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信息产业集群结构形态及其运行效率分析

情报科学 2008年第5期26卷 657-661页

作者：娄策群王方华中师范大学信息化与信息资源管理研究中心湖北武汉430079

首先从产品种类和企业性质两个不同角度认真分析了信息产业集群的基本结构形态,并在此基础上提出了当前信息产业集群所具有的四类综合结构形态,其次对处于不同综合结构形态下的信息产业集群运行效率分别从成本、规模经济、范围经济以及... 详细信息

首先从产品种类和企业性质两个不同角度认真分析了信息产业集群的基本结构形态,并在此基础上提出了当前信息产业集群所具有的四类综合结构形态,其次对处于不同综合结构形态下的信息产业集群运行效率分别从成本、规模经济、范围经济以及技术创新等角度加以分析比较,同时也指出信息产业集群结构形态的形成主要受到的相关影响因素,并明确指出了有利于我国信息产业集群长期可持续发展的结构形态。

关键词：产业集群信息产业集群结构形态运行效率

绿色石化易燃易爆气体监测系统原位在线校准装置的研制

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计量与测试技术 2024年第2期51卷 64-65,68页

作者：周梦娜虞宵刘欢洪辉张春娥穆寅锋舟山市质量技术监督检测研究院

本文基于动态配气原理和自动控制技术的研究,研制易燃易爆气体监测系统原位在线校准装置,通过设计动态配气模块、供电模块、自动控制模块、通讯模块,实现气体流量动态精确控制、不同浓度标准气体的自动配制、软件自动控制,以及数据的通... 详细信息

本文基于动态配气原理和自动控制技术的研究,研制易燃易爆气体监测系统原位在线校准装置,通过设计动态配气模块、供电模块、自动控制模块、通讯模块,实现气体流量动态精确控制、不同浓度标准气体的自动配制、软件自动控制,以及数据的通讯、处理和管理。结果表明:该装置可靠有效,满足易燃易爆气体监测系统原位在线校准需求。

关键词：绿色石化易燃易爆气体在线校准

三维虚拟仿真牙周病患者病例库在牙周病学前期教学中的应用

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中华医学教育杂志 2024年第5期44卷 349-352页

作者：孙雨哲王宪娥张芮初潘朗新侯建霞北京大学医学部北京100081 北京大学口腔医学院·口腔医院牙周科国家口腔医学中心国家口腔疾病临床医学研究中心口腔生物材料和数字诊疗装备国家工程研究中心口腔数字医学北京市重点实验室北京100081

目的探讨三维虚拟仿真牙周病患者病例库在牙周病学前期教学中的应用效果。方法选择即将进入牙周病学临床实习的北京大学2018级八年制口腔医学专业30名学生作为研究对象,采用随机数字表法将其分为试验组和对照组,每组15名学生。试验组学... 详细信息

目的探讨三维虚拟仿真牙周病患者病例库在牙周病学前期教学中的应用效果。方法选择即将进入牙周病学临床实习的北京大学2018级八年制口腔医学专业30名学生作为研究对象,采用随机数字表法将其分为试验组和对照组,每组15名学生。试验组学生接受三维虚拟仿真牙周病患者病例库教学,对照组学生接受传统教学,并在考核前熟悉该病例库。培训结束后,利用该病例库对两组学生进行临床接诊能力考核,并由系统进行评分;学生接受考核后通过问卷调查收集其对该病例库的评价。采用t检验比较两组学生评分之间差异。结果试验组学生病史采集评分[(52.67±16.24)分],高于对照组学生的[(36.80±10.84)分],其差异具有统计学意义(t=3.15,P=0.004)。问卷调查结果显示,试验组和对照组的15名学生中,所有学生都完全同意或同意该病例库能够提升牙周临床接诊能力和接诊信心。结论三维虚拟仿真牙周病患者病例库有助于提高口腔医学专业学生的牙周病临床接诊能力,并且得到了学生的广泛认可,可以在前期实习中进一步推广应用。

关键词：虚拟仿真牙周病学病例库前期教学

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长江流域膨胀土工程地质特征及工程处理

人民长江 2005年第3期36卷 13-15,28页

作者：刘特洪水利部长江勘测技术研究所湖北武汉430011

膨胀土含有较高蒙脱石类粘土矿物和存在较多裂隙软弱面,湿度变化时发生膨胀或收缩,强度衰减引起建筑物破坏。长江流域Ⅱ、Ⅲ级阶地,山间盆地及低丘缓坡地带广泛分布不同时代和不同成因类型的膨胀土。影响膨胀土强度的因素较多,如湿度、... 详细信息

膨胀土含有较高蒙脱石类粘土矿物和存在较多裂隙软弱面,湿度变化时发生膨胀或收缩,强度衰减引起建筑物破坏。长江流域Ⅱ、Ⅲ级阶地,山间盆地及低丘缓坡地带广泛分布不同时代和不同成因类型的膨胀土。影响膨胀土强度的因素较多,如湿度、钙质结核、矿物成分与游离氧化物、裂隙发育程度等。因此,非饱和膨胀土的工程地质研究和原型监测,在工程建设中是很重要的,研究成果可以用来解决工程实际问题。

