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成本法下多层混合持股的合并会计处理 被引量:1
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作者 张国永 刘子烨 《财务与会计》 北大核心 2019年第20期62-66,共5页
虽然合并财务报表的成本法具有简单、实用的特征,在实务中正在得到逐步的重视,但是对成本法的研究并不深入。本文正是在此情况下,对多层混合持股的成本法问题通过综合案例的形式进行了较深入的研究。研究发现,成本法解决多层混合持股的... 虽然合并财务报表的成本法具有简单、实用的特征,在实务中正在得到逐步的重视,但是对成本法的研究并不深入。本文正是在此情况下,对多层混合持股的成本法问题通过综合案例的形式进行了较深入的研究。研究发现,成本法解决多层混合持股的合并问题,关键是要计算出多层混合持股造成的多路径持股情况下各子公司直接和间接少数股东的持股份额,并在此基础上运用成本法编制合并财务报表。该方法与权益法相比大大简化了合并财务报表的编制。 展开更多
关键词 多层混合持 成本法 一次合并 少数股东权益
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Fabrication and Electromechanical Characteristics of 2×2 Torsion-Mirror Optical Switch Arrays with Monolithically Integrated Fiber Self-Holding Structures
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作者 吴文刚 郝一龙 +2 位作者 栗大超 张培玉 武国英 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第10期1024-1030,共7页
Novel 2×2 torsion-mirror optical switch arrays are fabricated by using the mixed micromachining based on the surface and bulk silicon microelectronics,then are investigated electromechanically in applied direct a... Novel 2×2 torsion-mirror optical switch arrays are fabricated by using the mixed micromachining based on the surface and bulk silicon microelectronics,then are investigated electromechanically in applied direct and alternating electric fields.When the thickness of the elastic torsion beams suspending the aluminum coated polysilicon micro-mirrors of the switches in the arrays is about 1μm,the electrostatic yielding voltages for driving the mirrors to achieve their ON-state are in the range of 270~290V,and the minimum holding voltages for mirrors ON-state are found as 55V or so.Theoretical analysis manifests that the yielding voltage is more sensitive to beam thickness than other design parameters do about the torsion-mirror switch structures.The lifetime can reach 10 8 times.The estimated shortest switching time of the switches at least lasts for less than 2ms.The force analysis on the two kinds of new fiber self-holding structures integrated monolithically in the chip of the optical switch arrays indicates that the structures can feature self-fixing and self-aligning of optical fibers. 展开更多
关键词 MEMS optical switch torsion-mirror fiber self-holding structures mixed micromachining
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Effects of Slow-Mixing on the Coagulation Performance of Polyaluminum Chloride (PACI) 被引量:3
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作者 张忠国 刘丹 +4 位作者 胡丹丹 李多 任晓晶 程言君 栾兆坤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第3期318-323,共6页
Conventional jar tests and on-line size monitoring were used to investigate the effects of slow-mixing intensity and duration on residual turbidity and floc size during charge neutralization coagulation and sweep floc... Conventional jar tests and on-line size monitoring were used to investigate the effects of slow-mixing intensity and duration on residual turbidity and floc size during charge neutralization coagulation and sweep floc- culation with polyaluminum chloride. The compensatory effect of slow-mixing on coagulation performance fol- low!ng inadequate_or excessive rapid-mi_xing was also examined. It is found that slowTmixing intensity has a more marked positive ettect on charge neutralization coas;ulatlon tlaan on sweep tlocculatlon. llle optimal root-mean- square velocity gradient, G, for slow-mixing is 15 s-' for both coagulation mechanisms, and charge neutralization coagulation requires a longer slow-mixing duration. The optimal slow-mixing duration, based on residual turbidity,is longer than the time to tbrm the largest mean Ilocs. The optimal product of G and mixing duration, GT, lbr slow-mixing during charge neutralization coagulation (13500) are higher than that during sweep flocculation (4500) and both are less than the range of values recommended by the American Water Works Association (24000-84000).The optimal GT value under various slow-mixing conditions increases with G. Appropriate extension'of slow-mixing duration during charge neutralization coagulation can improve coagulation performance after an inadequate or excessive rapid-mixing duration, but during sweep flocculation, appropriate shortening of slow-mixing duration after an excessive rapid-mixing or appropriate extension of slow-mixing duration after an inadequate rapid-mixing is favorable. 展开更多
关键词 slow-mixing polyaluminum chloride charge neutralization coagulation -sweep-flocculati-on GT value
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Ultra-High Strength Concrete Mixtures Using Local Materials 被引量:6
