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Zr-in-rutile thermometry in eclogite at Jinheqiao in the Dabie orogen and its geochemical implications

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Chinese Science Bulletin 2008年第5期53卷 768-776页

作者： chen zhenyu LI QiuLi Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Trace element analysis was made by an electron microprobe on rutiles from ultrahigh-pressure ec-logite at Jinheqiao in the Dabie orogen. The results show Zr contents of 37 to 118 μg·g?1, with signifi-cant variations between grains within the same thin section. Zr-in-rutile temperatures were calculated by the pressure-dependent thermometer, yielding 595 to 678℃ at 4.1 GPa for the upper limit of meta-morphic pressures. The temperatures are about 200 to 250℃ lower than temperatures of 846±70℃ calculated from garnet-omphacite Fe-Mg partition geothermometry, but 150 to 200℃ higher than ~460℃ from quartz-rutile O isotope temperatures and rutile Pb diffusion closure temperature for the same specimen. This indicates that the diffusion rate of Zr in rutile is remarkably slower than that of Pb and O in rutile, and that the temperature of Zr-in-rutile is higher than the closure temperature corre-sponding to cooling age as dated by rutile U-Pb radiometric system. The latter is consistent with ex-perimental result of Zr diffusion in rutile. Diffusion and re-crystallization with intensive retrograde fluid during exhumation of UHP metamorphic rocks may be the major reason why the Zr contents in rutile decreased and thus did not provide the record of the peak metamorphic temperatures. The remarkable difference in Zr content between rutile grains suggests that the distribution of Zr in rutile was in the state of disequilibrium due to differential diffusion and retrograde resetting.

关键词：地球化学大白造山带金红石温度测定榴辉岩地质年代测定

Automatic test report augmentation to assist crowdsourced testing

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Frontiers of Computer Science 2019年第5期13卷 943-959页

作者： Xin chen He JIANG zhenyu chen Tieke HE Liming NIE School of Computer Science and Technology Hangzhou Dianzi University Hangzhou 310018 China School of Software Dalian University of Technology Dalian 116621 China Key Laboratory for Ubiquitous Network and Service Software of Liaoning Province Dalian 116621 China School of Software Nanjing University Nanjing 210093 China School of Information Science and Technology Zhejiang Sci-Tech University Hangzhou 310018 China

In crowdsourced mobile application testing, workers are often inexperienced in and unfamiliar with software testing. Meanwhile, workers edit test reports in descriptive natural language on mobile devices. Thus, these test reports generally lack important details and challenge developers in understanding the bugs. To improve the quality of inspected test reports, we issue a new problem of test report augmentation by leveraging the additional useful information contained in duplicate test reports. In this paper, we propose a new framework named test report augmentation framework (TRAF) towards resolving the problem. First, natural language processing (NLP) techniques are adopted to preprocess the crowdsourced test reports. Then, three strategies are proposed to augment the environments, inputs, and descriptions of the inspected test reports, respectively. Finally, we visualize the augmented test reports to help developers distinguish the added information. To evaluate TRAF, we conduct experiments over five industrial datasets with 757 crowdsourced test reports. Experimental results show that TRAF can recommend relevant inputs to augment the inspected test reports with 98.49% in terms of NDCG and 88.65% in terms of precision on average, and identify valuable sentences from the descriptions of duplicates to augment the inspected test reports with 83.58% in terms of precision, 77.76% in terms of recall, and 78.72% in terms of F-measure on average. Meanwhile, empirical evaluation also demonstrates that augmented test reports can help developers understand and fix bugs better.

关键词： crowdsourced testing test report TF-IDF natural language processing test report augmentation

Calibration of microwave network analyzer

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Science China(Technological Sciences) 2004年第2期47卷 141-149页

作者： ZHU Ninghua WANG Youlin chen zhenyu The State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China The State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China The State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

This paper presents a systematic description of the methods for calibrating microwave network analyzer and test fixtures, and discusses the problems arising in the calibration. The general criteria for choosing calibration standards and corresponding algorithms are discussed and suggestions to overcome these problems and improve the calibration accuracy are also given. It has been found that for reciprocal test fixtures, the four equations obtained with the thru standard can be used at the same time. Meanwhile,the calibration accuracy can be improved. It has been shown that using the same calibration procedures but different algorithms may lead to the occurrence of frequency limitation.

