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Introduction to the CDEX experiment

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Frontiers of physics 2013年第4期8卷 412-437页

作者： Ke-jun kang Department of Engineering Physics Tsinghua University Beijing 100084

It is believed that weakly interacting massive particles （WIMPs） are candidates for dark matter （DM） in our universe which come from outer space and might interact with the standard model （SM） matter of our detectors on the earth. Many collaborations in the world are carrying out various experiments to directly detect DM particles. China Jinping underground Laboratory （CJPL） is the deepest underground laboratory in the world and provides a very promising environment for DM search. China Dark matter EXperiment （CDEX） is going to directly detect the WIMP flux with high sensitivity in the low WIMP-mass region. Both CJPL and CDEX have achieved a remarkable progress in recent three years. CDEX employs a point-contact germanium （PCGe） semi-conductor detector whose energy threshold is less than 300 eV. In this report we present the measurement results of muon flux, monitoring of radioactivity and radon concentration carried out in CJPL, as well describing the structure and performance of the 1 kg-PCGe detector in CDEX-1 and 10 kg- PCGe detector array in CDEX-10 including the detectors, electronics, shielding and cooling systems. Finally we discuss the physics goals of CDEX-1, CDEX-10 and the future CDEX-1T experiments.

关键词： China Dark matter EXperiment (CDEX) dark matter poit-contact germanium detector China Jinping underground Laboratory (CJPL)

Distribution of Equilibrium Free Energies in a Thermodynamic System with Broken Ergodicity

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Communications in Theoretical Physics 2008年第3期49卷 659-664页

作者： ZHOU Hai-jun LI kang Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China

At low temperatures the configurational phase space of a macroscopic complex system （e.g., a spin-glass） of N - 10^23 interacting particles may split into an exponential number Ωs - exp（const × N） of ergodic sub-spaces （thermodynamic states）. It is usually assumed that the equilibrium collective behavior of such a system is determined by its ground thermodynamic states of the minimal free-energy density, and that the equilibrium free energies follow the distribution of exponentied decay. But actually for some complex systems, the equilibrium free-energy values may follow a Gaussian distribution within an intermediate temperature range, and consequently their equilibrium properties are contributed by excited thermodynamic states. Based on this analysis, the re-weighting parameter y in the cavity approach of spin-glasses is easily understood. Depending on the free-energy distribution, the optimal y can either be equal to or be strictly less than the inverse temperature β.

关键词： free-energy distribution spin-glass thermodynamic state cavity approach broken ergodicity

A synthesizing control model of networked control systems to guarantee QoP and QoS

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控制理论与应用（英文版） 2008年第4期6卷 379-384页

作者： jun kang Guanzhong DAI College of Automation Northwestern Polytechnical University Xi＇an Shannxi 710072 China

The whole performance of the networked control system （NCSs） depends on two interaction factors, namely the quality of control performance （QoP） and quality of network service （QoS）. So, to optimize the whole perfor-mance of NCSs, the problem of guaranteeing QoP and QoS plays an important role in the design of NCSs. However, up to now, little work has been done in this field. In this paper, a synthesizing control model of NCSs to guarantee QoP and QoS is proposed, and a feasible condition of optimizing whole performance of NCSs is also suggested. Finally, the simulation results show that the proposed model is effective.

关键词： Networked control system (NCSs) Synthesizing control Quality of control performance (QoP) Quality of network service (QoS)

Effects of deforestation on microbial diversity in a Siberian larch(Larix sibirica) stand in Mongolia

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Journal of Forestry Research 2019年第5期30卷 1885-1893页

作者： jun Won kang Yeong Dae Park Division of Forest Tree Improvement National Institute of Forest ScienceSuwonGyeonggi 16631Republic of Korea Department of Forest Resources Daegu UniversityGyeongbuk 38453Republic of Korea

For evaluating microbial community changes in a Siberian larch stand disturbed by forest fire or clearcutting,357 clones were randomly selected and sequenced using a culture-independent approach and 16S rRNA sequencing to characterize the bacterial composition and diversity from the different disturbed Siberian larch ***,the burned larch stand had an increase in the relative amounts of b-proteobacteria and Firmicutes and a decrease in Acidobacteria,while Gemmatimonadetes increased Verrucomicrobia decreased in the harvested larch *** diversity and richness were higher in the undisturbed larch stand than the disturbed(burned or clear-cut)larch stands,and the influence of clear-cutting was more negative than that of the forest *** study indicates that evaluating the microbial diversity of undisturbed,burned,and clear-cutting Siberian larch stands provides information about the impact of forest disturbances on soil microbial communities,which may be helpful for understanding and evaluating soil health and devising reafforestation strategies for larch.

关键词： Forest fire Forest health Harvest Microbial diversity Reafforestation Siberian Larch(Larix sibirica) Soil microbiome

基于Unity3d的电气实验教学平台的设计与实现

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天津理工大学学报 2025年第1期41卷 104-111页

作者：康军张鹏李晓飞天津理工大学电气工程与自动化学院

针对传统电气实验教学中长期存在且尚未得到有效解决的问题，以电气专业知识为基础，以VR眼镜为设备载体，以Unity3d为开发平台，通过电气技术和虚拟现实技术的有效结合设计开发出一种基于Unity3d的电气实验教学平台。该平台使用Maya建... 详细信息

