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产品显性防伪技术(OACT)投资的供应链决策机制研究
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作者 张子健 何清 《运筹与管理》 CSSCI CSCD 北大核心 2022年第6期67-73,共7页
以OACT防伪体系为研究对象,研究了供应链中品牌厂商及零售商的防伪投资决策机制。建立了产品品牌商与零售商的防伪技术投资决策非合作、决策合作及供应链整合三种决策机制下的博弈模型,得到了三种机制下的均衡防伪可信度、均衡防伪投资... 以OACT防伪体系为研究对象,研究了供应链中品牌厂商及零售商的防伪投资决策机制。建立了产品品牌商与零售商的防伪技术投资决策非合作、决策合作及供应链整合三种决策机制下的博弈模型,得到了三种机制下的均衡防伪可信度、均衡防伪投资阈值以及均衡利润,并进行了比较分析。最后,建立了产品显性防伪技术的供应链防伪投资HSN契约协调机制。研究发现均衡防伪可信度始终随市场假货渗透率的增加而增加,随防伪投资成本系数增加而减少。同时均衡防伪可信度在投资非合作决策机制下最低,在投资合作决策机制下次之,供应链整合情形下最高;均衡防伪投资阈值在非合作决策机制下最低,投资合作情形下次之,供应链整合情形下最高。 展开更多
关键词 显性防伪技术 防伪可信度 供应链决策
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美、德、日、中先进制造技术优势的比较研究 被引量:15
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作者 李林 杨锋林 何建洪 《情报杂志》 CSSCI 北大核心 2020年第10期65-71,58,共8页
[目的/意义]先进制造技术是支撑全球第四次工业革命的重要基石。由于技术策略的差异,先进制造技术在世界各国呈现显著的时间、空间不均衡特征,对其发展特征的探讨将有利于赶超国家抓住发展机会并调整技术创新战略。[方法/过程]基于技术... [目的/意义]先进制造技术是支撑全球第四次工业革命的重要基石。由于技术策略的差异,先进制造技术在世界各国呈现显著的时间、空间不均衡特征,对其发展特征的探讨将有利于赶超国家抓住发展机会并调整技术创新战略。[方法/过程]基于技术生命周期理论,运用Logistic模型与RTA指数对美、德、日、中在先进制造技术创新的时间序列、子领域空间分布情况进行分析,进而简要比较了不同国家的先进制造技术优势以及对中国发展先进制造技术可能启示。[结果/结论]结果发现,无论是从整体的时间序列,还是特定的国家看,先进制造技术子领域创新发展并不均衡,这种不均衡可能是各国政府直接或间接干预的结果;从技术生命周期趋势看,2017-2023年是全球先进制造技术转型发展的一个重要时期,多数技术领域都存在创新突破的机会窗口,因此也可能是后发国家实现追赶的时间窗口。有效识别这样的机会窗口对于我国制定引导性政策推动先进制造技术创新、加快经济转型发展有着重要的意义。 展开更多
关键词 先进制造技术 技术生命周期 显性技术优势指数 技术领先 专利 工业强国
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产业政策推动了技术创新吗?——基于我国移动通信技术发展的分析 被引量:2
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作者 何建洪 赵慧祺 +2 位作者 崔雨晴 王淞立 李雨桐 《创新科技》 2020年第12期1-14,共14页
以我国移动通信技术创新为对象,应用K-Means和层次聚类对产业政策进行文本分析,并应用显性技术优势指数(RTA)和变异系数(CV)刻画技术创新效果,剖析了我国移动通信技术中产业政策与自主创新成果间的联系与作用机理。结果表明,在特定技术... 以我国移动通信技术创新为对象,应用K-Means和层次聚类对产业政策进行文本分析,并应用显性技术优势指数(RTA)和变异系数(CV)刻画技术创新效果,剖析了我国移动通信技术中产业政策与自主创新成果间的联系与作用机理。结果表明,在特定技术领域及技术演化的不同阶段,不同类别的政策及其组合驱动技术创新的效果存在显著差异,其中,在技术演化轨迹确定、资金等生产要素充分的情境下,政策的排他性保护、反垄断干预与引资性培育促进通信技术创新效果最为显著;而税收优惠的创新驱动效果不显著,通过政府补贴刺激创新甚至可能出现抑制效应。本文的研究表明,产业政策在特定领域中对技术创新的刺激是有效的,同时表明即使在特定领域中,产业政策在技术发展的不同阶段其作用效果也存在显著差异。这对我国在制造业关键核心技术和通用共性技术等特定领域制定实施激励性产业政策、有效参与全球前沿技术竞争具有重要的启示意义。 展开更多
关键词 产业政策 显性技术优势指数(RTA) 移动通信技术 创新 聚类分析
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中国区域技术布局是稳定的吗?
