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A Study on Influencing Factors of Happiness of Urban Low-income Groups
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作者 Zhouhe Li 《Journal of Economic Science Research》 2022年第3期17-21,共5页
With the completion of the strategic vision of building a moderately prosperous society in an all-round way in 2020,China’s economic development has entered a new normal.The concept of innovative,coordinated,green,op... With the completion of the strategic vision of building a moderately prosperous society in an all-round way in 2020,China’s economic development has entered a new normal.The concept of innovative,coordinated,green,open and shared development will lead China’s economic progress and development.However,the development of urban and rural areas and regions in China is still not coordinated,and the sudden COVID-19 outbreak has caused a serious impact on urban low-income groups.Due to the characteristics of poor employment stability,low income and single source,as well as greater family pressure of urban low-income groups,the author focuses on the influencing factors of their feelings of happiness.This paper assumes that the satisfaction degree of residents’needs is positively correlated with residents’feelings of happiness.Based on Maslow’s hierarchy of needs theory,this paper analyzes the factors that may affect the happiness of urban low-income groups in five levels,and explores the special needs and difficulties of urban low-income groups in the context of the epidemic.So as to find ways to improve the happiness of urban low-income people to provide reference. 展开更多
关键词 CITY low-income groups HAPPINESS Factors affecting the introduction
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Introducing hydroxyl groups to tailor the d-band center of Ir atom through side anchoring for boosted ORR and HER
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作者 Qing Lv Meiping Li +3 位作者 Xiaodong Li Xingru Yan Zhufeng Hou Changshui Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期144-151,I0005,共9页
Tuning the coordination atoms of central metal is an effective means to improve the electrocatalytic activity of atomic catalysts.Herein,iridium(Ir) is proposed to be asymmetrically anchored by sp-N and pyridinic N of... Tuning the coordination atoms of central metal is an effective means to improve the electrocatalytic activity of atomic catalysts.Herein,iridium(Ir) is proposed to be asymmetrically anchored by sp-N and pyridinic N of hydrogen-substituted graphdiyne(HsGDY),and coordinated with OH as an Ir atomic catalyst(Ir_(1)-N-HsGDY).The electron structures,especially the d-band center of Ir atom,are optimized by these specific coordination atoms.Thus,the as-synthesized Ir_(1)-N-HsGDY exhibits excellent electrocatalytic performances for oxygen reduction and hydrogen evolution reactions in both acidic and alkaline media.Benefiting from the unique structure of HsGDY,IrN_(2)(OH)_(3) has been developed and demonstrated to act as the active site in these electrochemical reactions.All those indicate the fresh role of the sp-N in graphdiyne in producing a new anchor way and contributing to promote the electrocatalytic activity,showing a new strategy to design novel electrochemical catalysts. 展开更多
关键词 Oxygen reduction reaction D-band center Graphdiyne Hydroxyl group ELECTROCATALYSIS
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Epidemiological, Clinical Aspects and Outcome of Measles in a Low-Income Country in 2023
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作者 Sime Tchouamo Arielle Annick Enyama Dominique +7 位作者 Noukeu Diomède Atyam Ekotto Marie Christine Abouame Palma Haoua Epee Ngoue Jeannette Kago Tague Daniel Armand Touka Eric Brice Tasse Simo Nathalie Ines Nguéfack Félicité 《Open Journal of Pediatrics》 2024年第1期139-148,共10页
Introduction: Measles remains a worrying health problem in sub-Saharan African countries. There have been measles outbreaks in Cameroon with the most recent occurring between October 2022 and September 2023. The Centr... Introduction: Measles remains a worrying health problem in sub-Saharan African countries. There have been measles outbreaks in Cameroon with the most recent occurring between October 2022 and September 2023. The Centre region of Cameroon was the most affected in the country and being at the frontline of the fight against this illness, we conducted this study in order to determine the epidemiological and clinical characteristics as well as the outcome of children who contracted the measles and were hospitalized at the Yaoundé Gynaeco-Obstetric and Pediatric Hospital. Methodology: We conducted a cross-sectional descriptive and prospective study for one year from October 2022 to November 2023 corresponding to the duration of the outbreak. We included all children admitted in the pediatric unit for measles and