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Development of database of real-world diesel vehicle emission factors for China

Journal of Environmental sciences 2015年第5期27卷 209-220页

作者： Xianbao Shen Zhiliang Yao Qiang Zhang David Vance Wagner Hong Huo Yingzhi Zhang Bo Zheng Kebin He State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University School of Food and Chemical Engineering Beijing Technology and Business University Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science Tsinghua University International Council on Clean Transportation (ICCT) Institute of Energy Environment and Economy Tsinghua University State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Tsinghua University

A database of real-world diesel vehicle emission factors, based on type and technology, has been developed following tests on more than 300 diesel vehicles in China using a portable emission measurement system. The database provides better understanding of diesel vehicle emissions under actual driving conditions. We found that although new regulations have reduced real-world emission levels of diesel trucks and buses significantly for most pollutants in China, NOx emissions have been inadequately controlled by the current standards, especially for diesel buses, because of bad driving conditions in the real world. We also compared the emission factors in the database with those calculated by emission factor models and used in inventory studies. The emission factors derived from COPERT（Computer Programmer to calculate Emissions from Road Transport） and MOBILE may both underestimate real emission factors, whereas the updated COPERT and PART5（Highway Vehicle Particulate Emission Modeling Software） models may overestimate emission factors in China. Real-world measurement results and emission factors used in recent emission inventory studies are inconsistent,which has led to inaccurate estimates of emissions from diesel trucks and buses over recent years. This suggests that emission factors derived from European or US-based models will not truly represent real-world emissions in China. Therefore, it is useful and necessary to conduct systematic real-world measurements of vehicle emissions in China in order to obtain the optimum inputs for emission inventory models.

关键词： Diesel vehicle Emission factor Portable emission measurement system Database China

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Weak-Model Based Reinforcement Learning Control Strategy of Aircraft Attitude system

Weak-Model Based Reinforcement Learning Control Strategy of ...

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International Conference on Guidance, Navigation and Control, ICGNC 2020

作者： Huang, Dingcui Hu, Jiangping Peng, Zhinan Hao, Mingrui School of Automation Engineering University of Electronic Science and Technology of China Chengdu611731 China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing100074 China

ISBN: (纸本)9789811581540

Intelligent aircraft control is an important strategic development trend. Traditional aircraft control algorithms have a strong dependence on the system models, and it is difficult to cope with the increasingly complex battlefield environment for intelligent aircrafts. In this paper, an online intelligent controller design based on a weak-model reinforcement learning technology is proposed to solve stabilization problem of an aircraft. The control problem is firstly converted to an optimal control problem, then an adaptive dynamic programming (ADP) technology is applied for computing the corresponding nonlinear Hamilton-Jacobi-Bellman equation (HJB) equation. Then, actor-critic neural networks structures are established to learn the optimal controller online where only partial information of the aircraft dynamics is required. The proposed control strategy enables the aircraft to adjust and update its control strategy on-line according to the actual mission targets and environments, such that the requirements of autonomous learning and intelligent operation can be realized. Finally, simulation example is offered to validate the effectiveness of the proposed weak-model based controller design. © 2022, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Reinforcement learning

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A Multi-Modal Multi-Objective Evolutionary Algorithm Based on Dual Decomposition and Subset Selection

SSRN

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SSRN 2023年

作者： Xiong, Minghui Xiong, Wei Liu, Zheng Liu, Yali Han, Chi Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing101416 China

Multi-modal multi-objective problems (MMOPs) arise frequently in real world applications, in which multiple Pareto-optimal solution sets (PSs) correspond to the same point on the Pareto front (PF). Diversity preservation is a crucial issue in multi-modal multi-objective evolutionary algorithms (MMEAs), which aims at evolving the population toward the PF and equivalent PSs with a uniform distribution and good spread. In spite of many diversity preservation approaches in MMEAs, most of them guarantee the diversity in decision space with a degraded performance in objective space. To address the above issues, this article proposes a MMEA based on dual decomposition and subset selection, which employes the weight vectors and grids to decompose both the objective and decision spaces. On the basis of dual decomposition, the mating selection are adaptively performed based on estimated optimization stages of current subproblem. Moreover, a subset with good diversity in both the objective and decision spaces are selected from the promising solutions ever collected during the evolution process. Experimental results on 22 benchmark problems demonstrate our advantages to maintain a more balanced diversity in both objective and decision spaces. © 2023, The Authors. All rights reserved.

关键词： Multiobjective optimization

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Design and optimization of dot pattern in illumination lightpipe of natural light guiding system

Design and optimization of dot pattern in illumination light...