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作者 Srinivas Allena Craig M. Newtson 《Journal of Civil Engineering and Architecture》 2011年第4期322-330,共9页
This paper presents the development of ultra high strength concrete (UHSC) using local materials. UHSC mixture proportions were developed using local materials so that UHSC may be made more affordable to a wider var... This paper presents the development of ultra high strength concrete (UHSC) using local materials. UHSC mixture proportions were developed using local materials so that UHSC may be made more affordable to a wider variety of applications. Specifically, local sand with a top size of 600 um, and locally available Type I/II cement and silica fume were used in this research. Each of these material selections is seen as an improvement in sustainability for UHSC. Two mixtures (one with and one without fibers) were recommended as the UHSC mixtures. The greatest compressive strengths obtained in this study were 165.6 MPa for UHSC with steel fibers and 161.9 MPa for UHSC without fibers. The compressive and flexural strengths obtained from the UHSC mixtures developed in this work are comparable to UHSC strengths presented in the literature. Producing this innovative material with local materials reduces the cost of the material, improves sustainability, and produces mechanical performance similar to prepackaged, commercially available products. 展开更多
关键词 Compressive strength local materials modulus of rupture SUSTAINABILITY ultra-high strength
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Hybrid Support Vector Machines-Based Multi-fault Classification 被引量:11
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作者 GAO Guo-hua ZHANG Yong-zhong +1 位作者 ZHU Yu DUAN Guang-huang 《Journal of China University of Mining and Technology》 EI 2007年第2期246-250,共5页
Support Vector Machines (SVM) is a new general machine-learning tool based on structural risk minimization principle. This characteristic is very signific ant for the fault diagnostics when the number of fault sampl... Support Vector Machines (SVM) is a new general machine-learning tool based on structural risk minimization principle. This characteristic is very signific ant for the fault diagnostics when the number of fault samples is limited. Considering that SVM theory is originally designed for a two-class classification, a hybrid SVM scheme is proposed for multi-fault classification of rotating machinery in our paper. Two SVM strategies, 1-v-1 (one versus one) and 1-v-r (one versus rest), are respectively adopted at different classification levels. At the parallel classification level, using l-v-1 strategy, the fault features extracted by various signal analysis methods are transferred into the multiple parallel SVM and the local classification results are obtained. At the serial classification level, these local results values are fused by one serial SVM based on 1-v-r strategy. The hybrid SVM scheme introduced in our paper not only generalizes the performance of signal binary SVMs but improves the precision and reliability of the fault classification results. The actually testing results show the availability suitability of this new method. 展开更多
关键词 Suooort Vector Machines multi-fault classification hybrid strategy wavelet analysis
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Duration of treatment with 5-aminosalicylic acid compounds 被引量:1
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作者 T Moshkovska JF Mayberry 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第32期4310-4315,共6页
The development of 5-aminosalicylic acid (5-ASA) therapy as a life long treatment for ulcerative colitis is reviewed from its origins in the 1940s to the present day. The drug was designed to treat rheumatoid arthriti... The development of 5-aminosalicylic acid (5-ASA) therapy as a life long treatment for ulcerative colitis is reviewed from its origins in the 1940s to the present day. The drug was designed to treat rheumatoid arthritis,but was found helpful in the management of nine patients with ulcerative colitis. This discovery preceded the emergence of the clinical trial as a tool for assessing a new drug's efficacy; as a result it lacked scientific rigour and was selective in its presentation of results. Nevertheless it identified the future cornerstone of therapy in ulcerative colitis. In 1962,the first double blind controlled trial of sulphasalazine was conducted on 40 patients. Outcome measures were subjective and included symptoms and an