its complications during this period. Results: In total, 60 children were enrolled. Their caregivers were mostly their mothers who had a mean age of 34.71 ± 9.55 years living in significant precarious conditions for the majority. The median age of children was 16 months (09 - 30 months). Twenty six percent of children (16) were less than 9 months. Girls were predominant (55%). Most children were not up to date with their routine EPI vaccination (80%) and most did not receive the measles and Rubella vaccine (76.67%). Clinical manifestations, included fever, conjunctivitis, and cough. Skin rash and catarrh (98.33% and 86.67% respectively) are the case definition signs of measles. The outcome was unfavorable for 4 children. One had a neurological disorder: coma and three presented with pneumonia and severe respiratory distress (6.67%). Conclusion: Measles is still being a reality and claiming lives in our context, emphasis should be made on immunization coverage and if possible, advocacies should be formulated to decrease the age of measles vaccine administration. 展开更多
关键词 MEASLES COMPLICATIONS low-income Countries
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A Novel On-Site-Real-Time Method for Identifying Characteristic Parameters Using Ultrasonic Echo Groups and Neural Network
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作者 Shuyong Duan Jialin Zhang +2 位作者 Heng Ouyang Xu Han Guirong Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期215-228,共14页
On-site and real-time non-destructive measurement of elastic constants for materials of a component in a in-service structure is a challenge due to structural complexities,such as ambiguous boundary,variable thickness... On-site and real-time non-destructive measurement of elastic constants for materials of a component in a in-service structure is a challenge due to structural complexities,such as ambiguous boundary,variable thickness,nonuniform material properties.This work develops for the first time a method that uses ultrasound echo groups and artificial neural network(ANN)for reliable on-site real-time identification of material parameters.The use of echo groups allows the use of lower frequencies,and hence more accommodative to structural complexity.To train the ANNs,a numerical model is established that is capable of computing the waveform of ultrasonic echo groups for any given set of material properties of a given structure.The waveform of an ultrasonic echo groups at an interest location on the surface the structure with material parameters varying in a predefined range are then computed using the numerical model.This results in a set of dataset for training the ANN model.Once the ANN is trained,the material parameters can be identified simultaneously using the actual measured echo waveform as input to the ANN.Intensive tests have been conducted both numerically and experimentally to evaluate the effectiveness and accuracy of the currently proposed method.The results show that the maximum identification error of numerical example is less than 2%,and the maximum identification error of experimental test is less than 7%.Compared with currently prevailing methods and equipment,the proposefy the density and thickness,in addition to the elastic constants.Moreover,the reliability and accuracy of inverse prediction is significantly improved.Thus,it has broad applications and enables real-time field measurements,which has not been fulfilled by any other available methods or equipment. 展开更多
关键词 Parameter identification Ultrasonic echo group High-precision modeling Artificial neural network NDT
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How Group Leaders Build Stable Community Buying Groups:A Perspective Based on the Differential Mode of Association
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作者 SI Xiang 《Psychology Research》 2024年第1期30-35,共6页
Since 2016,community group buying has grown significantly in China,largely driven by its efficient logistics,supply chains,low prices,and convenience.This model has been further popularized during the COVID-19 pandemi... Since 2016,community group buying has grown significantly in China,largely driven by its efficient logistics,supply chains,low prices,and convenience.This model has been further popularized during the COVID-19 pandemic due to its effectiveness in meeting daily needs while minimizing human-to-human contact.A key component of this business model is the“group leaders”-influential individuals within a community responsible for managing group buying activities,which include order collection,supplier liaison,and goods distribution.Their primary task is to form and sustain a reliable community group buying consortium,a task that demands excellent organizational and interpersonal skills.This paper examines this phenomenon using the lens of the differential mode of association,a theoretical model explaining interpersonal relationships in traditional Chinese society.The research indicates that group leaders,through regular interaction with consumers,are able to alter their social network position,increase their influence,understand consumer needs,provide satisfying services,and enhance trust,thereby transforming consumers into loyal group buying participants.This transformation not only brings stability to group buying activities but also reinforces the community influence of group leaders,thus fostering the growth of community group buying. 展开更多
