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WFRFT modulation recognition based on HOC and optimal order searching algorithm

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Journal of Systems Engineering and Electronics 2018年第3期29卷 462-470页

作者： LIANG Yuan DA Xinyu WU Jialiang XU Ruiyang zhang zhe LIU Hujun Information and Navigation College Air Force Engineering University

A hybrid carrier（HC） scheme based on weighted-type fractional Fourier transform（WFRFT） has been proposed *** most of the works focus on HC scheme＇s inherent characteristics, little attention is paid to the WFRFT modulation *** this paper, a new theory is provided to recognize the WFRFT modulation based on higher order cumulants（HOC）. First, it is deduced that the optimal WFRFT received order can be obtained through the minimization of 4 th-order cumulants, C_（42）. Then, a combinatorial searching algorithm is designed to minimize C_（42）.Finally, simulation results show that the designed scheme has a high recognition rate and the combinatorial searching algorithm is effective and reliable.

关键词： weighted-type fractional Fourier transform(WFRFT) modulation recognition higher order cumulants(HOC) combinatorial searching algorithm

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

MMPP/M/C queue with congestion-based staffing policy and applications in operations of steel industry

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Journal of Iron and Steel Research International 2019年第7期26卷 659-668页

作者： Yan-he Jia Li-xin Tang zhe George zhang Xiao-feng Chen Liaoning Key Laboratory of Manufacturing System and Logistics Institute of Industrial and Systems Engineering Northeastern University Shenyang 110819 Liaoning China Beedie School of Business Simon Fraser University Burnaby BC V5A 1S6 Canada Department of Decision Sciences Western Washington University Bellingham WA 98225 USA

A queueing model of the Markov-modulated Poisson process (MMPP) with thresholds was investigated. The customer arrival with various arrival rates in the model was viewed as the MMPP. In contrast to the Poisson, s arrival process, the MMPP can better describe the situation that the arrival rate changes with changing conditions;therefore, the model fits better with reality. The threshold conversion was added to the model based on the general MMPP/M/C model. When the number of customers in the system exceeds a threshold, all servers work to serve;when the number of customers in the system is less than another threshold, some servers are shut down. This is the congestion-based staffing policy with two thresholds. Specifically, the problems in the slab stocking stage of slab production at the Iron and Steel Complex in China were analysed. In the slab production process, because the rate of the upstream steelmaking is not constant, the rate of slab reaching the slab yard is uncertain. The crane service is used to store slabs in a warehouse. Because the slab arrival rate varies, different numbers of cranes in service need to be optimized for cost control. Thus, MMPP was used to describe slab arrival with varied arrival rates. Therefore, an MMPP/M/C queue with thresholds was used to analyse and solve the practical problems, and the optimal number of service cranes was obtained to minimize the cost of slab stocking.

关键词： Markov-modulated Poisson process Matrix geometry Congestion-based staffing policy Threshold conversion Slab Crane

Different Turbulent Regimes and Vertical Turbulence Structures of the Urban Nocturnal Stable Boundary Layer

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Advances in Atmospheric Sciences 2023年第6期40卷 1089-1103页

作者： Yu SHI Qingcun ZENG Fei HU Weichen DING zhe zhang Kang zhang Lei LIU State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Turbulence in the nocturnal boundary layer(NBL)is still not well characterized,especially over complex underlying ***,gradient tower data and eddy covariance data collected by the Beijing 325-m tower were used to better understand the differentiating characteristics of turbulence regimes and vertical turbulence structure of urban the *** for heights above the urban canopy layer(UCL),the relationship between turbulence velocity scale(VTKE)and wind speed(V)was consistent with the“HOckey-Stick”(HOST)theory proposed for a relatively flat *** regimes have been identified according to urban nocturnal stable boundary *** 1 occurs where local shear plays a leading role for weak turbulence under the constraint that the wind speed VVT and is mainly driven by bulk *** 3 is identified by the existence of moderate turbulence when upside-down turbulence sporadic bursts occur in the presence of otherwise weak *** 4 is identified as buoyancy turbulence,when V>VT,and the turbulence regime is affected by a combination of local wind shear,bulk shear and buoyancy *** turbulence activities demonstrated a weak thermal stratification dependency in regime 1,for which within the UCL,the turbulence intensity was strongly affected by local wind shear when V<*** study further showed typical examples of different stable boundary layers and the variations between turbulence regimes by analyzing the evolution of wind *** because of the influence of large-scale motions,the power spectral density of vertical velocity for upsidedown structure showed an increase at low *** upside-down structures were also characterized by the highest frequency of the stable stratifications in the higher layer.

