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Model for the Whole Roller Leveling Process of Plates with Random Curvature Distribution Based on the Curvature Integration Method 被引量:4
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作者 Ben Guan Chao Zhang +1 位作者 Yong Zang Yuan Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期145-155,共11页
A model based on the curvature integration method has been applied in an online plate leveling system. However, there are some shortcomings in the current leveling models. On the one hand, the models cannot deal with ... A model based on the curvature integration method has been applied in an online plate leveling system. However, there are some shortcomings in the current leveling models. On the one hand, the models cannot deal with the leveling process of plates with a random curvature distribution. On the other hand, the current models are suitable only for stable leveling processes and ignore the biting in and tailing out stages. This study presents a new plate-leveling model based on the curvature integration method, which can describe the leveling process of plates with random curvature distribution. Further, the model is solved in two cases in order to take the biting in and tailing out stages into consideration. The proposed model is evaluated by comparing with a plate leveling experiment. Finally, the leveling process of a plate with a wave bent is studied using the proposed model. It is found that the contact angles vary greatly during the biting in and tailing out stages. However, they are relatively steady during the 5 roller leveling stage. In addition, the contact angle of roller No. 2 is the smallest, which is close to 0. Roller leveling can effectively eliminate bending in the plate, but there are regions in the head and tail of the plate, where roller leveling is not effective. The non-leveling region length is about 2 times that of the roller space. This study proposes a quasi-static plate-leveling model, which makes it possible to analyze the dynamic straightening process using a curvature integration method. It also makes it possible to analyze the straightening process of a plate with random curvature distribution. 展开更多
关键词 levelING CURVATURE integration method CURVATURE Contact ANGLE DEFLECTION
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Boundary determination of leveling capacity for plate roller leveler based on curvature integration method 被引量:2
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作者 刘志芳 罗远新 +1 位作者 严兴春 王勇勤 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4608-4615,共8页
Leveler is widely used to improve the quality of defective mild steel plates.Its typical ranges of the leveling capacity are constrained by three criteria,namely the maximum stroke of rollers,allowable total leveling ... Leveler is widely used to improve the quality of defective mild steel plates.Its typical ranges of the leveling capacity are constrained by three criteria,namely the maximum stroke of rollers,allowable total leveling force and motor power.In this work,an optimization model with equality and inequality constraints was built for the maximum yield stress search of each thickness of plates.The corresponding search procedure with three loops was given.The approximate range by the simplification model could be used as the initial value for the actual range search of the leveling capacity.Therefore,the search speed could be accelerated compared with a global search.The consistency of the analytical results and field data demonstrates the reliability of the proposed model and procedure.The typical ranges of the leveling capacity are expressed by several boundary curves which are helpful to judge whether the incoming plate can be leveled quickly or not.Also,these curves can be used to find the maximum yield stress for a specific thickness or the maximum thickness for a yield stress for plates. 展开更多
关键词 plastic ratio leveling capacity curvature integration PLATE
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A Simple Weighted Integration Method for Calculating Surface Tension Force to Suppress Parasitic Flow in the Level Set Approach 被引量:1
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作者 王剑峰 杨超 毛在砂 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第6X期740-746,共7页
