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The Impact of Model Based Offset Scaling Technique on the Amplitude Variation with Offset Responses from 3D Seismic Data Acquired from the Tano Basin, Offshore Ghana
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作者 Striggner Bedu-Addo Sylvester Kojo Danuor Aboagye Menyeh 《International Journal of Geosciences》 CAS 2024年第1期40-53,共14页
Amplitudes have been found to be a function of incident angle and offset. Hence data required to test for amplitude variation with angle or offset needs to have its amplitudes for all offsets preserved and not stacked... Amplitudes have been found to be a function of incident angle and offset. Hence data required to test for amplitude variation with angle or offset needs to have its amplitudes for all offsets preserved and not stacked. Amplitude Variation with Offset (AVO)/Amplitude Variation with Angle (AVA) is necessary to account for information in the offset/angle parameter (mode converted S-wave and P-wave velocities). Since amplitudes are a function of the converted S- and P-waves, it is important to investigate the dependence of amplitudes on the elastic (P- and S-waves) parameters from the seismic data. By modelling these effects for different reservoir fluids via fluid substitution, various AVO geobody classes present along the well and in the entire seismic cube can be observed. AVO analysis was performed on one test well (Well_1) and 3D pre-stack angle gathers from the Tano Basin. The analysis involves creating a synthetic model to infer the effect of offset scaling techniques on amplitude responses in the Tano basin as compared to the effect of unscaled seismic data. The spectral balance process was performed to match the amplitude spectra of all angle stacks to that of the mid (26°) stack on the test lines. The process had an effect primarily on the far (34° - 40°) stacks. The frequency content of these stacks slightly increased to match that of the near and mid stacks. In offset scaling process, the root mean square (RMS) amplitude comparison between the synthetic and seismic suggests that the amplitude of the far traces should be reduced relative to the nears by up to 16%. However, the exact scaler values depend on the time window considered. This suggests that the amplitude scaling with offset delivered from seismic processing is only approximately correct and needs to be checked with well synthetics and adjusted accordingly prior to use for AVO studies. The AVO attribute volumes generated were better at resolving anomalies on spectrally balanced and offset scaled data than data delivered from conventional processing. A typical class II AVO anomaly is seen along the test well from the cross-plot analysis and AVO attribute cube which indicates an oil filled reservoir. 展开更多
关键词 Amplitude Variation with Offset (AVO) model based Offset Scaling Technique Tano Basin
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Auxiliary Model Based Multi-innovation Stochastic Gradient Identification Methods for Hammerstein Output-Error System
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作者 冯启亮 贾立 李峰 《Journal of Donghua University(English Edition)》 EI CAS 2017年第1期53-59,共7页
Special input signals identification method based on the auxiliary model based multi-innovation stochastic gradient algorithm for Hammerstein output-error system was proposed.The special input signals were used to rea... Special input signals identification method based on the auxiliary model based multi-innovation stochastic gradient algorithm for Hammerstein output-error system was proposed.The special input signals were used to realize the identification and separation of the Hammerstein model.As a result,the identification of the dynamic linear part can be separated from the static nonlinear elements without any redundant adjustable parameters.The auxiliary model based multi-innovation stochastic gradient algorithm was applied to identifying the serial link parameters of the Hammerstein model.The auxiliary model based multi-innovation stochastic gradient algorithm can avoid the influence of noise and improve the identification accuracy by changing the innovation length.The simulation results show the efficiency of the proposed method. 展开更多
关键词 Hammerstein output-error system special input signals auxiliary model based multi-innovation stochastic gradient algorithm innovation length
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3DV quality model based depth maps for view synthesis in FTV system
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作者 张秋闻 安平 +2 位作者 张艳 张兆杨 王元庆 《Journal of Shanghai University(English Edition)》 CAS 2011年第4期335-341,共7页
Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems. When depth maps are derived using existing depth estimation methods, the depth distortions will cause undesirable artifacts ... Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems. When depth maps are derived using existing depth estimation methods, the depth distortions will cause undesirable artifacts in the synthesized views. To solve this problem, a 3D video quality model base depth maps (D-3DV) for virtual view synthesis and depth map coding in the FTV applications is proposed. First, the relationships between distortions in coded depth map and rendered view are derived. Then, a precisely 3DV quality model based depth characteristics is develop for the synthesized virtual views. Finally, based on D-3DV model, a multilateral filtering is applied as a pre-processed filter to reduce rendering artifacts. The experimental results evaluated by objective and subjective methods indicate that the proposed D-3DV model can reduce bit-rate of depth coding and achieve better rendering quality. 展开更多
