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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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Multi-agent Based Hierarchy Simulation Models of Carrier-based Aircraft Catapult Launch 被引量:18
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作者 王维军 屈香菊 郭林亮 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第3期223-231,共9页
With the aid of multi-agent based modeling approach to complex systems, the hierarchy simulation models of carrier-based aircraft catapult launch are developed. Ocean, carrier, aircraft, and atmosphere are treated as ... With the aid of multi-agent based modeling approach to complex systems, the hierarchy simulation models of carrier-based aircraft catapult launch are developed. Ocean, carrier, aircraft, and atmosphere are treated as aggregation agents, the detailed components like catapult, landing gears, and disturbances are considered as meta-agents, which belong to their aggregation agent. Thus, the model with two layers is formed i.e. the aggregation agent layer and the meta-agent layer. The information communication among all agents is described. The meta-agents within one aggregation agent communicate with each other directly by information sharing, but the meta-agents, which belong to different aggregation agents exchange their information through the aggregation layer first, and then perceive it from the sharing environment, that is the aggregation agent. Thus, not only the hierarchy model is built, but also the environment perceived by each agent is specified. Meanwhile, the problem of balancing the independency of agent and the resource consumption brought by real-time communication within multi-agent system (MAS) is resolved. Each agent involved in carrier-based aircraft catapult launch is depicted, with considering the interaction within disturbed atmospheric environment and multiple motion bodies including carrier, aircraft, and landing gears. The models of reactive agents among them are derived based on tensors, and the perceived messages and inner frameworks of each agent are characterized. Finally, some results of a simulation instance are given. The simulation and modeling of dynamic system based on multi-agent system is of benefit to express physical concepts and logical hierarchy clearly and precisely. The system model can easily draw in kinds of other agents to achieve a precise simulation of more complex system. This modeling technique makes the complex integral dynamic equations of multibodies decompose into parallel operations of single agent, and it is convenient to expand, maintain, and reuse the program codes. 展开更多
关键词 multi-agent system (MAS) multi-agent based modeling (MABM) TENSOR carrier-based aircraft catapult launch hierarchy simulation model
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RoBGP:A Chinese Nested Biomedical Named Entity Recognition Model Based on RoBERTa and Global Pointer
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作者 Xiaohui Cui Chao Song +4 位作者 Dongmei Li Xiaolong Qu Jiao Long Yu Yang Hanchao Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第3期3603-3618,共16页
Named Entity Recognition(NER)stands as a fundamental task within the field of biomedical text mining,aiming to extract specific types of entities such as genes,proteins,and diseases from complex biomedical texts and c... Named Entity Recognition(NER)stands as a fundamental task within the field of biomedical text mining,aiming to extract specific types of entities such as genes,proteins,and diseases from complex biomedical texts and categorize them into predefined entity types.This process can provide basic support for the automatic construction of knowledge bases.In contrast to general texts,biomedical texts frequently contain numerous nested entities and local dependencies among these entities,presenting significant challenges to prevailing NER models.To address these issues,we propose a novel Chinese nested biomedical NER model based on RoBERTa and Global Pointer(RoBGP).Our model initially utilizes the RoBERTa-wwm-ext-large pretrained language model to dynamically generate word-level initial vectors.It then incorporates a Bidirectional Long Short-Term Memory network for capturing bidirectional semantic information,effectively addressing the issue of long-distance dependencies.Furthermore,the Global Pointer model is employed to comprehensively recognize all nested entities in the text.We conduct extensive experiments on the Chinese medical dataset CMeEE and the results demonstrate the superior performance of RoBGP over several baseline models.This research confirms the effectiveness of RoBGP in Chinese biomedical NER,providing reliable technical support for biomedical information extraction and knowledge base construction. 展开更多
关键词 BIOMEDICINE knowledge base named entity recognition pretrained language model global pointer
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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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A Feature-Based Parametric Product Modeling System in CIMS Environment 被引量:4
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作者 李海龙 《High Technology Letters》 EI CAS 1997年第1期13-16,共4页
