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Emission of intermediate volatility organic compounds from a ship main Engine burning heavy fuel oil

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Journal of Environmental Sciences 2019年第10期31卷 197-204页

作者： Haijun Lou Yuejiao Hao Weiwei Zhang Penghao Su Fan Zhang Yingjun Chen Daolun Feng Yifan Li College of Merchant Marine Shanghai Maritime University Shanghai 201306 China Department of Environmental Engineering Shanghai Maritime University Shanghai 201306 China College of Environmental Science and Engineering Tongji University Shanghai 200092 China International Joint Research Center for Persistent Toxic Substances(IJRC-PTS) Shanghai Maritime University Shanghai 200135 China International Joint Research Center for Persistent Toxic Substances(IJRC-PTS-NA) Toronto Ontario M2N 6X9 Canada

Intermediate volatility organic compounds(IVOCs)are crucial precursors of secondary organic aerosol(SOA).In this study,gaseous IVOCs emitted from a ship main Engine burning heavy fuel oil(HFO)were investigated on a test bench,which could simulate the real-world operations and emissions of ocean-going ships.The chemical compositions,emission factors(EFs)and volatility distributions of IVOC emissions were investigated.The results showed that the main Engine burning HFO emitted a large amount of IVOCs,with average IVOC EFs of 20.2-201 mg/kg-fuel.The IVOCs were mainly comprised of unspeciated compounds.The chemical compositions of exhaust IVOCs were different from that of HFO fuel,especially for polycyclic aromatic compounds and alkylcyclohexanes.The volatility distributions of IVOCs were also different between HFO exhausts and HFO fuel.The distinctions in IVOC emission characteristics between HFO exhausts and HFO fuel should be considered when assessing the IVOC emission and related SOA formation potentials from ocean-going ships burning HFO,especially when using fuel-surrogate models.

关键词： Marine main Engine Intermediate-volatility organic compounds Heavy fuel oil Emission factor Chemical composition Distribution

Raman spectroscopy of diesel and gasoline Engine-out soot using different laser power

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Journal of Environmental Sciences 2019年第5期31卷 74-80页

作者： Haiwen Ge Zhipeng Ye Rui He Department of Mechanical Engineering Texas Tech University Department of Electrical and Computer Engineering Texas Tech University

We studied Engine-out soot samples collected from a heavy-duty direct-injection diesel Engine and port-fuel injection gasoline spark-ignition Engine. The two types of soot samples were characterized using Raman spectroscopy with different laser powers. A Matlab program using least-square-method with trust-region-reflective algorithm was developed for curve fitting. A DOE(design of experiments) method was used to avoid local convergence. The method was used for two-band fitting and three-band fitting. The fitting results were used to determine the intensity ratio of D(for "Defect" or "Disorder") and G(for"Graphite") Raman bands. It is found that high laser power may cause oxidation of soot sample, which gives higher D/G intensity ratio. Diesel soot has consistently higher amorphous/graphitic carbon ratio, and thus higher oxidation reactivity, compared to gasoline soot, which is reflected by the higher D/G intensity ratio in Raman spectra measured under the same laser power.

关键词： Raman spectroscopy Diesel Engine Gasoline Engine Soot emission Particulate matter

基于Google Earth Engine的环渤海地区土地覆盖分类

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应用生态学报 2020年第12期31卷 4091-4098页

作者：于莉莉孙立双张丹华刘淼谢志伟平晓莹沈阳建筑大学交通工程学院沈阳110117 中国科学院沈阳应用生态研究所中国科学院森林生态与管理重点实验室沈阳110016

环渤海地区由于城市和经济发展,导致土地覆盖快速变化,对其进行高精度实时的变化监测是相关研究的重要基础。传统单机处理模式难以进行大尺度和长时间序列的快速监测,而整合海量数据的遥感大数据云计算平台的出现使其成为可能。本研究基... 详细信息

环渤海地区由于城市和经济发展,导致土地覆盖快速变化,对其进行高精度实时的变化监测是相关研究的重要基础。传统单机处理模式难以进行大尺度和长时间序列的快速监测,而整合海量数据的遥感大数据云计算平台的出现使其成为可能。本研究基于Google Earth Engine(GEE)处理平台,采用决策树(CART)方法对研究区2000—2019年土地覆盖进行解译分类,并综合分析研究区土地覆盖变化及对比不同数据源解译结果。结果表明:基于GEE平台能够实现大区域快速土地覆盖分类,对沿海湿地和其他覆盖类型具有较高的分类精度,与实测点对比达到80%以上。相较于Landsat影像,基于Sentinel-2A影像的解译结果在精度上有较大的提高,总体分类精度从85%提高到95%,地表更多细节信息得到体现。2000年,研究区湿地、建设用地、耕地、林地和水体的面积分别为1612.5、5734.9、32074.8、11853、3504.3 km2,分别占总面积的2.9%、10.5%、58.6%、21.6%、6.4%。到2019年,湿地减少了775.1 km2,下降40.1%;建设用地增加5310.5 km2,增加了92.6%;耕地、林地和水体分别下降了1841.6、1823.5、870.3 km2,分别下降5.7%、24.8%、48.1%。说明沿海的城市化过程导致建设用地占用其他类型,是研究区土地覆盖变化的最主要驱动力。

