bluuebunny/crossref_metadata_2025 huggingface dataset:
A Variable Selection Method for Small Area Estimation Modeling of the Proficiency of Adult Competency
Authors: Ren Weijia , Li Jianzhu , Erciulescu Andreea , Krenzke Tom , Mohadjer Leyla
Published: July 2022

In statistical modeling, it is crucial to have consistent variables that are the most relevant to the outcome variable(s) of interest in the model. With the increasing richness of data from multiple sources, the size of the pool of potential variables is escalating. Some variables, however, could provide redundant information, add noise to the estimation, or waste the degrees of freedom in the model. Therefore, variable selection is needed as a parsimonious process that aims to identify a minimal set of covariates for maximum predictive power. This study illustrated the variable selection methods considered and used in the small area estimation (SAE) modeling of measures related to the proficiency of adult competency that were constructed using survey data collected in the first cycle of the PIAAC. The developed variable selection process consisted of two phases: phase 1 identified a small set of variables that were consistently highly correlated with the outcomes through methods such as correlation matrix and multivariate LASSO analysis; phase 2 utilized a k-fold cross-validation process to select a final set of variables to be used in the final SAE models.
A Comprehensive Review of Path Planning for Agricultural Ground Robots
Authors: Chakraborty Suprava , Elangovan Devaraj , Govindarajan Padma Lakshmi , ELnaggar Mohamed F. , Alrashed Mohammed M. , Kamel Salah
Published: July 2022

The population of the world is predicted to reach nine billion by 2050, implying that agricultural output must continue to rise. To deal with population expansion, agricultural chores must be mechanized and automated. Over the last decade, ground robots have been developed for a variety of agricultural applications, with autonomous and safe navigation being one of the most difficult hurdles in this development. When a mobile platform moves autonomously, it must perform a variety of tasks, including localization, route planning, motion control, and mapping, which is a critical stage in autonomous operations. This research examines several agricultural applications as well as the path planning approach used. The purpose of this study is to investigate the current literature on path/trajectory planning aspects of ground robots in agriculture using a systematic literature review technique, to contribute to the goal of contributing new information in the field. Coverage route planning appears to be less advanced in agriculture than point-to-point path routing, according to the finding, which is due to the fact that covering activities are usually required for agricultural applications, but precision agriculture necessitates point-to-point navigation. In the recent era, precision agriculture is getting more attention. The conclusion presented here demonstrates that both field coverage and point-to-point navigation have been applied successfully in path planning for agricultural robots.
Automatic Vehicle Identification and Classification Model Using the YOLOv3 Algorithm for a Toll Management System
Authors: Rajput Sudhir Kumar , Patni Jagdish Chandra , Alshamrani Sultan S. , Chaudhari Vaibhav , Dumka Ankur , Singh Rajesh , Rashid Mamoon , Gehlot Anita , AlGhamdi Ahmed Saeed
Published: July 2022

Vehicle identification and classification are some of the major tasks in the areas of toll management and traffic management, where these smart transportation systems are implemented by integrating various information communication technologies and multiple types of hardware. The currently shifting era toward artificial intelligence has also motivated the implementation of vehicle identification and classification using AI-based techniques, such as machine learning, artificial neural network and deep learning. In this research, we used the deep learning YOLOv3 algorithm and trained it on a custom dataset of vehicles that included different vehicle classes as per the Indian Government’s recommendation to implement the automatic vehicle identification and classification for use in the toll management system deployed at toll plazas. For faster processing of the test videos, the frames were saved at a certain interval and then the saved frames were passed through the algorithm. Apart from toll plazas, we also tested the algorithm for vehicle identification and classification on highways and urban areas. Implementing automatic vehicle identification and classification using traditional techniques is a highly proprietary endeavor. Since YOLOv3 is an open-standard-based algorithm, it paves the way to developing sustainable solutions in the area of smart transportation.
Evaluation of Urban Sustainability in Cities of The French Way of Saint James (Camino de Santiago Francés) in Castilla y León according to The Spanish Urban Agenda
Authors: Tomatis Francisco , Lozano-Castellanos Luisa F. , García-Navarrete Oscar L. , Correa-Guimaraes Adriana , Wilhelm Maria Sol , Boukharta Ouiam Fatiha , Murcia Velasco Diana A. , Méndez-Vanegas José E.
Published: July 2022