This paper proposes an approach of developing the feature based parametric product modeling system which is suitable for integrated engineering design in CIMS environment.The architecture of ZD--MCADII and the charact... This paper proposes an approach of developing the feature based parametric product modeling system which is suitable for integrated engineering design in CIMS environment.The architecture of ZD--MCADII and the characteristics of its each module are introduced in detail. ZD--MCADII’s product data is managed by an object--oriented database management system OSCAR, and the product model is built according to the standard STEP. The product design is established on a unified product model, and all the product data are globally associated in ZD--MCADII. ZD--MCADII provides various design features to facilitate the product design, and supports the integrity of CAD, CAPP and CAM. 展开更多
关键词 CIMS FEATURE based modeling PARAMETRIC design PRODUCT model OODB
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Color-texture segmentation using JSEG based on Gaussian mixture modeling 被引量:4
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作者 Wang Yuzhong Yang Jie Zhou Yue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期24-29,共6页
An improved approach for J-value segmentation (JSEG) is presented for unsupervised color image segmentation. Instead of color quantization algorithm, an automatic classification method based on adaptive mean shift ... An improved approach for J-value segmentation (JSEG) is presented for unsupervised color image segmentation. Instead of color quantization algorithm, an automatic classification method based on adaptive mean shift (AMS) based clustering is used for nonparametric clustering of image data set. The clustering results are used to construct Gaussian mixture modelling (GMM) of image data for the calculation of soft J value. The region growing algorithm used in JSEG is then applied in segmenting the image based on the multiscale soft J-images. Experiments show that the synergism of JSEG and the soft classification based on AMS based clustering and GMM overcomes the limitations of JSEG successfully and is more robust. 展开更多
关键词 color image segmentation JSEG adaptive mean shift based dustering Gaussian mixture modeling soft J-value.
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Performance-based Research Funding in Denmark: The Adoption and Translation of the Norwegian Model 被引量:2
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作者 Kaare Aagaard 《Journal of Data and Information Science》 CSCD 2018年第4期20-30,共11页
Purpose: The main goal of this study is to outline and analyze the Danish adoption and translation of the Norwegian Publication Indicator. Design/methodology/approach: The study takes the form of a policy analysis mai... Purpose: The main goal of this study is to outline and analyze the Danish adoption and translation of the Norwegian Publication Indicator. Design/methodology/approach: The study takes the form of a policy analysis mainly drawing on document analysis of policy papers, previously published studies and grey literature. Findings: The study highlights a number of crucial factors that relate both to the Danish process and to the final Danish result underscoring that the Danish BFI model is indeed a quite different system than its Norwegian counterpart. One consequence of these process-and design differences is the fact that the broader legitimacy of the Danish BFI today appears to be quite poor. Reasons for this include: unclear and shifting objectives throughout the process; limited willingness to take ownership of the model among stakeholders; lack of communication throughout the implementation process and an apparent underestimation of the challenges associated with the use of bibliometric indicators. Research limitation: The conclusions of the study are based on the authors’ interpretation of a long drawn and complex process with many different stakeholders involved. The format of this article does not allow for a detailed documentation of all elements, but further details can be provided upon request. Practical implications: The analysis may feed into current policy discussions on the future of the Danish BFI. Originality/value: Some elements of the present analysis have previously been published in Danish outlets, but this article represents the first publication on this issue targeting a broader international audience. 展开更多
关键词 Norwegian model Performance based funding BIBLIOMETRICS
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An elasto-plastic constitutive model of moderate sandy clay based on BC-RBFNN 被引量:1
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作者 彭相华 王智超 +2 位作者 罗涛 余敏 罗迎社 《Journal of Central South University》 SCIE EI CAS 2008年第S1期47-50,共4页
Application research of neural networks to geotechnical engineering has become a hotspot nowadays.General model may not reach the predicting precision in practical application due to different characteristics in diffe... Application research of neural networks to geotechnical engineering has become a hotspot nowadays.General model may not reach the predicting precision in practical application due to different characteristics in different fields.In allusion to this,an elasto-plastic constitutive model based on clustering radial basis function neural network(BC-RBFNN) was proposed for moderate sandy clay according to its properties.Firstly,knowledge base was established on triaxial compression testing data;then the model was trained,learned and emulated using knowledge base;finally,predicting results of the BC-RBFNN model were compared and analyzed with those of other intelligent model.The results show that the BC-RBFNN model can alter the training and learning velocity and improve the predicting precision,which provides possibility for engineering practice on demanding high precision. 展开更多
