bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Study on the Aerodynamic Characteristics of the NACA 0018 Airfoil at Low Reynolds Number for Darrieus Wind Turbines Using the Transition SST Model
Authors: Rogowski Krzysztof , Królak Grzegorz , Bangga Galih
Published: March 2021

A symmetrical NACA 0018 airfoil is often used in such applications as small-to-medium scale vertical-axis wind turbines and aerial vehicles. A review of the literature indicates a large gap in experimental studies of this airfoil at low and moderate Reynolds numbers in the previous century. This gap has limited the potential development of classical turbulence models, which in this range of Reynolds numbers predict the lift coefficients with insufficiently accurate results in comparison to contemporary experimental studies. Therefore, this paper validates the aerodynamic performance of the NACA 0018 airfoil and the characteristics of the laminar separation bubble formed on its suction side using the standard uncalibrated four-equation Transition SST turbulence model and the unsteady Reynolds-averaged Navier-Stokes (URANS) equations. A numerical study was conducted for the chord Reynolds number of 160,000, angles of attack between 0 and 11 degrees, as well as for the free-stream turbulence intensity of 0.05%. The calculated lift and drag coefficients, aerodynamic derivatives, as well as the location and length of the laminar bubble quite well agree with the results of experimental measurements taken from the literature for validation. A sensitivity study of the numerical model was performed in this paper to examine the effects of the time-step size, geometrical parameters and mesh distribution around the airfoil on the simulation results. The airfoil data sets obtained in this work using the Transition SST and the k-ω SST turbulence models were used in the improved double multiple streamtube (IDMS) to calculate aerodynamic blade loads of a vertical-axis wind turbine. The characteristics of the normal component of the aerodynamic blade load obtained by the Transition SST approach are much better suited to the experimental data compared to the k-ω SST turbulence model.
Process Performance Verification Using Viability Theory
Authors: Zarch Majid Ghaniee , Puig Vicenç , Poshtan Javad , Shoorehdeli Mahdi Aliyari
Published: March 2021

The development of efficient methods for process performance verification has drawn a lot of attention in the research community. Viability theory is a mathematical tool to identify the trajectories of a dynamical system which remains in a constraint set. In this paper, viability theory is investigated for this purpose in the case of nonlinear processes that can be represented in Linear Parameter Varying (LPV) form. In particular, verification algorithms based on the use of invariance and viability kernels and capture basin are proposed. The difficulty with the application of this theory is the computation of these sets. A Lagrangian method has been used to approximate these sets. Because of simplicity and efficient computations, zonotopes are adopted for set representation. Two new sets called Safe Work Area (SWA) and Required Performance (RP) are defined and an algorithm is proposed to use these concepts for the verification purpose. Finally, two application examples based on well-known case studies, a two-tank system and PH neutralization plant, are provided to show the effectiveness of the proposed method.
Toxicological and Epigenetic Studies of Two Types of Ale Beer, Tyrosol and Iso-Alpha Humulone
Authors: Merinas-Amo Tania , Merinas-Amo Rocío , Font Rafael , del Río Celestino Mercedes , Alonso-Moraga Ángeles
Published: March 2021

Although many benefits drawn from beer consumption are claimed, the epidemiological records are contradictory with respect to cancer prevention. The purpose of this study was to investigate the possible health-related activities involving genome safety and the ageing processes of two types of lyophilised ale beers (blond and stout), as well as two of their bioactive compounds (tyrosol and iso-alpha humulone). A multipurpose trial set of in vivo toxicity, antitoxicity, mutagenicity, antimutagenicity, lifespan and healthspan assays using Drosophila melanogaster were used. In parallel, several in vitro assays were designed using the cancer cell line HL-60 in order to establish the possible chemopreventive activity of the selected substances, where epigenetic modulation of DNA methylation changes, clastogenic activity and tumour cell inhibition growth were evaluated. The safety of the four substances was confirmed: lyophilised blond ale beer (LBAB), lyophilised stout ale beer (LSAB), tyrosol and iso-alpha humulone were neither toxic nor genotoxic. Moreover, all substances, except tyrosol, revealed the ability to protect individual genomes against oxidative radicals and to exert antimutagenic activity against the genotoxin hydrogen peroxide. With respect to the degenerative process indicators of lifespan and healthspan, tyrosol was the only compound that did not exert any influence on the life extension of Drosophila; LBAB induced a significant lifespan extension in D. melanogaster; LSAB and its distinctive compound iso-alpha humulone induced a reduction in longevity. The in vitro assays showed the cytotoxic activity of LBAB, LSAB and tyrosol against HL-60 cells. Moreover, proapoptotic DNA fragmentation or DNA strand breakage was observed for both types of beers and iso-alpha humulone at different concentrations. Furthermore, the lyophilised ale beers and tyrosol exhibited an increasing genome-wide methylation status, while iso-alpha humulone exhibited a demethylation status in repetitive cancer cell sequences. Although the biological activities assigned to beer consumption cannot be linked to any specific molecule/element due to the complexity of the phenolic profile, as well as the multifactor brewing process, the results obtained let us propose lyophilised ale beers as safe potential nutraceutical beverages when consumed in moderate amounts. The prevention of toxicity and genetic oxidative damage, as well as the induction of tumor cell death and modulation of the methylation status, are the key activities of beer that were shown in the present research.
The Effect of Recycled HDPE Plastic Additions on Concrete Performance
Authors: Tamrin  , Nurdiana Juli
Published: March 2021

