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Universal design of three-dimensional porous graphene-iron based promotors for kinetically rationalized lithium-sulfur chemistry
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作者 Hua Gao Yunfeng Zhang +6 位作者 Menglei Wang Ruoxuan Yang Shuai Feng Xuan Cao Yaping Zhang Zhongyuan Lu Yingze Song 《Journal of Energy Chemistry》 2025年第1期192-200,共9页
Lithium-sulfur(Li-S)batteries are widely deemed to be one of the most potential candidates for future secondary batteries because of their remarkable energy density.Nevertheless,notorious polysulfide shuttling and ret... Lithium-sulfur(Li-S)batteries are widely deemed to be one of the most potential candidates for future secondary batteries because of their remarkable energy density.Nevertheless,notorious polysulfide shuttling and retarded sulfur reaction kinetics pose significant obstacles to the further application of Li-S batteries.While rationally designed highly active electrocatalysts can facilitate polysulfide conversion,the universal and scalable synthesis strategies need to be developed.Herein,a universal synthetic strategy to construct a series of three-dimensional(3D)porous graphene-iron(3DGr-Fe)based electrocatalysts involving 3DGr-FeP,3DGr-Fe_(3)C,and 3DGr-Fe_(3)Se_(4)is exploited for manipulating the Li-S redox reactions.It has been observed that the implementation of a 3D porous Gr architecture leads to the well-designed conductive networks,while the uniformly dispersed iron nanoparticles introduce an abundance of active sites,fostering the lithium polysulfide conversion,thereby bolstering the overall electrochemical performance.The Li-S battery with the 3DGr-Fe based electrocatalyst exhibits remarkable capacity retention of 94.8%upon 100 times at 0.2 C.Moreover,the soft-packaged Li-S pouch cell based on such a 3DGr-Fe electrocatalyst delivers superior capacity of 1060.71 mA h g^(-1)and guarantees for the continuous 30 min work of fan toy.This investigation gives comprehensive insights into the design,synthesis,and mechanism of 3DGr-Fe based electrocatalysts with high activity toward efficient and durable Li-S batteries. 展开更多
关键词 Lithium-sulfur battery Universal synthesis 3d graphene-iron based promotor ELECTrOCATALYSIS
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供应链金融对中小企业R&D投资效率的影响:基于融资约束视角 被引量:1
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作者 胡海青 原敏倩 薛萌 《科技进步与对策》 北大核心 2025年第1期102-112,共11页
创新是中小企业保持竞争力、适应市场变化和实现可持续发展的关键。基于2016-2022年创业板中小企业相关数据,运用三阶段DEA分析、面板Tobit模型回归、二元Logistic回归等方法,探究供应链金融对中小企业R&D投资效率的影响。结果表明... 创新是中小企业保持竞争力、适应市场变化和实现可持续发展的关键。基于2016-2022年创业板中小企业相关数据,运用三阶段DEA分析、面板Tobit模型回归、二元Logistic回归等方法,探究供应链金融对中小企业R&D投资效率的影响。结果表明,供应链金融能够显著提高中小企业R&D投资效率,融资约束在二者间发挥遮掩效应。进一步分析发现,上述效应对供应链集中度较高的企业更为显著。结论可为发挥供应链金融筹资优势,促进供应链生态系统资源互补、信息共享的协同创新网络形成,进而支持中小企业创新活动提供理论支持。 展开更多
关键词 供应链金融 r&d投资效率 三阶段dEA 面板Tobit模型 遮掩效应
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非洲猪瘟病毒D205R蛋白单克隆抗体的制备和抗原表位鉴定
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作者 林志钊 赵燕燕 +6 位作者 任豪杰 史赛燕 韩世充 何文瑞 万博 张雨杭 张改平 《河南农业科学》 北大核心 2025年第2期124-130,共7页
非洲猪瘟(ASF)是一种致命的传染病,迄今为止,还没有开发出有效的疫苗或药物用于预防或控制ASF。为提供诊断非洲猪瘟病毒(ASFV)的重要材料,利用大肠杆菌系统表达ASFV重组D205R蛋白,制备D205R蛋白的单克隆抗体(mAb),鉴定mAb识别的抗原表... 非洲猪瘟(ASF)是一种致命的传染病,迄今为止,还没有开发出有效的疫苗或药物用于预防或控制ASF。为提供诊断非洲猪瘟病毒(ASFV)的重要材料,利用大肠杆菌系统表达ASFV重组D205R蛋白,制备D205R蛋白的单克隆抗体(mAb),鉴定mAb识别的抗原表位。结果显示,成功构建pET32a-D205R表达质粒,并纯化大小约为44 ku的重组D205R蛋白。蛋白质免疫印迹(Western blot)检测结果表明,重组D205R蛋白与ASFV阳性血清发生特异性反应,有良好的免疫原性。利用杂交瘤细胞融合、筛选的方法,得到mAb 19A5。Western blot和间接免疫荧光试验(IFA)检测结果表明,mAb 19A5能特异性识别真核表达的重组D205R蛋白,并能检测到野生型D205R蛋白。用丙氨酸扫描法鉴定出167-SDPPVVWLGGRPGD-180是mAb 19A5的抗原表位,S167、W173、L174、G175、P178和D180是与mAb19A5结合的关键氨基酸。保守性和结构分析表明,抗原表位高度保守,且位于蛋白质表面,是线性表位。综上,成功制备mAb 19A5,并鉴定了mAb 19A5识别的抗原表位。 展开更多
关键词 非洲猪瘟病毒 d205r蛋白 单克隆抗体 抗原表位
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绿色金融、R&D投入与碳排放的内在关联性研究——基于省际面板数据的实证检验
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作者 刘伟 纪明 +1 位作者 韩进 王竞一 《工业技术经济》 北大核心 2025年第3期45-55,共11页
“碳达峰”和“碳中和”目标下,如何推动中国碳减排与经济绿色低碳转型,已经成为中国高质量发展的重要议题。本文基于2010~2022年我国30个省(区、市)的面板数据,探析了绿色金融和科技研发对碳排放的影响,实证证明了绿色金融与R&D投... “碳达峰”和“碳中和”目标下,如何推动中国碳减排与经济绿色低碳转型,已经成为中国高质量发展的重要议题。本文基于2010~2022年我国30个省(区、市)的面板数据,探析了绿色金融和科技研发对碳排放的影响,实证证明了绿色金融与R&D投入均对碳排放起到显著的抑制作用,而且R&D投入在绿色金融与碳排放之间的起到显著的负向调节作用,它既是绿色金融政策落地的关键驱动力,也是减少碳排放的重要技术手段。因此,我国应当加强绿色金融政策支持、发挥R&D投入和技术创新在实现碳减排中的关键驱动作用,同时推动绿色金融与科技研发协同发展。 展开更多
关键词 绿色金融 科技创新 r&d投入 碳排放 熵权法 单位根检验 区域异质性 科技研发
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A novel spin-FET based on 2D antiferromagnet 被引量:2
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作者 Jianlu Wang 《Journal of Semiconductors》 EI CAS CSCD 2019年第2期11-12,共2页
