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The Gender-Biased Employment Effect of Exports： Evidence from China

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2014年第2期9卷 261-284页

作者： Hao chen jianwei chen Institute of International Economy University of International Business and EconomicsBeijing 100029 China MOE-UIBE of Education and Economy Research University of International Business andEconomics Beijing 100029 China

Traditional international trade theories believe export trade has a positive effect on employment, which means exports would increase the level of employment with no difference between genders. Based on enterprise heterogeneity, however, the new-trade theories doubt this conclusion. Using the Chinese industrial enterprise database （2006-2009）, this paper re-examines the relationship between export volume and the level of employment, and discusses different effects of exports on the employment of different genders. We find that although exports increase the total level of employment, enterprises＇ exports have a prominent negative effect on the employment of women. This proves that it is hard to optimize employment structure through the promotion of foreign trade, even if it improves the overall level of employment.

关键词： screening-matching model enterprise heterogeneity gender differences

An Efficient and Privacy-Preserving Data Aggregation Scheme Supporting Arbitrary Statistical Functions in IoT

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China Communications 2022年第6期19卷 91-104页

作者： Haihui Liu jianwei chen Liwei Lin Ayong Ye Chuan Huang College of Computer and Cyber Security Fujian Normal UniversityFuzhou 350117China Fujian Provincial Key Laboratory of Network Security and Cryptology Fujian Normal UniversityFuzhou 350117China School of Computer Science and Mathematics Fujian University of TechnologyFuzhou 350118China Digital Fujian Institute of Big Data Security Technology Fujian Normal UniversityFuzhou 350117China

The Internet of Things(IoT)has profoundly impacted our lives and has greatly revolutionized our *** terminal devices in an IoT data aggregation application sense real-time data for the remote cloud server to achieve intelligent ***,the high frequency of collecting user data will raise people concerns about personal *** recent years,many privacy-preserving data aggregation schemes have been ***,most existing schemes cannot support either arbitrary aggregation functions,or dynamic user group management,or fault *** this paper,we propose an efficient and privacy-preserving data aggregation *** the scheme,we design a lightweight encryption method to protect the user privacy by using a ring topology and a random location *** this basis,the proposed scheme supports not only arbitrary aggregation functions,but also flexible dynamic user ***,the scheme achieves faulttolerant capabilities by utilizing a future data buffering *** analysis reveals that the scheme can achieve the desired security properties,and experimental evaluation results show the scheme's efficiency in terms of computational and communication overhead.

关键词： Internet of Things data aggregation privacy protection arbitrary aggregation functions

The preparation of nitrogen-doped TiO_2 nanocrystals with exposed {001} facets and their visible-light photocatalytic performances

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Chinese Science Bulletin 2014年第18期59卷 2199-2207页

作者： Huiying Ai Jianwen Shi jianwei chen Minglai Fu Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of Sciences

Anatase TiO2with exposed{001}facets has been deepgoingly studied for optimizing its photocatalytic *** this study,we synthesized N-doped TiO2 nanocrystals with exposed{001}facets by sol–gel method and solvothermal method,*** physical and chemical properties of as-synthesized samples,such as morphology,crystal phase,surface elements composition,porous structure,specific surface area,and optical response,were characterized in *** photocatalytic performances of all samples were evaluated by photocatalytic decoloration of methylene blue under visible-light irradiation(k[420 nm).The results showed that the as-prepared samples present high visible-light photocatalytic performances,which can be ascribed to the excellent crystallization,the enhancement of absorbance in the visible-light region,and the strong adsorption performance,and calcination treatment is helpful to further improve the visible-light photocatalytic performance of N-doped TiO2 nanocrystals with exposed{001}facets.

