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Research on the path of effective management of participation in joint-venture railway companies by China railway group
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作者 Shaoni Zhou Zhitian Zhou Chenxia Kang 《Railway Sciences》 2024年第4期530-539,共10页
Purpose-Following the regional restructuring,the number of joint-venture railway companies in which the Group participates has significantly increased.This paper aims to explore the challenges faced by China Railway G... Purpose-Following the regional restructuring,the number of joint-venture railway companies in which the Group participates has significantly increased.This paper aims to explore the challenges faced by China Railway Group in managing participation in joint-venture railway companies.The study seeks to propose specific approaches to ensure the effective management of these companies,thereby maximizing the benefits of the regional restructuring and supporting the development of a strong transportation country and a modern infrastructure system.Design/methodology/approach-Based on the change in the shareholding relationship between China Railway Group and the joint-venture railway companies,and considering the current situation of the regional restructuring of these companies,as well as the insights from existing literature and typical case studies,this paper proposes some specific paths for effective management of joint-stock railway companies which China Railway Group participated in.Findings-The problems in participation management are the unclear dual leadership role of the party committee,the lack of discourse power,the lack of synergy between shareholders,the increasing risk of sustainable operation of the loss-making companies and the role of dispatched personnel is not fully played.Based on the theories,combined with the existing research and practical cases,the paper proposed specific approaches,such as perfecting top-level system design,maintaining the discourse power,carrying out differentiated management,arranging personnel rationally,arranging shareholders synergy,and innovating methods to provide references for China Railway Group’s subsequent management of joint venture railway companies.Originality/value-This paper contributes to the existing literature by providing a comprehensive analysis of the challenges faced by China Railway Group in managing participation in joint-venture railway companies following the regional restructuring.The study offers novel insights and practical recommendations for addressing these challenges.The findings can serve as valuable references for China Railway Group’s subsequent management of joint-venture railway companies which participated in,as well as for other stateowned enterprises facing similar challenges in managing their joint ventures. 展开更多
关键词 China railway group Joint venture railway companies Participated relationship Effective management
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Genetic mechanism of body size variation in groupers:Insights from phylotranscriptomics
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作者 Wei-Wei Zhang Zhuo-Ying Weng +5 位作者 Xi Wang Yang Yang Duo Li Le Wang Xiao-Chun Liu Zi-Ning Meng 《Zoological Research》 SCIE CSCD 2024年第2期314-328,共15页
Animal body size variation is of particular interest in evolutionary biology,but the genetic basis remains largely unknown.Previous studies have shown the presence of two parallel evolutionary genetic clusters within ... Animal body size variation is of particular interest in evolutionary biology,but the genetic basis remains largely unknown.Previous studies have shown the presence of two parallel evolutionary genetic clusters within the fish genus Epinephelus with evident divergence in body size,providing an excellent opportunity to investigate the genetic basis of body size variation in vertebrates.Herein,we performed phylotranscriptomic analysis and reconstructed the phylogeny of 13 epinephelids originating from the South China Sea.Two genetic clades with an estimated divergence time of approximately 15.4 million years ago were correlated with large and small body size,respectively.A total of 180 rapidly evolving genes and two positively selected genes were identified between the two groups.Functional enrichment analyses of these candidate genes revealed distinct enrichment categories between the two groups.These pathways and genes may play important roles in body size variation in groupers through complex regulatory networks.Based on our results,we speculate that the ancestors of the two divergent groups of groupers may have adapted to different environments through habitat selection,leading to genetic variations in metabolic patterns,organ development,and lifespan,resulting in body size divergence between the two locally adapted populations.These findings provide important insights into the genetic mechanisms underlying body size variation in groupers and species differentiation. 展开更多
