Effects of Differences in Mechanical Parameters of Media on Mechanical Properties and Failure Form of Composite Samples

Weiqi Wang,Yicheng Ye,Qihu Wang,Xiaoyun Liu,Zhouhao Yuan,Pengcheng Li 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.2

The deformation and failure of composite rock masses at the contact zone can cause serious safety hazards in underground engineering. Therefore, uniaxial compression experiment and numerical studies of composite samples were conducted. Combined with theoretical analysis, the effects of differences in the mechanical properties of two media on the mechanical properties and failure form of composite samples were investigated. The results show that the difference in mechanical properties of two media weakened the strength and elastic modulus of the composite sample and resulted in complex failure form of the sample. Additionally, the peaks of the AE frequencies of the two media occurred successively after the peak stress of the sample. At the macrolevel, the two media failed successively. These effects are more pronounced as the degree of difference in the mechanical properties of the two media increased. The difference in mechanical properties of the two media resulted in uncoordinated deformation and constrained stress near the contact interface, and the difference in Poisson's ratio is the main factor. The influence (enhanced or weakened) of uncoordinated deformation on the mechanical properties of the composite sample is affected by differences in the elastic modulus and Poisson's ratios of the two media.

Investigating the Research Trend of Sport Management Using Social Network Analysis: Based on Journal of Sport management

( Weiqi Chai ),( Kyungsik Kim ),( Jie Li ) 한국융합과학회 2022 한국융합과학회 국제학술대회자료집 Vol.2022 No.0

At present, international sports management research and practice are in a state of many changes, so more research methods are needed to understand how sports adapt and integrate into different global environments. The study of sports management has become an important discipline in the field of international sports, and has become one of the scientific fields that many sports experts, scholars or practitioners are engaged in. It was found that although many bibliometric studies have been conducted on journals, there is a lack of research on overall research trends in journals. This study takes international sports management academic journals as the research object, and studies the research trends of EBSCO journals during 1987-2020. By searching the literature, using the time dimension of social network analysis, describing the research results in chronological order, and using logical analysis and other methods. Therefore, the social network visualization analysis method in scientometrics is used to present the evolution process of the knowledge structure and theoretical development of international sports management research, to analyze the research hotspots and development trends of international sports management as a whole, and to analyze sports in sports. utility in social phenomena. The research questions of this paper are 1. To analyze the periodical changes in the field of sports management research 2. To study the research trends or knowledge structure of sports management in the past 40 years. 3. Explore 40 years of sub-fields of study in sports management. Methods The data was organized through Excel and semantic networking analysis was performed through a python program. First, we downloaded the bibliographic information of sports management literature from EBSCO. The bibliographic information provided the title, author, periodical, publication year and English abstract, and then performed frequency analysis and centrality analysis on sports management journals in the past 40 years to study the main key factors in each period. word change. At the same time, keyword frequency analysis, centrality analysis and cohesion cluster analysis are carried out. Frequency Analysis Helps to Understand the Research Process (Ding, 2001) Simultaneous keyword frequency analysis helps to understand which keyword pairs co-occur in this paper. If the frequency of concurrent keywords is high, the correlation between keywords is high. Findings and Discussions The research results are as follows. First, sports management trends derived from keyword network analysis do not change significantly over time. However, it is worth noting that since the 2010s, the use of keywords such as consumer, fan, etc. in the field of sports management has increased. Second, centrality analysis shows that sport, management in the 1980s, sport, management in the 1990s, sport, management in the 2000s, and sport, athlete in the 2010s. Keywords are a central concept in sports management. Core keywords have high influence in sub-research fields. Third, according to the results of analyzing the sub-research areas of the cohesion group survey, sports management includes five sub-research areas. The first domain focuses on development programs, the second domain on events, the third domain on sports, the fourth domain on teams, and the fifth domain on program planning. Through the above research methods and results, the following conclusions can be drawn. The sports management research with a long history of nearly 40 years shows that a certain number of keywords contribute to the development of the knowledge structure of sports management (Barabasi, 2002).

