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Chinese Physics Letters 2017年第4期34卷 83-86页

作者： han-han lu Jing-Ping Xu lu Liu School of Optical and Electronic Information Huazhong University of Science and Technology Wuhan 430074

The ZrTiON gate-dielectric GaAs metal-oxide-semiconductor （MOS） capacitors with or without ZrAION as the interfacial passivation layer （IPL） are fabricated and their properties are investigated. The experimental results show that the GaAs MOS capacitor with the ZrAION IPL exhibits better interracial and electrical properties, including lower interface-state density （1.14 × 10^12 cm^-2eV^-1）, smaller gate leakage current （6.82 × 10^-5 A//cm^2 at Vfb ＋1V）, smaller capacitance equivalent thickness （1.5 nm）, and larger k value （26）. The involved mechanisms lie in the fact that the ZrAION IPL can effectively block the diffusion of Ti and O towards the GaAs surface, thus suppressing the formation of interracial Ga-/As-oxides and As-As dimers, which leads to improved interracial and electrical properties for the devices.

关键词： MOS Zr Interfacial and Electrical Properties of GaAs Metal-Oxide-Semiconductor Capacitor with ZrAlON as the Interfacial Passivation Lay

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Distrust Prediction in Signed Social Network

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Chinese Journal of Electronics 2019年第1期28卷 188-194页

作者： SHEN Pengfei LIU Shufen han lu College of Computer Science and Technology Jilin University

In social networks, the most studies focus on the trust prediction, but distrust cannot get enough attention. The distinct characteristics of distrust relations present challenges to traditional relation *** relations are very sparse in social network,and negative interaction data is too little. We embark on the problem to investigate the distrust prediction with only network topology. After achieving seven social distrusting-inducing factors, we adopt machine learning and optimization methods to model the prediction *** framework of Distrust prediction in Signed social network(DP-SSN) is proposed, which can predict distrust relations without any interaction data. Empirically, we perform extensive experiments on real-world data to corroborate the effectiveness of the proposed framework.

关键词： Signed network Machine learning Data mining Social networks

Pheromone Model Selection in Ant Colony Optimization for the Travelling Salesman Problem

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Chinese Journal of Electronics 2017年第2期26卷 223-229页

作者： LIU Shufen LENG Huang han lu College of Computer Science and Technology Jilin University

As a meta-heuristic approach,Ant colony optimization(ACO) has many *** the algorithm selection of pheromone models is the top *** pheromone models that don’t suffer negative biases is a natural *** for the travelling salesman problem,the first order pheromone is widely *** come across travelling salesman problem,we study the reasons for the success of ant colony optimization from the perspective of pheromone models,and unify different order pheromone *** tests,we have introduced the concept of sample locations and the similarity coefficient to pheromone *** first order pheromone model and the second order pheromone model are compared and are further *** illustrate that the second order pheromone model has better global search ability and diversity of population than the *** appropriate-scale travelling salesman problems,the second order model performs better than the first order pheromone model.

关键词： Ant colony optimization(ACO) Pheromone model selection The travelling salesman problem

Research on Formal Degree Evaluation and Analysis for Domain Software Based on Evidence

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Chinese Journal of Electronics 2016年第5期25卷 793-800页

作者： BAO Tie LIU Shufen han lu College of Computer Science and Technology Jilin University

Existing researches fail to involve formalized methods in evaluation and analysis of domain software and lack analysis on formal degree, this paper comes up with a formal degree evaluation approach for domain software based on evidence. Various levels of transformation models are mapped by formal analysis of evidence in life cycle of domain software so as to quantitatively measure degree of evidence. Evaluation model based on evidence is established by analyzing detailed evaluation requirement.A level model including mapping condition is established to describe formal degree at hierarchical level. This paper explains detailed evaluation process through an evaluation example. The approach stated in this paper can describe formal degree of domain software, evaluation data can support subsequent bottleneck analysis and trustworthy evolution, thus provide formal support for creditable construction and analysis.

