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Semantic model and optimization of creative processes at mathematical knowledge formation
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作者 Victor Egorovitch Firstov 《Natural Science》 2010年第8期915-922,共8页
The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the ... The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the formation of deductive theory is represented as the development of a certain informational space, the elements of which are structured in the form of the orientated semantic net. This net is properly metrized and characterized by a certain system of coverings. It allows injecting net optimization parameters, regulating qualitative aspects of knowledge system under consideration. To regulate the creative processes of the formation and realization of mathematical know- edge, stochastic model of formation deductive theory is suggested here in the form of branching Markovian process, which is realized in the corresponding informational space as a semantic net. According to this stochastic model we can get correct foundation of criterion of optimization creative processes that leads to “great main points” strategy (GMP-strategy) in the process of realization of the effective control in the research work in the sphere of mathematics and its applications. 展开更多
关键词 The Cybernetic Conception optimization of CONTROL Quantitative And Qualitative Information Measures Modelling Intellectual Systems Neural Network MATHEMATICAL Education The CONTROL of Pedagogical PROCESSES CREATIVE Pedagogics Cognitive And CREATIVE PROCESSES Informal Axiomatic Thery SEMANTIC NET NET optimization Parameters The Topology of SEMANTIC NET Metrization The System of Coverings Stochastic Model of CREATIVE PROCESSES At The Formation of MATHEMATICAL Knowledge Branching Markovian Process Great Main Points Strategy (GMP-Strategy) of The CREATIVE PROCESSES CONTROL Interdisciplinary Learning: Colorimetric Barycenter
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西藏交通警察道路执法工作的风险与防范
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作者 尼桑拉 《时代汽车》 2024年第12期184-186,共3页
西藏自治区自然、地理与气候环境复杂且特殊,道路交通环境相对恶劣,这导致当地交通警察道路执法工作面临诸多风险,包括警员人身安全和执法效能等风险。对此,文章对西藏交通警察道路执法工作风险进行了调查分析,从地区环境、警员安全意... 西藏自治区自然、地理与气候环境复杂且特殊,道路交通环境相对恶劣,这导致当地交通警察道路执法工作面临诸多风险,包括警员人身安全和执法效能等风险。对此,文章对西藏交通警察道路执法工作风险进行了调查分析,从地区环境、警员安全意识与技能、执法装备、社会宣传和教育等角度探讨了相关风险的成因,针对性相关风险成因,提出从优化警力配置与道路信息推送、加强警员培训、完善警务装备、加强法治化宣传教育等工作来消除相关风险,以期保障警员安全并改善西藏交通环境。 展开更多
关键词 西 harsh which leads to the local trac POLICE road LAW ENFORCEMENT work to face a lot of RISKS including the personal SAFETY of the POLICE ocers and LAW ENFORCEMENT eectiveness and other risks. In this regard this paper investigates and analyzes the RISKS of road LAW ENFORCEMENT work of the Xi Zang trac POLICE discusses the causes of the RISKS from the perspectives of regional environment POLICE SAFETY awareness and skills LAW ENFORCEMENT equipment social publicity and education and proposes to eliminate the RISKS by optimizing the allocation of POLICE force and road information delivery strengthening POLICE training improving POLICE equipment and strengthening the rule of LAW publicity and education etc. so as to guarantee the SAFETY of POLICE ocers and improve the eectiveness of LAW ENFORCEMENT so as to ensure the SAFETY of POLICE ocers and improve the trac environment in Xi Zang.
