bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of Temperature Effects into Long-Span Bridges via Hybrid Sensing and Supervised Regression Models
Authors: Behkamal Bahareh , Entezami Alireza , De Michele Carlo , Arslan Ali Nadir
Published: July 2023

Temperature is an important environmental factor for long-span bridges because it induces thermal loads on structural components that cause considerable displacements, stresses, and structural damage. Hence, it is critical to acquire up-to-date information on the status, sustainability, and serviceability of long-span bridges under daily and seasonal temperature fluctuations. This paper intends to investigate the effects of temperature variability on structural displacements obtained from remote sensing and represent their relationship using supervised regression models. In contrast to other studies in this field, one of the contributions of this paper is to leverage hybrid sensing as a combination of contact and non-contact sensors for measuring temperature data and structural responses. Apart from temperature, other unmeasured environmental and operational conditions may affect structural displacements of long-span bridges separately or simultaneously. For this issue, this paper incorporates a correlation analysis between the measured predictor (temperature) and response (displacement) data using a linear correlation measure, the Pearson correlation coefficient, as well as nonlinear correlation measures, namely the Spearman and Kendall correlation coefficients and the maximal information criterion, to determine whether the measured environmental factor is dominant or other unmeasured conditions affect structural responses. Finally, three supervised regression techniques based on a linear regression model, Gaussian process regression, and support vector regression are considered to model the relationship between temperature and structural displacements and to conduct the prediction process. Temperature and limited displacement data related to three long-span bridges are used to demonstrate the results of this research. The aim of this research is to assess and realize whether contact-based sensors installed in a bridge structure for measuring environmental and/or operational factors are sufficient or if it is necessary to consider further sensors and investigations.
Two Decades of Terrestrial Water Storage Changes in the Tibetan Plateau and Its Surroundings Revealed through GRACE/GRACE-FO
Authors: Xiang Longwei , Wang Hansheng , Steffen Holger , Jiang Liming , Shen Qiang , Jia Lulu , Su Zhenfeng , Wang Wenliang , Deng Fan , Qiao Baojin , Cui Haifu , Gao Peng
Published: July 2023

The Tibetan Plateau (TP) has the largest number of high-altitude glaciers on Earth. As a source of major rivers in Asia, this region provides fresh water to more than one billion people. Any terrestrial water storage (TWS) changes there have major societal effects in large parts of the continent. Due to the recent acceleration in global warming, part of the water environment in TP has become drastically unbalanced, with an increased risk of water disasters. We quantified secular and monthly glacier-mass-balance and TWS changes in water basins from April 2002 to December 2021 through the Gravity Recovery and Climate Experiment and its Follow-on satellite mission (GRACE/GRACE-FO). Adequate data postprocessing with destriping filters and gap filling and two regularization methods implemented in the spectral and space domain were applied. The largest glacier-mass losses were found in the Nyainqentanglha Mountains and Eastern Himalayas, with rates of −4.92 ± 1.38 Gt a−1 and −4.34 ± 1.48 Gt a−1, respectively. The Tien Shan region showed strong losses in its eastern and central parts. Furthermore, we found small glacier-mass increases in the Karakoram and West Kunlun. Most of the glacier mass change can be explained by snowfall changes and, in some areas, by summer rainfall created by the Indian monsoon. Major water basins in the north and south of the TP exhibited partly significant negative TWS changes. In turn, the endorheic region and the Qaidam basin in the TP, as well as the near Three Rivers source region, showed distinctly positive TWS signals related to net precipitation increase. However, the Salween River source region and the Yarlung Zangbo River basin showed decreasing trends. We suggest that our new and improved TWS-change results can be used for the maintenance of water resources and the prevention of water disasters not only in the TP, but also in surrounding Asian countries. They may also help in global change studies.
An Hybrid Integration Method-Based Track-before-Detect for High-Speed and High-Maneuvering Targets in Ubiquitous Radar
Authors: Peng Xiangyu , Song Qiang , Zhang Yue , Wang Wei
Published: July 2023

