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亚马逊棋中评估函数的研究 预览
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作者 陈萱华 杨玲 《电脑知识与技术:学术版》 2019年第3Z期224-226,共3页
机器博弈是人工智能的重要领域,国内外普遍采用棋类作为研究机器博弈技术的载体。以亚马逊棋为载体,总结了实现亚马逊棋机器博弈的几个基本部分,并着重对亚马逊棋对局中用于评定招法优劣的评估函数做了初步研究。在处理评估函数时用到... 机器博弈是人工智能的重要领域,国内外普遍采用棋类作为研究机器博弈技术的载体。以亚马逊棋为载体,总结了实现亚马逊棋机器博弈的几个基本部分,并着重对亚马逊棋对局中用于评定招法优劣的评估函数做了初步研究。在处理评估函数时用到了领地评估特征territory、位置特征position、灵活度特征mobility三个评估特征,并提出使用关于回合数的一次函数加权的计算模型,最后通过实验进行了调参和检验。 展开更多
关键词 亚马逊棋 评估函数 TERRITORY POSITION MOBILITY
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迈向流动性治理:新地域空间的理论重构及其行动策略
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作者 吴越菲 《学术月刊》 CSSCI 北大核心 2019年第2期86-95,共10页
流动社会的来临不仅在根本上冲击着传统的地域假定和治理模式,更是将'地域性'和'流动性'之间的关系问题推向了全球治理变革的前沿地带。20世纪80年代以来,流动性与地域性在地域空间理论的变革中相互关联,并在地域实践... 流动社会的来临不仅在根本上冲击着传统的地域假定和治理模式,更是将'地域性'和'流动性'之间的关系问题推向了全球治理变革的前沿地带。20世纪80年代以来,流动性与地域性在地域空间理论的变革中相互关联,并在地域实践中交织出了全新的治理模式-流动性治理。地域空间理论重新赋予了地域以全面的流动属性,并促动了地域治理的实践变革。流动性治理并非是对'地域'这一治理空间单元的根本性解构,而是形成了一套全新的地域治理范式。 展开更多
关键词 流动性 流动性治理 新地域空间 地域治理
航天试验信息网络战时生存能力研究 预览
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作者 黄雅琳 王宇 《计算机与网络》 2019年第10期62-65,共4页
航天试验信息网络主要面向常规航天科研试验任务,战时生存能力相对有限,不能适应未来战争环境。分析了未来战争的发展趋势,提出航天试验信息网络面对的战场威胁模型,对航天试验信息网络现状及战时生存能力综合分析的基础上,综合运用传... 航天试验信息网络主要面向常规航天科研试验任务,战时生存能力相对有限,不能适应未来战争环境。分析了未来战争的发展趋势,提出航天试验信息网络面对的战场威胁模型,对航天试验信息网络现状及战时生存能力综合分析的基础上,综合运用传输技术、交换技术、网络管理技术和安全保密技术,提出了满足战场环境需求的航天试验信息网络体系架构。 展开更多
关键词 航天试验信息网络 战时生存能力 机动性 抗毁性 抗干扰
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Mobility impact on compensation performance of AMOLED pixel circuit using IGZO TFTs 预览
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作者 Congwei Liao 《半导体学报:英文版》 EI CAS CSCD 2019年第2期33-38,共6页
The suitability of indium gallium zinc oxide(IGZO) thin-film transistors(TFT) for implementation of active matrix display of organic light emitting diodes(AMOLED) compensation pixel circuits is addressed in this paper... The suitability of indium gallium zinc oxide(IGZO) thin-film transistors(TFT) for implementation of active matrix display of organic light emitting diodes(AMOLED) compensation pixel circuits is addressed in this paper. In particular, the impact of mobility on compensating performance for the implementation in AMOLED pixel circuits is investigated. Details of the effective mobility modeling using the power law of gate-to-source voltage are provided, and parameters are extracted according to the measured current-to-voltage data of IGZO TFT samples. The investigated AMOLED pixel circuit consists of 4 switching TFTs, 1 driving TFT, and 1 capacitor. A 'source-follower' structure is used for the threshold voltage extraction of the driving transistor. A new timing diagram is proposed;thus the current error of the pixel circuit is almost independent of the effective mobility. But, to improve the precision of the threshold voltage extraction of the driving transistor, the mobility is required to be greater than5 cm2 V-1 s-1. On the other hand, the optimized storage capacitance is reversely proportional to the effective mobility. Thus, the layout area of the pixel circuit can be decreased from 100 × 100 to 100 × 68 μm2, with the effective mobility increased from 10 to50 cm2 V-1 s-1. Therefore, IGZO TFT is a good alternative backplane technology for AMOLED displays, and a higher effective mobility is preferred for high compensation performance and compact layout. 展开更多