关键词 free-viewpoint television (FTV) 3D video quality model base depth maps (D-3DV) view synthesis
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A Photonuclear Reaction Model Based on IQMD in Intermediate-Energy Region
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作者 黄勃松 马余刚 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期51-55,共5页
A photonuclear reaction transport model based on an isospin-dependent quantum molecular dynamics model (IQMD) is presented in the intermediate energy region, which is named as GiQMD in this study. Methodology to sim... A photonuclear reaction transport model based on an isospin-dependent quantum molecular dynamics model (IQMD) is presented in the intermediate energy region, which is named as GiQMD in this study. Methodology to simulate the course of the photonuclear reaction within the IQMD frame is described to study the photo- absorption cross section and π meson production, and the simulation results are compared with some available experimental data as well as the Giessen Boltzmann-Uehling-Uhlenbeck model. 展开更多
关键词 QMD A Photonuclear Reaction model based on IQMD in Intermediate-Energy Region
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A VISCOPLASTIC MODEL BASED ON NO-YIELD-SURFACE CONCEPT
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作者 周光泉 程经毅 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第4期337-344,共8页
The elasticjviscoplastic constitutive equation which describes deformation law of metal materials was suggested based on no-yield-surface concept and thermal activation theory of dislocation. The equation which takes ... The elasticjviscoplastic constitutive equation which describes deformation law of metal materials was suggested based on no-yield-surface concept and thermal activation theory of dislocation. The equation which takes account of effects of strain-rate, strain history, strain-rate history, hardening and temperature has stronger physical basis.Comparison of the theoretical prediction with experimental results of mechanical behaviours of Ti under conditions of uniaxial stress and room temperature shows good consistency. 展开更多
关键词 A VISCOPLASTIC model baseD ON NO-YIELD-SURFACE CONCEPT
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Reduced Model Based Control of Two Link Flexible Space Robot 被引量:11
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作者 Amit Kumar Pushparaj Mani Pathak Nagarajan Sukavanam 《Intelligent Control and Automation》 2011年第2期112-120,共9页
Model based control schemes use the inverse dynamics of the robot arm to produce the main torque component necessary for trajectory tracking. For model-based controller one is required to know the model parameters acc... Model based control schemes use the inverse dynamics of the robot arm to produce the main torque component necessary for trajectory tracking. For model-based controller one is required to know the model parameters accurately. This is a very difficult task especially if the manipulator is flexible. So a reduced model based controller has been developed, which requires only the information of space robot base velocity and link parameters. The flexible link is modeled as Euler Bernoulli beam. To simplify the analysis we have considered Jacobian of rigid manipulator. Bond graph modeling is used to model the dynamics of the system and to devise the control strategy. The scheme has been verified using simulation for two links flexible space manipulator. 展开更多
关键词 Flexible Space ROBOTS BOND GRAPH modeling REDUCED model based CONTROLLER Euler-Bernoulli Beam
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Application of the Improved Generalized Autoregressive Conditional Heteroskedast Model Based on the Autoregressive Integrated Moving Average Model in Data Analysis 被引量:2
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作者 Qi Yang Yishu Wang 《Open Journal of Statistics》 2019年第5期543-554,共12页
This study firstly improved the Generalized Autoregressive Conditional Heteroskedast model for the issue that financial product sales data have singular information when applying this model, and the improved outlier d... This study firstly improved the Generalized Autoregressive Conditional Heteroskedast model for the issue that financial product sales data have singular information when applying this model, and the improved outlier detection method was used to detect the location of outliers, which were processed by the iterative method. Secondly, in order to describe the peak and fat tail of the financial time series, as well as the leverage effect, this work used the skewed-t Asymmetric Power Autoregressive Conditional Heteroskedasticity model based on the Autoregressive Integrated Moving Average Model to analyze the sales data. Empirical analysis showed that the model considering the skewed distribution is effective. 展开更多
关键词 Forecasting OUTLIERS IMPROVED GARCH model Partial T-APARCH model based on ARIMA model
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Model based SOC estimation for high-power Li-ion battery packs used on FCHVs 被引量:1
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作者 戴海峰 Wei +2 位作者 Xuezhe Sun Zechang 《High Technology Letters》 EI CAS 2007年第3期322-326,共5页