This study examined HDPE (high-density polyethylene) plastic waste as an added material for concrete mixtures. The selection of HDPE was based on its increased strength, hardness, and resistance to high temperatures compared with other plastics. It focused on how HDPE plastic can be used as an additive in concrete to increase its tensile strength and compressive strength. 156 specimens were used to identify the effect of adding different percentages and sizes of HDPE lamellar particles to lower, medium, and higher strength concrete for non-structural applications. HDPE 0.5 mm thick lamellar particles with sizes of 10 × 10 mm, 5 × 20 mm, and 2.5 × 40 mm were added at 2.5%, 5%, 10%, and 20% by weight of cement. The results showed that the medium concrete class (with compressive strength equal to 10 MPa) had the best response to the addition of HDPE. The 5% HDPE addition represented the optimal mix for all concrete types, while the 5 × 20 mm size was best.
A Lidar-Based 3-D Photosynthetically Active Radiation Model Reveals the Spatiotemporal Variations of Forest Sunlit and Shaded Leaves
Authors: Tian Shihao , Zheng Guang , Eitel Jan U. , Zhang Qian
Published: March 2021

Accurately identifying sunlit and shaded leaves using process-based ecological models can improve the simulation accuracy of forest photosynthetic rates and potential carbon sequestration capacity. However, it is still challenging to characterize their three dimensional (3-D) spatiotemporal distributions due to the complex structure. In this study, we developed a light detection and ranging (lidar)-based approach to map the spatiotemporal distribution patterns of photosynthetically active radiation (PAR) and sunlit and shaded leaves within forest canopies. By using both terrestrial laser scanning (TLS) and unmanned aerial vehicle-based lidar system (UAV-LS), we analyzed the influences of different scanning geometries and associated point densities on the separation of sunlit and shaded leaves. Moreover, we further investigated the effects of woody materials and penumbra sizes on identifying sunlit and shaded leaves by separating the foliage and woody materials and estimating the penumbras of sunlit leaves. Our results showed that: (1) The proposed lidar-based PAR model could well capture the variations of field-based pyranometer measurements using fused point data by combining UAV-LS and TLS data (mean R-square = 0.88, mean root mean square error (RMSE) = 155.5 μmol·m−2·s−1, p < 0.01). The separate UAV-LS and TLS-based fractions of sunlit leaves were averagely overestimated by 34.3% and 21.6% when compared to the fused point data due to their different coverages and comprehensiveness. (2) The woody materials showed different effects on sunlit leaf fraction estimations for forest overstory and understory due to the variations of solar zenith angle and tree spatial distribution patterns. The most noticeable differences (i.e., −36.4%) between the sunlit leaf fraction before and after removing woody materials were observed around noon, with a small solar zenith angle and low-density forest stand. (3) The penumbra effects were seen to increase the sunlit leaf fraction in the lower canopy by introducing direct solar radiation, and it should be considered when using 3-D structural information from lidar to identify sunlit and shaded leaves.
Ionosonde Observations of Spread F and Spread Es at Low and Middle Latitudes during the Recovery Phase of the 7–9 September 2017 Geomagnetic Storm
Authors: Wei Lehui , Jiang Chunhua , Hu Yaogai , Aa Ercha , Huang Wengeng , Liu Jing , Yang Guobin , Zhao Zhengyu
Published: March 2021

This study presents observations of nighttime spread F/ionospheric irregularities and spread Es at low and middle latitudes in the South East Asia longitude of China sectors during the recovery phase of the 7–9 September 2017 geomagnetic storm. In this study, multiple observations, including a chain of three ionosondes located about the longitude of 100°E, Swarm satellites, and Global Navigation Satellite System (GNSS) ROTI maps, were used to study the development process and evolution characteristics of the nighttime spread F/ionospheric irregularities at low and middle latitudes. Interestingly, spread F and intense spread Es were simultaneously observed by three ionosondes during the recovery phase. Moreover, associated ionospheric irregularities could be observed by Swarm satellites and ground-based GNSS ionospheric TEC. Nighttime spread F and spread Es at low and middle latitudes might be due to multiple off-vertical reflection echoes from the large-scale tilts in the bottom ionosphere. In addition, we found that the periods of the disturbance ionosphere are ~1 h at ZHY station, ~1.5 h at LSH station and ~1 h at PUR station, respectively. It suggested that the large-scale tilts in the bottom ionosphere might be produced by LSTIDs (Large scale Traveling Ionospheric Disturbances), which might be induced by the high-latitude energy inputs during the recovery phase of this storm. Furthermore, the associated ionospheric irregularities observed by satellites and ground-based GNSS receivers might be caused by the local electric field induced by LSTIDs.
Research Gap Analysis of Remote Sensing Application in Fisheries: Prospects for Achieving the Sustainable Development Goals
Authors: Yen Kuo-Wei , Chen Chia-Hsiang
Published: March 2021