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作者 冯仁涛 《北京化工大学学报(社会科学版)》 2017年第4期7-16,共10页
了解技术能力在区域空间的布局情况,对区域和国家的技术和产业战略,尤其是战略性新兴产业发展政策的制定有重要意义。利用中国各省区在1985-2012年间的国内发明专利授权数据,将专利数据的分类信息与技术领域对应,构造了表示区域技术专... 了解技术能力在区域空间的布局情况,对区域和国家的技术和产业战略,尤其是战略性新兴产业发展政策的制定有重要意义。利用中国各省区在1985-2012年间的国内发明专利授权数据,将专利数据的分类信息与技术领域对应,构造了表示区域技术专业化模式的显性技术优势指标(RTA)。通过Galtonian回归分析发现中国27个省区,除天津外,技术布局都有较强的稳定性,北京技术布局的稳定性最强,所有省区技术布局的稳定性都随时间间隔的延长而减弱。同时,除北京外的省区技术专业化程度呈现先上升后下降的变化,表明技术能力在技术领域的布局存在先收敛后分散的规律。 展开更多
关键词 技术布局 发明专利 显性技术优势 技术专业化 区域创新
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技术知识与产品创新的辩证互动 被引量:1
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作者 卢艳 《科技与管理》 2006年第3期130-132,共3页
企业作为经济社会的主体,肩负着推动经济增长、社会进步的重大使命。通过对企业产品创新全过程的分析,得出了技术知识和产品创新的双向互动关系。
关键词 产品创新 显性技术知识 隐性技术知识 技术知识 企业
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遗传不育技术在蚊媒疾病防控中的应用 被引量:2
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作者 王玉生 李建伟 +3 位作者 张桂芬 严盈 李昕玥 万方浩 《生物安全学报》 2015年第2期148-160,共13页
疟疾、登革热等重大传染性蚊媒疾病严重危害人类健康,且目前缺乏有效的药物和疫苗,防治埃及伊蚊、冈比亚按蚊等媒介昆虫是控制和消除这些疾病的有效手段。化学杀虫剂的大规模使用在一定程度上控制了疾病的传播,但其抗药性和环境污染等... 疟疾、登革热等重大传染性蚊媒疾病严重危害人类健康,且目前缺乏有效的药物和疫苗,防治埃及伊蚊、冈比亚按蚊等媒介昆虫是控制和消除这些疾病的有效手段。化学杀虫剂的大规模使用在一定程度上控制了疾病的传播,但其抗药性和环境污染等问题也随之而来。分子生物学的飞速发展为昆虫不育技术(SIT)的更新及害虫防治提供了新的策略,由此发展起来的以释放携带显性致死基因昆虫(RIDL)为代表的一系列遗传不育技术为蚊虫种群防控提供了更加有效的选择。本文概述了遗传技术在蚊虫防控中的应用进展,包括蚊虫遗传防治的历史和策略,阐述了RIDL技术体系的原理,同时介绍了相关遗传控制品系和已经开展的田间释放研究,展示了遗传修饰不育技术在蚊媒疾病防治中的巨大潜力。 展开更多
关键词 蚊媒昆虫 遗传防治 昆虫不育技术 释放携带显性致死基因昆虫的技术
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传统环境营造技艺的生态智慧研究 被引量:6
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作者 华亦雄 周浩明 《生态经济》 CSSCI 北大核心 2016年第1期218-220,共3页
传统环境营造技艺是古人在不断适应自然环境的过程中逐渐成熟的建筑与景观营造技艺,其所蕴含的生态智慧包括对自然材料的巧妙运用、高度适应性的结构设计以及节能节材的工艺体系。通过对传统环境营造技艺的生态智慧研究,来探寻其在当代... 传统环境营造技艺是古人在不断适应自然环境的过程中逐渐成熟的建筑与景观营造技艺,其所蕴含的生态智慧包括对自然材料的巧妙运用、高度适应性的结构设计以及节能节材的工艺体系。通过对传统环境营造技艺的生态智慧研究,来探寻其在当代设计产业中应用与推广的正确方向。 展开更多
关键词 传统环境营造技艺 隐性技术 显性技术 工艺体系
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海外跨国公司在华人工智能专利布局及竞争态势研究 被引量:3
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作者 寇园园 陈会英 +1 位作者 徐华杰 刘凯 《情报杂志》 CSSCI 北大核心 2022年第9期48-54,共7页
[研究目的]中国已成为海外跨国公司人工智能专利布局的重要目标市场,探究海外跨国公司在华人工智能专利布局及竞争态势,有助于防止其在华进行垄断式专利布局,为中国企业和政府机构在长期性科技竞争中制定和调整专利战略提供理论依据。[... [研究目的]中国已成为海外跨国公司人工智能专利布局的重要目标市场,探究海外跨国公司在华人工智能专利布局及竞争态势,有助于防止其在华进行垄断式专利布局,为中国企业和政府机构在长期性科技竞争中制定和调整专利战略提供理论依据。[研究方法]从IPC专利分类视角出发,利用马尔可夫链和显性技术比较优势指数,识别海外跨国公司在华人工智能专利布局的演进特征和演变结果,运用结构相似度和结构调整度指数,衡量中国市场人工智能专利竞争态势。[研究结论]海外跨国公司采取了积极扩张的专利策略,不断扩大人工智能专利布局范围;布局重心由基础算法向基础硬件和垂直应用领域转移,形成了25个新兴领域和17个重点领域,部分领域持续发展成为较稳定的优势领域;中国同美国、日本、韩国和欧洲的人工智能跨国公司技术互补性降低、竞争程度增加,特别是与美国跨国公司的技术竞争最为激烈。 展开更多
关键词 人工智能 专利布局 专利分类 专利竞争态势 海外跨国公司 马尔可夫链 显性技术比较优势指数 结构相似度和结构调整度指数
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Laser Capture Microdissection Combined with RNA in vitro Linear Amplification Detecting the Relevant Genes of Bladder Cancer
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作者 郝权 徐勇 +2 位作者 李文录 赵小鸽 刘文欣 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第5期309-313,327,共6页