关键词 IGZO TFT PIXEL circuit MOBILITY
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Fe-substituted Ba-hexaaluminate with enhanced oxygen mobility for CO2 capture by chemical looping combustion of methane 预览
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作者 Fei Huang Ming Tian +5 位作者 Yanyan Zhu Xiaodong Wang Aiqin Wang Lin Li Jian Lin Junhu Wang 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第2期50-57,共8页
While Fe-based oxygen carriers(OC) are regarded to be promising for chemical looping combustion(CLC),the decrease of CO2 selectivity during deep reduction process and the severe agglomeration of Fe2O3 often occur afte... While Fe-based oxygen carriers(OC) are regarded to be promising for chemical looping combustion(CLC),the decrease of CO2 selectivity during deep reduction process and the severe agglomeration of Fe2O3 often occur after multiple redox cycles due to the low oxygen mobility.Herein,Fe-substituted Bahexaaluminates(Ba FexAl12– xO19,denoted as BFxA-H,x = 1 and 2) prepared by a modified two-step method exhibited not only higher amount of converted oxygen(Ot) and CH4 conversion(77% and 81% vs.17%and 75%) than those prepared by the traditional co-precipitation method(BFxA-C,x = 1 and 2) but also high CO2 selectivity above 92% during the nearly whole reduction from Fe3+ to Fe2+.Furthermore,the BFxA-H exhibited the excellent recyclability during 50 cycles.The better performance was ascribed to the markedly enhanced oxygen mobility which resulted from dominant occupancy of Fe cations in Al(5) sites(Fe5: 71% and 70% vs.49% and 41%) in mirror planes of hexaaluminate leading to larger amount of lattice oxygen coordinated with Fe5(O–Fe5)(0.45 and 0.85 mmol/g vs.0.31 and 0.50 mmol/g).The improvement of oxygen mobility also favored the preservation of chemical state of Fe cations in hexaaluminate structure in the re-oxidation step,resulting in the excellent recyclability of BFxA-H. 展开更多
关键词 CO2 CAPTURE Chemical LOOPING CH4 conversion Oxygen MOBILITY FE-BASED HEXAALUMINATE
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文化反恐的基本特点研究 预览
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作者 李明 艾恒平 《辽宁公安司法管理干部学院学报》 2019年第1期18-23,共6页
文化反恐是指运用文化进行反恐或者在文化领域进行的反恐斗争,是各种形态反恐斗争的基本构成部分之一。文化恐怖主义具有隐蔽性强和欺骗性大等特点,因此有必要基于理论高度,围绕文化反恐的特点进行深入研究,使人们能够进一步理解文化反... 文化反恐是指运用文化进行反恐或者在文化领域进行的反恐斗争,是各种形态反恐斗争的基本构成部分之一。文化恐怖主义具有隐蔽性强和欺骗性大等特点,因此有必要基于理论高度,围绕文化反恐的特点进行深入研究,使人们能够进一步理解文化反恐的本质,从而筑牢底线,有效防范敌对势力利用文化在意识形态领域进行渗透和破坏,提高人们运用文化进行反恐斗争的能力。 展开更多
关键词 文化反恐 特点 行动力
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右美托咪定复合罗哌卡因甲钴胺混合液治疗肩周炎疗效观察
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作者 任丹凤 曹敏芳 +1 位作者 王冬燕 王芳 《中国预防医学杂志》 CAS CSCD 2019年第4期308-311,共4页
