检索结果-南通市图书馆

The Reciprocal and Symbiotic Effects of Industrial Relocation between China and BRI Countries

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Economist 2023年第5期18卷 54-75页

作者： liu Youjin zhou Jian Zeng xiaoming Business School Hunan University of Science and TechnologyXiangtanChina

Reciprocity and symbiosis are essential to the creation of“a community with a shared future for mankind”,and industrial relocation is a key strategy for implementing the Belt and Road Initiative(BRI).This paper investigates the reciprocal and symbiotic effects of industrial relocation between China and BRI countries,and performs an empirical test using the Eora global supply chain database of *** findings suggest that there has been an increasing level of industrial reciprocity and symbiosis between China and BRI countries,but great differences exist across sectors and regions;industrial relocation between China and BRI countries is conducive to two-way industrial reciprocity and symbiosis primarily through regional value chain cooperation and an increasing level of industrial *** most substantial effects have been observed in industrial relocation involving developed BRI countries,in medium-and high-tech sectors,and following the announcement of the BRI.

关键词： Belt and Road Initiative(BRI) reciprocity and symbiosis global value chains(GVCs) industrial relocation

A Study of Using Synthetic Data for Effective Association Knowledge Learning

在线全文

学校读者我要写书评

暂无评论

Machine Intelligence Research 2023年第2期20卷 194-206页

作者： Yuchi liu Zhongdao Wang Xiangxin zhou Liang zheng College of Engineering&Computer Science Australian National UniversityCanberra 2601Australia Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

Association,aiming to link bounding boxes of the same identity in a video sequence,is a central component in multi-object tracking(MOT).To train association modules,e.g.,parametric networks,real video data are usually ***,annotating person tracks in consecutive video frames is expensive,and such real data,due to its inflexibility,offer us limited opportunities to evaluate the system performance *** tracking *** this paper,we study whether 3D synthetic data can replace real-world videos for association ***,we introduce a large-scale synthetic data engine named MOTX,where the motion characteristics of cameras and objects are manually configured to be similar to those of real-world *** show that,compared with real data,association knowledge obtained from synthetic data can achieve very similar performance on real-world test sets without domain adaption *** intriguing observation is credited to two *** and foremost,3D engines can well simulate motion factors such as camera movement,camera view,and object movement so that the simulated videos can provide association modules with effective motion ***,the experimental results show that the appearance domain gap hardly harms the learning of association *** addition,the strong customization ability of MOTX allows us to quantitatively assess the impact of motion factors on MOT,which brings new insights to the community.

关键词： Multi-object tracking(MOT) data association synthetic data motion simulation association knowledge learning

Study on the epoxidation of olefins with H_(2)O_(2)catalyzed by biquaternary ammonium phosphotungstic acid

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2023年第6期58卷 146-154页

作者： Zijie Zhang Qianyu Zha Ying liu Zhibing Zhang Jia liu zheng zhou School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210093China

Selective epoxidation of olefins is an important field in chemical *** this work,we developed a new phosphotungstic acid catalyst{[(C_8H_(17))(CH_(3))_(2)N]_(2)(CH_(2))_(3)}_(1.5){PO_(4)[WO(O_(2))_(2)]_(4)}with long carbon chain and biquaternary ammonium *** could be epoxidized to cyclohexene oxide in 96.3%conversion and 98.2%*** catalyst type,solvent type,catalyst loading,initial molar ratio,temperature,cycle performance and substrate extensibility were studied and optimized,the kinetic parameters about overall reaction and unit reaction were also *** light scattering analysis was carried out to explain the different catalytic performance between catalysts with different carbon chain *** novel catalyst and the corresponding dynamics and mechanism study could probably help the industrial application on the epoxidation of cyclohexene with H_(2)O_(2).