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Economic Performance Optimization of a PV-BESS Power Generator: A Case Study La Reunion Island
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作者 Cédric Damour Michel Benne +2 位作者 Frédéric Alicalapa Brigitte Grondin-Perez Jean-Pierre Chabriat 《Smart Grid and Renewable Energy》 2017年第4期114-128,共15页
This paper proposes an economic performance optimization strategy for a PV plant coupled with a battery energy storage system. The case study of La Reunion Island, a non-interconnected zone (NIZ) with a high level of ... This paper proposes an economic performance optimization strategy for a PV plant coupled with a battery energy storage system. The case study of La Reunion Island, a non-interconnected zone (NIZ) with a high level of renewable energy sources (RES), is considered. This last decade, to reach the ambitious target of electricity autonomy by 2030 set by the local authorities, local and national plans have been launched to promote renewable energy sources integration that led to a noticeable development of photovoltaic (PV) systems. To avoid a decrease of the grid reliability due to a large integration of intermittent energy sources into a non-interconnected grid, the authorities have introduced new regulatory rules for RES producers. The proposed optimization strategy relies on these new regulatory rules and takes into account the energy market data, the amount of PV production subject to penalties for imbalance, the batteries and the PV technological characteristics together with a PV production forecast model. Due to its high convergence rate to the true global minimum and its perfect suitability to practical engineering optimization problems, the recently developed Modified Cuckoo Search algorithm is used as optimization algorithm. The effectiveness and relevance of the proposed strategy are assessed on experimental data collected on a real PV power plant. An economical analysis demonstrates that the proposed optimization strategy is able to fulfill the new regulatory rules requirements while increasing the economic performance of the system. 展开更多
关键词 Power SYSTEM ECONOMIC Analysis and optimization PV Plant Battery Energy Storage SYSTEM METAHEURISTIC optimization Algorithm
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Gas Turbine Performance Optimization Using Compressor Online Water Washing Technique
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作者 Ezenwa A. Ogbonnaya 《Engineering(科研)》 2011年第5期500-507,共8页
The ability to predict the behaviour of a gas turbine engine and optimize its performance is critical in eco-nomic, thermal and condition monitoring studies. Having identified fouling as one of the major sources of co... The ability to predict the behaviour of a gas turbine engine and optimize its performance is critical in eco-nomic, thermal and condition monitoring studies. Having identified fouling as one of the major sources of compressor and therefore gas turbine deterioration, a computer-based engine model was developed to optimize the performance of gas turbines. The paper thus presents an analysis of compressor hand cleaning, on and offline compressor washing to actualize the technique using a computer program in Visual Basic programming language with data collected over a period of fifteen weeks for 2 gas turbine plants GT1 and GT2. The results of the data collected, when collated, shows that after washing, the overall operational efficiency changed from 39.2% to 46.25%. To optimize the performance of gas turbine engines, it is therefore recommended that operators should perform a combination of compressor hand cleaning, offline and online washing simultaneously. 展开更多
关键词 Gas TURBINE TURBOMACHINERY Components FOULING performance optimization Operational PRACTICES COMPRESSOR Water WASHING
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Using of Particle Swarm for Performance Optimization of Helicopter Rotor Blades
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作者 Giorgio Guglieri 《Applied Mathematics》 2012年第10期1403-1408,共6页
As part of a research activity at Politecnico di Torino, aiming to develop multi-disciplinary design procedures implementing nature inspired meta-heuristic algorithms, a performance design optimization procedure for h... As part of a research activity at Politecnico di Torino, aiming to develop multi-disciplinary design procedures implementing nature inspired meta-heuristic algorithms, a performance design optimization procedure for helicopter rotors has been developed and tested. The procedure optimizes the aerodynamic performance of blades by selecting the point of taper initiation, the root chord, the taper ratio, and the maximum twist which minimize horsepower for different flight regimes. Satisfactory aerodynamic performance is defined by the requirements which must hold for any flight condition: the required power must be minimized, both the section drag divergence Mach number on the advancing side of the rotor disc and the maximum section lift coefficient on the retreating side of the rotor disc must be avoided and, even more important, the rotor must be trimmed. The procedure uses a comprehensive mathematical model to estimate the trim states of the helicopter and the optimization algorithm consists of a repulsive particle swarm optimization program. A comparison with an evolutionary micro-genetic algorithm is also presented. 展开更多