关键词 Phylotranscriptomics GROUPER Body size Rapidly evolving genes(REGs) Positively selected genes(PSGs)
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Multi-aspect analysis of ureteral access sheath usage in retrograde intrarenal surgery: A RIRSearch group study
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作者 Oktay Özman Hacı M.Akgül +5 位作者 Cem Başataç Önder Çınar Eyüp B.Sancak Cenk M.Yazıcı Bülent Önal Haluk Akpınar 《Asian Journal of Urology》 CSCD 2024年第1期80-85,共6页
Objective:To evaluate the effect of ureteral access sheath(UAS)use and calibration change on stone-free rate and complications of retrograde intrarenal surgery(RIRS).Methods:Data from 568 patients undergoing RIRS for ... Objective:To evaluate the effect of ureteral access sheath(UAS)use and calibration change on stone-free rate and complications of retrograde intrarenal surgery(RIRS).Methods:Data from 568 patients undergoing RIRS for kidney or upper ureteral stones were retrospectively included.Firstly,patients were compared after 1:1 propensity score matching,according to UAS usage during RIRS(UAS used[+]87 and UAS non-used[−]87 patients).Then all UAS+patients(n=481)were subdivided according to UAS calibration:9.5-11.5 Fr,10-12 Fr,11-13 Fr,and 13-15 Fr.Primary outcomes of the study were the success and complications of RIRS.Results:Stone-free rate of UAS+patients(86.2%)was significantly higher than UAS−patients(70.1%)after propensity score matching(p=0.01).Stone-free rate increased with higher caliber UAS(9.5-11.5 Fr:66.7%;10-12 Fr:87.0%;11-13 Fr:90.6%;13-15 Fr:100%;p<0.001).Postoperative complications of UAS+patients(11.5%)were significantly lower than UAS−patients(27.6%)(p=0.01).Complications(8.7%)with 9.5-11.5 Fr UAS was lower than thicker UAS(17.2%)but was not statistically significant(p=0.09).UAS usage was an independent factor predicting stone-free status or peri-and post-operative complications(odds ratio[OR]3.654,95%confidence interval[CI]1.314-10.162;OR 4.443,95%CI 1.350-14.552;OR 4.107,95%CI 1.366-12.344,respectively).Conclusion:Use of UAS in RIRS may increase stone-free rates,which also increase with higher caliber UAS.UAS usage may reduce complications;however,complications seemingly increase with higher UAS calibration. 展开更多
关键词 STONE Retrograde intrarenal surgery Ureteral access sheath UROLITHIASIS Kidney
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Research and Design of Consistent Project Cases for the Software Engineering Course Group
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作者 Junwei Du Guozhu Liu +3 位作者 Quan Liu Xinglu Ma Meijiao Xu Wenfeng Liu 《计算机教育》 2023年第12期94-105,共12页
In order to enhance the abilities of practical innovation and solving complex engineering problems of students in the engineering context,we design a course cluster teaching model based on a unified enterprise-level p... In order to enhance the abilities of practical innovation and solving complex engineering problems of students in the engineering context,we design a course cluster teaching model based on a unified enterprise-level project case.The program divides the knowledge points required by the project into the corresponding courses,and divides their realization into the practical teaching cases,so as to realize the design of teaching practice cases embodied in the unified project framework.This model allows students to practice projects based on the unified project background while learning knowledge from different courses.It not only allows students to learn abstract,fragmented,and difficult-to-understand knowledge systems thoroughly,but also integrates the knowledge into the practice of the enterprise-level project development,helping students experience the value of knowledge in complex engineering projects and thus improving their ability to solve complex engineering problems while learning theoretical knowledge. 展开更多
关键词 Software engineering Course group Course training Comprehensive project cases School-enterprise cooperation
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Superior electrocatalytic negative electrode with tailored nitrogen functional group for vanadium redox flow battery
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作者 Min Gu Kang Wook Ahn +7 位作者 Joonhee Kang Shin Ae Song Kiyoung Kim Ju Young Woo Yong-Cheol Jeong Bonwook Koo Dae Soo Jung Sung Nam Lim 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第3期148-157,I0005,共11页
