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The unified ideal model of mean motion resonance of artificial satellites due to geopotential perturbations 被引量:1
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作者 ZHANG MingJiang ZHAO ChangYin +2 位作者 XIONG YongQing SUN RongYu ZHU TingLei 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第4期840-847,共8页
From Kaula's Earth gravitational potential written in classical orbital elements, the unified ideal model of mean motion resonance of artificial satellites due to geopotential perturbations is developed in this pa... From Kaula's Earth gravitational potential written in classical orbital elements, the unified ideal model of mean motion resonance of artificial satellites due to geopotential perturbations is developed in this paper first, through a suitable sequence of canonical transformations constructed by implicit functions. This unified ideal orbital resonance model is valid for all the commensurabilities between the rotational angular velocity of the Earth and the angular velocities of mean orbital motion of artificial satellites with arbitrary inclination and small eccentricity, and can be also transformed into Garfinkel's general expression of ideal resonance problem. Then 1/1 resonance of the 24-hour satellite with arbitrary inclination and small eccentricity is analyzed under the effect of harmonics of J2 and J 22 of the geopotential, based on the unified ideal model of mean motion resonance. The analytical expressions of the libration period and libration half width of the 1/1 resonance of the 24-hour satellite with arbitrary inclination and small eccentricity are presented. 展开更多
关键词 artificial satellite mean motion orbital resonance unified ideal model
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On the Ideal Model for Development of National Literature
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《Social Sciences in China》 1999年第4期122-131,192,共11页
关键词 On the ideal model for Development of National Literature
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Idealized cognitive models for students to strengthen the effect of music imagination
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作者 Fuduan PENG 《International Journal of Technology Management》 2015年第4期30-32,共3页
If there is no imagination, there is no music appreciation. It should create imaginary world for students in the music classroom teaching practice, and it should foster the students' musical imagination. Thus, collea... If there is no imagination, there is no music appreciation. It should create imaginary world for students in the music classroom teaching practice, and it should foster the students' musical imagination. Thus, colleagues can make discussion about strategies proposed including pilot background, context led, screen hygiene conditions and others. We use Cognitive Linguistic Theories to introduce idealized cognitive model and its theoretical basis and the intensified impact on student musical imagination. 展开更多
关键词 idealized cognitive model IMAGINATION INFLUENCE
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A Finite-Mode Model of Ideal Fluid Dynamics on the 2-Sphere
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《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1997年第3期68-81,共14页
AFinite-ModeModelofIdealFluidDynamicsonthe2-SphereWeiMozhengCRCforSouthernHemisphereMeteorologyCSIRODivision... AFinite-ModeModelofIdealFluidDynamicsonthe2-SphereWeiMozhengCRCforSouthernHemisphereMeteorologyCSIRODivisionofAtmosphericRese... 展开更多
关键词 A Finite-Mode model of ideal Fluid Dynamics on the 2-Sphere
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Study of the Influence of Nanoparticles on the Molecular Model of an Ideal Fluid
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作者 Mahammadali Ahmad oglu Ramazanov Mammad Samad oglu Aslanov 《Applied Mathematics》 2016年第9期908-911,共4页
In the article a molecular model of oil with nanoparticles on the basis of the model of ideal fluid is considered. It is assumed that the molecular model of the oil can be represented as a homogenous distribution of i... In the article a molecular model of oil with nanoparticles on the basis of the model of ideal fluid is considered. It is assumed that the molecular model of the oil can be represented as a homogenous distribution of identical molecules in space. It is assumed that the central interaction between the oil molecules and nanoparticles, results in a change of the model parameters. It is shown that for an ideal fluid the effect of nanoparticles is reduced to a change of the coefficient at the pressure. 展开更多