Engineering the electronic band structure of material systems enables the unprecedented exploration of new physical properties that are absent in natural or as-synthetic materials.Electronic structures of bilayer two-... Engineering the electronic band structure of material systems enables the unprecedented exploration of new physical properties that are absent in natural or as-synthetic materials.Electronic structures of bilayer two-dimensional(2D)systems can be flexibly engineered by the external electric field.For example. 展开更多
关键词 In FET A NOVEL spin-FET based on 2d ANTIFErrOMAGNET
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Uncertainty Theory Based Novel Multi-Objective Optimization Technique Using Embedding Theorem with Application to R &D Project Portfolio Selection 被引量:2
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作者 Rupak Bhattacharyya Amitava Chatterjee Samarjit Kar 《Applied Mathematics》 2010年第3期189-199,共11页
This paper introduces a novice solution methodology for multi-objective optimization problems having the coefficients in the form of uncertain variables. The embedding theorem, which establishes that the set of uncert... This paper introduces a novice solution methodology for multi-objective optimization problems having the coefficients in the form of uncertain variables. The embedding theorem, which establishes that the set of uncertain variables can be embedded into the Banach space C[0, 1] × C[0, 1] isometrically and isomorphically, is developed. Based on this embedding theorem, each objective with uncertain coefficients can be transformed into two objectives with crisp coefficients. The solution of the original m-objectives optimization problem with uncertain coefficients will be obtained by solving the corresponding 2 m-objectives crisp optimization problem. The R & D project portfolio decision deals with future events and opportunities, much of the information required to make portfolio decisions is uncertain. Here parameters like outcome, risk, and cost are considered as uncertain variables and an uncertain bi-objective optimization problem with some useful constraints is developed. The corresponding crisp tetra-objective optimization model is then developed by embedding theorem. The feasibility and effectiveness of the proposed method is verified by a real case study with the consideration that the uncertain variables are triangular in nature. 展开更多
关键词 Uncertainty Theory UNCErTAIN Variable EMBEddING THEOrEM α-Optimistic and α-Pessimistic Value r & d Project POrTFOLIO Selection
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Design and R&D Progress of China Lead-Based Reactor for ADS Research Facility 被引量:29
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作者 Yican Wu 《Engineering》 SCIE EI 2016年第1期124-131,共8页
In 2011,the Chinese Academy of Sciences launched an engineering project to develop an acceleratordriven subcritical system(ADS)for nuclear waste transmutation.The China Lead-based Reactor(CLEAR),proposed by the Instit... In 2011,the Chinese Academy of Sciences launched an engineering project to develop an acceleratordriven subcritical system(ADS)for nuclear waste transmutation.The China Lead-based Reactor(CLEAR),proposed by the Institute of Nuclear Energy Safety Technology,was selected as the reference reactor for ADS development,as well as for the technology development of the Generation IV lead-cooled fast reactor.The conceptual design of CLEAR-I with 10 MW thermal power has been completed.KYLIN series lead-bismuth eutectic experimental loops have been constructed to investigate the technologies of the coolant,key components,structural materials,fuel assembly,operation,and control.In order to validate and test the key components and integrated operating technology of the lead-based reactor,the lead alloy-cooled non-nuclear reactor CLEAR-S,the lead-based zero-power nuclear reactor CLEAR-0,and the lead-based virtual reactor CLEAR-V are under realization. 展开更多
关键词 Accelerator-driven subcritical system (AdS) China Lead-based reactor (CLEAr Lead-bismuth eutectic (LBE)Technology rd
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Design of Cylindrical Cam with Oscillating Follower Based on 3D Expansion of Planar Profile Model 被引量:2
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作者 CHEN Junhua LIN Zuan WU Yijie 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期665-670,共6页
