bluuebunny/crossref_metadata_2025 huggingface dataset:
Weight Pressures and Eating Disorder Symptoms among Adolescent Female Gymnasts of Different Performance Levels in Greece
Authors: Kontele Ioanna , Vassilakou Tonia , Donti Olyvia
Published: February 2022

This study examined the weight pressures within the gymnastics environment and explored associations between these pressures and eating disorder (ED) symptoms in adolescent female gymnasts. One hundred and forty-seven competitive gymnasts and 122 recreational-level gymnasts (11–17 years old) completed the Eating Attitudes Test (EAT-26), the Weight-Pressures in Sport-Females (WPS-F), the Social Desirability Scale (SDS) and provided information on their training. It was found that 16.3% of competitive gymnasts and 7.4% of non-competitive gymnasts scored ≥20 in EAT-26, indicating disordered eating behavior. Competitive gymnasts scored higher than non-competitive in the total score of EAT-26 (p = 0.027), as well as in the total score of WPS-F, the sport and coaches weight pressures sub-scale and the appearance and performance weight pressures sub-scale (p < 0.001). Multiple regression analyses indicated that sport and coaches weight pressures, appearance and performance weight pressures and body mass index accounted for 30.3% of the variance of EAT-26 in competitive gymnasts, while the appearance and performance weight pressures sub-scale accounted for 16.3% of the variance of EAT-26 in non-competitive gymnasts. Sport and coaches weight pressures are associated with ED in competitive gymnasts, while body appearance and performance demands correlate with ED in female gymnasts irrespective of competitive level.
Relationship between the Developmental Coordination Disorder Questionnaire 2007 and the Bruininks-Oseretsky Test of Motor Proficiency Second Edition in Korean Children
Authors: Yoon Deukgeun , Kim Misun , Ji Seokyeon , Choi Dabin , Joung Yoo-Sook , Kim Eun
Published: February 2022

This study investigated the relationship between the Developmental Coordination Disorder Questionnaire 2007 (DCDQ’07) and the Bruininks-Oseretsky Test of Motor Proficiency Second Edition (BOT-2) in Korea. This study also adjusted the cutoff score of the DCDQ’07 based on the BOT-2 for Korean children. A total of 256 children were recruited from communities in Korea. They were divided into two age groups: 8 to 9 years old and 10 to 12 years old. Children performed the BOT-2, and their parents completed the DCDQ’07. The correlation between the DCDQ’07 and the BOT-2 was analyzed. The adjusted DCDQ’07 cutoff score for Korean children was calculated using the BOT-2 as the criterion through a receiver operating characteristic curve. A significant correlation between the DCDQ’07 and the BOT-2 was found, indicating that Korean parents’ perception of children’s motor skills was related to their children’s actual motor proficiency. The adjusted cutoff score of the DCDQ’07 had a sensitivity of 72.7–85.7% and a specificity of 62.5–64.0%. This study demonstrated that children’s motor skills reported by Korean parents on the DCDQ’07 were valid based on a community sample. The adjusted cutoff score of the DCDQ’07 could be used to identify children suspected of having a developmental coordination disorder.
A Review of Racial Disparities in Infant Mortality in the US
Authors: Jang Caleb , Lee Henry
Published: February 2022

Racial disparities in infant mortality have persisted, despite the overall decline in the United States’ overall infant mortality rate (IMR). The overall IMR of the entire United States (5.58 per 1000 live births) population masks significant disparities by race and ethnicity: the non-Hispanic Black population experienced an IMR of 10.8 followed by people from Native Hawaiian or Other Pacific Islander populations at 9.4 and American Indians at 8.2. The non-Hispanic White and Asian populations in the United States have the lowest IMR at 4.6 and 3.6, respectively, as of 2018. A variety of factors that characterize minority populations, including experiences of racial discrimination, low income and education levels, poor residential environments, lack of medical insurance, and treatment at low-quality hospitals, demonstrate strong correlations with high infant mortality rates. Identifying, acknowledging, and addressing these disparities must be performed before engaging in strategies to mitigate them. Social determinants of health play a major role in health disparities, including in infant mortality. The study and implementation of programs to address neighborhood factors, education, healthcare access and quality, economic stability, and other personal and societal contexts will help us work towards a common goal of achieving health equity, regardless of racial/ethnic background.
Water and Wastewater Treatment: Selected Topics
Authors: Barbusiński Krzysztof , Filipek Krzysztof
Published: February 2022

Currently, there is a real need for rapid progress and development in almost all industries and areas of human activity [...]
Ecology and Climate of the Earth—The Same Biogeophysical System
Authors: Pielke Roger A. , Peters Debra P.C. , Niyogi Dev
Published: February 2022

