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Automated String Constraints Solving for Programs Containing String Manipulation Functions

Journal of Computer Science & Technology 2017年第6期32卷 1125-1135页

作者： Xu-Zhou zhang Yun-Zhan Gong Ya-Wen Wang Ying Xing ming-zhe zhang State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China Automation School Beijing University of Posts and Telecommunications Beijing 100876 China

The ability to solve various constraints is a principal factor of automatic constraint solvers. Most object-oriented languages treat a character string as a primitive data type which is manipulated by string library functions. Most constraint solvers have limitations on their input constraints, such as strong restrictions on the expressiveness of constraints or lack of the ability to solve hybrid constraints. These limitations hinder applying automated constraint solvers on program analysis techniques for programs containing strings and string manipulation functions. We propose an approach to automatically solve program constraints involving strings and string manipulation functions. Based on the character array model, we design a constraint language which contains primitive operations to precisely describe the constraints of commonly used string manipulation functions. The translated string constraints together with numeric constraints are then solved by a two- phase test generation procedure： firstly, a partial solution is obtained to satisfy the arithmetic constraints of the position variables, and the solution is utilized to simplify the string constraints into pure character array constraints; secondly, the pure array constraints are solved by an off-the-shelf array-specific theory based constraint solver. We integrate the approach into an automated testing tool to support the generation of string test cases, and then perform experiments. The results of the experiments prove that the integration of the proposed approach promotes the testing coverage of the existing testing tool, and the integrated tool has an advantage of handling specific string manipulation functions compared with an existing string solver.

关键词： string constraints solving satisfaction module theory program analysis software testing automated testinput generation

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Unit Test Data Generation for C Using Rule-Directed Symbolic Execution

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Journal of Computer Science & Technology 2019年第3期34卷 670-689页

作者： ming-zhe zhang Yun-Zhan Gong Ya-Wen Wang Da-Hai Jin State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876China

Unit testing is widely used in software development. One important activity in unit testing is automatic test data generation. Constraint-based test data generation is a technique for automatic generation of test data, which uses symbolic execution to generate constraints. Unit testing only tests functions instead of the whole program, where individual functions typically have preconditions imposed on their inputs. Conventional symbolic execution cannot detect these preconditions, let alone converting these preconditions into constraints. To overcome these limitations, we propose a novel unit test data generation approach using rule-directed symbolic execution for dealing with functions with missing input preconditions. Rule-directed symbolic execution uses predefined rules to detect preconditions in the individual function, and generates constraints for inputs based on preconditions. We introduce implicit constraints to represent preconditions, and unify implicit constraints and program constraints into integrated constraints. Test data generated based on integrated constraints can explore previously unreachable code and help developers find more functional faults and logical faults. We have implemented our approach in a tool called CTS-IC, and applied it to real-world projects. The experimental results show that rule-directed symbolic execution can find preconditions (implicit constraints) automatically from an individual function. Moreover, the unit test data generated by our approach achieves higher coverage than similar tools and efficiently mitigates missing input preconditions problems in unit testing for individual functions.

关键词： automated unit testing program constraint symbolic execution static analysis

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A new preparation technology of structural- gradient materials without a brittle transition zone in a Mn-Si-Cr-B bainitic cast steel

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China Foundry 2018年第4期15卷 283-290页

作者： yu-guang zhao zhe wang xiao-feng xu ming-zhe zhang wen-qiang jiang key laboratory of automobile of ministry of Education ＆school of Materials Science and Engineering Nanling Campusjilin UniversityNO.5988 Renmin streetchangchun 130025china