关键词： TiO2纳米晶光催化性能可见光照射氮掺杂晶面晶带比表面积光催化活性

Seed Selection for Data Offloading Based on Social and Interest Graphs

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Computers, Materials & Continua 2018年第12期57卷 571-587页

作者： Ying Li Jianbo Li jianwei chen Minchao Lu Caoyuan Li College of Computer Science and Technology Qingdao UniversityQingdao266071China School of Computer Beijing Institute of TechnologyBeijing100081China Faculty of Engineering and Information Technology University of Technology SydneyNSW 2006Australia

The explosive growth of mobile data demand is becoming an increasing burden on current cellular *** address this issue,we propose a solution of opportunistic data offloading for alleviating overloaded cellular *** principle behind it is to select a few important users as seeds for data *** three critical steps are detailed as *** first explore individual interests of users by the construction of user profiles,on which an interest graph is built by Gaussian graphical *** then apply the extreme value theory to threshold the encounter duration of user ***,a contact graph is generated to indicate the social relationships of ***,a contact-interest graph is developed on the basis of the social ties and individual interests of *** on different graphs,three strategies are finally proposed for seed selection in an aim to maximize overloaded cellular *** evaluate the performance of our algorithms by the trace data of real-word *** demonstrates the effectiveness of the strategy of taking social relationships and individual interests into account.

关键词： Mobile social network social data offloading extreme value model Gaussian graphical model

Revealing an Invasion Risk of Fish Species in Qingdao Underwater World by Environmental DNA Metabarcoding

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Journal of Ocean University of China 2021年第1期20卷 124-136页

作者： chen jianwei chen Zhi LIU Shanshan GUO Wenjie LI Di MINAMOTO Toshifumi GAO Tianxiang BGI-Qingdao BGI-ShenzhenQingdao 266555China College of Fisheries and Life Science Hainan Tropical Ocean UniversitySanya 572022China China National GeneBank BGI-ShenzhenShenzhen 518120China Qingdao Underwater World Qingdao 266003China Graduate School of Human Development and Environment Kobe UniversityKobe 657-8501Japan Fisheries College Zhejiang Ocean UniversityZhoushan 316022China

Environmental DNA(eDNA)metabarcoding has emerged as a potentially powerful tool to monitor invasive fish *** an alternative(or complementary)tool for biodiversity monitoring,e DNA metabarcoding had been used to detect species in aquariums,which represents an important transit avenue for introducing non-indigenous species with high population *** this study,eDNA metabarcoding as well as morphological characterization were used to reveal the diversity of non-indigenous species in a large aquarium at Qingdao Underwater *** DNA metabarcoding of 14 water samples at five locations from the Big Water Tank detected 24 non-indigenous species and four putative non-indigenous operational taxonomic units(OTUs).In contrast,only 20 non-indigenous species were observed by morphological *** species undetected by morphological characterization,such as Oreochromis niloticus(Linnaeus,1758),are highly adaptable to various environments and/or have invaded preferred regions where they threaten native aquatic *** metabarcoding also detected seven local fishes that were not identified by morphological ***,analysis of OTU diversity among stations and sample replications revealed that eDNA varied within and/or between *** sampling effort as well as negative controls are required to increase the detection rate of species and to eliminate false-positive OTUs.

关键词： eDNA metabarcoding fish diversity non-indigenous sampling effort aquarium

Effect of cooling rate on β→α transformation during quenching of a Zr-0.85Sn-0.4Nb-0.4Fe-0.1Cr-0.05Cu alloy

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Science China(Technological Sciences) 2012年第10期55卷 2960-2964页

作者： CHAI LinJiang LUAN BaiFeng chen jianwei ZHOU Jun LIU Qing College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Northwest Institute for Non-ferrous Metal Research Xi'an 721014China

The effect of β→α cooling rate during quenching on a new Zr-Sn-Nb-Fe-Cr-Cu alloy is *** microstructure evolution is well characterized by electron channeling contrast(ECC) imaging and transmission electron microscopy(TEM) *** results show that specimens cooled by water,liquid nitrogen,air and furnace from β-phase present martensitic,coarse basket-weave,parallel-plate and lenticular structure,*** β phase is detected by performing electron diffraction and composition analysis in the furnace cooled *** hardness values of specimens decrease while the width of α laths increase with the cooling rate *** preliminarily established quantitative relationship among the cooling rate,microstructure and mechanical properties will shed light on the microstructure control and property optimization.