关键词： Epoxidation of olefins Phosphotungstic acid Cyclohexene Kinetic study

Effect of Ti-V-Nb-Mo addition on microstructure of high chromium cast iron

在线全文

学校读者我要写书评

暂无评论

China Foundry 2012年第2期9卷 148-153页

作者： Ma Youping Li Xiulan liu Yugao zhou Shuyi Dang xiaoming School of Metallurgic Engineering Xi'an University of Architecture&TechnologyXi'an 710055China School of Mechanical and Electrical Engineering Qingdao Agricultural UniversityQingdao 266109China

The effects of trace additions of multi-alloying elements （Ti, Nb, V, Mo） on carbides precipitation and ascast microstructure of eutectic high chromium cast iron containing 2.85wt.%C and 31.0wt.%Cr were investigated from thermodynamic and kinetic considerations. The thermodynamic calculations show that Ti and Nb exist in the multi-alloying system in the forms of TiC and NbC. The formation of VC during the solidification is not feasible from the thermodynamic consideration. XRD analysis shows that the V exists in alloy compounds （VCr2C2, VCrFes）. The first precipitated high melting point particles （TIC, NbC） can act as the heterogeneous substrate of M7C3 carbides, which results in significant refinement of the M7C3 carbides. After the addition of alloying elements, C atom diffusion is hindered due to the strong affinities of the strong carbide forming elements for carbon, which decreases the growth rate of carbides. The combined roles of the increase of nucleation rate and the decrease of carbides growth rate lead to the finer microstructure.

关键词： high chromium cast iron microstructure alloying thermodynamics kinetics

Optimized Relinearization Algorithm of the Multikey Homomorphic Encryption Scheme

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2022年第3期27卷 642-652页

作者： Xiaoyuan Yang Shangwen zheng Tanping zhou Yao liu Xiaoliang Che College of Cryptographic Engineering Engineering University of PAPXi’an 710086China

Multikey homomorphic encryption(MKHE) supports arbitrary homomorphic evaluation on the ciphertext of different users and thus can be applied to scenarios involving multiusers(e.g., cloud computing and artificial intelligence) to protect user privacy. CDKS19 is the current most efficient MKHE scheme, and its relinearization process consumes most of the time of homomorphic evaluation. In this study, an optimized relinearization algorithm of CDKS19 is proposed. This algorithm reorganizes the evaluation key during the key generation process, decreases the complexity of relinearization, and reduces the error growth rate during homomorphic evaluation. First, we reduce the scale of the evaluation key by increasing its modulus instead of using a gadget vector to decompose the user’s public key and extend the ciphertext of homomorphic multiplication. Second, we use rescaling technology to optimize the relinearization algorithm;thus, the error bound of the ciphertext is reduced, and the homomorphic operation efficiency is improved. Lastly, the average-case error estimation on the variances of polynomial coefficients and the upper bound of the canonical embedding map are provided. Results show that our scheme reduces the scale of the evaluation key, the error variance, and the computational cost of the relinearization process. Our scheme can effectively perform the homomorphic multiplication of ciphertexts.

关键词： multikey homomorphic encryption relinearization evaluation key rescaling

Multi-functional single-source acoustic tweezer

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2023年第12期66卷 129-135页

作者： Xuemei Ren Qinxin zhou Jie Huang zheng Xu Xiaojun liu Institute of Acoustics Tongji UniversityShanghai 200092China MOE Key Laboratory of Modern Acoustics Department of PhysicsNanjing UniversityNanjing 210093China

Acoustic tweezers have gained considerable attention due to their potential and important role in various applications.A costeffective and precise method for manipulating particles is using 3D-printed acoustic holographic ***,this technique is limited in its determined function for particle manipulation with a single holographic *** propose a method to overcome this limitation by constructing a multi-functional acoustic tweezer,which is capable of achieving diverse functions of particle *** demonstrate the ability to achieve fixed-angle rotation of a rectangular particle,multi-pattern particles arrangement,selectable left-right movement of a particle on a line,and completing two distinct trajectories with a single *** proposed method offers a flexible and real-time controlling approach for acoustic tweezers,which can partially substitute the phased arrays with high circuit complexity.