Improvement in the Quality of Kimchi by Fermentation with Leuconostoc mesenteroides ATCC 8293 as Starter Culture

( Ling Li ),( Yu Yan ),( Weiqi Ding ),( Jinyan Gong ),( Gongnian Xiao ) 한국미생물생명공학회(구 한국산업미생물학회) 2020 한국미생물·생명공학회지 Vol.48 No.4

To investigate the effect of the predominant microorganisms in kimchi on quality, Leuconostoc mesenteroides ATCC 8293 was used as starter culture during kimchi fermentation. A higher number of lactic acid bacteria and lower initial pH were observed in starter kimchi than in non-starter kimchi in the early stage of fermentation. The concentrations of the main metabolite, lactic acid, were 69.88 mM and 83.85 mM for the non-starter and starter fermented kimchi, respectively. The free sugar concentrations of starter kimchi decreased earlier than those of non-starter kimchi, and the levels of free sugars in both kimchi samples decreased during fermentation. At the end of fermentation, non-starter kimchi had a softer texture than starter kimchi, suggesting that L. mesenteroides is useful in extending shelf life. Sensory evaluation showed that starter kimchi had higher sourness and lower bitterness and astringency values, resulting in high sensory quality. These results suggest that the L. mesenteroides ATCC 8293 strain could be a potential starter culture in kimchi.

A Social Network Analysis of Ski Research Topics in China

( Mingliang Zhang ),( Weiqi Chai ),( Wangda Guo ),( Bin Li ) 아시아스포츠융합과학회 2020 Asia Pacific Journal of Applied Sport Sciences Vol.1 No.3

PURPOSE The purposes of this paper were to: (1) study the development process of skiing knowledge network and to understand the research focus and development trend of skiing in different periods, and (2) to analyze the sub areas of ski cohesion research. METHOD Using CiteSpace visualization software of bibliometrics, a social network analysis was conducted on a total of 325 papers on 14 sports professional core journals in China Knowledge Network (CNKI) from 1990 to 2019. RESULT The research results showed that the amount of articles on skiing topics has been increased rapidly and the ski research themes change over time. In last 10 years, the main focuses of the research were Winter Olympics, ski tourism, ski industry, freestyle skiing aerials and competitive sports. The Winter Olympics, ice and snow sports and ski industry are the current and future hot research topics and frontiers. The knowledge structure consists of eight theme fields, including Winter Olympics, ski resorts, ice and snow sports, ice and snow industry, ski tourism, sports management, freestyle skiing aerials and snowboarding u-track skiing. CONCLUSION First of all, in the past 30 years, keywords in the field of ski research have undergone great changes. The Winter Olympics and ski industry topics are the current and future key research trends. In-depth research on these two topics will be an important challenge for scholars. Secondly, keyword network analysis provides new ideas and research methods for exploring the structure and development trend of the skiing field.

ShcD interacts with TrkB via its PTB and SH2 domains and regulates BDNF-induced MAPK activation

( Yuangang You ),( Weiqi Li ),( Yanhua Gong ),( Bin Yin ),( Boqin Qiang ),( Jiangang Yuan ),( Xiaozhong Peng ) 생화학분자생물학회 (구 한국생화학분자생물학회) 2010 BMB Reports Vol.43 No.7

Neurotrophins regulate many aspects of neuronal function through activation of the high affinity Trk receptors. Shc family proteins are implicated in the coupling of RTK to the Ras/mitogen- activated protein kinase signaling cascade. Here we report that the fourth Shc family member, ShcD, associates with TrkB receptor and regulates BDNF-induced MAPK activation. Yeast two-hybrid assay and Co-IP experiments demonstrate ShcD interacts with TrkB in a kinase-activity-dependent manner. Confocal analysis shows ShcD cololizes well with TrkB in transfected 293T cells. Subsequent mapping experiments and mutational analysis indicate that both PTB and SH2 domains are capable of binding to TrkB and PTB domain binds to TrkB NPQY motif. Furthermore, ShcD is involved in BDNF-induced MAPK activation. In summary, we demonstrate that ShcD is a substrate of TrkB and mediates TrkB downstream signaling pathway. [BMB reports 2010; 43(7): 485-490]

Efficient Pairwise Document Similarity Computation in Big Datasets

Papias Niyigena,Zhang Zuping,Weiqi Li,Jun Long 보안공학연구지원센터 2015 International Journal of Database Theory and Appli Vol.8 No.4

Document similarity is a common task to a variety of problems such as clustering, unsupervised learning and text retrieval. It has been seen that document with the very similar content provides little or no new information to the user. This work tackles this problem focusing on detecting near duplicates documents in large corpora. In this paper, we are presenting a new method to compute pairwise document similarity in a corpus which will reduce the time execution and save space execution resources. Our method group shingles of all documents of a corpus in a relation, with an advantage of efficiently manage up to millions of records and ease counting and aggregating. Three algorithms are introduced to reduce the candidates shingles to be compared: one creates the relation of shingles to be considered, the second one creates the set of triples and the third one gives the similarity of documents by efficiently counting the shared shingles between documents. The experiment results show that our method reduces the number of candidates pairs to be compared from which reduce also the execution time and space compared with existing algorithms which consider the computation of all pairs candidates.