关键词： Software evaluation Domain software Formal degree Evidence metrics

A Hybrid Approach to Maximize Lifetime in Connected Directional Sensor Networks with Adjustable Sensing Ranges

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Chinese Journal of Electronics 2018年第1期27卷 159-167页

作者： LIU Shufen GAO Sihua han lu College of Computer Science and Technology Jilin University

A directional sensor network consists of numerous small sensor nodes that have limited battery power and operate within a restricted sensing range angle. Coverage and connectivity, as two important issues,are widely studied in directional sensor networks. Different from conventional directional sensor nodes in previous studies, those in the present study could adjust their sensing ranges within a range of several values. This paper addresses the Connected adjusted-ranges directional cover(CARDC) problem. The purpose is to organize the directional sensor nodes into a group of connected covers, and assign activities to them, thereby maximizing the network lifetime. We propose a hybrid approach that combines column generation with a genetic algorithm to solve the CARDC problem. The genetic algorithm is utilized to settle the auxiliary problem of column generation, which has the ability to efficiently provide attractive columns for the master problem. Compared with pure integer linear programming formulations, the proposed genetic algorithm significantly improves the speed of column generation method, especially in large-scale networks. The effect variety of number of directions, number of power levels,and communication range on the network lifetime are also investigated.

关键词： Directional sensor networks(DSNs) Coverage and connectivity Column generation Genetic algorithm

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干旱胁迫对胡杨、沙枣幼苗的生理影响

东北林业大学学报 2025年第2期53卷 43-51页

作者：郝瑜张茜马赵群王海珍韩路塔里木大学新疆·阿拉尔843300

筛选高抗逆树种并优化防护林树种配置是解决极端干旱区农田防护林大面积顶梢干枯、衰败的有效途径。以塔里木荒漠乡土树种胡杨、沙枣幼苗为试验材料,采用盆栽控水法研究两树种幼苗抗氧化酶活性、渗透调节物质对干旱胁迫程度、胁迫时间... 详细信息

筛选高抗逆树种并优化防护林树种配置是解决极端干旱区农田防护林大面积顶梢干枯、衰败的有效途径。以塔里木荒漠乡土树种胡杨、沙枣幼苗为试验材料,采用盆栽控水法研究两树种幼苗抗氧化酶活性、渗透调节物质对干旱胁迫程度、胁迫时间的动态响应及抗旱性差异。结果表明:(1)随干旱胁迫程度加剧与胁迫时间延长,胡杨、沙枣叶游离脯氨酸(Pro)质量分数、可溶性蛋白(SP)质量分数、丙二醛(MDA)质量摩尔浓度、叶饱和亏缺及胡杨叶超氧化物歧化酶(SOD)活性均呈增加趋势;两树种幼苗叶过氧化物歧化酶(POD)活性、叶相对含水量呈降低趋势。(2)随干旱胁迫程度加剧,沙枣叶Pro、SP质量分数显著高于胡杨,胡杨叶SOD活性高于沙枣,POD活性相反。胡杨、沙枣幼苗均以Pro、SP维持叶细胞渗透压,并通过SOD清除活性氧(ROS)来协同适应干旱胁迫。(3)综合分析表明沙枣幼苗的抗旱能力优于胡杨幼苗。建议干旱区绿洲农田防护林建设中优先选择沙枣或以沙枣、胡杨为主要树种营建混交林,以及退化防护林改造修复时配置补植沙枣,恢复农田防护林的生态功能。

关键词：抗旱性渗透调节物质保护酶乡土树种

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Algorithms for the Prize-Collecting k-Steiner Tree Problem

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Tsinghua Science and Technology 2022年第5期27卷 785-792页

作者： lu han Changjun Wang Dachuan Xu Dongmei Zhang School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing 100124China School of Computer Science and Technology Shandong Jianzhu UniversityJinan 250101China