目的观察B超引导下局部注射右美托咪定+罗哌卡因治疗肩周炎的治疗效果。方法选取2015年11月至2017年3月,杭州市萧山区第一人民医院收治的100例肩周炎患者,随机分为治疗组和对照组,每组50例,均采用在B超引导下混合液分别注射于肩岬上神... 目的观察B超引导下局部注射右美托咪定+罗哌卡因治疗肩周炎的治疗效果。方法选取2015年11月至2017年3月,杭州市萧山区第一人民医院收治的100例肩周炎患者,随机分为治疗组和对照组,每组50例,均采用在B超引导下混合液分别注射于肩岬上神经和喙突、岗下肌、小圆肌。治疗组混合液为0.5mg/L右美托咪定+0.1%罗哌卡因+甲钴胺1mg;对照组混合液为0.1%罗哌卡因+甲钴胺1mg。观察治疗后效果从注入药物起开始计时,注射后15min、24h、 1周、1月的效果。比较两组的疗效、NRS疼痛评分、运动阻滞评分、肩关节活动度评分、血流动力学、复发率和再治疗率、不良反应。结果治疗组与对照组相比,治疗组总有效率较高(χ^2=6.06,P<0.05),治疗组NRS疼痛评分低于对照组(P<0.05),关节活动度评分高于治疗组(P<0.05)。治疗组运动阻滞情况优于对照组(Z=12.34,P<0.01)。治疗组复发3例,再治疗3例,对照组复发10例,再治疗11例,对照组复发率和再治疗率均高于治疗组(P<0.05)。两组不良反应发生率比较差异无统计学意义(P>0.05)。结论在疼痛改善,活动度改善等方面右美托咪定组疗效优于对照组,且无明显血流动力学影响。 展开更多
关键词 B超引导 右美托咪定 罗哌卡因 联合治疗 肩周炎 疼痛 活动度
对游动性的反思——评《游牧的终结?——内亚地区社会、国家与环境》 预览
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作者 阿妮尔 《内蒙古社会科学》 CSSCI 北大核心 2019年第2期204-212,共9页
在游牧大量消失的今天,汉弗莱与斯尼思在《游牧的终结?》一书中开创性地提出,作为草原畜牧业的关键技能,保持高度的游动性不仅可以避免草场退化,还可以与现代化、机械化与市场化相结合。汉弗莱等的观点虽然被广泛引述,却一直没有得到深... 在游牧大量消失的今天,汉弗莱与斯尼思在《游牧的终结?》一书中开创性地提出,作为草原畜牧业的关键技能,保持高度的游动性不仅可以避免草场退化,还可以与现代化、机械化与市场化相结合。汉弗莱等的观点虽然被广泛引述,却一直没有得到深入探究。在讨论汉弗莱等所提出的主要观点的同时,结合笔者的田野资料,指出汉弗莱等的研究存在忽略产权与草场退化的深层关联等多方面的局限,并总结了其对后续研究的启示。 展开更多
关键词 草原畜牧业 游动性 草场退化 现代化
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图书馆移动服务使用意愿影响因素实证研究——基于信息安全感知和移动性等变量的技术接受模型 预览 被引量:1
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作者 徐向东 何丹丹 《图书馆》 CSSCI 北大核心 2019年第2期79-85,共7页
文章根据当今移动互联网环境下用户使用图书馆移动服务的具体情景和感知行为深入分析,在TAM理论基础上,充分关注用户泛在化和信息安全感知等新一代信息技术背景下的互联网相关情景因素,并通过实证研究证明了信息安全感知和移动性对用户... 文章根据当今移动互联网环境下用户使用图书馆移动服务的具体情景和感知行为深入分析,在TAM理论基础上,充分关注用户泛在化和信息安全感知等新一代信息技术背景下的互联网相关情景因素,并通过实证研究证明了信息安全感知和移动性对用户感知易用性和感知有用性有重要影响,同时得出了与以往研究不同的观点:网络外部性对感知易用性影响不显著,感知成本对使用意愿影响不显著等。 展开更多
关键词 图书馆移动服务 TAM 信息安全感知 移动性
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Integrating GPS trajectory and topics from Twitter stream for human mobility estimation
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作者 Satoshi MIYAZAWA Xuan SONG +2 位作者 Tianqi XIA Ryosuke SHIBASAKI Hodaka KANEDA 《中国计算机科学前沿:英文版》 SCIE EI CSCD 2019年第3期460-470,共11页
Understanding urban dynamics and large-scale human mobility will play a vital role in building smart cities and sustainable urbanization. Existing research in this domain mainly focuses on a single data source (e.g., ... Understanding urban dynamics and large-scale human mobility will play a vital role in building smart cities and sustainable urbanization. Existing research in this domain mainly focuses on a single data source (e.g., GPS data, CDR data, etc.). In this study, we collect big and heterogeneous data and aim to investigate and discover the relationship between spatiotemporal topics found in geo-tagged tweets and GPS traces from smartphones. We employ Latent Dirichlet Allocation-based topic modeling on geo-tagged tweets to extract and classify the topics. Then the extracted topics from tweets and temporal population distribution from GPS traces are jointly used to model urban dynamics and human crowd flow. The experimental results and validations demonstrate the efficiency of our approach and suggest that the fusion of cross-domain data for urban dynamics modeling is more practical than previously thought. 展开更多