关键词： Google earth Engine Sentinel-2A影像土地覆盖湿地提取 CART分类

Model reference adaptive control with smooth switching scheme for piecewise linear systems and its application in turbofan Engine control

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航空动力学报 2019年第7期34卷 1615-1623页

作者： SUN Penghui WANG Xi YANG Bei ZENG Detang School of Energy and Power Engineering Beijing University of Aeronautics and AstronauticsBeijing100191China School of Aircraft Engineering Nanchang Hangkong UniversityNanchang330063China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China

A model reference adaptive control(MRAC)with smooth switching scheme was proposed for piecewise linear systems,and the method was utilized in turbofan Engine control to avoid the discontinuity of control input.In this scheme,each sub-region of the operating envelope had its own MRAC controller,and smooth indicator function based smooth switching scheme was introduced to switch multiple controllers smoothly at the boundary of adjacent sub-regions.The Lyapunov stability analysis indicated that the proposed smooth switching scheme can guarantee the convergence of the closed-loop system during the controllers switching.The tracking error system was converted into a switched system to analyze the global stability of the closed-loop system.The advantage of the method was that the chattering of system output and instability caused by asynchronous switching can be eliminated.The simulation illustrates the effectiveness of the proposed control scheme in comparison with the existing MRAC controller with gain scheduling for turbofan Engine.

关键词： model reference adaptive control turbofan Engine smooth switching Lyapunov function dwell time Lyapunov stability

基于GEE的山东省近30年农业大棚时空动态变化研究

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农业机械学报 2020年第1期51卷 168-175页

作者：朱德海刘逸铭冯权泷欧聪郭浩刘建涛中国农业大学土地科学与技术学院北京100083 自然资源部农用地质量与监控重点实验室北京100193 中国农业大学资源与环境学院北京100193 山东建筑大学测绘地理信息学院济南250101

针对精确获取大尺度空间范围内农业大棚的分布情况并进行长时间的序列动态监测存在数据量大、计算效率低、精度不高等问题,利用Google Earth Engine(GEE)云平台能够实现快速存取、实时处理海量卫星数据,基于多时相Landsat影像进行农业... 详细信息

针对精确获取大尺度空间范围内农业大棚的分布情况并进行长时间的序列动态监测存在数据量大、计算效率低、精度不高等问题,利用Google Earth Engine(GEE)云平台能够实现快速存取、实时处理海量卫星数据,基于多时相Landsat影像进行农业大棚时序光谱特征和纹理特征的自动提取,采用随机森林算法实现山东省农业大棚的遥感分类,从而生成了山东省近30年农业大棚的空间分布和时空动态变化图。结果表明,本文分类流程具有较高的分类精度,其平均总体精度达到91.63%,Kappa系数均值为0.8642。经分析,山东省农业大棚从1990年的6.67 km^2增加到2018年的9919.40 km^2,增长速度为354.03 km^2/a。

关键词：农业大棚时空变化 Google Earth Engine 大尺度范围随机森林 Landsat

Advancements in compressed air Engine technology and power system integration: A comprehensive review

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Energy Reviews

Energy Reviews 2023年第4期2卷 49-62页

作者： Haifei Tian Hualiang Zhang Zhao Yin Yu Liu Xinjing Zhang Yujie Xu Haisheng Chen Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China Nanjing Institute of Future Energy System Institute of Engineering ThermophysicsChinese Academy of SciencesNanjing211135China University of Chinese Academy of Sciences Beijing100049China

The compressed air power system demonstrates the ability to convert the internal energy stored within com-pressed air into mechanical energy,thus facilitating power output.Its application within specific domains,such as special purpose vehicles,standby power sources,and fire and explosion prevention,holds significant research and practical value owing to its combustion-free operation,zero pollution and emissions.This paper aims to explain the operational principles and unique features of the compressed air Engine(CAE).The reasons for selecting volume-type expanders as CAE components are detailed,including an analysis of their technical characteristics and research developments.Building on this foundation,the paper explores the operational characteristics and research status of traditional compressed air power systems installed in vehicles,with a particular focus on their limited range and excessive cold temperature.Furthermore,the study presents a comprehensive summary of the research progress made in the last few years relating to hybrid power systems that derive from conventional compressed air power systems.Finally,the paper concludes by outlining the expected development trajectory of CAEs and compressed air power systems.

