bluuebunny/crossref_metadata_2025 huggingface dataset:
System Design of a Vehicle Based on the Matrix Approach Using Functional Analysis of the Maintenance
Authors: Mežnar Dušan
Published: May 2021

The use of extended standard functional analysis of maintenance in the design phase of vehicle structure analysis is presented for the first time, where a matrix of the degree of importance of modules or parts, a matrix size between costs and benefits (costs–benefits), and a logistic support matrix (support index and repair time) are used. The use of these methods allows a designer to be able to determine, in the very early phase of the construction process, the important factors (structure, component price, reliability, repair costs, response time, logistic supportability) that have a major impact on vehicle maintenance. Extended functional analysis also allows us to define critical structures in the project specification of vehicles. A crucial issue in functional analysis is the very extensive implementation of research, drawing conclusions and findings with the basic goal of determining a set of indicators for the verification of assumptions and hypotheses.
Recycling Potential for Non-Valorized Plastic Fractions from Electrical and Electronic Waste
Authors: Strobl Laura , Diefenhardt Thomas , Schlummer Martin , Leege Tanja , Wagner Swetlana
Published: May 2021

This paper describes a study for waste of electrical and electronic equipment (WEEE) to characterise the plastic composition of different mixed plastic fractions. Most of the samples studied are currently excluded from material recycling and arise as side streams in state-of-the-art plastics recycling plants. These samples contain brominated flame retardants (BFR) or other substances of concern listed as persistent organic pollutants or in the RoHS directive. Seventeen samples, including cathode ray tube (CRT) monitors, CRT televisions, flat screens such as liquid crystal displays, small domestic appliances, and information and communication technology, were investigated using density- and dissolution-based separation processes. The total bromine and chlorine contents of the samples were determined by X-ray fluorescence spectroscopy, indicating a substantial concentration of both elements in density fractions above 1.1 g/cm3, most significantly in specific solubility classes referring to ABS and PS. This was further supported by specific flame retardant analysis. It was shown that BFR levels of both polymers can be reduced to levels below 1000 ppm by dissolution and precipitation processes enabling material recycling in compliance with current legislation. As additional target polymers PC and PC-ABS were also recycled by dissolution but did not require an elimination of BFR. Finally, physicochemical investigations of recycled materials as gel permeation chromatography, melt flow rate, and differential scanning calorimetry suggest a high purity and indicate no degradation of the technical properties of the recycled polymers.
The Bohemian Brethren and the Protestant Reformation
Authors: Atwood Craig
Published: May 2021

The smallest, but in some ways the most influential, church to emerge from the Hussite Reformation was the Unity of the Brethren founded by Gregory the Patriarch in 1457. The Unity was a voluntary church that separated entirely from the established churches, and chose its own priests, published the first Protestant hymnal and catechism, and operated several schools. Soon after Martin Luther broke with Rome, the Brethren established cordial relations with Wittenberg and introduced their irenic and ecumenical theology to the Protestant Reformation. Over time, they gravitated more toward the Reformed tradition, and influenced Martin Bucer’s views on confirmation, church discipline, and the Eucharist. In many ways, the pacifist Brethren offered a middle way between the Magisterial Reformation and the Radical Reformation. Study of the Brethren complicates and enhances our understanding of the Protestant Reformation and the rise of religious toleration in Europe.
“Buddhism for Chinese Readers”: Zhi Qian’s Literary Refinements in the Foshuo pusa benye jing
Authors: Han Jaehee , Hwang Soonil , Lee Hyebin
Published: May 2021

The present article continues the modern scholarship on the transmission of Buddhism from India to China by focusing on one of the most influential figures among the early Chinese Buddhist translators, namely, Zhi Qian (支謙, ca. 193–252 CE). His translation style is characterized as “kaleidoscopic,” as Jan Nattier describes, due to the high degree of diversity and variability in his language and terminology. In this study, we explore Zhi Qian’s literary refinements from the lexical, stylistic, and conceptual points of view based on his Foshuo pusa benye jing (佛說菩薩本業經, T. 281) in close conjunction with three related sūtras, the Foshuo dousha jing (佛説兜沙經, T. 280), the Zhu pusa qiufo benye jing (諸菩薩求佛本業經, T. 282), and the Pusa shizhu xingdao pin (菩薩十住行道品, T. 283), all attributed to Lokakṣema. We specifically discuss how Zhi Qian produced such a polished and “sinicised” version with various modes of literary modifications (e.g., using wenyan elements, four-syllable prosodic pattern, diverse vocabulary, and indigenous Chinese concepts) within the context of his life and times. In this article, we also argue that his main aim in producing the Foshuo pusa benye jing was to provide a more classical, elegant, and readable Buddhist scripture to the Chinese readers, but that he had to sacrifice being able to faithfully reflect the language used in the original Indic texts.
Design of PEIS: A Low-Cost Pipe Inspector Robot
Authors: Salvatore Mario , Galloro Alessio , Muzzi Leonardo , Pullano Giovanni , Odry Péter , Carbone Giuseppe
Published: May 2021