Parasitic flows may occur in the numerical simulation of incompressible multiphase flow due to errors in the calculation of surface tension terms, specifically for the curvature and unit normal vector. An improved met... Parasitic flows may occur in the numerical simulation of incompressible multiphase flow due to errors in the calculation of surface tension terms, specifically for the curvature and unit normal vector. An improved method for calculating the surface tension based on the level set approach is proposed, in which the contribution of not only the center node but also the rest area of a control volume to the calculation of surface tension is considered in a balanced manner. The weighted integration method (WIM) is more consistent with the concept of a banded in- terface in the level set method. It is applied to the temporal evolution of a two-dimensional neutrally buoyant liquid drop and a buoyancy driven deformable bubble in an immiscible fluid for the validation of WIM. The results show that the parasitic flows are evidently suppressed by the weighted integration method. The weight factors for WIM in 3-D cases are also suggested. 展开更多
关键词 PARASITIC FLOW WEIGHTED integration method SURFACE tension level set APPROACH numerical simulation
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Top-Level Design of Smart City Based on“Integration of Four Plans”
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作者 Jianbo Cheng Peng Sun 《ZTE Communications》 2015年第4期34-39,共6页
A smart city provides a new idea and model for urban construction, management, and development. This article proposes the concepts and methodology for top-level design of smart cities based on the " Integration of Fo... A smart city provides a new idea and model for urban construction, management, and development. This article proposes the concepts and methodology for top-level design of smart cities based on the " Integration of Four Plans ", and the planning process and systems for implementing the top-level design of smart cities. This article discusses, from the perspective of a city, how to optimize resource allocation, coordinate the development of urban economy, society, resources, environment, and people's livelihood, and map out the blueprints for healthy and sustainable development of a smart city. 展开更多
关键词 smart city top-level design integration of Four Plans ICT Benefiting People
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普职融通视域下英国T Level行动计划探究 被引量:5
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作者 吴雪萍 陈浊 吕乐瑶 《比较教育学报》 北大核心 2023年第1期17-32,共16页
T Level行动计划较为全面地体现出英国近年来提升职业技术教育地位、普通教育与职业教育并重的理念。此次英国推出T Level行动计划的动因在于英国劳动力市场需要更多中高级职业人才、职业技术教育需要提高社会认可度、义务教育阶段毕业... T Level行动计划较为全面地体现出英国近年来提升职业技术教育地位、普通教育与职业教育并重的理念。此次英国推出T Level行动计划的动因在于英国劳动力市场需要更多中高级职业人才、职业技术教育需要提高社会认可度、义务教育阶段毕业生需要体验职业教育。T Level行动计划主要由T Level项目、T Level过渡项目和T Level专业发展项目组成。T Level项目由各方共同设计,兼顾义务教育阶段毕业生的就业与升学;T Level过渡项目满足了义务教育阶段毕业生体验职业教育的需求;T Level专业发展项目为T Level项目实施提供保障。英国T Level行动计划的实施呈现出多元共治、删芜就简和问题导向等特点。借鉴英国T Level行动计划的经验,我国可通过引导雇主参与育人环节、基于项目式学习培养职业技能人才以及兼顾学生就业与升学等方式促进我国的普通教育与职业教育相互融通。 展开更多
关键词 普职融通 T level 义务教育阶段后教育 英国 项目式学习
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基于职普融通的英国T-Level资格考试制度及启示 被引量:1
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作者 蒋家琼 丁晨 《大学教育科学》 北大核心 2023年第6期85-94,共10页
职普融通是当前全球教育改革的潮流,职业教育高等化和高等教育职业化是21世纪国际教育发展的共同趋势。为推动职普融通,英国建立了T-Level资格考试制度,并于2022年开启了第一轮考试。围绕“谁来考、考什么、怎么考”等核心问题,T-Level... 职普融通是当前全球教育改革的潮流,职业教育高等化和高等教育职业化是21世纪国际教育发展的共同趋势。为推动职普融通,英国建立了T-Level资格考试制度,并于2022年开启了第一轮考试。围绕“谁来考、考什么、怎么考”等核心问题,T-Level资格考试制度形成了多元主体协同参与的考评主体、知识与技能并重的考评内容、纸笔考试与操作考试并行的考评方式。党和政府高度重视职业教育,提出要推进职普融通,加快构建现代职业教育体系。构建职教高考制度是我国推进职普融通、加快构建现代职业教育体系的重要举措。英国T-Level资格考试制度的经验,对于我国建立和完善职教高考制度、促进职普融通具有启示意义。当前,健全我国职教高考制度体系,需着力打破“横向融通”的体制性障碍,构建职普融通的有效通道;引导行业企业参与职教高考,提高职业教育社会认可度;完善职教高考内容与方式,构建职普融通考评体系。 展开更多
关键词 职普融通 现代职业教育体系 考试制度 T-level 英国
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Novel non-coherent integration method using binary phase-coded radar signal 被引量:2
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作者 田黎育 何苗 +1 位作者 刘斌 傅雄军 《Journal of Beijing Institute of Technology》 EI CAS 2013年第1期60-66,共7页