关键词 ideal Fluid Molecular model of Oil NANOPARTICLES Coefficient of Elasticity
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Demand Elasticity for China's Major Imported Agriculture Textile Material Based on Restricted Version of Source Differentiated Almost Ideal Demand System Model
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作者 TIAN Congying XIAO Haifeng 《Journal of Donghua University(English Edition)》 EI CAS 2018年第4期326-332,共7页
By comparing China's import of major imported agriculture textile material( cotton and wool),the characteristics of import are concluded. On this basis,a restricted version of source differentiated almost ideal de... By comparing China's import of major imported agriculture textile material( cotton and wool),the characteristics of import are concluded. On this basis,a restricted version of source differentiated almost ideal demand system( RSDAIDS) is used to estimate the income and price elasticity of major imported agriculture textile material from the major sources based on the data from 1992 to 2015. The results are shown as follows.( 1) Although the dependency on imported cotton is lower than wool, the fluctuation of cotton import is much more drastic; China's demand for cotton is relatively price elastic with higher expenditure elasticity compared with wool; besides,the existence of complementarity is proved between imported cotton and wool.( 2) According to the import elasticity of cotton,demand for cotton imported from India shows priority over cotton from other sources; demand for cotton imported from America is the most price-sensitive one; substitution among cotton from different sources is weak.( 3) According to the import elasticity of wool,wool imported from Uruguay has bright market prospects. In addition,wool imported from Australia has irreplaceable advantage than that from New Zealand. 展开更多
关键词 AGRICULTURE TEXTILE MATERIAL retricted VERSION of sourcedifferentiated almost ideal demand system (RSDA1DS) model importdemand estimation
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依托项目学习的高校外语专业课程思政IDEAL模式研究 被引量:4
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作者 周迎 《河北科技大学学报(社会科学版)》 2021年第4期69-74,共6页
语言与文化密不可分,跨文化教育是外语教育的重要组成部分。如何在跨文化对比中加深母语文化认同、坚定文化自信是高校外语专业课程思政建设的重要课题。以英语类专业“高级英语”课程为例,构建了依托项目学习的IDEAL课程思政模式,旨在... 语言与文化密不可分,跨文化教育是外语教育的重要组成部分。如何在跨文化对比中加深母语文化认同、坚定文化自信是高校外语专业课程思政建设的重要课题。以英语类专业“高级英语”课程为例,构建了依托项目学习的IDEAL课程思政模式,旨在推进课程教学与思政德育目标的共同达成。研究表明,该模式以语言为载体,以文化为内容,有效地促进了学习者知识、能力、素质的全面发展,实现了外语教学与文化价值观引领相统一。 展开更多
关键词 项目学习 课程思政 ideal模式 “高级英语”课程
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IDEAL模型的研究 被引量:5
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作者 万江平 郭荷清 夏志忠 《计算机应用研究》 CSCD 北大核心 2001年第12期32-34,共3页
首先介绍了软件过程能力成熟度模型 (SW CMM)及其实施方法论IDEAL模型的概念 ,接着阐明了IDEAL模型各个阶段的目的、任务和软件过程改进的管理 ,举例说明了用PDCA周期实施软件过程改进 ,并对ICASE模型进行了简单说明。最后结合中国传统... 首先介绍了软件过程能力成熟度模型 (SW CMM)及其实施方法论IDEAL模型的概念 ,接着阐明了IDEAL模型各个阶段的目的、任务和软件过程改进的管理 ,举例说明了用PDCA周期实施软件过程改进 ,并对ICASE模型进行了简单说明。最后结合中国传统文化和信息时代的特点对SW CMM实施方法论进行了若干讨论。 展开更多
关键词 软件过程能力成熟度模型 方法论 软件过程改进 软件开发 软件工程
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应用IDEAL模型在小型企业实施软件过程改进
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作者 吴洪丽 曾一 乔木 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2003年第8期18-22,共5页
软件过程改进是一个复杂的任务。SEI为了实现软件过程改进,提出了IDEAL模型。但这个模型是源于大企业的经验提出的。该文的目的在于研究IDEAL模型在小型企业的应用,并详细给出了一个运用IDEAL模型实施软件过程改进的过程。
关键词 ideal模型 小型软件企业 软件过程改进 软件开发
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Concept and application of ideal protein for pigs 被引量:11
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作者 Jaap van Milgen Jean-Yves Dourmad 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2015年第3期269-279,共11页
