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A new sampler for simulating aerosol deposition in the respiratory tract

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Nuclear Science and Techniques 2008年第3期19卷 169-173页

作者： LI Dehong ZHUO Weihai YI Yanling CHEN Bo liu haikuan Institute of Radiation Medicine Fudan University Shanghai 200032 China

For estimation of the deposition fractions of radon progeny in different regions of the respiratory tract, a new sampler consisting of three different configurations of sampling heads was developed. The deposition fractions of aerosols on the wire screens inside the sampling heads were calculated with the fan model of filtration theory. The deposition fractions of aerosols in different regions of the respiratory tract were calculated with the lung dose evaluation program (LUDEP)developed by National Radiological Protection Board (NRPB) as references. In general indoor and mine environments, the deviation between the deposition fractions of attached aerosol on the wire screens designed in this study and its reference values in the respiratory tract is less than 5%. It is possible to accurately estimate the deposition fractions of radon progeny in different regions of the respiratory tract through mimic measurements of radon progeny collected with the new sampler.

关键词：放射性污染环境放射学气溶胶呼吸过程

Robust adaptive output stabilization using dynamic normalizing signal

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控制理论与应用（英文版） 2007年第1期5卷 89-93页

作者： Haixia SU Xuejun XIE haikuan liu School of Electrical Engineering ＆ Automation Xuzhou Normal University Xuzhou Jiangsu 221116 China Institute of Automation Qufu Normal University Qufu Shandong 273165 China

For a class of nonlinear systems with dynamic uncertainties, robust adaptive stabilization problem is considered in this paper. Firstly, by introducing an observer, an augmented system is obtained. Based on the system, we construct an exp-ISpS Lyapunov function for the unmodeled dynamics, prove that the unmodeled dynamics is exp-ISpS, and then obtain a dynamic normalizing signal to counteract the dynamic disturbances. By the backstepping technique, an adaptive controller is given, it is proved that all the signals in the adaptive control system are globally uniformly ultimately bounded, and the output can be regulated to the origin with any prescribed accuracy. A simulation example further demonstrates the efficiency of the control scheme.

关键词： Unmodeled dynamics Exp-ISpS Dynamic normalizing signal Backstepping Adaptive control

Surface Acidity of Aluminum Phosphate and Its Catalytic Performance in Benzene Alkylation with Long Chain Olefin

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Chinese Journal of Chemical Engineering 2013年第6期21卷 627-632页

作者： YUAN haikuan liu Xuru REN Jie SHEN Lian College of Chemical Engineering and Materials Science Zhejiang University Of Technology Hangzhou 310032 China

The acidic properties of aluminum phosphate （A1PO4-5） solid acid catalyst were characterized by tem- perature programmed desorption （TPD） of ammonia （NH3）, n-propylamine （n-C3HTNH2）, iso-propylamine [（CH3）2CHNH2] and n-dipropylamine [（C3H7）2NH] separately, and its catalytic performance in benzene alkylation with long chain olefin was studied in a fixed-bed reactor. The characterized acid amount of catalyst increased with the basicity of adsorbates. With increase of the activation temperature of catalyst, the acid amount characterized by NHa-TPD decreased, however, it increased when characterized by TPD using three other adsorbates. The desorption kinetics of TPD process and the deactivation kinetics of catalyst were investigated. The acidity and catalytic per- formance of catalyst was also correlated. The results showed that the acid amount and strength are well correlated with the activity and stability using NH3 as adsorbate, respectively, which indicated NH3 was a better basic adsorbate. It was also found that the catalyst with higher acid amount and lower acid strength on the surface exhibited the better catalytic performance and stability.

关键词： suuface acidity temperature'programmed desorption basic adsorbate benzene alkylation catalytic activity

Construction of a computational MDCT model for simulations of the detector signals

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Radiation Medicine and Protection 2023年第1期4卷 48-53页

作者： Chuyan Wang Xin Lin Hongming liu Jianwei Fu Weihai Zhuo haikuan liu Institute of Radiation Medicine Fudan UniversityShanghai 200032China Shanghai United Imaging Healthcare Co. LtdShanghai 201816China