Due to the limited transmission gain of ubiquitous radar systems, it has become necessary to use a long-time coherent integration method for range-Doppler (RD) analysis. However, when the target exhibits high-speed and high-maneuver capabilities, it introduces challenges, such as range migration (RM), Doppler frequency migration (DFM), and velocity ambiguity (VA) in the RD domain, thus posing significant difficulties in target detection and tracking. Moreover, the presence of VA further complicates the problem. To address these complexities while maintaining integration efficiency, this study proposes a hybrid integration approach. First, methods called Keystone-transform (KT) and matched filtering processing (MFP) are proposed for compensating for range migration (RM) and velocity ambiguity (VA) in Radar Detection (RD) images. The KT approach is employed to compensate for RM, followed by the generation of matched filters with varying ambiguity numbers. Subsequently, MFP enables the production of multiple RD images covering different but contiguous Doppler frequency ranges. These RD images can be compiled into an extended RD (ERD) image that exhibits an expanded Doppler frequency range. Second, an improved particle-filter (IPF) algorithm is raised to perform incoherent integration among ERD images and to achieve track-before-detect (TBD) for a target. In the IPF, the target state vector is augmented with ambiguous numbers, which are estimated via maximum posterior probability estimation. Then, to compensate for the DFM, a line spread model (LSM) is proposed instead of the point spread model (PSM) used in traditional PF. To evaluate the efficacy of the proposed method, a radar simulator is devised, encompassing comprehensive radar signal processing. The findings demonstrate that the proposed approach achieves a harmonious equilibrium between integration efficiency and computational complexity when it comes to detecting and tracking high-speed and high-maneuvering targets with intricate maneuvers. Furthermore, the algorithm’s effectiveness is authenticated by exploiting ubiquitous radar data.
Small Field Plots Can Cause Substantial Uncertainty in Gridded Aboveground Biomass Products from Airborne Lidar Data
Authors: Cushman K. C. , Saatchi Sassan , McRoberts Ronald E. , Anderson-Teixeira Kristina J. , Bourg Norman A. , Chapman Bruce , McMahon Sean M. , Mulverhill Christopher
Published: July 2023

Emerging satellite radar and lidar platforms are being developed to produce gridded aboveground biomass (AGB) predictions that are poised to expand our understanding of global carbon stocks and changes. However, the spatial resolution of AGB map products from these platforms is often larger than the available field plot data underpinning model calibration and validation efforts. Intermediate-resolution/extent remotely sensed data, like airborne lidar, can serve as a bridge between small plots and map resolution, but methods are needed to estimate and propagate uncertainties with multiple layers of data. Here, we introduce a workflow to estimate the pixel-level mean and variance in AGB maps by propagating uncertainty from a lidar-based model using small plots, taking into account prediction uncertainty, residual uncertainty, and residual spatial autocorrelation. We apply this workflow to estimate AGB uncertainty at a 100 m map resolution (1 ha pixels) using 0.04 ha field plots from 11 sites across four ecoregions. We compare uncertainty estimates using site-specific models, ecoregion-specific models, and a general model using all sites. The estimated AGB uncertainty for 1 ha pixels increased with mean AGB, reaching 7.8–33.3 Mg ha−1 for site-specific models (one standard deviation), 11.1–28.2 Mg ha−1 for ecoregion-specific models, and 21.1–22.1 Mg ha−1 for the general model for pixels in the AGB range of 80–100 Mg ha−1. Only 3 of 11 site-specific models had a total uncertainty of <15 Mg ha−1 in this biomass range, suitable for the calibration or validation of AGB map products. Using two additional sites with larger field plots, we show that lidar-based models calibrated with larger field plots can substantially reduce 1 ha pixel AGB uncertainty for the same range from 18.2 Mg ha−1 using 0.04 ha plots to 10.9 Mg ha−1 using 0.25 ha plots and 10.1 Mg ha−1 using 1 ha plots. We conclude that the estimated AGB uncertainty from models estimated from small field plots may be unacceptably large, and we recommend coordinated efforts to measure larger field plots as reference data for the calibration or validation of satellite-based map products at landscape scales (≥0.25 ha).
Bringing to Light the Potential of Angular Nighttime Composites for Monitoring Human Activities in the Brazilian Legal Amazon
Authors: Bragion Gabriel da Rocha , Dal’Asta Ana Paula , Amaral Silvana
Published: July 2023

The Brazilian Legal Amazon (BLA) is the largest administrative unit in Brazil. The region has undergone a series of territorial policies that have led to specific conditions of occupation of the land and particular urban environments. This plurality expresses specific physical relations with the environment and infrastructure, which require innovative methods for detecting and profiling human settlements in this region. The aim of this work is to demonstrate how angular composites of nighttime lights can be associated with specific profiles of urban infrastructure, sociodemographic parameters, and mining sites present in the BLA. We make use of sets of yearly VNP46A4 angular composites specifically associated with the narrowest ranges of observations across the year, i.e., observations right below the sensor’s pathway (near-nadir range) and observations in between the oblique range (off-nadir), to identify urban typologies that expose the presence of structures such as vertical buildings, industrial sites, and areas with different income levels. Through a non-parametric evaluation of the simple difference in radiance values ranging from 2012 to 2021, followed by an ordinary least squares regression (OLS), we find that off-nadir values are persistently higher than near-nadir values except in areas where obstructing structures and particular anisotropic characteristics are present, generally changing trends of the so-called angular effect. We advocate that relational metrics can be extracted from the angular annual composites to provide additional information on the current urban structural state. By calculating the simple difference (DIF), the relative difference (REL), and the residual values of the linear regression formula estimated for the off-nadir and near-nadir composites (RES), it is possible to differentiate urban environments by their physical aspects, such as high-mid income areas, low-income settlements with different levels of density, industrial sites, and verticalized areas. Moreover, pixels that were exclusively found in one of the angular composites could be spatially associated with phenomena such as the overglow effect for the exclusive off-nadir samples and with the wetlands of the northwest portion of the Amazon Forest for the near-nadir samples. This work deepens our current understanding of how to optimize the use of the VNP46A4 angular series for monitoring human activities in the Amazon biome and provides further directions on research possibilities concerning nighttime light angular composites.
A New Spatio-Temporal Selection Method for Estimating Upwelling Medium-Wave Radiation
Authors: Hally Bryan , Wallace Luke , Reinke Karin , Jones Simon
Published: July 2023