关键词 Community group buying China group leaders The differential mode of association
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Combined Promoting Effects of Specific Organic Functional Groups and Alumina Surface Characteristics for the Design of a Highly Efficient NiMo/Al_(2)O_(3) Hydrodesulfurization Catalyst
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作者 Li Huifeng Li Mingfeng +2 位作者 Zhang Le Wang Wei Nie Hong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期1-11,共11页
To prepare a highly efficient NiMo/Al_(2)O_(3) hydrodesulfurization catalyst,the combined effects of specific organic functional groups and alumina surface characteristics were investigated.First,the correlation betwe... To prepare a highly efficient NiMo/Al_(2)O_(3) hydrodesulfurization catalyst,the combined effects of specific organic functional groups and alumina surface characteristics were investigated.First,the correlation between the surface characteristics of four different alumina and the existing Mo species states was established.It was found that the Mo equilibrium adsorption capacity can be used as a specific descriptor to quantitatively evaluate the changes in surface characteristics of different alumina.A lower Mo equilibrium adsorption capacity for alumina means weaker metal-support interaction and the loaded Mo species are easier to transform into MoS2.However,the Mo-O-Al bonds still exist at the metal-support interface.The introduction of cationic surfactant hecadecyl trimethyl ammonium bromide(CTAB)can further improve Mo species dispersion through electrostatic attraction with Mo anions and interaction of its alkyl chain with the alumina surface;meanwhile,the introduction of ethylenediamine tetraacetic acid(EDTA)can complex with Ni ions to enhance the Ni-promoting effect on Mo.Therefore,the NiMo catalyst designed using alumina with lower Mo equilibrium adsorption capacity and the simultaneous addition of EDTA and CTAB exhibits the highest hydrodesulfurization activity for 4,6-dimethyl dibenzothiophene because of its proper metal-support interaction and more well-dispersed Ni-Mo-S active phases. 展开更多
关键词 ALUMINA Mo equilibrium adsorption capacity organic functional groups metal-support interaction HYDRODESULFURIZATION
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金融机构ESG投资的“漂绿”与“反漂绿”——基于DWSGroup的案例分析
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作者 许汉友 杨雨蝶 《财会月刊》 北大核心 2024年第8期92-98,共7页
深化绿色金融发展、助力经济绿色发展,是实现“双碳”目标的重要途径,特别是在ESG理念盛行的今天,金融机构的ESG投资行为因其深远影响而颇受投资者青睐,但层出不穷的“漂绿”现象也牢牢制约着绿色金融的发展,制约着ESG投资的发展。西方... 深化绿色金融发展、助力经济绿色发展,是实现“双碳”目标的重要途径,特别是在ESG理念盛行的今天,金融机构的ESG投资行为因其深远影响而颇受投资者青睐,但层出不穷的“漂绿”现象也牢牢制约着绿色金融的发展,制约着ESG投资的发展。西方国家作为绿色金融发展先驱,从信息披露、制度监管、实践探索等方面对“漂绿”现象进行了研究和治理。本文在学习其先进经验的基础上,基于舞弊三角理论对DWSGroup案例进行分析,从压力、机会和自我合理化因素角度对金融机构ESG投资“漂绿”行为的动因进行分析,并据此提出我国“反漂绿”体系框架,以期为绿色金融的平稳发展和“双碳”目标的实现作出贡献。 展开更多
关键词 漂绿 绿色金融 DWS group ESG投资
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MXene terminating groups=O,–F or–OH,–F or=O,–OH,–F,or=O,–OH,–Cl? 被引量:2
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作者 Tariq Bashir Sara Adeeba Ismail +3 位作者 Jiaqi Wang Wenhao Zhu Jianqing Zhao Lijun Gao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期90-104,I0003,共16页
MXenes are a novel family of two-dimensional(2D)materials that are fast gaining popularity due to their versatile characteristics.The surfaces of these materials are often functionalized by negatively charged terminal... MXenes are a novel family of two-dimensional(2D)materials that are fast gaining popularity due to their versatile characteristics.The surfaces of these materials are often functionalized by negatively charged terminal groups,such as=O,OH,and F during their synthesis,and it has been hypothesized that regulating the surface terminators enables to control the material characteristics.However,there is still a large gap between computational and experimental investigations regarding comprehending the surface functional groups.Surfaces with mixed terminations are consistently synthesized in experiments,although pure terminated surfaces are predicted by computational research.Here we summarized the nature of chemical bonding in transition metal carbide materials(MXenes)by1H and19F nuclear magnetic resonance(NMR),Raman,X-ray absorption near edge structure(XANES),extended X-ray