关键词：膨胀土工程地质特征原型监测工程处理长江流域

Deducing cascading failures caused by cyberattacks based on attack gains and cost principle in cyber-physical power systems

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Journal of Modern Power Systems and Clean energy 2019年第6期7卷 1450-1460页

作者： Yufei WANG Yanli LIU Jun’e LI Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of EducationSchool of Cyber Science and EngineeringWuhan UniversityWuhan 430072China Global energy Interconnection Research Institute Co.Ltd Beijing 102209China Key Laboratory of Smart Grid of Ministry of education Tianjin UniversityTianjin 300072China

To warn the cascading failures caused by cyberattacks(CFCAs)in real time and reduce their damage on cyber-physical power systems(CPPSs),a novel early warning method based on attack gains and cost principle(AGCP)is ***,according to the CFCA characteristics,the leading role of attackers in the whole evolutionary process is *** breaking out of a CFCA is deduced based on the AGCP from the view of attackers,and the priority order of all CFCAs is then ***,the method to calculate the probability of CFCAs is proposed,and an early warning model for CFCA is ***,to verify the effectiveness of this method,a variety of CFCAs are simulated in a local CPPS model based on the Ieee 39-bus *** experimental results demonstrate that this method can be used as a reliable assistant analysis technology to facilitate early warning of CFCAs.

关键词： Cyber-physical power system Cascading failure Cyberattack early warning Fault probability Attack gains and cost principle Attack route choice

等离子体密度调控CrN薄膜结构改性Ti6Al4V双极板

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表面技术 2022年第4期51卷 194-201,210页

作者：杜峰周艳文王英涵方方张开策粟志伟徐帅王鼎辽宁科技大学材料与冶金学院表面工程研究所辽宁鞍山114051

目的满足质子交换膜燃料电池双极板的使用要求。方法采用热丝增强等离子体磁控溅射技术,通过改变热丝放电电流调控溅射等离子体密度,在Ti6Al4V(TC4)合金表面制备了氮化铬(CrN)薄膜。结果随着热丝放电电流从0 A增加至32 A,真空腔内等离... 详细信息

目的满足质子交换膜燃料电池双极板的使用要求。方法采用热丝增强等离子体磁控溅射技术,通过改变热丝放电电流调控溅射等离子体密度,在Ti6Al4V(TC4)合金表面制备了氮化铬(CrN)薄膜。结果随着热丝放电电流从0 A增加至32 A,真空腔内等离子体密度增强,‒50 V偏压下基体偏流密度从0.07 mA/cm^(2)增至0.7 mA/cm^(2)。CrN薄膜择优取向从低应变能的(111)转变成表面能更低的(200)择优取向。薄膜表面形貌由较疏松的四棱锥型转变成致密球形;无热丝时,CrN薄膜显示有铬的(110)衍射峰且铬原子数分数为52.16%,为富金属薄膜。热丝放电电流为16 A和32 A时,CrN薄膜中的铬原子数分数分别降至50.79%和49.82%,且无Cr的衍射峰,即逐渐转变为贫铬。采用热丝辅助磁控溅射,将使氮气离化率增大,活性增强,引起薄膜贫铬。模拟双极板工作环境下,与TC4腐蚀电流密度1.5×10^(‒8) A/cm^(2)相比,CrN薄膜的腐蚀电流密度由无热丝的3×10^(‒5) A/cm^(2)降至使用热丝的9×10^(‒9) A/cm^(2)。对电化学阻抗谱拟合等效电路表明,无热丝放电电流条件下制备的CrN薄膜等效电路中出现了基体与涂层间的电阻,说明疏松涂层为腐蚀液提供了通道,在基体和涂层间形成了腐蚀。16 A和32 A热丝放电电流条件下制备的CrN薄膜与表面无涂层的钛合金等效电路相同,说明致密涂层能有效阻碍腐蚀介质的渗入,具有最佳腐蚀抗性。无热丝放电电流时接触电阻为7.95 mΩ·cm^(2),热丝放电电流16 A时接触电阻增至15.65 mΩ·cm^(2),32 A时接触电阻大幅增加。结论在质子交换膜燃料电池双极板备选材料钛合金表面制备致密CrN薄膜,增强了基体的耐蚀性,但贫铬组分导致薄膜电阻增大。在钛合金电极板表面制备致密且略富金属或化学剂量比相当的CrN薄膜,将满足其作为燃料电池双极板的使用条件。

关键词： TC4钛合金双极板磁控溅射等离子体密度 CrN薄膜腐蚀抗性

Novel heating-and deformation-induced phase transitions and mechanical properties for multicomponent Zr_(50)M_(50),Zr_(50)(M,Ag)_(50)and Zr_(50)(M,Pd)_(50)(M=fe,Co,Ni,Cu)amorphous alloys

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Journal of Materials Science & technology 2022年第9期104卷 109-118页

