, reinforcement strain, horizontal displacement and settlement of the reinforced earth-retaining wall, respectively, for a long time; then, the results were analyzed to summarize its variation law. The results show that the reinforced earth-retaining wall was stable after one year of construction. It was determined that the strain of reinforcement in each layer decreased with time, culminating in a value of less than 0.88 percent during the 6th year. The maximum horizontal displacement of the wall was 11.43 mm and the maximum settlement of the wall top was 46.77 mm, which were 0.15% and 0.60% of the wall height, respectively. These research results can be applied to the construction and design of reinforced soil-retaining walls in high-speed railways. The effects of the elastic modulus of filler, the tensile modulus of reinforcement and the reinforcement length on the characteristics of the retaining wall were analyzed in the numerical simulation with PLAXIS2D. The results and analysis show: the elastic modulus of filler and reinforcement length have a significant effect on the horizontal displacement of the retaining wall. The results of this experiment can be referenced for engineering projects.
Risk Assessment of Mining Environmental Liabilities for Their Categorization and Prioritization in Gold-Mining Areas of Ecuador
Authors: Salgado-Almeida Bryan , Falquez-Torres Daniel A. , Romero-Crespo Paola L. , Valverde-Armas Priscila E. , Guzmán-Martínez Fredy , Jiménez-Oyola Samantha
Published: May 2022

Mining environmental liabilities (MEL) are of great concern because of potential risks to ecosystems and human health. In this research, the environmental risk (RI) related to MEL existing in three artisanal and small-scale gold-mining areas of Ecuador was evaluated. For this purpose, data of 167 MEL including landfills, mining galleries, tailing deposits, and mineral processing plants from Macuchi, Tenguel–Ponce Enriquez, and Puyango mining areas, were analyzed. The risk assessment related to the presence of waste deposits was carried out based on the methodology proposed by the Spanish Geological Survey. Moreover, the procedure outlined in the Environmental Risk Assessment Guide of the Ministry of Environment of Peru for nonwaste deposits was applied. The highest RI values were identified in Puyango and Tenguel–Ponce Enriquez. Thus, they were both categorized as priority control areas requiring intervention and rehabilitation plans. The MEL that require a high level of intervention include waste deposits and mine entrances associated with potentially toxic elements. Moreover, the point risk maps showed that rivers in the studied areas have a potential pollution risk. This study provides risk levels associated with MEL in mining areas from Ecuador. This information could be used for environmental management and pollution mitigation.
SWOT Analysis of Electrical Discharge Coatings: A Case Study of Copper Coating on Titanium Alloy
Authors: Maddu JagadeeswaraRao , Karrolla Buschaiah , Shaik Riyaaz Uddien , Burdhuhos-Nergis Diana-Petronela
Published: May 2022

The electrical discharge machine (EDM) has been one of the most widely used non-traditional machines in recent decades, primarily used for machining hard materials into various complex shapes and different sizes and, nowadays, used for surface modifications/hard coatings. In this study, the SWOT (strengths, weaknesses, opportunities and threats) of electrical discharge coating was analyzed by conducting a case study. For the purpose of the case study, copper was deposited on the titanium alloy surface (Ti6Al4V). Three electrodes of different copper alloy materials, viz., brass, bronze and copper, were selected for coating the Ti6Al4V surface. Input parameters such as current, pulse-on, pulse-off, flushing pressure and the electrode material were optimized to develop a uniform coating. Experiments were designed according to the L18 orthogonal array, and among them, the samples that showed proper coating, as seen with the naked eye, were selected for morphological and elemental analyses by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX. Further, the output responses, viz., the material deposition rate (MDR), electrode wear rate (EWR), surface roughness (SR), elemental data (copper (Cu) and zinc (Zn)) and coating thickness (CT), were considered for the optimization of coatings. Implementing the Technique for Order Performance by Similarity to Ideal Solution, copper coating with a thickness of 20.43 µm, developed with an MDR with input parameters of 20 A current, 600 µs pulse-on, 120 µs pulse-off, 0.5 bar flushing pressure and the brass electrode, was selected as the optimum coating. The most influential parameters in this coating process were the current and pulse-on time. In this study, a SWOT table was developed to depict the strengths, weaknesses, opportunities and threats of electrical discharge coating.
Study of α-Decay Energy by an Artificial Neural Network Considering Pairing and Shell Effects
Authors: You Hong-Qiang , Qu Zheng-Zhe , Wu Ren-Hang , Su Hao-Ze , He Xiao-Tao
Published: May 2022

We build and train an artificial neural network (ANN) model based on experimental α-decay energy (Qα) data. In addition to decays between the ground states of parent and daughter nuclei, decays from the ground states of parent nuclei to the excited states of daughter nuclei are also included. In this way, the number of samples is increased dramatically. The α particle is assumed to have a spherical symmetric shape. The root-mean-square deviation between the calculated results obtained from the ANN model and the experimental data is 0.105 MeV. It shows a good predictive power for α-decay energy with the ANN model. The influence of different inputs is investigated. It is found that both the shell effect and the pairing effect result in an obvious improvement of the predictive power of the ANN model, and the shell effect plays a more important role. The optimal result can be obtained when both the shell and pairing effects are considered simultaneously. The application of the ANN model in predicting α-decay energy indicates a neutron magic number at N=184 in the superheavy nuclei mass region.
Classical Preisach Model Based on Polynomial Approximation and Applied to Micro-Piezoelectric Actuators
Authors: Liu Van-Tsai , Wing Home-Young
Published: May 2022