关键词 HELICOPTER FLIGHT MECHANICS NATURE Inspired META-HEURISTIC Algorithms Optimal Design Methods
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A PID Tuning Approach for Inertial Systems Performance Optimization
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作者 Irina Cojuhari 《Applied Mathematics》 2024年第1期96-107,共12页
In the practice of control the industrial processes, proportional-integral-derivative controller remains pivotal due to its simple structure and system performance-oriented tuning process. In this paper are presented ... In the practice of control the industrial processes, proportional-integral-derivative controller remains pivotal due to its simple structure and system performance-oriented tuning process. In this paper are presented two approaches for synthesis the proportional-integral-derivative controller to the models of objects with inertia, that offer the procedure of system performance optimization based on maximum stability degree criterion. The proposed algorithms of system performance optimization were elaborated for model of objects with inertia second and third order and offer simple analytical expressions for tuning the PID controller. Validation and verification are conducted through computer simulations using MATLAB, demonstrating successful performance optimization and showcasing the effectiveness PID controllers’ tuning. The proposed approaches contribute insights to the field of control, offering a pathway for optimizing the performance of second and third-order inertial systems through robust controller synthesis. 展开更多
关键词 PID Control Algorithm Inertial Systems System performance optimization Maximum Stability Degree
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Retro-Reflective Fiber Optic Displacement Sensor for Performance Optimization Using Taguchi Method 被引量:2
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作者 Supriya S. Patil A. D. Shaligram 《Journal of Sensor Technology》 2020年第1期1-13,共13页
Fiber optic displacement sensors are widely used in industry. Retro reflective fiber optic displacement sensor consists of parallel fibers with a reflector at a distance. Light is launched into the transmitting fiber ... Fiber optic displacement sensors are widely used in industry. Retro reflective fiber optic displacement sensor consists of parallel fibers with a reflector at a distance. Light is launched into the transmitting fiber which gets reflected by reflector. This reflected light is collected by the receiving fiber. The received light is function of the displacement of the reflector from the fiber end faces. This paper is targeted to obtain a robust design for the fiber optic displacement sensor (FODS) using well known Taguchi method. The design takes care of all noise parameters within constraints of manufacturing tolerances. The statistical data analysis is performed on the simulated results. The larger the better signal to noise quality characteristics is used to find the effect of control parameters in the data analysis. Taguchi analysis suggests dominant parameters, which affects the sensitivity of the FODS and causes immunity to noise. A source fiber inclination angle is chosen as an adjustment parameter. Other control parameters are used for fine tuning of the FODS design for achieving three qualities viz. best robustness, optimized sensitivity and robustness and best sensitivity. 展开更多
关键词 Retroreflective FIBER OPTIC SENSOR Taguchi Method optimization of SENSOR GEOMETRY
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Study on the Performance Optimization of Knitted Fabric Anti-Roll by Tissue Structure
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作者 Guoqiang Chen Yanan Zhu 《Journal of Materials Science and Chemical Engineering》 2018年第4期1-5,共5页
Will use the same number of positive and negative coil longitudinal organization of fabric is ta edge sex used in the work of the organization to warp fabric edge sex, between restrained knitting principle, design a k... Will use the same number of positive and negative coil longitudinal organization of fabric is ta edge sex used in the work of the organization to warp fabric edge sex, between restrained knitting principle, design a kind of weft basketwork weaving method, especially in weft knitting machine woven from has the edge of weft knitted fabric performance weaving method. In order to overcome the existing technology aims to make weft basketwork structure of a single organization, edge sex is bad, or can’t produce rich weft knitted fabric appearance of shortage, provide a resistance to edge weft knitted fabric weaving method. 展开更多