Knowledge about the amino acid requirements and the response of pigs to the amino acid supply is essential in feed formulation. A deficient AA supply results in a reduction in performance while an oversupply is costly... Knowledge about the amino acid requirements and the response of pigs to the amino acid supply is essential in feed formulation. A deficient AA supply results in a reduction in performance while an oversupply is costly and leads to excessive nitrogen excretion with a potentially negative environmental impact. Amino acid requirements are determined to a large extent by the protein deposition in the body and, for lactating sows, by the protein exported in the milk. The concept of ideal protein was developed more than 50 years ago and refers to a protein with an amino acid profile that exactly meets the animal's requirement so that all amino acids are equally limiting for performance. Because Lys typically is the first-limiting amino acid, the ideal amino acid profile is often expressed relative to Lys. Although the ideal protein profile is often assumed to be constant for a given production stage, (small) changes in the ideal protein profile can occur within a production stage. This can be caused by changes in the relative contribution of the different components of amino acid requirements during the productive life on the animal (e.g. changes in the relative contribution of growth and maintenance). Amino acids requirements can be determined experimentally using dose-response studies. The design of the study, the chosen response criterion, and the statistical model affect the requirement estimate. Although considerable experimental work has been carried out to determine the requirements for Lys, Met, Thr, and Trp in growing pigs (and to a lesser extent in sows), little is known about the requirements for the other essential amino acids. Experimental dose-response studies generally focus on the requirement and less on the overall response (i.e. what are the consequences of an amino acid deficiency?). This latter aspect is, to some extent, accounted for in modelling approaches that quantify the response of the animal to the amino acid supply in a dynamic way. The paper describes the origin of ideal protein and illustrates how fundamental concepts of amino acid nutrition have been integrated in practical modeling approaches for the nutrition of growing pigs and sows. 展开更多
关键词 Amino acids GESTATION GROWTH ideal protein LACTATION modeling PIGS
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The ideal landscape and its ecological planning approach in Mount Lushan National Park, China 被引量:2
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作者 XU Cong-rong HU Hai-sheng +2 位作者 WU Zhang-wen ZHENG Yan-ping ZHONG Lin-sheng 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第3期279-284,共6页
This paper described the main four basic models of ideal landscape in the Mount Lushan National Park as Kunlunshan model, Xumishan model, Peach flower land model, Christian model. Five typical places in Mount Lushan w... This paper described the main four basic models of ideal landscape in the Mount Lushan National Park as Kunlunshan model, Xumishan model, Peach flower land model, Christian model. Five typical places in Mount Lushan with the ideal landscape characteristics like the East Grove Temple, White Deer Cave Academy, Simplicity and Tranquility Monastery, Lushan Valley, and Villa-cluster of the East Valley were analyzed, and the integration of the basic models for each place was discussed to make the realistic landscape conform to the ideal needs. Moreover, the discussions also involved the characteristics of ideal landscape that are featured in resource, culture, structure, function, process, scale and region. In conclusion, ideal landscape in the Mount Lushan National Park was the product of the interaction between human and nature. Mount Lushan inherits the essence of Chinese traditional culture with a history of more than 1000 years; and it also absorbs the manna of the Western culture as well as the exchanges between nature and humanities together with the conflict and adaptation among different cultures. The natural landscape could be satisfied with the survival demand and cultural taste of mankind by the way of ecological planning. 展开更多
关键词 ecological planning ideal landscape landscape model Mount Lushan National Park
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H-bridge Hybrid Converter Modeling and Synthesize with Power Sharing Analysis