关键词 扩展Kalman滤波 锂电池 充电状态 燃料电池混合汽车
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Evaluation of the Performance of Financial Support for Agriculture in Guizhou Province Using Secondary Relative Benefit Model Based on DEA
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作者 HUANG Qing-hua NIU Lei +1 位作者 WEI Xiao-ya XIE Lin-sha 《Asian Agricultural Research》 2012年第6期1-4,共4页
We use the secondary relative benefit model based on DEA to evaluate the performance of agricultural financial expenditure in Guizhou Province, which can give due consideration to the production effectiveness determin... We use the secondary relative benefit model based on DEA to evaluate the performance of agricultural financial expenditure in Guizhou Province, which can give due consideration to the production effectiveness determined by objective natural conditions, and management effectiveness of all regions (as decision-making body) in the use of financial fund for supporting agriculture. In general, there is north-south gradient difference in the performance of financial support for agriculture between regions in Guizhou Province. The drought in 2010 has significant impact on the technical efficiency in the whole province; the performance score of each item in Liupanshui City and Southwest Guizhou is very low; the technical efficiency and management efficiency in most regions need to be improved. In order to improve the performance of financial support for agriculture, we need to ensure the scale of input; at the same time, provide appropriate preferential financial policies for agricultural infrastructure, especially the construction of rural water conservancy, development and promotion of agricultural science and technology, and other fields; adopt the way of special check and acceptance of supporting projects to strengthen the use management of the fund for agriculture. 展开更多
关键词 FINANCIAL SUPPORT for AGRICULTURE PERFORMANCE eval
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A New Approach to Intelligent Model Based Predictive Control Scheme
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作者 A. H. MAZINAN M. F. KAZEMI 《Intelligent Information Management》 2010年第1期14-20,共7页
This paper describes a new approach to intelligent model based predictive control scheme for deriving a complex system. In the control scheme presented, the main problem of the linear model based predictive control th... This paper describes a new approach to intelligent model based predictive control scheme for deriving a complex system. In the control scheme presented, the main problem of the linear model based predictive control theory in dealing with severe nonlinear and time variant systems is thoroughly solved. In fact, this theory could appropriately be improved to a perfect approach for handling all complex systems, provided that they are firstly taken into consideration in line with the outcomes presented. This control scheme is organized based on a multi-fuzzy-based predictive control approach as well as a multi-fuzzy-based predictive model approach, while an intelligent decision mechanism system (IDMS) is used to identify the best fuzzy-based predictive model approach and the corresponding fuzzy-based predictive control approach, at each instant of time. In order to demonstrate the validity of the proposed control scheme, the single linear model based generalized predictive control scheme is used as a benchmark approach. At last, the appropriate tracking performance of the proposed control scheme is easily outperformed in comparison with previous one. 展开更多
关键词 multi-fuzzy-based PREDICTIVE control APPROACH multi-fuzzy-based PREDICTIVE model APPROACH INTELLIGENT DECISION mechanism system
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Optimal pricing decision model based on activity-based costing
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作者 王福胜 常庆芳 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第2期141-144,共4页
In order to find out the applicability of the optimal pricing decision model based on conventional cost behavior model after activity based costing has given strong shock to the conventional cost behavior model and it... In order to find out the applicability of the optimal pricing decision model based on conventional cost behavior model after activity based costing has given strong shock to the conventional cost behavior model and its assumptions, detailed analyses have been made using the activity based cost behavior and cost volume profit analysis model, and it is concluded from these analyses that the theory behind the construction of optimal pricing decision model is still tenable under activity based costing, but the conventional optimal pricing decision model must be modified as appropriate to the activity based costing based cost behavior model and cost volume profit analysis model, and an optimal pricing decision model is really a product pricing decision model constructed by following the economic principle of maximizing profit. 展开更多
关键词 企业 成本计算 最优定价决策模型 成本行为模型
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Model-Based Systems Engineering Approach to Design a Human Settlement to Better Serve Displaced People
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作者 Anicet Adjahossou 《Open Journal of Applied Sciences》 2024年第4期865-880,共16页