Development of electrodes with high electrocatalytic activity and stability is essential for solving problems that still restrict the extensive application of vanadium redox flow batteries(VRFBs).Here,we designed a no... Development of electrodes with high electrocatalytic activity and stability is essential for solving problems that still restrict the extensive application of vanadium redox flow batteries(VRFBs).Here,we designed a novel negative electrode with superior electrocatalytic activity by tailoring nitrogen functional groups,such as newly formed nitro and pyridinic-N transformed to pyridonic-N,from the prenitrogen-doped electrode.It was experimentally confirmed that an electrode with pyridonic-N and nitro fuctional groups(tailored nitrogen-doped graphite felt,TNGF) has superior electrocatalytic acivity with enhanced electron and mass transfer.Density functional theory calulations demonstrated the pyridonic-N and nitro functional groups promoted the adsorption,charge transfer,and bond formation with the vanadium species,which is consistent with expermental results.In addition,the V2+/V3+redox reaction mechanism on pyridonic-N and nitro functional groups was estabilised based on density functional theory(DFT) results.When TNGF was applied to a VRFB,it enabled enhanced-electrolyte utilization and energy efficiencies(EE) of 57.9% and 64.6%,respectively,at a current density of 250 mA cm^(-2).These results are 18.6% and 8.9% higher than those of VRFB with electrode containing graphitic-N and pyridinicN groups.Interestingly,TNGF-based VRFB still operated with an EE of 59% at a high current density of300 mA cm^(-2).The TNGF-based VRFB exhibited stable cycling performance without noticeable decay of EE over 450 charge-discharge cycles at a current density of 250 mA cm^(-2).The results of this study suggest that introducing pyridonic-N and nitro groups on the electrode is effective for improving the electrochemical performance of VRFBs. 展开更多
关键词 Tailored nitrogen functional group Pyridonic-N NITRO Negative electrode Density functional theory Vanadium redoxflow batteries
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Molecular evidence and phylogenetic delineation of spotted fever group Rickettsia species in Amblyomma ticks from cattle in Gauteng and Limpopo Provinces,South Africa
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作者 Keneilwe Mhlambo Benson C Iweriebor +2 位作者 Nqobile Mkolo K O Afolabi Larry C Obi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第8期371-378,共8页
Objective:To determine the prevalence of tick-borne pathogens with a particular focus on Rickettsia spp.in ticks collected from cattle in Gauteng and Limpopo Provinces,South Africa.Methods:A total of 200 ticks were co... Objective:To determine the prevalence of tick-borne pathogens with a particular focus on Rickettsia spp.in ticks collected from cattle in Gauteng and Limpopo Provinces,South Africa.Methods:A total of 200 ticks were collected from cattle within the Madala livestock,Pretoria,Gauteng Province and in Mankweng Township,Polokwane,Limpopo Province in 2019.The ticks were morphologically identified and processed individually for a total genomic DNA extraction.Specific primers targetting ompA,ompB,and the 17KDa genes were used for a molecular screening and delineation of Rickettsia from the extracted genetic materials using polymerase chain reaction(PCR)technique.PCR amplicons of positive samples were sequenced bidirectionally using the Sanger sequencing method.Sequences generated were processed and analysed using appropriate bioinformatics software.Results:The ticks were morphologically identified as Amblyomma spp.PCR profiling of the genomic DNA samples revealed the presence of the Rickettsia pathogen in 42(21%)of the ticks collected from both Provinces.Out of the genes profiled,14(7%)were positive for 17KDa,42(21%)for ompA and 32(16%)were positive for ompB genes respectively.The nucleotide blast of the sequenced genomes showed high similarity,as high as 100% with other reference Rickettsia(R.)africae in the GenBank.The phylogenetic analysis of the sequences further validated them as R.africae with their characteristic clustering pattern with related reference sequences.Conclusions:There is an abundance of R.africae in Amblyomma ticks collected from cattle in the study areas.This has serious public health implications as individuals who accidentally get infested with the ticks could acquire R.africae.Hence,adequate precautions in terms of sensitization of farmers about the risk and mass mobilization drive to control the vectors in the areas are highly recommended to safeguard public health. 展开更多
关键词 Amblyomma ticks Tick-borne pathogen RICKETTSIA CATTLE South Africa
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VANET Security through Group Broadcast Encryption
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作者 Eric Eduardo Bunese Eduardo Todt Luiz Carlos Pessoa Albini 《Journal of Computer and Communications》 2020年第8期22-35,共14页