Cylindrical cam with oscillating follower is widely applicable and used in many mechanical devices and machines. However, a common error exists in the methods of designing planar profile for oscillating follower cylin... Cylindrical cam with oscillating follower is widely applicable and used in many mechanical devices and machines. However, a common error exists in the methods of designing planar profile for oscillating follower cylinder cam. In this study, we propose a new hypothesis to solve this design problem with the inclusion of deviation angle. On the basis of this new concept, equations for planar profile expansion and methods of calculating pressure angle are deduced by applying 3D expansion formula of the follower's motion orbit. When the pressure angle is less than allowable value, the minimum base radius can be determined by using MATLAB software. Accordingly, the planar profile of oscillating follower cylinder cam is generated by CAD software. This new method is practical and can be easily adopted for the design of oscillating follower cylindrical cam with desirable accuracy. We applied the method in the design of cylindrical cam for paper feeding mechanism used in high-speed printers. We calculated the planar profile and used it to direct the NC machine for the manufacture of the groove of cylindrical cam. The improved cylindrical cam met all of the requirements of speed and accuracy demanded by high-speed printers. Therefore, our new method has been validated by practical application. 展开更多
关键词 oscillating follower cylindrical cam 3d expansion pressure angle radius of base circle PrOFILE
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Expert recommendation system based on analyzing expertise and networks of human resources in National Science & Technology Information Service 被引量:2
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作者 YANG Myung-seok KANG Nam-kyu +3 位作者 KIM Yun-jeong KIM Jae-soo CHOI Kwang-nam KIM Young-kuk 《Journal of Central South University》 SCIE EI CAS 2013年第8期2212-2218,共7页
This work aims to implement expert and collaborative group recommendation services through an analysis of expertise and network relations NTIS. First of all, expertise database has been constructed by extracting keywo... This work aims to implement expert and collaborative group recommendation services through an analysis of expertise and network relations NTIS. First of all, expertise database has been constructed by extracting keywords after indexing national R&D information in Korea (human resources, project and outcome) and applying expertise calculation algorithm. In consideration of the characteristics of national R&D information, weight values have been selected. Then, expertise points were calculated by applying weighted values. In addition, joint research and collaborative relations were implemented in a knowledge map format through network analysis using national R&D information. 展开更多
关键词 human networks network analysis NTIS rd information
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6R Robot Inverse Solution Algorithm Based on Quaternion Matrix and Groebner Base 被引量:1
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作者 Zhensong Ni Ruikun Wu 《Advances in Linear Algebra & Matrix Theory》 2018年第1期33-40,共8页
This article proposes a new algorithm of quaternion and dual quaternion in matrix form. It applies quaternion in special cases of rotated plane, transforming the sine and cosine of the rotation angle into matrix form,... This article proposes a new algorithm of quaternion and dual quaternion in matrix form. It applies quaternion in special cases of rotated plane, transforming the sine and cosine of the rotation angle into matrix form, then exporting flat quaternions base in two matrix form. It establishes serial 6R manipulator kinematic equations in the form of quaternion matrix. Then five variables are eliminated through linear elimination and application of lexicographic Groebner base. Thus, upper bound of the degree of the equation is determined, which is 16. In this way, a 16-degree equation with single variable is obtained without any extraneous root. This is the first time that quaternion matrix modeling has been used in 6R robot inverse kinematics analysis. 展开更多
关键词 6r rOBOT QUATErNION MATrIX Groebner base INVErSE KINEMATICS Analysis
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An Improved Double r-iteration IOD Method for GEO UCTs Based on SBSS System 被引量:2
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作者 TANG Yi ZHONG Wenan +1 位作者 LI Shuang SHOU Junming 《空间科学学报》 CAS CSCD 北大核心 2014年第6期867-871,共5页
The purpose of initial orbit determination,especially in the case of angles-only data for observation,is to obtain an initial estimate that is close enough to the true orbit to enable subsequent precision orbit determ... The purpose of initial orbit determination,especially in the case of angles-only data for observation,is to obtain an initial estimate that is close enough to the true orbit to enable subsequent precision orbit determination processing to be successful.However,the classical angles-only initial orbit determination methods cannot deal with the observation data whose Earth-central angle is larger than 360°.In this paper,an improved double r-iteration initial orbit determination method to deal with the above case is presented to monitor geosynchronous Earth orbit objects for a spacebased surveillance system.Simulation results indicate that the improved double r-iteration method is feasible,and the accuracy of the obtained initial orbit meets the requirements of re-acquiring the object. 展开更多
