检索结果-南通市图书馆

New probabilistic transformation of imprecise belief structure

Journal of Systems Engineering and Electronics 2011年第5期22卷 721-729页

作者： Lifang Hu You He Xin Guan Deqiang han yong Deng Research Institute of Information Fusion Naval Aeronautical and Astronautical University Yantai 264001 E R. China Navy Armament Academy Beijing 102249 E R. China College of Electronic Science and Engineering National University of Defense Technology Changsha 410073 E R. China Institute of Integrated Automation Xi＇an Jiaotong University Xi＇an 710049 E R. China School of Electronics and Information Technology Shanghai Jiaotong University Shanghai 200240 E R. China

The case when the source of information provides precise belief function/mass, within the generalized power space, has been studied by many people. However, in many decision situations, the precise belief structure is not always available. In this case, an interval-valued belief degree rather than a precise one may be provided. So, the probabilistic transformation of imprecise belief function/mass in the generalized power space including Dezert-Smarandache （DSm） model from scalar transformation to sub-unitary interval transformation and, more generally, to any set of sub-unitary interval transformation is provided. Different from the existing probabilistic transformation algorithms that redistribute an ignorance mass to the singletons involved in that ignorance pro- portionally with respect to the precise belief function or probability function of singleton, the new algorithm provides an optimization idea to transform any type of imprecise belief assignment which may be represented by the union of several sub-unitary （half-） open intervals, （half-） closed intervals and/or sets of points belonging to [0,1]. Numerical examples are provided to illustrate the detailed implementation process of the new probabilistic transformation approach as well as its validity and wide applicability.

关键词： pignistic probability transformation generalized power space interval value information fusion uncertainty.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Sources of nitrous and nitric oxides in paddy soils: Nitrification and denitrification

引用

Journal of Environmental Sciences 2014年第3期26卷 581-592页

作者： Ting Lan yong han Marco Roelcke Rolf Nieder Zucong Cai State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Institute of Geoecology Technische Universitt Braunschweig School of Geography Sciences Nanjing Normal University

Rice-paddies are regarded as one of the main agricultural sources of N 2O and NO emissions. To date, however, specific N2O and NO production pathways are poorly understood in paddy soils. ^15N-tracing experiments were carded out to investigate the processes responsible for N2O and NO production in two paddy soils with substantially different soil properties. Laboratory incubation experiments were carried out under aerobic conditions at moisture contents corresponding to 60% of water holding capacity. The relative importance of nitrification and denitrification to the flux of NaO was quantified by periodically measuring and comparing the enrichments of the N2O, NH^-N and NO3-N pools. The results showed that both N2O and NO emission rates in an alkaline paddy soil with clayey texture were substantially higher than those in a neutral paddy soil with silty loamy texture. In accordance with most published results, the ammonium N pool was the main source of N2O emission across the soil profiles of the two paddy soils, being responsible for 59.7% to 97.7% of total N2O emissions. The NO3-N pool of N2O emission was relatively less important under the given aerobic conditions. The rates of N2O emission from nitrification （N2On） among different soil layers were significantly different, which could be attributed to both the differences in gross N nitrification rates and to the ratios of nitrified N emitted as NzO among soil layers. Furthermore, NO fluxes were positively correlated with the changes in gross nitrification rates and the ratios of NO/N2O in the two paddy soils were always greater than one （from 1.26 to 6.47）. We therefore deduce that, similar to N2O, nitrification was also the dominant source of NO in the tested paddy soils at water contents below 60% water holding capacity.

关键词： ^15N tracing model N2O NO NO/N2O nitrification denitrification

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Broken Rotor Bar Fault Detection of Induction Motors Using a Joint Algorithm of Trust Region and Modified Bare-bones Particle Swarm Optimization

引用

Chinese Journal of Mechanical Engineering 2019年第1期32卷 65-78页

作者： Panpan Wang Liping Shi yong Zhang Yifan Wang Li han School of Electrical and Power Engineering China University of Mining & Technology