The challenge of transitioning from temporary humanitarian settlements to more sustainable human settlements is due to a significant increase in the number of forcibly displaced people over recent decades, difficultie... The challenge of transitioning from temporary humanitarian settlements to more sustainable human settlements is due to a significant increase in the number of forcibly displaced people over recent decades, difficulties in providing social services that meet the required standards, and the prolongation of emergencies. Despite this challenging context, short-term considerations continue to guide their planning and management rather than more integrated, longer-term perspectives, thus preventing viable, sustainable development. Over the years, the design of humanitarian settlements has not been adapted to local contexts and perspectives, nor to the dynamics of urbanization and population growth and data. In addition, the current approach to temporary settlement harms the environment and can strain limited resources. Inefficient land use and ad hoc development models have compounded difficulties and generated new challenges. As a result, living conditions in settlements have deteriorated over the last few decades and continue to pose new challenges. The stakes are such that major shortcomings have emerged along the way, leading to disruption, budget overruns in a context marked by a steady decline in funding. However, some attempts have been made to shift towards more sustainable approaches, but these have mainly focused on vague, sector-oriented themes, failing to consider systematic and integration views. This study is a contribution in addressing these shortcomings by designing a model-driving solution, emphasizing an integrated system conceptualized as a system of systems. This paper proposes a new methodology for designing an integrated and sustainable human settlement model, based on Model-Based Systems Engineering and a Systems Modeling Language to provide valuable insights toward sustainable solutions for displaced populations aligning with the United Nations 2030 agenda for sustainable development. 展开更多
关键词 Humanitarian Settlement Human Settlement Sustainability Systems Engineering model-based Systems Engineering Systems modeling Language
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A Custom Manipulator for Dental Implantation Through Model-Based Design 被引量:1
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作者 Anitha Govindhan Karnam Anantha Sunitha Sivanathan Kandhasamy 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期351-365,共15页
This paper presents a Model-Based Design(MBD)approach for the design and control of a customized manipulator intended for drilling and position-ing of dental implants accurately with minimal human intervention.While p... This paper presents a Model-Based Design(MBD)approach for the design and control of a customized manipulator intended for drilling and position-ing of dental implants accurately with minimal human intervention.While performing an intra-oral surgery for a prolonged duration within a limited oral cavity,the tremor of dentist's hand is inevitable.As a result,wielding the drilling tool and inserting the dental implants safely in accurate position and orientation is highly challenging even for experienced dentists.Therefore,we introduce a customized manipulator that is designed ergonomically by taking in to account the dental chair specifications and anthropomorphic data such that it can be readily mounted onto the existing dental chair.The manipulator can be used to drill holes for dental inserts and position them with improved accuracy and safety.Further-more,a thorough multi-body motion analysis of the manipulator was carried out by creating a virtual prototype of the manipulator and simulating its controlled movements in various scenarios.The overall design was prepared and validated in simulation using Solid works,MATLAB and Simulink through Model Based Design(MBD)approach.The motion simulation results indicate that the manipulator could be built as a prototype readily. 展开更多
关键词 model based design multi-body motion simulation custom manipulator orthodontic implants mathematical approach
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DiagDO: an efficient model based diagnosis approach with multiple observations
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作者 Huisi ZHOU Dantong OUYANG +1 位作者 Xinliang TIAN Liming ZHANG 《Frontiers of Computer Science》 SCIE EI CSCD 2023年第6期125-134,共10页
Model-based diagnosis(MBD)with multiple observations shows its significance in identifying fault location.The existing approaches for MBD with multiple observations use observations which is inconsistent with the pred... Model-based diagnosis(MBD)with multiple observations shows its significance in identifying fault location.The existing approaches for MBD with multiple observations use observations which is inconsistent with the prediction of the system.In this paper,we proposed a novel diagnosis approach,namely,the Diagnosis with Different Observations(DiagDO),to exploit the diagnosis when given a set of pseudo normal observations and a set of abnormal observations.Three ideas are proposed in this paper.First,for each pseudo normal observation,we propagate the value of system inputs and gain fanin-free edges to shrink the size of possible faulty components.Second,for each abnormal observation,we utilize filtered nodes to seek surely normal components.Finally,we encode all the surely normal components and parts of dominated components into hard clauses and compute diagnosis using the MaxSAT solver and MCS algorithm.Extensive tests on the ISCAS'85 and ITC'99 benchmarks show that our approach performs better than the state-of-the-art algorithms. 展开更多