关键词 ELASTO-PLASTIC CONSTITUTIVE model artificial NEURAL NETWORK BC-RBFNN(based on clustering radial basis function NEURAL network) MODERATE SANDY clay
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Roll System and Stock's Multi-parameter Coupling Dynamic Modeling Based on the Shape Control of Steel Strip 被引量:3
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作者 Yang ZHANG Yan PENG +1 位作者 Jianliang SUN Yong ZANG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期614-624,共11页
The existence of rolling deformation area in the rolling mill system is the main characteristic which dis- tinguishes the other machinery. In order to analyze the dynamic property of roll system's flexural deformatio... The existence of rolling deformation area in the rolling mill system is the main characteristic which dis- tinguishes the other machinery. In order to analyze the dynamic property of roll system's flexural deformation, it is necessary to consider the transverse periodic movement of stock in the rolling deformation area which is caused by the flexural deformation movement of roll system simul- taneously. Therefore, the displacement field of roll system and flow of metal in the deformation area is described by kinematic analysis in the dynamic system. Through intro- ducing the lateral displacement function of metal in the deformation area, the dynamic variation of per unit width rolling force can be determined at the same time. Then the coupling law caused by the co-effect of rigid movement and flexural deformation of the system structural elements is determined. Furthermore, a multi-parameter coupling dynamic model of the roll system and stock is established by the principle of virtual work. More explicitly, the cou- pled motion modal analysis was made for the roll system. Meanwhile, the analytical solutions for the flexural defor- mation movement's mode shape functions of rolls are discussed. In addition, the dynamic characteristic of the lateral flow of metal in the rolling deformation area has been analyzed at the same time. The establishment ofdynamic lateral displacement function of metal in the deformation area makes the foundation for analyzing the coupling law between roll system and rolling deformation area, and provides a theoretical basis for the realization of the dynamic shape control of steel strip. 展开更多
关键词 Roll system Rolling deformation area Coupling dynamic model Mode shape function - Lateraldisplacement function
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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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3D Geometry-Based UAV-MIMO Channel Modeling and Simulation 被引量:15
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作者 Rubing Jia Yiran Li +1 位作者 Xiang Cheng Bo Ai 《China Communications》 SCIE CSCD 2018年第12期64-74,共11页
A more general narrowband regular-shaped geometry-based statistical model(RS-GBSM) combined with the line of sight(LoS) and single bounce(SB) rays for unmanned aerial vehicle(UAV) multiple-input multiple-output(MIMO) ... A more general narrowband regular-shaped geometry-based statistical model(RS-GBSM) combined with the line of sight(LoS) and single bounce(SB) rays for unmanned aerial vehicle(UAV) multiple-input multiple-output(MIMO) channel is proposed in this paper. The channel characteristics, including space-time correlation function(STCF), Doppler power spectral density(DPSD), level crossing rate(LCR) and average fade duration(AFD), are derived based on the single sphere reference model for a non-isotropic environment. The corresponding sum-of-sinusoids(SoS) simulation models including both the deterministic model and statistical model with finite scatterers are also proposed for practicable implementation. The simulation results illustrate that the simulation models well reproduce the channel characteristics of the single sphere reference model with sufficient simulation scatterers. And the statistical model has a better approximation of the reference model in comparison with the deterministic one when the simulation trials of the stochastic model are sufficient. The effects of the parameters such as flight height, moving direction and Rice factor on the characteristics are also studied. 展开更多
关键词 UAV-MIMO geometry-based model CHANNEL CHARACTERISTICS simulation model
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Model based SOC estimation for high-power Li-ion battery packs used on FCHVs 被引量:2
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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
A model based method which recruited the extended Kalman filter (EKF) to estimate the full state of charge (SOC) of Li-ion battery was proposed. The underlying dynamic behavior of the cell pack was described based... A model based method which recruited the extended Kalman filter (EKF) to estimate the full state of charge (SOC) of Li-ion battery was proposed. The underlying dynamic behavior of the cell pack was described based on an equivalent circuit comprising of two capacitors and three resistors. Measurements in two tests were applied to compare the SOC estimated by model based EKF estimation with the SOC calculated by coulomb counting. Results have shown that the proposed method is able to perform a good estimation of the SOC of battery packs. Moreover, a corresponding battery management systems (BMS) including software and hardware based on this method was designed. 展开更多