absorption fine structure(EXAFS),ultraviolet photoelectron spectroscopy(UPS),X-ray photoelectron spectroscopy(XPS)/scanning transmission electron microscopy(STEM),and thermogravimetric analysis-mass spectrometry(TGA-MS)characterizations.Previous literature reveals that=O,–OH,–F,and–Cl are typical MXene surface terminators.However,recent comparative investigations on the valence band intensity distribution in MXenes reveal that the–OH cannot be considered an intrinsic termination species in MXenes.The surface terminals(=O,–OH,–F,and–Cl)of several MXenes,particularly V2CTxand Ti3C2Tx,will be identified and quantified here.We have also discussed different etching approaches for the synthesis of MXene,the dependence of MXene conductivity on MXene terminating groups,and the emission of various gaseous products that evolved during its chemical transformations.This paper provides significance,especially in the field of energy conversion and storage materials,where the intercalation process is crucial. 展开更多
关键词 MXene surface terminating groups Characterization CONDUCTIVITY Oxidation
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Utilization of access to colorectal cancer screening modalities in low-income populations after medicaid expansion
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作者 Gerald Fletcher Joan Culpepper-Morgan +1 位作者 Alvaro Genao Eric Alatevi 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第9期1653-1661,共9页
BACKGROUND Colorectal cancer(CRC)remains a relevant public health problem.Current research suggests that racial,economic and geographic disparities impact access.Despite the expansion of Medicaid eligibility as a key ... BACKGROUND Colorectal cancer(CRC)remains a relevant public health problem.Current research suggests that racial,economic and geographic disparities impact access.Despite the expansion of Medicaid eligibility as a key component of the Affordable Care Act(ACA),there is a dearth of information on the utilization of newly gained access to CRC screening by low-income individuals.This study investigates the impact of the ACA’s Medicaid expansion on utilization of the various CRC screening modalities by low-income participants.Our working hypothesis is that Medicaid expansion will increase access and utilization of CRC screening by low-income participants.AIM To investigate the impact of the Affordable Care Act and in particular the effect of Medicaid expansion on access and utilization of CRC screening modalities by Medicaid state expansion status across the United States.METHODS This was a quasi-experimental study design using data from the Behavioral Risk Factor Surveillance System,a large health system survey for participants across the United States and with over 2.8 million responses.The period of the study was from 2011 to 2016 which was dichotomized as pre-ACA Medicaid expansion(2011-2013)and post-ACA Medicaid expansion(2014-2016).The change in utilization of access to CRC screening strategies between the expansion periods were analyzed as the dependent variables.Secondary analyses included stratification of the access by ethnicity/race,income,and education status.RESULTS A greater increase in utilization of access to CRC screening was observed in Medicaid expansion states than in nonexpansion states[+2.9%;95%confidence interval(95%CI):2.12,3.69].Low-income participants showed a+4.02%(95%CI:2.96,5.07)change between the expansion periods compared with higher income groups+3.19%(1.70,4.67).Non-Hispanic Whites and Hispanics[+3.01%(95%CI:2.16,3.85)vs+5.51%(95%CI:2.81,8.20)]showed a statistically significant increase in utilization of access but not in Non-Hispanic Blacks,or Multiracial.There was an increase in utilization across all educational levels.This was significant among those who reported having a high school graduate degree or more+4.26%(95%CI:3.16,5.35)compared to some high school or less+1.59%(95%CI:-1.37,4.55).CONCLUSION Medicaid expansion under the Affordable Care Act led to an overall increase in self-reported use of CRC screening tests by adults aged 50-64 years in the United States.This finding was consistent across all low-income populations,but not all races or levels of education. 展开更多
关键词 Medicaid expansion Colorectal cancer screening low-income DISPARITIES MINORITIES Affordable care act
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Investigation into Protective Groups for Anilino Functionality upon Oxone-Mediated Oxidative Esterification
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作者 Tomoko Mineno Takeya Yamamoto +1 位作者 Tomoya Nobuta Hisao Kansui 《International Journal of Organic Chemistry》 CAS 2023年第1期7-15,共9页