Remote sensing (RS) technology, which can facilitate the sustainable management and development of fisheries, is easily accessible and exhibits high performance. It only requires the collection of sufficient information, establishment of databases and input of human and capital resources for analysis. However, many countries are unable to effectively ensure the sustainable development of marine fisheries due to technological limitations. The main challenge is the gap in the conditions for sustainable development between developed and developing countries. Therefore, this study applied the Web of Science database and geographic information systems to analyze the gaps in fisheries science in various countries over the past 10 years. Most studies have been conducted in the offshore marine areas of the northeastern United States of America. In addition, all research hotspots were located in the Northern Hemisphere, indicating a lack of relevant studies from the Southern Hemisphere. This study also found that research hotspots of satellite RS applications in fisheries were mainly conducted in (1) the northeastern sea area in the United States, (2) the high seas area of the North Atlantic Ocean, (3) the surrounding sea areas of France, Spain and Portugal, (4) the surrounding areas of the Indian Ocean and (5) the East China Sea, Yellow Sea and Bohai Bay sea areas to the north of Taiwan. A comparison of publications examining the three major oceans indicated that the Atlantic Ocean was the most extensively studied in terms of RS applications in fisheries, followed by the Indian Ocean, while the Pacific Ocean was less studied than the aforementioned two regions. In addition, all research hotspots were located in the Northern Hemisphere, indicating a lack of relevant studies from the Southern Hemisphere. The Atlantic Ocean and the Indian Ocean have been the subjects of many local in-depth studies; in the Pacific Ocean, the coastal areas have been abundantly investigated, while offshore local areas have only been sporadically addressed. Collaboration and partnership constitute an efficient approach for transferring skills and technology across countries. For the achievement of the sustainable development goals (SDGs) by 2030, research networks can be expanded to mitigate the research gaps and improve the sustainability of marine fisheries resources.
Evaluation of Three Different Machine Learning Methods for Object-Based Artificial Terrace Mapping—A Case Study of the Loess Plateau, China
Authors: Ding Hu , Na Jiaming , Jiang Shangjing , Zhu Jie , Liu Kai , Fu Yingchun , Li Fayuan
Published: March 2021

Artificial terraces are of great importance for agricultural production and soil and water conservation. Automatic high-accuracy mapping of artificial terraces is the basis of monitoring and related studies. Previous research achieved artificial terrace mapping based on high-resolution digital elevation models (DEMs) or imagery. As a result of the importance of the contextual information for terrace mapping, object-based image analysis (OBIA) combined with machine learning (ML) technologies are widely used. However, the selection of an appropriate classifier is of great importance for the terrace mapping task. In this study, the performance of an integrated framework using OBIA and ML for terrace mapping was tested. A catchment, Zhifanggou, in the Loess Plateau, China, was used as the study area. First, optimized image segmentation was conducted. Then, features from the DEMs and imagery were extracted, and the correlations between the features were analyzed and ranked for classification. Finally, three different commonly-used ML classifiers, namely, extreme gradient boosting (XGBoost), random forest (RF), and k-nearest neighbor (KNN), were used for terrace mapping. The comparison with the ground truth, as delineated by field survey, indicated that random forest performed best, with a 95.60% overall accuracy (followed by 94.16% and 92.33% for XGBoost and KNN, respectively). The influence of class imbalance and feature selection is discussed. This work provides a credible framework for mapping artificial terraces.
Threat Modeling—How to Visualize Attacks on IOTA?
Authors: Ullah Ikram , de Roode Gerard , Meratnia Nirvana , Havinga Paul
Published: March 2021

Internet of Things (IoT) has been deployed in a vast number of smart applications with the aim to bring ease and comfort into our lives. However, with the expansion of IoT applications, the number of security and privacy breaches has also increased, which brings into question the resilience of existing security and trust mechanisms. Furthermore, the contemporaneous centralized technology is posing significant challenges viz scalability, transparency and efficiency to wide range of IoT applications such as smart logistics, where millions of IoT devices need to be connected simultaneously. Alternatively, IOTA is a distributed ledger technology that offers resilient security and trust mechanisms and a decentralized architecture to overcome IoT impediments. IOTA has already been implemented in many applications and has clearly demonstrated its significance in real-world applications. Like any other technology, IOTA unfortunately also encounters security vulnerabilities. The purpose of this study is to explore and highlight security vulnerabilities of IOTA and simultaneously demonstrate the value of threat modeling in evaluating security vulnerabilities of distributed ledger technology. IOTA vulnerabilities are scrutinized in terms of feasibility and impact and we have also presented prevention techniques where applicable. To identify IOTA vulnerabilities, we have examined existing literature and online blogs. Literature available on this topic is very limited so far. As far as we know IOTA has barely been addressed in the traditional journals, conferences and books. In total we have identified six vulnerabilities. We used Common Vulnerability Scoring System (CVSS v3.0) to further categorize these vulnerabilities on the basis of their feasibility and impact.
A Novel Location Source Optimization Algorithm for Low Anchor Node Density Wireless Sensor Networks
Authors: Deng Zhongliang , Tang Shihao , Deng Xiwen , Yin Lu , Liu Jingrong
Published: March 2021