Ecology and the climate provide two perspectives of the same biogeophysical system at all spatiotemporal scales More effectively embracing this congruence is an opportunity to improve scientific understanding and predictions as well as for a more effective policy that integrates both the bottom-up community, business-driven framework, and the popular, top-down impact assessment framework. The objective of this paper is, therefore, to more closely integrate the diverse spectrum of scientists, engineers and policymakers into finding optimal solutions to reduce the risk to environmental and social threats by considering the ecology and climate as an integrated system. Assessments such as performed towards the 2030 Plan for Sustainable Development, with its 17 Sustainable Development Goals and its Goal 13 in particular, can achieve more progress by accounting for the intimate connection of all aspects of the Earth’s biogeophysical system.
Characterization of the Dissolution of Water Microdroplets in Oil
Authors: Gerecsei Tamás , Ungai-Salánki Rita , Saftics András , Derényi Imre , Horvath Robert , Szabó Bálint
Published: February 2022

Water in oil emulsions have a wide range of applications from chemical technology to microfluidics, where the stability of water droplets is of paramount importance. Here, using an accessible and easily reproducible experimental setup we describe and characterize the dissolution of water in oil, which renders nanoliter-sized droplets unstable, resulting in their shrinkage and disappearance in a time scale of hours. This process has applicability in creating miniature reactors for crystallization. We test multiple oils and their combinations with surfactants exhibiting widely different rates of dissolution. We derived simple analytical equations to determine the product of the diffusion coefficient and the relative saturation density of water in oil from the measured dissolution data. By measuring the moisture content of mineral and silicone oils with Karl Fischer titration before and after saturating them with water, we calculated the diffusion coefficient of water in these two oils.
Pigment Coloration Research Published in the Science Citation Index Expanded from 1990 to 2020: A Systematic Review and Bibliometric Analysis
Authors: Islam Mohammad Tajul , Farhan Mohammad Sahariar , Faiza Farzana , Halim A. F. M. Fahad , Sharmin Afsana Al
Published: February 2022

A systematic review and bibliometric study were undertaken utilizing the Science Citation Index Expanded database from 1990 to 2020 to obtain insights into the trajectory of pigment coloration research. The study focused on the publication performance in terms of the yearly production and citations, as well as mainstream journals, categories of the Web of Sciences, leading nations, well-known institutions, and research trends. The survey found that the yearly output of scholarly publications on pigment coloration research climbed gradually throughout the first quarter of the study period and then increased substantially in the latter five years. The present research emphasis and future trends were examined after summarizing the paper title and abstract analyses, author keyword analysis, and the most regularly used keywords derived from words in KeyWords Plus. To expand its reach in numerous application areas, pigment coloration research will continue to focus on improving pigment qualities.
Molecular Docking, Tyrosinase, Collagenase, and Elastase Inhibition Activities of Argan By-Products
Authors: Mechqoq Hicham , Hourfane Sohaib , El Yaagoubi Mohamed , El Hamdaoui Abdallah , da Silva Almeida Jackson Roberto Guedes , Rocha Joao Miguel , El Aouad Noureddine
Published: February 2022

The argan tree (Argania spinosa (L.) Skeels) is one of the most important floristic resources in Morocco. This Moroccan endemic tree is known for its numerous therapeutic and medicinal uses. In addition to some medicinal and cosmetic uses, argan fruit pulp and press cake are traditionally used by the Berber population for heating and feeding livestock. Molecular docking is an in silico approach that predicts the interaction between a ligand and a protein. This approach is mainly used in chemistry and pharmacology of natural products as a prediction tool with the purpose of selecting plant extracts or fractions for in vitro tests. The aim of this research is to study the evaluation of potential tyrosinase, collagenase, and elastase inhibitory activities of argan fruit press-cake and pulp extracts. Extracts were evaluated for their total phenolic content (TPC), and the major polyphenols of both press-cake and pulp extracts were submitted to molecular docking in order to determine the mechanisms of action of these compounds. Obtained results revealed that fruit pulp had the strongest dermocosmetic activities, as well as the highest TPC, with values above 55 mg gallic-acid equivalent per gram of dry matter (mgeq AG/gDM). Moreover, those results were positively correlated with the docking findings, suggesting that the pulp lead compounds have higher affinity with tyrosinase, collagenase, and elastase action sites. The results here presented are very promising and open new perspectives for the exploitation of argan-tree by-products as cosmetic agents towards the development of new anti-aging products.
An Overview of “Insect Biodiversity”
Authors: Sollai Giorgia , Solari Paolo
Published: February 2022

Insects comprise more than half of all described species in the animal kingdom and account for a considerable proportion of all biodiversity on the planet [...]
Acknowledgment to Reviewers of Diagnostics in 2021
Authors:   Diagnostics Editorial Office
Published: February 2022

Rigorous peer-reviews are the basis of high-quality academic publishing [...]
Machine Learning-Based Modeling of Ovarian Response and the Quantitative Evaluation of Comprehensive Impact Features
Authors: Liu Liu , Shen Fujin , Liang Hua , Yang Zhe , Yang Jing , Chen Jiao
Published: February 2022