Accurate estimates of the unperturbed state of upwelling radiation from the earth’s surface are vital to the detection and classification of anomalous radiation values. Determining radiative anomalies in the landscape is critical for isolating change, a key application being wildfire detection, which is reliant upon knowledge of a location’s radiation budget sans fire. Most techniques for deriving the unperturbed background state of a location use that location’s spatial context, that is, the pixels immediately surrounding the target. Spatial contextual estimation can be subject to error due to occlusion of the pixel’s spatial context and issues such as land cover heterogeneity. This paper proposes a new method of deriving background radiation levels by decoupling the set of prediction pixels used for estimation from the target location in a Spatio-Temporal Selection (STS) process. The process selects training pixels for predictive purposes from a target-centred search area based on their similarity with the target pixel in terms of brightness temperature over a prescribed time period. The proposed STS process was applied to images from the AHI-8 geostationary sensor centred over the Asia-Pacific, and comparisons were made to both brightness temperature estimates from the spatial context and to sensor measurements. This comparison showed that the STS method provided between 10–40% reduction in estimation error over the commonly utilised contextual estimator; in addition, the STS method increased the availability of estimates in comparison to the spatial context by between 12–31%. Image reconstruction using the method resulted in high-fidelity reproductions of the examined landscape, with standing geographic features and areas experiencing thermal anomalies readily identifiable on the resulting images.
Directional and High-Gain Ultra-Wideband Bow-Tie Antenna for Ground-Penetrating Radar Applications
Authors: Pi Shuai , Wang Tianhao , Lin Jun
Published: July 2023

Bow-tie antennas are utilized extensively in ground-penetrating radar (GPR) systems. In order to achieve sufficient penetration depth and resolution, the bow-tie antennas for GPR applications require low operating frequency, high gain, and excellent broadband. A novel ultra-wideband (UWB) bow-tie antenna with gain enhancement for GPR applications is proposed in this paper. First, a UWB bow-tie antenna with resistive loading is designed. The metal reflector and metamaterial loading make the bow-tie antenna directional, and loading the same metamaterial on the front side of the antenna further improves directional gain. After testing, the lowest frequency of the fabricated antenna is 317 MHz, the relative bandwidth is 98.6%, the peak gain in the frequency range is 9.3 dBi, and the size is only 0.38 λ at the lowest frequency. The proposed compact antenna takes both gain and bandwidth into consideration. Finally, in order to further verify the effectiveness of the proposed antenna in the GPR system, a stepped frequency continuous wave ground-penetrating radar (SFCW-GPR) system was built. The experimental results show that the designed antenna is suitable for the GPR system of deep penetration and high-resolution detection, which is beneficial to the imaging of underground structures.
Landsat 9 Geometric Commissioning Calibration Updates and System Performance Assessment
Authors: Choate Michael J. , Rengarajan Rajagopalan , Storey James C. , Lubke Mark
Published: July 2023

Starting with launch of Landsat 7 (L7) on 15 April 1999, the USGS Landsat Image Assessment System (IAS) has been performing calibration and characterization operations for over 20 years on the Landsat spacecrafts and their associated payloads. With the launch of Landsat 9 (L9) on 27 September 2021, that spacecraft and its payloads, the Operational Land Imager-2 (OLI-2) and Thermal Infrared Sensor-2 (TIRS-2), were added to the existing suite of missions supported by the IAS. This paper discusses the geometric characterizations, calibrations, and performance analyses conducted during the commissioning period of the L9 spacecraft and its instruments. During this time frame the following calibration refinements were performed; (1) alignment between the OLI-2 and TIRS-2 instruments and the spacecraft attitude control system, (2) within-instrument band alignment, (3) instrument-to-instrument alignment. These refinements, carried out during commissioning and discussed in this paper, were performed to provide an on-orbit update to the pre-launch calibration parameters that were determined through Ground System Element (GSE) testing and Thermal Vacuum Testing (TVAC) for the two instruments and the L9 spacecraft. The commissioning period calibration update captures the effects of launch shift and zero-G release, and typically represents the largest changes that are made to the on-orbit geometric calibration parameters during the mission. The geometric calibration parameter updates performed during commissioning were done prior to releasing any L9 products to the user community. This commissioning period also represents the time frame during which focus is more strictly placed on the spacecraft and instrument performance, ensuring that system and instrument requirements are met, as contrasted with the post commissioning time frame when a greater focus is placed on the products generated, their behavior and their impact on the user community. Along with the calibration updates discussed in this paper key geometric performance requirements with respect to geodetic accuracy, geometric accuracy, and swath width are presented, demonstrating that the geometric performance of the L9 spacecraft and its’ instruments with respect to these key performance requirements are being met. Within the paper it will be shown that the absolute geodetic accuracy is met for OLI-2 and TIRS-2 with a margin of approximately 79% and 65% respectively while the geometric accuracy is met for OLI-2 and TIRS-2 with a margin of approximately 68% and 43% respectively.
Implementing Smart Services in Small- and Medium-Sized Manufacturing Companies: On the Progress of Servitization in the Era of Industry 4.0
Authors: Winter Johannes
Published: July 2023