关键词： calibration, microwave network analyzer, scattering parameter measurement, test fixture.

Molecular packing tuning via chlorinated end group enables efficient binary organic solar cells over 18.5%

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Carbon Energy 2024年第3期6卷 196-203页

作者： Yafeng Li zhenyu chen Xingzheng Yan Ziyi Ge Zhejiang Business Technology Institute NingboZhejiangChina Zhejiang Engineering Research Center for Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingboZhejiangChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina

Designing novel nonfullerene acceptors(NFAs)is of vital importance for the development of organic solar cells(OSC).Modification on the side chain and end group are two powerful tools to construct efficient ***,based on the high-performance L8BO,we selected 3-ethylheptyl to substitute the inner chain of 2-ethylhexyl,obtaining the backbone of *** we introduced different halogen atoms of fluorine and chlorine on 2-(3-oxo-2,3-dihydro-1Hinden-1-ylidene)malononitrile end group(EG)to construct efficient NFAs named BON3-F and BON3-Cl,*** donor D18 was chosen to combine with two novel NFAs to construct OSC ***,D18:BON3-Cl-based device shows a remarkable power conversion efficiency(PCE)of 18.57%,with a high open-circuit voltage(V_(OC))of 0.907 V and an excellent fill factor(FF)of 80.44%,which is one of the highest binary PCE of devices based on D18 as the ***,BON3-F-based device shows a relatively lower PCE of 17.79%with a decreased FF of 79.05%.The better photovoltaic performance is mainly attributed to the red-shifted absorption,higher electron and hole mobilities,reduced charge recombination,and enhanced molecular packing in the D18:BON3-Cl ***,we performed stability tests on two binary systems;the D18:BON3-Cl and D18:BON3-F devices maintain 88.1%and 85.5%of their initial efficiencies after 169 h of storage at 85°C in an N2-filled glove box,*** work demonstrates the importance of selecting halogen atoms on EG and provides an efficient binary system of D18:BON3-Cl for further improvement of PCE.

关键词： binary organic solar cell chlorinated end group molecular packing

Iterative Android automated testing

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Frontiers of Computer Science 2023年第5期17卷 15-26页

作者： Yi ZHONG Mengyu SHI Youran XU Chunrong FANG zhenyu chen State Key Laboratory for Novel Software Technology Nanjing UniversityNanjing 210093China School of Big Data and Computer Science Chongqing College of Mobile CommunicationChongqing 400065China

With the benefits of reducing time and workforce,automated testing has been widely used for the quality assurance of mobile applications(APPs).Compared with automated testing,manual testing can achieve higher coverage in complex interactive *** the effectiveness of manual testing is highly dependent on the user operation process(UOP)of experienced *** on the UOP,we propose an iterative Android automated testing(IAAT)method that automatically records,extracts,and integrates UOPs to guide the test logic of the tool across the complex Activity *** feedback test results can train the UOPs to achieve higher coverage in each *** extracted 50 UOPs and conducted experiments on 10 popular mobile APPs to demonstrate IAAT’s effectiveness compared with Monkey and the initial automated *** experimental results show a noticeable improvement in the IAAT compared with the test logic without human *** the 60 minutes test time,the average code coverage is improved by 13.98%to 37.83%,higher than the 27.48%of Monkey under the same conditions.