Appropriate ovarian responses to the controlled ovarian stimulation strategy is the premise for a good outcome of the in vitro fertilization cycle. With the booming of artificial intelligence, machine learning is becoming a popular and promising approach for tailoring a controlled ovarian stimulation strategy. Nowadays, most machine learning-based tailoring strategies aim to generally classify the controlled ovarian stimulation outcome, lacking the capacity to precisely predict the outcome and evaluate the impact features. Based on a clinical cohort composed of 1365 women and two machine learning methods of artificial neural network and supporting vector regression, a regression prediction model of the number of oocytes retrieved is trained, validated, and selected. Given the proposed model, an index called the normalized mean impact value is defined and calculated to reflect the importance of each impact feature. The proposed models can estimate the number of oocytes retrieved with high precision, with the regression coefficient being 0.882% and 89.84% of the instances having the prediction number ≤ 5. Among the impact features, the antral follicle count has the highest importance, followed by the E2 level on the human chorionic gonadotropin day, the age, and the Anti-Müllerian hormone, with their normalized mean impact value > 0.3. Based on the proposed model, the prognostic results for ovarian response can be predicted, which enables scientific clinical decision support for the customized controlled ovarian stimulation strategies for women, and eventually helps yield better in vitro fertilization outcomes.
Leaching of Different Clear Aligner Systems: An In Vitro Study
Authors: Alhendi Aseel , Khounganian Rita , Almudhi Abdullazez , Ahamad Syed Rizwan
Published: February 2022

The aim of this study was to investigate and compare the leaching of four different clear aligner systems (Invisalign®, Eon®, SureSmile®, and Clarity®). Three sets of aligners as obtained from the four manufacturers were cut and immersed in glass vials containing ethanol with different solutions. The first was 100% ethanol, the second was 75% ethanol to 25% water, the third was 50% ethanol to water, the fourth was 25% ethanol to 75% water, and the last was 100% water. The samples were incubated for two weeks at 37 °C. Leached substances were detected by the gas chromatography–mass spectrometry (GC-MS). Eleven different chemical compounds were detected and confirmed. Benzene1,3-bis(1,1-dimethylethyl) was the only compound detected in all four systems at levels of 100% and 75% ethanol. Statistically, insignificant differences were detected among the different systems where leaching was confirmed. Eon® system was the only material to show statistically significant differences when comparing the number of leached substances among the immersion solution concentrations. The four included systems showed variable degrees of leaching. The lowest amount of leached chemicals was observed in relation to the Invisalign® system, while the highest number was found in the Eon® system. None of the included clear aligner systems leached detectable amounts of bisphenol-A (BPA).
Boosting C Sequestration and Land Restoration through Forest Management in Tropical Ecosystems: A Mini-Review
Authors: Koutika Lydie-Stella
Published: February 2022

Soil has a major role in sequestering atmospheric CO2. This has further benefits and potential to improve soil fertility and food production, mitigate climate change, restore land degradation, and conserve ecosystem biodiversity. However, its health is increasingly being threatened by the growing population, land degradation and climate change effects. Despite its importance, soil organic carbon (SOC) is understudied in the tropics. This paper reviews how managing forests in tropical ecosystems can benefit SOC sequestration and land restoration. Sequestered SOC has the potential to improve soil fertility, as well as to reduce both land degradation and atmospheric CO2 emissions. It further improves soil structure, aggregation and water infiltration, enhances soil faunal activity and boosts nutrient cycling (C, N, P and S). Managing forest ecosystems is crucial to boost C sequestration, mitigate climate change and restore degraded lands, besides other ecosystem services they provide. Apart from managing natural forests and planted forests, afforesting, reforesting marginal or degraded lands especially when associated with specific practices (organic residue management, introducing nitrogen-fixing species) boost C storage (in both soil and biomass) and foster co-benefits as soil health improvement, food production, land restoration and mitigation of climate change. Improved soil health as a result of sequestered C is confirmed by enhanced physical, biological and chemical soil fertility (e.g., sequestered C stability through its link to N and P cycling driven by soil biota) which foster and sustain soil health.
Cognitive Training in the Domain of Mathematics for Potentially Gifted Children in Primary School
Authors: de Vreeze-Westgeest Mirjam G. J. , Vogelaar Bart
Published: February 2022

This study examined auditive and visual working memory and metacognitive knowledge in 92 gifted children (aged between eight and twelve), utilising a pre-test-training-post-test design, known as the cognitive training design. This approach was used to examine the working memory and metacognitive knowledge of gifted children concerning the progression after a cognitive training programme in arithmetical problem solving, taking into account the role of intelligence. Children were allocated to one of two experimental conditions: children received training after the pre-test (cognitive training condition) or were provided with training after the post-test (control condition). The results show that all children made significant improvements in working memory and metacognition. Intelligence significantly predicted verbal and visual working memory. However, we did not find a meaningful relationship between intelligence and metacognitive knowledge. The cognitive training in arithmetical problem solving seems to bring additional measurable changes in metacognitive knowledge, but not in working memory.
Internet News User Analysis Using Deep Learning and Similarity Comparison
Authors: Choi Sunoh
Published: February 2022

