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The Influence of Aerodynamic Unsteady Effect on Maneuver Load of Aircraft Horizontal Tail

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International Journal of Plant Engineering and Management 2019年第4期24卷 193-205页

作者： zhang jian′gang The First Aircraft Institute of Aviation Industry Corporation of China

In this paper, the unsteady effect of airflow is introduced into the calculation of aircraft maneuver load, and the results are compared with those obtained by quasi-steady method. Taking the steep pitch maneuver of an aircraft as an example, two methods are used to calculate the aircraft response after the rudder input is given according to the specifications. The calculation results show that if the peak overload of the aircraft is the same, the horizontal tail load increases by about 1% when the unsteady effect of the airflow is taken into account. If the rudder input of the two methods is the same, the unsteady calculation method will increase more. At the same time, the calculation shows that the bigger the deflection speed of rudder surface is, the bigger the difference between them is. Therefore, in order to improve the design quality of aircraft, it is necessary to introduce the unsteady effect into the calculation of loads in the detailed design stage of aircraft.

关键词： unsteady effect maneuver load rapid pitch linear systems load of horizontal tail

Establishment of cervical lymph node metastasis model of squamous cell carcinoma in the oral cavity in mice

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Chinese Medical Journal 2008年第19期121卷 1891-1895页

作者： SUN Rui zhang jian-gang GUO Chuan-bin Department of Oral and Maxillofacial Surgery School and Hospital of Stomatology Peking University Beijing 100081 China Department of Pathology School of Basic Medical Sciences Lanzhou University Lanzhou Gansu 730000 China

Background Oral squamous cell carcinoma （OSCC） is the most prevalent malignant tumor in the head and neck region, comprising more than 90% of all oral malignancies. A feasible approach for an animal model to study OSCC lymph node metastasis was established and biological behaviors of three oral squamous cell carcinoma cell lines were compared. Methods After implanting three kinds of cell lines （GDC185, Tca8113, Tca83） into three different anatomical sites in nude mice, namely the tongue, floor of the mouth, and axillary fossa, we observed the tumorigenicity and the metastatic capacity, which was confirmed by histopathology under a surgical microscope. Results The animal model injected with GDC185 cells into the floor of the mouth had the highest rate of neck lymph node metastasis （55.6%） and the cell lines had significantly different biological behaviors. Conclusions Nude mice injected with GDC185 cells into the floor of the mouth could be used as a feasible animal model to study neck metastasis of oral squamous cell carcinoma.

关键词： animal model, lymphatic metastasis squamous cell carcinoma mouth neoplasm

Some Characterizations of GV-semigroups

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Chinese Quarterly Journal of Mathematics 2007年第1期22卷 104-108页

作者： zhang jian-gang SHEN Ran Department of Mathematics Shanghai Normal University Shanghai 200234 Ghina Gollege of Science Donghua University Shanghai 201600 China

GV-semigroups are the generalizations of completely regular semigroups in the range of π-regular semigroups. In this paper, Green-relations on GV-semigroups and some congruences on it are studied.

关键词： GV-semigroup GV-inverse semigroup r-semigroup

Determination of Dynamic Load Condition of Aircraft Carrier based on Multivariable Distribution of Flight Parameters

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International Journal of Plant Engineering and Management 2020年第4期25卷 223-237页

作者： JIN Xin LIU Yu zhang jian′gang Strength Design Institute Xi′an Aircraft Design InstituteXi′an 710089China Avionics Systems Design Institute Xi′an Aircraft Design InstituteXi′an 710089China

In order to solve the design problem of dynamic load of a carrier-based aircraft,according to the relevant criteria of national military standards,eight key flight parameters of the dynamic load conditions for the aircraft carrier were *** on the multivariable distribution data of landing flight parameters obtained from flight test,the distribution form and range limitation of each flight parameter were determined by using the probability distribution of each flight parameter and the spatial relationship among ***,100000 sets of data were constructed to simulate the landing condition of aircraft in the form of random *** the envelope is screened by multivariable joint probability distribution,the boundary conditions were compared and merged,and finally the dynamic load conditions were *** this paper,a set of dynamic load condition design method based on the aircraft requirements is constructed,which systematically covers all kinds of situations that occur in the process of aircraft landing,and improves the conventional design process of aircraft dynamic load.

