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Optically Modulated Bistability in Quantum Dot Resonant Tunneling Diodes

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Chinese Physics Letters 2013年第4期30卷 221-224页

作者： WENG Qian-Chun AN Zheng-Hua HOU Ying zhu zi-qiang Key Laboratory of Polar Materials and Devices(Ministry of Education East China Normal UniversityShanghai 200241 Institute of Advanced Materials and State Key Laboratory of Surface Physics Fudan UniversityShanghai 200433 Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210

InAs quantum dots are introduced into resonant tunneling diodes to study the electronic transport behavior,and a wide bistability(ΔV~0.8 V)is observed in the negative differential resistance *** on an analytic model,we attribute the observed distinct bistability of a resonant tunneling diodes with quantum dots to the feedback dependence of energy of the electron-storing quantum dots on the tunneling current ***,we find that this wide bistable region can be modulated sensitively by light illumination and becomes narrower with increasing light *** results suggest that the present devices can be potentially used as sensitive photodetectors in optoelectronic fields.

关键词： tunneling quantum resonant

Joint inversion of gravity and multiple components of tensor gravity data

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Journal of Central South University 2016年第7期23卷 1767-1777页

作者：鲁光银曹书锦朱自强 School of Geosciences and Info-physics Central South UniversityChangsha 410083China School of Civil Engineering Hunan University of Science and TechnologyXiangtan 411201China Hunan Provincial Key Laboratory of Shale Gas Resource Utilization(Hunan University of Science and Technology) Xiangtan 411201China

Geological structures often exhibit smooth characteristics away from sharp discontinuities. One aim of geophysical inversion is to recover information about the smooth structures as well as about the sharp discontinuities. Because no specific operator can provide a perfect sparse representation of complicated geological models, hyper-parameter regularization inversion based on the iterative split Bregman method was used to recover the features of both smooth and sharp geological structures. A novel preconditioned matrix was proposed, which counteracted the natural decay of the sensitivity matrix and its inverse matrix was calculated easily. Application of the algorithm to synthetic data produces density models that are good representations of the designed models. The results show that the algorithm proposed is feasible and effective.

关键词： hyper-parameter regularization full gravity gradient tensor preconditioned matrix Occam's inversion focusinginversion

Effective grouting area of jointed slope and stress deformation responses by numerical analysis with FLAC^(3D)

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Journal of Coal Science & Engineering(China) 2009年第4期15卷 404-408页

作者： zhu zi-qiang LIU Qun-yi ZENG Fan-he QING Du-gan School oflnfo-Physics Engineering Central South University Changsha 410083 China Highway Management Department of Hunan Changsha 410007 China

To study the grouting reinforcement mechanism in jointed rock slope, first, the theoretical deduction was done to calculate the critical length of slipping if the slope angle is larger than that of joint inclination; Second, the numerical calculation model was founded by FLAG^3D, so as to find the stress and deformation responses of rock mass in the state before and after grouting, the analysis results show that the range between the boundary of critical slipping block and the joint plane that passes the slope toe is the effective grouting area （EGA）. After excavation, large deformation occurs along the joint plane. After grouting, the displacements of rock particles become uniform and continuous, and large deformations along the joint plane are controlled; the dynamic displacement can re- flect the deformation response of slope during excavation in the state before and after grouting, as well as the shear location of potential slip plane. After grouting, the dynamic displacement of each monitoring point reaches the peak value with very few time steps, which indicate that the parameters of the joint plane, such as strength and stiffness, are improved; the stress field becomes uniform. Tensile area reduces gradually; whole stability of the slope and its ability to resist tensile and shear stress are improved greatly.