作者： J.Ding A.Inoue F.L.Kong S.L.Zhu Y.L.Pu e.Shalaan A.A.Al-Ghamdi A.L.Greer School of Materials Science and engineering Tianjin UniversityTianjin 300072China International Institute of Green Materials Josai International UniversityTogane 283-8555Japan Institute of Massive Amorphous Alloy Science China University of Mining TechnologyXuzhou 221116China Department of Physics King Abdulaziz UniversityJeddah 22254Saudi Arabia MISiS National University of Science and TechnologyMoscow 119049Russia School of Materials Science and engineering Lanzhou Jiaotong UniversityLanzhou 730070China Department of Materials Science and Metallurgy University of CambridgeCambridge CB30FSUK

Multicomponent alloys of Zr_(50)M_(50),Zr_(50)(M,Ag)_(50)and Zr_(50)(M,Pd)_(50)(M=fe,Co,Ni,Cu)can be melt-spun to obtain amorphous *** maximum thickness for fully amorphous ribbons varies with composition in the range 34-53μ*** contrast,fully amorphous ribbons are not obtainable for binary Zr_(50)Ni_(50)or ternary Zr_(50)(Ni,Cu)_(50)***-induced crystallization occurs through:two stages of amorphous[am]→[~(am')+B2]→[B2+B33]for Zr_(50)M_(50);and[am]→[am'+B2]→[B2+AgZr]for Zr_(50)(M,Ag)_(50);and a single stage of[am]→[B2]for Zr_(50)(M,Pd)_(50),while no B2 phase is formed for the binary and ternary Zr_(50)Q_(50)(Q=Ni or/and Cu)***-spun amorphous ribbons have good bending ***,Zr_(50)M_(50)ribbons in tension show 0.22-0.28%plastic elongation and work-hardening(the yield stress is~820 MPa,the fracture stress is~1200 MPa).When cold-rolled at room temperature to 30%reduction in thickness,Zr_(50)M_(50)ribbons show 10%increase in hardness,while retaining good bending ***-rolling induces precipitation of spheroidal B2 and irregular B33 particles,while deformation in tension induces B2,B33 and also plate-like monoclinic *** B2 and B33 particles form by polymorphic transformation,and include a high density of internal *** novel deformationinduced precipitation has not been recognized for any Zr_(50)Q_(50)binary or ternary *** new multicomponent systems are encouraging for future progress as structural amorphous alloys.

关键词： Multicomponent Microstructure Mechanical properties Phase transition Amorphous alloy

Analysis Of Urban Planning Instruments in Comala,Colima,Mexico(1997-2009)from a Gender Perspective-A Secondary Publication

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Journal of Architectural Research and Development 2024年第1期8卷 93-101页

作者： e.J.García espíritu P.Chung Alonso I.BarajasÁvalos M.S.R.Covarrubias Ruesga M.P.Ramírez Rivera National technological Institute of Mexico Mayor Benito Juárez CP 03330Mexico CityMexico

This work is carried out based on the analysis of urban planning instruments,taking the gender perspective as a *** arises from the inclusion of women in the participation of urban development,through an analysis of the gender gaps that have marked the history of women,the inequalities serve as a basis for carrying out this *** highlights the challenges we face today as a society in the process of building citizen participation,where we must all be recognized and have equal opportunities within the territory in which we *** article analyzes the extent to which the Municipal Urban Development Programs of the Mexican municipality of Comala,Colima,Mexico,consider the recommendations on gender and urbanism,established since the 1990s by international entities and applied transversally to urban planning *** differences are found between women and men in terms of empowerment and participation in urban territorial planning instruments,mainly in the oldest instrument(1997).Significant progress is observed in the most recent document and is currently in force in the municipality of Comala(2009).

关键词： Planning instruments Gender perspective Urban planning

Precision bending of high-quality components for volume applications

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Transactions of Nonferrous Metals Society of China 2010年第11期20卷 2100-2110页

作者： T.WeLO F.WIDeRe Department of engineering Design and Materials Norwegian University of Science and Technology(NTNU)

Recent new technology developments were presented in the field of industrial bending operations,including flexible stretch forming and 3D rotary stretch *** were made to give an overview of different mechanisms that influence dimensional accuracy,including local cross-sectional deformations such as suck-in and volume conservation effects,along with global deformations such as *** analytical model was developed to determine the particular influence of different material,geometry and process parameters on dimensional variability of bent *** results were discussed in terms of overall process capability(Cp) and associated process *** results show that different governing mechanisms prevail in various bending operations,meaning that attention has to be placed on controlling those process parameters that really are important to part quality in each specific *** strategies may be defined for reducing *** alternative may be to design more robust process and tool technology that reduce the effect of upstream parameters on dimensional variability of the formed *** results show that optimal tool design and technology may in specific cases improve the dimensional accuracy of a formed *** on the findings discussed herein,it is concluded that advances in industrial bending operations require focus on improving the understanding of mechanical mechanisms,including models and parameter development,new technology developments,including process,tool,measurement and control capabilities,and process discipline at the shop floor,combined with a basic philosophy of controlling process parameters rather than part attributes.

关键词：精密弯曲工艺参数控制应用元件品质尺寸精度拉伸成形回弹变形