bluuebunny/crossref_metadata_2025 huggingface dataset:
Well-posedness in weighted spaces for the generalized Hartree equation with p < 2
Authors: Arora Anudeep K. , Riaño Oscar , Roudenko Svetlana
Published: August 2021

We investigate the well-posedness in the generalized Hartree equation [Formula: see text], [Formula: see text], [Formula: see text], for low powers of nonlinearity, [Formula: see text]. We establish the local well-posedness for a class of data in weighted Sobolev spaces, following ideas of Cazenave and Naumkin, Local existence, global existence, and scattering for the nonlinear Schrödinger equation, Comm. Contemp. Math. 19(2) (2017) 1650038. This crucially relies on the boundedness of the Riesz transform in weighted Lebesgue spaces. As a consequence, we obtain a class of data that exists globally, moreover, scatters in positive time. Furthermore, in the focusing case in the [Formula: see text]-supercritical setting we obtain a subset of locally well-posed data with positive energy, which blows up in finite time.
Modeling of Electric Discharge Wire Cut of Aviation Grade Alloy Using Fuzzy Technique
Authors: Singh Thakur , Kumar Pawan , Kumar Jatinder , Misra Joy Prakash
Published: August 2021

Fuzzy modeling technique is obtaining a huge revelation as prospective modeling for solving and modeling of manufacturing issues. In this research paper, fuzzy modeling technique is applied for analyzing and predicting the MRR, SR and CR during machining of aviation-grade aluminum alloy. Pulse-on time ([Formula: see text]), pulse-off time ([Formula: see text]), peak-current ([Formula: see text]) and servo-voltage ([Formula: see text]) are used as process variables. The different combinations of process variables for experimentation are designed using Box–Behnken design (BBD) of Response Surface Methodology (RSM). Results showed that [Formula: see text] is the most significant parameter for CR, MRR and SR, followed by [Formula: see text] and [Formula: see text]. It is observed that [Formula: see text] has less significance in response parameters. The confirmation experiments have also been carried out to justify the result procured by the fuzzy model. The root mean square error (RMSE) of CR, MRR and SR is 3.633, 3.586 and 3.366, respectively. Additionally, microstructure variations of machined surface are evaluated by scanning electron microscope (SEM). Micro-cracks, wire tool marks, craters and lump of debris are seen on WEDMed surfaces.
Instrument Identification Technology Based on Deep Learning
Authors: Song Yunhai , Zhou Zhenzhen , Zhang Hourong , Su Haohui , Zhang Han , Wang Qi
Published: August 2021

With the continuous improvement of science and technology, the substation remote control system has been constantly improved, which provides the possibility for the complete realization of intelligent and unmanned substation. However, due to the special substation environment, it is easy to cause interference, coupled with the low accuracy of today’s video image processing algorithm, which leads to the frequent occurrence of false alarms and missing alarms. Manual intervention is needed to deal with this, which inhibits the display of automatic intelligent substation processing functions. Therefore, in this paper, the most rapidly developed machine learning algorithm — deep learning is applied to the substation instrument equipment identification processing, in order to improve the accuracy and efficiency of instrument equipment identification, and make due contributions to the full realization of unattended substation.
Calibration of naturally fractured reservoir models using integrated well-test analysis – an illustration with field data from the Barents Sea
Authors: Egya David O. , Corbett Patrick W. M. , Geiger Sebastian , Norgard Jens-Petter , Hegndal-Andersen Søren
Published: August 2021

This paper successfully applied the geoengineering workflow for integrated well-test analysis to characterize fluid flow in a newly discovered fractured reservoir in the Barents Sea. A reservoir model containing fractures and matrix was built and calibrated using this workflow to match complex pressure transients measured in the field. We outline different geological scenarios that could potentially reproduce the pressure response observed in the field, highlighting the challenge of non-uniqueness when analysing well-test data. However, integrating other field data into the analysis allowed us to narrow the range of uncertainty, enabling the most plausible geological scenario to be taken forward for more detailed reservoir characterization and history matching. The results provide new insights into the reservoir geology and the key flow processes that generate the pressure response observed in the field. This paper demonstrates that the geoengineering workflow used here can be applied to better characterize naturally fractured reservoirs. We also provide reference solutions for interpreting well tests in fractured reservoirs where troughs in the pressure derivative are recognizable in the data.
Exploring the Experience of Contemporary Dance Practices in the Context of Global Art Choreography in the Museum Space
Authors: Portnova Tatiana V.
Published: August 2021