The emblematic French Way of Saint James (Camino de Santiago Francés) crosses towns, cities, and Spanish regions to the Cathedral of Santiago de Compostela (Galicia, Spain), However, where is The French Way of Saint James going with respect to the urban sustainability of its host cities? As each city is unique and urban sustainability favors the revitalization and transition of urban areas, to know where to go, it is first necessary to establish a diagnosis that makes the different urban situations visible. In this article, the behavior of urban sustainability is analyzed in the six host cities of The French Way of Saint James in the Autonomous Community of Castilla y León, a region characterized by its link with the rural environment and its current depopulation problems. The data and indicators used are officially provided by the Spanish Urban Agenda, which, through the normalization of its values, are able to territorialize the SDGs at the local level and reflect the realities of the cities of Burgos, Astorga, Cacabelos, León, Ponferrada, and Valverde de la Virgen. The results make it possible to diagnose and compare these host cities, identifying weaknesses, skills, and opportunities that favor the promotion of action plans, local or joint (favored by The French Way of Saint James), in the multiple aspects of sustainability. In addition, they show that Valverde de la Virgen is the city with the best performance in terms of urban sustainability.
The Role of Design in the CE Transition of the Furniture Industry—The Case of the Italian Company Cassina
Authors: Bruno Davide , Ferrara Marinella , D’Alessandro Felice , Mandelli Alberto
Published: July 2022

The literature on circular economy has highlighted the need for more studies focused on investigating the journey of individual companies in the transition toward sustainable processes. This paper addresses this need by focusing on the furniture design industry, showing how the transition requires the re-organization of knowledge regarding materials, processes, technologies, and product quality. This assumption is demonstrated through the design research activity conducted in 2019–2020 as the first part of broader research by Cassina LAB, a collaboration between Cassina Research and Development Centre and POLI.design of Politecnico di Milano. Based on the analysis of the Italian furniture industry between constraints and opportunities, the aim of the research is to identify critical issues and propose sustainable and circular solutions, tailor-made for Cassina. Through this example, the paper contributes to the literature in two ways. First, it adds to the understanding of how companies are adopting the circular economy paradigm. Secondly, it contributes to defining tools to implement new forms of knowledge of materials and re-design processes to deliver products that are compatible with a circular economy model.
A Tree-Planting Vehicle for Promoting the Sustainable Development of Desert Greening
Authors: Lu Peng , Wu Fan , Lin Yang-Cheng
Published: July 2022

Preventing land desertification is one of the 17 sustainable development goals of the United Nations, which can effectively promote the sustainable development of desert greening. Currently, tree plantation is the most effective way to achieve this goal. However, the existing tree-plantation activities have some imperfections, including low efficiency, labor-intensiveness, challenging environments, and the low survival rate of saplings. Therefore, to contribute to the sustainable development of desert greening, this paper presents a practical desert tree-planting vehicle based on scientific and effective design and evaluation methods. First, based on the survey results, we used the objectives tree method to clarify the design objectives of the tree-planting vehicle. Second, the functional system boundaries of the tree planting vehicle were clarified using the function analysis method. Third, several alternatives were obtained using the finite structure and morphological analysis methods. Finally, an optimal solution was obtained using fuzzy comprehensive evaluation. This optimal design scheme has the characteristics of mechanical automatic planting, a closed cockpit, and large-capacity storage space, which can improve the construction efficiency and labor intensity, thereby contributing to the sustainable development of desert greening.
Green R&D Financing Strategy in Platform Supply Chain with Data-Driven Marketing
Authors: Xia Yanfei , Guo Quan , Sun Hao , Li Ke , Mu Zongyu
Published: July 2022

Platform enterprises can improve green R&D efficiency by data-driven marketing (DDM) activities and can also provide financing assistance to manufacturers. In this context, for a platform supply chain consisting of one manufacturer facing a shortage of green R&D funds and a one third-party platform, this paper develops four game models under two financing channels (bank financing channel and platform financing channel) and two selling modes (agency selling mode and reselling mode). The equilibrium results of different models are derived and compared, and then the choices of selling mode and financing channel from the perspectives of both the manufacturer and the platform are analyzed. The conclusions show that the consumers’ sensitivities to green R&D and DDM activities, as well as service commission fee, are major factors influencing green R&D level and both parties’ choice of selling mode and financing channel. In most cases, a platform financing channel can promote the green R&D level better and is more beneficial to the manufacturer and the platform. Only in a few cases, the two parties prefer the reselling mode and bank financing channel. However, agent selling with bank financing will never be their optimal strategy. There exists four situations in which the manufacturer and the platform can agree on a same strategy on selling mode and financing channel.
Dynamic Response Characteristics and Damage Evolution of Multi-Layer Combined Coal and Rock Mass under Impact Loading
Authors: Li Feng , Sun Runchuan , Zhang Yue , Wang Guanghao , Xiang Guangyou
Published: July 2022