关键词： urban canopy layer stable boundary layer upside-down turbulence vertical structure

Effective Stacking Fault Energy in Face-Centered Cubic Metals

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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 873-877页

作者： Ke-Qiang Li zhen-Jun zhang Lin-Lin Li Peng zhang Jin-Bo Yang zhe-Feng zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

As a typical configuration in plastic deformations, dislocation arrays possess a large variation of the separation of the partial dislocation pairs in face-centered cubic（fcc） metals. This can be manifested conveniently by an effective stacking fault energy（SFE）. The effective SFE of dislocation arrays is described within the elastic theory of dislocations and verified by atomistic simulations. The atomistic modeling results reveal that the general formulae of the effective SFE can give a reasonably satisfactory prediction for all dislocation types, especially for edge dislocation arrays. Furthermore, the predicted variation of the effective SFE is consistent with several previous experiments, in which the measured SFE is not definite, changing with dislocation density. Our approach could provide better understandings of cross-slip and the competition between slip and twinning during plastic deformations in fcc metals.

关键词： Face-centered cubic Stacking fault energy - Dislocation dissociation Atomistic modeling

Microdeletions and vertical transmission of the Y-chromosome azoospermia factor region

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Asian Journal of Andrology 2023年第1期25卷 5-12页

作者： Chen-Yao Deng zhe zhang Wen-Hao Tang Hui Jiang Department of Urology Third Hospital of Peking UniversityBeijing 100089China Department of Andrology Third Hospital of Peking UniversityBeijing 100089China Department of Human Sperm Bank Third Hospital of Peking UniversityBeijing 100089China

Spermatogenesis is regulated by several Y chromosome-specific genes located in a specific region of the long arm of the Y chromosome,the azoospermia factor region(AZF).AZF microdeletions are the main structural chromosomal abnormalities that cause male *** reproductive technology(ART)has been used to overcome natural fertilization barriers,allowing infertile couples to have ***,these techniques increase the risk of vertical transmission of genetic *** widespread awareness of AZF microdeletions,the occurrence of de novo deletions and overexpression,as well as the expansion of AZF microdeletion vertical transmission,remains *** review summarizes the mechanism of AZF microdeletion and the function of the candidate genes in the AZF region and their corresponding clinical ***,vertical transmission cases of AZF microdeletions,the impact of vertical inheritance on male fertility,and the prospective direction of research in this field are also outlined.

关键词： azoospermia factor male infertility microdeletion vertical transmission

Traditional Chinese Medicine symptom pattern analysis for Parkinson's disease

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Journal of Traditional Chinese Medicine 2017年第5期37卷 688-694页

作者： Chen Hongzhi He Jiancheng Teng Long Yuan Canxing zhang zhe College of Basic Medicine Shandong University of Traditional Chinese Medicine Jinan 250355 China College of Basic Medicine Shanghai University of Traditional Chinese Medicine Shanghai 201230 China College of Foreign Language Shandong Univer-sity of Traditional Chinese Medicine Jinan 250355 China