Nowadays, many Korean users read news from portal sites like Naver and Daum. Users can comment on news articles on such sites, and some try to influence public opinion through their comments. Therefore, news users need to be analyzed. This study proposes a deep learning method to classify each user’s political stance. Further, a method is developed to evaluate how many similar comments each user writes, and another method is developed to evaluate the similarity of a user’s comments with other users’ comments. We collect approximately 2.68 million comments from hundreds of thousands of political news articles in April 2017. First, for the top 100 news users, we classify each user’s political stance with 92.3% accuracy by using only 20% of data for deep learning training. Second, an evaluation of how many similar comments each user writes reveals that six users score more than 80 points. Third, an evaluation of the similarity of each user’s comments to other users’ comments reveals that 10 users score more than 80 points. Thus, based on this study, it is possible to detect malicious commenters, thereby enhancing comment systems used in news portal websites.
Reliable and Low-Power Communications System Based on IR-UWB for Offshore Wind Turbines
Authors: Guisasola Aitor , Cortés Ainhoa , Cejudo Javier , da Silva Astrid , Losada Markos , Bustamante Paul
Published: February 2022

In this paper, we propose the design of a low-power wireless sensor network architecture that enables robust communications inside offshore wind turbines. This research work is in the scope of the WATEREYE EU Project, where we have designed a corrosion monitoring solution to work unattended. The architecture is composed of several fixed sensor nodes, one mobile sensor node, several anchors and the WATEREYE Computer (WEC). Our approach is based on Impulse Radio Ultra wideband (IR-UWB) technology offering reliable and low-power communications in these harsh environments. On top of that, we propose a double star network using two UWB channels for the following purposes: one network for communications to send the sensor data and another one for ranging estimations to calculate the indoor positioning of the mobile sensor node. The power strategies applied to our system, at Hardware (HW) and Firmware (FW) levels, are described in detail. Furthermore, we present power consumption measurements obtaining the power profiles and the autonomy of the most important components of the proposed architecture supplied by battery. On the other hand, we describe the methodology to analyze the range, reliability and continuity of the two UWB links providing the packet loss and gaps as a function of distance. The proposed communications system has been validated in three different scenarios considering two of them very hostile environments. Furthermore, one of the scenarios is a real offshore wind turbine.
On-Device Training of Machine Learning Models on Microcontrollers with Federated Learning
Authors: Llisterri Giménez Nil , Monfort Grau Marc , Pueyo Centelles Roger , Freitag Felix
Published: February 2022

Recent progress in machine learning frameworks has made it possible to now perform inference with models using cheap, tiny microcontrollers. Training of machine learning models for these tiny devices, however, is typically done separately on powerful computers. This way, the training process has abundant CPU and memory resources to process large stored datasets. In this work, we explore a different approach: training the machine learning model directly on the microcontroller and extending the training process with federated learning. We implement this approach for a keyword spotting task. We conduct experiments with real devices to characterize the learning behavior and resource consumption for different hyperparameters and federated learning configurations. We observed that in the case of training locally with fewer data, more frequent federated learning rounds more quickly reduced the training loss but involved a cost of higher bandwidth usage and longer training time. Our results indicate that, depending on the specific application, there is a need to determine the trade-off between the requirements and the resource usage of the system.
A Hybrid and Hierarchical Approach for Spatial Exploration in Dynamic Environments
Authors: Zhang Qi , Song Yukai , Jiao Peng , Hu Yue
Published: February 2022

Exploration in unknown dynamic environments is a challenging problem in an AI system, and current techniques tend to produce irrational exploratory behaviours and fail in obstacle avoidance. To this end, we present a three-tiered hierarchical and modular spatial exploration model that combines the intrinsic motivation integrated deep reinforcement learning (DRL) and rule-based real-time obstacle avoidance approach. We address the spatial exploration problem in two levels on the whole. On the higher level, a DRL based global module learns to determine a distant but easily reachable target that maximizes the current exploration progress. On the lower level, another two-level hierarchical movement controller is used to produce locally smooth and safe movements between targets based on the information of known areas and free space assumption. Experimental results on diverse and challenging 2D dynamic maps show that the proposed model achieves almost 90% coverage and generates smoother trajectories compared with a state-of-the-art IM based DRL and some other heuristic methods on the basis of avoiding obstacles in real time.
Towards the Prioritised Use of Transportation Infrastructures: The Case of Vehicle-Specific Dynamic Access Restrictions in City Centres
Authors: Billhardt Holger , Fernández Alberto , Martí Pasqual , Prieto Tejedor Javier , Ossowski Sascha
Published: February 2022