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SPIE Optical Engineering + Applications

作者： Lee, Zong-Yi Chen, Yi-Yung Whang, Allen Jong-Woei Photonics System Simulation and Design Laboratory Department of Electronic Engineering National Taiwan University of Science and Technology Taipei 106 Taiwan Photonics System Simulation and Design Laboratory Department of Electro-Optical Engineering National Taiwan University of Science and Technology #43 Sec. 4 Keelung Rd. Taipei 106 Taiwan

ISBN: (纸本)9780819477194

In recent years, the practicality and importance of the illumination with sunlight are getting more seriously concern in public. The reason is that natural light is non-polluting, energy-saving, and healthy in comparison with traditional light sources. Therefore, our research focuses on how to replace the artificial sources by natural light. A Natural Light Guiding system has collecting, transmitting, and lighting parts. For replacing the traditional sources, the lighting part should have similar characteristic, such as intensity distribution and geometric parameters, to artificial sources. In this paper, we design, simulate, and optimize illumination lightpipe with dot pattern to redistribute the collecting sunlight from Natural Light Guiding system. The lightpipe includes input, system, and output parts. In the input part, we design a coupler to improve the coupling efficiency with natural light. For optimizing the efficiency of the coupler, we evaluate the relationship between the distance that is from the fiber to the lightpipe and the coupled power. In the system part, the sunlight is locked by total internal reflection, TIR, so we design dot pattern to scatter the locked sunlight for uniform lighting. In the output part, a uniform illumination is our goal. For designing the percentage of the surface will be covered by dot pattern, we offer a design theory and simulate the efficiency. © 2009 Copyright SPIE - The International Society for Optical Engineering.

关键词： Refractive index

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A beam splitter of natural light guiding system based on dichroic prism for ecological illumination

A beam splitter of natural light guiding system based on dic...

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SPIE Optical Engineering + Applications

作者： Li, Yu-Chi Chen, Yi-Yung Whang, Allen Jong-Woei Photonics System Simulation and Design Laboratory Department of Electro-Optical Engineering National Taiwan University of Science and Technology Taipei 106 Taiwan Photonics System Simulation and Design Laboratory Department of Electronic Engineering National Taiwan University of Science and Technology #43 Sec. 4 Keelung Rd. Taipei 106 Taiwan

ISBN: (纸本)9780819477194

In thremmatology, many researches focus on ecological illumination for improving the growing speed of animal or plant. According to the Trichromatic theory, any specific color can be made up of red, green, and blue light. Sunlight has full spectrum so it is the most applicable source. A Natural Light Guiding system includes collecting, transmitting, and lighting parts. In our research, we would like to design a beam splitter in the transmitting part to separate the sunlight into red, green, and blue light for ecological illumination. We use high pass and low pass dichroic coatings in a prism, called dichroic prism, to be the beam splitter to separate the wavelength. For measuring the spectra of the exit beams, we build a space with the Natural Light Guiding system. In the space, the spectra of sunlight outside and inside the space and the exit beams of the beam splitter are measured. Finally, we use prismatic structure to design the beam splitter, and optimize the surface of the element with aspheric surface and Fresnel surface to reduce the beam angle of exit light. © 2009 Copyright SPIE - The International Society for Optical Engineering.

关键词： Optical instruments

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An optical switch of natural light guiding system based on cubic structure with Fresnel surface

An optical switch of natural light guiding system based on c...

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SPIE Optical Engineering + Applications

作者： Chou, Kao-Hsu Chen, Yi-Yung Whang, Allen Jong-Woei Photonics System Simulation and Design Laboratory Department of Electronic Engineering National Taiwan University of Science and Technology Taipei 106 Taiwan Photonics System Simulation and Design Laboratory Department of Electro-Optical Engineering National Taiwan University of Science and Technology #43 Sec. 4 Keelung Rd. Taipei 106 Taiwan

ISBN: (纸本)9780819477187

Recently, many researches focus on illumination with sunlight for saving energy and healthy lighting. A Natural Light Guiding system has collecting, transmitting, and lighting parts. In most systems, the paths on transmitting part are fixed so the collected sunlight of the Natural Light Guiding system can not be free managed and is sometime wasted. In this paper, we design an optical switch to change the path of the collected sunlight on the transmitting sunlight. The switch is cubic structure that includes a 45 degree mirror for reflecting sunlight. According to the structure of the optical switch, we can rotate the switch to manage the path of the collected sunlight. When the path is parallel with the mirror, the sunlight will pass through the switch;and when the included angle between the path and mirror is 45 degree, we can change the path of light. For coupling the exit beam into lightpipe, we design the surfaces of cubic structure to be aspheric surface with Fresnel surface. Finally, we simulate the efficiency of the optical switch when the path is changed by the mirror. © 2009 Copyright SPIE - The International Society for Optical Engineering.

关键词： Lighting

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Design method of secondary optical element for LED applications

Design method of secondary optical element for LED applicati...