OBJECTIVE: To use the theory of Traditional Chinese Medicine to identify the major symptom patterns of Parkinson's ***: Journal databases were searched for relevant articles in the last 30 years. Articles were reviewed for symptom patterns of Parkinson's disease and analyzed using frequency analysis, cluster analysis, and other methods of data ***: The analyses indicated that the most frequent symptom patterns of Parkinson's disease are Yin deficiency of kidney and liver, deficiency of Qi and blood, phlegm heat and wind stirring, blood stasis and wind stirring, and deficiency of Yin and ***: Taken together, the analyses identified the primary symptom patterns of Parkinson's disease as Yin deficiency of kidney and liver, deficiency of Qi and blood, phlegm heat and wind stirring, and blood stasis and wind stirring.

关键词： Parkinson disease Symptom complex Cluster analysis Data extraction

Selective synthesis of heteroleptic Pd_(2)A_(3)B-cages:modulating size-preference of supramolecular hosts via endo-functionalization

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Science China Chemistry 2024年第12期67卷 4110-4115页

作者： Wen-Tao Dai Ting-Ting Liu Qixia Bai zhe zhang Pingshan Wang Wei Lu Qi zhang Key Laboratory of Green Chemistry and Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China Institute of Environmental Research at Greater Bay Area Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006China

The size complementarity between a host and a guest is a critical prerequisite for selective molecular *** artificial host systems have been designed to achieve size-selective recognition and chemical ***,the inherent challenge lies in the fixed selectivity governed by a size-exclusion mechanism dictated by the host's *** the selectivity necessitates structural modifications of *** of host systems with modifiable sizeselectivity are *** this study,we present an approach to modulating guest-selectivity via endo-functionalization of supramolecular *** Pd_(2)A_(3)B-cages are constructed with a Pd_(2)A_(3)precursor or directly from palladium ions and relevant ***,the simultaneous and selective formation of multiple hetero-cages was achieved by simply mixing PdIIand the free ligands in a one-pot *** fidelity of the assembly process relies on cooperative steric control at the periphery and within the cavity of the hetero-cages,*** central steric group also functions as the endohedral *** of the endohedral groups facilitate facile and modular derivatization of the microenvironment within the cages,enabling the fine-tuning of guest binding affinities as evidenced by titration *** strategy offers a new solution for the development of customized host structures.

关键词： endo-functionalization heteroleptic assemblies host-guest chemistry size-selectivity metal-ligand supramolecular structures

Morphology Engineering for Covalent Organic Frameworks (COFs) by Surfactant Mediation and Acid Adjustment

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Chinese Journal of Polymer Science 2022年第4期40卷 338-344页

作者： Guang-Hui Yang zhe zhang Cong-Cong Yin Xian-Song Shi Yong Wang State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

Two-dimensional covalent organic frameworks(COFs)with specific morphologies including nanofibers and nanoplates are highly desired in both nanoscience research and practical *** far,however,morphology engineering for COFs remains challenging because the mechanism underlying the morphology formation and evolution of COFs is not well ***,we propose a strategy of surfactant mediation coupled with acid adjustment to engineer the morphology of aβ-ketoenamine-linked COF,TpPa,during solvothermal *** surfactants function as stabilizers that can encapsulate monomers and prepolymers to create micelles,enabling the formation of fiber-like and plate-like morphologies of TpPa rather than irregularly shaped *** is also found that acetic acid is important in regulating such morphologies,as the amino groups inside the prepolymers can be precisely protonated by acid adjustment,leading to an inhibited ripening process for the creation of specific *** from the synergistic enhancement of surfactant mediation and acid adjustment,TpPa nanofibers with a diameter down to~20 nm along with a length of up to a few microns and TpPa nanoplates with a thickness of~18 nm are *** work sheds light on the mechanism underlying the morphology formation and evolution of TpPa,providing some guidance for exquisite control over the growth of COFs,which is of great significance for their practical applications.

关键词： Covalent organic frameworks(COFs) Morphology engineering Surfactants Nanofibers Nanoplates