关键词 ORGANIZATIONAL Structure KNITTED FABRIC RESISTANCE to EDGE performance optimization
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From EBIT to SEBIT(Sustainable EBIT):Sustainable Performance Accounting(SPA)Using the Example of CO_(2) Accounting
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作者 Knut Henkel Jenny Lay-Kumar Christian Hiß 《Journal of Modern Accounting and Auditing》 2024年第2期49-71,共23页
Corporate sustainability reporting has become increasingly important in recent years.However,conventional approaches reach their limits when it comes to quantifying and measuring the actual sustainability performance ... Corporate sustainability reporting has become increasingly important in recent years.However,conventional approaches reach their limits when it comes to quantifying and measuring the actual sustainability performance of a company.This article presents a new approach:Sustainable Performance Accounting(SPA),which is based on an extension of bookkeeping by including ESG bookkeeping.SPA enables companies to systematically measure and manage their sustainability performance.The article provides an overview of the basics of SPA methodology and uses a comprehensive example showing how SPA can be implemented in practice.The article is aimed at interested readers from science and practice as well as decision-makers who are interested in future-oriented sustainability reporting. 展开更多
关键词 CO_(2)accounting CO_(2)emissions CSRD ESG(Environmental Social Governance) ESG bookkeeping ESG provision ESG asset ESRS integrated financial reporting internalisation of external effects connectivity monetisation of ESG issues sustainability sustainability indicators negative emissions sequestration performance Sustainable performance Accounting(SPA)
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Data mining optimization of laidback fan-shaped hole to improve film cooling performance 被引量:2
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作者 WANG Chun-hua ZHANG Jing-zhou ZHOU Jun-hui 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1183-1189,共7页
To improve the cooling performance, shape optimization of a laidback fan-shaped film cooling hole was performed. Three geometric parameters, including hole length, lateral expansion angle and forward expansion angle, ... To improve the cooling performance, shape optimization of a laidback fan-shaped film cooling hole was performed. Three geometric parameters, including hole length, lateral expansion angle and forward expansion angle, were selected as the design parameters. Numerical model of the film cooling system was established, validated, and used to generate 32 groups of training samples. Least square support vector machine(LS-SVM) was applied for surrogate model, and the optimal design parameters were determined by a kind of chaotic optimization algorithm. As hole length, lateral expansion angle and forward expansion angle are 90 mm, 20° and 5°, the area-averaged film cooling effectiveness can reach its maximum value in the design space. LS-SVM coupled with chaotic optimization algorithm is a promising scheme for the optimization of shaped film cooling holes. 展开更多
关键词 gas TURBINE laidback fan-shaped film COOLING HOLES optimization support vector machine (SVM) CHAOTIC optimization algorithm
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Research on Performance Optimization of Spark Distributed Computing Platform
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作者 Qinlu He Fan Zhang +2 位作者 Genqing Bian Weiqi Zhang Zhen Li 《Computers, Materials & Continua》 SCIE EI 2024年第5期2833-2850,共18页
Spark,a distributed computing platform,has rapidly developed in the field of big data.Its in-memory computing feature reduces disk read overhead and shortens data processing time,making it have broad application prosp... Spark,a distributed computing platform,has rapidly developed in the field of big data.Its in-memory computing feature reduces disk read overhead and shortens data processing time,making it have broad application prospects in large-scale computing applications such as machine learning and image processing.However,the performance of the Spark platform still needs to be improved.When a large number of tasks are processed simultaneously,Spark’s cache replacementmechanismcannot identify high-value data partitions,resulting inmemory resources not being fully utilized and affecting the performance of the Spark platform.To address the problem that Spark’s default cache replacement algorithm cannot accurately evaluate high-value data partitions,firstly the weight influence factors of data partitions are modeled and evaluated.Then,based on this weighted model,a cache replacement algorithm based on dynamic weighted data value is proposed,which takes