Objective:To develop a computational model of a multi-detector CT scanner(MDCT),which could be used to simulate the signal of each detector element in the MDCT by using the Monte Carlo ***:The CT scanner was modelled,including the X-ray source,the bowtie filter,the collimator,the couch and the detector *** a general scanning condition,the signal in each detector element was simulated based on the model by using the MCNPX *** the energy spectra at different tube voltages and energy deposition in the detector panel at different collimations were simulated to test the robustness of the MDCT model built in this ***,the simulated signals in each detector element were compared with their recorded *** accuracies were evaluated by the relative root mean square error(RRMSE)and the structural similarity(SSIM)for each detector element and the whole detector panel,***:The simulated energy spectra before and after passing through the phantom and simulated energy deposition in the detector panel were *** the scan range from the apex of lung to pubic symphysis,the RRMSE of the 18 axial projections ranged from 0.02 to 0.17,with an average of *** the SSIMs were calculated to be 0.979 and 0.976 for projections with the largest peak signal and the smallest peak signal,***:The computational model of the MDCT developed in this study is accurate and successful,it is helpful for further accurate simulations of the radiation dose and image quality of the MDCT.

关键词： CT scanner Computational model Monte Carlo simulation Detector signal

3D Model Feature Extraction Method Based on the Partial Physical Descriptor

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3D Model Feature Extraction Method Based on the Partial Phys...

Comparison of three models for winter wheat yield prediction based on UAV hyperspectral images

2013年中国智能自动化学术会议

作者： Kuansheng Zou haikuan liu Zengqiang Chen Jianhua Zhang School of Electrical Engineering and Automation Jiangsu Normal University College of Information Technical Science Nankai University

With the rapid development of 3D scanners,graphic accelerated hardware and modeling tools,the application of 3D model databases is growing in both numbers and *** is a pressing need for effective content-based 3D model retrieval *** this paper,a novel 3D model retrieval system called Physical Descriptor(PDD) is *** physical descriptor is defined as the physical features extracted from the 3D ***,after pose normalization for 3D database,the 3D model is partitioned into several parts by the planes paralleling the XOY,YOZ and XOZ plane *** partial part is represented by a physical feature named as PPD,which is a combination the inertia moment,elastic potential energy and the density of the sliced *** retrieval performance measures demonstrate that the proposed approach is superior to other methods.

关键词： 3D model retrieval Partial physical descriptor Continuous principal component analysis Feature extraction

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 260-267页

作者： Xiaobin Xu Cong Teng Hongchun Zhu haikuan Feng Yu Zhao Zhenhai Li College of Geodesy and Geomatics Shandong University of Science and TechnologyQingdao 266590ShandongChina Key Laboratory of Quantitative Remote Sensing in Ministry of Agriculture and Rural Affairs Information Technology Research CenterBeijing Academy of Agriculture and Forestry SciencesBeijing 100097China

Predicting crop yield timely can considerably accelerate agricultural production management and food policy-making,which are also important requirements for precise agricultural *** the development of hyperspectral imaging technology,a simple and efficient modeling method is convenient for predicting crop yield by using airborne hyperspectral *** this study,the Unmanned Aerial Vehicle(UAV)hyperspectral and maturity yield data in 2014-2015 and 2017-2018 were *** winter wheat yield prediction model was established by optimizing Vegetation Indices(VIs)feature scales and sample scales,incorporating Partial Least Squares Regression(PLSR),Random Forest algorithm(RF),and Back Propagation Neural Network algorithm(BPN).Results showed that PLSR stands out as the optimal wheat yield prediction model considering stability and accuracy(RMSE=948.88 kg/hm2).Contrary to the belief that more input features result in higher accuracy,PLSR,RF,and BPN models performed best when trained with the top 3,8,and 4 VIs with the highest correlation,*** an increase in training samples,model accuracy improves,reaching stability when the training samples reach *** PLSR and optimal feature scales,UAV yield prediction maps were generated,holding significant value for field management in precision agriculture.

关键词： hyperspectral imagery unmanned aerial vehicle winter wheat yield prediction model remote sensing

大功率场合高性能的级联多电平变频调速系统的研究

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计算机测量与控制 2010年第5期18卷 1164-1167页

作者：刘丽俊刘海宽徐州师范大学电气学院江苏徐州221116

级联多电平变频调速技术是高压大功率场合广泛应用的一种技术;为了实现调速系统的高性能控制,提出矢量控制和三角载波移相PWM方法相结合的控制策略;阐述了级联多电平矢量控制系统的系统构成、基本原理、级联五电平主电路拓扑结构及其载... 详细信息

级联多电平变频调速技术是高压大功率场合广泛应用的一种技术;为了实现调速系统的高性能控制,提出矢量控制和三角载波移相PWM方法相结合的控制策略;阐述了级联多电平矢量控制系统的系统构成、基本原理、级联五电平主电路拓扑结构及其载波移相PWM控制技术;基于MATLAB/Simulink Blocks工具箱的系统仿真结果表明级联多电平逆变器可以成倍提高等效载波频率,降低输出谐波含量,还验证了所提方案的可行性,系统能够获得良好的调速性能。