A precise detection of the fault feature parameter of motor current is a new research hotspot in the broken rotor bar(BRB) fault diagnosis of induction motors. Discrete Fourier transform(DFT) is the most popular technique in this field, owing to low computation and easy realization. However, its accuracy is often limited by the data window length, spectral leakage, fence e ect, etc. Therefore, a new detection method based on a global optimization algorithm is proposed. First, a BRB fault current model and a residual error function are designed to transform the fault parameter detection problem into a nonlinear least-square problem. Because this optimization problem has a great number of local optima and needs to be resolved rapidly and accurately, a joint algorithm(called TR-MBPSO) based on a modified bare-bones particle swarm optimization(BPSO) and trust region(TR) is subsequently proposed. In the TR-MBPSO, a reinitialization strategy of inactive particle is introduced to the BPSO to enhance the swarm diversity and global search ability. Meanwhile, the TR is combined with the modified BPSO to improve convergence speed and accuracy. It also includes a global convergence analysis, whose result proves that the TR-MBPSO can converge to the global optimum with the probability of 1. Both simulations and experiments are conducted, and the results indicate that the proposed detection method not only has high accuracy of parameter estimation with short-time data window, e.g., the magnitude and frequency precision of the fault-related components reaches 10^(-4), but also overcomes the impacts of spectral leakage and non-integer-period sampling. The proposed research provides a new BRB detection method, which has enough precision to extract the parameters of the fault feature components.

关键词： Fault detection Broken rotor bars Induction motors Bare-bones particle swarm optimization Trust region

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Identification of injury type using somatosensory and motor evoked potentials in a rat spinal cord injury model

引用

Neural Regeneration Research 2023年第2期18卷 422-427页

作者： Rong Li han-Lei Li Hong-Yan Cui yong-Can Huang yong Hu Department of Orthopedics and Traumatology The University of Hong Kong-Shenzhen HospitalShenzhenGuangdong ProvinveChina Department of Neurosurgery Neuroscience CenterIntegrated Hospital of Traditional Chinese MedicineSouthern Medical UniversityGuangzhouGuangdong ProvinveChina Institute of Biomedical Engineering Chinese Academy of Medical Sciences and Peking Union Medical CollegeTianjinChina Shenzhen Engineering Laboratory of Orthopedic Regenerative Technologies Department of Spine SurgeryPeking University Shenzhen HospitalShenzhenGuangdong ProvinveChina Department of Orthopedics and Traumatology The University of Hong KongPokfulamHong Kong Special Administrative RegionChina

The spinal cord is at risk of injury during spinal *** intraoperative spinal co rd injury is identified early,irreve rsible impairment or loss of neurological function can be *** types of spinal cord injury result in damage to diffe rent spinal cord regions,which may cause diffe rent somatosensory and motor evoked potential signal res *** this study,we examined electrophysiological and histopathological changes between contusion,distra ction,and dislocation spinal cord injuries in a rat *** found that contusion led to the most severe dorsal white matter injury and caused considerable attenuation of both somatosensory and motor evoked *** resulted in loss of myelinated axons in the lateral region of the injured spinal cord along the rostrocaudal *** amplitude of attenuation in motor evoked potential responses caused by dislocation was greater than that caused by *** distraction injury,extracellular spaces were slightly but not significantly enlarged;somatosensory evoked potential res ponses slightly decreased and motor evoked potential responses were *** analysis showed that histological and electrophysiological findings we re significantly correlated and related to injury *** rative monitoring of both somatosensory and motor evoked potentials has the potential to identify iatrogenic spinal cord injury type during surgery.

关键词： contusion injury dislocation injury distraction injury electropnysiology heterogeneity histopathology injury mechanism motor evoked potential somatosensory evoked potential spinal cord injury

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Flexible manufacturing technology of controlling exact bake hardening value in continuous galvanizing line

引用

Journal of Iron and Steel Research International 2018年第12期25卷 1296-1302页

作者： Xiao-fei Zheng yong-lin Kang Bao-yong Wang Zhi-gang han Xin-Iong Luo School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Shougang Jingtang Iron and Steel United Co. Ltd. Tangshan 063200HebeiChina

Flexible manufacturing technology for ultra-low-carbon bake hardening (BH)steels with different solute carbon contents in the range of (6-16)× 10^-4 wt.%was systematically *** effects of soaking temperature,cooling rate and aging time on solute carbon content were *** bake hardening value in a continuous galvanizing line with an over-aging section was *** manufacturing parameters were calculated using the design of experiment to obtain the best and most flexible process *** indicate a relationship among carbon content,soaking temperature and cooling *** solute carbon is 9 × 10^-6,cooling rate is 50 ℃/s,the soaking temperature is 745 ℃,and BH value is 45 MPa,the requirements of an automobile factory can be met.