into account hit rate and data difference.Better integration and usage strategies are implemented based on LRU(LeastRecentlyUsed).Theweight update algorithm updates the weight value when the data partition information changes,accurately measuring the importance of the partition in the current job;the cache removal algorithm clears partitions without useful values in the cache to releasememory resources;the weight replacement algorithm combines partition weights and partition information to replace RDD partitions when memory remaining space is insufficient.Finally,by setting up a Spark cluster environment,the algorithm proposed in this paper is experimentally verified.Experiments have shown that this algorithmcan effectively improve cache hit rate,enhance the performance of the platform,and reduce job execution time by 7.61%compared to existing improved algorithms. 展开更多
关键词 SPARK memory optimization memory replacement strategy
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Analysis of Waste-Rock Transportation Process Performance in an Open-Pit Mine Based on Statistical Analysis of Cycle Times Data 被引量:1
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作者 Samwel Victor Manyele 《Engineering(科研)》 2017年第7期649-679,共31页
In this paper, the performance of a waste rock transportation process in an open pit mine was assessed by using cycle time data. A computerized truck-excavator dispatch system was used to record the cycle times. The p... In this paper, the performance of a waste rock transportation process in an open pit mine was assessed by using cycle time data. A computerized truck-excavator dispatch system was used to record the cycle times. The process was broken into seven steps (or components of the total cycle), durations of which were recorded for a period of 1 month, leading to N = 60,690 data points or dispatches. The open pit mine studied consisted of 12 waste types loaded by 14 excavators and hauled by 49 trucks (at a trucks-to-excavator ratio of 3.5:1) in 75 changing locations. The string-type data was coded using integers to allow a FORTRAN code to extract process performance parameters using statistical analysis. The study established a wide range of parameters including: the waste material generation rate (about 1.73 million t/month, 81% comprising waste rock), truck fill factor, f, total cycle time (Tct), production capacity, theoretical cycle time, non-productive cycle time Tnp, and cycle time performance ratio (CTPR), denoted as Tpr. The factors affecting the process performance include: truck model, excavator model, location (haul distance and road conditions) and material type. For a fixed material type and tonnage, the PDFs of the cycle time components were logarithmic in nature, capable of differentiating performance variations under different factors. It was concluded that the performance of the waste material transportation system in this mine was determined to be acceptable due to mean value of Tpr = 2.432 being closer to unity. Reduction measures were suggested to minimize the cycle time for the process bottlenecks determined from Pareto analysis (that is, full haul, empty haul and loading processes). 展开更多
关键词 Potentially Acid-Forming (PAF) ROCK Non-Acid FORMING (NAF) ROCK TRUCK Utilization TRUCK Fill-Factor QUEUING TIME Loading CYCLE TIME Full and Empty Haul Total CYCLE TIME Theoretical CYCLE TIME Non-Productive CYCLE TIME CYCLE TIME performance Ratio
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Development and Application of Decision Support Model for the Performance Optimization of Office Buildings Based on Grasshopper
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作者 Hui Ren Shoulong Wang 《Journal of Harbin Institute of Technology(New Series)》 CAS 2021年第4期1-15,共15页
With the expansion of the office building area,the energy consumption of office buildings is growing.High⁃performance building design contributes to energy saving and the development of green buildings.However,there i... With the expansion of the office building area,the energy consumption of office buildings is growing.High⁃performance building design contributes to energy saving and the development of green buildings.However,there is a lack of high⁃performance building tools and the workflow is often time⁃consuming.The building performance simulation,multiple objective optimizations,and the decision support model are the new approaches of high⁃performance building design.This paper proposes a newly developed decision support model,a high⁃performance building decision model named HPBuildingDSM,which integrates the building performance simulation,building performance multiple objective optimizations,building performance sampling,and parameter sensitivity analysis to design high⁃performance office buildings.In this research,the HPBuildingDSM was operated to search for the desirable office building design results with low⁃energy and high⁃quality daylighting performances.The simulated results had better daylighting performance and lower energy consumption,whose UDI100-2000 was 37.94%and annual energy consumption performance was 76.28 kWh/(m2·a),indicating a better building performance than the optimized results in the previous case study. 展开更多