The purpose of the article is to examine modern projects in the field of choreography, interconnected with art museums that open doors for choreographers and together embody creative ideas. It is this creative, largely subjective, controversial dialogue between the museum and dance, accompanied by comments of art historians, choreographers, and artists, that gets its meaning in the presented material. The novelty of the study lies in assessing the main directions of choreographic activity, which can be mutually transformed so that the museum and dance function successfully in modern conditions and build a new communicative space with the audience. Through a creative analysis of the modern experience of dance practices, it is possible to discover the principles and trends that are destined to breathe new life into the museum space. The considered examples of organising a museum space with theatrical and plastic direction interacting with it clearly demonstrate that modern visual strategies, associated primarily with its interactive substance, affect the communicative and exhibition space of the museum in different ways. A choreographic performance was analysed as part of a diverse event taking place on the territory of the cultural and historical museum complex; inclusion of dance in the dynamics of the halls of the interior spaces of the museum; entry of a choreographic performance, theatrical actions into the exhibition space of expositions; the museum itself inviting artists, choreographic schools and studios to conduct regular classes and masterclasses within the walls of the museum to popularise its collections, and other examples of forms of interaction between the art of dance and the art museum.
Desire
: Leveraging the Best of Centralized and Decentralized Contact Tracing Systems
Authors: Boutet Antoine , Castelluccia Claude , Cunche Mathieu , Lauradou Cédric , Roca Vincent , Baud Adrien , Raverdy Pierre-Guillaume
Published: August 2021

Contact tracing in case of pandemic is becoming an essential mitigation tool for national health services to break infection chains and prevent the virus from spreading further. To support manual tracing, several countries have been developing contact tracing apps that detect nearby mobile phones using Bluetooth. Such data collection raised privacy concerns and several privacy-preserving protocols have been proposed to prevent the leakage of personal and sensitive information. These solutions are mainly divided into two categories using a centralized or a decentralized exposure score computation. However, both approaches depict limitations.

This article presents
Desire
, a novel exposure notification system that leverages the best of centralized and decentralized systems. As opposed to existing contact tracing schemes,
Desire
leverages Private Encounter Tokens (
Pets
) generated locally on the device that uniquely identify an encounter between two nodes while being private and unlinkable by the server. The role of the server is merely to match PETs generated by diagnosed users with the pets provided by requesting users. Our privacy risk analysis shows that
Desire
drastically improves privacy against malicious users (i.e., limitation of decentralized systems) and authority (i.e., limitation of centralised systems). We implemented
Desire
, evaluated it in real condition, and show it feasibility.
Coopetition in IR research
Authors: Voorhees Ellen M.
Published: August 2021

Coopetition is defined as competitors cooperating for the common good, an apt description of the community evaluations such as TREC that build infrastructure to support information retrieval (IR) research. This note summarizes the main points of a keynote talk presented at SIGIR 2020 that looks at the benefits and risks coopetition can engender in IR research.
Report on the first workshop on bias in automatic knowledge graph construction at AKBC 2020
Authors: Safavi Tara , Meij Edgar , Özcan Fatma , Redi Miriam , Demartini Gianluca , Xiong Chenyan
Published: August 2021

We report on the First Workshop on Bias in Automatic Knowledge Graph Construction (KG-BIAS), which was co-located with the Automated Knowledge Base Construction (AKBC) 2020 conference. Identifying and possibly remediating any sort of bias in knowledge graphs, or in the methods used to construct or query them, has clear implications for downstream systems accessing and using the information in such graphs. However, this topic remains relatively unstudied, so our main aim for organizing this workshop was to bring together a group of people from a variety of backgrounds with an interest in the topic, in order to arrive at a shared definition and roadmap for the future. Through a program that included two keynotes, an invited paper, three peer-reviewed full papers, and a plenary discussion, we have made initial inroads towards a common understanding and shared research agenda for this timely and important topic.
Report on CLEF 2020
Authors: Arampatzis Avi , Cappellato Linda , Eickhoff Carsten , Ferro Nicola , Joho Hideo , Kanoulas Evangelos , Lioma Christina , Névéol Aurélie , Tsikrika Theodora , Vrochidis Stefanos
Published: August 2021

This is a report on the tenth edition of the
Conference and Labs of the Evaluation Forum
(CLEF 2020), (virtually) held from September 22--25, 2020, in Thessaloniki, Greece.

CLEF was a four day event combining a Conference and an Evaluation Forum. The Conference featured keynotes by Ellen Voorhees and Yiannis Kompasiaris, and presentation of peer reviewed research papers covering a wide range of topics in addition to many posters. The Evaluation Forum consisted to twelve Labs: ARQMath, BioASQ, CheckThat!, ChEMU, CLEF eHealth, eRisk, HIPE, ImageCLEF, LifeCLEF, LiLAS, PAN, and Touché, addressing a wide range of tasks, media, languages, and ways to go beyond standard test collections.
Cheap IR evaluation
Authors: Roitero Kevin
Published: August 2021

To evaluate Information Retrieval (IR) effectiveness, a possible approach is to use test collections, which are composed of a collection of documents, a set of description of information needs (called topics), and a set of relevant documents to each topic. Test collections are modelled in a competition scenario: for example, in the well known TREC initiative, participants run their own retrieval systems over a set of topics and they provide a ranked list of retrieved documents; some of the retrieved documents (usually the first ranked) constitute the so called pool, and their relevance is evaluated by human assessors; the document list is then used to compute effectiveness metrics and rank the participant systems. Private Web Search companies also run their in-house evaluation exercises; although the details are mostly unknown, and the aims are somehow different, the overall approach shares several issues with the test collection approach.