关键词 GPS TRAJECTORY HUMAN MOBILITY SNS locationbased social network (LBSN) TOPIC modeling data mining SPATIOTEMPORAL TOPIC
Terahertz emission from layered GaTe crystal due to surface lattice reorganization and in-plane noncubic mobility anisotropy
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作者 Jiangpeng Dong Kevin-P. Gradwohl +5 位作者 Yadong Xu Tao Wang Binbin Zhang Bao Xiao Christian Teichert Wanqi Jie 《光子学研究:英文版》 CSCD 2019年第5期518-525,共8页
In this work, a model based on the optical rectification effect and the photocurrent surge effect is proposed to describe the terahertz emission mechanism of the layered GaTe crystal. As a centrosymmetric crystal, the... In this work, a model based on the optical rectification effect and the photocurrent surge effect is proposed to describe the terahertz emission mechanism of the layered GaTe crystal. As a centrosymmetric crystal, the optical rectification effect arises from the breaking of the inversion symmetry due to lattice reorganization of the crystal’s surface layer. In addition, the photocurrent surge originating from the unidirectional charge carrier diffusion-due to the noncubic mobility anisotropy within the layers-produces terahertz radiation. This is confirmed by both terahertz emission spectroscopy and electric property characterization. The current surge perpendicular to the layers also makes an important contribution to the terahertz radiation, which is consistent with its incident angle dependence. Based on our results, we infer that the contribution of optical rectification changes from 90%under normal incidence to 23% under a 40° incidence angle. The results not only demonstrate the terahertz radiation properties of layered GaTe bulk crystals, but also promise the potential application of terahertz emission spectroscopy for characterizing the surface properties of layered materials. 展开更多
关键词 GATE CRYSTAL surface lattice REORGANIZATION IN-PLANE noncubic MOBILITY
Stabilization of nanoscale zero-valent iron in water with mesoporous carbon(n ZVI@MC)
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作者 Junming Shi Jing Wang +2 位作者 Wei Wang Wei Teng Wei-xian Zhang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第7期28-33,共6页
Two challenges persist in the applications of nanoscale zero-valent iron(nZVI) for environmental remediation and waste treatment: limited mobility due to rapid aggregation and short lifespan in water due to quick oxid... Two challenges persist in the applications of nanoscale zero-valent iron(nZVI) for environmental remediation and waste treatment: limited mobility due to rapid aggregation and short lifespan in water due to quick oxidation. Herein, we report the nZVI incorporated into mesoporous carbon(MC) to enhance stability in aqueous solution and mobility in porous media. Meanwhile, the reactivity of nZVI is preserved thanks to high temperature treatment and confinement of carbon framework. Small-sized(~16 nm) nZVI nanoparticles are uniformly dispersed in the whole carbon