In the course of organic synthesis, particularly for multi-step synthesis or natural product total synthesis, the selection of appropriate protective groups for the intended functionality is crucial in order to achiev... In the course of organic synthesis, particularly for multi-step synthesis or natural product total synthesis, the selection of appropriate protective groups for the intended functionality is crucial in order to achieve chemoselective synthetic goals. The development of many useful protective groups has been reported based on the functionality of the anilino group. Herein, we discuss our study of various protective groups and the processes we used to establish compatibility with anilino functionality via the implementation of Oxone-mediated oxidative esterification in methanol. The results and the details of our experiments are reported herein. 展开更多
关键词 Protective groups Anilino Functionality OXONE ALDEHYDE Oxidative Esterification
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Functional groups and seasonal diversity of crustacean zooplankton in adjacent waters of Haizhou Bay,South Yellow Sea
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作者 Zeqi ZHENG Shunan FU +5 位作者 Yixuan LI Ruping GE Hongju CHEN Zhenjiang YE Yunyun ZHUANG Guangxing LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期1007-1023,共17页
Zooplankton are important linkages in the food web and can respond nonlinearly to environmental changes.Marine organisms thrive from spring to summer.Thus,it is crucial to understand how ecological functions of zoopla... Zooplankton are important linkages in the food web and can respond nonlinearly to environmental changes.Marine organisms thrive from spring to summer.Thus,it is crucial to understand how ecological functions of zooplankton communities may shift under seasonal environmental changes during this period.Samples were collected from May to August(May,June-Ⅰ,June-Ⅱ,July-Ⅰ,July-Ⅱ,and August)in 2018 in Haizhou Bay,Jiangsu,East China for zooplankton and environmental variables.Crustaceans accounted for 75 out of 134 zooplankton taxa and 91.8%of total zooplankton abundance.The average abundance of crustacean varied between 2824.6±635.4 inds./m3 in July-Ⅱand 6502.7±1008.8 inds./m3 in June-Ⅱ.Multivariate analyses results showed that the dissimilarity of community increased gradually in the time series.Body length,feeding type,trophic group,and reproduction mode were used to investigate crustacean community functions.Trait-based functional groups contained species with similar ecological roles.Functional diversity fused the differences of species and trait.The proportion of large-sized species(2-5 mm)decreased with the increasing proportion of medium-sized species(1-2 mm).The proportion of current feeders increased with the drop in the proportion of mixed feeders.Parthenogenesis species increased with decreasing free spawners,and omnivores-carnivores increased with decreasing omnivoresherbivores.Generalized additive models suggested that temperature was the main driver of variations in crustacean zooplankton function.Seven identified functional groups varied with increasing temperature.Omnivorous-herbivorous copepods declined(90.0%-68.0%),whereas the parthenogenetic cladocerans increased(0-24.1%).The small egg-brooding ambush copepods fluctuated(6.5%-9.3%)with increasing water temperature.The other functional groups changed slightly.Functional diversity also varied according to temperature changes.The community structure and ecological function of crustacean zooplankton community showed gradual changes with increasing temperature from spring to summer. 展开更多
关键词 ZOOPLANKTON TRAIT functional group DIVERSITY Yellow Sea Haizhou Bay
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Partial Groups, Simplicial K(G, 1)’s and Kan Complexes
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作者 Solomon Jekel 《Advances in Pure Mathematics》 2023年第11期725-731,共7页
In our paper Simplicial K(G, 1)’s we constructed a sub-complex of the nerve of a group G determined by a partial group structure, and we proved, under a generalized associativity condition called regularity, that the... In our paper Simplicial K(G, 1)’s we constructed a sub-complex of the nerve of a group G determined by a partial group structure, and we proved, under a generalized associativity condition called regularity, that the sub-complex realizes as a K(G, 1). This type of sub-complex appears naturally in several topological and algebraic contexts. In this note we prove that regularity of a partial group implies that the Kan extension condition is satisfied on its nerve in dimensions greater than one, and in dimension one a weaker version of the extension condition holds. 展开更多
关键词 Partial group Simplicial Set NERVE Kan Extension
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States of graphene oxide and surface functional groups amid adsorption of dyes and heavy metal ions
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作者 Zhaoyang Han Ling Sun +6 位作者 Yingying Chu Jing Wang Chenyu Wei Qianlei Jiang Changbao Han Hui Yan Xuemei Song 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第11期197-208,共12页