The aim of this work is to: (i) develop and improve some state-of-the-art work on the evaluation of IR effectiveness while saving resources, and (ii) propose a novel, more principled and engineered, overall approach to test collection based effectiveness evaluation.

In this thesis we focus on three main directions: the first part details the usage of few topics (i.e., information needs) in retrieval evaluation and shows an extensive study detailing the effect of using fewer topics for retrieval evaluation in terms of number of topics, topics subsets, and statistical power. The second part of this thesis discusses the evaluation without relevance judgements, reproducing, extending, and generalizing state-of-the-art methods and investigating their combinations by means of data fusion techniques and machine learning. Finally, the third part uses crowdsourcing to gather relevance labels, and in particular shows the effect of using fine grained judgement scales; furthermore, explores methods to transform judgements between different relevance scales.

Awarded by:
University of Udine, Udine, Italy on 19 March 2020.

Supervised by:
Professor Stefano Mizzaro.

Available at:
https://kevinroitero.com/resources/kr-phd-thesis.pdf.
Koli Calling is online
Authors: Otto Seppälä , Petersen Andrew
Published: August 2021

Koli Calling is a single-track international conference dedicated to the scholarship of teaching and learning and to education research in computing. The conference is known for its moderate size, intimate atmosphere, and lively discussions.
2022 SIGCSE board election
Authors: Settle Amber
Published: August 2021

Every three years SIGCSE holds elections for seven positions on the Executive Board overseeing the organization, namely Chair, Vice-Chair, Secretary, Treasurer, and three At-Large members. The previous SIGCSE Chair serves on each Executive Board as the Immediate Past Chair. A description of each position is found in the SIGCSE by-laws: https://sigcse.org/policies/bylaws.html.
Restoring Degraded Lands
Authors: Arneth Almut , Olsson Lennart , Cowie Annette , Erb Karl-Heinz , Hurlbert Margot , Kurz Werner A. , Mirzabaev Alisher , Rounsevell Mark D.A.
Published: August 2021

Land degradation continues to be an enormous challenge to human societies, reducing food security, emitting greenhouse gases and aerosols, driving the loss of biodiversity, polluting water, and undermining a wide range of ecosystem services beyond food supply and water and climate regulation. Climate change will exacerbate several degradation processes. Investment in diverse restoration efforts, including sustainable agricultural and forest land management, as well as land set aside for conservation wherever possible, will generate co-benefits for climate change mitigation and adaptation and morebroadly for human and societal well-being and the economy. This review highlights the magnitude of the degradation problem and some of the key challenges for ecological restoration. There are biophysical as well as societal limits to restoration. Better integrating policies to jointly address poverty, land degradation, and greenhouse gas emissions and removals is fundamental to reducing many existing barriers and contributing to climate-resilient sustainable development.
Wild Meat Is Still on the Menu: Progress in Wild Meat Research, Policy, and Practice from 2002 to 2020
Authors: Ingram Daniel J. , Coad Lauren , Milner-Gulland E.J. , Parry Luke , Wilkie David , Bakarr Mohamed I. , Benítez-López Ana , Bennett Elizabeth L. , Bodmer Richard , Cowlishaw Guy , El Bizri Hani R. , Eves Heather E. , Fa Julia E. , Golden Christopher D. , Iponga Donald Midoko , Minh Nguyễn Văn , Morcatty Thais Q. , Mwinyihali Robert , Nasi Robert , Nijman Vincent , Ntiamoa-Baidu Yaa , Pattiselanno Freddy , Peres Carlos A. , Rao Madhu , Robinson John G. , Rowcliffe J. Marcus , Stafford Ciara , Supuma Miriam , Tarla Francis Nchembi , van Vliet Nathalie , Wieland Michelle , Abernethy Katharine
Published: August 2021

Several hundred species are hunted for wild meat in the tropics, supporting the diets, customs, and livelihoods of millions of people. However, unsustainable hunting is one of the most urgent threats to wildlife and ecosystems worldwide and has serious ramifications for people whose subsistence and income are tied to wild meat. Over the past 18 years, although research efforts have increased, scientific knowledge has largely not translated into action. One major barrier to progress has been insufficient monitoring and evaluation, meaning that the effectiveness of interventions cannot be ascertained. Emerging issues include the difficulty of designing regulatory frameworks that disentangle the different purposes of hunting, the large scale of urban consumption, and the implications of wild meat consumption for human health. To address these intractable challenges, wepropose eight new recommendations for research and action for sustainable wild meat use, which would support the achievement of the United Nations Sustainable Development Goals.
The Rise of State-Owned Investors: Sovereign Wealth Funds and Public Pension Funds
Authors: Megginson William L. , Lopez Diego , Malik Asif I.
Published: August 2021