关键词 dOUBLE r-iteration Initial OrBITAL determination Geosynchronous object Uncorrelated TArGETS SPACE-based space surveillance
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Behavior recognition algorithm based on the improved R3D and LSTM network fusion 被引量:1
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作者 Wu Jin An Yiyuan +1 位作者 Dai Wei Zhao Bo 《High Technology Letters》 EI CAS 2021年第4期381-387,共7页
Because behavior recognition is based on video frame sequences,this paper proposes a behavior recognition algorithm that combines 3D residual convolutional neural network(R3D)and long short-term memory(LSTM).First,the... Because behavior recognition is based on video frame sequences,this paper proposes a behavior recognition algorithm that combines 3D residual convolutional neural network(R3D)and long short-term memory(LSTM).First,the residual module is extended to three dimensions,which can extract features in the time and space domain at the same time.Second,by changing the size of the pooling layer window the integrity of the time domain features is preserved,at the same time,in order to overcome the difficulty of network training and over-fitting problems,the batch normalization(BN)layer and the dropout layer are added.After that,because the global average pooling layer(GAP)is affected by the size of the feature map,the network cannot be further deepened,so the convolution layer and maxpool layer are added to the R3D network.Finally,because LSTM has the ability to memorize information and can extract more abstract timing features,the LSTM network is introduced into the R3D network.Experimental results show that the R3D+LSTM network achieves 91%recognition rate on the UCF-101 dataset. 展开更多
关键词 behavior recognition three-dimensional residual convolutional neural network(r3d) long short-term memory(LSTM) drOPOUT batch normalization(BN)
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Can environmental regulation promote industrial innovation and productivity?Based on the strong and weak Porter hypothesis 被引量:7
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作者 Baolong Yuan Kun Zhang 《Chinese Journal of Population,Resources and Environment》 2017年第4期322-336,共15页
This paper constructed extended CDM model to study the effects of environmental regulation on industrial innovation and productivity based on the perspective of strong and weak "Porter hypothesis",by using 2... This paper constructed extended CDM model to study the effects of environmental regulation on industrial innovation and productivity based on the perspective of strong and weak "Porter hypothesis",by using 28 manufacturing industry panel data of 2003-2014. The findings reveal that:(1) the impact of environmental regulation on R&D intensity lags behind. In the long run,environmental regulation intensity has a significant role in promoting R&D investment in manufacturing industry.(2) The R&D has a significant role in promoting the substantial innovation of manufacturing industry, and has a strong lag and continuity. However, the R&D intensity has no obvious effect on strategic innovation of manufacturing industry.(3) The substantial innovation doesn't significantly promote the economic performance of manufacturing industry, but it has a significant role in promoting the energy performance of manufacturing industry, and the substantial innovation plays a significant role in promoting environmental performance in the long term. The strategic innovation significantly promotes the economic performance of manufacturing industry, and it inhibits the energy performance and has no significant effect on environmental performance in the short term. It can promote the energy performance of manufacturing industry, but significantly inhibit environmental performance in the long term.(4) Environmental regulation has significantly suppressed the substantive innovation and strategic innovation of manufacturing industry, and the weak Porter hypothesis has not yet been supported. In the short term, environmental regulation inhibits manufacturing economic performance, but it can promote energy and environmental performance. In the long run, environmental regulation promotes the economic and energy performance of manufacturing industry, but it inhibits environmental performance. The establishment of strong Porter hypothesis has a certain scenario. 展开更多
关键词 Environmental regulationsubstantial innovation strategic innovation PrOdUCTIVITY Porterhypothesis CdM model
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3DV quality model based depth maps for view synthesis in FTV system
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作者 张秋闻 安平 +2 位作者 张艳 张兆杨 王元庆 《Journal of Shanghai University(English Edition)》 CAS 2011年第4期335-341,共7页
Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems. When depth maps are derived using existing depth estimation methods, the depth distortions will cause undesirable artifacts ... Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems. When depth maps are derived using existing depth estimation methods, the depth distortions will cause undesirable artifacts in the synthesized views. To solve this problem, a 3D video quality model base depth maps (D-3DV) for virtual view synthesis and depth map coding in the FTV applications is proposed. First, the relationships between distortions in coded depth map and rendered view are derived. Then, a precisely 3DV quality model based depth characteristics is develop for the synthesized virtual views. Finally, based on D-3DV model, a multilateral filtering is applied as a pre-processed filter to reduce rendering artifacts. The experimental results evaluated by objective and subjective methods indicate that the proposed D-3DV model can reduce bit-rate of depth coding and achieve better rendering quality. 展开更多
关键词 free-viewpoint television (FTV) 3d video quality model base depth maps d-3dV) view synthesis
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A Method for Preparation of Ordered Porous Silicon Based on a 2D SiO_2 Template
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作者 吴英 翟晓霞 +3 位作者 甄聪棉 刘晓伟 马丽 侯登录 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期127-130,共4页
A new method for fabricating ordered porous silicon is reported. A two-dimensional silica nanosphere array is used as a template with a hydrofluoric acid-hydrogen peroxide solution for etching the nanospheres. The ini... A new method for fabricating ordered porous silicon is reported. A two-dimensional silica nanosphere array is used as a template with a hydrofluoric acid-hydrogen peroxide solution for etching the nanospheres. The initial diameter and distribution of the holes in the resulting porous silicon layer are determined by the size and distribution of the silica nanospheres. The corrosion time can be used to control the depths of the holes. It is found that the presence of a SiO2 layer, formed by the oxidation of the rough internal surface of the hole, is the primary reason allowing the corrosion to proceed. Ultraviolet reflection and thermal conductivity measurements show that the diameter and distribution of the holes have a great influence on properties of the porous silicon. 展开更多
关键词 of is as A Method for Preparation of Ordered Porous Silicon based on a 2d SiO2 Template for in SIO that were on
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R & D project's investment evaluation based on real option and its value at risk
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作者 沈玉志 周效飞 《Journal of Coal Science & Engineering(China)》 2003年第2期124-126,共3页
The authors looked upon it as real options and applied the VaR(Value at Risk) method to the evaluation of its risk value based on the analysis of R & D project investment characteristics,and advanced the evaluatio... The authors looked upon it as real options and applied the VaR(Value at Risk) method to the evaluation of its risk value based on the analysis of R & D project investment characteristics,and advanced the evaluation model of the project’s return and risk according to financial theories.This paper expounded the two dimension evaluation model of project,and divided it into five decision making regions. 展开更多
关键词 r & d project real option VAr two dimension evaluation
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A RPC test station based on ROOT and VME
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作者 Zhi-Peng Lu Qing-Min Zhang +7 位作者 Jie Zhao Jia-Wen Zhang Yu-Guang Xie Sen Qian Zhe Ning Jeremiah Monari Kebwaro Yu-Chi Chen Zi-Xing He 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第2期79-85,共7页
Due to its advantages in large-area application situations, the R&D of the resistive plate chamber(RPC)has always been carried out. A performance test station for RPC R&D has been designed and developed based ... Due to its advantages in large-area application situations, the R&D of the resistive plate chamber(RPC)has always been carried out. A performance test station for RPC R&D has been designed and developed based on the VME bus and ROOT in Linux. This system can be customized expediently according to the requirements of different tests, which facilitates detector R&D because of its automatic HV scan, especially for long-term test. With this system, we have implemented the RPC performance test,including the efficiency curve, counting rate, dark current and charge and timing resolution. 展开更多
关键词 VME总线 rPC 试验站 Linux 性能试验台 时间分辨率 长期试验 性能测试
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Framework to Design Type-based Transfer Processes Between Technology and Product Development
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作者 Guenther Schuh Katharina Apfel 《Management Studies》 2014年第6期357-372,共16页