VANET security is an evolving topic in mobile networks, as providing a secure layer of communications in such a dynamic and fast network is a challenge. The work presented in this article was conducted in order to ver... VANET security is an evolving topic in mobile networks, as providing a secure layer of communications in such a dynamic and fast network is a challenge. The work presented in this article was conducted in order to verify and evaluate the feasibility of applying group broadcast cryptography to the VANET environment, as an attempt to gain performance by decreasing the number of messages in the wireless network. Group broadcast is a symmetric/asymmetric hybrid cryptography method, aiming to merge the best of the two approaches without their major drawbacks. Simulations were set-up and run using the ONE simulator, comparing the usage of the three different cryptography approaches for VANETs. Results consider the number of connections, the number messages and the number of revocation messages per day. The resulting data promises that group broadcast encryption can be used to simplify the encrypting phase, reduce required storage and significantly decrease the number of messages in the network. 展开更多
关键词 VANET Security Group Broadcast Encryption Group Based VANET
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Finite Groups Whose Some Subgroups Are S-seminormal
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作者 王坤仁 《Northeastern Mathematical Journal》 CSCD 2004年第2期217-224,共8页
A subgroup H is called S-seminormal in a finite group G if H permutes with all Sylow p-subgroups of G with (p, |H| =1. The main object of this paper is to generalize some known results about finite supersolvable group... A subgroup H is called S-seminormal in a finite group G if H permutes with all Sylow p-subgroups of G with (p, |H| =1. The main object of this paper is to generalize some known results about finite supersolvable groups to a saturated formation containing the class of finite supersolvable groups. 展开更多
关键词 saturated formation generalized Fitting subgroup S-seminormal subgroup
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A Sufficient Condition for Mi-groups
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作者 何立国 朱刚 《Northeastern Mathematical Journal》 CSCD 2003年第4期371-374,共4页
In this note, we give a sufficient condition for Mi-group. In particular, we show that if a finite group G is the semidirect product of two subgroups with coprime orders, in which one is a Sylow tower group and its Sy... In this note, we give a sufficient condition for Mi-group. In particular, we show that if a finite group G is the semidirect product of two subgroups with coprime orders, in which one is a Sylow tower group and its Sylow subgroups are all abelian, and the other is an Mi-group and all of its proper subgroups are also Mi-groups, then G is an Mi-group. 展开更多
关键词 solvable group Mi-group semidirect product
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Molecular characterization of VP4,VP6,VP7 and NSP4 genes of group B rotavirus strains from outbreaks of gastroenteritis 被引量:1
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作者 Anismrita Lahon Shobha D Chitambar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第11期846-849,共4页
Objective:To characterize VP4,VP6,VP7 and NSP4 genes of representative GBR strains(NIV- 005625.MV-04622 and NIV-094456) delected as the major eliolngic agenl in the outbreaks of gastroenteritis in western India.Method... Objective:To characterize VP4,VP6,VP7 and NSP4 genes of representative GBR strains(NIV- 005625.MV-04622 and NIV-094456) delected as the major eliolngic agenl in the outbreaks of gastroenteritis in western India.Methods:Fecal specimens collected during the outbreaks of gastroenteritis were processed for RNA isolation.RT-PCR using GBR VP4.VP6.VP7 and NSP4 gene specific primers,nucleotide sequencing of the amplicons and phylogenetic analysis of the sequences.Results:Phylogenetic analysis of all of the VP4.VP6.VP7 and NSP4 gene sequences revealed clustering of GBR strains in Indian-Bangladeshi lineage of genotype G2 with 95.8%- 99.4%nucleotide and 97.3%-100.0%amino acid identities.However,all three strains showed the presence of unique amino acid substitutions in the VP4 protein suggesting alteration in the antigenicity of outbreak strains of GBR.The VP8* and VP5* regions of VP4 proteins showed respectively 0.5%-6.3%and 0.2%-1.1%amino acid divergence from human GBR strains of Indian-Bangladeshi lineage.Conclusions:These data confirm the reported variability of VP8* region and suggest the possible role of this region in the perpetuation of GBR infections in the environment.This is the first study to document the phylogenetic relationship of VP4,VP6.VP7 and NSP4 genes of GBR strains detected in the outbreaks of gastroenteritis from India with the CBR strains from other parts of world. 展开更多
关键词 Acute GASTROENTERITIS GROUP B ROTAVIRUS VP4 VP6 VP7 NSP4