State-owned investors (SOIs), including sovereign wealth funds and public pension funds, have $27 trillion in assets under management in 2020, making these funds the third largest group of asset owners globally. SOIs have become the largest and are among the most important private equity investors, and they are key investors in other alternative asset investments such as real estate, infrastructure, and hedge funds. SOIs are also leaders in promoting environmental, social, and governance policies and corporate social responsibility policies in investee companies. We document the rise of SOIs, assess their current investment policies, and describe how their state ownership both constrains and enhances their investment opportunity sets. We survey the most impactful recent academic research on sovereign wealth funds, public pension funds, and their closest financial analogs, private pension funds. We also introduce a new Governance-Sustainability-Resilience Scoreboard for SOIs and survey research examining their role in promoting good corporate governance.
The Physiology and Biogeochemistry of SUP05
Authors: Morris Robert M. , Spietz Rachel L.
Published: August 2021

The SUP05 clade of gammaproteobacteria (Thioglobaceae) comprises both primary producers and primary consumers of organic carbon in the oceans. Host-associated autotrophs are a principal source of carbon and other nutrients for deep-sea eukaryotes at hydrothermal vents, and their free-living relatives are a primary source of organic matter in seawater at vents and in marine oxygen minimum zones. Similar to other abundant marine heterotrophs, such as SAR11 and Roseobacter, heterotrophic Thioglobaceae use the dilute pool of osmolytes produced by phytoplankton for growth, including methylated amines and sulfonates. Heterotrophic members are common throughout the ocean, and autotrophic members are abundant at hydrothermal vents and in anoxic waters; combined, they can account for more than 50% of the total bacterial community. Studies of both cultured and uncultured representatives from this diverse family are providing novel insights into the shifting biogeochemical roles of autotrophic and heterotrophic bacteria that cross oxic–anoxic boundary layers in the ocean.
The History of Ocean Oxygenation
Authors: Reinhard Christopher T. , Planavsky Noah J.
Published: August 2021

The large-scale dynamics of ocean oxygenation have changed dramatically throughout Earth's history, in step with major changes in the abundance of O2in the atmosphere and changes to marine nutrient availability. A comprehensive mechanistic understanding of this history requires insights from oceanography, marine geology, geochemistry, geomicrobiology, evolutionary ecology, and Earth system modeling. Here, we attempt to synthesize the major features of evolving ocean oxygenation on Earth through more than 3 billion years of planetary history. We review the fundamental first-order controls on ocean oxygen distribution and summarize the current understanding of the history of ocean oxygenation on Earth from empirical and theoretical perspectives—integrating geochemical reconstructions of oceanic and atmospheric chemistry, genomic constraints on evolving microbial metabolism, and mechanistic biogeochemical models. These changes are used to illustrate primary regimes of large-scale ocean oxygenation and to highlight feedbacks that can act to stabilize and destabilize the ocean–atmosphere system in anoxic, low-oxygen, and high-oxygen states.
The Enzymology of Ocean Global Change
Authors: Hutchins David A. , Sañudo-Wilhelmy Sergio A.
Published: August 2021

A small subset of marine microbial enzymes and surface transporters have a disproportionately important influence on the cycling of carbon and nutrients in the global ocean. As a result, they largely determine marine biological productivity and have been the focus of considerable research attention from microbial oceanographers. Like all biological catalysts, the activity of these keystone biomolecules is subject to control by temperature and pH, leaving the crucial ecosystem functions they support potentially vulnerable to anthropogenic environmental change. We summarize and discuss both consensus and conflicting evidence on the effects of sea surface warming and ocean acidification for five of these critical enzymes [carbonic anhydrase, ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), nitrogenase, nitrate reductase, and ammonia monooxygenase] and one important transporter (proteorhodopsin). Finally, we forecast how the responses of these few but essential biocatalysts to ongoing global change processes may ultimately help to shape the microbial communities and biogeochemical cycles of the future greenhouse ocean.
Neurologic Manifestations and Complications of COVID-19
Authors: Hensley Matthew K. , Markantone Desiree , Prescott Hallie C.
Published: August 2021

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has created a global pandemic. Beyond the well-described respiratory manifestations, SARS-CoV-2 may cause a variety of neurologic complications, including headaches, alteration in taste and smell, encephalopathy, cerebrovascular disease, myopathy, psychiatric diseases, and ocular disorders. Herein we describe SARS-CoV-2’s mechanism of neuroinvasion and the epidemiology, outcomes, and treatments for neurologic manifestations of COVID-19.
ETB receptor-mediated vasodilation is regulated by estradiol in young women
Authors: Shoemaker Leena N. , Haigh Katherine M. , Kuczmarski Andrew V. , McGinty Shane J. , Welti Laura M. , Hobson Joshua C. , Edwards David G. , Feinberg Ronald F. , Wenner Megan M.
Published: August 2021

The endothelin-B (ETB) receptor mediates vasodilation in young women, an effect lost following menopause. It is unclear whether these alterations are due to aging or changes in estradiol (E2). During endogenous hormone suppression (GnRH antagonist), blockade of ETB receptors enhanced cutaneous microvascular vasodilation. However, during E2 administration, blockade of ETB receptors attenuated vasodilation, indicating that the ETB receptor mediates dilation in the presence of E2. In young women, ETB receptors mediate vasodilation in the presence of E2, an effect that is lost when E2 is suppressed.
Immune cell β2-adrenergic receptors contribute to the development of heart failure
Authors: Tanner Miles A. , Maitz Charles A. , Grisanti Laurel A.
Published: August 2021