Water pollution regarding dyes and heavy metal ions is crucial facing the world.How to effectively separate these contaminants from water has been a key issue.Graphene oxide(GO)promises the greenwater world as a long-... Water pollution regarding dyes and heavy metal ions is crucial facing the world.How to effectively separate these contaminants from water has been a key issue.Graphene oxide(GO)promises the greenwater world as a long-lasting spotlight adsorbent material and therefore,harnessing GO has been the research hotspot for over a decade.The state of GO as well as its surface functional groups plays an important role in adsorption.And the way of preparation and structural modification matters to the performance of GO.In this review,the significance of the state of existence of stock GO and surface functional groups is explored in terms of preparation,structural modification,and adsorption.Besides,various adsorbates for GO adsorption are also involved,the discussion of which is rarely established elsewhere. 展开更多
关键词 Stock graphene oxide Surface functional groups Existence state ADSORBATES Enhanced adsorption DYES
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Interpersonal Perception in Virtual Groups: Examining Homophily, Identification and Individual Attraction Using Social Relations Model in Network
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作者 Zuoming Wang 《Social Networking》 2023年第2期45-56,共12页
With the penetration of the Internet, virtual groups have become more and more popular. The reliability and accuracy of interpersonal perception in the virtual environment is an intriguing issue. Using the Social rela... With the penetration of the Internet, virtual groups have become more and more popular. The reliability and accuracy of interpersonal perception in the virtual environment is an intriguing issue. Using the Social relations model (SRM) [1], this paper investigates interpersonal perception in virtual groups from a multilevel perspective. In particular, it examines the following three areas: homophily, identification, and individual attraction, and explores how much of these directional and dyadic relational evaluations can be attributed to the effect of the actor, the partner, and the relationship. 展开更多
关键词 Virtual groups Interpersonal Perception Social Relations Model HOMOPHILY IDENTIFICATION Individual Attraction
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ASL Recognition by the Layered Learning Model Using Clustered Groups
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作者 Jungsoo Shin Jaehee Jung 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期51-68,共18页
American Sign Language(ASL)images can be used as a communication tool by determining numbers and letters using the shape of the fingers.Particularly,ASL can have an key role in communication for hearing-impaired perso... American Sign Language(ASL)images can be used as a communication tool by determining numbers and letters using the shape of the fingers.Particularly,ASL can have an key role in communication for hearing-impaired persons and conveying information to other persons,because sign language is their only channel of expression.Representative ASL recognition methods primarily adopt images,sensors,and pose-based recognition techniques,and employ various gestures together with hand-shapes.This study briefly reviews these attempts at ASL recognition and provides an improved ASL classification model that attempts to develop a deep learning method with meta-layers.In the proposed model,the collected ASL images were clustered based on similarities in shape,and clustered group classification was first performed,followed by reclassification within the group.The experiments were conducted with various groups using different learning layers to improve the accuracy of individual image recognition.After selecting the optimized group,we proposed a meta-layered learning model with the highest recognition rate using a deep learning method of image processing.The proposed model exhibited an improved performance compared with the general classification model. 展开更多
关键词 American sign language deep learning RECOGNITION CNN ResNet clustered group
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Eff ects of stand condition and root density on fi ne-root dynamics across root functional groups in a subtropical montane forest
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作者 Lin Huang Rudong Zhao +3 位作者 Xiaoxiang Zhao Qiuxiang Tian Pengyun Yue Feng Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期665-675,共11页