关键词：级联多电平调速矢量控制载波移相PWM控制

A new Chinese standard for testing of quality control in medical proton/heavy ion beam radiotherapy equipment

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Radiation Medicine and Protection 2023年第4期4卷 177-181页

作者： Jilong Yuan Xiangjie Ma Quanfu Sun haikuan liu Shouping Xu Yinxiangzi Sheng Xiaoyun Ma Xiangkui Mu Xinguo liu Tao Yang Xin Zhang Hsiao-Ming Lu Jinsheng Cheng Key Laboratory of Radiological Protection and Nuclear Emergency China CDCNational Institute for Radiological ProtectionChinese Center for Disease Control and PreventionWHO Collaboration Center for Radiation and HealthBeijing 100088China Institute of Radiation Medicine Fudan UniversityShanghai 200032China National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Medical Physics Shanghai Proton and Heavy Ion Center Shanghai Engineering Research Center of Proton and Heavy Ion Radiation TherapyShanghai 201315China Heavy Ion Center of Wuwei Cancer Hospital Gansu Wuwei Academy of Medical SciencesGansu Wuwei Tumor HospitalWuwei 733000China Department of Radiation Oncology Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical SciencesJinan 250117China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Department of Radiation Oncology The First Medical Center of Chinese PLA General HospitalBeijing 100853China Varian Medical Systems China Co. LtdBeijing 100176China Hefei Ion Medical Center Hefei230088China Ion Medical Research Institute University of Science and Technology of ChinaHefei 230088China

With the development of social economy and radiotherapy technique,proton/heavy ion radiotherapy has been applied widely to clinical *** present,there are at least 29 hospitals in China at various stages of planning,construction,commissioning or clinical operation of medical proton/heavy ion beam radiotherapy *** with common radiotherapy accelerators used in conventional external beam radiotherapy,the proton/heavy ion therapy system has more stringent requirements for quality control so as to achieve an optimum therapeutic *** order to protect the health rights of patients undergoing radiotherapy,to facilitate the relevant administrative supervision departments to carry out standard-based approval and routine supervision and to promote the development of related medical undertakings,the standard for testing of quality control for medical proton/heavy ion beam radiotherapy equipment is drafted to fill the gap in this regard in China and even *** standard contains five indicators and corresponding testing methods for radiological protection and safety and 16 indicators for quality control of equipment *** standard is a mandatory standard and is based on the relevant Chinese legal requirements for the testing of radiotherapy equipment,so all the indicators listed in the standard shall be *** the drafting of the standard,the opinions from hospitals that are currently using proton/heavy ion medical accelerators for radiotherapy purpose and from the related equipment manufacturers were taken into *** draft standard was revised with reference to these opinions and the feasibility of the related quality control *** official version of the standard was released on March 7,2023,and implementation is scheduled to begin on March 1,2024.

关键词： Chinese standard Proton Heavy ion Radiotherapy Quality control

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能量泛函正则化模型在图像恢复中的应用分析

中国图象图形学报 2014年第9期19卷 1247-1259页

作者：李旭超刘海宽宋博江苏师范大学电气工程及自动化学院徐州221116

目的能量泛函正则化模型是图像恢复研究的热点。为使更多工程领域的研究者对正则化技术进行探索和应用,推动不适定问题的研究,对能量泛函正则化模型的进展进行了分析。方法首先建立图像整体坐标与局部坐标的关系,分析图像恢复正则化模... 详细信息

目的能量泛函正则化模型是图像恢复研究的热点。为使更多工程领域的研究者对正则化技术进行探索和应用,推动不适定问题的研究,对能量泛函正则化模型的进展进行了分析。方法首先建立图像整体坐标与局部坐标的关系,分析图像恢复正则化模型的基本原理,给出并证明正则化模型各向同性与各向异性扩散定理。然后结合函数空间、图像分解和紧框架,评述能量泛函正则化模型国内外发展现状,并对正则化模型解的适定性进行分析。结果推导出图像恢复正则化模型扩散基本原理,给出正则化模型通用表达式,讨论正则化模型存在的问题及未来的发展方向。结论正则化技术在解决图像恢复、修复等反问题起着重要作用。目前,国内外学者对该问题的研究取得了一些成果,但许多理论问题有待进一步研究。

关键词：图像恢复正则化模型偏微分方程能量泛函