关键词： slope stress deformation cranny FLAC^3D

Dynamic Pathology and Antigen Location Study on Broiler Breeders with Coinfection of Marek's Disease Virus and Reticuloendotheliosis Virus

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Agricultural Sciences in China 2008年第11期7卷 1387-1393页

作者： DIAO Xiu-guo zhu Guo CHENG zi-qiang WANG Gui-hua MENG Xiang-kai GAO Ting-ting CUI Zhi-zhong College of Animal Science and Veterinary Medicine Shangdong Agricultural University Tai ＇an 271018 P.R. China

To further understand the generation and development of coinfection of Marek＇s disease virus （MDV） and reticuloendotheliosis virus （REV） in broiler breeders, and then find the method and optimal time of differential diagnosis for complex clinic multiple infection, the authors studied the pathohistological changes, apoptosis, immunohistochemistry （immunofluorescence）, and ultrastructure of tumor tissues of broiler breeders inoculated with MDV and REV. The study showed that proliferation of small lymphocytes was seen in the main organs at the age of 1 week, then immature lymphocytes, all kinds of lymphocytes, primitive reticulum cells, and Marek＇s disease cells （MDCs） were observed at 2-9 weeks. Apoptosis of lymphocytes could not be seen until the age of 10 weeks in the immune system. Immunohistochemistry detection showed that the positive signs of MDV and REV antigen were observed in the main organs at 2 weeks of age. Multi-morphology lymphocytes, MDV, and REV, mitotic figures and apoptosis of lymphocytes were observed with the help of transmission electron microscopy. MDV cooperating with REV promotes the course of disease of coinfection. Differential diagnosis can be done by immunohistochemistry in the early stage （before 2 weeks）, and histopathology in the late stage （post 4 weeks）. MDCs, primitive reticulum cells, immature lymphocytes, and two kinds of virions can serve as a basis for bistopathology differential diagnosis.

关键词： Marek's disease virus reticuloendotheliosis virus coinfection dynamic pathology antigen location

Simulation study on ultrasonic tomography for grouted reinforced concrete by finite element

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Journal of Central South University 2015年第7期22卷 2791-2799页

作者：朱自强喻波李亚楠肖嘉莹周勇 School of Geosciences and Info-Physics Engineering Central South University Hunan Chaji Expressway Construction and Development Co. Ltd. College of Resource and Environment and Tourism Hunan University of Arts and Science

A finite element reconstruction algorithm for ultrasound tomography based on the Helmholtz equation in frequency domain is presented to monitor the grouting defects in reinforced concrete *** this algorithm,a hybrid regularizations-based iterative Newton method is implemented to provide stable inverse ***,a dual mesh scheme and an adjoint method are adopted to reduce the computation cost and improve the efficiency of *** reconstruction of both acoustic velocity and attenuation coefficient for a reinforced concrete model is achieved with multiple frequency *** algorithm is evaluated with numerical simulation under various practical scenarios including varied transmission/receiving modes,different noise levels,different source/detector numbers,and different contrast levels between the heterogeneity and background *** obtained suggest that the algorithm is insensitive to noise,and the reconstructions are quantitatively accurate in terms of the location,size and acoustic properties of the target over a range of contrast levels.

关键词： ultrasound computed tomography nondestructive testing concrete exact field finite element method

周作人的“儿童文学”观念的发生——以日本影响为中心

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兰州大学学报（社会科学版） 2019年第6期47卷 72-78页

作者：朱自强中国海洋大学文学与新闻传播学院山东青岛266100

中国儿童文学史的发生是先有理论、后有创作,这一显著特点使得对"儿童文学"观念发生的考察变得尤为重要。周作人是中国儿童文学理论的奠基人。清末民初,他引来西方关于"儿童"的现代观念,建构了"儿童本位"的儿童文学观。"儿童本位""儿童... 详细信息

中国儿童文学史的发生是先有理论、后有创作,这一显著特点使得对"儿童文学"观念发生的考察变得尤为重要。周作人是中国儿童文学理论的奠基人。清末民初,他引来西方关于"儿童"的现代观念,建构了"儿童本位"的儿童文学观。"儿童本位""儿童文学",是两个中国儿童文学发生的关键词语。这两个关键词语在周作人阅读并重视的两本日文书籍《应用于教育的儿童研究》《歌咏儿童的文学》中都出现过,可以推断是周作人直接从日语借用过来的。周作人除了在观念上受到日本的影响,其"儿童本位"的情感也受到了日本文学表现儿童的俳句、小说、随笔的影响。