Immune cell β2-adrenergic receptors (β2ARs) are important for proinflammatory macrophage infiltration to the heart in a chronic isoproterenol administration model of heart failure. Mice lacking immune cell β2AR have decreased immune cell infiltration to their heart, primarily proinflammatory macrophage populations. This decrease culminated to decreased cardiac injury with lessened cardiomyocyte death, decreased interstitial fibrosis and hypertrophy, and improved function demonstrating that β2AR regulation of immune responses plays an important role in the heart’s response to persistent βAR stimulation.
Cropping Practices and Effects on Soil Nutrient Adequacy Levels and Cassava Yield of Smallholder Farmers in Northern Zambia
Authors: Kaluba Peter , Mwamba Sydney , Moualeu-Ngangue Dany Pascal , Chiona Martin , Munyinda Kalaluka , Winter Etti , Stützel Hartmut , Chishala Benson H.
Published: August 2021

Cassava is a staple food and a major source of income for many smallholder farmers. However, its yields are less than 6 t ha−1 compared to a potential yield of 20–25 t ha−1 in Zambia. Understanding cropping practices and constraints in cassava production systems is imperative for sustainable intensification. Therefore, a survey of 40 households each with three fields of cassava at 12, 24, and 36 months after planting (MAP) was conducted. Analyzed soil data, leaf area index (LAI), intercepted photosynthetically active radiation, and management practices from 120 fields were collected and subjected to descriptive statistics. To explain yield differences within the same cassava growth stage group, the data were grouped into low- and high-yield categories using the median, before applying a nonparametric test for one independent sample. Stepwise regressions were performed on each growth stage and the whole dataset to determine factors affecting tuber yield. Cassava intercropping and monocropping systems were the main cropping systems for the 12 and 24–36 MAP, respectively. Cassava yields declined by 209 and 633 kg ha−1 at 12 and 36 MAP due to soil nutrient depletion for each year of cultivation until field abandonment at 8–9 years. Fresh cassava yields ranged from 3.51–8.51, 13.52–25.84, and 16.92–30.98 t ha−1 at 12, 24, and 36 MAP, respectively. For every one unit increment in exchangeable K (cmol (+)/kg soil), cassava yield increased by 435, 268, and 406 kg ha−1 at 12, 24, and 36 MAP, respectively. One unit increment of magnesium (cmol (+)/kg soil) gave the highest yield increase of 525 kg ha−1 at 24 MAP. The low levels of soil organic carbon explained the deficient nitrogen in cassava fields, which limits the LAI growth and consequently reduced intercepted radiation and low yields. The effect of exchangeable K on growth was limited by the moderate availability of Mg and low N, thus the need for balanced fertilizer regimes.
Experimental Study on Interaction between Nanosecond Pulsed Laser and Normal Shock Wave
Authors: Shi Jilin , Wang Diankai , Huang Longcheng
Published: August 2021

Nanosecond pulsed lasers possess two remarkable advantages: a high peak power density and the ability to break down air to form plasma readily. Therefore, they have significant practical value in the drag reduction of a supersonic body. An experimental investigation is conducted on the fundamental physical phenomenon of the interaction of the pulsed laser plasma with a normal shock wave to reveal the mechanism of drag reduction. Moreover, a high‐precision schlieren system is developed to measure complex wave structures with a time resolution of up to 30 ns and a spatial resolution up to 1 mm. A high‐speed particle image velocimetry system is set up to measure the velocity and vorticity of the flow field quantitatively; the system has a time resolution of up to 500 ns. The characteristics of the spherical shock wave and the high‐temperature and low‐density region induced by the laser plasma are presented. The flow characteristics and evolution process of the laser plasma under a normal shock wave are substantially revealed. The cause of the supersonic drag reduction by the pulsed laser plasma is illustrated with numerical simulation results. The following results are obtained in this study: the initial Mach number of the shock wave induced by the laser plasma increases with the laser energy, and the shape of the wave gradually evolves from a droplet shape to a spherical shape. The propagation velocity decreases with time and is close to the sound velocity after 50 μs. The shape of the initial high‐temperature and low‐density region is approximately spherical; it subsequently destabilizes to form a sharp spike structure in the laser’s incident direction. Ultimately, the region evolves into a double‐vortex ring structure with upper and lower symmetry; the size of this region increases with the laser energy.
Optimal Power Flow Algorithm Based on Second‐Order Cone Relaxation Method for Electricity‐Gas Integrated Energy Microgrid
Authors: Zhang Fan , Shen Zhuzheng , Xu Wen , Wang Guofeng , Yi Biyi
Published: August 2021