关键词： Bake hardening value Solute carbon content Aging time Soaking temperature Cooling rate

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Analysis on Collapse Strength of Casing Wear

引用

Chinese Journal of Mechanical Engineering 2013年第3期26卷 613-619页

作者： LIANG Erguo LI Zifeng han yong LI Guoqin GUO Peipei Tianjin Key Laboratory of High Speed Cutting and Precision Machining Tianjin University of Technology and Education College of Vehicles and Energy Yanshan University Xi'an Maurer Petroleum Engineering Laboratory Co. Ltd.

Carrying capacity of the casing will reduce after the casing is worn, which seriously affects the subsequent well drilling, well completion, oil extraction and well repair. A lot of researches on calculation of casing wear collapse strength have been done, but few of them focus on collapsing failure mechanism, and influencing factors and law of collapse strength. So, significant difference between estimated value and actual value of collapse strength comes into being. By theoretical analysis, numerical simulation and actual test, the collapsing failure mechanism of casing wear as well as the influencing factors and laws of collapse strength are investigated, and the investigation results show that collapse of crescent casing wear belongs to 'three hinged' instability. The severely-worn position on the casing is yielded into the plastic zone first then deformed greatly, which causes the plastic instability of the whole structure. The casing wear collapse strength presents changes of exponent, power function and linear trend with the residual casing wall thickness, wear radius and axial load, respectively. When the flexibility is less than 10°/30 m, the borehole bending has less impact on casing collapse strength. Thus, the computation model for the casing wear collapsing strength is established by introducing wear radius coefficient and casing equivalent yield strength, at the same time, the model is tested. The test results show that the relative error for the computation model is less than 5%. The research results provide a basis for design of the casing string strength and evaluation of down-hole safety.

关键词： casing wear collapsing failure collapse strength borehole bending computation model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Elastic direct envelope inversion based on wave mode decomposition for multi-parameter reconstruction of strong-scattering media

引用

Petroleum Science 2022年第5期19卷 2046-2063页

作者： Pan Zhang Ru-Shan Wu Li-Guo han yong Hu College of Geo-exploration Science and Technology Jilin UniversityChangchun 130026JilinChina Modeling and Imaging Laboratory Earth&Planetary ScienceUniversity of California at Santa CruzSanta CruzCalifornia95064USA School of Resources and Geosciences China University of Mining and TechnologyXuzhou 221008JiangsuChina

The parameter reconstruction of strong-scattering media is a challenge for conventional full waveform inversion(FWI).Direct envelope inversion(DEI)is an effective method for large-scale and strongscattering structures imaging without the need of low-frequency seismic ***,the current DEI methods are all based on the acoustic ***,in real cases,seismic records are the combined effects of the subsurface ***,the study of DEI in elastic media is necessary for the accurate inversion of strong-scattering structures,such as salt *** this paper,we propose an elastic direct envelope inversion(EDEI)method based on wave mode *** define the objective function of EDEI using multi-component seismic data and derive its gradient *** reduce the coupling effects of multi-parameters,we introduce the wave mode decomposition method into the gradient calculation of *** update of Vp is primarily the contributions of decomposed *** approaches on Vs gradient calculation are proposed,*** the petrophysical relation and wave mode decomposition ***,we test the proposed method on a layered salt model and the SEG/EAGE salt *** results show that the proposed EDEI method can reconstruct reliable large-scale Vp and Vs models of strong-scattering salt *** successive elastic FWI can obtain high-precision inversion results of the strong-scattering salt *** proposed method also has a good anti-noise performance in the moderate noise level.