Fine roots play key roles in belowground C cycling in terrestrial ecosystems.Based on their distinct functions,fi ne roots are either absorptive fi ne roots(AFRs)or transport fi ne roots(TFRs).However,the function-bas... Fine roots play key roles in belowground C cycling in terrestrial ecosystems.Based on their distinct functions,fi ne roots are either absorptive fi ne roots(AFRs)or transport fi ne roots(TFRs).However,the function-based fi ne root dynamics of trees and their responses to forest stand properties remain unclear.Here,we studied the dynamics of AFRs and TFRs and their responses to stand conditions and root density in a subtropical montane mixed forest based on a 2-a root window experiment.Mean(±SE)annual production,mortality,and turnover rate of AFRs were 7.87±0.17 m m^(−2)a^(−1),8.13±0.20 m m^(−2)a^(−1)and 2.96±0.24 a^(−1),respectively,compared with 7.09±0.17 m m^(−2)a^(−1),4.59±0.17 m m^(−2)a^(−1),and 2.01±0.22 a^(−1),respectively,for TFRs.The production and mortality of fi ne roots were signifi cantly higher in high root-density sites than in low-root density sites,whereas the turnover of fi ne roots was faster in the low root-density sites.Furthermore,root density had a larger positive eff ect than other environmental factors on TFR production but had no obvious impact on AFR production.Tree species diversity had an apparent positive eff ect on AFR production and was the crucial driver of AFR production,probably due to a complementary eff ect,but had no evident impact on TFR.Both tree density and tree species diversity were positively correlated with the mortality of AFRs and negatively related to the turnover of TFRs,suggesting that higher root density caused stronger competition for rooting space and that plants tend to reduce maintenance costs by decreasing TFR turnover.These fi ndings illustrated the importance of root functional groups in understanding root dynamics and their responses to changes in environmental conditions. 展开更多
关键词 Root functional group Root production Root mortality Root turnover Stand condition Badagongshan mountain
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Effects of non-liquefiable crust layer and superstructure mass on the response of 2×2 pile groups to liquefaction-induced lateral spreading
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作者 S.Mohsen Haeri Morteza Rajabigol +2 位作者 Saman Salaripour Hiwa Sayaf Milad Zangeneh 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第10期2701-2719,共19页
In this research,two shake table experiments were conducted to study the effects of non-liquefiable crust layer and superstructure mass on the responses of two sets of 22 pile groups to liquefactioninduced lateral spr... In this research,two shake table experiments were conducted to study the effects of non-liquefiable crust layer and superstructure mass on the responses of two sets of 22 pile groups to liquefactioninduced lateral spreading.In this regard,an inclined base layer overlain by a very loose liquefiable layer was constructed in both models;while only in one model,a non-liquefiable crust layer was built.A lumped mass,being representative of a superstructure,was attached to the cap of one pile group in both models.The models were fully instrumented with various sensors,including acceleration,displacement,and pore water pressure transducers.Also,the piles were instrumented with pair strain gauges to measure pure bending moments induced by cyclic and monotonic loadings associated with ground shaking and lateral spreading,respectively.The results showed that the existence of the non-liquefiable crust layer increases both the maximum and residual soil displacements at the free field and also the maximum bending moments in the piles.The results of the experiments indicated that the crust layer induces a high kinematic lateral soil pressure and force on the piles which are not present in the crustless case.The crust layer increases the pile cap displacement before liquefaction,albeit decreases it after liquefaction,due to the elastic rebound of the piles in the liquefiable layer.The crust layer postpones both liquefaction triggering and dissipation of excess pore water pressure.The existence of the superstructure mass on the pile caps decreases the acceleration amplitude of the pile caps,while increases their maximum displacement. 展开更多
关键词 Soil liquefaction Lateral spreading 1g shake table test Pile group Crust layer SUPERSTRUCTURE
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Efficient Expressive Attribute-Based Encryption with Keyword Search over Prime-Order Groups
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作者 Qing Miao Lan Guo +1 位作者 Yang Lu Zhongqi Wang 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期2737-2754,共18页