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SPIE Optical Engineering + Applications

作者： Chen, Yi-Yung Whang, Allen Jong-Woei Photonics System Simulation and Design Laboratory Department of Electronic Engineering National Taiwan University of Science and Technology Taipei 106 Taiwan Photonics System Simulation and Design Laboratory Department of Electro-Optical Engineering National Taiwan University of Science and Technology #43 Sec. 4 Keelung Rd. Taipei 106 Taiwan

ISBN: (纸本)9780819477187

Light Emitting Diode, LED, has many advantages in many lighting applications, such as general illumination, street light, and auto lamp. In general, each application needs to do secondary optical design for its specific request. A secondary optical element can be separated into refractive and reflective part. In this paper, we present a design procedure of secondary optical design with intensity distribution of LED and sequential ray tracing. The method suits the both designs of refractive and reflective parts. In the first process, we integrate the series function of intensity distribution in spherical coordinate with a range of solid angle. In the second process, we calculate the redistribution parameters of luminous flux by the geometric parameters of LED, element, and detector. In the final process, we use ray tracing method to design the optical element by aspheric surface. The surface of the refractive part in secondary optical element could be Fresnel surface for reducing the thickness of element. For proving the design procedure, we design a secondary optical element of LED by this method with an illumination request. © 2009 Copyright SPIE - The International Society for Optical Engineering.

关键词： Light emitting diodes

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Application of the jury test in stability analysis of an explicit fourth-order staggered FDTD method

Application of the jury test in stability analysis of an exp...

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2008 Asia Pacific Microwave Conference, APMC 2008

作者： Fei, Xiao Guohong, Du Xiaohong, Tanga National Key Laboratory of High-Frequency Complex System School of Electronic Engineering University of Electronic Science and Technology of China ChengduSichuan China School of Electronic Engineering Chengdu University of Information Technology Chengdu China

ISBN: (纸本)9781424426423

At present,the research on high-order accurate finite-difference time-domain (FDTD) method for the solution of Maxwell's equations is very *** example,an explicit fourth-order staggered FDTD method is proposed ***,to find out all roots of high-order characteristic polynomial equation for stability analysis is a very difficult *** this paper,the Jury test in automatic control theory is introduced,which only use those coefficients of the characteristic polynomial equation for stability analysis instead of directly solving *** treatment can greatly simplify the procedure of stability analysis. ©2008 IEEE.

关键词： Finite difference time domain method

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An Architectural Approach for Capability Mapping and Gap Analysis

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Journal of systems science and Information 2013年第1期1卷 86-96页

作者： Kewei YANG Bingfeng GE Qingsong ZHAO Jiang JIANG Science and Technology on Complex Systems Simulation Laboratory National University of Defense Technology College of Information System and Management

To cope with the increasing complexity and constantly changing capability requirements of system-of-systems, an architectural approach for capability mapping and gap analysis is ***, a more specific architecture framework is presented. Secondly, on the basis of the analysis of the semantic relationships between constituent architecture data elements, a capability mapping approach is proposed to manage the relations between capabilities and systems based on the mapping matrixes representing associations of core entities. Then, a four-step capability mapping process for the mapping from capabilities to systems is suggested. Moreover, the capability gap analysis on how to identify and fill the capability gaps is also studied. Finally, an example of specific Net-Centric Warfare mission of Precision Engagement is used to illustrate the feasibility of the approach.

关键词： system-of-systems capability architecture description mapping matrixes core entities gap analysis

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An active lighting module with natural light guiding system and solid state source for indoor illumination

An active lighting module with natural light guiding system ...

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9th International Conference on Solid State Lighting

作者： Chen, Chi-An Chen, Yi-Yung Whang, Allen Jong-Woei Photonics System Simulation and Design Laboratory Department of Electro-Optical Engineering National Taiwan University of Science and Technology #43 Keelung Rd. Taipei 106 Taiwan Photonics System Simulation and Design Laboratory Department of Electronic Engineering National Taiwan University of Science and Technology #43 Keelung Rd. Taipei 106 Taiwan

ISBN: (纸本)9780819477125

Recently, many researches focus on healthy lighting with sunlight. A Natural Light Guiding system includes collecting, transmitting, and lighting parts. In general, the lighting module of the Natural Light Guiding system only uses scattering element, such as diffuser, to achieve uniform illumination. With the passive lighting module, the application of the Natural Light Guiding system is limited because sunlight is dynamic source. When the sunlight is weak at morning, at evening, or on cloudy day, the illumination system is fail. In this paper, we provide an active lighting module that includes the lighting part of Natural Light Guiding system, LED auxiliary sources, optical elements, and optical detector. We use optical simulation tool to design and simulate the efficiency of the active module. The optical element can redistribute the sunlight only, LED light only, or sunlight with LED light to achieve uniform illumination. With the feedback of the detector, the active lighting module will adjust the intensity of LED to provide a steady illumination. Moreover, the module could replace the backlight module of LCD TV when the house has Natural Light Guiding system for saving energy and higher performance of image. © 2009 SPIE.

关键词： Light emitting diodes

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