assessment of the rectal mucosa. In 1973,the first two papers on the role of sulphasalazine in maintenance of remission were published. Both used placebo controls and had a stratified design. Outcomes were measured using "an intention to treat" approach. The British study of 64 patients used both subjective and objective criteria to assess outcomes. Patients on placebo had a relapse rate four times patients on active treatment and this founded the basis for a life long approach to therapy with 5-ASA compounds in ulcerative colitis. However,in 1985,a small "on demand" study of 32 patients suggested this approach might be as effective as continuous treatment. Some support for this view came from an Italian study which showed no benefit to continued treatment for those in remission for two years or more. The central problem these studies identify is that of adherence to treatment in the long-term. Few studies have considered patients' attitudes to continuous therapy and it is an area that needs further investigation. 展开更多
关键词 Ulcerative colitis 5-aminosalicylic acid compounds Sulphasalazine mesalazine adherance trials
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Novel hybrid FRP tubular columns for sustainable mining infrastructure:Recent research at University of Wollongong 被引量:1
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作者 Yu Tao Remennikov Alex M. 《International Journal of Mining Science and Technology》 SCIE EI 2014年第3期311-316,共6页
This paper introduces, for applications in the mining industry, an innovative hybrid column form which consists of an inner steel tube, an outer fibre-reinforced polymer(FRP) tube and an annular concrete infill betwee... This paper introduces, for applications in the mining industry, an innovative hybrid column form which consists of an inner steel tube, an outer fibre-reinforced polymer(FRP) tube and an annular concrete infill between them. The two tubes may be concentrically placed to produce a section form more suitable for columns, or eccentrically placed to produce a section form more suitable for beams. The FRP is combined with steel and concrete in these hybrid structural members in such a way that the advantages of FRP are appropriately exploited while its disadvantages are minimized. As a result, these hybrid members possess excellent corrosion resistance as well as excellent ductility and seismic resistance. This paper summarizes existing research on this new form of structural members, and discusses their potential applications in mining infrastructure before presenting a summary of the recent and current studies at University of Wollongong(UOW) on their structural behaviour and design. 展开更多
关键词 Hybrid column Tubular column Fibre reinforced polymer Sustainable mining infrastructure
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“混合所有”的股权结构提升了国有企业投资效率吗?——基于2008—2020中国上市公司的数据 被引量:5
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作者 夏秀芳 J.Daniel Chi 王京 《东岳论丛》 CSSCI 北大核心 2023年第2期99-110,192,共13页
混合所有制改革的首要动机是提高国有企业的资本效率,投资是企业重要的价值增值活动,国有企业混合所有制改革对公司绩效(ROA)的影响得到了学术界的广泛关注。有关混改对国有企业投资效率的影响,国内少量文献着重分析了混改对国企“非效... 混合所有制改革的首要动机是提高国有企业的资本效率,投资是企业重要的价值增值活动,国有企业混合所有制改革对公司绩效(ROA)的影响得到了学术界的广泛关注。有关混改对国有企业投资效率的影响,国内少量文献着重分析了混改对国企“非效率投资”(包括过度投资和投资不足)的影响,但国企混改所强调的“效率”更侧重的是投入产出比的概念,目前尚无基于这一视角的研究。本文首次从投入产出的视角分析了“混合所有”的股权结构对国有企业投资效率的影响,并从投入和产出的两个角度进行了混改影响投资效率的路径分析。实证分析结果表明:非国有股东持股比例与国有企业投资效率存在倒U型关系,前十大股东中非国有股份的持股比例约为20%时,“混合所有”的股权结构对国有企业投资效率的提升作用达到了最大。研究结论既支持了不同性质股权的资源协同和互补效应,同时也支持了制衡理论的权利纷争负效应。这一结论为混改优化国有企业股权结构、完善公司治理结构提供了重要的事实依据和政策启示。 展开更多
关键词 混合持 投资效率 资本成本 投资收益率 国有企业 混合所有制 股权结构
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Supervisory control of the hybrid off-highway vehicle for fuel economy improvement using predictive double Q-learning with backup models 被引量:1
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作者 SHUAI Bin LI Yan-fei +2 位作者 ZHOU Quan XU Hong-ming SHUAI Shi-jin 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第7期2266-2278,共13页