This paper outlines the design of a novel mechatronic system for semi-automatic inspection and white-water in-pipe obstruction removals without the need for destructive methods or specialized manpower. The device is characterized by a lightweight structure and high transportability. It is composed by a front, a rear and a central module that realize the worm-like locomotion of the robot with a specifically designed driving mechanism for the straight motion of the robot along the pipeline. The proposed mechatronic system is easily adaptable to pipes of various sizes. Each module is equipped with a motor that actuates three slider-crank-based mechanisms. The central module incorporates a length-varying mechanism that allows forward and backward locomotion. The device is equipped with specific low-cost sensors that allow an operator to monitor the device and locate an obstruction in real time. The movement of the device can be automatic or controlled manually by using a specific user-friendly control board and a laptop. Preliminary laboratory tests are reported to demonstrate the engineering feasibility and effectiveness of the proposed design, which is currently under patenting.
Towards a Fully Automated 3D Reconstruction System Based on LiDAR and GNSS in Challenging Scenarios
Authors: Ren Ruike , Fu Hao , Xue Hanzhang , Sun Zhenping , Ding Kai , Wang Pengji
Published: May 2021

High-precision 3D maps play an important role in autonomous driving. The current mapping system performs well in most circumstances. However, it still encounters difficulties in the case of the Global Navigation Satellite System (GNSS) signal blockage, when surrounded by too many moving objects, or when mapping a featureless environment. In these challenging scenarios, either the global navigation approach or the local navigation approach will degenerate. With the aim of developing a degeneracy-aware robust mapping system, this paper analyzes the possible degeneration states for different navigation sources and proposes a new degeneration indicator for the point cloud registration algorithm. The proposed degeneracy indicator could then be seamlessly integrated into the factor graph-based mapping framework. Extensive experiments on real-world datasets demonstrate that the proposed 3D reconstruction system based on GNSS and Light Detection and Ranging (LiDAR) sensors can map challenging scenarios with high precision.
Remote Sensing Based Spatial-Temporal Monitoring of the Changes in Coastline Mangrove Forests in China over the Last 40 Years
Authors: Zhang Junyao , Yang Xiaomei , Wang Zhihua , Zhang Tao , Liu Xiaoliang
Published: May 2021

As a developing country, China’s mangrove landscape pattern has undergone significant temporal and spatial changes over the last four decades. However, we know little about the changes in the mangrove landscape pattern characteristics other than the area at the national scale. The analysis of mangrove landscape pattern changes from different perspectives on a national scale can provide scientific support for mangrove protection and restoration. In this study, the temporal and spatial changes in the pattern of the mangrove landscape over the last 40 years in China were analyzed based on remote sensing data with high classification accuracy (99.3% of 2018). First, according to the natural geographical conditions of the coastal zone and the distribution of the mangroves, the distribution area of the mangroves in China was divided into 31 natural shores. Then, by selecting representative landscape indexes and constructing an integrated landscape index, the spatial-temporal changes in the landscape pattern of China’s mangroves over the last 40 years were analyzed based on five perspectives: Total area change, shape complexity, connectivity, fragmentation, and the integrated state of the landscape. From a temporal viewpoint, before 2000, the total area of each shore exhibited a downward trend, and the degree of connectivity deteriorated continuously, but the degree of fragmentation was stable at a low level. After 2000, although the total area improved, the degree of fragmentation gradually increased. The spatial changes are mainly reflected by the fact that the shores in Guangdong and Hainan exhibited significant differences within the same province. Based on the above analysis, corresponding scientific suggestions are proposed from temporal and spatial viewpoints to provide guidance for mangrove management and protection in China and to provide a reference for mangrove research in other regions of the world.
Detection of Root-Knot Nematode Meloidogyne luci Infestation of Potato Tubers Using Hyperspectral Remote Sensing and Real-Time PCR Molecular Methods
Authors: Žibrat Uroš , Gerič Stare Barbara , Knapič Matej , Susič Nik , Lapajne Janez , Širca Saša
Published: May 2021

Root-knot nematodes (Meloidogyne spp.) are considered the most aggressive, damaging, and economically important group of plant-parasitic nematodes and represent a significant limiting factor for potato (Solanum tuberosum) production and tuber quality. Meloidogyne luci has previously been shown to be a potato pest having significant reproductive potential on the potato. In this study we showed that M. luci may develop a latent infestation without visible symptoms on the tubers. This latent infestation may pose a high risk for uncontrolled spread of the pest, especially via seed potato. We developed efficient detection methods to prevent uncontrolled spread of M. luci via infested potato tubers. Using hyperspectral imaging and a molecular approach to detection of nematode DNA with real-time PCR, it was possible to detect M. luci in both heavily infested potato tubers and tubers without visible symptoms. Detection of infested tubers with hyperspectral imaging achieved a 100% success rate, regardless of tuber preparation. The real-time PCR approach detected M. luci with high sensitivity.
Combining Satellite InSAR, Slope Units and Finite Element Modeling for Stability Analysis in Mining Waste Disposal Areas
Authors: López-Vinielles Juan , Fernández-Merodo José A. , Ezquerro Pablo , García-Davalillo Juan C. , Sarro Roberto , Reyes-Carmona Cristina , Barra Anna , Navarro José A. , Krishnakumar Vrinda , Alvioli Massimiliano , Herrera Gerardo
Published: May 2021