Objective: Laser capture microdisection has become indispensable to the analysis of the difference of gene expression between human bladder transitional cell and bladder transitional cell carcinoma (BTCC). However,... Objective: Laser capture microdisection has become indispensable to the analysis of the difference of gene expression between human bladder transitional cell and bladder transitional cell carcinoma (BTCC). However, to obtain sufficient RNA from laser-capture microdissected cells is quite difficult. The study was designed to determinc a feasible technical routine to isolate transitional cells from bladder membrane, separate carcinoma cclls from stromal cells and to amplify the RNA isolated from laser-capture microdissected cells. Methods: Bladder transitional cell were obtained from frozen sections of bladder membrane applying LCM, by the same token, BTCC cells from frozen sections of BTCC tissue. Then RNA was extracted and linearly amplified in vitro. The expression levels of β-actin in primary total RNA and amplified RNA were detected using RT-PCR. Results: That RNA integrity was good after LCM was confirmed by control experiment Ⅰ; By control experiment Ⅱ, the correlation between the number of LCM-shooting and RNA quantity undcr arranged conditions was preliminarily confirmed. About 0.5-2.5kb RNA fragments were obtained after RNA amplification and β-actin levels were integral. Conclusion: Laser capture microdissection combined with RNA linear amplification in vitro can be successfully applied to obtain pure objective cells for research. The integrity of the amplified RNA is good and can be employed in further research. 展开更多
关键词 aser capture microdissection RNA linear amplification in vitro RT-PCR bladder transitionalcell bladder transitional cell carcinoma
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False Positives Caused by Single Primer in DDRT Analysis of Soybean
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作者 魏益凡 魏先运 《Agricultural Science & Technology》 CAS 2011年第2期222-223,236,共3页
[Objective] The aim was to explore the reasons of false positives in Different Display Reverse Transcription(DDRT)analysis.[Method] Soybean varieties "Jilin 30" and "Tongnong 13" were used as materials to carry ... [Objective] The aim was to explore the reasons of false positives in Different Display Reverse Transcription(DDRT)analysis.[Method] Soybean varieties "Jilin 30" and "Tongnong 13" were used as materials to carry out analysis on false positives in DDRT analysis.[Result] An important origin of false positives appeared in DDRT analysis was the non-specific amplification caused by the combination of single primer and cDNA.The parallel PCR test of single primer should be set so as to verify whether the obtained fragments were the false positives or the PCR productions combined with single primer.[Conclusion] This study had provided basis for improving the success rate of DDRT experiment. 展开更多
关键词 Different Display Reverse Transcription(DDRT) Single primer PCR False positive Application
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冈比亚按蚊性别决定基因doublesex的克隆、序列分析及表达谱 被引量:3
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作者 刘培文 李小聪 +2 位作者 顾金保 刘艳 陈晓光 《昆虫学报》 CAS CSCD 北大核心 2015年第2期122-131,共10页
【目的】doublesex是控制昆虫性别分化的关键基因,决定了昆虫体细胞与生殖细胞的性别。本研究旨在克隆、鉴定重要疟疾媒介冈比亚按蚊Anopheles gambiae性别决定基因doublesex(Angdsx),分析其在雌雄个体内的剪切体及在不同发育时期的表... 【目的】doublesex是控制昆虫性别分化的关键基因,决定了昆虫体细胞与生殖细胞的性别。本研究旨在克隆、鉴定重要疟疾媒介冈比亚按蚊Anopheles gambiae性别决定基因doublesex(Angdsx),分析其在雌雄个体内的剪切体及在不同发育时期的表达模式。【方法】基于冈比亚按蚊转录组数据库,比对到Angdsx相关片段,分别以雌雄成蚊c DNA为模板,采用RT-PCR与RACE方法克隆分别获得雌雄个体内Angdsx全长基因,利用生物信息软件对所得序列进行结构域预测、氨基酸序列比对和进化树分析。根据Angdsx特异性表达引物,利用RT-PCR方法研究其在冈比亚按蚊雌雄个体及不同发育时期的表达谱。【结果】分别从冈比亚按蚊雌雄成虫中克隆获得Angdsx c DNA全长序列,分别命名为AngdsxF(Gen Bank登录号:KM978937)和AngdsxM(Gen Bank登录号:KM978938)。Angdsx位于2号常染色体右臂,基因横跨接近80 kb基因组长度。AngdsxF长度为4 874 nt,编码长度为265个氨基酸的雌性特异性蛋白DSXF;AngdsxM长度为3 183 nt,编码长度为633个氨基酸的雄性特异性蛋白DSXM。结构域分析发现Angdsx包括doublesex保守的TRA/TRA-2结合位点、dsx重复序列、富含精氨酸/丝氨酸双肽区、多聚嘌呤增强子序列和RNA结合蛋白结合序列,以及连续的双核苷酸GT为主的重复序列。与AngdsxF相比,AngdsxM具有一个雌性特异性的外显子。AngdsxM在0-2 h卵中高表达,随后逐渐减少,在12-24 h卵中降至最低,之后再次升高;AngdsxF则在6-8 h卵中开始表达。【结论】本研究获得了冈比亚按蚊性别决定基因Angdsx在雌雄个体内的全长序列,Angdsx具有保守的结构域与表达特征。本研究结果为蚊虫性别分化的分子机制及将其最终应用于显性致死昆虫施放技术进行蚊媒的防制提供了理论基础。 展开更多