The areas involved in coal and gas outbursts are composed of multi-layer coal and rock mass, in which external dynamic disturbance propagates in the form of stress waves; therefore, reflection, transmission and diffraction occur at the interfaces, resulting in dynamic effects such as reflected tension, convergence and superposition of stress and strain, and sudden changes of reflected and transmitted stress, which are the key factors leading to the outburst. Based on the Split Hopkinson Pressure Bar system, the dynamic time–history changes of stress, strain and strain rate of five-layer combined coal and rock mass were studied under impact loading. The results show that the time–history curves of stress and strain could be divided into five stages and that of strain rate three stages; the dynamic curves of the five stress–strain stages were significantly different between high-velocity and low-velocity impact. It was hypothesized that under high-speed impact loading, the mechanical anisotropy of combined coal and rock mass at the linear elastic stage tends to be isotropic. Based on ANSYS LS-DYNA, the damage evolution and failure process of five-layer combined coal and rock mass were simulated and analyzed under impact loading. It is concluded that the initial positions of damage of each layer were located at the circle center and its vicinity; radial cracks were mainly formed under low-speed impact loading, and circumferential cracks were mainly formed under high-speed impact loading. In the propagation and action of loading and unloading waves, the “weak layer” was damaged first by tensile stress and formed a free surface, and the subsequent loading waves were reflected on the free surface to form unloading waves and tensile stress, resulting in damage and spalling in multi-layer coal and rock mass.
Restoration of Land Acquired for Resettlement and the Fast-Track Land Reform Programme in Zimbabwe
Authors: Runganga Raynold , Njoroge Winnie , Mishi Syden
Published: July 2022

This paper examines the effect of the land reform program on the production of main agricultural crops, which are maize and soyabean, in a bid to deduce the implications of the possible restoration of land acquired for resettlement in Zimbabwe. The interest of this paper is in response to the new legislation by the Government of Zimbabwe under which former farm holders may apply for restoration of title to the piece of agricultural land that was compulsorily acquired from them for resettlement during the 2000 Fast-Track Land Reform Programme (FTLRP). Contrary to cross-sectional studies done before, this study applied the Ordinary Least Squares estimation technique on time series data covering the period 1980–2019. The results show that the period after the land reform has lower maize and soyabean output per hectare compared to the period before land reform. The findings imply that the FTLRP disrupted production, which has never been restored to prior output levels; this points to the new government’s interest in the restoration of land to former farm holders to sustain agricultural production, particularly maize and soyabean.
Monitoring Land Use Land Cover Changes and Modelling of Urban Growth Using a Future Land Use Simulation Model (FLUS) in Diyarbakır, Turkey
Authors: Çağlıyan Ayşe , Dağlı Dündar
Published: July 2022

Land use and land cover (LULC) change corresponds to the greatest transformations that occur on the earth’s surface under physical, human and socio-economic geographical conditions. Increasing demand for residential and agricultural lands has been transforming all land classes and this should be investigated in the long term. In this study, we aim to determine LULC change and land use simulation in Diyarbakır with Geographical Information System (GIS) and Remote Sensing (RS) techniques. For this purpose, satellite images from 1984, 2002, and 2020 were classified at different levels by an object-based classification method. Accuracy assessments of the classified images were made and change detection analyses were performed using TerrSet software. The LULC changes were also estimated in different scenarios using a future land use simulation model (FLUS). The results show that natural and semi-natural areas are rapidly disappearing due to urban growth between 1984 and 2020. The results of the land use simulation show that by 2038, while the agricultural, pasture and water bodies will decrease, the built-up areas will increase. It is estimated that the city, which has developed in a west-northwest direction, will expand in the future and grow between Elazığ and Şanlıurfa Boulevard.
Conditions Affecting Wind-Induced PM10 Resuspension as a Persistent Source of Pollution for the Future City Environment
Authors: Linda Jakub , Pospíšil Jiří , Köbölová Klaudia , Ličbinský Roman , Huzlík Jiří , Karel Jan
Published: July 2022

Air pollution by particulate matter (PM) in cities is an ongoing problem with increasing severity. The biggest PM contributors are traffic and domestic fire burning. With the shift towards electromobility and the use of low-emission fuels, attention should be shifted to less mentioned sources of pollution. Such sources of pollution include wind-induced resuspension. This study focuses on determining the threshold wind speed causing the resuspension of particulate matter (TWSR) with aerodynamic diameter smaller than 10 µm. A methodology is introduced that examines how data could be treated to identify its characteristics (for locations where only PM10 data are available). The most significant monitored parameters are air humidity, wind direction, time of the day, and surface type. The characteristic wind speeds causing resuspension are identified in four locations for different times of day. It was proven that at times of intense human activity, particles are lifted by wind more easily. The mean threshold wind speed causing resuspension in the studied urban environment was identified as 1.58 m/s at a height of 2 m above the surface. The wind speeds were also compared with experimental studies of resuspension. The results proved correspondence between the identified wind speeds and the experimental results.
The Spatial Spillover Effect and Its Impact on Tourism Development in a Megacity in China
Authors: Cao Yajun , Liu Jianguo
Published: July 2022