In the present work, a unique gradient cooling heat treatment process(GCHT) for a Mn-Si-Cr-B bainitic cast steel was developed, and microstructure and mechanical properties were examined by OM, SEM, EBSD and a uniaxial tensile test. The results showed that the structural-gradient-material(SGM) with a gradient microstructure from granular bainite to martensite was successfully produced, and it exhibited a good ductility(~13.8%) at one end and an excellent ultimate strength(~1,720 MPa) at the other end. In between the bainite and martensite, a transition region with a superior combination of tensile strength and ductility(1,700 MPa and 11.1%) was obtained, which is different from the normal knowledge of a brittle transition region. Moreover, through changing the gradient of cooling rate, the optimized SGM with a new gradient microstructure from pearlite to martensite showed a more stable structural gradient and an improved ductility(22.8%) at one end. The microstructure variation in the sample was mainly related to the carbon diffusion rate during heat treatment, and the diffusion rate could be controlled by regulating the cooling velocity. Therefore, the SGMs with different gradient microstructures could be designed to meet the needs of different properties. As a result, this work provides a new approach for preparation of the gradient structured steel, which has potential for practical application for dual-property automobile parts.

关键词： bainitic cast steel gradient cooling heat treatment structural-gradient-materials

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Protective effect of sevoflurane on lung function of elderly chronic obstructive pulmonary disease patients undergoing total hip arthroplasty

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World Journal of Clinical Cases 2023年第31期11卷 7619-7628页

作者： Yuan Yao Man-Si zhang Yue-Bing Li ming-zhe zhang Department of Anesthesiology The Second Hospital of JiaxingJiaxing 314000Zhejiang ProvinceChina Department of Pharmacy Shangrao Municipal HospitalShangrao 334000Jiangxi ProvinceChina Department of Anesthesiology The Second Affiliated Hospital of Zhejiang University of Traditional Chinese MedicineHangzhou 310005Zhejiang ProvinceChina Department of Anesthesiology Dingzhou People’s HospitalDingzhou 073000Hebei ProvinceChina

BACKGROUND Chronic obstructive pulmonary disease(COPD)is a common respiratory disorder that affects the elderly population and increases the risk of postoperative pulmonary complications(PPCs)after major *** is a volatile anesthetic that has been shown to have anti-inflammatory and antioxidant properties and attenuate lung injury in animal *** To evaluate the protective effect of sevoflurane on the lung function of elderly COPD patients undergoing total hip arthroplasty(THA).METHODS In this randomized controlled trial,we randomly assigned 120 elderly patients with COPD,who were scheduled for THA,to receive either sevoflurane(sevoflurane group)or propofol(propofol group)as the maintenance *** primary outcome was the incidence of PPCs within seven days after *** secondary outcomes were changes in the lung function parameters,inflammatory markers,oxidative stress markers,and postoperative pain *** The results showed that the incidence of PPCs was significantly lower in the sevoflurane group than in the propofol group(10%vs 25%,P=0.02).Furthermore,the decline in the forced expiratory volume in 1 s,forced vital capacity,and peak expiratory flow was significantly lesser in the sevoflurane group than in the propofol group at 24 h and 48 h after surgery(P<0.05).The interleukin-6,tumor necrosis factor-alpha,malondialdehyde,and 8-hydroxy-2α-deoxyguanosine levels were significantly lower in the sevoflurane group than in the propofol group at 24 h after surgery(P<0.05).The sevoflurane group showed significantly lower postoperative pain scores than the propofol group at 6 h,12 h,and 24 h after surgery(P<0.05).CONCLUSION Sevoflurane protects the lung function of elderly COPD patients undergoing THA under general anesthesia by reducing the incidence of PPCs,attenuating inflammatory and oxidative stress responses,and alleviating postoperative pain.

关键词： Sevoflurane Propofol Lung function Chronic obstructive pulmonary disease Total hip arthroplasty Elderly patients Inflammatory markers

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Colonic tubular duplication combined with congenital megacolon:A case report

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World Journal of Clinical Cases 2022年第34期10卷 12768-12774页

作者： zhe-ming zhang Shuai Kong Xin-Xin Gao Xiang-Hao Jia Chun-Ning zheng School of Clinical Medicine Weifang Medical UniversityWeifang 261053Shandong ProvinceChina Department of Gastrointestinal Surgery Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250000Shandong ProvinceChina