The m series with 511 bits is taken as an example being applied in non-coherent integra- tion algorithm. A method to choose the bi-phase code is presented, which is 15 kinds of codes are picked out of 511 kinds of m s... The m series with 511 bits is taken as an example being applied in non-coherent integra- tion algorithm. A method to choose the bi-phase code is presented, which is 15 kinds of codes are picked out of 511 kinds of m series to do non-coherent integration. It is indicated that the power in- creasing times of larger target sidelobe is less than the power increasing times of smaller target main- lobe because of the larger target' s pseudo-randomness. Smaller target is integrated from larger tar- get sidelobe, which strengthens the detection capability of radar for smaller targets. According to the sidelobes distributing characteristic, a method is presented in this paper to remove the estimated sidelobes mean value for signal detection after non-coherent integration. Simulation results present that the SNR of small target can be improved approximately 6. 5 dB by the proposed method. 展开更多
关键词 binary phase-coded signal non-coherent integration code agility peak sidelobe level(PSL) mainlobe-peak sidelobe ratio
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Integration-centric approach to system readiness assessment based on evidential reasoning 被引量:1
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作者 Leilei Chang Mengjun Li Ben Cheng Ping Zeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第6期881-890,共10页
An integration-centric approach is proposed to handle inadequate information in the system readiness level (SRL) assessment using the evidential reasoning (ER) algorithm. Current SRL assessment approaches cannot b... An integration-centric approach is proposed to handle inadequate information in the system readiness level (SRL) assessment using the evidential reasoning (ER) algorithm. Current SRL assessment approaches cannot be applied to handle inadequate information as the input. The ER-based approach is proposed to synthesize inadequate input information and an integration-centric perspective is applied to reduce the computational complexity. Two case studies are performed to validate the efficiency of the proposed approach. And these studies are also performed to study how the inadequate information will affect the assessment result. And the differences caused by the system's structure. The importance of the system's structure in the SRL assessment is demonstrated and the contributions made in this study are summarized as conclusions. 展开更多
关键词 system readiness level (SRL) technology readinesslevel (TRL) integration readiness level (IRL) evidential reasoning(ER) integration-centric.
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Integrated importance measure for multi-state coherent systems of k level 被引量:1
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作者 Xibin Zhao Shubin Si +2 位作者 Hongyan Dui Zhiqiang Cai Shudong Sun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期1029-1037,共9页
To verify the effectiveness of the integrated importance measure (IIM) for multi-state coherent systems of k level, the definition and physical meaning of IIM are demonstrated. Then, the improvement potential and Δ... To verify the effectiveness of the integrated importance measure (IIM) for multi-state coherent systems of k level, the definition and physical meaning of IIM are demonstrated. Then, the improvement potential and Δ-importance measures are generalized to multi-state coherent systems based on the system performance level, and the relationships between IIM and traditional importance measures are discussed. The characteristics of IIM are demonstrated in both series and parallel systems. Also, an application to an oil transportation system is given. The comparison results show that: (i) IIM has some useful properties that are not possessed by traditional importance measures; (ii) IIM is effective in evaluating the component role in multi-state systems when the component reliability and the failure rate are simultaneously considered. 展开更多
关键词 multi-state coherent system system performance level integrated importance measure system reliability
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MODIFIED INTEGRAL-LEVEL SET METHOD FOR THE CONSTRAINED SOLVING GLOBAL OPTIMIZATION 被引量:1
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作者 田蔚文 邬冬华 +1 位作者 张连生 李善良 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第2期202-209,共8页