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DYNAMIC FOR A STOCHASTIC MULTI-GROUP AIDS MODEL WITH SATURATED INCIDENCE RATE 被引量:2
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作者 韩七星 蒋达清 《Acta Mathematica Scientia》 SCIE CSCD 2020年第6期1883-1896,共14页
In this paper,a stochastic multi-group AIDS model with saturated incidence rate is studied.We prove that the system is persistent in the mean under some parametric restrictions.We also obtain the sufficient condition ... In this paper,a stochastic multi-group AIDS model with saturated incidence rate is studied.We prove that the system is persistent in the mean under some parametric restrictions.We also obtain the sufficient condition for the existence of the ergodic stationary distribution of the system by constructing a suitable Lyapunov function.Our results indicate that the existence of ergodic stationary distribution does not rely on the interior equilibrium of the corresponding deterministic system,which greatly improves upon previous results. 展开更多
关键词 multi-group AIDS model Lyapunov function stationary distribution persistence in the mean
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Weighted Parameterized Correlation Coefficients of Indeterminacy Fuzzy Multisets and Their Multicriteria Group Decision Making Method with Different Decision Risks 被引量:1
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作者 Cheng Du Jun Ye 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第10期341-354,共14页
Real-life data introduce noise,uncertainty,and imprecision to statistical projects;it is advantageous to consider strategies to overcome these information expressions and processing problems.Neutrosophic(indeterminate... Real-life data introduce noise,uncertainty,and imprecision to statistical projects;it is advantageous to consider strategies to overcome these information expressions and processing problems.Neutrosophic(indeterminate)numbers can flexibly and conveniently represent the hybrid information of the partial determinacy and partial indeterminacy in an indeterminate setting,while a fuzzy multiset is a vital mathematical tool in the expression and processing of multi-valued fuzzy information with different and/or same fuzzy values.If neutrosophic numbers are introduced into fuzzy sequences in a fuzzy multiset,the introduced neutrosophic number sequences can be constructed as the neutrosophic number multiset or indeterminate fuzzy multiset.Motivated based on the idea,this study first proposes an indeterminate fuzzy multiset,where each element in a universe set can be repeated more than once with the different and/or identical indeterminate membership values.Then,we propose the parameterized correlation coefficients of indeterminate fuzzy multisets based on the de-neutrosophication of transforming indeterminate fuzzy multisets into the parameterized fuzzy multisets by a parameter(the parameterized de-neutrosophication method).Since indeterminate decision-making issues need to be handled by an indeterminate decision-making method,a group decision-making method using the weighted parameterized correlation coefficients of indeterminate fuzzy multisets is developed along with decision makers’different decision risks(small,moderate,and large risks)so as to handle multicriteria group decision-making problems in indeterminate fuzzy multiset setting.Finally,the developed group decision-making approach is used in an example on a selection problem of slope design schemes for an open-pit mine to demonstrate its usability and flexibility in the indeterminate group decision-making problem with indeterminate fuzzy multisets. 展开更多
关键词 Indeterminate fuzzy multiset parameterized correlation coefficient multicriteria group decision making neutrosophic number slope design scheme
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Effect of PCEs with Different Functional Groups on the Performance of Cement Paste 被引量:3
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作者 何燕 ZHANG Xiong +5 位作者 WANG Yiting KONG Yaning JI Tao SHUI Liangliang WANG Xiaofu WANG Haoren 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第5期1163-1169,共7页