One of the main problems that local authorities of large cities have to face is the regulation of urban mobility. They need to provide the means to allow for the efficient movement of people and distribution of goods. However, the provisioning of transportation services needs to take into account general global objectives, like reducing emissions and having more healthy living environments, which may not always be aligned with individual interests. Urban mobility is usually provided through a transport infrastructure that includes all the elements that support mobility. On many occasions, the capacity of the elements of this infrastructure is lower than the actual demand and thus different transportation activities compete for their use. In this paper, we argue that scarce transport infrastructure elements should be assigned dynamically and in a prioritised manner to transport activities that have a higher utility from the point of view of society; for example, activities that produce less pollution and provide more value to society. In this paper, we define a general model for prioritizing the use of a particular type of transportation infrastructure element called time-unlimited elements, whose usage time is unknown a priori, and illustrate its dynamics through two use cases: vehicle-specific dynamic access restriction in city centres (i) based on the usage levels of available parking spaces and (ii) to assure sustained admissible air quality levels in the city centre. We carry out several experiments using the SUMO traffic simulation tool to evaluate our proposal.
Noise Immunity-Enhanced Capacitance Readout Circuit for Human Interaction Detection in Human Body Communication Systems
Authors: Choi Seong-Wook , Seong Kiho , Lee Sukho , Baek Kwang-Hyun , Shim Yong
Published: February 2022

Recent healthcare systems based on human body communication (HBC) require human interaction sensors. Due to the conductive properties of the human body, capacitive sensors are most widely known and are applied to many electronic gadgets for communication. Capacitance fluctuations due to the fact of human interaction are typically converted to voltage levels using some analog circuits, and then analog-to-digital converters (ADCs) are used to convert analog voltages into digital codes for further processing. However, signals detected by human touch naturally contain large noise, and an active analog filter that consumes a lot of power is required. In addition, the inclusion of ADCs causes the system to use a large area and amount of power. The proposed structure adopts a digital-based moving average filter (MAF) that can effectively operate as a low-pass filter (LPF) instead of a large-area and high-power consumption analog filter. In addition, the proposed ∆C detection algorithm can distinguish between human interaction and object interaction. As a result, two individual digital signals of touch/release and movement can be generated, and the type and strength of the touch can be effectively expressed without the help of an ADC. The prototype chip of the proposed capacitive sensing circuit was fabricated with commercial 65 nm CMOS process technology, and its functionality was fully verified through testing and measurement. The prototype core occupies an active area of 0.0067 mm2, consumes 7.5 uW of power, and has a conversion time of 105 ms.
Multi-Carrier Signal Recognition Method Based on Multi-Feature Input and Hybrid Training Neural Network
Authors: Li Shanshan , Cui Yi , Zhang Qi , Li Zhipei , Gao Ran , Tian Feng , Tian Qinghua , Liu Bingchun , Jiang Jinkun , Wang Yongjun , Xin Xiangjun
Published: February 2022

In order to achieve automatic identification of modulation formats in orthogonal frequency division multiplexing (OFDM) subcarrier signals, a recognition method based on multiple feature inputs and a Hybrid Training Neural Network (HTNN) is proposed, in which an HTNN structure is designed to obtain high-order statistical correlation features and constellations of OFDM subcarriers. The recognition performance of the proposed method in free space channel transmission and atmospheric time-varying channel transmission is studied by simulation. Simulation results show that the overall identification accuracy of the recognition model based on the proposed method exceeded 93.37% in the wide Signal-to-Noise Ratio (SNR) range of the free space channel. With an SNR higher than 7.5 dB, identification accuracy performance of the learning model culminated, achieving 100% identification accuracy of OFDM subcarrier signals. Under weak turbulent atmospheric and time-varying channel conditions, the overall identification accuracy curve tended to increase as SNR increased and stabilized at more than 95%. Compared with the two comparison methods, the proposed method reduced the sensitivity to channel variations and improved the convergence speed on the basis of the guaranteed identification accuracy, and enabled reliable identification of OFDM subcarrier signals in a wide SNR range.
Transaction Model Based on Stackelberg Game Method for Balancing Supply and Demand Sides of Multi-Energy Microgrid
Authors: Wei Meifang , Deng Youyue , Long Min , Wang Yahui , Li Yong
Published: February 2022