frameworks. Importantly, the nanoparticles are partially trapped across the carbon walls with a portion exposed to the mesopore channels. This unique structure not only is conductive to hold the nZVI tightly to avoid aggregation during mobility but also provides accessible active sites for reactivity. This new type of nanomaterial contains ~10 wt% of iron. The nZVI@MC possesses a high surface area(~ 500 m~2/g) and uniform mesopores(~ 4.2 nm) for efficient pollutant diffusion and reactions. Also, high porosity of nZVI@MC contributes to the stability and mobility of nZVI. Laboratory column experiments further demonstrate that nZVI@MC suspension(~4 g Fe/L) can pass through sand columns much more efficiently than bare nZVI while the high reactivity of nZVI@MC is confirmed from reactions with Ni(II). It exhibits remarkably better performance in nickel(20 mg/L) extraction than mesoporous carbon, with 88.0% and 33.0%uptake in 5 min, respectively. 展开更多
关键词 MESOPOROUS carbon NANOSCALE zero-valent iron MOBILITY Porous media Heavy metal removal
意向性牙再植治疗重度牙周炎患牙的临床研究 预览
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作者 张佳喻 罗宁 +2 位作者 苗棣 应绚 陈悦 《国际口腔医学杂志》 CAS CSCD 2019年第4期400-406,共7页
目的评价意向性牙再植治疗重度牙周炎患牙的临床效果,探索其愈合机制及可能影响预后的因素。方法选取42位重度牙周炎患者的42颗患牙进行意向性牙再植,术后随访18个月,收集其临床和影像资料,采用Wilcoxon秩和检验或配对t检验对数据进行... 目的评价意向性牙再植治疗重度牙周炎患牙的临床效果,探索其愈合机制及可能影响预后的因素。方法选取42位重度牙周炎患者的42颗患牙进行意向性牙再植,术后随访18个月,收集其临床和影像资料,采用Wilcoxon秩和检验或配对t检验对数据进行分析。结果患牙存留率从术后9个月的95.2%降至术后18个月的90.5%;术后9个月的松动度改善率为87.5%;术后18个月固连发生率为76.3%。患牙术后的探诊深度和骨丧失程度有所改善,但是牙龈退缩有一定程度增加,术前术后变化的差异均存在统计学意义(P<0.05)。吸烟者术后疗效较不吸烟者差(P<0.05)。结论意向性牙再植治疗重度牙周炎临床效果良好,牙齿固连可能是一种合理并且重要的术后愈合机制,吸烟应当被列为该治疗的禁忌证。 展开更多
关键词 意向性牙再植 重度牙周炎患牙 松动度 牙齿固连 吸烟
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MX2型二维半导体载流子迁移率理论预测 预览
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作者 何远德 黄志硕 +1 位作者 覃检涛 张文旭 《化学研究与应用》 CAS CSCD 北大核心 2019年第2期239-246,共8页
为找到未来半导体晶体管合适的沟道材料,计算了14种MX2(其中M=Mo,W,Sn,Hf,Zr和Pt,X=S,Se和Te)型二维半导体载流子有效质量、带隙以及电子和空穴迁移率。在计算过程中,为了快速对载流子迁移率进行估计,利用形变势的近似电声耦合矩阵元。... 为找到未来半导体晶体管合适的沟道材料,计算了14种MX2(其中M=Mo,W,Sn,Hf,Zr和Pt,X=S,Se和Te)型二维半导体载流子有效质量、带隙以及电子和空穴迁移率。在计算过程中,为了快速对载流子迁移率进行估计,利用形变势的近似电声耦合矩阵元。计算时考虑长波光学声子和声学声子的散射,而在极化晶体中,考虑了极化散射。计算结果表面,WS2,PtS2以及PtSe2具有最高的电子迁移率以及非零的带隙。其中,PtSe2的电子在室温下的理论迁移率上限为4000cm^2·V^-1·s^-1,而W,Hf和Zr的二维化合物室温时的空穴迁移率较高,其中含W的化合物理论迁移率上限到2600cm^2·V^-1·s^-1。该计算研究为实验合成高迁移率的二维材料提供指导,同时为实验获得高性能以二维材料作为沟道的场效应晶体管提供参考,加速二维材料的应用。 展开更多
关键词 二维半导体 迁移率 形变势
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流动性视角下流动家庭的空间实践和情感重构
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作者 陶伟 蔡少燕 余晓晨 《地理学报》 EI CSSCI CSCD 北大核心 2019年第6期1252-1266,共15页
流动性的增强使迁移活动达到前所未有的广度和强度,'家'的流动日渐成为重要的流动形式,'家'的流动亦成为流动性研究的重要关注点。在新型城镇化进程中,伴随着家庭式迁移的发展浪潮,流动家庭的空间实践和情感重构成为一... 流动性的增强使迁移活动达到前所未有的广度和强度,'家'的流动日渐成为重要的流动形式,'家'的流动亦成为流动性研究的重要关注点。在新型城镇化进程中,伴随着家庭式迁移的发展浪潮,流动家庭的空间实践和情感重构成为一个重要话题。在流动过程中,移民的流动性实践往往赋予了'家'不断转换和流动的意义和内涵。基于流动性理论视角,延循'家'的地理学脉络,选取两个典型的流动家庭案例,通过质性研究方法分析对比其在流动过程中的空间实践及其对'家'的情感建构与重构的影响。研究发现:时间性、空间性和地方性是研究'家的流动性'的重要变量和维度。作为刻画流动性的基础尺标,流动轨迹的多位移空间性和流动过程的多阶段时间性使得'家'的地方性处于一个动态关联的状态。'家'的情感归属、'家'的观念和意义通过'家'的流动和营造实践在解构中被延续与重建。 展开更多