The adsorption behaviors and dispersing properties of polycarboxylate superplasticizer(PCE) with different functional groups were systematically analyzed to reveal the theory and methods of modifying PCE molecular str... The adsorption behaviors and dispersing properties of polycarboxylate superplasticizer(PCE) with different functional groups were systematically analyzed to reveal the theory and methods of modifying PCE molecular structures and regulating PCE performances. By substituting carboxylic groups with sulfonic groups, ester groups or acylamino groups, respectively, modified PCEs with different functional groups were synthesized. Results show that introducing low amount of ester groups or sulfonic groups into the PCE molecules has no negative effects on the fluidity of cement paste, while introducing acylamino groups into PCE molecules significantly weakens the fluidity of cement paste. At low amount(when the molar ratio of sodium methallyl sulfonate to TPEG is lower than 0.4), the rapid adsorption of sulfonic groups onto the cement particles contributes to the high dispersing performance of the sulfonic group modified PCEs. When the substitution ratio of acrylic acid by sulfonic acid is higher than 0.4, the viscosity and the yield stress of cement paste increases sharply. Redundant sulfonic groups lead to the excessive charge density of the PCE, which contributes to the inhomogeneous adsorption on the cement grains and hence results in the decline of the dispersing performance. Substitution of carboxylic group by acylamino group or ester group slightly changes the viscosity as well as the yield stress of cement paste. Introducing sulfonic group into PCE molecule improves the adsorption behavior of PCEs, while introducing ester group or acylamino group into PCE depresses the adsorption properties. 展开更多
关键词 POLYCARBOXYLATE SUPERPLASTICIZER functional group adsorption behavior RHEOLOGICAL properties CEMENT HYDRATION
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Numerical Study on the Gas Leakage and Dispersion at the Street Intersection of a Building Group 被引量:1
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作者 Weitao Zhang Mengqi Liu +2 位作者 Kaiyi Wang Fan Zhang Lei Hou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第6期1247-1266,共20页
Accidents involving natural gas leakage and dispersion pose a significant threat to human life and property.This threat is especially relevant at the street intersection at which dense buildings,heavy traffic flow,and... Accidents involving natural gas leakage and dispersion pose a significant threat to human life and property.This threat is especially relevant at the street intersection at which dense buildings,heavy traffic flow,and complex underground pipe networks meet.Scholars have conducted numerous studies on gas leakage and dispersion,but investigations of natural gas leakage and dispersion at the street intersection of a building group are not in-depth.In this paper,we presented a three-dimensional(3D)physical model based on the Computational Fluid Dynamic(CFD)methodology to study the natural gas leakage and dispersion at the street intersection of a building group.We validated the CFD methodology applied in the research based on the data from the field tests and wind tunnel experiments.Then,we simulated and analyzed the pressure,wind,and concentration of natural gas dispersion at the street intersection.The simulation results showed that vortex regions,low-pressure zones,and a building group effect could cause a build-up of natural gas concentration under perpendicular wind direction conditions.In addition,the area of hazardous region tended to increase first and then drop with the dispersion height.In the case of this study,the maximum area of hazardous region is 200 m2 located in the height of 55 m,which is the middle plane in the computational domain.The results in the paper can provide scientific references for the safe operation and emergency-management decisions of municipal gas. 展开更多
关键词 Natural gas computational fluid dynamic building group street intersection leakage and dispersion numerical simulation concentration field
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Magma Chamber Process of Post-collisional Magmatism: Insight from Textural and Elemental Characteristics of Plagioclase from the Tatun Volcanic Group, Northern Taiwan Volcanic Zone 被引量:1
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作者 ZHANG Xia GUO Kun +4 位作者 ZHANG Yu LAI Zhiqing JIANG Shulong JIANG Wenpeng LI Jingbo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第5期1587-1599,共13页
The Taiwan mountain belt, one of the youngest orogenies in the world, is caused by the collision of the Luzon arc with the Eurasian margin, which leads to post-collisional extension and magmatism in the Northern Taiwa... The Taiwan mountain belt, one of the youngest orogenies in the world, is caused by the collision of the Luzon arc with the Eurasian margin, which leads to post-collisional extension and magmatism in the Northern Taiwan Volcanic Zone(NTVZ). The magma chamber process in this region has not previously been elucidated in detail. In this paper, the textural and compositional features of plagioclase phenocrysts in basalt from the Tatun Volcanic Group(TTVG) were studied to restrict the dynamics of magma system. Results show that the magma melts in TTVG are mainly sourced from the underlying MORB-like mantle wedge but influenced by incorporation of subduction components, causing the elevated Sr/Y and Ba/Y ratios in magma melts. The subduction