For a long time, the challenge has been to provide products and services that precisely match the preferences, habits, and needs of users [...]
The Mediating Role of Positive and Negative Affect in the Relationship between Death Anxiety and Italian Students’ Perceptions of Distance Learning Quality during the COVID-19 Pandemic
Authors: Sergi Maria Rita , Picconi Laura , Fermani Alessandra , Bongelli Ramona , Lezzi Sara , Saggino Aristide , Tommasi Marco
Published: July 2023

Recent data show that death anxiety and negative affect (NA) have become increasingly relevant because of the COVID-19 pandemic. The constant reminders of mortality through mass media and social media have contributed to this trend. Simultaneously, students have experienced a sudden and radical shift from face-to-face to online teaching, reducing direct human interactions and increasing anxiety. Death anxiety is often associated with mental illnesses and maladaptive mood states such as depression, anxiety, and NA. Despite this, few studies have investigated the effect of death anxiety, positive affect (PA), and NA on students’ perceived quality of distance learning. The present study aims to investigate the association among death anxiety, PA, NA, and the perceived quality of distance learning in a sample of 429 students attending university or training courses. Positive and negative affect were assessed through the positive and negative affect scales; death anxiety was measured through the death anxiety scale, and the perceived quality of distance learning was evaluated through the perceived quality of distance learning questionnaire. Zero-order correlation coefficients were calculated among the examined variables. To study the mediating role of positive and negative affect in the relationship between students’ perceptions of distance learning quality and death anxiety, we employed multiple regression analyses. Our findings indicate a significant association between death anxiety and cognitive–emotive reactions to distance learning. Lower levels of death anxiety are associated with PA, while higher levels are related to NA. Moreover, PA and NA act as mediators in the relationship between death anxiety and a positive reaction to distance learning. In conclusion, our findings highlight that PA and NA partially mediate the relationship between death anxiety and the perceived quality of distance learning.
Gender-Linked Dynamics and Sustainable Small Holder Poultry Value Chains in Makueni County, Kenya
Authors: Bukachi Salome A. , Ngutu Mariah , Omia Dalmas , Musyoka Mercy M. , Chemuliti Judith , Nyamongo Isaac K.
Published: July 2023

Understanding the gender-linked dynamics in the small holder poultry value chain is necessary for enabling sustainable agriculture and food systems. Small holder livestock production, including poultry keeping in sub-Saharan Africa (SSA), plays important socio-economic and food security roles in rural communities. Poultry production contributes to sustainable food systems as it supports nutrient cycling through feed, manure, and soils. A qualitative study utilized data from 18 focus group discussions (FGDs) and 22 in-depth interviews (IDIs) to interrogate the gender-linked dynamics in the value chain and inform interventions for sustainable food systems. The data were audio-recorded, transcribed, and coded into themes responding to the study question. The results highlight the gender-linked drivers, namely, the social and economic value placed on poultry, ownership, power positions, and decision making dynamics in production and management among small holder poultry value chain actors in Makueni County, Kenya. The study findings demonstrate the increasing economic and social value placed on poultry in households and communities. The study further discusses gender-disaggregated ownership and decision making in the poultry value chain, highlighting the need to engage all involved actors to develop sustainable food systems. In addition to the social and economic value of poultry to small holder farmers, it is necessary to factor in potential nutrition and environmental benefits. While small holder poultry production has the potential to contribute to sustainable food systems economically, nutritionally, and environmentally, this study found that more emphasis is placed on socio-economic value dimensions. Noteworthy is that in ownership and decision making, gender dynamics inform the role and position of the different actors in a sustainable small holder poultry value chain that is socio-economically, nutritionally, and environmentally sound.
Digital Twins in the Construction Industry: A Comprehensive Review of Current Implementations, Enabling Technologies, and Future Directions
Authors: Omrany Hossein , Al-Obaidi Karam M. , Husain Amreen , Ghaffarianhoseini Amirhosein
Published: July 2023