Slope failures pose a substantial threat to mining activity due to their destructive potential and high probability of occurrence on steep slopes close to limit equilibrium conditions, which are often found both in open pits and in waste and tailing disposal facilities. The development of slope monitoring and modeling programs usually entails the exploitation of in situ and remote sensing data, together with the application of numerical modeling, and it plays an important role in the definition of prevention and mitigation measures aimed at minimizing the impact of slope failures in mining areas. In this paper, a new methodology is presented; one that combines satellite radar interferometry and 2D finite element modeling for slope stability analysis at a regional scale, and applied within slope unit polygons. Although the literature includes many studies applying radar interferometry and modeling for slope stability analysis, the addition of slope units as input data for radar interferometry and modeling purposes has, to our knowledge, not previously been reported. A former mining area in southeast Spain was studied, and the method proved useful for detecting and characterizing a large number of unstable slopes. Out of the 1959 slope units used for the spatial analysis of the radar interferometry data, 43 were unstable, with varying values of safety factor and landslide size. Out of the 43 active slope units, 21 exhibited line of sight velocities greater than the maximum error obtained through validation analysis (2.5 cm/year). Finally, this work discusses the possibility of using the results of the proposed approach to devise a proxy for landslide hazard. The proposed methodology can help to provide non-expert final users with intelligible, clear, and easily comparable information to analyze slope instabilities in different settings, and not limited to mining areas.
Feature-Aided RTK/LiDAR/INS Integrated Positioning System with Parallel Filters in the Ambiguity-Position-Joint Domain for Urban Environments
Authors: Li Wenyi , Liu Gang , Cui Xiaowei , Lu Mingquan
Published: May 2021

As the modern navigation business evolves, demands for high-precision positioning in GNSS-challenged environments increase, and the integrated system composed of Global Navigation Satellite System (GNSS)-based Real-Time Kinematic (RTK), inertial system (INS), Light Detection and Ranging (LiDAR), etc., is accepted as the most feasible solution to the issue. For prior-map-free situations, as the only sensor with a global frame, RTK determines and maintains the global positioning precision of the integrated system. However, RTK performance degrades greatly in GNSS-challenged environments, and most of the existing integrated systems adopt loose coupling mode, which does nothing to improve RTK and, thus, prevents integrated systems from further improvement. Aiming at improving RTK performance in the RTK/LiDAR/INS integrated system, we proposed an innovative integrated algorithm that utilizes RTK to register LiDAR features while integrating the pre-registered LiDAR features to RTK and adopts parallel filters in the ambiguity-position-joint domain to weaken the effects of low satellite availability, cycle slips, and multipath. By doing so, we can improve the RTK fix rate and stability in GNSS-challenged environments. The results of the theoretical analyses, simulation experiments, and a road test proved that the proposed method improved RTK performance in GNSS-challenged environments and, thus, guaranteed the global positioning precision of the whole system.
Spherically Optimized RANSAC Aided by an IMU for Fisheye Image Matching
Authors: Liang Anbang , Li Qingquan , Chen Zhipeng , Zhang Dejin , Zhu Jiasong , Yu Jianwei , Fang Xu
Published: May 2021

Fisheye cameras are widely used in visual localization due to the advantage of the wide field of view. However, the severe distortion in fisheye images lead to feature matching difficulties. This paper proposes an IMU-assisted fisheye image matching method called spherically optimized random sample consensus (So-RANSAC). We converted the putative correspondences into fisheye spherical coordinates and then used an inertial measurement unit (IMU) to provide relative rotation angles to assist fisheye image epipolar constraints and improve the accuracy of pose estimation and mismatch removal. To verify the performance of So-RANSAC, experiments were performed on fisheye images of urban drainage pipes and public data sets. The experimental results showed that So-RANSAC can effectively improve the mismatch removal accuracy, and its performance was superior to the commonly used fisheye image matching methods in various experimental scenarios.
New Concept for the Study of the Fluid Dynamics of Lithium Extraction Using Calix[4]arene Derivatives in T-Type Microreactor Systems
Authors: Kurniawan Yehezkiel , Sathuluri Ramachandra , Ohto Keisuke , Iwasaki Wataru , Kawakita Hidetaka , Morisada Shintaro , Miyazaki Masaya , Jumina Jumina
Published: May 2021

Lithium extraction remains a challenge in the hydrometallurgy process due to its economic value and maldistribution sources. Employing calix[4]arene derivatives in solvent extraction techniques results in high selectivity and extraction capability, but a slow extraction rate. The slow kinetics of batch-wise extraction can be drastically accelerated by using a T-type microreactor system. Therefore, a combination of calix[4]arene and a microreactor system serves as an ideal platform for efficient lithium extraction. In this work, the fluid dynamics of lithium extraction using a monoacetic acid calix[4]arene derivative in a T-type microreactor system were studied. Increasing the O/A ratio increases the average length, surface area, and volume of the organic droplets, but decreases the specific surface area. In contrast, increasing the Reynolds number decreases the average length, surface area, and volume of the organic droplets, but increases the specific surface area. It was found that shorter diffusion distance, larger specific surface area, and faster vortex velocity were the factors that play the most pivotal roles in achieving great extraction rate enhancement in T-type microreactor systems compared to batch-wise systems. These findings represent an important new concept in the study of the fluid dynamics of lithium extraction using monoacetic acid calix[4]arene derivatives in T-type microreactor systems.
Disaster Management in Smart Cities
Authors: Elvas Luís B. , Mataloto Bruno Miguel , Martins Ana Lúcia , Ferreira João C.
Published: May 2021