关键词 decision support model building performance simulation building performance optimization building performance simulation sensitivity analysis HPBuildingDSM tool
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Investigation of Excavator Performance Factors in an Open-Pit Mine Using Loading Cycle Time
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作者 Samwel Victor Manyele 《Engineering(科研)》 2017年第7期599-624,共26页
This study presents the effect of excavator model, loading operation location, shift availability and truck-shovel combination on loading cycle time and productivity of an open-pit mine. The loading cycle time was use... This study presents the effect of excavator model, loading operation location, shift availability and truck-shovel combination on loading cycle time and productivity of an open-pit mine. The loading cycle time was used to assess the material loading system performance which is one of the key components of the total cycle time for material transportation in an open-pit mine. Loading is among the components of cycle time during which material is being handled. The data analyzed?was?collected from a computerized dispatch system at GGM from which 62,000 loading dispatches per month involving several shifts, 14 excavators and 49 trucks were loaded. About 4465 dispatches per excavator and 1276 dispatches per truck were assessed using loading cycle time data for each dispatch for a period of four months (between August and December). Under fixed tonnage loaded and waste type (33 t of non-acid forming waste rock),?it was observed that loading cycle time depends on excavator model, location and truck being loaded. Average cycle times, PDFS?and CDFS of loading cycle time series were used to identify differences in performance under different situations. It was concluded that shift availability for excavators, loading location, excavator model and truck-shovel combinations strongly affect the productivity during loading process in an open-pit mine. 展开更多
关键词 Potentially Acid-Forming (PAF) ROCK Non-Acid FORMING (NAF) ROCK TRUCK Utilization TRUCK Fill-Factor Queuing TIME LOADING CYCLE TIME Full and Empty Haul Total CYCLE TIME Theoretical CYCLE TIME Non-Productive CYCLE TIME CYCLE TIME performance Ratio
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Optimization of ambipolar current and analog/RF performance for T-shaped tunnel field-effect transistor with gate dielectric spacer
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作者 Ru Han Hai-Chao Zhang +1 位作者 Dang-Hui Wang Cui Li 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第1期656-662,共7页
A new T-shaped tunnel field-effect transistor(TTFET) with gate dielectric spacer(GDS) structure is proposed in this paper. To further studied the effects of GDS structure on the TTFET, detailed device characteristics ... A new T-shaped tunnel field-effect transistor(TTFET) with gate dielectric spacer(GDS) structure is proposed in this paper. To further studied the effects of GDS structure on the TTFET, detailed device characteristics such as current-voltage relationships, energy band diagrams, band-to-band tunneling(BTBT) rate and the magnitude of the electric field are investigated by using TCAD simulation. It is found that compared with conventional TTFET and TTFET with gate-drain overlap(GDO) structure, GDS-TTFET not only has the minimum ambipolar current but also can suppress the ambipolar current under a more extensive bias range. Furthermore, the analog/RF performances of GDS-TTFET are also investigated in terms of transconductance, gate-source capacitance, gate-drain capacitance, cutoff frequency, and gain bandwidth production. By inserting a low-κ spacer layer between the gate electrode and the gate dielectric, the GDS structure can effectively reduce parasitic capacitances between the gate and the source/drain, which leads to better performance in term of cutoff frequency and gain bandwidth production. Finally, the thickness of the gate dielectric spacer is optimized for better ambipolar current suppression and improved analog/RF performance. 展开更多
关键词 tunneling field effect TRANSISTOR T-SHAPED TUNNEL FIELD-EFFECT TRANSISTOR gate dielectric SPACER ambipolar current analog/RF performance
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CEE-Gr:A Global Router with Performance Optimization Under Multi-Constraints
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作者 张凌 经彤 +3 位作者 洪先龙 许静宇 XiongJinjun HeLei 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第5期508-515,共8页