关键词： load condition flight parameter variables probability joint probability

Some Characterizations of Cryptogroups

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Chinese Quarterly Journal of Mathematics 2006年第3期21卷 326-330页

作者： LIU Guo-xin zhang jian-gang Department of Mathematics Southwest University Chongqing 400715 China Department of Mathematics Shanghai Normal University Shanghai 200234 China

In this paper, we give some characterizations of（regular, normal） cryptogroups with Green＇s relations, left（right） translations and homomorphisms.

关键词： cryptogroup Green's relation translation

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管片接头力学解析法:改进条带算法

铁道学报 2013年第3期35卷 102-107页

作者：张建刚何川山东农业大学水利土木工程学院山东泰安271018 西南交通大学土木工程学院四川成都610031

提出能够考虑承压衬垫和端面混凝土共同变形的管片接头理论解析方法的改进条带算法。给出其基本假定、关键公式和求解步骤,最后与经过接头实体试验验证的Betongelenkel公式和三维非线性有限元接头数值模拟结果进行比较,证明该算法结果... 详细信息

提出能够考虑承压衬垫和端面混凝土共同变形的管片接头理论解析方法的改进条带算法。给出其基本假定、关键公式和求解步骤,最后与经过接头实体试验验证的Betongelenkel公式和三维非线性有限元接头数值模拟结果进行比较,证明该算法结果较为可靠。该算法将接头结构体划分为多层,逐层计算,并汇总各层内力和变形,从而解出结构内力和变形关系数值。实现了承压衬垫与混凝土端肋结构共存,能够输入衬垫和混凝土各自非线性材料关系曲线,并能考虑局部接触缝隙和多种接触方式共存等问题,是理论上更加符合管片接头力学实际状态的一种解析算法。

关键词：盾构隧道管片接头力学分析计算方法

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我国钾肥生产发展研究

现代化工 2010年第7期30卷 7-10,12页

作者：张建刚青海盐湖工业集团股份有限公司青海盐湖钾肥销售公司市场部青海格尔木816000

介绍了国内外的钾肥资源现状,对我国钾肥生产发展和资源进行了分析研究,提出了发展对策。

关键词：钾肥资源生产发展研究

层状复合地层条件下管片衬砌结构力学特征模型试验研究

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岩土工程学报 2008年第10期30卷 1537-1543页

作者：何川张建刚杨征西南交通大学地下工程系四川成都610031

针对武汉长江隧道承受高水压和局部区段穿越软硬程度差异极大的层状复合地层的特点,采用盾构隧道–地层复合体模拟试验系统和旋转式水压装置共同作用,完成了在不同水土压力场作用下对层状复合地层和单一地层两种不同地层条件下的管片衬... 详细信息

针对武汉长江隧道承受高水压和局部区段穿越软硬程度差异极大的层状复合地层的特点,采用盾构隧道–地层复合体模拟试验系统和旋转式水压装置共同作用,完成了在不同水土压力场作用下对层状复合地层和单一地层两种不同地层条件下的管片衬砌结构力学特征相似模型试验,并根据试验结果分析了层状复合地层对盾构隧道管片衬砌结构的力学特征的影响。研究表明,随着水压力加大,管片衬砌结构的平均轴力明显增大而最大正负弯矩略有增长或基本不变;处于坚硬岩层包围区域的管片体结构局部弯矩明显减小;小范围的硬岩层对管片衬砌结构整环最大内力影响不大。该研究为武汉长江隧道的管片衬砌结构设计提供有价值的参考。

关键词：盾构隧道相似模型试验层状复合地层管片衬砌结构高水压

农村土地“三权分置”改革将促进农业“第二个飞跃”的实现

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经济纵横 2018年第4期 119-124页

作者：张建刚中国社会科学院马克思主义研究院北京100732

"三权分置"并行的制度安排是继家庭联产承包责任制后农村改革又一重大制度创新。"三权分置"是农村基本经营制度的自我完善,有利于明晰土地产权关系,促进土地资源合理利用,更好维护农民集体、承包农户、经营主体的权益,将加速促进农业"... 详细信息

"三权分置"并行的制度安排是继家庭联产承包责任制后农村改革又一重大制度创新。"三权分置"是农村基本经营制度的自我完善,有利于明晰土地产权关系,促进土地资源合理利用,更好维护农民集体、承包农户、经营主体的权益,将加速促进农业"第二个飞跃"的实现。在"三权分置"改革中,要坚持自愿、不突破政策底线、循序渐进和因地制宜原则。应坚持农村土地公有制不动摇,防止土地私有化;确保农地属性不变更,防止农地的非法开发;鼓励土地适度集中,防止土地集中规模过大。

关键词：三权分置第二个飞跃农业产业经营