By utilizing the tourism development data of Beijing for the period from 2010 to 2019, this study examined the spatial pattern distribution of tourism development in Beijing using the coefficient of variation and Moran’s I index. In addition, the geographic detector method was employed to explore the impact of tourism resource investment, tourism reception facilities, and urban development level on the spatial pattern of tourism development. The results indicate that the spatial differences in tourism development in various Beijing districts are gradually expanding, mainly focusing on the differences between urban function expansion regions. The number of tourists shows a spatial distribution pattern including a core area, urban function expansion area, ecological conservation area, and new urban development area. The spatial correlation of tourism development increases gradually, and some parts show the spatial correlation form of low–high aggregation. Tourism resource investment, tourism reception facilities, and urban development level all play a significant role in promoting the spatial pattern of tourism development, among which the most obvious role is the interactive effect of tourism reception facilities, star-rated hotels, and openness. Therefore, to improve the development of Beijing’s tourism industry, the government needs to pay attention to the differences in the expansion of urban functions, the degree of contact between regions, the number of tourism reception facilities, and the level of regional openness. The significance of this research is in promoting spatial governance, coordinated development among regions, and the high-quality development of tourism in Beijing, and laying down a foundation for the introduction of spatial collaborative governance policies in other megacities in China.
Control Strategy and Performance Analysis of Electrochemical Energy Storage Station Participating in Power System Frequency Regulation: A Case Study of the Jiangsu Power Grid
Authors: Fang Jicheng , Wang Yifei , Lei Zhen , Xu Qingshan
Published: July 2022

Electrochemical energy storage stations (EESSs) have been demonstrated as a promising solution to mitigate power imbalances by participating in peak shaving, load frequency control (LFC), etc. This paper mainly analyzes the effectiveness and advantages of control strategies for eight EESSs with a total capacity of 101 MW/202 MWh in the automatic generation control (AGC) in the power system of the Jiangsu power grid. Firstly, an adaptive tracking strategy for electricity quantity that considers the state of charge (SOC) of EESSs is proposed to calculate the baseline power of the EESS participating in AGC. This strategy can simultaneously coordinate different time scale application requirements, such as peak shaving and LFC. Then, an adaptive strategy for regulation requirement allocation among AGC control groups with EESSs that considers different area regulation requirements (ARRs) is proposed to calculate the regulation power of EESS participating in AGC. This strategy can realize the balance transfer of fast and slow regulation capacity, ensure the complementary advantages of various frequency regulation resources and improve the dynamic regulation performance of the control area. Finally, the proposed strategy is validated via a test system to confirm its effectiveness and advantages, as well as via a quantitative analysis on the improvement of the control performance standard (CPS) of the Jiangsu power grid with the participation of EESSs in AGC.
Sustainable Development—A Path to a Better Future
Authors: Stoenoiu Carmen Elena
Published: July 2022

The need for sustainable development is a common concern for many countries, and the level reached by each country validates the efforts made and the effects of their associated well-being. In this study, an analysis of the indicators included in SDG-9 was performed, indicators that aim to achieve sustainable industrialization, increase research and innovation, and create a resilient infrastructure. The analysis used nine indicators that measure the situation of eight Eastern European countries during 2013–2019 to signal improvements or deteriorations in situations. The study used three working hypotheses that were verified and presented the evolution of countries in the aforementioned years. The results obtained led to the ranking of the countries by evaluating their economies from the perspective of the effects obtained by the method of sustainable development, thus categorizing the countries into ones with real, moderate, and low progress.
Swamp Wetlands in Degraded Permafrost Areas Release Large Amounts of Methane and May Promote Wildfires through Friction Electrification
Authors: Xu Zhichao , Shan Wei , Guo Ying , Zhang Chengcheng , Qiu Lisha
Published: July 2022

Affected by global warming, permafrost degradation releases a large amount of methane gas, and this part of flammable methane may increase the frequency of wildfires. To study the influence mechanism of methane emission on wildfires in degraded permafrost regions, we selected the northwest section of Xiaoxing’an Mountains in China as the study area, and combined with remote sensing data, we conducted long-term monitoring of atmospheric electric field, temperature, methane concentration, and other observation parameters, and further carried out indoor gas–solid friction tests. The study shows that methane gas (the concentration of methane at the centralized leakage point is higher than 10,000 ppm) in the permafrost degradation area will release rapidly in spring, and friction with soil, surface plant residues, and water vapor will accelerate atmospheric convection and generate electrostatic and atmospheric electrodischarge phenomena on the surface. The electrostatic and atmospheric electrodischarge accumulated on the surface will further ignite the combustibles near the surface, such as methane gas and plant residues. Therefore, the gradual release of methane gas into the air promotes the feedback mechanism of lightning–wildfire–vegetation, and increases the risk of wildfire in degraded permafrost areas through frictional electrification (i.e., electrostatic and atmospheric electrodischarge).
Perspectives of Hybrid Performing Arts Education in the Post-Pandemic Era: An Empirical Study in Hong Kong
Authors: Li Zihao (Michael) , Li Qingyun , Han Jie , Zhang Zhongyang
Published: July 2022

