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Chinese Journal of Aeronautics 2020年第1期33卷 339-351页

作者： Ali RAHDAN Hossein BOLANDI Mostafa ABEDI Department of Electrical Engineering Iran University of Science&TechnologyTehran ***Iran Department of Electrical Engineering Shahid Beheshti UniversityTehran ***Iran

Digital sun sensor is one of the most important sensors used in the Attitude Determination System(ADS)of the satellite.Due to the harsh environmental conditions that exist in the space,various distortions may occur in the sun sensor optical system that lead to the reduced accuracy of this equipment.So,it is necessary to recalibrate the optical parameters of the aforementioned sensors.For this purpose,first a novel attitude independent error model is proposed for the SS-411 sun sensor that includes the central point of the CCD array,installation error,filter thickness and sensor misalignment.So,the mutual interfaces between the sensor parameters are considered in the developed model.In order to extract the sensor parameters,a nonlinear optimization technique called the Levenberg–Marquardt is applied to the developed model as a batch algorithm.In addition,the Extended Kalman Filter(EKF)and the Unscented Kalman Filter(UKF)have been utilized as sequential strategies.It will be shown that by considering a worst case of variation amount for sensor parameters,an accuracy improvement of about 17°is achieved by the developed calibration algorithms.Comparison between the developed algorithms represents that UKF has higher accuracy,shorter time convergence but higher computational load.

关键词： Digital sun sensor Extended Kalman filter Levenberg–Marquardt on-board calibration Unscented Kalman filter

Real-world fuel consumption of light-duty passenger vehicles using on-board diagnostic (OBD) systems

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Frontiers of Environmental Science & Engineering 2020年第2期14卷 207-216页

作者： Xuan Zheng Sheng Lu Liuhanzi Yang Min Yan Guangyi Xu Xiaomeng Wu Lixin Fu Ye Wu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China School of Environment State Key Joint Laboratory of Environment Simulation and Pollution ControlTsinghua UniversityBeijing 100084China International Council on Clean Transportation Beijing 100084China Shenzhen Research Academy of Environmental Sciences Shenzhen 518001China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China

An increasing discrepancy between real-world and type-approval fuel consumption for light-duty passenger vehicles(LDPVs)has been reported by several studies.Normally,real-world fuel consumption is measured primarily by a portable emission measurement system.The on-board diagnostic(OBD)approach,which is flexible and offers high-resolution data collection,is a promising fuel consumption monitoring method.Three LDPVs were tested with a laboratory dynamometer based on a type-approval cycle,the New European Driving Cycle(NEDC).Fuel consumption was measured by the OBD and constant-volume sampling system(CVS,a regulatory method)to verify the accuracy of the OBD values.The results of the OBD method and the regulatory carbon balance method exhibited a strong linear correlation(e.g.,R^2=0.906-0.977).Compared with the carbon balance results,the fuel consumption results using the OBD were 7.1%±4.3%lower on average.Furthermore,the real-world fuel consumption of six LDPVs was tested in Beijing using the OBD.The results showed that the normalized NEDC real-world fliel consumption of the tested vehicles was 13%±17%higher than the type-approval-based fuel consumption.Because the OBD values are lower than the actual fuel consumption,using a carbon balance method may result in a larger discrepancy between real-word and type-approval ftiel consumption.By means of the operating mode binning and micro trip methods,a strong relationship(R^2=0.984)was established between the average speed and relative fuel consumption.For congested roads(average vehicle speed less than 25 km/h),the fuel consumption of LDPVs is highly sensitive to changes in average speed.

关键词： Fuel consumption Light-duty passenger vehicles on-board diagnostic systems

Partial Iterative Decode of Turbo Codes for on-board Processing Satellite Platform

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China Communications 2015年第11期12卷 104-111页

作者： LI Hang GAO Zhen ZHAO Ming WANG Jing Department of Electronic Engineering Tsinghua University School of Electronic Information Engineering Tianjin University

There is a contradiction between high processing complexity and limited processing resources when turbo codes are used on the on-board processing(OBP)satellite platform.To solve this problem,this paper proposes a partial iterative decode method for on-board application,in which satellite only carries out limited number of iteration according to the on-board processing resource limitation and the throughput capacity requirements.In this method,the soft information of parity bits,which is not obtained individually in conventional turbo decoder,is encoded and forwarded along with those of information bits.To save downlink transmit power,the soft information is limited and normalized before forwarding.The iteration number and limiter parameters are optimized with the help of EXIT chart and numerical analysis,respectively.Simulation results show that the proposed method can effectively decrease the complexity of onboard processing while achieve most of the decoding gain..

关键词： satellite communication on-board processing partial iterative decoding

Stream-computing of High Accuracy on-board Real-time Cloud Detection for High Resolution Optical Satellite Imagery

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Journal of Geodesy and Geoinformation Science 2019年第2期2卷 50-59页

作者： Mi WANG Zhiqi ZHANG Zhipeng DONG Shuying JIN Hongbo SU State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China Collaborative Innovation Center of Geospatial Technology Wuhan 430079 China Department of Civil Environmental and Geomatics Engineering Florida Atlantic University 33431 USA

This paper focuses on the time efficiency for machine vision and intelligent photogrammetry, especially high accuracy on-board real-time cloud detection method. With the development of technology, the data acquisition ability is growing continuously and the volume of raw data is increasing explosively. Meanwhile, because of the higher requirement of data accuracy, the computation load is also becoming heavier. This situation makes time efficiency extremely important. Moreover, the cloud cover rate of optical satellite imagery is up to approximately 50%, which is seriously restricting the applications of on-board intelligent photogrammetry services. To meet the on-board cloud detection requirements and offer valid input data to subsequent processing, this paper presents a stream-computing of high accuracy on-board real-time cloud detection solution which follows the “bottom-up” understanding strategy of machine vision and uses multiple embedded GPU with significant potential to be applied on-board. Without external memory, the data parallel pipeline system based on multiple processing modules of this solution could afford the “stream-in, processing, stream-out” real-time stream computing. In experiments, images of GF-2 satellite are used to validate the accuracy and performance of this approach, and the experimental results show that this solution could not only bring up cloud detection accuracy, but also match the on-board real-time processing requirements.