BACKGROUND Colonic duplication refers to a spherical or tubular cavity which shows similar properties with the native colon and is attached to the mesenteric side of the alimentary *** is the rarest in alimentary tract *** upon anatomic feature,colonic duplications can be classified as spherical(cystic)or tubular,with the latter being less common(approximately 20%).Symptoms of colonic duplication are dependent on the duplication site and extent,and patient age,***,patients with colonic duplication manifest typical intestinal obstruction,potentially accompanied by recurrent dark or bright red bloody stool,varying degrees of anemia-related symptoms,and body *** SUMMARY A young male patient was admitted to our hospital due to recurrent abdominal *** definite diagnosis was achieved by computed tomography(CT)or electronic colonoscopy,and the bowel preparation efficacy was *** disease was suspected,and thus laparoscopic exploration was *** approximately 60-cm-long inverted duplicated colon with severe edema and dilation was *** originated from the mesenteric side of the transverse colon and ended in the terminal part of the descending colon with a blind *** parallel native colon had a thickened colonic wall,became stiff,and was poor in *** patient then underwent subtotal colectomy and was discharged 7 d after the *** 3 mo post-surgery to date,the patient had regular bowel movement once daily and a steady increase in body *** Tubular colonic duplication is a rare type of alimentary tract duplication that can be detected by ultrasonography,CT,or magnetic resonance imaging based on the actual clinical *** resection of aberrant colon(including the duplicated colonic segment and other potentially involved colonic segments)is the only approach to cure this medical condition.

关键词： Colonic duplication Chronic constipation Subtotal colectomy Congenital megacolon Case report

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O-METHYLLAUREOLOL FROM SKIMMIA LAUREOLA

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Chinese Chemical Letters 1995年第10期6卷 873-874页

作者： Hong Jie zhang Xin Feng GAO ming zhe zhang(Department of Chemistry, Peking University, Beijing 100871) (Bruker Instruments Ltd.,Beijing) Beijing Univ Dept Chem Beijing 100871 Peoples R China

A new triterpene alcohol was isolated and identified by spectral analyses from Skimmia laureola ssp. multinervia which was collected from Yunnan province of China and named O-methyllaureolol.

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An integrated supramolecular fungicide nanoplatform based on pH-sensitive metal–organic frameworks

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Chinese Chemical Letters 2023年第10期34卷 153-158页

作者： Chao-Yi Wang Yu-Qing Liu Chengguo Jia ming-zhe zhang Chun-Li Song Changling Xu Ran Hao Jian-Chun Qin Ying-Wei Yang College of Chemistry Jilin UniversityChangchun 130012China College of Plant Science Jilin UniversityChangchun 130062China

The construction of an integrated nanoplatform with controlled fungicide delivery features in the specific microenvironment produced by fungal pathogens is a highly desirable strategy to improve the utilization of fungicides. Herein, we report a supramolecular fungicide delivery system based on benzimidazolemodified NH_(2)-MIL-101(Fe) metal–organic frameworks(B-MIL-101(Fe) MOFs) as carriers loaded with osthole(OS), and β-cyclodextrin(β-CD) as nanovalves to form β-CD@B-MIL-101(Fe)-OS. The nanoplatform can release the loaded OS for fungus control through self-degradation of the MOFs skeleton in an oxalic acid microenvironment produced by Botrytis cinerea. The experimental results exhibit that the constructed supramolecular fungicide delivery system could effectively inhibit mycelial growth and protect the tomatoes from infection by B. cinerea during the ripening stage. This strategy constructs a facile and integrated supramolecular drug delivery system for B. cinerea control and opens up a new avenue for the sustainable development of modern agriculture.

关键词： Controlled release Fungicidenanoplatform Host-guest chemistry Microenvironment-responsive Supramolecularchemistry

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Skyway:Accelerate Graph Applications with a Dual-Path Architecture and Fine-Grained Data Management

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Journal of Computer Science & Technology 2024年第4期39卷 871-894页

作者： Mo Zou ming-zhe zhang Ru-Jia Wang Xian-He Sun Xiao-Chun Ye Dong-Rui Fan Zhi-Min Tang Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Institute of Information Engineering Chinese Academy of SciencesBeijing 100045China Department of Computer Science Illinois Institute of TechnologyChicagoIL 60616U.S.A.