关键词 冈比亚按蚊 性别决定基因 DOUBLESEX 显性致死昆虫施放技术 序列分析 表达谱
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Review of recent trends in friction stir welding process of aluminum alloys and aluminum metal matrix composites 被引量:16
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作者 John VICTOR CHRISTY Abdel-Hamid ISMAIL MOURAD +1 位作者 Muhammad M.SHERIF B.SHIVAMURTHY 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第11期3281-3309,共29页
Welding is a vital component of several industries such as automotive,aerospace,robotics,and construction.Without welding,these industries utilize aluminum alloys for the manufacturing of many components or systems.Ho... Welding is a vital component of several industries such as automotive,aerospace,robotics,and construction.Without welding,these industries utilize aluminum alloys for the manufacturing of many components or systems.However,fusion welding of aluminum alloys is challenging due to several factors,including the presence of non-heat-treatable alloys,porosity,solidification,and liquation of cracks.Many manufacturers adopt conventional in-air friction stir welding(FSW)to weld metallic alloys and dissimilar materials.Many researchers reported the drawbacks of this traditional in-air FSW technique in welding metallic and polymeric materials in general and aluminum alloys and aluminum matrix composites in specific.A number of FSW techniques were developed recently,such as underwater friction stir welding(UFSW),vibrational friction-stir welding(VFSW),and others,for welding of aluminum alloy joints to overcome the issues of welding using conventional FSW.Therefore,the main objective of this review is to summarize the recent trends in FSW process of aluminum alloys and aluminum metal matrix composites(Al MMCs).Also,it discusses the effect of welding parameters of the traditional and state-of-the-art developed FSW techniques on the welding quality and strength of aluminum alloys and Al MMCs.Comparison among the techniques and advantages and limitations of each are considered.The review suggests that VFSW is a viable option for welding aluminum joints due to its energy efficiency,economic cost,and versatile modifications that can be employed based on the application.This review also illustrated that significantly less attention has been paid to FSW of Al-MMCs and considerable attention is demanded to produce qualified joint. 展开更多
关键词 aluminum alloys aluminum matrix composites traditional FSW techniques state-of-the-art FSW techniques microstructure mechanical properties
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Dispersion and STM Characterization of Au-CdSe Nanohybrids on Au(111) 被引量:1
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作者 Bo Gao Yan-min Kuang +1 位作者 Yuan Liao Zhen-chao Dong 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第2期231-234,I0004,共5页