This paper studied a supervisory control system for a hybrid off-highway electric vehicle under the chargesustaining(CS)condition.A new predictive double Q-learning with backup models(PDQL)scheme is proposed to optimi... This paper studied a supervisory control system for a hybrid off-highway electric vehicle under the chargesustaining(CS)condition.A new predictive double Q-learning with backup models(PDQL)scheme is proposed to optimize the engine fuel in real-world driving and improve energy efficiency with a faster and more robust learning process.Unlike the existing“model-free”methods,which solely follow on-policy and off-policy to update knowledge bases(Q-tables),the PDQL is developed with the capability to merge both on-policy and off-policy learning by introducing a backup model(Q-table).Experimental evaluations are conducted based on software-in-the-loop(SiL)and hardware-in-the-loop(HiL)test platforms based on real-time modelling of the studied vehicle.Compared to the standard double Q-learning(SDQL),the PDQL only needs half of the learning iterations to achieve better energy efficiency than the SDQL at the end learning process.In the SiL under 35 rounds of learning,the results show that the PDQL can improve the vehicle energy efficiency by 1.75%higher than SDQL.By implementing the PDQL in HiL under four predefined real-world conditions,the PDQL can robustly save more than 5.03%energy than the SDQL scheme. 展开更多
关键词 supervisory charge-sustaining control hybrid electric vehicle reinforcement learning predictive double Q-learning
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Hybrid Features for an Arabic Word Recognition System
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作者 Mehmmood A. Abd Sarab Al Rubeaai George Paschos 《Computer Technology and Application》 2012年第10期685-691,共7页
This research proposes and implements an Arabic Sub-Words Recognition System (ASWR). The system focuses on employing a combination of statistical and structural features to provide complete pattern's description an... This research proposes and implements an Arabic Sub-Words Recognition System (ASWR). The system focuses on employing a combination of statistical and structural features to provide complete pattern's description and enhances the recognition rate. Support Vector Machines (SVMs) is utilized as a promising pattern recognition tool. In addition to that, the problems of dots and holes are solved in a completely different way from the ones previously employed. The proposed system proceeds in several phases as follows: (1) image acquisition, (2) binarisation, (3) morphological processing, (4) feature extraction, which includes statistical features, i.e., moment invariants, and structural features, i.e., dot number, dot position, and number of holes, features, and (5) classification, using multi-class SVMs and applying a one-against-all technique. The proposed system has been tested using different sets of words and subwords and has achieved a nearly 98.90% recogiaition rate. Comparative results with NNs are also presented. 展开更多
关键词 Arabic word recognition support vector machines CLASSIFICATION feature extraction neural networks morphological.
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Using Mixed Reality as a Simulation Tool in Urban Planning Project for Sustainable Development
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作者 Hisham E1-Shimy Ghada Ahmed Ragheb Amany Ahmed Ragheb 《Journal of Civil Engineering and Architecture》 2015年第7期830-835,共6页
Nowadays, urban design faces complex demands. It has become a necessity to negotiate between stakeholder objectives, the expectations of citizens and the demands of planning. It is desirable to involve the stakeholder... Nowadays, urban design faces complex demands. It has become a necessity to negotiate between stakeholder objectives, the expectations of citizens and the demands of planning. It is desirable to involve the stakeholders and citizens from an early stage in the planning process to enable their different viewpoints to be successfully expressed and comprehended. Therefore, the basic aim of the study was how the MR (mixed reality) application is designed to encourage and improve communication on urban design among stakeholders and citizens? In this paper, we discuss new approaches to visualize urban building and environment alternatives to different stakeholders and provide them with tools to explore different approaches to urban planning in order to support citizen's participation in urban planning with augmented and mixed reality. The major finding of the study is that learning "how these participatory technologies may help build a community of practice around an urban project". And throughout the different experiences, we can learn to assist towards development of a methodology to use the mixed reality as a simulation tool in the enhancement of collaborative interaction in real-Egyptian project. So, we can determine a number of recommendations to deal with new participatory design tools for urban planning projects. 展开更多
关键词 Mixed reality real environment virtual reality augmented reality augmented virtuality MR-tent.