关键词 流动家庭 流动性 家的地理学 空间实践 情感归属
SiC JFET与SiC MOSFET失效模型及其短路特性对比 预览
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作者 周郁明 刘航志 +1 位作者 杨婷婷 陈兆权 《电子学报》 EI CAS CSCD 北大核心 2019年第3期726-733,共8页
建立了两种碳化硅(SiC)器件JFET和MOSFET的失效模型.失效模型是在传统的电路模型的基础上引入了额外附加的泄漏电流,其中,SiC JFET是在漏源极引入了泄漏电流,SiC MOSFET是在漏源极和栅极引入了泄漏电流;同时,为了体现温度和电场强度与... 建立了两种碳化硅(SiC)器件JFET和MOSFET的失效模型.失效模型是在传统的电路模型的基础上引入了额外附加的泄漏电流,其中,SiC JFET是在漏源极引入了泄漏电流,SiC MOSFET是在漏源极和栅极引入了泄漏电流;同时,为了体现温度和电场强度与失效的关系,用与温度和电场强度相关的沟道载流子迁移率代替了传统电路模型所采用的常数迁移率.有关文献的实验结果和半导体器件的计算机模拟(Technology Computer Aided Design,TCAD)验证了两种SiC器件失效模型的准确性.所建立的失效模型能够对比SiC JFET和SiC MOSFET的短路特性. 展开更多
关键词 SIC JFET SIC MOSFET 失效 迁移率 泄漏电流 短路
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Temperature-dependent subband mobility characteristics in n-doped silicon junctionless nanowire transistor
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作者 窦亚梅 韩伟华 +4 位作者 郭仰岩 赵晓松 张晓迪 吴歆宇 杨富华 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期357-360,共4页
We have investigated the temperature-dependent effective mobility characteristics in impurity band and conduction subbands of n-doped silicon junctionless nanowire transistors. It is found that the electron effective ... We have investigated the temperature-dependent effective mobility characteristics in impurity band and conduction subbands of n-doped silicon junctionless nanowire transistors. It is found that the electron effective mobility of the first subband in 2-fold valleys is higher than that of the second subband in 4-fold valleys. There exists a maximum value for the effective subband mobilities at low temperatures, which is attributed to the increase of thermally activated electrons from the ionized donors in the impurity band. The experimental results indicate that the effective subband mobility is temperature-dependent on the electron interactions by thermal activation, impurity scattering, and intersubband scattering. 展开更多
关键词 effective SUBBAND MOBILITY thermal activation COULOMB scattering silicon NANOWIRE TRANSISTOR
Monolayer organic field-effect transistors
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作者 Jie Liu Lang Jiang +2 位作者 Wenping Hu Yunqi Liu Daoben Zhu 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第3期313-330,共18页
Monolayer organic field-effect transistors(OFETs) are attracting worldwide interest in device physics and novel applications due to their ultrathin active layer for two-dimensional charge transport. The monolayer film... Monolayer organic field-effect transistors(OFETs) are attracting worldwide interest in device physics and novel applications due to their ultrathin active layer for two-dimensional charge transport. The monolayer films are generally prepared by thermal evaporation, the Langmuir technique or self-assembly process, etc., but their electrical performance is relatively lower than corresponding thick films. From 2011, the performance of monolayer OFETs has been boosted by using the monolayer molecular crystals(MMCs) as active channels, which opened up a new era for monolayer OFETs. In this review, recent progress of monolayer OFETs, including the preparation of monolayer films, their OFET performance and applications are summarized.Finally, perspectives of monolayer OFETs in the near future are also discussed. 展开更多