This paper presents a comprehensive understanding of current digital twin (DT) implementations in the construction industry, along with providing an overview of technologies enabling the operation of DTs in the industry. To this end, 145 publications were identified using a systematic literature review. The results revealed eight key areas of DT implementation including (i) virtual design, (ii) project planning and management, (iii) asset management and maintenance, (iv) safety management, (v) energy efficiency and sustainability, (vi) quality control and management, (vii) supply chain management and logistics, and (viii) structural health monitoring. The findings demonstrate that DT technology has the capacity to revolutionise the construction industry across these areas, enabling optimised designs, improved collaboration, real-time monitoring, predictive maintenance, enhanced safety practices, energy performance optimisation, quality inspections, efficient supply chain management, and proactive maintenance. This study also identified several challenges that hinder the widespread implementation of DT in construction, including (i) data integration and interoperability, (ii) data accuracy and completeness, (iii) scalability and complexity, (iv) privacy and security, and (v) standards and governance. To address these challenges, this paper recommends prioritising standardised data formats, protocols, and APIs for seamless collaboration, exploring semantic data modelling and ontologies for data integration, implementing validation processes and robust data governance for accuracy and completeness, harnessing high-performance computing and advanced modelling techniques for scalability and complexity, establishing comprehensive data protection and access controls for privacy and security, and developing widely accepted standards and governance frameworks with industry-wide collaboration. By addressing these challenges, the construction industry can unlock the full potential of DT technology, thus enhancing safety, reliability, and efficiency in construction projects.
Development of Climate-Related Disclosure Indicators for Application in Indonesia: A Delphi Method Study
Authors: Saptono Prianto Budi , Mahmud Gustofan , Pratiwi Intan , Purwanto Dwi , Khozen Ismail , Aditama Muhamad Akbar , Khodijah Siti , Wayan Maria Eurelia , Asmara Rina Yuliastuty , Jie Ferry
Published: July 2023

Indonesia is currently preparing to adopt the climate-related disclosure standard. Before this new standard is implemented effectively, the Institute of Indonesia Chartered Accountants (IAI), the Indonesia Task Force on Comprehensive Corporate Reporting (CCR) leader, recognised the importance of harmonising this standard’s key disclosure indicators with Indonesian regulations and business characteristics. In this case, input from various constituencies may be required, particularly regarding the mechanism that enables entities with varying capabilities and levels of preparation to apply this new standard. Hence, the main objective of this paper is to develop weighted and applicable climate-related disclosure indicators. We use the Delphi method to achieve this objective by involving several experts representing various user groups that influence accounting standard formulation in Indonesia. The Delphi method is a decision-making tool that establishes an effective communication process, facilitating complex problem solving. This study finalised 44 climate-related disclosure indicators based on the results of two Delphi rounds. Overall, 48% (21/44) of climate-related disclosure indicators were identified to be highly applicable. Among these high-relevance indicators, there were 10% (2/21) Governance, 24% (5/21) Strategy, 42% (9/21) Risk Management, and 24% (5/21) Metrics and Targets indicators. Additionally, around 20% (9/44) of climate-related disclosure indicators received 100% approval from the experts. Along with various essential implications, we argue that these results provide useful additional information for the national standard setter for the climate-related disclosure standard that are efficient and less burdensome to entities.
Critical Perspectives on the New Situation of Global Ocean Governance
Authors: Chen Yitong , Liu Huirong
Published: July 2023

Global ocean governance is the concretization of global governance. Various interest groups interact with and coordinate ocean issues. Global ocean governance is inevitably linked to the new global governance landscape. In recent years, a series of new scenarios in global governance have emerged. These situations have further shaped the plurality of participants and the diversity of mechanisms in global ocean governance. Science and technology innovation and application are prerequisites and prime movers for the evolution of global ocean governance. Major worldwide crises, represented by global climate change and the coronavirus disease 2019 pandemic, have added great uncertainty to the future development of global ocean governance. The divergence of interests and positions between emerging countries and developed countries, as well as the reshaping of the global geopolitical landscape in recent years, has led to the stagnation or deadlock of a series of international negotiations and international cooperation platforms related to global ocean governance. With the deepening of global governance, non-state actors are not only objects of ocean governance but also bearers of legal obligations and enjoy varying degrees of legal rights, participating in agenda setting, rule construction, and monitoring implementation at different levels of ocean governance. From a critical jurisprudence perspective, in the practice of global ocean governance, the relationship between non-governmental organizations, states, and international organizations is more likely to be one of reconciliation than the “state–civil society” dichotomy of moral imagination. This new set of circumstances exposes the divisive and fragmented nature of global ocean governance. This study concludes that the new situation of global ocean governance constitutes a historic opportunity for countries to reexamine the role of the rule of law during the Anthropocene to bridge the fragmentation and gaps in mechanisms and achieve a truly integrated, holistic, and closely nested global ocean governance. The question of how to implement the rule of law requires the introduction of theoretical perspectives such as the Anthropocene, complex systems theory, and the community of a shared future for humanity to undertake a fundamental critical reflection and rethinking of global ocean governance.
Thermal Comfort, Growth Performance and Welfare of Olive Pulp Fed Broilers during Hot Season
Authors: Dedousi Anna , Kritsa Maria-Zoi , Sossidou Evangelia N.
Published: July 2023