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DEVELOPING EXPERT DECISION SUPPORT SYSTEM WTH VP-EXPERT AND LOTUS 1-2-3 IN RE-BLENDING BY USE
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作者 舒航 杨鹏 《Journal of China University of Mining and Technology》 1994年第2期104-111,共8页
An expert decision support system (EDSS) for multi-bins balance and contro1 of orequality in production ore bins of some large-scale open pit iron mine in China has been developed byexpert svitem tool software VP-EXPE... An expert decision support system (EDSS) for multi-bins balance and contro1 of orequality in production ore bins of some large-scale open pit iron mine in China has been developed byexpert svitem tool software VP-EXPERT and integration software LOTUS 1-2-3 in this paper. Itis known by practicing that a medium-scale EDSS constructed on microcomputer is completcly, feaasible by means of VP-EXEPERT to construct knowledge base system (KBS), LOTUS 1-2-3 tomake decision support system (DSS) and link them with BAT. 展开更多
关键词 VP-EXPERT LOTUS 1-2-3 ore-blending expert System decision support system expert decision support system
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Support vector machine with mixture of kernels for automatic image annotation
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作者 田东平 Zhao Xiaofei Shi Zhongzhi 《High Technology Letters》 EI CAS 2013年第3期295-300,共6页
Automatic image annotation(AIA)has become an important and challenging problem in computer vision due to the existence of semantic gap.In this paper,a novel support vector machine with mixture of kernels(SVM-MK)for au... Automatic image annotation(AIA)has become an important and challenging problem in computer vision due to the existence of semantic gap.In this paper,a novel support vector machine with mixture of kernels(SVM-MK)for automatic image annotation is proposed.On one hand,the combined global and local block-based image features are extracted in order to reflect the intrinsic content of images as complete as possible.On the other hand,SVM-MK is constructed to shoot for better annotating performance.Experimental results on Corel dataset show that the proposed image feature representation method as well as automatic image annotation classifier,SVM-MK,can achieve higher annotating accuracy than SVM with any single kernel and mi-SVM for semantic image annotation. 展开更多
关键词 automatic image annotation AIA) support vector machine SVM) kernel func-tion principal component analysis (PCA)
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Optimization of Resource in the Industry of Construction
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作者 Francisco Javier Gutierrez Garcia Pedro Perez Diaz Pedro Sanchez Luis 《Journal of Civil Engineering and Architecture》 2014年第9期1145-1150,共6页
Time and cost are two of the most important factors to consider in each construction project. In order to maximize performance, both the client and the contractor will work to optimize both the duration of the project... Time and cost are two of the most important factors to consider in each construction project. In order to maximize performance, both the client and the contractor will work to optimize both the duration of the project and its cost. We show a model of linear entire mixed programming to solve the considered problem. The aim is to minimize the project total time, by means of the assignment of equipments of work to the different production lines of the activities to realizing. The fundamental beginning is to support the same production (rate of production in meters/day of the activity in view of the equipment of work) for tbe different equipments to achieve the maximum efficiency in each period of time. With the limited availability of resources, the work must be continuous and the period of time between operations and final must be kept. However, this paper also presents the bibliographical study on methodologies of the optimization of construction processes in response to the two objectives: time and cost. This will consider the use of recta-heuristic techniques, such as population based algorithms. 展开更多
关键词 OPTIMIZATION construction process HEURISTICS mathematical programming.
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自动弹力线套扎术+外痔切除术治疗混合痔的临床疗效观察
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作者 顾红 马炯 +2 位作者 袁保 夏晶晶 季红英 《中文科技期刊数据库(全文版)医药卫生》 2022年第8期65-68,共4页
混合痔病在临床上是比较常见的一种肛周疾病,一般采用保守治疗,如塞药、外用熏洗、口服药物等多种保守治疗的方法,然后,临床上也有很多患者在保守治疗无效的情况下,只能选择进一步的手术切除治疗,本文章主要是探讨混合痔患者行保守治疗... 混合痔病在临床上是比较常见的一种肛周疾病,一般采用保守治疗,如塞药、外用熏洗、口服药物等多种保守治疗的方法,然后,临床上也有很多患者在保守治疗无效的情况下,只能选择进一步的手术切除治疗,本文章主要是探讨混合痔患者行保守治疗无效后,选择下一步的手术治疗。主要是观察混合痔的手术患者在使用自动弹力线套扎技术+外痔切除技术在治疗混合痔患者的临床预后观察。方法 选择符合纳入标准的240例患者,按照自愿随意的患者随机分为实验组和对照组,手术治疗组采用自动弹力线套扎术加外痔切除术,对照组采用传统手术技术之混合痔的外痔剥除内痔结扎术,对两组患者在我科治疗后的的总体的有效率、术后患者在第1、3、5、7天的创面疼痛、术后患者尿潴留等方面进行对比分析,对两种手术方式的安全及术后的整体疗效做评估。结果 实验组自动弹力线套扎技术加外痔切除术及混合痔外剥内扎术的手术治疗过程中都没有出现严重不良事件; 术后第3、7、30d伤口疼痛情况进行比较,弹力线组与外痔剥除内痔结扎术差异有统计学意义,术后创面恢复时间及术后肛门术后的坠胀感情况较对照组有统计学意义。结论 自动弹力线套扎术加外痔切除术来治疗混合痔的手术方式,与传统的混合痔的外痔剥除内痔结扎术接近,术后患者创面的疼痛较轻,创面愈合时间相对而言比较短,尿潴留的术后发生的机率比较低,更好的维护了肛口精细功能,具有很好的安全性和比较好的临床疗效。 展开更多