Location information is one of the basic elements of the Internet of Things (IoT), which is also an important research direction in the application of wireless sensor networks (WSNs). Aiming at addressing the TOA positioning problem in the low anchor node density deployment environment, the traditional cooperative localization method will reduce the positioning accuracy due to excessive redundant information. In this regard, this paper proposes a location source optimization algorithm based on fuzzy comprehensive evaluation. First, each node calculates its own time-position distribute conditional posterior Cramer-Rao lower bound (DCPCRLB) and transfers it to neighbor nodes. Then collect the DCPCRLB, distance measurement, azimuth angle and other information from neighboring nodes to form a fuzzy evaluation factor set and determine the final preferred location source after fuzzy change. The simulation results show that the method proposed in this paper has better positioning accuracy about 33.9% with the compared method in low anchor node density scenarios when the computational complexity is comparable.
Representation and Agency of Aging Superheroes in Popular Culture and Contemporary Society
Authors: Valentová Kateřina
Published: March 2021

The figure of the superhero has always been regarded as an iconic representative of American society. Since the birth of the first superhero, it has been shaped by the most important historical, political, and social events, which were echoed in different comic issues. In principle, in the superhero genre, there has never been a place for aging superheroes, for they stand as a symbol of power and protection for the nation. Indeed, their mythical portrayal of young and strong broad-chested men with superpowers cannot be shattered showing them fragile or disabled. The aim of this article is to delve into the complex paradigm of the passage of time in comics and to analyze one of the most famous superheroes of all times, Superman, in terms of his archetypical representation across time. From the perspective of cultural and literary gerontology, the different issues of Action Comics will be examined, as well as an alternative graphic novel Kingdom Come (2008) by Mark Waid and Alex Ross, where Superman appears as an aged man. Although it breaks the standards of the genre, in the end it does not succeed to challenge the many stereotypes embedded in society in regard to aging, associated with physical, cognitive, and emotional decline. Furthermore, this article will show how a symbolic use of the monomythical representation of a superhero may penetrate into other cultural expressions to instill a more positive and realistic portrayal of aging.
Digitalization of Critical Reflection with ATLAS.ti Software in Social Work Supervision
Authors: Rambaree Komalsingh , Nässén Nessica
Published: March 2021

In this technology-driven era, the digitalization of social work practice is becoming almost mandatory in many countries, especially in Europe. Within this context, it is important to look at the possibilities and challenges for the digitalization of critical reflection, which is a fundamental part of social work practice. Using a conceptual and theoretical framework based on reflective practice, critical reflection, and experiential learning, this article aims to outline and discuss the use of ATLAS.ti software as a supporting tool in digitalizing critical reflection in social work supervision (SWS). For illustrative purposes, a case example of child welfare from Sweden is used. This article considers both the benefits and challenges of using ATLAS.ti as a technological tool for the digitalization of critical reflection in SWS. It concludes that social workers’ autonomy and wellbeing need to be at the center in deciding about the use of digital tools such as ATLAS.ti in SWS.
Effect of Player Role and Competition Level on Player Demands in Basketball
Authors: Palmer Jodie , Wundersitz Daniel , Bini Rodrigo , Kingsley Michael
Published: March 2021

This study compared basketball training and match demands between player roles (starters, in-rotation bench players, out-rotation bench players) and between competition levels (semi-professional, professional). Thirty-seven players from one professional women’s team, one semi-professional women’s team, and one semi-professional men’s team wore accelerometers during training and matches throughout a competitive season. All teams were used for player role comparisons and the women’s teams were used to compare competition levels. Match and training session average intensity and volume, and durations of relative exercise intensities (inactive, light, moderate-vigorous, maximal, supramaximal) were calculated. Compared to out-rotation bench players, starters experienced twice the average match intensity and volume, spent 50% less match time being inactive, and spent 1.7–4.2× more match time in all other activity categories (p < 0.01). Compared to in-rotation bench players, starters experienced 1.2× greater average match intensity and volume, spent 17% less match time being inactive, and spent 1.4–1.5× more match time performing moderate-vigorous and maximal activity (p < 0.01). No differences in match demands were found between women’s competition levels, however the professional team experienced double the cumulative weekly training volume of the semi-professional team and spent 1.6–2.1× more cumulative weekly time in all activity categories (p < 0.01). To improve performance and reduce injury risk, players should prepare for the greatest match demands they could encounter during a season while considering potential changes to their role. Additionally, players might need their training volume managed when transitioning from a semi-professional to a professional season to reduce the injury risk from sharp increases in training demands.
Integrating Environmental Impact and Ecosystem Services in the Process of Land Resource Capitalization—A Case Study of Land Transfer in Fuping, Hebei
Authors: Fan Weiguo , Chen Nan , Yao Wei , Meng Mengmeng , Wang Xuechao
Published: March 2021