关键词：周作人儿童儿童本位儿童文学日本

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对中国儿童文学理论研究方法论的思考

东北师大学报（哲学社会科学版） 2006年第1期 80-86页

作者：朱自强中国海洋大学文学院山东青岛266071

作为一门具有独立性的学科,儿童文学拥有自身的研究范畴和自己特有的研究范式。对中国的儿童文学学科建设来说,理论研究的方法论显得尤为重要。建立中国儿童文学理论研究方法论,依然要像五四当年那样,采取“拿来主义”,处理自身问题。... 详细信息

作为一门具有独立性的学科,儿童文学拥有自身的研究范畴和自己特有的研究范式。对中国的儿童文学学科建设来说,理论研究的方法论显得尤为重要。建立中国儿童文学理论研究方法论,依然要像五四当年那样,采取“拿来主义”,处理自身问题。跨学科的儿童文学研究对研究者的理论知识结构有着特殊的要求。一般文学研究的绝大多数方法,都可以运用于儿童文学研究,而具有儿童文学自身特殊性或特效性的研究方法则主要有:儿童哲学的方法;深层心理学的方法;人类文化学的方法;童年历史学的方法。

关键词：儿童文学独立学科方法论拿来主义特效性

网络连接机群上CFD计算的一种负载平衡方法

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航空学报 2005年第2期26卷 129-134页

作者：许正李津朱自强清华大学数学科学系北京100084 北京航空航天大学流体所北京100083

讨论在网络连接的分布式存储并行机群上进行CFD计算的一种负载平衡方法和相关问题。当数值计算的方法是区域分解法时,各节点机上的负载与其处理的子区域的网格节点数成正比,所以同样大小的子区域可保证负载平衡。采用负载再分配即区域... 详细信息

讨论在网络连接的分布式存储并行机群上进行CFD计算的一种负载平衡方法和相关问题。当数值计算的方法是区域分解法时,各节点机上的负载与其处理的子区域的网格节点数成正比,所以同样大小的子区域可保证负载平衡。采用负载再分配即区域再剖分的方法来达到动态负载平衡,构造了一种对多块网格(每块内为结构网格但各块间的连接关系可以是非结构的)进行近似平均分划的方法,并用一种数据结构和算法保证了剖分出的多个子区之间正确的互联和边界信息传递关系。给出了用这种剖分算法对常见多块网格进行分划的例子,并对三维流场进行了实际计算。结果证明本文方法是正确的,能有效地均衡计算负载,达到较理想的并行效率。

关键词：并行计算计算流体力学分区算法负载平衡

AN INVERSE DESIGN METHOD OF TRANSONIC AIRFOIL AND WING

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Chinese Journal of Aeronautics 1993年第3期 157-163页

作者： zhu zi-qiang,Xia Zhi-xun,Wu Li-yi Unstitute of Fluid Mechanics,Beijing University of Aeronautics and Astronautics,Beijing,China,100083)

An inverse design method of transonic airfoil and wing is described, in which the followingmodifications are made for improving convergence and increasing application ability:an artificial viscosity term is added to the integral equation method to increase the abilityof dealing with the shock; a Riegels type of leading edge correction is taken to removethe singularity at the leading edge of the round-nosed airfoil; a smoothing-relaxation procedureis proposed; all coefficients in the equations are integrated in the analytical form. Aregularity condition in closed form for the transonic airfoils is presented. A few design resultsindicate that this method is effective in the transonic airfoil and wing design.

关键词： AN INVERSE DESIGN METHOD OF TRANSONIC AIRFOIL AND WING Design