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区域互联网深化、信息摩擦与进口增长——基于进口二元边际视角

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山西财经大学学报 2025年第1期47卷 72-85页

作者：庄金凤马野青王冠宇南京大学商学院

信息技术发展是驱动城市数字经济发展和高水平对外开放的基础。基于此，创新性地提出考虑信息摩擦作用的垄断竞争分析框架，并从进口二元边际视角实证检验区域互联网深化对进口增长的作用。研究发现，区域互联网深化能显著促进进口规模... 详细信息

信息技术发展是驱动城市数字经济发展和高水平对外开放的基础。基于此，创新性地提出考虑信息摩擦作用的垄断竞争分析框架，并从进口二元边际视角实证检验区域互联网深化对进口增长的作用。研究发现，区域互联网深化能显著促进进口规模扩张，增长来源于进口价格、进口数量与进口种类，主要影响机制为降低信息摩擦。异质性分析表明，低对外贸易开放城市互联网深化显著降低了进口产品数量。进一步讨论发现，区域互联网深化对进口“数量”增长及“质量”增长均有促进作用。

关键词：互联网深化进口广延边际进口集约边际信息摩擦进口产品质量可变加价垄断竞争市场进口贸易

A property-based testing framework for encryption programs

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Frontiers of Computer Science 2014年第3期8卷 478-489页

作者： Chang-ai SUN Zuoyi wang guan wang School of Computer and Communication Engineering University of Science and Technology Beijing Beijing 100083 China State Key Laboratory of Computer Science Institute of Software Chinese Academy of Sciences Beijing 100190 China

In recent years, a variety of encrypfion algorithms were proposed to enhance the security of software and systems. Validating whether encryption algorithms are correctly implemented is a challenging issue. Software testing delivers an effective and practical solution, but it also faces the oracle problem （that is, under many practical situations, it is impossible or too computationally expensive to know whether the output for any given input is correct）. In this paper, we propose a property-based approach to testing encryption programs in the absence of oracles. Our approach makes use of the so-called metamorphic properties of encryption algorithms to generate test cases and verify test results. Two case studies were conducted to illustrate the proposed approach and validate its effectiveness. Experimental results show that even without oracles, the proposed approach can detect nearly 50% inserted faults with at most three metamorphic relations （MRs） and fifty test cases.

关键词： software testing encryption programs test oracles metamorphic testing (MT)

Variance Variation Criterion and Consistency in Estimating the Number of Significant Signals of High-dimensional PCA

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Acta Mathematicae Applicatae Sinica 2022年第3期38卷 513-531页

作者： guan-peng wang Heng-jian CUI School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

In this paper,we propose a criterion based on the variance variation of the sample eigenvalues to correctly estimate the number of significant components in high-dimensional principal component analysis(PCA),and it corresponds to the number of significant eigenvalues of the covariance matrix for p-dimensional *** the random matrix theory,we derive that the consistent properties of the proposed criterion for the situations that the significant eigenvalues tend to infinity,as well as that the bounded significant population *** simulation shows that the probability of estimator is correct by our variance variation criterion converges to 1 is faster than that by criterion of Passemier and Yao[Estimation of the number of spikes,possibly equal,in the high-dimensional *** Anal.,(2014)](PYC),AIC and BIC under the finite fourth moment condition as the dominant population eigenvalues tend to ***,in the case of the maximum eigenvalue bounded,once the gap condition is satisfied,the rate of convergence to 1 is faster than that of PYC and AIC,especially the effect is better than AIC when the sample size is *** is worth noting that the variance variation criterion significantly improves the accuracy of model selection compared with PYC and AIC when the random variable is a heavy-tailed distribution or finite fourth moment not exists.

关键词： consistency variance variation criterion significant eigenvalues high dimension spiked model

Efficient Distributed Estimation of High-dimensional Sparse Precision Matrix for Transelliptical Graphical Models

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Acta Mathematica Sinica,English Series 2021年第5期37卷 689-706页

作者： guan Peng wang Heng Jian CUI School of Mathematical Sciences Capital Normal UniversityBeijing 100048P.R.China

In this paper,distributed estimation of high-dimensional sparse precision matrix is proposed based on the debiased D-trace loss penalized lasso and the hard threshold method when samples are distributed into different machines for transelliptical graphical *** a certain level of sparseness,this method not only achieves the correct selection of non-zero elements of sparse precision matrix,but the error rate can be comparable to the estimator in a non-distributed *** numerical results further prove that the proposed distributed method is more effective than the usual average method.