This study evaluated the nutritional effect of dried olive pulp (OP), on broilers’ thermal comfort, growth parameters and welfare in a commercial poultry farm during the hot season. A number of 108 Cobb male broilers, 19 d olds were allocated into three dietary groups: controls (CON), OP3 and OP6, based on the level of OP added to their diet (0%, 3% and 6%). The thermal comfort of broilers was assessed using the temperature–humidity index (THI). Broilers’ body temperature (BT) was determined weekly. OP beneficially affected the growth performance of broilers undergoing very severe heat stress, as indicated by the increased body weight gain (BWG) recorded in OP groups compared to CON during the first week of the experiment and the higher body weight (BW) of OP fed chickens at 26 d of age (p < 0.05). At 26 d of age, OP6 broilers had lower BT (40.55 ± 0.06 °C) than CON (40.78 ± 0.09 °C) (p < 0.05). A positive dietary effect of OP in welfare parameters like feather cleanliness and panting behaviour of chickens fed 6% OP was also recorded. Using OP as feedstuff is a promising feeding strategy for alleviating the adverse effects of heat stress; it also offers the potential to recycle olive by-products, leading to an efficient waste-based circular economy.
A Novel Light-Emitting Diode Streetlight Driver Circuit Applied to a Direct Current-Input Voltage Source
Authors: Cheng Chun-An , Chang Chien-Hsuan , Cheng Hung-Liang , Chang En-Chih , Lin You-Ruei , Lan Long-Fu
Published: July 2023

With the global advocacy of green lighting and the urgent need for energy saving and carbon reduction, more and more street lighting applications have entered the era of being replaced by light-emitting diode (LED) lighting sources. This paper presents a new LED streetlight driving circuit applied to a direct current (DC)-input voltage source, which consists of a buck converter combined with a flyback converter to reduce the number of circuit components required and to recover the leakage energy of the transformer to improve energy conversion efficiency. In addition, this study also completed the analysis of the operational principle of the new LED streetlight driving circuit, and developed a prototype LED streetlight driver with DC-input voltage of 48V and output power of 72 W (36 V/2 A). Finally, the measurement results of the prototype circuit show that the output voltage ripple rate was less than 15%, the output current ripple rate was less than 6%, and the circuit efficiency was as high as 91%.
Assessment of the Regional Vulnerability to Natural Disasters in China Based on DEA Model
Authors: Wu Lihui , Ma Da , Li Jinling
Published: July 2023

China is a country highly vulnerable to natural disasters, resulting in significant losses in terms of human casualties, injuries, property damage, economic losses, infrastructure destruction, and so on each year. We propose a conceptual model based on the Data Envelopment Analysis model to evaluate regional vulnerability in mainland China using the annual data of Chinese official statistics from 2006 to 2021. The proposed model includes five input variables: regional total population, per capita GDP, population density, GDP per square kilometer, and regional total fixed investment in water conservancy, environment, and public facilities management. Additionally, it incorporates two output variables: affected people and direct economic loss. The results indicate that the vulnerability level generally decreases from West China through Central China to East China. Based on the new classification method proposed in this study, the regions are divided into five areas. These findings can serve as a reference for policymakers in enhancing disaster planning and improving the efficiency of natural disaster prevention.
Effect of Freeze–Thaw Cycles and Initial Water Content on the Pore Structure and Mechanical Properties of Loess in Northern Shaanxi
Authors: Pan Zhenxing , Yang Gengshe , Ye Wanjun , Liu Hui , Liang Bo , Yang Qian , Li Gang
Published: July 2023