The constrained global optimization problem being considered, a modified integral_level set method was illustrated based on Chew_Zheng's paper on Integral Global Optimization and (Wu's) paper on Implementable ... The constrained global optimization problem being considered, a modified integral_level set method was illustrated based on Chew_Zheng's paper on Integral Global Optimization and (Wu's) paper on Implementable Algorithm Convergence of Modified Integral_Level Set Method for Global Optimization Problem. It has two characters: 1) Each phase must construct a new function which has the same global optimal value as that of primitive objective function; 2) Comparing it with (Zheng's) method, solving level set procedure is avoided. An implementable algorithm also is given and it is proved that this algorithm is convergent. 展开更多
关键词 constrained global optimization integral-level set CONVERGENCE
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Novel Frame Shift and Integral Technique for Enhancing Low-Light-Level Moving Images
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作者 宋勇 郝群 王涌天 《Journal of Beijing Institute of Technology》 EI CAS 2006年第1期91-96,共6页
A novel frame shift and integral technique for the enhancement of low light level moving image sequence is introduced. According to the technique, motion parameters of target are measured by algorithm based on differe... A novel frame shift and integral technique for the enhancement of low light level moving image sequence is introduced. According to the technique, motion parameters of target are measured by algorithm based on difference processing. To obtain spatial relativity, images are shifted according to the motion parameters. As a result, the processing of integral and average can be applied to images that have been shifted. The technique of frame shift and integral that includes the algorithm of motion parameter determination is discussed, experiments with low light level moving image sequences are also described. The experiment results show the effectiveness and the robustness of the parameter determination algorithm, and the improvement in the signal-to-noise ratio (SNR) of low light level moving images. 展开更多
关键词 frame integral low light level image moving image sequence signal-to-noise ratio (SNR)
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Quick System-Level DDR3 Signal Integrity Simulation Research 被引量:2
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作者 Run-Jing Zhou Yuan-Yuan Hao Jin-Song Hu 《Journal of Electronic Science and Technology》 CAS 2013年第3期286-290,共5页
Double data rate synchronous dynamic random access memory (DDR3) has become one of the most mainstream applications in current server and computer systems. In order to quickly set up a system-level signal integrity ... Double data rate synchronous dynamic random access memory (DDR3) has become one of the most mainstream applications in current server and computer systems. In order to quickly set up a system-level signal integrity (SI) simulation flow for the DDR3 interface, two system-level SI simulation methodologies, which are board-level S-parameter extraction in the frequency-domain and system-level simulation assumptions in the time domain, are introduced in this paper. By comparing the flow of Speed2000 and PowerSI/Hspice, PowerSI is chosen for the printed circuit board (PCB) board-level S-parameter extraction, while Tektronix oscilloscope (TDS7404) is used for the DDR3 waveform measurement. The lab measurement shows good agreement between simulation and measurement. The study shows that the combination of PowerSI and Hspice is recommended for quick system-level DDR3 SI simulation. 展开更多
关键词 Index Terms--Double data rate synchronousdynamic random access memory HSPICE PowerSI signal integrity system-level signal integrity simulation.
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Multidisciplinary Design Optimization of A Human Occupied Vehicle Based on Bi-Level Integrated System Collaborative Optimization 被引量:4
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作者 赵敏 崔维成 李翔 《China Ocean Engineering》 SCIE EI CSCD 2015年第4期599-610,共12页
The design of Human Occupied Vehicle (HOV) is a typical multidisciplinary problem, but heavily dependent on the experience of naval architects at present engineering design. In order to relieve the experience depend... The design of Human Occupied Vehicle (HOV) is a typical multidisciplinary problem, but heavily dependent on the experience of naval architects at present engineering design. In order to relieve the experience dependence and improve the design, a new Multidisciplinary Design Optimization (MDO) method "Bi-Level Integrated System Collaborative Optimization (BLISCO)" is applied to the conceptual design of an HOV, which consists of hull module, resistance module, energy module, structure module, weight module, and the stability module. This design problem is defined by 21 design variables and 23 constraints, and its objective is to maximize the ratio of payload to weight. The results show that the general performance of the HOV can be greatly improved by BLISCO. 展开更多