A global routing algorithm with performance optimization under multi constraints is proposed,which studies RLC coupling noise,timing performance,and routability simultaneously at global routing level.The algorithm is... A global routing algorithm with performance optimization under multi constraints is proposed,which studies RLC coupling noise,timing performance,and routability simultaneously at global routing level.The algorithm is implemented and the global router is called CEE Gr.The CEE Gr is tested on MCNC benchmarks and the experimental results are promising. 展开更多
关键词 VLSI/ULSI physical design global routing multi constraints performance optimization
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New development in Fe/Co catalysts:Structure modulation and performance optimization for syngas conversion 被引量:4
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作者 Yinwen Li Xin Zhang Min Wei 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第8期1329-1346,共18页
C1 chemistry is the essence of coal chemistry and natural gas chemistry. Catalytic methods to efficiently convert C1 molecules into fuels and chemicals have been extensively studied. Syngas(CO +H_2) conversion is t... C1 chemistry is the essence of coal chemistry and natural gas chemistry. Catalytic methods to efficiently convert C1 molecules into fuels and chemicals have been extensively studied. Syngas(CO +H_2) conversion is the most important industrial reaction system in C1 chemistry, and Fe and Co catalysts, two major industrial catalysts, have been the focus of fundamental research and industrial application. In the last decade, considerable research efforts have been devoted to discoveries concerning catalyst structure and increasing market demands for olefins and oxygenates. Since the development of efficient catalysts would strongly benefit from catalyst design and the establishment of a new reaction system, this review comprehensively overviews syngas conversion in three main reactions, highlights the advances recently made and the challenges that remain open, and will stimulate future research activities. The first part of the review summarizes the breakthroughs in Fischer-Tropsch synthesis regarding the optimization of activity and stability, determination of the active phase, and mechanistic studies. The second part overviews the modulation of catalytic structure and product selectivity for Fischer-Tropsch to olefins(FTO). Catalysts designed to produce higher alcohols, as well as to tune product selectivity in C1 chemistry, are described in the third section. Finally, present challenges in syngas conversion are proposed, and the solutions and prospects are discussed from the viewpoint of fundamental research and practical application. This review summarizes the latest advances in the design, preparation, and application of Fe/Co-based catalysts toward syngas conversion and presents the challenges and future directions in producing value-added fuels. 展开更多
关键词 Syngas conversion Fe/Cocatalyst Structure modulation performance optimization Product selectivity
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Performance in Caribbean and African Literatures as Subversion of the Colonial Order
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作者 Marie-Dominique Boyce 《Journal of Literature and Art Studies》 2019年第2期155-163,共9页
In the past oral Caribbean and African cultures,performances by the“griots”reminded the community of its heroic past.In colonial studies,performance is a way for the colonized people to reconnect with its original s... In the past oral Caribbean and African cultures,performances by the“griots”reminded the community of its heroic past.In colonial studies,performance is a way for the colonized people to reconnect with its original soul and language and to become magnificent of creativity like the storyteller Solibo in Chamoiseau’s Solibo Magnifique(Caribbean).In Chamoiseau’s novel,the Black policemen who came to investigate on Solibo’s sudden death during the performance look grotesque.They mimic the French colonizers with their“baton”and their racism at thinking evil of the Black community and they provoke laughter.Mimicry and the irony it conveys,subverts the formerly ironclad authority of the colonial order(Homi K.Bhabha in Location of Culture).The Cameroonian writer Werewere Liking-Gnépo also warns the Africans of the danger of wearing the White Mask of the colonizers(like Fanon in Black Skin,White Masks).She demonstrates in her Song/Novel She will be of Jasper and Coral,that while the African Mask empowers the performer of metaphysical powers,the White Mask of colonialism on the contrary weakens the performer who internalizes his inferiority and becomes complicit of his subjugation.Fortunately,Werewere Liking-Gnépo shows ithat the White Mask of colonialism can be used to mimic the harshness and corruption of the Colonial order and in doing so to bring back regeneration of Africa. 展开更多