针对传统电气实验教学中长期存在且尚未得到有效解决的问题，以电气专业知识为基础，以VR眼镜为设备载体，以Unity3d为开发平台，通过电气技术和虚拟现实技术的有效结合设计开发出一种基于Unity3d的电气实验教学平台。该平台使用Maya建模软件进行三维建模，利用Unity3d中功能强大的系统和灵活的C#脚本语言编程实现人机交互效果，在此平台上开发的电动机运行实验，使学生不仅可以完成电动机接线、运行、过载等基础实验，还可以在保障用电安全的前提下进行任意操作，模拟电路短路、电机损坏等事故的发生，情景化感受事故后果。该电气实验教学平台的优势主要体现在低实验成本运行、高安全系数操作、创新教学模式和提升教学效率上，在学生提升相应工程技能的同时，不断创新电气实验教学模式，实现高质量教学产出。

关键词：虚拟现实 Unity3d 实验教学电气专业

Advances and challenges in DFT-based energy materials design

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Chinese Physics B 2022年第10期31卷 34-52页

作者： jun kang Xie Zhang Su-Huai Wei Beijing Computational Science Research Center Beijing 100193China

The growing worldwide energy needs call for developing novel materials for energy *** initio density functional theory(DFT)calculations allow the understanding and prediction of material properties at the atomic scale,thus,play an important role in energy materials *** to the fast progress of computer power and development of calculation methodologies,DFT-based calculations have greatly improved their predictive power,and are now leading to a paradigm shift towards theory-driven materials *** aim of this perspective is to introduce the advances in DFT calculations which accelerate energy materials *** first present state-of-the-art DFT methods for accurate simulation of various key properties of energy *** we show examples of how these advances lead to the discovery of new energy materials for photovoltaic,photocatalytic,thermoelectric,and battery *** challenges and future research directions in computational design of energy materials are highlighted at the end.

关键词： density functional theory materials design energy applications

NANOFIBROUS MATS WITH BIRD'S NEST PATTERNS BY ELECTROSPINNING

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Chinese Journal of Polymer Science 2012年第1期30卷 130-137页

作者： Xiang-yu Ye Xiao-jun Huang Zhi-kang Xu MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Electrospun material with bio-inspired ordered architectures and patterns is very interesting,yet remains a *** report here that nanofibrous mats with bird＇s nest patterned structures can be directly electrospun from chlorinated polypropylene solutions doped with an ionic *** solution viscosity and the ionic liquid content are two dominant factors to influence the topological morphology of the nanofibrous *** patterned structures can be further modulated by the collection time of electrospinning,the humidity of environment and the design of *** suggest the electrostatic repulsion between the residual charges of the mat surface and the upcoming nanofibers plays a key role in the formation of the bird＇s nest patterns.

关键词： Electrospinning Ionic liquid Patterned structures

Finger vein recognition using weighted local binary pattern code based on a support vector machine

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第7期11卷 514-524页

作者： Hyeon Chang LEE Byung jun kang Eui Chul LEE kang Ryoung PARK Division of Electronics and Electrical Engineering Dongguk University Electronics and Telecommunications Research Institute Division of Fusion and Convergence of Mathematical Sciences the National Institute for Mathematical Sciences

Finger vein recognition is a biometric technique which identifies individuals using their unique finger vein patterns. It is reported to have a high accuracy and rapid processing speed. In addition, it is impossible to steal a vein pattern located inside the finger. We propose a new identification method of finger vascular patterns using a weighted local binary pattern (LBP) and support vector machine (SVM). This research is novel in the following three ways. First, holistic codes are extracted through the LBP method without using a vein detection procedure. This reduces the processing time and the complexities in detecting finger vein patterns. Second, we classify the local areas from which the LBP codes are extracted into three categories based on the SVM classifier: local areas that include a large amount (LA), a medium amount (MA), and a small amount (SA) of vein patterns. Third, different weights are assigned to the extracted LBP code according to the local area type (LA, MA, and SA) from which the LBP codes were extracted. The optimal weights are determined empirically in terms of the accuracy of the finger vein recognition. Experimental results show that our equal error rate (EER) is significantly lower compared to that without the proposed method or using a conventional method.

关键词： Finger vein recognition Support vector machine (SVM) Weight Local binary pattern (LBP)

ROP11 GTPase is a Negative Regulator of Multiple ABA Responses in Arabidopsis

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Journal of Integrative Plant Biology 2012年第3期54卷 169-179页

作者： Zixing Li jun kang Ning Sui Dong Liu MOE Key Laboratory of Bioinformatics School of Life Sciences Tsinghua University Beijing 100084 China

The phytohormone abscisic acid （ABA） plays crucial roles in plant development and plant responses to environmental stresses. Although ABA receptors and a minimal set of core molecular components have recently been discovered, understanding of the ABA signaling pathway is still far from complete. In this work, we characterized the function of ROP11, a member of the plant-specific ROP small GTPases family, in the ABA signaling process. ROP11 is preferentially expressed in guard cells in all plant organs with stomata. Expression of a constitutively active ROP11 （CA-ROP11） suppresses ABA-mediated responses, whereas reduced expression of ROP11 or expression of its dominant-negative form （DN-ROP11） causes the opposite phenotypes. The affected ABA-mediated responses by ROP11 include seed germination, seedling growth, stomatal closure, induction of ABA-responsive genes, as well as plant response to drought stress. Furthermore, we showed that ROP11 and its closest-related family member, ROP10, act in parallel in mediating these responses. ABA treatment does not affect ROP11 transcription and protein abundance; however, it causes the accumulation of CA-ROP11 in the nucleus. These results demonstrated that ROP11 is a negative regulator of multiple ABA responses in Arabidopsis.

关键词： ROP11 GTPase ABA responses negative regulator rop10rop1 double mutant Arabidopsis.