The smart city concept, in which data from different systems are available, contains a multitude of critical infrastructures. This data availability opens new research opportunities in the study of the interdependency between those critical infrastructures and cascading effects solutions and focuses on the smart city as a network of critical infrastructures. This paper proposes an integrated resilience system linking interconnected critical infrastructures in a smart city to improve disaster resilience. A data-driven approach is considered, using artificial intelligence and methods to minimize cascading effects and the destruction of failing critical infrastructures and their components (at a city level). The proposed approach allows rapid recovery of infrastructures’ service performance levels after disasters while keeping the coverage of the assessment of risks, prevention, detection, response, and mitigation of consequences. The proposed approach has the originality and the practical implication of providing a decision support system that handles the infrastructures that will support the city disaster management system—make the city prepare, adapt, absorb, respond, and recover from disasters by taking advantage of the interconnections between its various critical infrastructures to increase the overall resilience capacity. The city of Lisbon (Portugal) is used as a case to show the practical application of the approach.
Study on the Influencing Factors and Acting Path of the Sustainable Development of Rural Tourism Based on EEAM-ISM Model
Authors: Weng Gangmin , Pan Yue , Li Jianpu
Published: May 2021

The sustainable development of rural tourism is a complex system that includes both objective environmental factors and subjective human factors. Based on the three dimensions of “man–machine–environment”, the element event analysis method (EEAM) is introduced to identify and determine the components of the rural tourism composite system. Then, a hierarchical digraph of the rural tourism complex system is constructed by the interpretative structural model (ISM), and the logical structural relations among factors are explored to clarify the action paths. It is found that: (1) through three rounds of soliciting opinions and revising the list of factors, a total of 26 key factors affecting the sustainable development of rural tourism were screened out; (2) the influencing factors are related to each other to form a five-level factor hierarchical structure, which clearly reveals the overall structure of the system and the support dependencies among factors; (3) on the basis of clarifying the path of influencing factors, the targeted countermeasures and suggestions for the sustainable development of rural tourism are proposed for three key paths. This not only provides a certain theoretical basis for sustainable forecasting but also helps decision-makers to take targeted countermeasures.
Airflow Characteristics According to the Change in the Height and Porous Rate of Building Roofs for Efficient Installation of Small Wind Power Generators
Authors: You Jangyoul , You Kipyo , Park Minwoo , Lee Changhee
Published: May 2021

In this paper, the air flow characteristics and the impact of wind power generators were analyzed according to the porosity and height of the parapet installed in the rooftop layer. The wind speed at the top was decreasing as the parapet was installed. However, the wind speed reduction effect was decreasing as the porosity rate increased. In addition, the increase in porosity significantly reduced turbulence intensity and reduced it by up to 40% compared to no railing. In the case of parapets with sufficient porosity, the effect of reducing turbulence intensity was also increased as the height increased. Therefore, it was confirmed that sufficient parapet height and high porosity reduce the effect of reducing wind speed by parapets and significantly reducing the turbulence intensity, which can provide homogeneous wind speed during installation of wind power generators.
Reliability Evaluation of Smart Microgrids Considering Cyber Failures and Disturbances under Various Cyber Network Topologies and Distributed Generation’s Scenarios
Authors: Aslani Mehrdad , Hashemi-Dezaki Hamed , Ketabi Abbas
Published: May 2021

Smart microgrids (SMGs), as cyber–physical systems, are essential parts of smart grids. The SMGs’ cyber networks facilitate efficient system operation. However, cyber failures and interferences might adversely affect the SMGs. The available studies about SMGs have paid less attention to SMGs’ cyber–physical features compared to other subjects. Although a few current research works have studied the cyber impacts on SMGs’ reliability, there is a research gap about reliability evaluation simultaneously concerning all cyber failures and interferences under various cyber network topologies and renewable distributions scenarios. This article aims to fill such a gap by developing a new Monte Carlo simulation-based reliability assessment method considering cyber elements’ failures, data/information transmission errors, and routing errors under various cyber network topologies. Considering the microgrid control center (MGCC) faults in comparion to other failures and interferences is one of the major contributions of this study. The reliability evaluation of SMGs under various cyber network topologies, particularly based on an MGCC’s redundancy, highlights this research’s advantages. Moreover, studying the interactions of uncertainties for cyber systems and distributed generations (DGs) under various DG scenarios is another contribution. The proposed method is applied to a test system using actual historical data. The comparative test results illustrate the advantages of the proposed method.
Ranking Environmental Aspects of Sustainable Tourism: Case of Selected European Countries
Authors: Škrinjarić Tihana
Published: May 2021