Spalling disease caused by freeze–thaw cycles often occurs on the loess cut-slopes in northern Shaanxi. The deterioration of the pore structure and mechanical strength of loess under a freeze–thaw environment is one of the critical reasons underlying the occurrence of spalling disease in the slopes. In order to explore the effects of freeze–thaw cycles on the pore structure and the mechanical strength of loess, four initial water contents (7%, 9%, 12%, and 14%) and six freeze–thaw cycles (zero, one, three, five, 10, and 20) were considered in this study. Nuclear magnetic resonance (NMR) and triaxial compression tests were carried out to analyze and reveal the mechanisms of effect causing the deterioration of the soil strength that affects the stability of loess cut-slopes. The results showed that the porosity growth increased with the initial water content and continued to increase during the freeze–thaw process until a later stage of the freeze–thaw cycle, when it gradually stabilized. The stress–strain curves were primarily influenced by the number of freeze–thaw cycles, the initial water content of the samples, and the confining pressure. Both the cohesion and the internal friction angle exhibited a decay law that showed a significant decrease, then a slow decrease, and finally stabilization during the freeze–thaw process. Small and micropores were predominant among the pore structures of the loess, while medium pores were the second most common, and large pores were the least common. With the increase in the initial water content, the pores transformed from micropore structures to medium and large pore structures. The soil strength deterioration was primarily driven by the phase changes of the pore water, as well as the water migration during the freeze–thaw process. This study will be beneficial for identifying the characteristics and types of freeze–thaw disease in cut-slope engineering in seasonally frozen loess areas and providing a theoretical reference and design basis for achieving green and sustainable development in slope engineering, management, and maintenance.
Experimental Study on the Axial Deformation Characteristics of Compacted Lanzhou Loess under Traffic Loads
Authors: Yang Liguo , Shao Shengjun , Wang Fuquan , Wang Liqin
Published: July 2023

It is beneficial to the sustainable development of expressway engineering to reuse excavated soil as roadbed filling material. There are a large number of filling projects using loess as a filling material in Northwest China. In this paper, the loess subgrade of an expressway in Lanzhou is taken as the research object, and a series of experimental studies are conducted using a hollow cylindrical torsion shear system to simulate the formation of a “heart-shaped” stress path and the principal stress rotation (PSR) under long-term traffic loads. The effects of the vertical cyclic dynamic stress ratio, torsion shear stress ratio, initial static shear stress, and intermediate principal stress coefficient on the axial plastic deformation and rebound deformation of compacted loess in Lanzhou were studied. The results show that the vertical cyclic stress ratio (VCSR) has a significant effect on the axial deformation of compacted loess in Lanzhou. When the VCSR is less than 0.6, all the axial strain curves develop stably with the number of cycles. With an increasing VCSR, the axial plastic deformation increases obviously, and the axial rebound deformation also increases. The vertical cyclic dynamic stress of the specimen is constant. Moreover, increasing the torsional shear stress ratio (that is, increasing the amplitude of cyclic shear stress) can greatly increase the development of axial deformation, but it has no effect on the rebound deformation curve. When the initial static shear stress exists in the specimen, the larger the initial static stress ratio (SSR) is, the larger the axial plastic deformation. The axial plastic deformation increases by approximately 33% for every 0.1 increase in the SSR. The rebound deformation of different SSRs fluctuates at the initial stage of cyclic loading, but the final stable rebound deformation is basically the same as that at the initial stage of cyclic loading. The intermediate principal stress coefficient has no effect on the development of axial strain, and the effect on axial rebound deformation is negligible. Finally, the calculation model of the axial plastic strain of Lanzhou compacted loess under traffic loads is obtained. The research results can provide a reference for the durability and settlement prediction in loess engineering.
Wastewater Treatment and Reuse for Sustainable Water Resources Management: A Systematic Literature Review
Authors: Silva Jorge Alejandro
Published: July 2023

Wastewater treatment involves the extraction of pollutants, removal of coarse particles, and elimination of toxicants. Moreover, wastewater treatment kills pathogens and produces bio-methane and fresh manure for agricultural production. The connection between waste management and sustainability created the basis for this research. Wastewater treatment is part of the efforts to minimize water waste, minimize pressure on natural sources of water, and create a pathway for clean energy. A systematic literature review was selected for this study to evaluate and synthesize the available evidence in support of wastewater treatment for both economic and environmental sustainability. The articles were evaluated using the PRISMA framework to identify the most appropriate articles for inclusion. A total of 46 articles were selected based on their content validity, relevance to the research question, strength of evidence, year of publication (2000–2023), and relevance to sustainable resource management. The findings indicate that wastewater treatment enables sustainable resource management by improving the supply of clean water, and minimizing pressure on natural resources, energy recovery, and agricultural support. Wastewater treatment provides one of the most sustainable approaches to water conservation, energy production, and agricultural productivity.
Evidence-Based Green Human Resource Management: A Systematic Literature Review
Authors: Xie Huirong , Lau Teck Chai
Published: July 2023