We report the dispersion and scanning tunneling microscopy (STM) characterization of iso- lated Au-CdSe nanohybrids on atomically fiat Au(111) through surface modifications. The top terminal groups of spacer molec... We report the dispersion and scanning tunneling microscopy (STM) characterization of iso- lated Au-CdSe nanohybrids on atomically fiat Au(111) through surface modifications. The top terminal groups of spacer molecules self-assembled on the surface are found critical for locking the nanohybrids into a well-separated state. The STM results indicate that both thiol and carboxylic terminals are effective in this aspect by making strong interaction with the Au portions of the nanohybrids. An argon ion sputtering technique is also proposed to clean up organic contaminants on the surface for improved STM imaging of individual Au-CdSe nanohybrids. These observations help to enrich technical approaches to dispersing individual nanostructures on the surface and provide opportunities to explore their local electroluminescent and energy transfer properties at the nanoscale. 展开更多
关键词 Metal-semiconductor nanostructure Nanoparticle dispersion Sputter cleaning Scanning tunneling microscopy Plasmon-exciton coupling
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Tumor Molecular Imaging with Nanoparticles 被引量:3
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作者 Zhen Cheng Xuefeng Ya +2 位作者 Xilin Sun BaozhongShen Sanjiv Sam Gambhir 《Engineering》 SCIE EI 2016年第1期132-140,共9页
Molecular imaging(MI)can provide not only structural images using traditional imaging techniques but also functional and molecular information using many newly emerging imaging techniques.Over the past decade,the util... Molecular imaging(MI)can provide not only structural images using traditional imaging techniques but also functional and molecular information using many newly emerging imaging techniques.Over the past decade,the utilization of nanotechnology in MI has exhibited many significant advantages and provided new opportunities for the imaging of living subjects.It is expected that multimodality nanoparticles(NPs)can lead to precise assessment of tumor biology and the tumor microenvironment.This review addresses topics related to engineered NPs and summarizes the recent applications of these nanoconstructs in cancer optical imaging,ultrasound,photoacoustic imaging,magnetic resonance imaging(MRI),and radionuclide imaging.Key challenges involved in the translation of NPs to the clinic are discussed. 展开更多
关键词 TUMOR Molecular imaging NANOPARTICLES
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Mechanical properties of 3D carbon/carbon composites by nanoindentation technique 被引量:5
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作者 WEI Li-ming ZHANG Yue +2 位作者 XU Cheng-hai QI Fei MENG Song-he 《Journal of Central South University》 SCIE EI CAS 2012年第1期36-40,共5页
Nanoindentation tests were conducted to investigate the near-surface mechanical properties of the individual components(fiber and matrix) for three-dimensional reinforced carbon/carbon composites(3D C/C).Optical micro... Nanoindentation tests were conducted to investigate the near-surface mechanical properties of the individual components(fiber and matrix) for three-dimensional reinforced carbon/carbon composites(3D C/C).Optical microscope and polarizing light microscope were used to characterize the microstructure of 3D C/C.The microscopy results show that large number of pores and cracks exist at both bundle/matrix interface and pitch carbon matrix.These defects have important effect on the mechanical behavior of 3D C/C.The in situ properties for components of 3D C/C were acquired by nanoindentation technique.Relative to the matrix sample,the fiber samples have more larger values for modulus,stiffness and hardness.However,there is no significant difference of modulus and stiffness among fiber samples with different directions. 展开更多