The tourism industry is one of the fastest-growing industries today, and it is important to obtain insights into its good and bad practices. This will provide policymakers with as much information as possible to tailor specific policies to facilitate tourism and economic growth. The main purpose of this paper is a critical overview of the related research on the topic of evaluating sustainable tourism in European countries and extensive empirical research on achieving sustainable tourism. This research includes Grey Systems Theory (GST) as the main tool in evaluating the efficiency of sustainable tourism. Robustness checking is done via the multiple criteria decision making (MCDM) approach. Although the literature on tourism efficiency is vast, there is a smaller amount of research related to the approach taken in this paper. Thus, a comprehensive and insightful analysis will be done so that relevant and timely information can be obtained for the future decision-making process. Furthermore, a dynamic analysis will be provided so that changes in time can be observed and a detailed analysis can be made.
Towards Sustainable Digital Innovation of SMEs from the Developing Countries in the Context of the Digital Economy and Frugal Environment
Authors: Yousaf Zahid , Radulescu Magdalena , Sinisi Crenguta Ileana , Serbanescu Luminita , Păunescu Loredana Maria
Published: May 2021

This study aims to explore the direct impact of the digital orientation, Internet of Things (IoT) and digital platforms on the sustainable digital innovation in the context of the digital economy and frugal environment. This study also investigated the mediating role of the digital platforms in these relations. The study was based on the quantitative research design and data were collected from the 397 CEOs and managing directors of Small and Medium Enterprises in Pakistan. Correlation and structural equation modeling approaches were applied for the analysis and testing of the hypotheses. Results revealed that the digital orientation, IoT and digital platform are major antecedents of the sustainable digital innovation. Results also show that the digital platforms mediate between both digital orientation-sustainable digital innovation link and IoT-sustainable digital innovation link. The rapid pace of change in the technology has forced the business organizations to think out of box and align their operational mechanism accordingly. The need for the sustainable digital innovation is a major need of the current decade for meeting the increasing demands of the society in a sustainable way. Organizations, especially SMEs, should be able to deal with these challenges and rapid technological transformations through cost effective frugal business models. The frugal innovation is an important element of sustainable digital innovation enables SMEs to reduce resources usage and waste and to enhance sustainable economic activities. In this way, they can develop and gain advantages in this highly competitive digital environment. This is the first study showing the bright harmony of the digital orientation, IoT and digital platforms for achieving the sustainable digital innovation in the rapid evolving digital economy.
Hydrogen vs. Battery-Based Propulsion Systems in Unipersonal Vehicles—Developing Solutions to Improve the Sustainability of Urban Mobility
Authors: Isorna Llerena F. , López González E. , Caparrós Mancera J. J. , Segura Manzano F. , Andújar J. M.
Published: May 2021

The percentage of the population in urban areas has increased by ten points from 2000 (46%) to 2020 (56%); it is expected to reach up to 70% by 2050. This undoubtedly will encourage society to use alternative transports. On the other hand, the widespread fear of pandemics seems to be here to stay, and it is causing most people to leave public transport to use private cars, and a few have chosen unipersonal electric vehicles. As a consequence, the decision of using private cars negatively affects the air quality, and consequently urban population health. This paper aims to demonstrate a sustainable solution for urban mobility based on a hydrogen powered unipersonal electric vehicle, which, as shown, provides great advantages over the conventional battery powered unipersonal electric vehicle. To show this, the authors have developed both vehicles in comparable versions, using the same platform, and ensuring that the total weight of the unipersonal electric vehicle was the same in both cases. They have been subjected to experimental tests that support the features of the hydrogen-based configuration versus the battery-based one, including higher specific energy, more autonomy, and shorter recharge time.
Developing a Participatory Planning Support System for Sustainable Regional Planning—A Problem Structuring Case Study
Authors: Aspen Dina Margrethe , Amundsen Andreas
Published: May 2021

In this paper, we report on the application of systems engineering in initiating the synthesis of a participatory planning support system (PSS) for sustainable regional planning. The systems engineering SPADE approach is applied in a model-based fashion to define and link sustainable development goals (SDGs) to regional and urban planning policies in a co-creative multi-stakeholder environment. The approach is demonstrated through a case study from the interregional climate, land-use, and transportation planning process (PAKT) in the Ålesund region in Norway. The work was performed using focus groups with planning stakeholders over a series of workshops to analyze, design, verify and validate the problem structure. Our study shows that the approach is useful for integrating and operationalizing the SDGs in a planning context. The methodology also brings clarity and structure to planning problems and provides a pedagogical frame to engage stakeholders in co-creative PSS synthesis. Further research is necessary to explore how structured elements may be exploited in PSS synthesis.
On the Optimal Tilt Angle and Orientation of an On-Site Solar Photovoltaic Energy Generation System for Sabah’s Rural Electrification
Authors: Matius Maryon Eliza , Ismail Mohd Azlan , Farm Yan Yan , Amaludin Adriana Erica , Radzali Mohd Adzrie , Fazlizan Ahmad , Muzammil Wan Khairul
Published: May 2021