components are mainly transported in the form of sediment melt. The plagioclase phenocrysts in the TTVG volcanic rocks are generally coarsely core-sieved with a clear rim. The An contents in the rims of plagioclase are much lower than those of cores, and elevated FeO concentrations are detected in the plagioclase rims. We propose there exists a double-layer magma chamber in this region. The core of the plagioclase was crystalized in the deeper quiescent magma chamber(~21 km), which was subsequently partially dissolved during the ascent of magma melt under H_(2)O-undersaturated condition, forming the typical coarsely sieved texture and synneusis. When this crystal-rich melt migrates into the shallower chamber, water saturation is reached and more sodic plagioclase formed as the rim of phenocryst. Due to the considerably higher fO_(2) in the shallow chamber than in the deeper one, and the distribution of Fe between plagioclase and melt positively correlates with fO_(2), the FeO content in the plagioclase rim elevates in conjunction with increasing fO_(2). 展开更多
关键词 PLAGIOCLASE textural and compositional features dynamics of magma system Tatun Volcanic Group
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Classical Fourier Analysis over Homogeneous Spaces of Compact Groups
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作者 Arash Ghaani Farashahi 《Analysis in Theory and Applications》 CSCD 2016年第4期339-354,共16页
This paper introduces a unified operator theory approach to the abstract Fourier analysis over homogeneous spaces of compact groups. Let G be a compact group and H be a closed subgroup of G. Let G/H be the left coset ... This paper introduces a unified operator theory approach to the abstract Fourier analysis over homogeneous spaces of compact groups. Let G be a compact group and H be a closed subgroup of G. Let G/H be the left coset space of H in G and μ be the normalized G-invariant measure on G/H associated to the Weil's formula. Then, we present a generalized abstract framework of Fourier analysis for the Hilbert function space L^2 (G / H, μ). 展开更多
关键词 Compact group homogeneous space dual space Fourier transform Plancherel(trace) formula Peter-Weyl Theorem
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Improving the performance of arylamine-based hole transporting materials in perovskite solar cells: Extending π-conjugation length or increasing the number of side groups? 被引量:2
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作者 Xuepeng Liu Fantai Kong +7 位作者 Wangchao Chen Ting Yu Yin Huang Tasawar Hayat Ahmed Alsaedi Hongxia Wang Jian Chen Songyuan Dai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第5期1409-1414,共6页
In this work, we prepared three simple arylamine-based hole transporting materials from commercially available starting materials. The effect of extending z-conjugation length or increasing the number of side groups c... In this work, we prepared three simple arylamine-based hole transporting materials from commercially available starting materials. The effect of extending z-conjugation length or increasing the number of side groups compared with reference compound on the photophysical, electrochemical, hole mobility properties and performance in perovskite solar cells were further studied. It is noted that these two kinds of molecular modifications can significantly lower the HOMO level and improve the hole mobility, thus improving the hole injection from valence band of perovskite. On the other hand, the compound with more side groups showed higher hole injection efficiency due to lower HOMO level and higher hole mo- bility compared with the compound with extending π-conjugation length. The perovskite solar cells with the modified molecules as hole transporting materials showed a higher efficiency of 15.40% and 16.95%, respectively, which is better than that of the reference compound (13.18%). Moreover, the compound with increasing number of side groups based devices showed comparable photovoltaic performance with that of conventional spiro-OMeTAD (16.87%). 展开更多
关键词 Hole transporting materials PEROVSKITE π-conjugation length Side groups
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Future Development Strategies for S Group Based on SWOT Analysis
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作者 Guohui QI Ligen CHEN 《Asian Agricultural Research》 2014年第4期129-132,共4页
In recent years,the real estate development enterprises are facing the gradually increased government's macro-control,and the increasingly fierce market competition,so it is very imperative to timely adjust and ch... In recent years,the real estate development enterprises are facing the gradually increased government's macro-control,and the increasingly fierce market competition,so it is very imperative to timely adjust and change the enterprises' development strategies to adapt to the new development situation.With S Group as the study object,we use SWOT analysis to analyze the company's internal and external environment,study the current situation of the company and the existing problems,and clearly point out the opportunities and challenges facing the company.Finally we put forth some targeted strategic recommendations,in order to provide a reference for the development of S Group. 展开更多