In engineering applications, where we demand more and more precision, the modeling of systems with hysteretic nonlinearity has received considerable attention. The classical Preisach model (CPM) is currently the most popular for characterizing systems with hysteresis, and this model can represent the hysteresis with an infinite but countable first-order inversion curve (FORC). The table method is a method used to realize CPM in practice. The data in the table corresponds to a limited number of FORC samples. There are two problems with this approach: First, in order to reflect the timing effects of elements with hysteresis, it needs to consume a lot of memory space to obtain accurate data table. Second, it is difficult to come up with an efficient way to modify the data table to reflect the timing effects of elements with hysteresis. To overcome these shortcomings, this paper proposes to use a set of polynomials instead of the table method to implement the CPM. The proposed method only needs to store a small number of polynomial coefficients, and thus it reduces the required memory usage. In addition, to obtain polynomial coefficients, we can use least squares approximation or adaptive identification algorithms, which can track hysteresis model parameters. We developed an adaptive algorithm for the identification of polynomial coefficients of micro-piezoelectric actuators by applying the least mean method, which not only reduces the required memory size compared to the table method implementation, but also achieves a significantly improved model accuracy, and the proposed method was successfully verified for displacement prediction and tracking control of micro-piezoelectric actuators.
Mechanical Assembly Sequence Determination Using Artificial Neural Networks Based on Selected DFA Rating Factors
Authors: Suszyński Marcin , Peta Katarzyna , Černohlávek Vít , Svoboda Martin
Published: May 2022

In this paper, an assembly sequence planning system, based on artificial neural networks, is developed. The problem of artificial neural network itself is largely related to symmetry at every stage of its creation. A new modeling scheme, known as artificial neural networks, takes into account selected DFA (Design for Assembly) rating factors, which allow the evaluation of assembly sequences, what are the input data to the network learning and then estimate the assembly time. The input to the assembly neural network procedure is the sequences for assembling the parts, extended by the assembly’s connection graph that represents the parts and relations between these parts. The operation of a neural network is to predict the assembly time based on the training dataset and indicate it as an output value. The network inputs are data based on selected DFA factors influencing the assembly time. The proposed neural network model outperforms the available assembly sequence planning model in predicting the optimum assembly time for the mechanical parts. In the neural networks, the BFGS (the Broyden–Fletcher–Goldfarb–Shanno algorithm), steepest descent and gradient scaling algorithms are used. The network efficiency was checked from a set of 20,000 test networks with randomly selected parameters: activation functions (linear, logistic, tanh, exponential and sine), the number of hidden neurons, percentage set of training and test dataset. The novelty of the article is therefore the use of parts of the DFA methodology and the neural network to estimate assembly time, under specific production conditions. This approach allows, according to the authors, to estimate which mechanical assembly sequence is the most advantageous, because the simulation results suggest that the neural predictor can be used as a predictor for an assembly sequence planning system.
Fixed Point of (α,β)-Admissible Generalized Geraghty F-Contraction with Application
Authors: Wang Min , Saleem Naeem , Liu Xiaolan , Ansari Arslan Hojat , Zhou Mi
Published: May 2022

In this paper, we introduce some new types of extended Geraghty contractions, called (α,β)-admissible generalized Geraghty F-contractions, and prove some fixed point results for such contractions in the setting of partial b-metric spaces. Moreover, based on the obtained fixed point results and the property of symmetry, we inaugurate a fixed point result for graphic generalized Geraghty F-contractions defined on partial metric spaces endowed with a directed graph. As an application, we examine the existence of a unique solution to the first-order periodic boundary value by the obtained fixed point result. Moreover, some examples are presented to illustrate the validity of the new results.
Complexity Reduction Approach for Solving Second Kind of Fredholm Integral Equations
Authors: Muthuvalu Mohana Sundaram , Aruchunan Elayaraja , Ali Majid Khan Majahar , Chew Jackel Vui Lung , Sunarto Andang , Lebelo Ramoshweu , Sulaiman Jumat
Published: May 2022

Initially, the concept of the complexity reduction approach was applied to solve symmetry algebraic systems that were generated from the discretization of the partial differential equations. Consequently, in this paper, the effectiveness of a complexity reduction approach based on half- and quarter-sweep iteration concepts for solving linear Fredholm integral equations of the second kind is investigated. Half- and quarter-sweep iterative methods are applied to solve dense linear systems generated from the discretization of the second kind of linear Fredholm integral equations using a repeated modified trapezoidal (RMT) scheme. The formulation and implementation of the proposed methods are presented. In addition, computational complexity analysis and numerical results of test examples are also included to verify the performance of the proposed methods.
Design of a New Dimension-Changeable Hyperchaotic Model Based on Discrete Memristor
Authors: Wei Chengjing , Li Guodong , Xu Xiangliang
Published: May 2022

The application of a memristor in chaotic circuits is increasingly becoming a popular research topic. The influence of a memristor on the dynamics of chaotic systems is worthy of further exploration. In this paper, a multi-dimensional closed-loop coupling model based on a Logistic map and Sine map (CLS) is proposed. The new chaotic model is constructed by cascade operation in which the output of the Logistic map is used as the input of the Sine map. Additionally, the one-dimensional map is extended to any dimension through the coupling modulation. In order to further increase the complexity and stability of CLS, the discrete memristor model is introduced to construct a discrete memristor-based coupling model with a Logistic map and a Sine map (MCLS). By analyzing the Lyapunov exponents, bifurcation diagram, complexity, and the 0–1 test result, the comparison result between CLS and MCLS is obtained. The dynamics performance analysis shows that the Lyapunov exponents and bifurcation diagrams present symmetrical distribution with variations of some parameters. The MCLS has parameters whose values can be set in a wider range and can generate more complex and more stable chaotic sequences. It proves that the proposed discrete memristor-based closed-loop coupling model can produce any higher dimension hyperchaotic system and the discrete memristor model can effectively improve the performance of discrete chaotic map and make this hyperchaotic system more stable.