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Epitaxial growth of large-area and highly crystalline anisotropic ReSe2 atomic layer

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Nano Research 2017年第8期10卷 2732-2742页

作者： Fangfang Cui Xiaobo Li Qingliang Feng Jianbo Yin Lin Zhou Dongyan Liu Kaiqiang Liu Xuexia He xing Liang Shengzhong Liu Zhibin Lei Zonghuai Liu Hailin Peng Jin zhang Jing Kong Hua Xu Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education Shaanxi Key Laboratory for Advanced Energy Devices Shaanxi Engineering Lab for Advanced Energy technology School of Materials Science and Engineering Shaanxi Normal University Xi'an 710119 China Center for Nanochemistry Beijing National Laboratory for Molecular Sciences Key Laboratory for the Physics and Chemistry of Nanodevices College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Department of Electrical Engineering and computer sciences Massachusetts Institute of Technology Cambridge MA 02139 USA School of Chemistry and Chemical Engineering Shaanxi Normal University Xi' an 710119 China

The anisotropic two-dimensional （2D） layered material rhenium disulfide （ReSe2） has attracted considerable attention because of its unusual properties and promising applications in electronic and optoelectronic devices. However, because of its low lattice symmetry and interlayer decoupling, anisotropic growth and out-of-plane growth occur easily, yielding thick flakes, dendritic structure, or flower-like structure. In this stud34 we demonstrated a bottom-up method for the controlled and scalable synthesis of ReSe2 by van der Waals epitaxy. To achieve controllable growth, a micro-reactor with a confined reaction space was constructed by stacking two mica substrates in the chemical vapor deposition system. Within the confined reaction space, the nucleation density and growth rate of ReSe2 were significantly reduced, favoring the large-area synthesis of ReSe2 with a uniform monolayer thickness. The morphological evolution of ReSe2 with growth temperature indicated that the anisotropic growth was suppressed at a low growth temperature （〈600 ℃）. Field-effect transistors employing the grown ReSe2 exhibited p-type conduction with a current ON/OFF ratio up to 10s and a hole carrier mobility of 0.98 cm^2/（V·s）. Furthermore, the ReSe2 device exhibited an outstanding photoresponse to near-infrared light, with responsivity up to 8.4 and 5.1 A/W for 850- and 940-nm light, respectively. This work not only promotes the large-scale application of ReSe2 in high-performance electronic devices but also clarifies the growth mechanism of low-lattice symmetry 2D materials.

关键词： rhenium diselenide (ReSe2) epitaxial growth high crystal quality anisotropy optoelectronics

Contribution of Ambient Air Pollution on Risk Assessment of Type 2 Diabetes Mellitus via Explainable Machine Learning

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维普期刊数据库

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Biomedical and Environmental sciences 2023年第6期36卷 557-560页

作者： DING Zhong Ao zhang Li Ying LI Rui Ying NIU Miao Miao ZHAO Bo DONG Xiao Kang LIU Xiao Tian HOU Jian MAO Zhen xing WANG Chong Jian Department of Epidemiology and Biostatistics College of Public HealthZhengzhou UniversityZhengzhou 450001HenanChina Department of Software Engineering School of Computer and Artificial IntelligenceZhengzhou UniversityZhengzhou 450001HenanChina Department of Statistics University of Illinois at Urbana-ChampaignChampaignU.S.A NHC Key Laboratory of Prevention and Treatment of Cerebrovascular Diseases Zhengzhou 450001HenanChina

Type 2 diabetes mellitus(T2DM)is recognized as a heterogeneous and complicated disease that is able to influence individuals at various life stages[1].Apart from traditional predictors such as age,family history of diabetes,body mass index,and so on,ambient air pollution is also shown to increase the risk of T2DM in previous studies.

关键词： T2DM Diabetes diabetes

Automated detection on the security of the linked-list operations

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Frontiers of computer science 2022年第2期16卷 170-172页

作者： Hongyu KUANG Jian WANG Ruilin LI Chao FENG YunFei SU xing zhang college of Electronic science and technology National University of Defense TechnologyChangsha 410073China

1 Introduction As measures taken by OS(operation system)to mitigate exploit getting more perfect,the stack-related vulnerabilities are reduced gradually and heap-related vulnerabilities have become increasingly prominent in most C/C++memory *** is known,software program is a fusion of data structures and ***,if unsafe operations are performed on data,unintended results may occur.