An ongoing project to implement a mini standalone solar photovoltaic (PV) generation system of 2.5 kWp capacity at the eco-tourism centre of Liogu Ku Silou-Silou (EPLISSI), Sabah, was initiated in 2019. Since the solar panel support (ground mounting) used in this project will be erected separately, the main goals of this study are to estimate the optimum tilt angle, βopt, and orientation for the solar PV modules. To achieve these goals, the Liu and Jordan isotropic diffuse radiation model was used (1960). Another three isotropic diffuse sky radiation models (Koronakis model, Badescu model, and Tian model) were applied to estimate the optimum tilt angle with the orientation kept facing due south. For verification purposes, the PV power output data obtained from an online PV simulator known as Global Solar Atlas or GSA 2.3 was used and compared to the results of the four isotropic models. The results suggest that the Tian model is more suitable for approximating insolation, as it was proven to have the lowest difference among all models and is in close agreement with the result of the optimum tilt angle provided by GSA 2.3. However, the outcomes demonstrated from the isotropic models propose an error up to 30% (in the range of 31% to 32%) as compared to GSA 2.3.
Axial Stress-Strain Performance of Recycled Aggregate Concrete Reinforced with Macro-Polypropylene Fibres
Authors: Munir Muhammad Junaid , Kazmi Syed Minhaj Saleem , Wu Yu-Fei , Lin Xiaoshan , Ahmad Muhammad Riaz
Published: May 2021

The addition of macro-polypropylene fibres improves the stress-strain performance of natural aggregate concrete (NAC). However, limited studies focus on the stress-strain performance of macro-polypropylene fibre-reinforced recycled aggregate concrete (RAC). Considering the variability of coarse recycled aggregates (CRA), more studies are needed to investigate the stress-strain performance of macro-polypropylene fibre-reinforced RAC. In this study, a new type of 48 mm long BarChip macro-polypropylene fibre with a continuously embossed surface texture is used to produce BarChip fibre-reinforced NAC (BFNAC) and RAC (BFRAC). The stress-strain performance of BFNAC and BFRAC is studied for varying dosages of BarChip fibres. Results show that the increase in energy dissipation capacity (i.e., area under the curve), peak stress, and peak strain of samples is observed with an increase in fibre dosage, indicating the positive effect of fibre addition on the stress-strain performance of concrete. The strength enhancement due to the addition of fibres is higher for BFRAC samples than BFNAC samples. The reduction in peak stress, ultimate strain, toughness and specific toughness of concrete samples due to the utilisation of CRA also reduces with the addition of fibres. Hence, the negative effect of CRA on the properties of concrete samples can be minimised by adding BarChip macro-polypropylene fibres. The applicability of the stress-strain model previously developed for macro-synthetic and steel fibre-reinforced NAC and RAC to BFNAC and BFRAC is also examined.
Is Motivation Associated with Mental Fatigue during Padel Trainings? A Pilot Study
Authors: Díaz-García Jesús , López-Gajardo Miguel Ángel , Ponce-Bordón José Carlos , Pulido Juan José
Published: May 2021

Motivation seems to enhance athletes’ mental efforts, but this has not been tested yet in padel. The objective was to test the effects of motivation on mental fatigue during padel trainings. Thirty-six elite youth players participated (twenty-two males, Mage = 17.40, SDage = 2.16, and fourteen females, Mage = 17.90, SDage = 3.21). We designed four padel training matches, introducing a constraint in two of them in a counterbalanced order. The constraint was: Couples that win more sets in these two matches obtain a free lesson with a professional padel player. Motivation was quantified by a questionnaire before the matches. Moreover, subjective feelings of mental load and fatigue were measured with questionnaires, and objective measures of fatigue were quantified through heart-rate variability and reaction time. Results suggest that the constraint significantly increases motivation (p < 0.001). Furthermore, in these matches, players reported significantly higher feelings and objective measures of fatigue (p < 0.001 for HRV and VAS; p = 0.04 for reaction time). An increase in the resources used by the neural facilitation system, mediated by higher values of motivation, seems a relevant candidate to explain this phenomenon.
A Simulation on Relation between Power Distribution of Low-Frequency Field Potentials and Conducting Direction of Rhythm Generator Flowing through 3D Asymmetrical Brain Tissue
Authors: Cheng Hao , Ge Manling , Belkacem Abdelkader Nasreddine , Fu Xiaoxuan , Xie Chong , Song Zibo , Chen Shenghua , Chen Chao
Published: May 2021

Although the power of low-frequency oscillatory field potentials (FP) has been extensively applied previously, few studies have investigated the influence of conducting direction of deep-brain rhythm generator on the power distribution of low-frequency oscillatory FPs on the head surface. To address this issue, a simulation was designed based on the principle of electroencephalogram (EEG) generation of equivalent dipole current in deep brain, where a single oscillatory dipole current represented the rhythm generator, the dipole moment for the rhythm generator’s conducting direction (which was orthogonal and rotating every 30 degrees and at pointing to or parallel to the frontal lobe surface) and the (an)isotropic conduction medium for the 3D (a)symmetrical brain tissue. Both the power above average (significant power value, SP value) and its space (SP area) of low-frequency oscillatory FPs were employed to respectively evaluate the strength and the space of the influence. The computation was conducted using the finite element method (FEM) and Hilbert transform. The finding was that either the SP value or the SP area could be reduced or extended, depending on the conducting direction of deep-brain rhythm generator flowing in the (an)isotropic medium, suggesting that the 3D (a)symmetrical brain tissue could decay or strengthen the spatial spread of a rhythm generator conducting in a different direction.
The Superconducting Critical Temperature
Authors: Guidry Mike , Sun Yang , Wu Lian-Ao
Published: May 2021