关键词： machine vision intelligent photogrammetry cloud detection stream computing on-board real-time processing

Comparing of Hydrogen on-board Storage by the Largest Car Companies, Relevance to Prospects for More Efficient Technologies

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Open Journal of Energy Efficiency 2017年第3期6卷 73-79页

作者： Yu. S. Nechaev V. G. Makotchenko M. B. Shavelkina M. Yu. Nechaev A. Veziroglu T. N. Veziroglu I. P. Bardin Central Research Institute for Ferrous Metallurgy Dpt. G. V. Kurdyumov Institute of Metals Science and Physics Moscow Russia A. V. Nikolaev Institute of Inorganic Chemistry The Siberian Branch of the Russian Academy of Sciences Novosibirsk Russia The Joint Institute for High Temperature The Russian Academy of Sciences Moscow Russia International Association for Hydrogen Energy Miami FL USA

It presented a comparative consideration of General Motors long-term activities on the current subject of fuel-cell-powered electric vehicles vs Toyota Mirai recent results, relevant to prospects on more efficient and safe technologies of the hydrogen on-board storage. It also presented a call on the project International cooperation. The main aim of this paper is to attract attention of General Motors, Toyota and/or other large car companies to a real possibility of developing and using, in the nearest future, of the break-through hydrogen on-board storage technology based on the solid H2 intercalation into graphite nanostructures.

关键词： GM’ Activities vs Toyota Mirairesults Prospects on Developing of a Break-Through Hydrogen on-board Storage Technology The Solid H2 Intercalation into Graphite Nanostructures Call on the Project International Cooperation

Thermodynamic Aspects of the Graphene/Graphane/Hydrogen Systems: Relevance to the Hydrogen on-board Storage Problem

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Advances in Materials Physics and Chemistry 2013年第5期3卷 255-280页

作者： Yury S. Nechaev T. Nejat Veziroglu Bardin Institute for Ferrous Metallurgy Kurdjumov Institute of Metals Science and Physics Vtoraya Baumanskaya St. Moscow Russia International Association for Hydrogen Energy Miami USA

The present analytical review is devoted to the current problem of thermodynamic stability and related thermodynamic characteristics of the following graphene layers systems: 1) double-side hydrogenated graphene of composition CH (theoretical graphane) (Sofo et al. 2007) and experimental graphane (Elias et al. 2009);2) theoretical single-side hydrogenated graphene of composition CH;3) theoretical single-side hydrogenated graphene of composition C2H (graphone);4) experimental hydrogenated epitaxial graphene, bilayer graphene and a few layers of graphene on SiO2 or other substrates;5) experimental and theoretical single-external side hydrogenated single-walled carbon nanotubes, and experimental hydrofullerene C60H36;6) experimental single-internal side hydrogenated (up to C2H or CH composition) graphene nanoblisters with intercalated high pressure H2 gas inside them, formed on a surface of highly oriented pyrolytic graphite or epitaxial graphene under the atomic hydrogen treatment;and 7) experimental hydrogenated graphite nanofibers-multigraphene with intercalated solid H2 nano-regions of high density inside them, relevant to solving the problem of hydrogen on-board storage (Nechaev 2011-2012).

关键词： Hydrogenated Graphene Layers Graphanes Thermodynamic Stability Solid Hydrogen Intercalated into Hydrogenated Graphite Nanofibers Hydrogen on-board Storage

Statistical Model for Estimating Carbon Dioxide Emissions from a Light-Duty Gasoline Vehicle

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Journal of Environmental Protection 2013年第8期4卷 8-15页

作者： Benjamin Afotey Melanie Sattler Stephen P. Mattingly Victoria C. P. Chen Department of Chemical Engineering Kwame Nkrumah University of Science and Technology Kumasi Ghana Department of Civil Engineering The University of Texas at Arlington Arlington USA Department of Industrial and Manufacturing Systems Engineering The University of Texas at Arlington Arlington USA

The objective of this research was development of a statistical model for estimating vehicle tailpipe emissions of carbon dioxide (CO2). Forty hours of second-by-second emissions data (144,000 data points) were collected using an on-board emissions measurement System (Horiba OBS-1300) installed in a 2007 Dodge Charger car. Data were collected for two roadway types, arterial and highway, around Arlington, Texas, and two different time periods, off peak and peak (both a.m. and p.m.). Multiple linear regression and SAS software were used to build emission models from the data, using predictor variables of velocity, acceleration and an interaction term. The arterial model explained 61% of the variability in the emissions;the highway model explained 27%. The arterial model in particular represents a reasonably good compromise between accuracy and ease of use. The arterial model could be coupled with velocity and acceleration profiles obtained from a micro-scale traffic simulation model, such as CORSIM, or from field data from an instrumented vehicle, to estimate percent emission reductions associated with local changes in traffic system operation or management.

关键词： Carbon Dioxide Model on-board Emissions Measurement System Mobile Sources