关键词 REAL ESTATE SWOT analysis S GROUP DEVELOPMENT stra
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Could sport be part of pediatric obesity prevention and treatment? Expert conclusions from the 28th European Childhood Obesity Group Congress 被引量:3
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作者 Susanne Ring-Dimitriou Peter Krustrup +12 位作者 Manuel J Coelho-E-Silva Jorge Mota Andera Seabra Carla Rego Artur Mazur Elpis Vlachopapadopoulou Margerita Caroli Marie-Laure Frelut Eva Erhardt Anders Forslund Ema Boyland Daniel Weghuber David Thivel 《Journal of Sport and Health Science》 SCIE 2019年第4期350-352,共3页
The prevalence of pediatric obesity continues to increase worldwide,bringing with it various metabolic,functional,social,and psychological complications.1 Both the prevention and treatment of childhood obesity must be... The prevalence of pediatric obesity continues to increase worldwide,bringing with it various metabolic,functional,social,and psychological complications.1 Both the prevention and treatment of childhood obesity must be based on multidisciplinary approaches combining nutrition,physical activity(PA),and psychological support.2 As an essential element of these multicomponent strategies,regular physical activity has been acknowledged as having beneficial effects on children's and adolescents,body composition,physical fitness,and metabolic profile,as well as on their health-related quality of life,social and psychological health,and academic achievement.3,4 Given that only a relatively small proportion of children and adolescents meet the public health recommendations for PA,5 and given that weight loss exercise-based interventions suffer from a high attrition rate,there is a clear need for appropriate PAs. 展开更多
关键词 pediatric OBESITY prevention treatment 28th EUROPEAN CHILDHOOD OBESITY Group CONGRESS
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Food groups, diet quality and colorectal cancer risk in the Basque Country 被引量:3
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作者 Iker Alegria-Lertxundi Carmelo Aguirre +11 位作者 Luis Bujanda Francisco J Fernandez Francisco Polo JoseMªOrdovas MªCarmen Etxezarraga Inaki Zabalza Mikel Larzabal Isabel Portillo Marian M de Pancorbo Koldo Garcia-Etxebarria Ana MªRocandio Marta Arroyo-Izaga 《World Journal of Gastroenterology》 SCIE CAS 2020年第28期4108-4125,共18页
BACKGROUND The results obtained to date concerning food groups,diet quality and colorectal cancer(CRC)risk vary according to criteria used and the study populations.AIM To study the relationships between food groups,d... BACKGROUND The results obtained to date concerning food groups,diet quality and colorectal cancer(CRC)risk vary according to criteria used and the study populations.AIM To study the relationships between food groups,diet quality and CRC risk,in an adult population of the Basque Country(North of Spain).METHODS This observational study included 308 patients diagnosed with CRC and 308 ageand sex-matched subjects as controls.During recruitment,dietary,anthropometric,lifestyle,socioeconomic,demographic and health status information was collected.Adherence to the dietary recommendations was evaluated utilizing the Healthy Eating Index for the Spanish Diet and the MedDietScore.Conditional logistic regressions were used to evaluate the associations of food group intakes,diet quality scores,categorized in tertiles,with CRC risk.RESULTS The adjusted models for potential confounding factors showed a direct association between milk and dairy products consumption,in particular high-fat cheeses[odds ratio(OR)third tertile vs first tertile=1.87,95%confidence intervals(CI):1.11-3.16],and CRC risk.While the consumption of fiber-containing foods,especially whole grains(OR third tertile vs first tertile=0.62,95%CI:0.39-0.98),and fatty fish(OR third tertile vs first tertile=0.53,95%CI:0.27-0.99)was associated with a lower risk for CRC.Moreover,higher MD adherence was associated with a reduced CRC risk in adjusted models(OR third tertile vs first tertile=0.40,95%CI:0.20-0.80).CONCLUSION Direct associations were found for high-fat cheese,whereas an inverse relation was reported for fiber-containing foods and fatty fish,as well as adherence to a Mediterranean dietary pattern. 展开更多
关键词 Colorectal cancer Food group Dietary quality Mediterranean diet RISKFACTORS Case-control study
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