关键词 model based diagnosis maximum satisfiability top-level diagnosis cardinality-minimal diagnosis subset-minimal diagnosis
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A Triple Nexus Water-Energy-Housing (WEH) Framework Modelling towards Improved Decision-Making in Humanitarian Operations
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作者 Anicet Adjahossou 《Open Journal of Applied Sciences》 2024年第4期927-949,共23页
Given the challenges facing most humanitarian operations worldwide, a change of approach is needed to ensure greater sustainability of humanitarian settlements right from the planning stage. Some studies attribute uns... Given the challenges facing most humanitarian operations worldwide, a change of approach is needed to ensure greater sustainability of humanitarian settlements right from the planning stage. Some studies attribute unsustainability to inadequate provision of basic resources and highlight the apparent bottlenecks that prevent access to the meaningful data needed to plan and remedy problems. Most operations have relied on an “ad hoc ism” approach, employing parallel and disconnected data processing methods, resulting in a wide range of data being collected without subsequent prioritization to optimize interconnections that could enhance performance. There have been little efforts to study the trade-offs potentially at stake. This work proposes a new framework enabling all subsystems to operate in a single system and focusing on data processing perspective. To achieve this, this paper proposes a Triple Nexus Framework as an attempt to integrate water, energy, and housing sector data derived from a specific sub-system within the overall system in the application of Model-Based Systems Engineering. Understanding the synergies between water, energy, and housing, Systems Engineering characterizes the triple nexus framework and identifies opportunities for improved decision-making in processing operational data from these sectors. Two scenarios illustrate how an integrated platform could be a gateway to access meaningful operational data in the system and a starting point for modeling integrated human settlement systems. Upon execution, the model is tested for nexus megadata processing, and the optimization simulation yielded 67% satisfactory results, demonstrating that an integrated system could improve sustainability, and that capacity building in service delivery is more than beneficial. 展开更多
关键词 Humanitarian Settlement Nexus Framework WATER ENERGY HOUSING Sustainability Systems Engineering (SE) model-based Systems Engineering (MBSE) Systems modeling Language (SysML)
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A Cautionary Note on the Application of GIS in Spatial Optimization Modeling
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作者 Bin Zhou 《Journal of Geographic Information System》 2024年第1期89-113,共25页
Spatial optimization as part of spatial modeling has been facilitated significantly by integration with GIS techniques. However, for certain research topics, applying standard GIS techniques may create problems which ... Spatial optimization as part of spatial modeling has been facilitated significantly by integration with GIS techniques. However, for certain research topics, applying standard GIS techniques may create problems which require attention. This paper serves as a cautionary note to demonstrate two problems associated with applying GIS in spatial optimization, using a capacitated p-median facility location optimization problem as an example. The first problem involves errors in interpolating spatial variations of travel costs from using kriging, a common set of techniques for raster files. The second problem is inaccuracy in routing performed on a graph directly created from polyline shapefiles, a common vector file type. While revealing these problems, the paper also suggests remedies. Specifically, interpolation errors can be eliminated by using agent-based spatial modeling while the inaccuracy in routing can be improved through altering the graph topology by splitting the long edges of the shapefile. These issues suggest the need for caution in applying GIS in spatial optimization study. 展开更多
关键词 Spatial Optimization GIS Agent-based model Covariance Function INTERPOLATION
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Modeling of a Lithium-Ion Capacitor and Its Charging and Discharging Circuit in a Model-Based Design
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作者 Kyoji Nakajo Shinji Aoki +4 位作者 Takashi Yatsuda Shuji Takahashi Kazuhiro Motegi Yasuhiro Kobayashi Yoichi Shiraishi 《Circuits and Systems》 2016年第1期11-22,共12页
For several years now, electric vehicles (EVs) have been expected to become widely available in the micro-mobility field. However, the insufficiency of such vehicles’ battery-charging and discharging performance has ... For several years now, electric vehicles (EVs) have been expected to become widely available in the micro-mobility field. However, the insufficiency of such vehicles’ battery-charging and discharging performance has limited their practical use. A hybrid energy storage system, which comprises a capacitor and battery, is a promising solution to this problem;however, to apply model-based designs, which are indispensable to embedded systems, such as the electronic control units used in EVs, a simple and accurate capacitor model is required. Within this framework, a lithium-ion capacitor (LIC) model is proposed, and its charging and discharging performances are evaluated against an actual LIC. The model corresponds accurately to the actual LIC, and the results indicate that the proposed LIC model will work well when used with Model-Based Design (MBD). 展开更多