While the COVID-19 pandemic has been raging across the continents, performing arts educators have unlearned and adjusted their pedagogies in course delivery to surmount the challenges caused by the COVID-19 pandemic. Subject to the COVID-19 pandemic situation easing in Hong Kong and around the world, the whole education sector seems to be bouncing back to normal gradually. Meanwhile, there are effective lessons and insights to be learned from the hybrid pedagogy during the pandemic, which could further benefit the new normal period (post-pandemic) of performing arts education. To examine the current practice of digital learning among students and faculty (attitudes towards hybrid, online, and face-to-face learning and preferences about learning mode for professional development/training workshops), this empirical study looks at 408 students and 17 faculty members at a leading performing arts institute in Hong Kong. This study locates the key issues for performing arts educators regarding online/hybrid teaching and learning. It presents lessons and insights for quality insurance and improvement. Findings can inform the future development of digital teaching and learning for the performing arts as well as for other practice-based subjects.
Intangibles, Firm Performance, and CEO Characteristics: Spotlight on the EU Electricity and Gas Industry
Authors: Curea Mihaela , Mironiuc Marilena , Huian Maria Carmen
Published: July 2022

The transition from the industrial economy to the knowledge-based economy has changed the status quo, and consequently, intangibles have gained traction in the scientific discourse of recent decades. The paper aims to scrutinise, econometrically, the nexus between intangibles and firm performance and the moderating role of CEO duality and CEO gender. Capital-intensive industries are largely overlooked by previous studies, which prompted us to explore the electricity and gas industry. The analysis is based on a longitudinal dataset of EU-listed companies and employs a quantitative approach to study the causal relationships between intangibles, firm performance, and CEO characteristics. Results demonstrate that intangible assets are a stepping stone to better financial and market performance, which endorses the resource-based view. Today’s social and cultural milieu sees gender diversity in a positive light. Consonant with the upper echelons theory, the study finds that CEO gender positively impacts the intangibles–firm performance relationship. The hypothesised prejudicial effect of CEO duality, postulated by the agency theory, is only partially supported. Managers and policymakers are advised to pay particular attention to intangibles and science-driven projects to augment corporate performance. Creating a diversity-friendly culture is also of paramount importance.
Heavy Metals in Honey Collected from Contaminated Locations: A Case of Lithuania
Authors: Šerevičienė Vaida , Zigmontienė Aušra , Paliulis Dainius
Published: July 2022

Honey, as a bioindicator, can be used to determine the level of pollution in the environment with selected pollutants, including heavy metals. Twelve locations were selected for experimental studies near the main sources of pollution: industrial sites, landfills, railways, and highways. The honey samples were burned to ash, and the heavy metals in ashes were determined using aqua regia digestion in the microwave digestion system. The concentration of heavy metals (Cd, Cr, Cu, Pb, and Ni) was determined using a Buck Scientific model 210 VGP atomic absorption spectrophotometer with a graphite furnace atomizer and an acetylene-air flame. These median amounts of heavy metals were found in the analyzed honey samples: 0.0030 mg/kg for Cd, 0.0179 mg/kg for Pb, 0.0317 mg/kg for Cr, 0.0999 mg/kg for Cu, and 0.0332 mg/kg for Ni. The obtained results were compared with honey samples research conducted in other countries. It is difficult to compare the level of heavy metal results found in honey from different countries, as the type of honey, soil composition, rainfall, air temperature, the plants from which it was harvested, its vegetation and flowering duration, and the degree of anthropogenic pollution in the area differ. The heavy metal content tested in honey was found to be low, except for the Pb content in one sample of honey, and did not pose a risk to human health. A statistical analysis including average, median, standard deviation, confidence intervals, and Spearman coefficients was performed for the evaluation of the relationships between the heavy metal quantities and the determination of the impact of pollution sources (transport and industry). The correlation analysis showed a strong negative correlation coefficient between heavy metals and distance (r = −0.593 to −0.204).
The Impact Factors of Industry 4.0 on ESG in the Energy Sector
Authors: Nitlarp Theerasak , Kiattisin Supaporn
Published: July 2022

Digital transformation refers to highly thought-out social, manufacturing, and organizational transitions driven by digital revolutions and emerging technologies. On the other hand, energy is a critical pillar of the economic growth of the country. Meanwhile, global interest in environmental, social, and governance (ESG) investment is growing. The conventional investment paradigm is being phased out in favor of investments that prioritize environmental, social, and corporate responsibility. The energy sector is one of the most significantly affected. Presently, the field of digital transformation is limited in its analysis about the sustainability factors and is still controversial, especially in the energy business. This paper identifies an in-corporation factor in Industry 4.0, taking into account the effect on ESG. The research papers and the World Economic Forum reports were investigated and identified the correlation factor using machine learning to analyze their contents. We spotlighted the documents relevant to the energy industry and sustainable development. To quantify the model, confirmatory factor analysis (CFA) is proposed to generate a valid model, followed by path analysis with latent variables to evaluate the structural equation modeling (SEM). The result provides the conceptual model with impact factors and their correlations. The goodness of fit value is acceptable for the agreed-upon condition, as well as a descriptive that incorporates Industry 4.0 and ESG in terms of business, industry, and ESG in relation to the energy sector’s key issues.
Analysis and Evaluation of Variation Characteristics in Groundwater Resources Carrying Capacity in Beijing between 2010 and 2020
Authors: Ge Yinxin , Wu Jin , Li Binghua , Cao Xiaoyuan , Wu Jiangyue
Published: July 2022