Due to the existence of nonlinear constraints, it is difficult to solve the power flow directly. This paper proposes a microgrid optimal scheduling strategy using second‐order cone relaxation method to realize linear transformation, so as to minimize the total cost of the microgrid. Firstly, a microgrid system model of electricity‐gas integrated energy is established, and the nonlinear constraints of branch power flow are transformed by the second‐order cone relaxation method. Then, based on the microgrid model, the application conditions of the second‐order cone relaxation transformation method are studied, and the optimal scheduling strategy with the total cost of microgrid as the objective function is proposed. In addition, in the case that the microgrid system does not meet the application conditions of second‐order cone programming, the optimization problem is solved by increasing the line loss. Finally, an example is given to verify the effectiveness of the proposed method.
Flipped Classroom for Motor Skills: What Factors Influence College Students’ Learning Effect?
Authors: Zhang Fengyan , Ma Baojuan , Ren Wengang
Published: August 2021

The study of motor skills is an essential course item for college students. Many college teachers try to introduce the flipped classroom mode into the teaching of motor skills. However, the influence of this mode on the learning effect of college students’ motor skills is uncertain. This paper builds a research model on the basis of literature review. This model is used to analyze the influence factors of flipped classroom on the learning effect of college students’ motor skills. Through questionnaire survey and empirical analysis, we verified the research hypothesis of each factor. The results show that video technical action display, video feedback of students’ technical action, and teaching interaction have a significant positive impact on the learning effect of college students’ motor skills in the flipped classroom, while video theory teaching has no significant impact. This study expands the application of flipped classroom in the field of motor skills and enriches the relevant literature of flipped classroom mode. Based on the findings of this study, we make the following recommendations: (1) teachers can use the way of video recording to display technical actions of motor skills, (2) students can use video feedback to communicate with the teacher about the learning of motor skills, and (3) flipped classroom needs to pay attention to the teaching interaction between teachers and students.
Spray-Dried Quercetin-Lactose Powders for Oral Tablets with Improved Dissolution Rates and Modified Material Properties
Authors: Li Long , Li Yuanwei , Wu Zhiying , Chen Jinhui , Chen Jia
Published: August 2021

This study is aimed at using spray drying method to codisperse it with the commonly used drug carrier lactose in different solvents and then pass it through a spray dryer to obtain different samples. The results showed that the dissolution rate and solubility of the samples obtained by dispersion in hot water and 25% ethanol were significantly higher. The water of crystallization peaks of the raw material disappeared at 105-125°C and 130-150°C (DSC). The excipient lactose had a small upward exothermic peak at 177°C and a significant heat absorption peak at 209°C before untreated (XRD). α-Lactose peaks were observed at 12.5°, 19.1°, 19.6°, and 19.9° at 2θ in both samples, and β-lactose peaks were found at 10.5° at 2θ in sample A, but not in sample B (FTIR). The complex sharp peaks of lactose at 1100 cm-1 and quercetin at 1700-1000 cm-1 became moderated (SEM). The sample obtained by spray drying has a slit-type mesoporous structure with an average pore size of about 9.3 nm.
Design and Optimization of Smart Factory Control System Based on Digital Twin System Model
Authors: Bai Yan , You Jeong-Bong , Lee Il-Kyoo
Published: August 2021

Aiming at the problems of irrational allocation of resources, low efficiency caused by unbalanced production line layout, and slow production line upgrade of the smart factory, this paper builds a real physical smart factory platform through the optimal control strategy and uses the GRAFCET algorithm to optimize the logistics scheduling during the actual system operation. The genetic algorithm is used to optimize the layout effect of the production line; the digital twin technology is used to provide predictive analysis technical support for the upgrading and reengineering of the production line. Through the analysis and comparison of the production capacity and equipment utilization of the physical smart factory and the virtual smart factory processing scheme, practice shows that the design of the digital twin system can effectively improve the effect and accuracy of the lean production method in the production process reorganization. Quantitative analysis of manufacturing industry provides powerful theoretical and technical support.
[Retracted] Research and Application of Multifeature Gesture Recognition in Human‐Computer Interaction Based on Virtual Reality Technology
Authors: Feng Zhao , Wu Jinlong , Ni Taile
Published: August 2021

Objective. To explore the research and application of multifeature gesture recognition in virtual reality human‐computer interaction and to explore the gesture recognition technology scheme to achieve better human‐computer interaction experience. Methods. Through the study of the technical difficulties of gesture recognition, comparative static gesture feature recognition and feature fusion algorithms are applied, in the process of research on gesture partition, and adjust the contrast of characteristic parameters, combined with the feature of space‐time dynamic gesture tracking trajectory and dynamic gesture recognition and gesture recognition effect under different scheme. Results. The central region was divided into 0 regions, and the central region was divided into 1‐4 regions in counterclockwise direction. Compared with the traditional gesture changes, the overlapping problem in the four partition modes was reduced, the gesture was better displayed, and the operation and use of gesture processing were realized more efficiently. Conclusion. Gesture recognition requires the combination of static gesture feature information recognition, gesture feature fusion, spatiotemporal trajectory feature, and dynamic gesture trajectory feature to achieve a better human‐computer interaction experience.
Research on Deep‐Site Failure Mechanism of High‐Steep Slope under Active Fault Creeping Dislocation
Authors: Liu Yang , Zhang Kaiwen , Tian Denghang , Qu Liming , Liu Yang
Published: August 2021