To improve the coordination and complementarity of multiple energy sources, balancing the interests of different participants in a multi-energy system is of great importance. However, traditional centralized optimization can hardly reflect the game relationship between supply side and demand sides. A trading model based on the Stackelberg game model is proposed in this paper to balance the interests of the supply side and demand side and reduce the carbon emissions. First of all, the process of trading between the supply side and demand side based on smart contracts is described. A contractual consensus is obtained through an internal game, and the transaction is completed automatically. Secondly, a bilevel optimization model is established to coordinate the benefits of both parties based on the Stackelberg game model. The energy operator acts as a leader, and considers the two objectives, i.e., maximizing net income and minimizing carbon emissions, and uses the linear weighting method to convert the dual objectives into single objective. Users act as followers and aim to increase the comprehensive benefits, including energy cost and comfort. Then, Karush–Kuhn–Tucker optimality condition is used to transform the bilevel optimization model into an equivalent single-level model. Finally, simulation results show that the proposed method can coordinate the economic interests of both sides of supply and demand and effectively reduce the carbon emissions of the energy operator.
A Simulation Experimental Study on the Advance Support Mechanism of a Roadway Used with the Longwall Coal Mining Method
Authors: Liu Hui , Jiang Zhenhua , Chen Wansheng , Chen Fei , Ma Fenglin , Li Donghao , Liu Zhaoyang , Gao Hongke
Published: February 2022

Aiming to advance a support problem for roadways used with the longwall coal mining method, the S1202 working face of the Ningtiaota Coal Mine is taken as the engineering background. The monitoring and analysis of bolt force, anchor cable force and surrounding rock deformation of two types of roadways within the whole advance pressure influence range are carried out in the present paper. Based on this, a numerical calculation model consistent with the field is established, and numerical comparison tests under different influencing factors are carried out. The rationality of the numerical test results is verified by using the field monitoring data. At the same time, quantitative evaluation indexes, such as characterization deformation, are established, and the deformation law of roadways surrounding rocks under different advance passive support forces is analyzed. The advance support mechanism of the roadway used with the longwall coal mining method is clarified. The test shows that under the condition of no advance passive support, the maximum characteristic deformation of surrounding rock in the haulage roadway and ventilation roadway is 7.1 cm and 10.1 cm, respectively. The above surrounding rock deformation still meets the requirements of on-site safety production. The research results can provide experimental support for the advance support parameters of the roadway used with the longwall coal mining method.
Legal Framework for the Sustainable Production of Short Rotation Coppice Biomass for Bioeconomy and Bioenergy
Authors: Zięty Jakub Jan , Olba-Zięty Ewelina , Stolarski Mariusz Jerzy , Krzykowski Michał , Krzyżaniak Michał
Published: February 2022

The production of lignocellulose biomass on dedicated plantations is an option that facilitates the implementation of sustainable development policy. The novelty of this type of research is that it involves the use of various types of methods—economic and legal analyses within a particular subject. This makes it possible to obtain a holistic view of the chosen case study. The purpose of this study was to determine whether setting up a Short Rotation Coppice (SRC) plantation of willow (Salix spp.) and poplar (Populus spp.) was economically profitable and if the legal regulations supported this type of production. The economic data are based on an experimental case study. The economic profitability of the plantations was assessed through an analysis of discounted cash flows, net present value (NPV), internal rate of return (IRR), and profitability index (PI). The legal analysis of the relevant EU and Polish legal solutions was based on a dogmatic approach. The study demonstrated that SRC cultivation was mostly hindered by economic factors, including the low selling price of biomass as an energy resource and the high costs of harvest. Meanwhile, in the analysed period, i.e., from 2015 to 2020, there were no additional legal or economic forms of support for this type of production that was addressed directly to lignocellulose biomass producers, with the exception of the standard support under the Common Agricultural Policy framework. The results of this study provide information for decisionmakers about the opportunities and challenges experienced during the development of SRC plantations.
Research on Thermodynamic Characteristics of Hydraulic Power Take-Off System in Wave Energy Converter
Authors: Niu Yubo , Gu Xingyuan , Yue Xuhui , Zheng Yang , He Peijie , Chen Qijuan
Published: February 2022

Hydraulic power-take-off (PTO) systems which utilize high-pressure oil circuits to transmit energy are widely applied in wave energy generation. The properties of hydraulic oil are significantly influenced by environmental conditions, and its dynamic viscosity is sensitive to temperature, especially in relatively low-temperature cases. This paper studies the characteristics of the hydraulic PTO when started in different temperature conditions via numerical analysis and experimental verification. An improved numerical model of the hydraulic PTO system is proposed, in which the effects of temperature on the hydraulic oil viscosity and hydraulic motor efficiency are quantitatively investigated, and consequently, the thermal-hydraulic characteristics can be sufficiently considered. The performances of the hydraulic PTO in start-up processes with different initial temperatures and in long term operation are assessed. The results show that the presented model can reasonably describe the hydraulic PTO characteristics. The efficiency of hydraulic PTO degrades when it starts at low temperatures. The efficiency increases in relatively high temperature, while larger fluctuations of the flow rate and output power are observed. This study can provide guidance for enhancing the efficiency and consistency of hydraulic PTO operating in actual sea conditions.
L0 and L1 Guidance and Path-Following Control for Airborne Wind Energy Systems
Authors: Fernandes Manuel C. R. M. , Vinha Sérgio , Paiva Luís Tiago , Fontes Fernando A. C. C.
Published: February 2022