关键词： quality assurance automated testing UOP test coverage

An empirical study on constraint optimization techniques for test generation

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Science China(Information Sciences) 2017年第1期60卷 69-83页

作者： Zhiyi ZHANG zhenyu chen Ruizhi GAO Eric WONG Baowen XU State Key Laboratory for Novel Software Technology Nanjing University Department of Computer Science University of Texas at Dallas

Constraint solving is a frequent, but expensive operation with symbolic execution to generate tests for a program. To improve the efficiency of test generation using constraint solving, four optimization techniques are usually applied to existing constraint solvers, which are constraint independence, constraint set simplification, constraint caching, and expression rewriting. In this paper, we conducted an empirical study, using these four constraint optimization techniques in a well known test generation tool KLEE with 77 GNU Coreutils applications, to systematically investigate how these optimization techniques affect the efficiency of test generation. The experimental results show that these constraint optimization techniques as well as their combinations cannot improve the efficiency of test generation significantly for ALL-SIZED programs. Moreover, we studied the constraint optimization techniques with respect to two static metrics, lines of code(LOC) and cyclomatic complexity(CC), of programs. The experimental results show that the "constraint set simplification" technique can improve the efficiency of test generation significantly for the programs with high LOC and CC values. The"constraint caching" optimization technique can improve the efficiency of test generation significantly for the programs with low LOC and CC values. Finally, we propose four hybrid optimization strategies and practical guidelines based on different static metrics.

关键词： test generation symbolic execution constraint solving constraint optimization static metric

The complexity of variable minimal formulas

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Chinese Science Bulletin 2010年第18期55卷 1957-1960页

作者： chen zhenyu XU BaoWen DING Decheng National Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China Software Institute Nanjing University Nanjing 210093 China Department of Mathematics Nanjing University Nanjing 210093 China

Based on the common properties of logic formulas:equivalence and satisfiability,the concept of variable minimal formulas with property preservation is introduced.A formula is variable minimal if the resulting sub-formulas with any variable omission will change the given *** theoretical results of two classes:variable minimal equivalence(VME) and variable minimal satisfiability(VMS) are *** prove that VME is NP-complete,and VMS is in DP and coNP-hard.

关键词：逻辑公式复杂性 VME总线 NP完全问题可满足性财产保全 VMS 等价

The study of protection coordination technology in power system based on Multi-Agent

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微计算机信息 2007年第36期23卷 21-23页

作者： chen zhenyu South china unlversity of technology Guangdong business college

This paper studies mainly how to make use of Multi- Agent technology to solve the complex problems which are caused by unsuitable coordination between protection and untimely action and protection fault activity in large power system, and realizes timely the coordination among protections effectively in when losing some or all information. Thus it overcomes the difficult of solving single or shore range information, enhances correspond and coordination among the intelligent protect Agent, raises the stable and reliable property, and promotes the process of power network for large area.

关键词：动力系统多代理技术保护调和功能人工智能

Predicting the utilization factor of blasthole in rock roadways by random forest

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Underground Space 2023年第4期11卷 232-245页

作者： Xinmin Ma zhenyu chen Pan chen Haozhang Zheng Xingyu Gao Junjie Xiang Liying chen Yipei Huang School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China Big Data Center State Grid Corporation of ChinaBeijing 100052China China Electric Power Research Institute Beijing 100192China China University of Mining and Technology Jiangsu 221008China Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China Griffith University Queensland 4702Australia

The utilization factor of blasthole is a crucial indicator of the effectiveness of blasting in rock roadways.A significant value means that the explosive energy is fully utilized,the single-cycle advance is high,and the excavation rate is fast.A good blasting programme is a prerequisite for improving the utilization rate and predicting the utilization rate before blasting operations can verify the feasibility of the blasting ***,a database of rock roadway blasting covering different geological and production conditions is ***,error analysis and the Gini coefficient method are used to weight the characteristic variables,quantify the importance of the variables and identify eight key indicators affecting the blasting hole utilization ***,a random forest algorithm-based model for predicting utilization factor of blasthole is proposed,and the results of the model on the test set are:root mean square error(RMSE)is 0.0137,mean absolute error(MAE)is 0.0087,and coefficient of determination(R^(2))is *** performance of this method is com-pared with that of the neural network and support vector machine models on the test sets to verify the superiority of the random forest ***,to verify the generalization ability and practicality of the random forest prediction model,the model is applied to the rock roadway blasting construction of Gu Bei coal mine in Anhui *** results show that R2 is 0.913,so the model is reliable and accurate,which can meet the actual engineering requirements and lay the foundation for the promotion and application of this technology.

关键词： Rocky roadways Utilization factor of blasthole Random forest Prediction