关键词： Direct envelope inversion Full waveform inversion Elastic wave Strong-scattering media Multi-parameter

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

New conflict representation model in generalized power space

引用

Journal of Systems Engineering and Electronics 2012年第1期23卷 1-9页

作者： You He Lifang Hu Xin Guan Deqiang han yong Deng Research Institute of Information Fusion Naval Aeronautical and Astronautical University Yantai 264001 E R. China Navy Armament Academy Beijing 102249 P. R. China College of Electronic Science and Engineering National University of Defense Technology Changsha 410073 E R. China Institute of Integrated Automation Xi＇an Jiaotong University Xi＇an 710049 E R. China School of Electronics and Information Technology Shanghai Jiaotong University Shanghai 200240 E R. China

The study on alternative combination rules in Dempster- Shafer theory （DST） when evidences are in conflict has emerged again recently as an interesting topic, especially in data/information fusion applications. The earlier researches have mainly focused on investigating the alternative which would be appropriate for the conflicting situation, under the assumption that a conflict is identified. However, the current research shows that not only the combination rule but also the classical conflict coefficient in DST are not correct to determine the conflict degree between two pieces of evidences. Most existing methods of measuring conflict do not consider the open world situation, whose frame of discernment is incomplete. To solve this problem, a new conflict representa- tion model to determine the conflict degree between evidences is proposed in the generalized power space, which contains two parameters： the conflict distance and the conflict coefficient of inconsistent evidences. This paper argues that only when the con- flict measure value in the new representation model is high, it is safe to say the evidences are in conflict. Experiments illustrate the efficiency of the proposed conflict representation model.

关键词： Dezert-Smarandache theory (DSmT) conflict evidence Dempster rule of combination information fusion.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Progress in preparation of rare earth metals and alloys by electrodeposition in molten salts

引用

Rare Metals 2016年第11期35卷 811-825页

作者： Wei han Mei Li Mi-Lin Zhang yong-De Yan Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering University

Rare earth（RE） metals and their alloys have attracted considerable practical interests due to their functional properties. Because of their negative deposition potentials, RE metals cannot be electrochemically deposited from aqueous media. Using molten salt as medium provides a unique opportunity for the electrowinning and electrorefining of high-purity RE metals, as well as for the electrochemical formation of their alloys and intermetallic compounds. Certainly, the electrochemical behaviors of RE metals and their alloys have been investigated in a number of different molten salts comprising all-fiuorides,all-chlorides and mixed chloride-fiuoride media. Based on the results, RE and their alloys were produced by molten salt electrolysis. In this paper, the developments of preparation of RE metals and their alloys by electrolysis in molten salts in recent years were systematically summarized on both the local and international levels. Attention was paid mainly to the electrodeposition of RE metals and their alloys, including RE-Mg, RE-Al, RE-Ni, RE-Co,RE-Cu, RE-Fe and RE-Zn alloys.

关键词： Electrochemical formation Molten salts Electrolysis Rare earth Alloys

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Collection efficiency of a monitor parallel plate ionization chamber for pencil beam scanning proton therapy

引用

Nuclear Science and Techniques 2020年第2期31卷 1-10页

作者： Rong-Cheng han yong-Jiang Li Yue-Hu Pu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai APACTRON Particle Equipment Co.Ltd Shanghai 201800China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

The collection efficiency of monitor parallel plate ionization chambers is the main uncertainty in the beam control of pencil beam scanning *** calculation methods for collection efficiency in photon or passive scattering proton systems have not considered the characteristics of non-uniform charge density in pencil beam scanning *** this study,Boag’s theory was applied to a proton pencil beam scanning *** transverse distribution of charge density in the ionization chamber was considered to be a Gaussian function and an analytical solution was derived to calculate collection efficiency in the beam spot *** calculation method is called the integral method and it was used to investigate the effects of beam parameters on collection *** was determined that collection efficiency is positively correlated with applied voltage,beam size,and beam energy,but negatively correlated with beam current ***,it was confirmed that collection efficiency is improved when the air filling the monitor parallel plate ionization chamber is replaced with nitrogen.

关键词： Collection efficiency Monitor ionization chamber Pencil beam scanning Proton therapy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：