关键词 model based extended Kalman filter (EKF) state of charge (SOC) estimation Liion batteries fuel cell hybrid vehicles (FCHV)
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Flow Field and Temperature Field in GaN-MOCVD Reactor Based on Computational Fluid Dynamics Modeling 被引量:1
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作者 梅书哲 王权 +8 位作者 郝美兰 徐健凯 肖红领 冯春 姜丽娟 王晓亮 刘峰奇 徐现刚 王占国 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第9期82-86,共5页
Metal organic chenlical vapor deposition (AIOCVD) growth systems arc one of the. main types of equipment used for growing single crystal materials, such as GaN. To obtain fihn epitaxial materials with uniform perfor... Metal organic chenlical vapor deposition (AIOCVD) growth systems arc one of the. main types of equipment used for growing single crystal materials, such as GaN. To obtain fihn epitaxial materials with uniform performanee, the flow field and ternperature field in a GaN-MOCVD reactor are investigated by modeling and simulating. To make the simulation results more consistent with the actual situation, the gases in the reactor are considered to be compressible, making it possible to investigate the distributions of gas density and pressure in the reactor. The computational fluid dynamics method is used to stud,v the effects of inlet gas flow velocity, pressure in the reactor, rotational speed of graphite susceptor, and gases used in the growth, which has great guiding~ significance for the growth of GaN fihn materials. 展开更多
关键词 MOCVD Flow Field and Temperature Field in GaN-MOCVD Reactor based on Computational Fluid Dynamics modeling GAN
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A Numerical Algorithm Based on Quadratic Finite Element for Two-Dimensional Nonlinear Time Fractional Thermal Diffusion Model 被引量:3
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作者 Yanlong Zhang Baoli Yin +2 位作者 Yue Cao Yang Liu Hong Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第3期1081-1098,共18页
In this article,a high-order scheme,which is formulated by combining the quadratic finite element method in space with a second-order time discrete scheme,is developed for looking for the numerical solution of a two-d... In this article,a high-order scheme,which is formulated by combining the quadratic finite element method in space with a second-order time discrete scheme,is developed for looking for the numerical solution of a two-dimensional nonlinear time fractional thermal diffusion model.The time Caputo fractional derivative is approximated by using the L2-1formula,the first-order derivative and nonlinear term are discretized by some second-order approximation formulas,and the quadratic finite element is used to approximate the spatial direction.The error accuracy O(h3+t2)is obtained,which is verified by the numerical results. 展开更多
关键词 Quadratic finite element two-dimensional nonlinear time fractional thermal diffusion model L2-1formula.
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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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技术创新难度对高科技企业最优创新投入的影响——基于Agent-Based Model的分析 被引量:1
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作者 伍云鹏 董正英 《科技与经济》 2014年第5期44-48,共5页
通过Agent-Based Model模拟了高技术企业的发展环境,分析了不同技术创新门槛下企业技术的发展状况。研究发现,高技术创新门槛阻碍了市场最高技术水平的发展,但能提升市场平均技术水平及公司数目。同时,企业研发活动存在能实现最大技术... 通过Agent-Based Model模拟了高技术企业的发展环境,分析了不同技术创新门槛下企业技术的发展状况。研究发现,高技术创新门槛阻碍了市场最高技术水平的发展,但能提升市场平均技术水平及公司数目。同时,企业研发活动存在能实现最大技术增长的最优创新研发投入比例,并且随着技术创新门槛的提升,企业的研发政策向模仿性投入倾斜。由此可知,针对有高技术创新门槛的高科技企业,政府应提升专利保护强度以影响企业的最优研发政策,保证高新技术产业的健康发展。 展开更多
关键词 AGENT-based model 高技术产业 技术创新门槛
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Experts' Knowledge Fusion in Model-Based Diagnosis Based on Bayes Networks 被引量:5
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作者 Deng Yong & Shi Wenkang School of Electronics & Information Technology, Shanghai Jiaotong University, Shanghai 200030, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第2期25-30,共6页
In previous researches on a model-based diagnostic system, the components are assumed mutually independent. Howerver , the assumption is not always the case because the information about whether a component is faulty ... In previous researches on a model-based diagnostic system, the components are assumed mutually independent. Howerver , the assumption is not always the case because the information about whether a component is faulty or not usually influences our knowledge about other components. Some experts may draw such a conclusion that 'if component m 1 is faulty, then component m 2 may be faulty too'. How can we use this experts' knowledge to aid the diagnosis? Based on Kohlas's probabilistic assumption-based reasoning method, we use Bayes networks to solve this problem. We calculate the posterior fault probability of the components in the observation state. The result is reasonable and reflects the effectiveness of the experts' knowledge. 展开更多
关键词 model-based diagnosis Experts' knowledge Probabilistic assumption-based reasoning Bayes networks.