关键词 Multidisciplinary Design Optimization (MDO) Human Occupied Vehicle (HOD Bi-level integrated SystemCollaborative Optimization (BLISCO) general performance
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Modeling Seasonal Fractionally Integrated Autoregressive Moving Average-Generalized Autoregressive Conditional Heteroscedasticity Model with Seasonal Level Shift Intervention
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作者 Lawrence Dhliwayo Florance Matarise Charles Chimedza 《Open Journal of Statistics》 2020年第5期810-831,共22页
This paper introduces the class of seasonal fractionally integrated autoregressive<span style="font-family:Verdana;"> moving average</span><span style="font-family:Verdana;">-<... This paper introduces the class of seasonal fractionally integrated autoregressive<span style="font-family:Verdana;"> moving average</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">generalized conditional heteroskedastisticty (SARFIMA-</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">GARCH) models, with level shift type intervention that are capable of capturing simultaneously four key features of time series: seasonality, long range dependence, volatility and level shift. The main focus is on modeling seasonal level shift (SLS) in fractionally integrated and volatile processes. A natural extension of the seasonal level shift detection test of the mean for a realization of time series satisfying SLS-SARFIMA and SLS-GARCH models w</span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> derived. Test statistics that are useful to examine if seasonal level shift in a</span><span style="font-family:Verdana;">n</span><span style="font-family:Verdana;"> SARFIMA-GARCH model </span><span style="font-family:Verdana;">is</span><span style="font-family:Verdana;"> statistically plausible were established. Estimation of SLS-SARFIMA and SLS-GARCH parameters w</span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> also considered.</span> 展开更多
关键词 SEASONALITY Fractional integration LONG-MEMORY level Shift SLS-SARFIMA SLS-GARCH VOLATILITY
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System integration and innovation of operating 20 kt combined heavy-haul train on Datong-Qinhuangdao line 被引量:2
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作者 Geng Zhixiu 《Engineering Sciences》 EI 2008年第3期12-26,共15页
Datong-Qinhuangdao line, as the first electrified double-track heavy-haul line dedicated to coal transport in China, extends from Datong in the west, and reaches Qinhuangdao in the east, opened to traffic in December,... Datong-Qinhuangdao line, as the first electrified double-track heavy-haul line dedicated to coal transport in China, extends from Datong in the west, and reaches Qinhuangdao in the east, opened to traffic in December, 1992, totaling 653 km with the designed annual traffic volume of 1×108 t. In order to meet the demands of national economic development, the transport capacity of the line must be enhanced greatly. Depending on independent innovation, MOR, for the first time in the world,realizes the integration between GSM-R and Locotrol, the integration between 800 MHz digital radio and Locotrol, and the integration between a single set of Locotrol and SS4 locomotive. Meanwhile, CR develops equipment portfolio for heavy-haul through combining 2 high power locomotives of HXD series (means harmony) with controllable EOT. Relying on integration and innovation, it succeeds in operating 20 kt-level combined heavy-haul train on Datong-Qinhuangdao line, which tripled the annual traffic volume of the line from 1×108 t in 2002 to 3×108 t in 2007. 展开更多
关键词 自主创新 联合经营 〇克拉 铁路线 统集成 SS4型机车 等效氧化层厚度 国民经济发展
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Co-Integration Models for Koyna and Warna Reservoirs, India
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作者 D. V. Ramana J. Pavan Kumar +1 位作者 R. N. Singh R. K. Chadha 《International Journal of Geosciences》 2015年第10期1173-1178,共6页