To better understand the empirical development of green human resource management (GHRM) research and theories and to provide evidence-based suggestions, the article conducts a systematic review of evidence-based studies within the academic field of GHRM. The review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Protocol 2020 to select GHRM-focused and highly qualified articles, published in the final stage by the end of December 2022 and written in English from the Scopus and Web of Science Core Collection databases. Independent assessments of studies were performed by two researchers in the selection and analysis process, and bibliometric and statistical analyses were applied to synthesize the results from 141 articles. The results reveal the increasing interest, diversification, and tendencies of GHRM research and highlight the disequilibrium of research context and methodology, the classification and evolution of research emphasis, the mechanism for theories, the constructs, the measurements, and the framework of the literature. Based on the results, evidence-based recommendations were provided for both practitioners and researchers regarding the context and trend, access and approach, and mechanism and innovation for GHRM development. This review possesses significance as providing the original findings of detailed empirical GHRM research context, the relationships between GHRM practices dimensions and measurements, and the interrelation of theory application and framework design. Despite the discoveries having the potential to offer scholars and practitioners GHRM suggestions with a reliable basis, the authors recognize the scope of the current review is limited and call for verification of current findings with a wider range of studies.
Examination of Higher Education Teachers’ Self-Perception of Digital Competence, Self-Efficacy, and Facilitating Conditions: An Empirical Study in the Context of China
Authors: Wang Zhaorui , Chu Zuwang
Published: July 2023

In the digital age, it is necessary for higher education teachers to improve their digital competence to face the challenges of the advancement of technology. Because there are few studies on the digital competence of higher education teachers in the context of Asia, the aim of this study was to describe Chinese higher education teachers’ self-perceptions of digital competence and investigate the effects of self-efficacy and facilitating conditions and how they predict teachers’ digital competence. For this purpose, a quantitative methodology was used. A final sample of 525 in-service higher education teachers from China completed the questionnaire. The data were analyzed using descriptive analysis, inferential analysis, and latent variable path analysis. The results indicate, first, that teachers’ general perception of digital competence was at a high level, and of the seven competence areas, values, ethics, and security, digital resources, and continuing professional development areas ranked among the top four, respectively, based on their means. Significant differences were observed in the digital competence of teachers with regard to different levels of education, disciplines, and institutional categories. Second, according to the results of structural equation modeling, facilitating conditions were positively and significantly correlated with teachers’ self-efficacy and digital competence. In addition, self-efficacy exerted a significantly positive impact on teachers’ digital competence. Finally, self-efficacy was found to mediate the relationship between facilitating conditions and teachers’ digital competence. Implications are suggested for developing teachers’ digital competence according to the findings of this study.
Current Utilization and Further Application of Zooplankton Indices for Ecosystem Health Assessment of Lake Ecosystems
Authors: Choi Yerim , Oh Hye-Ji , Lee Dae-Hee , Jang Min-Ho , Lee Kyung-Lak , Chang Kwang-Hyeon , Kim Hyun-Woo
Published: July 2023

For the sustainable use of lake ecosystem services—water resources, aquatic habitats for biodiversity conservation, and aesthetic values as waterfront space—ecosystem health assessments using biota are implemented as important national environmental monitoring projects. Zooplankton play a key role as an important linkage in the material circulation as secondary producers in lake ecosystems. At the same time, they influence the composition and biomass of other communities through biological interactions. In this review, we summarize useful zooplankton indices for ecosystem health assessment and suggest considerations for their use. Suggestions are provided for the practical application of indirectly measured zooplankton biomass, as well as the potential and limitations of eDNA application, which has recently been actively utilized in biological monitoring.
Proactive Adaptation Responses by Vulnerable Communities to Climate Change Impacts
Authors: Darjee Kumar Bahadur , Neupane Prem Raj , Köhl Michael
Published: July 2023

We explored the proactive responses of local communities against locally experienced climate change impacts and anticipated threats. This study interviewed 124 rural households from three community forestry user groups representing three ecological regions of Nepal using a semi-structured questionnaire. The study used eight criteria to distinguish the proactive nature of adaptation. Both qualitative and quantitative methods were used to analyze data, including the use of a chi-square (χ2) test to determine the proactive measures and their association with livelihood options and the ordered logistic regression model to explain determining factors of choosing proactive adaptations. The results indicate that 83.9% of households adapted both proactive and reactive measures, while 10.5% applied solely reactive adaptation and 5.6% were earmarked only for proactive adaptation measures. Over 50 different proactive adaptation measures were implemented by the households. The measures were significantly associated with agricultural diversification, cash crop cultivation, livestock raising, small-scale enterprise development, and disaster control. Socio-economic and spatial factors such as a household’s wellbeing, land holding size, geographical location, livelihood options, and the number of adaptation measures implemented by households were found to be decisive factors in choosing proactive adaptation. The study concludes that local people in Nepal are not only aware of escalating climate risks but also engage their cognition and knowledge proactively to adapt locally. The results suggest that even small proactive initiatives by households can offer multiple benefits against climate risks as an architect of individuals. Therefore, adopting a trans-disciplinary approach and nurturing local proactive actions in strategic connectivity between environmental, political, and societal functions is pivotal, which primarily takes a step to drive expediently successful climate change policy and strategy implementation. The findings of this study offer valuable insights into policy and strategy planning for the unsolicited consequences of climate change and highlight the importance of understanding the perspective of local communities in adaptation planning and implementation.