The problems of water shortages and groundwater overexploitation are serious in Beijing. Resources are over-exploited to meet the industrial needs of various sectors, and the capacity of groundwater resources to support economic development is also reduced. Therefore, it is of great significance to study the evaluation of regional groundwater resources carrying capacity from the perspective of time and space. This study evaluates the groundwater resource carrying capacity of Beijing from time and space by using the function between water use efficiency and groundwater availability constructed by regional water supply, consumption data and GDP data. The results show that: The proportion of groundwater in water supply in Beijing has decreased and it was still one of the main sources of water supply from 2010 to 2020. From the perspective of time, when the degree of groundwater exploitation (De) was greater than 1, the contribution rate of exploitation degree of economic development (Dg) reached 60% from 2010 to 2015, indicating that the economic development of Beijing is highly dependent on groundwater resources. From 2015 to 2020, the De was less than 1, but the Dg value kept increasing and approaching 90% and the total overload rate was 81.8%. The supporting capacity of groundwater resources will become more fragile. At the spatial scale, only the Dongcheng and the Xicheng regions were overloaded whose rates were 58.48% and 69.92%. The research shows that the degree of groundwater exploitation has approached the saturation state, the economic development is highly dependent on groundwater resources and there is a large space for water saving. Improving the utilization efficiency of water resources cannot improve the carrying capacity of groundwater resources, so it is still necessary to increase the amount of groundwater resources by recharging the groundwater through a series of comprehensive over-exploitation control measures, which is of great significance to the management and sustainable development of regional groundwater.
Effect of Structural Parameters and Operational Characteristic Analysis on Ejector Used in Proton Exchange Membrane Fuel Cell
Authors: Li Chao , Sun Baigang , Luo Qinghe
Published: July 2022

A hydrogen ejector for PEMFC system is designed based on thermodynamic theory with considering the influence of water vapor. A CFD model is built in order to optimize the geometric parameters, comprehensively considering performance of different operating conditions. Moreover, effect of structural parameters and operating conditions on PEMFC ejector performance was studied using single-factor and multi-factor analysis methods. The single-factors analysis results show that the nozzle throat diameter, nozzle divergent angle (A), nozzle throat length (B), nozzle exit position (C), mixing tube diameter (D), mixing tube length (E) and are crucial structural parameters that affect the performance of the ejector significantly. Multi-factors analysis is carried to gain the sensitivity of the crucial parameters and further optimize performance of the ejector on PEMFC. For low current (110 A), middle current (275 A), and high current (412.5 A), the order of influence of performance were (D > A > B > C > E), (D > A > B> E > C), and (D > C > E > B > A), respectively. The optimized ejector by multi-factor analysis method has a better performance than one optimized by single-factor. This study may provide a new way of thinking for optimization of structural parameters of any PEMFC ejector with various operating condition.
Digital Economy, Financial Development, and Energy Poverty Based on Mediating Effects and a Spatial Autocorrelation Model
Authors: Qu Junhong , Hao Xiaoli
Published: July 2022

How to effectively solve the problem of energy poverty from the perspective of digital economy is a topic worthy of attention. As a new economic form characterized by information technology, does the digital economy have an important impact on energy poverty? What is the inner mechanism? Based on the theoretical analysis of the internal mechanism of the impact of the digital economy on energy poverty, this paper systematically investigates the impact of the digital economy on energy poverty by establishing a mediation effect model, spatial autocorrelation test, and heterogeneity analysis, taking 30 provinces in China as the research object. The study found that: (1) the digital economy has a significant mitigation effect on energy poverty, there are regional differences, and the mitigation effect is more obvious under a high level of digital economic development; (2) financial development is one of the mechanisms involved in alleviating energy poverty, and only the intermediary effect in the eastern region is significant; (3) energy poverty has a gradually increasing positive spatial correlation and obvious spatial agglomeration characteristics. Finally, this research provides policy implications for fully realizing the potential of the role of the digital economy and financial development, thereby alleviating energy poverty.
Public Acceptability of Environmentally Linked Congestion and Parking Charging Policies in Greek Urban Centers
Authors: Petraki Virginia , Papantoniou Panagiotis , Korentzelou Asimina , Yannis George
Published: July 2022