关键词： acoustic hologram acoustic tweezer particle transport

Experimental,Numerical,and Analytical Studies on the Bending of Mechanically Lined Pipe

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第2期38卷 221-232页

作者： WEI Wen-bin YUAN Lin zhou Jia-sheng liu zheng State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China School of Mechanical Engineering Tianjin UniversityTianjin 300072China

Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion *** installation and operation,the pipe may undergo severe bending deformation,which causes the liner to separate from the outer pipe and buckles,affecting the stability of the whole *** this paper,the buckling response of MLP subjected to bending is investigated to clarify its bending characteristics by employing both experiments,numerical simulation,as theoretical *** types of MLPs were manufactured with GB 45 carbon steel(SLP)and Al 6061(ALP)used as the outer pipe material,*** hydraulic expansion and bending experiments of small-scale MLPs are *** addition to the ovalized shape of the cross-section for the SLP specimens,the copper liner was found to wrinkle on the compressive *** contrast,the liner of ALP remains intact without developing any wrinkling and collapse *** addition,a dedicated numerical framework and theoretical models were also *** was found both the manufacturing and bending responses of the MLP can be well reproduced,and the predicted maximum moment and critical curvatures are in good agreement with the experimental results.

关键词： lined pipe bending nonlinear ring theory buckling plasticity

Modeling and Simulation of a Hybrid Jet-Impingement/Micro-Channel Heat Sink

在线全文

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2021年第1期17卷 109-121页

作者： Taidong Xu Hao liu Dejun Zhang Yadong Li xiaoming zhou Research Institute of CSIC Nanjing211153China University of Electronic Science and Technology of China Chengdu611731China

With the progressive increase in the number of transistors that can be accommodated on a single integrated circuit,new strategies are needed to extract heat from these devices in an efficient *** this regard methods based on the combination of the so-called“jet impingement”and“micro-channel”approaches seem extremely promising for possible improvement and future applications in electronics as well as the aerospace and biomedical *** this paper,a hybrid heat sink based on these two technologies is analysed in the frame of an integrated *** CFD simulation of the coupled flow/temperature fields and orthogonal tests are performed in order to optimize the overall *** influence of different sets of structural parameters on the cooling performance is *** is shown that an optimal scheme exists for which favourable performance can be obtained in terms of hot spot temperature decrease and thermal uniformity improvement.

关键词： Jet impingement micro-channel heat sink numerical simulation orthogonal test

GIS-based Analysis for Hotspot Identification of Tradeoff Between Ecosystem Services： A Case Study in Yanhe Basin, China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Geographical Science 2016年第4期26卷 466-477页

作者： zheng Zhenmin FU Bojie FENG xiaoming State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Joint Center for Global Change Studies Beiiing 100875 China

Although the quantification and valuation of ecosystem services have been studied for a long time, few studies have specifi- cally focused on the quantification of tradeoffs between ecosystem services and tradeoff hotspots, Based on previous studies of ecosys- tem service assessment, we proposed a feasible method to analyze the tradeoffs between ecosystem services, including determination of their relationship, quantification of tradeoffs, and identification of tradeoff hotspots. Potential influencing factors were then further ana- lyzed. The Yanhe Basin in the Loess Plateau was selected as an example to demonstrate the application process. Firstly, the amounts of net primary production （NPP） and water yield （WY） in 2000 and 2008 were estimated by using biophysical models, Secondly, correla- tion analysis was used to indicate the tradeoffs between NPP and WY. Thirdly, tradeoff index （TINpp/wy） was established to quantify the extent of tradeoffs between NPP and WY, and the average value of TINpp/wy is 24.4 g/（mm·m2） for the Yanhe Basin between 2000 and 2008. Finally, the tradeoff hotspots were identified. The results indicated that the area of lowest tradeoff index concentrated in the mid- dle part of the Yanhe Basin and marginal areas of the southern basin. Map overlapping was used for preliminary analysis to seek poten- tial influencing factors, and the results showed that shrub was the best suited for growing in the Yanhe Basin, but also was a potential irtfluencing factor for formulatiort of the tradeoff hotspots. The concept of tradeoff index could also be used to quantify the degree of synergy between different ecosystem services. The method to identify the tradeoff hotspots could help us to narrow the scope of study area for further research on the relationship among ecosystem services and concentrate on the potential factors for formation of tradeoff between ecosystem services, enhance the capacity to maintain the sustainability of ecosystem.

关键词： correlation analysis net primary productivity water yield tradeoff index inlluencing tactor