Two principles govern the critical temperature for superconducting transitions: (1) intrinsic strength of the pair coupling and (2) the effect of the many-body environments on the efficiency of that coupling. Most discussions take into account only the former, but we argue that the properties of unconventional superconductors are governed more often by the latter, through dynamical symmetry relating to normal and superconducting states. Differentiating these effects is essential to charting a path to the highest-temperature superconductors.
Comparison between Single-Phase Flow Simulation and Multiphase Flow Simulation of Patient-Specific Total Cavopulmonary Connection Structures Assisted by a Rotationally Symmetric Blood Pump
Authors: Chen Tong , Liu Xudong , Si Biao , Feng Yong , Zhang Huifeng , Jia Bing , Wang Shengzhang
Published: May 2021

To accurately assess the hemolysis risk of the ventricular assist device, this paper proposed a cell destruction model and the corresponding evaluation parameters based on multiphase flow. The single-phase flow and multiphase flow in two patient-specific total cavopulmonary connection structures assisted by a rotationally symmetric blood pump (pump-TCPC) were simulated. Then, single-phase and multiphase cell destruction models were used to evaluate the hemolysis risk. The results of both cell destruction models indicated that the hemolysis risk in the straight pump-TCPC model was lower than that in the curved pump-TCPC model. However, the average and maximum values of the multiphase flow blood damage index (mBDI) were smaller than those of the single-phase flow blood damage index (BDI), but the average and maximum values of the multiphase flow particle residence time (mPRT) were larger than those of the single-phase flow particle residence time (PRT). This study proved that the multiphase flow method can be used to simulate the mechanical behavior of red blood cells (RBCs) and white blood cells (WBCs) in a complex flow field and the multiphase flow cell destruction model had smaller estimates of the impact shear stress.
Full Factorial Design for Gold Recovery from Industrial Solutions
Authors: Mihăilescu Maria , Negrea Adina , Ciopec Mihaela , Negrea Petru , Duțeanu Narcis , Grozav Ion , Svera Paula , Vancea Cosmin , Bărbulescu Alina , Dumitriu Cristian Ștefan
Published: May 2021

Gold is one of the precious metals with multiple uses, whose deposits are much smaller than the global production needs. Therefore, extracting maximum gold quantities from industrial diluted solutions is a must. Am-L-GA is a new material, obtained by an Amberlite XAD7-type commercial resin, functionalized through saturation with L-glutamic acid, whose adsorption capacity has been proved to be higher than those of other materials utilized for gold adsorption. In this context, this article presents the results of a factorial design experiment for optimizing the gold recovery from residual solutions resulting from the electronics industry using Am-L-GA. Firstly, the material was characterized using atomic force microscopy (AFM), to emphasize the material’s characteristics, essential for the adsorption quality. Then, the study showed that among the parameters taken into account in the analysis (pH, temperature, initial gold concentration, and contact time), the initial gold concentration in the solution plays a determinant role in the removal process and the contact time has a slightly positive effect, whereas the pH and temperature do not influence the adsorption capacity. The maximum adsorption capacity of 29.27 mg/L was obtained by optimizing the adsorption process, with the control factors having the following values: contact time ~106 min, initial Au(III) concentration of ~164 mg/L, pH = 4, and temperature of 25 °C. It is highlighted that the factorial design method is an excellent instrument to determine the effects of different factors influencing the adsorption process. The method can be applied for any adsorption process if it is necessary to reduce the number of experiments, to diminish the resources or time consumption, or for expanding the investigation domain above the experimental limits.
Toxic Effects of Docosahexaenoic Acid Treatment in the Rat Liver BRL-3A Cell
Authors: Luo Wenli , Li Li , Xu Weina , Zhang Jing , Xu Jianxiong
Published: May 2021

The cytotoxicity of docosahexaenoic acid (DHA) on normal cells is still unclear. This study investigated the effects of DHA on the cytotoxicity and possible mechanism in the BRL-3A cell. The cultured rat liver BRL-3A cell line was treated with 50, 100 and 200 μM DHA for 24 h. The cell viability was increased in the 50 and 100 μM DHA treatments, but decreased in the 200 μM DHA treatment. The 50, 100 and 200 μM DHA treatments increased the proportion of the apoptotic cells, the levels of lactate dehydrogenase (LDH), alkaline phosphatase (AKP) and IL-6 in the supernatant, and the ratio of the phosphonated p38MAPK to the p38MAPK (p-p38/p38) protein in the cells. The expression of TGF beta-activated kinase 1 (TAK1), nuclear transcription factor-κB p65 (NF-κB p65) and the inhibitor of NF-κB alpha (IκBα) mRNA, and the ratio of the phosphonated IκBα (p-IκBα) to IκBα protein were increased in the 200 μM DHA treatment, while the ratio of phosphonated extracellular regulated protein kinases (p-ERK) to ERK protein was decreased in the 200 μM DHA treatment. These results indicate that DHA-treated (50, 100 and 200 μM) BRL-3A cells for 24 h promotes cell apoptosis and inflammatory response, and the p38 MAPK, ERK and NF-κB signal pathways were involved in mediating the apoptosis and inflammatory response.
Synergistic Effects of Zinc Oxide Nanoparticles and Bacteria Reduce Heavy Metals Toxicity in Rice (Oryza sativa L.) Plant
Authors: Akhtar Nazneen , Khan Sehresh , Rehman Shafiq Ur , Rehman Zia Ur , Khatoon Amana , Rha Eui Shik , Jamil Muhammad
Published: May 2021