For an efficient and reliable operation of an Airborne Wind Energy System, it is widely accepted that the kite should follow a pre-defined optimized path. In this article, we address the problem of designing a trajectory controller so that such path is closely followed. The path-following controllers investigated are based on a well-known nonlinear guidance logic termed L1 and on a proposed modification of it, which we termed L0. We have developed and implemented both L0 and L1 controllers for an AWES. The two controllers have an easy implementation with an explicit expression for the control law based on the cross-track error, on the heading angle relative to the path, and on a single parameter L (L0 or L1, depending on each controller) that we are able to tune. The L0 controller has an even easier implementation since the explicit control law can be used without the need to switch controllers. Since the switching of controllers might jeopardize stability, the L0 controller has an important theoretical advantage in being able to guarantee stability on a larger domain of attraction.The simulation study shows that both nonlinear guidance logic controllers exhibit appropriate performance when the L parameter is adequately tuned, with the L0 controller showing a better performance when measured in terms of the average cross-track error.
Dynamic Equivalents in Power System Studies: A Review
Authors: Sowa Paweł , Zychma Daria
Published: February 2022

In this paper, the available methods and procedures for creating equivalents for the analysis of electromagnetic transients in power systems are presented and discussed. General requirements of power system representation during simulation of electromagnetic transients are shown. The main available procedures are shown, along with an assessment of their advantages and disadvantages. Methods to search for the optimal replacement of structures in time and frequency domains are discussed. Optimization and direct methods in the frequency domain are presented. Each of these methods is discussed with respect to their possible use in determining the structure of the equivalent circuit for the study of electromagnetic phenomena. Methods to reduce a complex power system, as one of the approaches to determining the structure and parameters of the equivalent circuit, are also presented. Contraindications to the search for equivalents in the frequency domain to study electromagnetic transients are discussed. An analysis of methods for the identification of parameters of the equivalents is presented. The latest advances in the search for the structure and parameters of equivalents are presented, particularly the use of artificial neural networks in the process of replacing parts of systems. Finally, the analyses conducted in this study, together with recommendations regarding the choice of the procedure during the search for equivalents for the analysis of electromagnetic transient phenomena, are summarized.
Data Quality—Concepts and Problems
Authors: Hassenstein Max J. , Vanella Patrizio
Published: February 2022

Data Quality is, in essence, understood as the degree to which the data of interest satisfies the requirements, is free of flaws, and is suited for the intended purpose. Data Quality is usually measured utilizing several criteria, which may differ in terms of assigned importance, depending on, e.g., the data at hand, stakeholders, or the intended use.
Growth Rate and Leaf Functional Traits of Four Broad-Leaved Species Underplanted in Chinese Fir Plantations with Different Tree Density Levels
Authors: Xu Rui , Wang Liyan , Zhang Jian , Zhou Jing , Cheng Shundan , Tigabu Mulualem , Ma Xiangqing , Wu Pengfei , Li Ming
Published: February 2022

The close-to-Nature management method of interplanting broad-leaved trees after thinning of monoculture plantations is an important mixed species restoration model to improve the ecological service and functions effectively as well as to reduce the productivity decline of the multi-generation continuous planting of monoculture. Thus, the selection of tree species for establishing mixed forest and its ecological adaptability are the key issues. In this study, we conducted thinning experiment in an 11-year-old Chinese fir plantation with retention density of 900 trees/ha, 1200 trees/ha and 1875 trees/ha, and then underplanted four broad-leaved species, Schima superba, Phoebe bournei, Tsoongiodendron odorum and Michelia macclurei. After three years, we analyzed the growth rate and leaf functional traits of the broad-leaved species and their correlations with stand characteristics. The results showed that growth rate of seedlings of the four broad-leaved species were significantly different (p < 0.05) among different tree density levels and species. Low tree density favored seedling growth compared with high tree density and seedlings of T. odorum and S. superba performed best. However, leaf functional traits varied significantly (p < 0.01) among species only, and T. odorum had the largest specific leaf area, the smallest leaf mass per unit area, the smallest leaf tissue density, relatively large leaf thickness, and relatively small dry matter content. The leaf C content varied significantly among tree density levels and species; leaf N content varied significantly among species only; and leaf p content varied among tree density levels only. Correlation analyses between growth characters and leaf functional traits showed that height growth was significantly correlated with leaf N content (r = 0.686; p = 0.041) and with C:N ratio (r = −0.682; p = 0.043). Root collar diameter growth was significantly correlated with specific leaf area (r = 0.820; p = 0.007), leaf N content (r = 0.685; p = 0.042), leaf thickness (r = −0.706; p = 0.034) and leaf mass per unit area (r = −0.812; p = 0.008). Thus, leaf functional traits possibly predict diameter growth better than height growth. As a whole, growth rate and leaf functional traits could be used as a guide for selection of species for under planting in thinned pure monoculture plantations to establish conifer-broadleaved mixed forests. Based on growth rate and leaf functional traits, T. odorum appeared to be suitable for planting under low tree density stands where the degree of shading is low.
Parametric Analysis of a Steel Frame under Fire Loading Using Monte Carlo Simulation
Authors: Almadani Ragad , Fu Feng
Published: February 2022