关键词： Distributed estimator sparse precision matrix high-dimensional hard threshold efficient communication

Distributed point-to-point routing method for tasks in cloud control systems

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Journal of Systems Engineering and Electronics 2022年第4期33卷 792-804页

作者： wang guan ZHAN Yufeng XIA Yuanqing YAN Liping School of Automation Beijing Institute of TechnologyBeijing 100081China School of Information Science and Engineering Zaozhuang UniversityZaozhuang 277100China

With the rapid development of cloud computing and control theory, a new paradigm of networked control systems called cloud control systems is proposed to meet the requirements of large-scale and complex applications. Currently, cloud control systems are mainly built by using a centralized architecture. The centralized system is overly dependent on the central control plane and has huge challenges in large-scale heterogeneous node systems. In this paper, we propose a decentralized approach to establish cloud control systems by proposing a distributed point-to-point task routing method. A considerable number of tasks in the system will not rely on the central plane and will be directly routed to the target devices through the pointto-point routing method, which improves the horizontal scalability of the cloud control system. The point-to-point routing method directly gives a unique address to every task, making inter-task communication more efficient in a complex heterogeneous and busy cloud control systems. Finally, we experimentally demonstrate that the distributed point-to-point task routing approach is compatible against the state-of-the-art central systems in large-scale task situations.

关键词： cloud control system task routing cloud-edge-device cooperation

Stochastic Resonance on a Circle Without Periodic Excitation

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Chinese Physics Letters 2000年第4期17卷 249-251页

作者： QIAN Min wang guan-Xiang School of Mathematical Science Peking UniversityBeijing 100871

We analyse the appearance of coherent motion in the dynamics of the Langevin equation in the subtle case of I<1,and show that stochastic resonance does exist even in the non-critical case I<***,we show the monotonicity of the rotation number and discuss the relationship between the center frequency of the power spectrum peak and the rotation number.

关键词： number. rotation Periodic

Promising inhibitors targeting Mpro:an ideal strategy for anti-SARS-CoV-2 drug discovery

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Signal Transduction and Targeted Therapy 2020年第1期5卷 1008-1009页

作者： Yi Chen guan wang Liang Ouyang State Key Laboratory of Biotherapy and Cancer Center&Department of Gastrointestinal Surgery West China Hospitaland Collaborative Innovation Center of BiotherapySichuan University610041 ChengduChina

Recently,Dai W et *** a study on Science,1 in which the two lead compounds 11a and 11b were designed and synthesized based on the features of a key enzyme Mpro of SARSCoV-2(Fig.1).In particular,compound 11a is a potential drug candidate for coronavirus disease 2019(COVID-19)with strong anti-SARS-CoV-2 infection activity,good pharmacokinetics characteristics,and low toxicity.

关键词： al drug infection

Mechanochemical Metal-Free Synthesis of 3-Arylindenones via Unprecedented Aryl Swapping

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Chinese Journal of Chemistry 2022年第21期40卷 2539-2545页

作者： Liang Li Chuang Niu guan-Wu wang Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technologyof ChinaHefeiAnhui230026China Department of Chemistry and Chemical Engineering Hefei Normal UniversityHefeiAnhui 230601China

A triflic anhydride-induced annulation of benzoic acids bearing electron-withdrawing groups with arylalkynes leading to diverse 3-arylindenones via an unprecedented aryl swapping pathway under an air atmosphere and ball-milling conditions has been *** of the obtained 3-arylindenones are fluorine-containing *** present mechanochemical protocol employs easily available and inexpensive benzoic acids,which unexpectedly undergo aryl swapping with arylalkynes and serve as the source of the 3-aryl *** current mechanochemical methodology shows advantages including no requirement of transition-metal catalysts,ambient conditions and excellent regioselectivity for the rearrangement products,providing expedient access to 3-arylindenones containing functional groups such as F,Cl,Br,CF3,OCF3,SCF3,OAc,Ac,CO_(2)Et or NO_(2).

关键词： Mechanochemistry Rearrangement 3-Arylindenones Carboxylic acids Alkynes Green chemistry

Kinetic simulation of the transition from a pulse-modulation microwave discharge to a continuous plasma

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Plasma Science and Technology 2020年第1期22卷 45-52页

作者： guan wang Ye KUANG Yuantao ZHANG School of Electrical Engineering Shandong UniversityJinan 250061People's Republic of China

The generation of a very strong peak current in the first period(PCFP)in a pulse-modulated microwave discharge has been discussed in previous *** this paper we focus on the transition process from a pulsed discharge to a fully continuous one driven by the pulsed microwave power source by means of a kinetic *** computational results show that by increasing the duty cycle or voltage modulation rate(VMR).the discharge eventually becomes fully continuous and PCFP can no longer he *** the transition process,the distributions of the electric field,electron energy probability function(EEPF)and plasma density are discussed according to the simulation data,showing different discharge *** simulations indicate that many high-energy electrons with electron energy larger than 20eV and low-energy electrons with electron energy less than 3eV could he generated in a pulsed microwave discharge,together with a reversal electric field formed in the anode sheath when PCFP ***,only medium-energy electrons could be observed in a fully continuous ***,by investigating the transition process the pulse-modulated microwave discharges can be further optimized for plasma applications at atmospheric pressure.

关键词： atmospheric plasmas pulse modulation radio-frequency discharge.PIC-MCC model