Nowadays, urban centers face the challenge to upgrade life quality by reducing traffic congestion, air pollution emissions and road casualties. Transport charging policies applied in cities at a quick pace are a key tool for sustainable mobility. However, public acceptability is an important precondition to be adopted for such policies. In this context, the scope of this paper is the investigation of the public acceptability of environmentally linked urban charging policies in Greek urban centers. Specifically, the paper’s objective is the investigation of Greek drivers’ acceptability of the implementation of a congestion charging policy and a parking charging policy with the charging being adjusted according to the Euro class and technology of the vehicle in favor of less polluting cars. A structural equation model (SEM) was developed using data from a questionnaire survey which provided a sample encompassing 733 respondent drivers from three main urban centers of Greece: Athens, Thessaloniki and Volos. Several statistical relationships were detected and quantified correlating the two examined urban environmental charging policies with five latent unobserved variables. Based on the results, public acceptability of environmental congestion charging policies and the public acceptability of environmental parking charging policies were found to be positively correlated with each other, meaning that a driver who supports one environmentally linked transport charging policy is more likely to support the other one as well. The environmental sensitivity and high commuting profiles of drivers are influential factors that positively affect the acceptability of the two examined transport charging policies’ implementation in Greek urban centers. Analysis has also shown that younger, higher-educated respondents and females are more likely to accept the environmental charging policies under consideration.
Interaction between Urbanization and Eco-Environment in Hebei Province, China
Authors: Wang Hefeng , Zhao Ao , Cao Yuan , Xie Yi , Guo Lanxuan
Published: July 2022

Understanding the complex interaction between urbanization and the eco-environment is necessary for rapid and quality urbanization, eco-environmental protection, and the harmonious coexistence of humans and nature within a region. Based on panel data from Hebei Province between 1985 and 2019, we suggested a symbiosis hypothesis of urbanization and the eco-environment (SHUE) and used the distance coordination coupling model, the Tapio decoupling model, and the symbiosis model to quantitatively determine the interaction relationship between urbanization and the eco-environment. We found that (1) the improved ‘Northam curve’ of urbanization in Hebei Province met the logistic equation. (2) During the study period, the coordinated coupling degree (CCD) of urbanization and eco-environment exhibited an overall upward trend, while the coupling type gradually changed from the endangered imbalance recession type to the coordinated development type. (3) The decoupling types showed strong and weak decoupling fluctuations, with a high frequency of strong decoupling; the growth rate of the urbanization index was higher than that of the eco-environment index; and there was a positive effect between urbanization and eco-environment indicating positive urbanization. (4) The research results verified SHUE. The symbiosis mode of urbanization and eco-environment was mainly asymmetric mutualism, with the two demonstrating mutual promotion and mutualism. However, in 2016–2019, the symbiosis mode became parasitic, urbanization development enforced upon the eco-environment. The study constructed a set of quantitative method to systematically discuss the interaction relationship from two dimensions: coupling and decoupling. The results provide reference for the coordinated development of urbanization and eco-environment in Hebei Province and consequentially enrich this research field.
Optimal Method for Biomass Estimation in a Cladoceran Species, Daphnia Magna (Straus, 1820): Evaluating Length–Weight Regression Equations and Deriving Estimation Equations Using Body Length, Width and Lateral Area
Authors: Ku Doyeong , Chae Yeon-Ji , Choi Yerim , Ji Chang Woo , Park Young-Seuk , Kwak Ihn-Sil , Kim Yong-Jae , Chang Kwang-Hyeon , Oh Hye-Ji
Published: July 2022

Assessing the biomass of zooplankton compensates for the difference between number of individuals and the accumulated body weight of the community, which helps assess aquatic ecosystem food web functions. Daphnia are crustaceans that play an intermediate role in biological interactions within food webs. The morphology and body specification of Daphnia differ during growth; hence, it is essential to apply species-specific equations to estimate biomass. We evaluated the length–weight regression equations used previously to estimate Daphnia magna biomass and conducted regression analyses using various body specifications and biomass measurements taken directly using devices such as a microbalance and microscopic camera. Biomass estimated using an equation from the Environmental Protection Agency was significantly different from the direct measurement: average biomass was lower, indicating that the equation possibly underestimated actual biomass. The biomass of D. magna had a higher multiple R2 value when length was compared with width and area, and a linear regression equation was the most suitable equation for biomass estimation. Because body specifications and biomass are affected by various environmental factors, the development of accurate species-specific biomass estimation equations will contribute to obtaining fundamental data with which the biological responses of zooplankton to aquatic ecosystem changes can be assessed.
Study on Construction and Reinforcement Technology of Dolomite Sanding Tunnel
Authors: Wang Meiqian , Xu Wei , Mu Hongyuan , Mi Jian , Wu Yonghong , Wang Yangxing
Published: July 2022