In this paper, the parametric analysis of the thermal and structural response of a two-storey, single-zone steel frame building on fire is made considering different parameters Monte Carlo simulation is used to generate random variables for the opening factor, fire compartment area and finally the beam flange thickness. Using the random parameter generated, a sequential thermal and mechanical analysis was conducted using the finite element software ABAQUS. The first step was a heat transfer analysis, followed by mechanical analysis. The effect of different parameters on the thermal and mechanical response of the structure was studied.
Application of an Integral Turbulence Model to Close the Model of an Anisotropic Porous Body as Applied to Rod Structures
Authors: Vlasov Maksim N. , Merinov Igor G.
Published: February 2022

In practice, often devices are ordered rod structures consisting of a large number of rods. Heat exchangers, fuel assemblies of nuclear reactors, and their cores in the case of using caseless assemblies are examples of such devices. Simulation of heat and mass transfer processes in such devices in porous-body approximation can significantly reduce the required resources compared to computational fluid dynamics (CFD) approaches. The paper describes an integral turbulence model developed for defining anisotropic model parameters of a porous body. The parameters of the integral turbulence model were determined by numerical simulations for assemblies of smooth rods, assemblies with spacer grids, and wire-wrapped fuel assemblies. The results of modeling the flow of a liquid metal coolant in an experimental fuel assembly with local blocking of its flow section in anisotropic porous-body approximation using an integral turbulence model are described. The possibility of using the model of an anisotropic porous body with the integral model of turbulence to describe thermal-hydraulic processes during fluid flow in rod structures is confirmed.
Effects of Catfish (Ictalurus punctatus) Bone Powder on Consumers’ Liking, Emotions, and Purchase Intent of Fried Catfish Strips
Authors: Murillo Silvia , Ardoin Ryan , Watts Evelyn , Prinyawiwatkul Witoon
Published: February 2022

Catfish are the predominant U.S. aquacultural product. However, byproducts from filleting, including bones that are high in calcium, typically go to waste or are sold as a low-valued feed. This research evaluated the potential use of catfish bone powder (CBP; 21.07% calcium) as a food ingredient. Catfish fillet strips were dredged with a breading mix (CBPM) containing 0% (0CBPM), 10% (10CBPM), and 20% (20CBPM) CBP before frying. Consumers (N = 211) evaluated sensory liking (nine-point hedonic scale) and attribute intensity (JAR scale), emotions (check-all-that-apply), and purchase intent (PI, yes/no) of samples. Color and texture were measured instrumentally. CBP did not show any negative effects on liking scores, although crispiness was scored higher for 20CBPM (mean = 6.88) than 10CBPM (mean = 6.43). Positive emotions were most relevant to CBP-containing samples, with significantly higher rates of adventurous and understanding. Information about calcium fortification using CBP increased PI to 81.04% for the 10CBPM and 83.89% for the 20CBPM samples and showed a greater effect on Latin Americans/Hispanics than U.S. Americans. Consumers were not averse to the consumption of CBP which can contribute to sustainable nutrition through waste reduction. Successful calcium fortification of fried catfish dredged with 20% CBP did not compromise sensory liking and may be feasible in other products.
Strategies for Biocontrol of Listeria monocytogenes Using Lactic Acid Bacteria and Their Metabolites in Ready-to-Eat Meat- and Dairy-Ripened Products
Authors: Martín Irene , Rodríguez Alicia , Delgado Josué , Córdoba Juan J.
Published: February 2022

Listeria monocytogenes is one of the most important foodborne pathogens. This microorganism is a serious concern in the ready-to-eat (RTE) meat and dairy-ripened products industries. The use of lactic acid bacteria (LAB)-producing anti-L. monocytogenes peptides (bacteriocins) and/or lactic acid and/or other antimicrobial system could be a promising tool to control this pathogen in RTE meat and dairy products. This review provides an up to date about the strategies of use of LAB and their metabolites in RTE meat products and dairy foods by selecting the most appropriate strains, by analysing the mechanism by which they inhibit L. monocytogenes and methods of effective application of LAB, and their metabolites in these kinds of products to control this pathogen throughout the processing and storage. The selection of LAB with anti-L. monocytogenes activity allows to dispose of effective strains in meat and dairy-ripened products, achieving reductions form 2–5 logarithmic cycles of this pathogen throughout the ripening process. The combination of selected LAB strains with antimicrobial compounds, such as acid/sodium lactate and other strategies, as the active packaging could be the next future innovation for eliminating risk of L. monocytogenes in meat and dairy-ripened products.