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Modeling of Carrier-based Aircraft Ski Jump Take-off Based on Tensor 被引量:8
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作者 刘伟伟 屈香菊 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2005年第4期326-335,共10页
A general mathematical model of carrier-based aircraft ski jump take-off is derived based on tensor. The carrier, the aircraft body and the movable parts of the landing gears are treated as independent entities. These... A general mathematical model of carrier-based aircraft ski jump take-off is derived based on tensor. The carrier, the aircraft body and the movable parts of the landing gears are treated as independent entities. These entities are assembled into a multi-rigid-body system with flexible links. Dynamical equations of each entity are derived on the basis of the Newton law and the Euler transformation. Using the invariance property of the tensor, the dynamical and kinematical equations are converted to tensor forms which are invariant under time-dependent coordinate transformations. Then the tensor-formed equations are expressed by the matrix operation. Differential equation group of the matrix form is formulated for the programming. The closure of the model is discussed, and the simulation results are given. 展开更多
关键词 mathematical model TENSOR carrier-based aircraft ski jump TAKE-OFF
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Physics-based Modeling and Simulation for Motional Cable Harness Design 被引量:6
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作者 LIU Jianhua ZHAO Tao +1 位作者 NING Ruxin LIU Jiashun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第5期1075-1082,共8页
The design work of motional cable in products is vital due to the difficulty in estimating the potential issues in current researches.In this paper,a physics-based modeling and simulation method for the motional cable... The design work of motional cable in products is vital due to the difficulty in estimating the potential issues in current researches.In this paper,a physics-based modeling and simulation method for the motional cable harness design is presented.The model,based on continuum mechanics,is established by analyzing the force of microelement in equilibrium.During the analysis procedure,three coordinate systems:inertial,Frenet and main-axis coordinate systems are used.By variable substitution and dimensionless processing,the equation set is discretized by differential quadrature method and subsequently becomes an overdetermined nonlinear equation set with boundary conditions solved by Levenberg-Marquardt method.With the profile of motional cable harness obtained from the integral of arithmetic solution,a motion simulation system based on"path"and"profile"as well as the experimental equipments is built.Using the same parameters as input for the simulation and the real cable harness correspondingly,the issue in designing,such as collision,can be easily found by the simulation system.This research obtains a better result which has no potential collisions by redesign,and the proposed method can be used as an accurate and efficient way in motional cable harness design work. 展开更多
关键词 motional cable harness physics-based modeling motion simulation Kirchhoff rod
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SELECTING CLUSTER MODEL IN Sn - BASED SOLDER ALLOY DESIGN WITH DV - X_α CALCULATION METHOD
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作者 C. Q. Wang and W. F. Feng National ho. of Advanced welding Technolgy, HIT, Harbin 150001,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期84-88,共5页
Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have ... Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have been investigated by employing DV - Xa method, in which different cluster models were adopted to calculate electron structure.It is proved that some regulations must be taken into ac- count in order to carry out alloy design calculation successfully,which are described in this paper in detail. 展开更多
关键词 Cluster model Sn - based alloy design DV - X_a calculation method DOS
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