Graph processing is a vital component of many AI and big data ***,due to its poor locality and complex data access patterns,graph processing is also a known performance killer of AI and big data *** this work,we propose to enhance graph processing applications by leveraging fine-grained memory access patterns with a dual-path architecture on top of existing software-based graph *** first identify that memory accesses to the offset,edge,and state array have distinct locality and impact on *** then introduce the Skyway architecture,which consists of two primary components:1)a dedicated direct data path between the core and memory to transfer state array elements efficiently,and 2)a data-type aware fine-grained memory-side row buffer hardware for both the newly designed direct data path and the regular memory hierarchy data *** proposed Skyway architecture is able to improve the overall performance by reducing the memory access interference and improving data access efficiency with a minimal *** evaluate Skyway on a set of diverse algorithms using large real-world *** a simulated fourcore system,Skyway improves the performance by 23%on average over the best-performing graph-specialized hardware optimizations.

关键词： graph application computer architecture memory hierarchy

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Decision making module based on stochastic magnetic tunnel junctions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 202-209页

作者： Yifan Miao Li Zhao Yajun zhang zhe Yuan Center for Advanced Quantum Studies and Department of Physics Beijing Normal University Institute for Nanoelectric Devices and Quantum Computing Fudan University Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan University

In biological neural systems, noise is ubiquitous but does not affect the correct decisions made in the complex cognitive ***-making in biological neural system is typically achieved by accumulating input information over a period of *** by recent developments in neurosciences, we design a decision-making module based on spintronic devices, utilizing superparamagnetic tunnel junctions as artificial neurons. The feasibility of this decision-making module is verified through circuit simulations. Taking a multi-layer perceptron as an example, the module significantly improves the accuracy of the perceptron in the handwritten digit recognition task. Furthermore, the spintronic decision-making module offers advantages over the conventional pooling methods, such as adaptive decision time, high performance and the absence of analog-to-digital conversion. The decision-making module is flexible to be integrated into artificial neural networks and provides a general yet effective solution to enhance performance against device noise.

关键词： neuromorphic computing spintronics magnetic tunnel junction neural networks

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Fluorinated poly(p-triphenylene isatin) anion exchange membranes based on hydrophilic hydroxyl side chain modulation for fuel cells

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Journal of Energy Chemistry 2025年第1期100卷 702-709页

作者： Yiman Gu Yanchao zhang Zhanyu Li Yijia Lei Baozeng Sun Xiaoyu Yu zhe Wang College of Chemistry and Life Science Changchun University of Technology College of Chemical Engineering Changchun University of Technology School of Materials Science and Engineering Changchun University of Technology Key Laboratory of Advanced Functional Polymer Membrane Materials of Jilin Province

The development of alkaline fuel cells is moving forward at an accelerated pace,and the application of ether-free bonded polymers to anion exchange membranes （AEMs） has been widely ***,the question of the“trade-off”between AEM ionic conductivity and dimensional stability remains *** strategy of inducing microphase separation to improve the performance of AEM has attracted much attention recently,but the design of optimal molecular structures is still being ***,this work introduced different ratios of 3-bromo-1,1,1-trifluoroacetone （x=40,50,and 60） into the main chain of poly（p-terphenylene isatin）.Because fluorinated groups have excellent hydrophobicity,hydrophilic hydroxyl-containing side chains are introduced to jointly adjust the formation of phase separation *** results show that PTI-PTF50-NOH AEM with the appropriate fluorinated group ratio has the best ionic conductivity and alkali stability under the combined effect of *** has an ionic conductivity of 133.83 mS cm-1at 80°*** addition,the OH-conductivity remains at 89%of the initial value at 80°C and 3 M KOH for 1056 h of *** cell polarization curve based on PTI-PTF50-NOH shows a power density of 734.76 mW cm-2at a current density of 1807.7 mA cm-2.

关键词： Potassium hydroxide

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