The No. 2 conduit of the Xiaopu Tunnel in the Yuxi section of central Yunnan’s water diversion project is taken as the research object, starting from the geological conditions along with the characteristics, formation mechanism and evolutionary model of dolomite sanding. This paper discusses the engineering problems of the project’s tunnels with dolomite sanding in the water-rich section, and its corresponding engineering reinforcement plan. It was found that in the tunnel section with normal level of dolomite sanding, there was no water seepage, where measures such as advanced small conduit, mechanical excavation, short grubbing and strong support could all be adopted for safe passage. Even in the water seepage section of the weak dolomite sanding tunnel, the surrounding rock was found in close interlock with strong self-stability. The excavation and support were implemented according to the category of normal surrounding rock. In the water-rich sections with strong and intense dolomite sanding, gushing of water and sand were quite frequent, with developed fissures, broken rock masses and rich waters. During the engineering operation, phosphoric acid and sodium silicate slurry in addition to urea formaldehyde resin and oxalic acid slurry plus Malisan and liquid catalyst slurry were first prepared for water plugging. Then, pure water slurry was used for surrounding rock reinforcement, which exerted an excellent effect. This method can provide reference for reinforcing tunnels of sandy dolomite in other areas of projects.
A Review of Current and Historical Research Contributions to the Development of Ground Autonomous Vehicles for Agriculture
Authors: Rondelli Valda , Franceschetti Bruno , Mengoli Dario
Published: July 2022

In this study, a comprehensive overview of the available autonomous ground platforms developed by universities and research groups that were specifically designed to handle agricultural tasks was performed. As cost reduction and safety improvements are two of the most critical aspects for farmers, the development of autonomous vehicles can be of major interest, especially for those applications that are lacking in terms of mechanization improvements. This review aimed to provide a literature evaluation of present and historical research contributions toward designing and prototyping agricultural ground unmanned vehicles. The review was motivated by the intent to disseminate to the scientific community the main features of the autonomous tractor named BOPS-1960, which was conceived in the 1960s at the Alma Mater Studiorum University of Bologna (UNIBO). Jointly, the main characteristics of the modern DEDALO unmanned ground vehicle (UGV) for orchard and vineyard operations that was designed recently were evaluated. The basic principles, technology and sensors used in the two UNIBO prototypes are described in detail, together with an analysis of UGVs for agriculture conceived in recent years by research centers all around the world.
A Core-Shell Amino-Functionalized Magnetic Molecularly Imprinted Polymer Based on Glycidyl Methacrylate for Dispersive Solid-Phase Microextraction of Aniline
Authors: Tadić Tamara , Marković Bojana , Radulović Jelena , Lukić Jelena , Suručić Ljiljana , Nastasović Aleksandra , Onjia Antonije
Published: July 2022

A core-shell amino-functionalized glycidyl methacrylate magnetic molecularly imprinted polymer (MIP) was synthesized by the suspension polymerization/surface imprinting method and characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), mercury porosimetry, nitrogen gas adsorption–desorption, and elemental analysis. This MIP was used as the sorbent in dispersive solid-phase microextraction (DSPME) of aniline from textile wastewater prior to high-performance liquid chromatography-mass spectrometry (HPLC-MS) measurements. Since aniline is toxic and a probable human carcinogen, its determination in water is of great significance. This is a challenging task because aniline is usually present at trace levels. The effects of different DSPME variables on the preconcentration efficiency have been studied by using the Plackett–Burman screening design of experiments (DoE) followed by response surface methodology optimization using the Box-Behnken design. Thus, DoE enabled the investigation of several variables simultaneously. Under optimized conditions, aniline was effectively and selectively separated by a small amount of the DSPME sorbent and detected in real textile wastewater samples. The method detection limit of 1 ng mL−1 was attained, with good method linearity and acceptable recovery and precision. The results showed that the studied MIP could be a reliable DSPME sorbent for efficiently analyzing trace aniline in real wastewater samples.
Proposal of Risk Identification Methodology Using the Prompt List on the Example of an Air Carrier
Authors: Blišťanová Monika , Tirpáková Michaela , Galanda Jozef
Published: July 2022

Risk management and safety are often-mentioned topics that dominate, especially in this period. The Safety Management System (SMS) is based on risk management, the implementation of which is required in air transport as well as in other modes of transportation. The fact is that the safety of passengers and staff is a priority for every airline, and such individuals are exposed to some common groups of risks. Risk identification is vital in successful risk management as only identified risks can be managed. Based on a study of published frameworks and standards, a risk identification methodology was designed using a prompt list of a logically arranged list of risks concerning typical aviation activities and the specific environment in which the methodology operates. The prompt list was compiled based on a context analysis, which focused on internal and external contexts and on which the structure of the prompt list was based so that risks could be moved from the list to a risk register for further processing based on various criteria. The list contains risks from several areas (economic, ecologic, social, individual, business, marketing, etc.). The design of the prompt list itself also includes a proposal for a methodology for its compilation, use, and updating.