To stay globally competitive, manufacturing companies are increasingly under pressure to bring new products and applications to market, improve existing products, and discover new technologies to produce them at a low... To stay globally competitive, manufacturing companies are increasingly under pressure to bring new products and applications to market, improve existing products, and discover new technologies to produce them at a lower price. New technological findings can enable companies to overcome these challenges. In practice, technology development associated with a long time horizon is often given a lower priority compared with short-term focused product development thus being stronger restricted by everyday business. More and more companies separate their technology development department from product development to promote technological innovations. Due to this additional interface in the R&D organization new problems arise, resulting in technologies not being implemented in products. The reasons for these problems amongst others concern wrong timing for the transfer or inadequate definition of responsibilities. In this paper of ongoing research, authors introduce a framework to design the transfer processes between technology development and product development. Although there are a number of options for designing the operative transfer, there is no regulatory framework specifying which configuration options are at this particular interface. The approach is to develop a model, which is able to design different company-specific transfer processes taking into account the object being transferred at this interface. Thus, for different objects to be transferred, different transfer processes are designed. The model's aim is to enable responsibility of the R&D management to design their company-specific transfer processes to enable more technologies being implemented into products, thus giving the whole company the possibility to act more innovatively. 展开更多
关键词 technology development product development interface management rd management
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High-Frequency Guided Wave Scattering by a Partly Through-Thickness Hole Based on 3D Theory
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作者 张海燕 徐建 马世伟 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第8期94-97,共4页
We present a theoretical investigation of the scattering of high frequency S0 Lamb mode from a circular blind hole defect in a plate based on the 3D theory. The SO wave is incident at the frequency above the A1 mode c... We present a theoretical investigation of the scattering of high frequency S0 Lamb mode from a circular blind hole defect in a plate based on the 3D theory. The SO wave is incident at the frequency above the A1 mode cut-off frequency, in which the popular approximate plate theories are inapplicable. Due to the non-symmetric blind hole defect, the scattered fields will contain higher order converted modes in addition to the fundamental SO and AO modes. The far-field scattering amplitudes of various propagating Lamb modes for different hole sizes are inspected. The results are compared with those of lower frequencies and some different phenomena are found. Two-dimensional Fourier transform (2DFT) results of transient scattered Lamb and SH wave signals agree well with the analytical dispersion curves, which check the validity of the solutions from another point of view. 展开更多
关键词 High-Frequency Guided Wave Scattering by a Partly Through-Thickness Hole based on 3d Theory
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The Impact of Debt Financing on Corporate R & D Investment Behavior in China ——Based on the Empirical Evidence of Listed Companies from 2004 to 2011
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作者 Shengqiang LIU Dandan CHANG 《International English Education Research》 2015年第11期59-63,共5页
Base on panel data of manufacturing and high-tech industry companies which discoursed R & D expenditure in financial statements from 2004 to 2011, this paper studies the relationship between debt financing and corpor... Base on panel data of manufacturing and high-tech industry companies which discoursed R & D expenditure in financial statements from 2004 to 2011, this paper studies the relationship between debt financing and corporate R & D expenditure under different grow opportunities by using the robust fixed effects that Daniel Hoechle proposed m 2007. The results show that there is not a "increasing first, decreasing later" non-linear relationship but a "double negative" relationship between debt level and corporate R & D expenditure. And the "double negative" relationship has a different mechanism in different growth companies. 展开更多
关键词 debt Financing r d Investment Fixed Effects
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