Attribute-based encryption with keyword search(ABEKS)is a novel cryptographic paradigm that can be used to implementfine-grained access control and retrieve ciphertexts without disclosing the sensitive information.It i... Attribute-based encryption with keyword search(ABEKS)is a novel cryptographic paradigm that can be used to implementfine-grained access control and retrieve ciphertexts without disclosing the sensitive information.It is a perfect combination of attribute-based encryption(ABE)and public key encryption with keyword search(PEKS).Nevertheless,most of the existing ABEKS schemes have limited search capabilities and only support single or simple conjunctive keyword search.Due to the weak search capability and inaccurate search results,it is difficult to apply these schemes to practical applications.In this paper,an effi-cient expressive ABEKS(EABEKS)scheme supporting unbounded keyword uni-verse over prime-order groups is designed,which supplies the expressive keyword search function supporting the logical connectives of“AND”and“OR”.The proposed scheme not only leads to low computation and communica-tion costs,but also supports unbounded keyword universe.In the standard model,the scheme is proven to be secure under the chosen keyword attack and the cho-sen plaintext attack.The comparison analysis and experimental results show that it has better performance than the existing EABEKS schemes in the storage,com-putation and communication costs. 展开更多
关键词 Searchable encryption expressive keyword search attribute-based encryption unbounded keyword universe prime-order group
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Stabilizing Buried Interface via Synergistic Effect of Fluorine and Sulfonyl Functional Groups Toward Efficient and Stable Perovskite Solar Cells
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作者 Cheng Gong Cong Zhang +4 位作者 Qixin Zhuang Haiyun Li Hua Yang Jiangzhao Chen Zhigang Zang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第2期32-45,共14页
The interfacial defects and energy barrier are main reasons for interfacial nonradiative recombination.In addition,poor perovskite crystallization and incomplete conversion of PbI_(2) to perovskite restrict further en... The interfacial defects and energy barrier are main reasons for interfacial nonradiative recombination.In addition,poor perovskite crystallization and incomplete conversion of PbI_(2) to perovskite restrict further enhancement of the photovoltaic performance of the devices using sequential deposition.Herein,a buried interface stabilization strategy that relies on the synergy of fluorine(F)and sulfonyl(S=O)functional groups is proposed.A series of potassium salts containing halide and non-halogen anions are employed to modify SnO_(2)/perovskite buried interface.Multiple chemical bonds including hydrogen bond,coordination bond and ionic bond are realized,which strengthens interfacial contact and defect passivation effect.The chemical interaction between modification molecules and perovskite along with SnO_(2) heightens incessantly as the number of S=O and F augments.The chemical interaction strength between modifiers and perovskite as well as SnO_(2) gradually increases with the increase in the number of S=O and F.The defect passivation effect is positively correlated with the chemical interaction strength.The crystallization kinetics is regulated through the compromise between chemical interaction strength and wettability of substrates.Compared with Cl−,all non-halogen anions perform better in crystallization optimization,energy band regulation and defect passivation.The device with potassium bis(fluorosulfonyl)imide achieves a tempting efficiency of 24.17%. 展开更多
关键词 Perovskite solar cells Buried interface Multiple chemical bonds Synergistic effect of functional groups Defect passivation
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Dynamical Properties of Additive Cellular Automata over Finite Abelian Groups
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作者 邓爱平 王枫杰 伍陈晨 《Journal of Donghua University(English Edition)》 CAS 2023年第1期116-121,共6页
Some dynamical properties were discussed for additive cellular automata(CA)over finite abelian groups.These properties include surjection,ergodicity,sensitivity to initial conditions and positive expansivity.Some nece... Some dynamical properties were discussed for additive cellular automata(CA)over finite abelian groups.These properties include surjection,ergodicity,sensitivity to initial conditions and positive expansivity.Some necessary and sufficient conditions of determining ergodicity and sensitivity of the above additive CA were presented,respectively.A necessary condition for the positive expansivity of the above additive CA was given.The positive expansivity was proved to be preserved under the shift mappings for the general CA.The discussion was mainly based on the structure theorem of the finite abelian groups and the matrix associated with the global rule of the additive CA over the finite abelian p-groups. 展开更多
关键词 additive cellular automaton finite abelian group ERGODICITY sensitivity to initial condition positive expansivity
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