The contradiction between human and land has always been a problem in the process of development and utilization of land resources. Under such circumstances, relevant government agencies put forward the management concept of land resource capitalization. As an effective policy to implement the conception of land resource capitalization, land transfer is of great significance to reforming rural land systems and liberating productivity in poor areas of Tai-hang Mountain in Hebei. However, how to integrate environmental impact and value evaluation of ecosystem services of land transfer in the process of resource capitalization deserves our attention. This paper takes the land transfer of Fuping, Hebei in Tai-hang Mountain as an example, combined with life cycle assessment (LCA), life cycle cost assessment (LCC), and the methods of value evaluation of ecosystem services to quantify the changes of environmental loads, economic costs, and ecosystem services in the whole process and different stages of land resource capitalization. Moreover, through the sensitivity analysis of key environmental indicators, the possibility of restricting environmental costs is explored. This paper studies land transfer from the direction of the cross-discipline and provides a new idea for land resource management.
Empirical Analysis on the Performance of Rural Credit Cooperative’s Shareholding Reform Based on the Rationale of Isomorphic Incentive Compatibility
Authors: Hu Yue , Lu Siwei , Zhang Huiyuan , Liu Guibo , Peng Jiangang
Published: March 2021

Rural economic development helps reduce the income inequality in China. Existing studies show the positive effects of rural reforms, however, whether the rural credit cooperative’s shareholding reform promotes rural economic development and whether effects are exerted through the synergism between agricultural producers and rural financial institutions remain unclear yet. Employing the rationale of isomorphic incentive compatibility from system science, we analyze the necessity and influencing conduit of rural credit cooperative’s shareholding reform theoretically. Analysis shows that only the financial services from rural commercial banks can promote the modernized production, and thus the synergism between them drives rural economic development. Then we make empirical analysis on the effect with a Chinese provincial sample. Comparing to provinces with lower reform progress, the provinces with greater reform progress are influenced more prominently by this reform. Applying coupling coordination degree model, the coordination between agricultural production and rural banking development shows obvious increase, especially after the formal implementation of shareholding reform on rural credit cooperative. Empirical results indicate that this synergism plays positive roles in promoting agricultural growth and reducing the urban–rural income gap. In addition, these effects are more pronounced after the formal implementation of shareholding reform.
Application of Mathematical and Computational Methods to Identify Women’s Priorities in Transport
Authors: Poveda-Reyes Sara , Malviya Ashwani Kumar , García-Jiménez Elena , Molero Gemma Dolores , Leva Maria Chiara , Santarremigia Francisco Enrique
Published: March 2021

It is well established that the transport sector is not an equalitarian sector. To develop a sustainable society, a more equalitarian and safe transport system for both users and transport sector employees is needed. This work prioritizes the needs and barriers previously identified as relevant among transport system users and employees for four different transport scenarios (railways, autonomous vehicles (AVs), bicycle-sharing services (BSSs), and employment). The aim of this paper is to prioritize the factors affecting women in these four transport scenarios with the help of a survey followed by the application of mathematical and computational algorithms based on the analytic hierarchy process (AHP) methodology. The identification of factors with higher influence in the fair participation of women in the transport sector will help transport planners, bike-sharing system owners, decision-makers, transport companies, and regulatory professionals to develop measures that could plausibly increase the proportion of women as users of BSSs, users of rail public transport, and AVs, as well as employees in the transport sector for a sustainable society. The results indicated that safety and security were the most challenging factors for railways. Weather, topography, and family responsibilities were shown to have a high influence on the use of BSSs. In the case of autonomous vehicles, the simultaneity and trust in the technology are the main opportunities to influence the acceptance of such vehicles. Finally, for transport employment, caring and parenting responsibilities were the factors that had the largest effect. Some differences in priorities were found for different profiles of women.
Does Financial Development Promote the Growth of Property Income of China’s Urban and Rural Residents?
Authors: Peng Xiaozhun , Lu Hongyou , Fu Jiaming , Li Zhijuan
Published: March 2021