关键词： operations perfect system

dentification of blasting vibration and coal-roc fracturing microseismic signals

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Applied Geophysics 2018年第2期15卷 280-289,364页

作者： zhang xing-Li Jia Rui-Sheng Lu Xin-Ming Peng Yan-Jun Zhao Wei-Dong college of computer science and Engineering Shandong University of Science and Technology Qingdao 266590 China Shandong Province Key Laboratory of Wisdom Mine Information technology Shandong University of Science andTechnology Qingdao 266590 China

A new method based on variational mode decomposition （VMD） is proposed to distinguish between coal-rock fracturing and blasting vibration microseismic signals. First, the signals are decomposed to obtain the variational mode components, which are ranked by frequency in descending order. Second, each mode component is extracted to form the eigenvector of the energy of the original signal and calculate the center of gravity coefficient of the energy distribution plane. Finally, the coal-rock fracturing and blasting vibration signals are classified using a decision tree stump. Experimental results suggest that VMD can effectively separate the signal components into coal-rock fracturing and blasting vibration signals based on frequency. The contrast in the energy distribution center coefficient after the dimension reduction of the energy distribution eigenvector accurately identifies the two types of microseismic signals. The method is verified by comparing it to EMD and wavelet packet decomposition.

关键词： Coal-rock fracturing microseismic blasting vibration variational modedecomposition signal identification

APC/Asef多肽抑制剂结构的优化及生物学活性研究

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上海交通大学学报（医学版） 2018年第10期38卷 1139-1144页

作者：钱金星张健上海交通大学基础医学院细胞分化与凋亡教育部重点实验室上海200025

目的·设计并合成结肠腺瘤息肉易感基因(adenomatous polyposis coli,APC)/鸟苷酸交换因子(APC-stimulated guanine nucleotide exchange factor,Asef)多肽抑制剂,探讨该抑制剂不同构效之间的关系。方法·基于APC-MAI-150复合物结构,一方面在MAI-150多肽N端用3-苯基丙酰(3-phenylpropane)、Glu-Glu(GG)和β-Ala-Ala(β-AA)取代连氨基基团苄氧羰基(carbobenzoxy,CBZ),另一方面尝试将MAI-150中N端第6位Tyr侧链苯环上的对位羟基替换为-CN、-NO_2、-NH_2和-F,设计合成新的7条多肽。荧光偏振活性检测多肽亲和力,并根据活性结果将多肽MDL-3、MDL-4和MDL-5对接到APC蛋白中,联合计算机对接的多肽和APC蛋白的结合模式,探讨该3条多肽的构效关系。结果·新合成的7条多肽中,多肽MDL-5的N端3-phenylpropane连氨基亲和力最高,其半数有效抑制浓度(half maximal inhibitory concentration,IC50)为2.35μmol/L;与MDL-5相比,多肽N端用GG(MDL-6)和β-AA(MDL-7)连接氨基亲和力明显降低;MDL-3和MDL-4的N端第6位Tyr侧链苯环上的对位羟基替换为-NH_2和-F亲和力相比较于替换为-CN(MDL-1)和-NO_2 (MDL-2)要明显提高;但新合成的多肽亲和力均低于MAI-150。结论·改造多肽N端连氨基基团和第6位Tyr侧链苯环上的对位羟基无助于提高多肽的亲和力。

关键词：结肠腺瘤息肉易感基因/鸟苷酸交换因子多肽抑制剂构效关系

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信鸽竞翔系统的设计和实现

西南民族大学学报（自然科学版） 2005年第1期31卷 129-133页

作者：陈良银张靖宇游洪跃田星叶大华四川大学计算机学院成都610064 核工业西南物理研究院成都610041

信鸽竞赛活动日见增多,信鸽比赛的管理开始采用自动管理系统.介绍了信鸽竞翔系统的基本设计思想,并给出了系统的软、硬件设计及实现框图.