关键词 C/C composites mechanical properties NANOINDENTATION MICROSTRUCTURE
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我国区域技术专业化模式比较研究 被引量:8
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作者 冯仁涛 余翔 《科研管理》 CSSCI 北大核心 2012年第10期9-16,共8页
区域技术专业化模式反映了区域技术能力的分布情况,了解技术能力的分布是制定科学合理的区域技术发展战略的前提和基础。本文利用我国31个省区在1985-2010年间的国内发明专利授权数据,将专利数据的国际分类信息与技术领域对应,构造表示... 区域技术专业化模式反映了区域技术能力的分布情况,了解技术能力的分布是制定科学合理的区域技术发展战略的前提和基础。本文利用我国31个省区在1985-2010年间的国内发明专利授权数据,将专利数据的国际分类信息与技术领域对应,构造表示区域技术专业化模式的显性技术优势指标(RTA),分析了各省区跨技术领域专业化模式及其随时间的变化情况,并对各省区的技术专业化模式进行了评价,为有针对性的制定技术发展战略提供参考。 展开更多
关键词 技术专业化 发明专利 显性技术优势 区域技术优势
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Optimization of tribological parameters over WC-12%Co laser alloyedpearlitic ductile iron using Taguchi based Grey relational analysis
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作者 N.JEYAPRAKASH YANG Che-hua TSENG Sheng-po 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第3期736-751,共16页
Pearlitic ductile irons(PDIs)are used in transportation and nuclear energy industries.In heavy loading situation,the service life of PDI is affected by numerous tribo aspects.In this study,surface of the PDI is alloye... Pearlitic ductile irons(PDIs)are used in transportation and nuclear energy industries.In heavy loading situation,the service life of PDI is affected by numerous tribo aspects.In this study,surface of the PDI is alloyed with WC-12%Co powder using a high power fibre laser.The wear properties of the base material and laser alloying samples were investigated by tribometer with various parameters,i.e.,temperature,load and sliding speed.Based on experimental test,the load has maximum percentage of contribution and followed by sliding speed and working temperature.The optimized tribological parameters by Grey relational analysis(GRA)were established and those values are closely matched with predicted values.Besides,base material and laser alloying surfaces were examined through Vickers hardness machine,scanning electron microscopy(SEM)and roughness tester.The laser altered specimen shows no defects and improves the wear properties than substrates.The identified optimal tribological parameters are load of 30 N,speed of 0.5 m/s and working temperature of 300℃,and load of 30 N,speed of 0.5 m/s and working temperature of 200℃ for base metal and laser alloying samples,respectively. 展开更多
关键词 WC-12%Co laser alloying microstructure wear resistance Grey technique analysis of variance OPTIMIZATION roughness
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Calcium phosphate deposition on surface of porous and dense TiNi alloys in simulated body fluid
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作者 刘珏 刘超 +2 位作者 李婧 刘敏 阮建明 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第1期1-9,共9页