The property income growth of urban and rural residents is an important part of the continuous increase in the disposable income of these residents, which is also inseparable from the deepening development of the financial market. After sorting out the various sources of income that affect residents’ property in the existing research and controlling regional fixed effects, based on data from 31 provinces in China, this article considers important financial factors and the process of urbanization as explanatory variables to perform panel regression on the property income of provincial residents under fixed effects and random effects. In the context of large differences in the investment environment between urban and rural areas, we further examine the effects of financial factors on the property income of urban and rural residents. Only by expanding the investment opportunities and enhancing the investment ability of the residents, can the property income of the residents, especially the rural residents, be guaranteed to grow steadily and sustainably.
Preserving the Integrity of Social Impact Investing: Towards a Distinctive Implementation Strategy
Authors: Bengo Irene , Borrello Alice , Chiodo Veronica
Published: March 2021

Social impact investing (SII) is a strategy of asset allocation that aims to generate social and environmental impact alongside a financial return. Compared to other approaches of sustainable finance it holds an enormous potential of generating solutions to societal challenges. However, scholars have claimed that social impact often just employs logic upheld by the mainstream investment approach. Therefore, the paper investigates the assumption that SII has not developed a distinctive implementation strategy able to translate the prioritization of social impact into practice and how to overcome this issue. The thematic analysis of data collected through 105 interviews with Italian SII financiers and the top managers of social ventures allowed us to identify three features of an SII tailored practice: promoting a cultural shift of intermediaries, adopting a coopetition approach, and integrating the social impact in the terms of the financial transaction. Lastly, the paper drafts a research agenda to enhance the proper theorization of SII focusing on the definition of social risk, social return, and governance mechanisms. The key contribution of this article is confirming the lack of an SII-specific practice able to endogenize the intent of prioritizing social impact and providing suggestions to prevent the risk of impact washing.
Agile-Based Education for Teaching an Agile Requirements Engineering Methodology for Knowledge Management
Authors: Levy Meira , Hadar Irit , Aviv Itzhak
Published: March 2021

The importance of the role that knowledge management (KM) plays in the success of knowledge-intensive organizations has long been acknowledged. However, requirements engineering (RE) methods for KM solutions still lack maturity, as do the educational programs in this domain. In this paper, an agile-based educational method for teaching RE for KM solutions, specifically an agile KM RE methodology (AKM-REM), is proposed. The paper reports a teaching experience, in which 17 teams of graduate students learned and implemented AKM-REM, each in a different real-life case study. Data were collected via class observations and from the students’ submitted projects and underwent qualitative content analysis. The findings demonstrate the manner in which AKM-REM creates a culture of collaboration, trust, and reflection, fostering the dynamic and flexible organization that is required in today’s competitive business environment. The contribution of this paper is fourfold. First, it presents an extension of the research on agile-based RE for KM solutions as a specialized area. Second, it presents an extension of an existing method KM-REM along the agile principles. Third, it provides means for agile-based education for analyzing and addressing KM challenges effectively. Finally, it describes the importance of agile KM RE in the context of sustainability.
Human–River Encounter Sites: Looking for Harmony between Humans and Nature in Cities
Authors: Zingraff-Hamed Aude , Bonnefond Mathieu , Bonthoux Sebastien , Legay Nicolas , Greulich Sabine , Robert Amélie , Rotgé Vincent , Serrano José , Cao Yixin , Bala Raita , Vazha Alvin , Tharme Rebecca E. , Wantzen Karl M.
Published: March 2021

Human welfare depends on the health of nature. Decades of ill-conceived management practices caused a decline in the quality of human life, as well as in biological and cultural diversity. Simultaneously, they increased social and ecological risks. For instance, mismanagement of urban rivers jeopardizes their ecological health and ability to provide ecosystem services. While demands for responsible urban riverscape design that fulfill both human and ecosystem needs are increasing, explicit recommendations to achieve these ambitious goals are still lacking. We present a first attempt of a conceptualization of Human–River Encounter Sites for urban rivers that targets reconciliation between humans and nature within urban river corridors. It builds upon the River Culture Concept with literature reviews and experiences from river restoration projects. We identify six tenets that are important to develop guidelines for Human–River Encounter Sites: health, safety, functionality, accessibility, collaboration, and awareness. This paper presents how these tenets can collectively help to harmonize the needs of citizens and biota, and to mitigate the current urban river crisis. This contribution feeds the debate on sustainable socio-ecological management of urban rivers and provides guidelines for the implementation of future urban river restorations and management efforts.
The Sustainability of Thailand’s Protected-Area System under Climate Change
Authors: Pomoim Nirunrut , Zomer Robert J. , Hughes Alice C. , Corlett Richard T.
Published: March 2021