关键词 Caribbean LITERATURE African LITERATURE illocutory and kinetic forces of a performance(dance story-telling) conversion of performances into LITERATURE COLONIALISM SUBVERSION of COLONIALISM Fanon Chamoiseau Werewer Liking-Gnépo Bhabha the Colonizer and the Colonized
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Use of Stone Dust in the Design of High Performance Concrete
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作者 Joffrey Cheruiyot Sylvester Ochieng Abuodha Charles Kabubo 《Open Journal of Civil Engineering》 2014年第3期229-239,共11页
This research evaluated the suitability of stone dust in the design and production of High Perfor-mance Concrete (HPC). HPC mix was designed, tested, costed and a comparison of concrete classes used in the market (Cla... This research evaluated the suitability of stone dust in the design and production of High Perfor-mance Concrete (HPC). HPC mix was designed, tested, costed and a comparison of concrete classes used in the market (Class 25, 30 and 35) done using Cost Benefit Analysis (CBA). The cost benefit was analyzed using Internal Rate of Return (IRR) and Net Present Value (NPV). Laboratory tests established the properties concrete obtained from the design mix. Compressive strength, slump, and modulus of elasticity were tested and analyzed. Structural analysis using BS 8110 was done for a 10 storey office building to establish the structural member sizes. Members obtained from concrete Classes 25, 30, 35 and the new compressive strengths from HPC (Class 80) were obtained and compared. Analysis was done for structural members’ sizes and area freed as a result of de-signing with HPC as well as the steel reinforcement used. To justify the initial cost of HPC if ado- pted, the Cost Benefit Analysis (CBA) was used to estimate increased costs versus income resulting from increased let table space created. The minimum class of concrete used in design was limited to Class 25 N/mm2. The research shows that it is possible to manufacture high strength concrete using locally available stone dust. The stone dust sampled from Mlolongo quarries achieved a characteristic strength of 86.7 N/mm2 at a water cement ratio of 0.32. With the results structural analysis of a 10 storey office structures with columns spaced at 8 meters center to center was de-signed using the four classes and results compared. There was a reduction of columns from 1.2 m wide to 0.65 m wide (over 45%) when concrete class changes from Class 25 to Class 80 creating over 3% of the total space area per floor. Cost benefit analysis using Net Present Value (NPV) and Internal Rate of Return (IRR) presented business case for the use of HPC. With Class 80, the IRR was at 3% and NPV being 8% of the total initial investment. The steel reinforcement increased by 8.64% using Class 30, 11.68% using Class 35 and reduced by 8.37% at Class 80. Further analysis needs to be done to understand the trend of steel reinforcement keeping all the member sizes the same. In this study the member sizes were optimized based on the steel reinforcement and serviceability. This paper provides useful information to design Engineers and Architects and inform future design of multi storey structures. 展开更多
关键词 High performance Concrete (HPC) Locally Produced QUARRY DUST Properties Cost BENEFIT Analysis (CBA) Net Present Value (NPV) Internal Rate of Return (IRR)
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Mechanical Analysis and Performance Optimization for the Lunar Rover’s Vane-Telescopic Walking Wheel 被引量:1
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作者 Lu Yang Bowen Cai +5 位作者 Ronghui Zhang Kening Li Zixian Zhang Jiehao Lei Baichao Chen Rongben Wang 《Engineering》 SCIE EI 2020年第8期936-943,共8页
It is well-known that optimizing the wheel system of lunar rovers is essential.However,this is a difficult task due to the complex terrain of the moon and limited resources onboard lunar rovers.In this study,an experi... It is well-known that optimizing the wheel system of lunar rovers is essential.However,this is a difficult task due to the complex terrain of the moon and limited resources onboard lunar rovers.In this study,an experimental prototype was set up to analyze the existing mechanical design of a lunar rover and improve its performance.First,a new vane-telescopic walking wheel was proposed for the lunar rover with a positive and negative quadrangle suspension,considering the complex terrain of the moon.Next,the performance was optimized under the limitations of preserving the slope passage and minimizing power consumption.This was achieved via analysis of the wheel force during movement.Finally,the effectiveness of the proposed method was demonstrated by several simulation experiments.The newly designed wheel can protrude on demand and reduce energy consumption;it can be used as a reference for lunar rover development engineering in China. 展开更多
关键词 Intelligent vehicle Vane-telescopic walking wheel performance optimization Vane spring Lunar rover
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