Porous and dense TiNi alloys were successfully fabricated by powder metallurgy(P/M) method, and to further improve their surface biocompatibility, surface modification techniques including grind using silicon-carbide(... Porous and dense TiNi alloys were successfully fabricated by powder metallurgy(P/M) method, and to further improve their surface biocompatibility, surface modification techniques including grind using silicon-carbide(SiC) paper, acid etching and alkali treatment were employed to produce either irregularly rough surface or micro-porous surface roughness. X-ray diffractometry(XRD), scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDX) attached to SEM were used to characterize surface structure and the Ca-P coatings. Effects of the above surface treatments on the surface morphology, apatite forming ability were systematically investigated. Results indicate that all the above surface treatments increase the apatite forming ability of TiNi alloys in varying degrees when soaked in simulated body fluid(SBF). More apatite coatings formed on TiNi samples sintered at 1050℃ and 1100℃ due to their high porosity and pure TiNi phase that is beneficial to heterogeneous nucleation. Furthermore, more uniform apatite was fabricated on the sample sintered from the mixture of Ni and Ti powders. 展开更多
关键词 calcium phosphate TiNi alloy surface treatment MICROSTRUCTURE simulated body fluid (SBF)
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Effect of Additives on the Performance of Lead Acid Batteries
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作者 Lankipalli Rekha Manne Venkateswarlu Kurivella Suryanarayana Murthy Mandava Jagadish 《Journal of Energy and Power Engineering》 2015年第10期866-871,共6页
Effect of titanium dioxide (TiO2) and carbon additives in the respective positive and negative material properties and the influence on the performance of the battery were investigated. The electrode samples were ch... Effect of titanium dioxide (TiO2) and carbon additives in the respective positive and negative material properties and the influence on the performance of the battery were investigated. The electrode samples were characterized by BET (Brunauer Emmett Teller), XRD (X-ray diffractometer), SEM (scanning electron microscopy) and EIS (electrochemical impedance spectroscopy) to understand the surface area, phase, structure, morphology and electrical conductivity of the respective electrode material. The surface area was obtained as 2.312 m2"g"l and 0.892 m2"g"1, respectively for 12% of activated carbon in the expander of negative and 0.70% of TiO2 (Titanium dioxide) in the PAM (positive active material). The structural analysis reveals an increase in the tetrabasic lead sulfate and also evidenced by well grown crystals in the PAM with the TiO2, respectively obtained by XRD and SEM techniques. The impedance spectra analysis shows an increase of electrical conductivity of negative active mass with temperature. The battery results showing two fold enhancements in the charge acceptance were attributed to the high surface area activated carbon in the NAM (negative active material). The materials properties of electrodes and their influence on the battery performance were discussed. 展开更多
关键词 Titanium dioxide CARBONS charge acceptance lead acid battery.
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“技术增加值”评价原理与方法 被引量:11
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作者 巨建国 汤万金 《数学的实践与认识》 CSCD 北大核心 2009年第6期147-153,共7页
提出了"技术增加值"的概念,认为公司价值不仅包括"经济增加值",还应包括"技术增加值".在系统地比较了"经济增加值"与"技术增加值"两个概念和形成过程的基础上,给出了技术增加值的评... 提出了"技术增加值"的概念,认为公司价值不仅包括"经济增加值",还应包括"技术增加值".在系统地比较了"经济增加值"与"技术增加值"两个概念和形成过程的基础上,给出了技术增加值的评价模型、评价方法和评价步骤,最后通过两个应用示例予以说明.提出应用"技术增加值"指标,更加客观反映企业的全面价值和业绩. 展开更多
关键词 技术增加值 经济增加值 技术隐性收益 技术显性收益 技术就绪指数 技术就绪水平
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