The reverse thrust in the deep site causes the upward propagation of stress and displacement in the overlying soil. The displacement field around the fault zone is maximum. As the spatial location becomes shallower, the soil displacement gradually becomes smaller. The deformation of the overlying soil is mainly affected by the vertical dislocation of the fracture zone. The monitoring curve showed no abrupt change value, indicating that the top surface of soil did not rupture, and only the influence of fault on the displacement transfer of the top surface of the soil. When a creeping dislocation occurs in the bottom fracture zone, the maximum principal stress of the upper boundary of the deep site is dominated by compressive stress. The maximum principal stress of the soil on both sides of the fracture zone has a maximum value, and the soil on the right side of the fracture zone has a significant compression effect. The maximum principal stress monitoring curve varies greatly, indicating the plastic failure development of soil, which is the same as the research results of the plastic failure zone in the following paper. When the bottom fracture zone starts to move, the plastic zone first appears at the junction area between the front end of the bottom fracture zone and the overlying soil. As the amount of dislocation of the fracture zone increases, the plastic zone continues to extend into the inner soil. The left and right sides of the fracture zone show tensile failure and compression failure, respectively. The development of the upper envelope curve in the plastic zone of the overlying soil satisfies the Boltzmann equation with a first‐order exponential growth, while the development of the lower envelope curve satisfies the Gauss equation with a second‐order exponential growth. The development curve equation of the plastic zone is verified according to the residual figures of the fitting result and the correlation parameters.
Laparoscopic Diagnosis and Treatment of Gossypiboma Postconventional Ovariohysterectomy in a Bitch
Authors: Brun Maurício Veloso , Basso Paula Cristina , de Oliveira Marília Teresa , Dalmolin Fabíola , Pinto-Filho Saulo Tadeu Lemos , Hartmann Helen Fialho , Abati Stephanie Lanzarini , Machado-Silva Marco Augusto , Müller Daniel Curvello de Mendonça , Sanchez-Margallo Francisco Miguel
Published: August 2021

Introduction. Gossypiboma is a rare surgical complication in small animals. The authors reported the laparoscopic diagnosis and treatment of an abdominal gossypiboma and chronic draining fistula postopen ovariohysterectomy (OVH) unresponsive to medical treatment in a bitch. Case Presentation. The patient had undergone OVH and exploratory laparotomy in other veterinary practice 3 years previously. The animal, presenting a chronic fistula, was then referred to UFSM Veterinary Hospital. Ultrasonographic examination revealed a structure compatible with a granuloma. For the laparoscopic procedure, a 3-port (two at 11 mm; one at 6 mm) access was used. Adhesiolysis and mass removal were performed by blunt dissection and bipolar electrocoagulation. The fistula was treated by mobilising the omentum through it. There were no intra- or postoperative complications. The chronic wound showed first intention healing. The mass was composed of fibrous tissues surrounding one surgical gauze. Discussion and Conclusion. The removal of a retained surgical gauze in the abdomen by laparoscopy has already been described in medicine. However, a laparoscopic approach for treating a fistulous draining tract due to a gossypiboma has not been previously reported in dogs. Laparoscopic exploration of the fistula allowed the use of a pedicled omental flap through infected sites to control chronic infection. Laparoscopic surgery can be used to identify and treat abdominal gossypiboma in dogs, including those with chronic abdominal sinus.
Biological Potential of Products Obtained from Palm Trees of the Genus Syagrus
Authors: de Lacerda Coriolano Davi , Menezes Estevam Alves Maria Helena , Macário Ferro Cavalcanti Isabella
Published: August 2021

Medicinal plants have been used for centuries by communities worldwide, as they have diverse biological properties and are effective against numerous diseases. The genus Syagrus stands out for its versatility and for so many activities presented by these palm trees, mainly due to its rich chemical and fatty acid compositions. The genus has antibacterial potential, has antibiofilm, antiparasitic, antioxidant, prebiotic, antiulcerogenic, anticholinesterase, and hypoglycemic activities, and can produce biodiesel, amid others. Among all species, Syagrus coronata and Syagrus romanzoffiana stand out, presenting the greatest number of activities and applications. The secondary metabolites obtained from these palm trees present high activity even in low concentrations and can be used against infections and chronic diseases. Furthermore, these plants have been used in some communities for years and have presented healing properties, especially in inflammatory processes. Therefore, the Syagrus genus proves to be promising, which shows a lot of therapeutic potential.
Existence and Uniqueness Results of Volterra–Fredholm Integro-Differential Equations via Caputo Fractional Derivative
Authors: Ndiaye Ameth , Mansal Fulgence
Published: August 2021

In this paper, we study a Volterra–Fredholm integro-differential equation. The considered problem involves the fractional Caputo derivatives under some conditions on the order. We prove an existence and uniqueness analytic result by application of the Banach principle. Then, another result that deals with the existence of at least one solution is delivered, and some sufficient conditions for this result are established by means of the fixed point theorem of Schaefer. Ulam stability of the solution is discussed before including an example to illustrate the results of the proposal.
Proof of Engagement: A Flexible Blockchain Consensus Mechanism
Authors: Xu Yuntao , Yang Xingyu , Zhang Jiale , Zhu Junwu , Sun Maosheng , Chen Bing
Published: August 2021