关键词： Compressed air Engine Hybrid Power system Vehicle

Augmented flight dynamics model for pilot workload evaluation in tilt-rotor aircraft optimal landing procedure after one Engine failure

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Chinese Journal of Aeronautics 2019年第1期32卷 92-103页

作者： Xufei YAN Renliang CHEN National Key Laboratory of Science and Technology on Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics

An augmented flight dynamics model is developed to extend the existing flight dynamics model of tilt-rotor aircraft for optimal landing procedure analysis in the event of one Engine failure.Compared with the existing flight dynamics model, the augmented model involves with more pilot control information in cockpit and is validated against the flight test data. Based on the augmented flight dynamics model, the optimal landing procedure of XV-15 tilt-rotor aircraft after one Engine failure is formulated into a Nonlinear Optimal Control Problem(NOCP), solved by collocation and numerical optimization method. The time histories of pilot controls in cockpit during the optimal landing procedure are obtained for the evaluation of pilot workload. An evaluation method which can synthetically quantify the pilot workload in time and frequency domains is proposed with metrics of aggressiveness and cutoff frequencies of pilot controls. The scale of the pilot workload is compared with those of the shipboard landing procedures, bob-up/bob-down and dash/quickstop maneuvers of UH-60 helicopter. The results show that the aggressiveness of pilot collective and longitudinal controls for the tilt-rotor aircraft optimal landing procedure after one Engine failure are higher than those for UH-60 helicopter shipboard landing procedures up to the condition of sea state 4, while the pilot cutoff frequency of collective control is lower than that of the bob-up/bob-down maneuver but the pilot cutoff frequency of longitudinal control is higher than that of the dash/quick-stop maneuver. The evaluated pilot workload level is between Cooper–Harper HQR Level 2 and Level 3.

关键词： Landing procedure One Engine failure Optimal control problem Pilot workload Tilt-rotor aircraft

Conceptual design of automobile Engine rubber mounting composite using TRIZ-Morphological chart-analytic network process technique

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Defence Technology（防务技术） 2018年第4期14卷 268-277页

作者： A.M.Noor Azammi S.M.Sapuan M.R.Ishak Mohamed T.H.Sultan Department of Mechanical and Manufacturing Engineering University Putra Malaysia43400SerdangSelangorMalaysia Automotive Engineering Technology Section UniKL-MFI43650B.B.BangiSelangorMalaysia Laboratory of Biocomposite Technology Institute of Tropical Forestry and Forest Products(INTROP)Universiti Putra Malaysia43400UPM SerdangSelangorMalaysia Department of Aerospace Engineering Universiti Putra Malaysia43400UPM SerdangSelangorMalaysia

An Engine rubber mounting is one of the important parts of a vehicle. It is a function to isolate or absorb and to reduce vibration to the vehicle body thus to the passenger itself. Due to the Engine compartments environment such as heat and massive vibration due to road conditions, the Engine rubber mountings lifespan has been reduced. Thus several studies have been conducted to upgrade the material lifespan to make it more reliable and better Engine mounting components. This paper presents the conceptual design of kenaf fiber polymer as automotive Engine rubber mounting composites using the integration of Theory of Inventive Problem Solving(TRIZ). In this early stage, the solution is generated using 40 inventive principles and TRIZ contradiction method. The solution parameter for the specific design character is the selected using the morphological chart to develop a systematic conceptual design for the component. Four(4) innovative design concepts were produced and Analytic Network Process(ANP)methods were utilized to perform the multi-criteria decision-making process of selecting the best concept design for the polymer composite Engine rubber mounting component.

关键词： TRIZ ANP Morphological Automotive composites component Engine rubber composite mounting

Aircraft Engine fault detection based on grouped convolutional denoising autoencoders

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Chinese Journal of Aeronautics 2019年第2期32卷 296-307页

作者： Xuyun FU Hui LUO Shisheng ZHONG Lin LIN Department of Mechanical Engineering Harbin Institute of Technology at Weihai School of Mechatronics Engineering Harbin Institute of Technology

Many existing aircraft Engine fault detection methods are highly dependent on performance deviation data that are provided by the original equipment manufacturer. To improve the independent Engine fault detection ability, Aircraft Communications Addressing and Reporting System(ACARS) data can be used. However, owing to the characteristics of high dimension, complex correlations between parameters, and large noise content, it is difficult for existing methods to detect faults effectively by using ACARS data. To solve this problem, a novel Engine fault detection method based on original ACARS data is proposed. First, inspired by computer vision methods, all variables were divided into separated groups according to their correlations. Then, an improved convolutional denoising autoencoder was used to extract the features of each group. Finally, all of the extracted features were fused to form feature vectors. Thereby, fault samples could be identified based on these feature vectors. Experiments were conducted to validate the effectiveness and efficiency of our method and other competing methods by considering real ACARS data as the data source. The results reveal the good performance of our method with regard to comprehensive fault detection and robustness. Additionally, the computational and time costs of our method are shown to be relatively low.

关键词： Aircraft Engines Anomaly detection Convolutional Neural Network(CNN) Denoising autoencoder Engine health management Fault detection