Heavy metals (HMs) are toxic elements which contaminate the water bodies in developing countries because of their excessive discharge from industrial zones. Rice (Oryza sativa L) crops are submerged for a longer period of time in water, so irrigation with HMs polluted water possesses toxic effects on plant growth. This study was initiated to observe the synergistic effect of bacteria (Bacillus cereus and Lysinibacillus macroides) and zinc oxide nanoparticles (ZnO NPs) (5, 10, 15, 20 and 25 mg/L) on the rice that were grown in HMs contaminated water. Current findings have revealed that bacteria, along with ZnO NPs at lower concentration, showed maximum removal of HMs from polluted water at pH 8 (90 min) as compared with higher concentrations. Seeds primed with bacteria grown in HM polluted water containing ZnO NPs (5 mg/L) showed reduced uptake of HMs in root, shoot and leaf, thus resulting in increased plant growth. Furthermore, their combined effects also reduced the bioaccumulation index and metallothionine (MTs) content and enhanced the tolerance index of plants. This study suggested that synergistic treatment of bacteria with lower concentrations of ZnO NPs helped plants to reduce heavy metal toxicity, especially Pb and Cu, and enhanced plant growth.
Assessing the Impact of COVID-19 on TB and HIV Programme Services in Selected Health Facilities in Lilongwe, Malawi: Operational Research in Real Time
Authors: Thekkur Pruthu , Tweya Hannock , Phiri Sam , Mpunga James , Kalua Thokozani , Kumar Ajay M. V. , Satyanarayana Srinath , Shewade Hemant D. , Khogali Mohammed , Zachariah Rony , Rusen I. D. , Berger Selma Dar , Harries Anthony D.
Published: May 2021

When the COVID-19 pandemic was announced in March 2020, there was concern that TB and HIV programme services in Malawi would be severely affected. We set up real-time monthly surveillance of TB and HIV activities in eight health facilities in Lilongwe to see if it was possible to counteract the anticipated negative impact on TB case detection and treatment and HIV testing. Aggregate data were collected monthly during the COVID-19 period (March 2020–February 2021) using an EpiCollect5 application and compared with monthly data collected during the pre-COVID-19 period (March 2019–February 2020); these reports were sent monthly to programme directors. During COVID-19, there was an overall decrease in persons presenting with presumptive pulmonary TB (45.6%), in patients registered for TB treatment (19.1%), and in individuals tested for HIV (39.0%). For presumptive TB, children and females were more affected, but for HIV testing, adults and males were more affected. During COVID-19, the TB treatment success rate (96.1% in pre-COVID-19 and 96.0% during COVID-19 period) and referral of HIV-positive persons to antiretroviral therapy (100% in pre-COVID-19 and 98.6% during COVID-19 period) remained high and largely unchanged. Declining trends in TB and HIV case detection were not redressed despite real-time monthly surveillance.
National Antimicrobial Consumption: Analysis of Central Warehouses Supplies to In-Patient Care Health Facilities from 2017 to 2019 in Uganda
Authors: Namugambe Juliet Sanyu , Delamou Alexandre , Moses Francis , Ali Engy , Hermans Veerle , Takarinda Kudakwashe , Thekkur Pruthu , Nanyonga Stella Maris , Koroma Zikan , Mwoga Joseph Ngobi , Akello Harriet , Imi Monica , Kitutu Freddy Eric
Published: May 2021

Antimicrobial consumption (AMC) surveillance at global and national levels is necessary to inform relevant interventions and policies. This study analyzed central warehouse antimicrobial supplies to health facilities providing inpatient care in Uganda. We collected data on antimicrobials supplied by National Medical Stores (NMS) and Joint Medical Stores (JMS) to 442 health facilities from 2017 to 2019. Data were analyzed using the World Health Organization methodology for AMC surveillance. Total quantity of antimicrobials in defined daily dose (DDD) were determined, classified into Access, Watch, Reserve (AWaRe) and AMC density was calculated. There was an increase in total DDDs distributed by NMS in 2019 by 4,166,572 DDD. In 2019, Amoxicillin (27%), Cotrimoxazole (20%), and Metronidazole (12%) were the most supplied antimicrobials by NMS while Doxycycline (10%), Amoxicillin (19%), and Metronidazole (10%) were the most supplied by JMS. The majority of antimicrobials supplied by NMS (81%) and JMS (66%) were from the Access category. Increasing antimicrobial consumption density (DDD per 100 patient days) was observed from national referral to lower-level health facilities. Except for NMS in 2019, total antimicrobials supplied by NMS and JMS remained the same from 2017 to 2019. This serves as a baseline for future assessments and monitoring of stewardship interventions.