Protected areas are the backbone of biodiversity conservation but vulnerable to climate change. Thailand has a large and well-planned protected area system, covering most remaining natural vegetation. A statistically derived global environmental stratification (GEnS) was used to predict changes in bioclimatic conditions across the protected area system for 2050 and 2070, based on projections from three CMIP5 earth system models and two representative concentration pathways (RCPs). Five bioclimatic zones were identified composed of 28 strata. Substantial spatial reorganization of bioclimates is projected in the next 50 years, even under RCP2.6, while under RCP8.5 the average upward shift for all zones by 2070 is 328–483 m and the coolest zone disappears with two models. Overall, 7.9–31.0% of Thailand’s land area will change zone by 2070, and 31.7–90.2% will change stratum. The consequences for biodiversity are less clear, particularly in the lowlands where the existing vegetation mosaic is determined largely by factors other than climate. Increasing connectivity of protected areas along temperature and rainfall gradients would allow species to migrate in response to climate change, but this will be difficult in much of Thailand. For isolated protected areas and species that cannot move fast enough, more active, species-specific interventions may be necessary.
Exposing Emerging Trends in Smart Sustainable City Research Using Deep Autoencoders-Based Fuzzy C-Means
Authors: Parlina Anne , Ramli Kalamullah , Murfi Hendri
Published: March 2021

The literature discussing the concepts, technologies, and ICT-based urban innovation approaches of smart cities has been growing, along with initiatives from cities all over the world that are competing to improve their services and become smart and sustainable. However, current studies that provide a comprehensive understanding and reveal smart and sustainable city research trends and characteristics are still lacking. Meanwhile, policymakers and practitioners alike need to pursue progressive development. In response to this shortcoming, this research offers content analysis studies based on topic modeling approaches to capture the evolution and characteristics of topics in the scientific literature on smart and sustainable city research. More importantly, a novel topic-detecting algorithm based on the deep learning and clustering techniques, namely deep autoencoders-based fuzzy C-means (DFCM), is introduced for analyzing the research topic trend. The topics generated by this proposed algorithm have relatively higher coherence values than those generated by previously used topic detection methods, namely non-negative matrix factorization (NMF), latent Dirichlet allocation (LDA), and eigenspace-based fuzzy C-means (EFCM). The 30 main topics that appeared in topic modeling with the DFCM algorithm were classified into six groups (technology, energy, environment, transportation, e-governance, and human capital and welfare) that characterize the six dimensions of smart, sustainable city research.
Changing Effect of Urban Form on the Seasonal and Diurnal Variations of Surface Urban Heat Island Intensities (SUHIIs) in More Than 3000 Cities in China
Authors: Ma Lin , Wang Yueyao , Liang Ze , Ding Jiaqi , Shen Jiashu , Wei Feili , Li Shuangcheng
Published: March 2021

Based on the indicators of more than 3000 cities in China, this study shows that the relationship between the urban form and surface urban heat island intensity (SUHII) demonstrates seasonal and diurnal variations, and also changes along urban development and elevation gradients. SUHIIs show seasonal and diurnal change patterns along urban development and elevation gradients, but there is no obvious change trend along temperature and humidity gradients. Among them, the seasonal variation of the SUHII went up about 0.4 ℃ from the first level of urban development to the highest level, while the diurnal variation of the SUHII decreased by 0.4 °C. With urban development, the correlations between the anthropogenic heat flux (AHF), population density (POPDEN) and morphological continuity (CONTIG) with the SUHII of summer days, summer nights and winter nights continued to be enhanced, with the correlation coefficients (β) increased by about 0.3. The effect of area size (AREA) became more influential on the SUHII of summer days and nights, but its effect on the SUHII of winter nights increased first and then decreased along the urban development gradient. With the increase of elevation, the correlations of the AHF, POPDEN, AREA, CONTIG and summer day and night SUHII were gradually reduced (β decreased by about 0.4), but their impact on the SUHII of winter nights was gradually enhanced (β increased by about 0.2 to 0.3). Along temperature and humidity gradients, the positive effect of POPDEN on the summer SUHII decreased gradually (β decreased by about 0.3). However, the enhancement effects of the AHF, AREA, CONTIG and POPDEN on the SUHII of winter nights increased generally (β increased by about 0.2). According to the Random Forest model, for the SUHIIs at night, the relative importance (RI) of urban form factors was greater, while for the SUHIIs of daytime, the RIs of natural factors were greater. The contribution of the urban form to the seasonal variation of the SUHII is similar to that of natural factors, but their contribution to diurnal variation is lower. Our results suggest that it is more necessary to control the urban scale, avoid excessive urban agglomeration and reasonably control the anthropogenic heat emission in more developed and low altitude cities to reduce their summer heat exposure.
The Effect of Variable-Length Fins and Different High Thermal Conductivity Nanoparticles in the Performance of the Energy Storage Unit Containing Bio-Based Phase Change Substance
Authors: Ghalambaz Mohammad , Mehryan Seyed Abdollah Mansouri , Mozaffari Masoud , Younis Obai , Ghosh Aritra
Published: March 2021