关键词： zirconium alloy microstructure cooling rate phase transformation hardness

β-cyclopiazonic acid binds iron demonstrating siderophorelike activity and promotes growth in Pseudomonas aeruginosa

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Journal of Oceanology and Limnology 2023年第3期41卷 1159-1167页

作者： Yuqi GUO Youmin YING Qihao WU Bin WEI jianwei chen Hong WANG College of Pharmaceutical Science&Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals Key Laboratory of Marine Fishery Resources Exploitment&Utilization of Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310014China

This chemical study reports a novel siderophore-like compound,β-cyclopiazonic acid(1,β-CPA)extracted from marine fungus Aspergillus *** chemical structure ofβ-CPA was elucidated by a combination of extensive spectroscopic analyses and TDDFT-ECD *** iron-binding ability and CAS assays demonstrate thatβ-CPA is a novel siderophore that features a different chemical structure from those of traditional ***β-CPA has no obvious influence on the growth of bacterium Pseudomonas aeruginosa ***,its iron chelator could promote the growth of *** PAO1,suggesting that *** employed siderophores to sequester iron,which is vital for their *** study provides the physiochemical evaluation ofβ-CPA,an unusual skeletonstructure siderophore,which for the first time,was proven to have the ability to bind iron and affect *** *** new discovery of siderophore provides an opportunity for developing novel *** drugs.

关键词： marine fungi β-cyclopiazonic acid siderophore Pseudomonas aeruginosa

Chassis tra fficability simulation and experiment of a LY1352JP forest tracked vehicle

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Journal of Forestry Research 2021年第3期32卷 1315-1325页

作者： Shufa Sun Jinfeng Wu Chunlong Ren Hualin Tang jianwei chen Wenliang Ma Jiangwei Chu College of Engineering and Technology Northeast Forestry UniversityHarbin 150040People’s Republic of China Harbin Song Jiang Tractor Co. Ltd.Harbin 150010People’s Republic of China College of Transportation Northeast Forestry UniversityHarbin 150040People’s Republic of China

Based on the analysis of complex terrains and current forest transportation equipment,a forest tracked vehicle prototype LY1352 JP was *** road model and the virtual prototype of the chassis were constructed using dynamic simulation software *** optimal tension of the vehicle as well as its capabilities for crossing trenches,climbing vertical walls,uphill and downhill slopes were *** simulation results showed that the optimum tension force of the chassis of the vehicle was 63 kN(kilonewton),accounting for 45%of the total vehicle *** maximum trench crossing width and vertical obstacle climbing height were 1.35 m and 0.45 m,*** maximum uphill and downhill angles were 50°and 45°,*** on the prototype capacity for crossing trenches,and uphill and downhill driving were carried *** test results were in agreement with the simulation results.A cross-country performance of a fire truck based on the tracked vehicle chassis was conducted in an old-growth *** verified that the vehicle has a strong forest trafficability performance and can meet the needs for forest transportation.

关键词： Tracked vehicle Chassis Tra fficability RecurDyn dynamics simulation

CFD Analysis and Optimization of a Diesel Engine Cooling Water Jacket

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Fluid Dynamics & Materials Processing 2022年第3期18卷 647-659页

作者： Shunshun Qin chengfen Xie Song Li Qi Yang jianwei chen Ke Sun State Key Laboratory of Engine Reliability Weichai Power Co.Ltd.Weifang261061China School of Energy and Power Engineering Shandong UniversityJinan250061China

The STAR-CCM+software is used to investigate the flow inside a cooling water jacket of an in-line six-cylinder diesel *** results show that the average flow velocity of the cooling water inside the jacket is 1.669 m/s while the flow velocity distribution is not uniform for each ***,the fluid velocity in proximity to the cylinder head is too low,thereby affecting the cooling performances of the water *** corresponding structural optimization schemes are proposed to mitigate this issue and the post-optimization performances of the water jacket are discussed in detail.

关键词： Diesel engine cooling water jacket CFD