Efficient fluorescent white organic light-emitting devices with a reduced efficiency roll-off based on a blue ambipolar fluorescent emitter

Tianyu Zhang,Tong Li,Wei Hu,Weiqi Wang,Letian Zhang,Wenfa Xie 한국물리학회 2014 Current Applied Physics Vol.14 No.5

White organic light-emitting devices (WOLEDs) with fluorescent donor-acceptor-substituted spirobifluorene compounds (red 2-diphenylamino-7-(2,2-dicyanovinyl)-9,90-spirobifluorene and blue 2- diphenylamino-7-(2,2-diphenylvinyl)-9,90-spirobifluorene) have been fabricated. The optimized WOLEDs shows a maximum current efficiency 5.9 cd/A and very low efficiency roll-off. From the brightness at maximum current efficiency to high brightness of 10000 cd/m2, the current efficiency rolloff is only 0.4%. It can be attributed to the ambipolar blue fluorescent emitter with voltage-independnet mobility which makes the device having a broader charge recombination zone and balance of carrier transport.

Investigation on cavitating flow and parameter effects in a control valve with a perforated cage

Wang, Hong,Zhu, Zhimao,Zhang, Miao,Li, Jie,Huo, Weiqi Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.8

Valve is widely used in the various industry areas to adjust and control the flow. Cavitation frequently takes place and sometimes is inevitable in various types of valve to cause the erosion damage. Therefore, how to control and minimize the effect of cavitation is still an important topic. This study numerically investigates the cavitating flow in a control valve with a perforated cage. The effects of some parameters on the cavitation are discussed. It also discusses to use the throttling steps to govern the cavitating flow. The results show that the opening degree of valve and the length of downstream divergent connection both influence the cavitation. The increase of the divergent length reinforces the cavitation. And the larger the opening of valve is, the intenser the cavitation is and the more vapor is present. The more throttling steps are helpful to decrease the cavitation.

Near Duplicate Document Detection using Document Image

Gaudence Uwamahoro,Zhang Zuping,Ambele Robert Mtafya,Weiqi Li,Long Jun 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.7

With development, access of Internet has allowed storage of huge documents containing information. Identifying near duplicate documents among those documents is a major problem in information retrieval due to their dimensionality which leads to high cost time. We propose an algorithm based on tf-idf method with importance and discriminative power of a term within a single document to speed up search process for detecting how documents are similar in collection. Using only 26.6% of original document size, our method performs well on efficiency and memory usage as we have reduced compare to the original one and that leads to a decreased time in searching process for similar documents in a collection.

Pectolinarigenin ameliorated airway inflammation and airway remodeling to exhibit antitussive effect

He Quan,Liu Weihua,Ma Xiaomei,Li Hongxiu,Feng Weiqi,Lu Xuzhi,Li Ying,Chen Zi 대한약리학회 2024 The Korean Journal of Physiology & Pharmacology Vol.28 No.3

Cough is a common symptom of several respiratory diseases. However, frequent coughing from acute to chronic often causes great pain to patients. It may turn into cough variant asthma, which seriously affects people's quality of life. For cough treatment, it is dominated by over-the-counter antitussive drugs, such as asmeton, but most currently available antitussive drugs have serious side effects. Thus, there is a great need for the development of new drugs with potent cough suppressant. BALB/c mice were used to construct mice model with cough to investigate the pharmacological effects of pectolinarigenin (PEC). Hematoxylin-eosin and Masson staining were used to assess lung injury and airway remodeling, and ELISA was used to assess the level of inflammatory factor release. In addition, inflammatory cell counts were measured to assess airway inflammation. Airway hyperresponsiveness assay was used to assess respiratory resistance in mice. Finally, we used Western blotting to explore the potential mechanisms of PEC. We found that PEC could alleviate lung tissue injury and reduce the release of inflammatory factors, inhibit of cough frequency and airway wall collagen deposition in mice model with cough. Meanwhile, PEC inhibited the Ras/ERK/c-Fos pathway to exhibit antitussive effect. Therefore, PEC may be a potential drug for cough suppression.