关键词 model CAPACITOR LITHIUM-ION model based Design Electric Vehicle Battery HESS
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Color Image Segmentation Based on HSI Model 被引量:6
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作者 章毓晋 《High Technology Letters》 EI CAS 1998年第1期30-33,共4页
ColorImageSegmentationBasedonHSIModelZhangYujin(章毓晋),YaoYurong,HeYun(DepartmentofElectronicEngineering,Tsin... ColorImageSegmentationBasedonHSIModelZhangYujin(章毓晋),YaoYurong,HeYun(DepartmentofElectronicEngineering,TsinghuaUniversity,Be... 展开更多
关键词 modelbased coding HSI COLOR model COLOR transformation IMAGE SEGMENTATION
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Use of models in large-area forest surveys: comparing model-assisted, model-based and hybrid estimation 被引量:7
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作者 Goran Stahl Svetlana Saarela +8 位作者 Sebastian Schnell Soren Holm Johannes Breidenbach Sean P. Healey Paul L. Patterson Steen Magnussen Erik Naesset Ronald E. McRoberts Timothy G. Gregoire 《Forest Ecosystems》 SCIE CSCD 2016年第2期153-163,共11页
This paper focuses on the use of models for increasing the precision of estimators in large-area forest surveys. It is motivated by the increasing availability of remotely sensed data, which facilitates the developmen... This paper focuses on the use of models for increasing the precision of estimators in large-area forest surveys. It is motivated by the increasing availability of remotely sensed data, which facilitates the development of models predicting the variables of interest in forest surveys. We present, review and compare three different estimation frameworks where models play a core role: model-assisted, model-based, and hybrid estimation. The first two are well known, whereas the third has only recently been introduced in forest surveys. Hybrid inference mixes design- based and model-based inference, since it relies on a probability sample of auxiliary data and a model predicting the target variable from the auxiliary data.We review studies on large-area forest surveys based on model-assisted, model- based, and hybrid estimation, and discuss advantages and disadvantages of the approaches. We conclude that no general recommendations can be made about whether model-assisted, model-based, or hybrid estimation should be preferred. The choice depends on the objective of the survey and the possibilities to acquire appropriate field and remotely sensed data. We also conclude that modelling approaches can only be successfully applied for estimating target variables such as growing stock volume or biomass, which are adequately related to commonly available remotely sensed data, and thus purely field based surveys remain important for several important forest parameters. 展开更多
关键词 Design-based inference model-assisted estimation model-based inference Hybrid inference Nationalforest inventory Remote sensing Sampling
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Model-Based Degree Estimation of Unbalance and Misalignment in Flexible Coupling-rotor System 被引量:5
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作者 LI Changyou XU Minqiang +2 位作者 GUO Song WANG Yuewu WANG Rixin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第4期550-556,共7页
The condition of rotor system must be assessed in order to develop condition-based maintenance for rotating machinery. It is determined by multiple variables such as unbalance degree, misalignment degree, the amount o... The condition of rotor system must be assessed in order to develop condition-based maintenance for rotating machinery. It is determined by multiple variables such as unbalance degree, misalignment degree, the amount of bending deformation of the shaft, occurrence of shaft crack of rotor system and so on. The estimation of the degrees of unbalance and misalignment in flexible coupling-rotor system is discussed. The model-based approach is employed to solve this problem. The models of the equivalent external loads for unbalance and misalignment are derived and analyzed. Then, the degrees of unbalance and misalignment are estimated by analyzing the components of the equivalent external loads of which the frequencies are equal to the 1 and 2 times running frequency respectively. The equivalent external loads are calculated according to the dynamic equation of the original rotor system and the differences between the dynamical responses in normal case and the vibrations when the degree of unbalance or misalignment or both changes. The denoise method based on bandpass filter is used to decrease the effect of noise on the estimation accuracy. The numerical examples are given to show that the proposed approach can estimate the degrees of unbalance and misalignment of the flexible coupling-rotor system accurately. 展开更多
关键词 model-based approach degree estimation MISALIGNMENT UNBALANCE rotor system flexible coupling
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