Koyna region, a seismically active region, has many time series observations such as seismicity, reservoir water levels, and many bore well water levels. One of these series is used to predict others since these param... Koyna region, a seismically active region, has many time series observations such as seismicity, reservoir water levels, and many bore well water levels. One of these series is used to predict others since these parameters are interlinked. If these series were stationary, we used correlation analysis. However, it is seen that maximum of these time series are nonstationary. In this case, co-integration method is used that is extracted from econometrics and forecast is possible. We have applied this methodology to study time series of reservoir water levels of this region and we find them to be co-integrated. Therefore, forecast of water levels for one of the reservoir is done from the other as these will never drift apart too much. The outcomes demonstrate that a joint modelling of both data sets based on underlying physics resolves to be sparingly useful for understanding predictability issues in reservoir induced seismicity. 展开更多
关键词 CO-integration SEISMICITY FORECAST Koyna-Warna RESERVOIRS Water levelS
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Hebei Talents Development Strategy under the Background of Talents Integration in Beijing-Tianjin-Hebei Region
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《International English Education Research》 2014年第1期19-23,共5页
关键词 人才开发 河北地区 一体化 北京 天津 区域经济合作 区域经济发展 经济可持续发展
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Adopting Context Mediation in Information Integration to Resolve Semantic Heterogeneity in Distributed Environment
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作者 周建芳 徐海银 卢正鼎 《Journal of Southwest Jiaotong University(English Edition)》 2008年第4期359-365,共7页
Ontology-based semantic information integration resolve the schema-level heterogeneity and part of data level heterogeneity between distributed data sources. But it is ubiquitous that schema semantics of information i... Ontology-based semantic information integration resolve the schema-level heterogeneity and part of data level heterogeneity between distributed data sources. But it is ubiquitous that schema semantics of information is identical while the interpretation of it varies with different context, and ontology-based semantic information integration can not resolve this context heterogeneity. By introducing context representation and context mediation to ontology based information integration, the attribute-level context heterogeneity can be detected and reconciled automatically, and hence a complete solution for semantic heterogeneity is formed. Through a concrete example, the context representation and the process in which the attribute-level context heterogeneity is reconciled during query processing are presented. This resolution can make up the deficiency of schema mapping based semantic information integration. With the architecture proposed in this paper the semantic heterogeneity solution is adaptive and extensive. 展开更多
关键词 Semantic information integration Schema semantics Attribute-level context heterogeneity Context conversion Context mediation
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基于Cadence Integrity 3D-IC的异构集成封装系统级LVS检查
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作者 张成 赵佳 李晴 《电子技术应用》 2023年第8期47-52,共6页
随着硅工艺尺寸发展到单纳米水平,摩尔定律的延续越来越困难。2D Flip-Chip、2.5D、3D等异构集成的先进封装解决方案将继续满足小型化、高性能、低成本的市场需求,成为延续摩尔定律的主要方向。但它也提出了新的挑战,特别是对于系统级的... 随着硅工艺尺寸发展到单纳米水平,摩尔定律的延续越来越困难。2D Flip-Chip、2.5D、3D等异构集成的先进封装解决方案将继续满足小型化、高性能、低成本的市场需求,成为延续摩尔定律的主要方向。但它也提出了新的挑战,特别是对于系统级的LVS检查。采用Cadence Integrity 3D-IC平台工具,针对不同类型的先进封装,进行了系统级LVS检查验证,充分验证了该工具的有效性和实用性,保证了异构集成封装系统解决方案的可靠性。 展开更多
关键词 异构集成 先进封装 系统级LVS integrity 3D-IC
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县域医共体医防融合实现机制与典型路径
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作者 胡美丽 张倩 +2 位作者 季文琦 杨雯 杨金兰 《卫生经济研究》 北大核心 2024年第5期69-73,共5页
目的:构建县域医共体医防融合实现机制,总结医防融合的典型路径,为其他地区开展基层医防融合提供借鉴和参考。方法:基于扎根理论并借助Nvivo软件进行数据编码及定性分析。结果:确定县域医共体开展医防融合的7个核心维度为体系融、管理... 目的:构建县域医共体医防融合实现机制,总结医防融合的典型路径,为其他地区开展基层医防融合提供借鉴和参考。方法:基于扎根理论并借助Nvivo软件进行数据编码及定性分析。结果:确定县域医共体开展医防融合的7个核心维度为体系融、管理融、服务融、人员融、信息融、绩效融和资金融,在实践中仅有少数县域医共体实现了较多维度的融合。结论:将服务融、管理融、信息融放在开展医防融合的首要位置,注重体系融和资金融的均衡设置,参考县域医共体医防融合实践的典型路径,进一步推动医防融合的发展。 展开更多
关键词 医防融合 县域医共体 扎根理论
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