关键词 MONOLAYER films organic FIELD-EFFECT TRANSISTORS MONOLAYER molecular crystals(MMCs) MOBILITY
The Identity of nds in Ancient Egypt
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作者 郭小瑞 郭丹形 《世界史研究:英文版》 2019年第1期20-35,共16页
nds as a civilian group,completed the formation of the group through self-identity and the public recognition was as an external feedback of their self-awareness awakening.The life-or-death moment promoted the nds s g... nds as a civilian group,completed the formation of the group through self-identity and the public recognition was as an external feedback of their self-awareness awakening.The life-or-death moment promoted the nds s group cohesion and inspired their group survival consciousness.Therefore,the study of nds can be a good breakthrough and reference for the study of other commoner groups in ancient Egypt. 展开更多
关键词 NDS The Identity SOCIAL Group SELF-IDENTITY SELF-AWARENESS Public Recognition Intergroup Relationship rhyt swa.w hwrw SOCIAL Structure SOCIAL Mobility SOCIAL UNREST SELF-PRESERVATION
Type Synthesis of Lower Mobility Parallel Mechanisms: A Review
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作者 Wei Ye Qinchuan Li 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2019年第2期13-23,共11页
Type synthesis of mechanisms aims to systematically determine all possible structures for a specific mobility requirement. Numerous methods based on di erent theories were proposed for type synthesis of lower mobility... Type synthesis of mechanisms aims to systematically determine all possible structures for a specific mobility requirement. Numerous methods based on di erent theories were proposed for type synthesis of lower mobility parallel mechanisms in past decades. However, there does not exist a comprehensive review on these approaches. Therefore, the goal of this paper is to give such a review, classifying the approaches proposed in the literature into three groups, namely, motion-based methods, constraint-based methods, and other methods. The motion-based methods include the Lie group based method, the GF set method, the linear transformation method, the POC set method,and the finite screw method. The constraint-based methods involve the screw theory-based method, the virtual chain method, the method based on Grassmann line geometry and line graphs, and the motion constraint generator method. Other methods contain the enumeration approach based on the general CGK mobility formula and the graph theory method. Upon thoroughly analyzing the characteristics and/or limitations of each method, this review provides a well reference to help researchers find an e ective synthesis method for innovative design and further scientific investigations for mechanisms. 展开更多
关键词 PARALLEL mechanism LOWER MOBILITY TYPE synthesis INNOVATIVE design
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