关键词 自动弹力线 外剥内扎术 混合持 临床研究 疼痛 愈合时间
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Application of complete ensemble intrinsic time-scale decomposition and least-square SVM optimized using hybrid DE and PSO to fault diagnosis of diesel engines 被引量:7
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作者 Jun-hong ZHANG Yu LIU 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第2期272-286,共15页
Targeting the mode-mixing problem of intrinsic time-scale decomposition (ITD) and the parameter optimization problem of least-square support vector machine (LSSVM), we propose a novel approach based on complete en... Targeting the mode-mixing problem of intrinsic time-scale decomposition (ITD) and the parameter optimization problem of least-square support vector machine (LSSVM), we propose a novel approach based on complete ensemble intrinsic time-scale decomposition (CEITD) and LSSVM optimized by the hybrid differential evolution and particle swarm optimization (HDEPSO) algorithm for the identification of the fault in a diesel engine. The approach consists mainly of three stages. First, to solve the mode-mixing problem of ITD, a novel CEITD method is proposed. Then the CEITD method is used to decompose the nonstationary vibration signal into a set of stationary proper rotation components (PRCs) and a residual signal. Second, three typical types of time-frequency features, namely singular values, PRCs energy and energy entropy, and AR model parameters, are extracted from the first several PRCs and used as the fault feature vectors. Finally, a HDEPSO algorithm is proposed for the parameter optimization of LSSVM, and the fault diagnosis results can be obtained by inputting the fault feature vectors into the HDEPSO-LSSVM classifier. Simulation and experimental results demonstrate that the proposed fault diagnosis approach can overcome the mode-mixing problem of ITD and accurately identify the fault patterns of diesel engines. 展开更多
关键词 Diesel Fault diagnosis Complete ensemble intrinsic time-scale decomposition (CE1TD) l east square supportvector machine (LSSVM) Hybrid differential evolution and particle swarm optimization (HDEPSO)
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Hybrid planning for LEO long-duration multi-spacecraft rendezvous mission 被引量:9
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作者 ZHANG Jin LUO YaZhong TANG GuoJin 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第1期233-243,共11页
For the low-earth-orbit (LEO) long-duration multi-spacecraft rendezvous mission, a mixed integer nonlinear programming (MINLP) model is built with consideration of the , perturbation and the time window constraint... For the low-earth-orbit (LEO) long-duration multi-spacecraft rendezvous mission, a mixed integer nonlinear programming (MINLP) model is built with consideration of the , perturbation and the time window constraints based on lighting condition. A two-level hybrid optimization approach is proposed. The up-level problem uses the visiting sequence, the orbital transfer duration and the service time after each rendezvous as design variables, and employs the mix-coded genetic algorithm to search the optimal solution; the low-level problem uses the maneuver time and impulses in each rendezvous as design vari- ables, and employs the downhill simplex method to search the optimal solution. To improve the solving efficiency of the low-level problem, a linear dynamic model with J~ perturbation is derived, and the approximate strategy of the low-level prob- lem is then proposed. The proposed method has been applied to several numerical problems. The results lead to three major conclusions: (1) The MINLP model for LEO long-duration multi-spacecraft rendezvous mission is effective, and the proposed hybrid optimization strategy can obtain good solutions that satisfy time window constraints; (2) The derived linear dynamic equations are good first-order approximation to the long-duration rendezvous trajectory under ,J2 perturbation; (3) Under J2 perturbation, the long-duration rendezvous problem has multiple local minimums either in the duration of multiple orbits or in a single orbit, and it agrees with the problem's characteristic to use the mix-coded genetic algorithm. 展开更多
关键词 multi-spacecraft rendezvous long-duration rendezvous hybrid planning rendezvous time window lighting constraints J2 perturbation
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