Thermal Energy Storage (TES) is a key feature in the sizing of thermal systems and energy management. The Phase Change Material (PCM) can store a huge amount of heat in the form of latent heat. However, a good design of the TES unit is required to absorb thermal energy and charge quickly. In the present study, a combination of optimum fin design and nanoadditives are used to design a shell and tube shape TES unit. The Taguchi optimization method is employed to maximize the melting rate by optimizing the arrangement shape of fins and the type and the volume fractions of nanoparticles. The results showed that long fins should be mounted at the bottom and short fins at the top, so that the PCM melts down at the bottom quickly, and consequently, a natural convection circulation occurs at the bottom and advances in the solid PCM. The short fins at the top allow a good natural convection circulation at the top. An increase in the volume fraction of nanoparticles increases the melting rate. An optimum design shows a 20% more melting rate compared to a poor design.
Knowledge-Based Economy Capacity Building for Developing Countries: A Panel Analysis in Southern African Development Community
Authors: Phale Koketso , Li Fanglin , Adjei Mensah Isaac , Omari-Sasu Akoto Yaw , Musah Mohammed
Published: March 2021

The Southern African Development Community is lagging behind in terms of knowledge economy relative to other regions worldwide. This dramatically reduces the chances of keeping up with their economically established counterparts in terms of sustainable development. This paper therefore, applies multivariate panel data analysis which is predicted on the Cobb–Douglas production function to analyze the affiliation flanked by knowledge-based economy pillars and economic growth from 1998–2018. The World Bank knowledge-based economy framework is employed. To achieve the study goal, the long-run effect regarding proxies of each pillar in the knowledge-based economy on economic growth is first estimated. Afterwards, the average impact of each pillar is examined using the average impact index (AII). Employment of both conventional unit root and co-integration tests showed all observed series are stationary and co-integrated. Further estimation of the long-run relationship using both static and dynamic models (fixed effect and generalized method of moment) portrayed that government effectiveness, adjusted savings on education expenditure, tertiary enrollment, scientific and technical journals, and mobile cellular subscriptions have significant positive impact on economic growth. Finally, the AII estimation unveiled that the innovation pillar is the most impactful aspect on economic growth followed by education and skills with the least being information and communication technology infrastructure. Feasible policy recommendations are further suggested.
Development of a Spatial Model for Soil Quality Assessment under Arid and Semi-Arid Conditions
Authors: Shokr Mohamed S. , Abdellatif Mostafa. A. , El Baroudy Ahmed A. , Elnashar Abdelrazek , Ali Esmat F. , Belal Abdelaziz A. , Attia Wael. , Ahmed Mukhtar , Aldosari Ali A. , Szantoi Zoltan , Jalhoum Mohamed E. , Kheir Ahmed M. S.
Published: March 2021

Food security has become a global concern for humanity with rapid population growth, requiring a sustainable assessment of natural resources. Soil is one of the most important sources that can help to bridge the food demand gap to achieve food security if well assessed and managed. The aim of this study was to determine the soil quality index (SQI) for El Fayoum depression in the Western Egyptian Desert using spatial modeling for soil physical, chemical, and biological properties based on the MEDALUS methodology. For this purpose, a spatial model was developed to evaluate the soil quality of the El Fayoum depression in the Western Egyptian Desert. The integration between Digital Elevation Model (DEM) and Sentinel-2 satellite image was used to produce landforms and digital soil mapping for the study area. Results showed that the study area located under six classes of soil quality, e.g., very high-quality class represents an area of 387.12 km2 (22.7%), high-quality class occupies 441.72 km2 (25.87%), the moderate-quality class represents 208.57 km2 (12.21%), slightly moderate-quality class represents 231.10 km2 (13.5%), as well as, a low-quality class covering an area of 233 km2 (13.60%), and very low-quality class occupies about 206 km2 (12%). The Agricultural Land Evaluation System for arid and semi-arid regions (ALESarid) was used to estimate land capability. Land capability classes were non-agriculture class (C6), poor (C4), fair (C3), and good (C2) with an area 231.87 km2 (13.50%), 291.94 km2 (17%), 767.39 km2 (44.94%), and 416.07 km2 (24.4%), respectively. Land capability along with the normalized difference vegetation index (NDVI) used for validation of the proposed model of soil quality. The spatially-explicit soil quality index (SQI) shows a strong significant positive correlation with the land capability and a positive correlation with NDVI at R2 0.86 (p < 0.001) and 0.18 (p < 0.05), respectively. In arid regions, the strategy outlined here can easily be re-applied in similar environments, allowing decision-makers and regional governments to use the quantitative results achieved to ensure sustainable development.
An Empirical Test of Mobile Service Provider Promotions on Repurchase Intentions
Authors: Ji Kwangchul , Ha Hong-Youl
Published: March 2021

Little empirical evidence is obtained for the moderating outcomes of mobile promotions (M-promotions) during subsequent repurchasing events. This study examines how M-promotions indirectly influence repurchase intentions, and how the level of promotions moderates the relationship between repurchase intentions and their determinants. The findings show that three determinants (i.e., brand attitude, functional quality, and online reviews) directly lead to repurchase intention. However, the moderating effects of M-promotions vary. Especially, our findings show that the moderating effect of M-promotions is only significant in the relationship between functional quality and repurchase intentions and that between online reviews and repurchase intentions. Repurchase intentions are increased by high M-promotions when functional quality is low, and when online reviews are positive.