关键词：信鸽竞翔读卡主机射频卡嵌入式系统

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结合瓶颈特征的注意力声学模型

计算机科学 2019年第1期46卷 260-264页

作者：龙星延屈丹张文林解放军信息工程大学信息系统工程学院郑州450001

目前基于注意力机制的序列到序列声学模型成为语音识别领域的研究热点。针对该模型训练耗时长和鲁棒性差等问题,提出一种结合瓶颈特征的注意力声学模型。该模型由基于深度置信网络(Deep Belief Network,DBN)的瓶颈特征提取网络和基于注... 详细信息

目前基于注意力机制的序列到序列声学模型成为语音识别领域的研究热点。针对该模型训练耗时长和鲁棒性差等问题,提出一种结合瓶颈特征的注意力声学模型。该模型由基于深度置信网络(Deep Belief Network,DBN)的瓶颈特征提取网络和基于注意力的序列到序列模型两部分组成:DBN能够引入传统声学模型的先验信息来加快模型的收敛速度,同时增强瓶颈特征的鲁棒性和区分性;注意力模型利用语音特征序列的时序信息计算音素序列的后验概率。在基线系统的基础上,通过减少注意力模型中循环神经网络的层数来减少训练的时间,通过改变瓶颈特征提取网络的输入层单元数和瓶颈层单元数来优化识别准确率。在TIMIT数据库上的实验表明,该模型在测试集上的音素错误率降低至了17.80%,训练的平均迭代周期缩短了52%,训练迭代次数由139减少至89。

关键词：声学模型注意力模型瓶颈特征深度置信网络

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面向模糊逻辑控制的移动群智感知多任务分配

小型微型计算机系统 2020年第10期41卷 2068-2074页

作者：杨桂松张杨林何杏宇上海理工大学光电信息与计算机工程学院上海200093 上海理工大学出版印刷与艺术设计学院上海200093

移动群智感知是一种新兴的感知范例,它采用参与者携带的移动设备感知实时信息.目前有关任务分配的大多数研究都缺乏计算实际参与者密度并对其进行详细分析的方法.在本文中,首先,基于参与者的出行时间和空间,采用模糊逻辑控制方法得到不... 详细信息

移动群智感知是一种新兴的感知范例,它采用参与者携带的移动设备感知实时信息.目前有关任务分配的大多数研究都缺乏计算实际参与者密度并对其进行详细分析的方法.在本文中,首先,基于参与者的出行时间和空间,采用模糊逻辑控制方法得到不同时空的参与者密度.另外,根据参与者密度,我们可以计算在特定时空下的任务所需要的有效样本数量.然后,本文通过考虑任务的属性和参与者方因素,可以获得所有任务的效用.最后,本文提出了一种全局贪婪算法来分配任务,以确保最大化所有任务的效用.仿真结果表明,在不同时空的任务数量、参与者数量以及参与者承载的最大工作负载的情况下,本文提出的全局贪婪算法在最大化所有任务的效用方面均优于其他基准算法.

关键词：移动群智感知参与者密度模糊逻辑全局贪婪

Five Basic Types of Insider DoS Attacks of Code Dissemination in Wireless Sensor Networks

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International Journal of Communications, Network and System sciences 2009年第1期2卷 64-72页

作者： Yu zhang xing She ZHOU Yi Ming JI Yee Wei LAW Marimuthu PALANISWAMI college of Engineering and computer science Australian National University Canberra ACT Australia Department of Electrical and Electronic Engineering the University of Melbourne Parkville VIC Australia School of computer science Northwestern Polytechnical University Xi’an Shaanxi China

Code dissemination is one of the important services of wireless sensor networks (WSNs). Securing the process of code dissemination is essential in some certain WSNs applications, state-of-the-art secure code dissemination protocols for WSNs aim for the efficient source authentication and integrity verification of code image, however, due to the resource constrains of WSNs and the epidemic behavior of the code dissemination system, existing secure code dissemination protocols are vulnerable to Denial of Service (DoS) attacks when sensor nodes can be compromised (insider DoS attacks). In this paper, we identify five different basic types of DoS attacks exploiting the epidemic propagation strategies used by Deluge. They are (1) Higher-version Advertisement attack, (2) False Request attack, (3) Larger-numbered Page attack, (4) Lower-version Adv attack, and (5) Same-version Adv attack. Simulation shows these susceptibilities caused by above insider DoS attacks. Some simple models are also proposed which promote understanding the problem of insider DoS attacks and attempt to quantify the severity of these attacks in the course of code dissemination in WSNs.

关键词： Sensor Networks Code Dissemination Deluge Security DoS Attacks