In this paper,we study the prize-collecting k-Steiner tree(PCkST) *** are given a graph G=(V,E) and an integer *** graph is connected and undirected.A vertex r ∈ V called root and a subset R?V called terminals are also given.A feasible solution for the PCkST is a tree F rooted at r and connecting at least k vertices in *** a vertex from the tree incurs a penalty cost,and including an edge in the tree incurs an edge *** wish to find a feasible solution with minimum total *** total cost of a tree F is the sum of the edge costs of the edges in F and the penalty costs of the vertices not in *** present a simple approximation algorithm with the ratio of 5.9672 for the *** algorithm uses the approximation algorithms for the prize-collecting Steiner tree(PCST) problem and the k-Steiner tree(kST) problem as *** we propose a primal-dual based approximation algorithm and improve the approximation ratio to 5.

关键词： prize-collecting Steiner tree approximation algorithm

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Modal parameter determination and chatter prediction for blade whirling: a comparative study based on symmetric and asymmetric FRF

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Advances in Manufacturing 2021年第1期9卷 145-159页

作者： lu-Yi han Ri-Liang Liu Xin-Feng Liu School of Mechanical Engineering Shandong UniversityJinan 250061People's Republic of China Key Laboratory of High Efficiency and Clean Mechanical Manufacture Shandong UniversityJinan 250061People's Republic of China National Demonstration Center for Experimental Mechanical Engineering Education Shandong UniversityJinan 250061People's Republic of China

Whirling has been adopted for the cost-effective machining of blade-shape components in addition to traditional end milling and flank milling *** satisfy the requirements of rotary forming in the blade whirling process,the workpiece must be clamped at both ends in suspension and rotated slowly during machining,which complicates the *** study aims to identify the dynamic characteristics within the blade whirling operation and present strategies for stability *** this study,the dynamic characteristics of a whirling system are modeled by assuming symmetric and asymmetric *** prediction frequency response function(FRF)results are compared with experimental ***,semi-discretization stability lobe diagrams(SLDs)obtained using the dynamic parameters of these models are investigated *** results show that the asymmetric model is more suitable for describing the whirling system,whereas the symmetric model presents limitations associated with the frequency range and location of measuring ***,a set of airfoil propeller blade whirling operations is conducted to verify the prediction accuracy.

关键词： Whirling Asymmetric frequency response function(FRF) Stability lobe diagrams(SLD) Semi-discretization method

Parathyroid adenoma combined with a rib tumor as the primary disease: A case report

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World Journal of Clinical Cases 2020年第19期8卷 4681-4687页

作者： lu han Xiao-Feng Zhu College of Medicine Jiamusi UniversityJiamusi 154000Heilongjiang ProvinceChina Department of Thoracic Surgery The First Affiliated Hospital of Jiamusi UniversityJiamusi 154000Heilongjiang ProvinceChina

BACKGROUND Parathyroid adenoma is a benign parathyroid tumor,with serum parathyroid hormone and calcium ion concentrations as the typical basis for *** clinical manifestations are complex and changeable;thus it is easily missed or *** 85%of patients with parathyroid adenoma develop primary hyperparathyroidism,and abnormalities in bones,kidneys and other organs can *** tumors are *** SUMMARY We report a rare case of fibrocystic osteitis associated with a parathyroid adenoma,which was discovered by chance due to a rib *** elevated serum parathyroid hormone and calcium ion were found before *** suspected primary hyperparathyroidism,and color Doppler ultrasound suggested the presence of a thyroid *** informed consent by the patient and her family,we first removed the rib tumor,and one week later,resection of the parathyroid adenoma and thyroid mass was performed on both sides,and the patient recovered well after *** In the case of parathyroid adenoma combined with brown tumor,the bone cyst will gradually decrease in size with time without *** not,surgery should be performed as soon as possible.

关键词： Parathyroid adenoma Rib Brown tumor Primary hyperparathyroidism Treatment Operation Case report

Sensorless Image Based Positioning Control Strategy Design for AFM Systems 36

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Sensorless Image Based Positioning Control Strategy Design f...