Consensus mechanism plays an important role in blockchain. At present, mainstream consensus mechanisms include proof of work (PoW), proof of stake (PoS), and delegated proof of stake (DPoS). PoW, as is widely used in virtual currency, results in significant energy consumption; PoS and DPoS are proposed to reduce energy waste caused by PoW, but their disadvantage is that they tend to create Matthew Effect (ME): “the rich get richer.” In order to balance the discourse power of new nodes and elder ones, this paper proposes a flexible consensus mechanism called proof of engagement (PoE), based on the activity and contribution of network nodes. We analyze the incentive compatibility of PoE from the perspective of mechanism design. In our simulation experiments, we tested the profit changes under PoW, PoS, and PoE. The results illustrate it is easier for new nodes to accumulate their profits under PoE than under PoW or PoS, so as to reduce the negative impacts of ME.
[Retracted] Study of Node Distribution and Density Optimization in Mobile Sensor Network 3D Space
Authors: Gu Musong , Gao Chaobang , Lyu Jingjing , Fan Wenjie , You Lei
Published: August 2021

Mobile sensor network is applied in information collection in emergencies. As the mobile sensor network in real environment is widely deployed with different height and the redundancy of the sensor node needs to be as low as possible, therefore, it is necessary to effectively deploy mobile sensor nodes in the 3D space to have reasonable layout and optimized density. To this end, we established the optimization model of mobile sensor network deployment and solved the model with chemical reaction optimization (CRO). The experimental results have shown that compared with traditional particle swarm optimization (PSO), CRO algorithm can achieve reasonable deployment more rapidly and enhance the network performance evaluation value effectively. The reasonable deployment of mobile sensor network node is very significant to information collecting, postperiod decision‐making, and rapid rescuing work in emergencies.
Efficacy and Safety of Chaihu Jia Longgu Muli Decoction in the Treatment of Poststroke Depression: A Systematic Review and Meta-Analysis
Authors: Wan Renhong , Song Ruiwen , Fan Yihua , Li Linhui , Zhang Jiangxin , Zhang Beijia , Li Xinju , Wang Shenjun
Published: August 2021

Objective. Chaihu Jia Longgu Muli decoction (CLMD) is widely used in the treatment of poststroke depression (PSD) in China. Some evidences show that it has advantages, but there lacks reliable evidence. This study aims to systematically evaluate the efficacy and safety of CLMD in the treatment of PSD. Methods. All randomized controlled trials (RCTs) of CLMD in the treatment of PSD were searched from the following databases: PubMed, Cochrane Library, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP Database, and Chinese Biomedical Literature Service System (CBM), from their inception to May 2021. Two researchers independently screened the literature, extracted the data, and evaluated the risk of bias in the included studies. Meta-analysis was performed using RevMan5.3 software. Results. A total of 13 RCTs involving 1665 patients were finally included in this study, among which 5 RCTs were oral CLMD alone versus antidepressants, and 8 RCTs were oral CLMD with antidepressants versus antidepressants. Meta-analysis results showed that oral administration of CLMD could improve Hamilton’s Depression Scale (HAMD) and the Modified Edinburgh-Scandinavian Stroke Scale (MESSS) scores, improve the Barthel index, and have a low rate of adverse reactions, but there was no significant difference in the total effective rate (p=0.21> 0.05) and the National Institute of Health Stroke Scale (NIHSS) score (p=0.47> 0.05) between the antidepressants group and the oral administration of the CLMD group. Oral CLMD combined with antidepressants could improve the total effective rate, HAMD, and MESSS score, but there was no significant difference in Barthel index (p=0.06> 0.05) and the adverse reaction rate (p=0.14> 0.05) between the two groups. Conclusion. Current evidence suggests that oral CLMD alone or with antidepressants is more effective and safer in the treatment of PSD than oral antidepressants. Due to the limitation of the quality and quantity of the included studies, more high-quality studies are needed to confirm the above conclusion.
Energy Efficiency Analysis of Wireless Sensor Networks in Precision Agriculture Economy
Authors: Zhang Bingtao , Meng Lingyan
Published: August 2021

Wireless sensor network (WSN) can play an important role during precision agriculture production to promote the growth of the agricultural economy. The application of WSN in agricultural production can achieve precision agriculture. WSN has the biggest challenge of energy efficiency. This paper proposes a model to efficiently utilize the energy of sensor nodes in precision agriculture production. The proposed model provides a comprehensive analysis of the precision agriculture. The model focuses on the characteristics of WSN and expands its application in precision agriculture. In addition, this paper also puts forward some technical prospects to provide a good reference for comprehensively and effectively improving the overall development level of precision agriculture. The paper analyzes the applicability and limitations of the existing sensor networks used for agricultural production technology. The ZigBee and Lora wireless protocols are utilized to have the best power consumption and communication in short distance and long distance. Our proposed model also suggests improvement measures for the shortcomings of existing WSN in the context of energy efficiency to provide an information platform for WSN to play a better role in agricultural production.