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作者 Aryan Sotoudeh Abdolreza Rahmati 《Energy and Power Engineering》 2012年第4期179-186,共8页
In this paper hybrid converters with double inputs are investigated. Mainly any possible topologies are constructed and only one of them is chosen and modeled in none ideal format, by state space averaging method. Aft... In this paper hybrid converters with double inputs are investigated. Mainly any possible topologies are constructed and only one of them is chosen and modeled in none ideal format, by state space averaging method. After that small signal model and equilibrium point of that model is calculated. Finally with power sharing analysis the best point in efficiency was calculated. 展开更多
关键词 HYBRID Converter NONE ideal modeling Small Signal Equilibrium Point Power SHARING
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Study on Theory of Cutting Edge Modeling and Helical Groove Machining of Nose Burr
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作者 刘井玉 刘华明 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第4期19-22,共4页
From the analysis of helical characteristics, ideal geometric models of cutting edge and helical groove of nose burr are developed to realize the ideal geometric model of helical groove of nose burr, in terms of not o... From the analysis of helical characteristics, ideal geometric models of cutting edge and helical groove of nose burr are developed to realize the ideal geometric model of helical groove of nose burr, in terms of not only the shape of cutting edge being accurately machined but also rake angle and depth of groove in fall compliance with design requirements. The fundamental relationship of too-groove engagment for groove shaping and the complex formulas related are verified by the example of machining and its computer simulation. 展开更多
关键词 NOSE BURR HELICAL GROOVE principle of MACHINING ideal geometric model computer simulation
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基于理想过程模型的探究学习评价——探究学习评价的新思路 被引量:2
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作者 杨开城 窦玲玉 《远程教育杂志》 CSSCI 北大核心 2024年第2期38-44,共7页
在教育情境下,探究学习被定义为旨在达到特定高阶能力目标的学习过程。因此,其评价应侧重于过程取向,而非结果取向。为刻画理想的探究学习过程并保留情境信息,特别是学习目标信息,需对特定的探究学习设计进行理想过程建模,所生成的理想... 在教育情境下,探究学习被定义为旨在达到特定高阶能力目标的学习过程。因此,其评价应侧重于过程取向,而非结果取向。为刻画理想的探究学习过程并保留情境信息,特别是学习目标信息,需对特定的探究学习设计进行理想过程建模,所生成的理想过程模型可作为评价实际发生的探究学习的标尺。探究学习的理想过程建模包括以下五个步骤:(1)完成探究学习的详案设计;(2)绘制探究学习活动所蕴含的知识建模图;(3)具体描述探究学习的整体过程;(4)将探究学习整个过程划分为多个环节,并绘制探究环节图;(5)将所有环节图按照探究学习的一般过程连接成一个整体,形成理想过程模型。对实际发生的探究学习也应进行上述操作,并在完成预处理后,生成探究学习的真实过程模型。通过比较真实过程模型与理想过程模型,找出差异点,依此可以评估实际发生的探究学习。这种评价方法不仅有助于了解探究学习的质量,还能为探究学习设计的改进提供反馈,更为重要的是,它可以使探究学习成为日常教学的一部分。 展开更多
关键词 探究学习 理想过程建模 理想过程模型 探究学习评价
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Ideal Drift Response Curve for Robust Optimal Damper Design for Elastic-Plastic MDOF Structures under Multi-Level Earthquakes Dedicated to Professor Karl S.Pister for his 95th birthday
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作者 Hiroki Akehashi Izuru Takewaki 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第12期1181-1207,共27页
A new method of robust damper design is presented for elastic-plastic multi-degree-of-freedom(MDOF)building structures under multi-level ground motions(GMs).This method realizes a design that is effective for various ... A new method of robust damper design is presented for elastic-plastic multi-degree-of-freedom(MDOF)building structures under multi-level ground motions(GMs).This method realizes a design that is effective for various levels of GMs.The robustness of a design is measured by an incremental dynamic analysis(IDA)curve and an ideal drift response curve(IDRC).The IDRC is a plot of the optimized maximum deformation under a constraint on the total damper quantity vs.the design level of the GMs.The total damper quantity corresponds to the total cost of the added dampers.First,a problem of generation of IDRCs is stated.Then,its solution algorithm,which consists of the sensitivity-based algorithm(SBA)and a local search method,is proposed.In the application of the SBA,the passive added dampers are removed sequentially under the specified-level GMs.On the other hand,the proposed local search method can search the optimal solutions for a constant total damper quantity under GMs’increased levels.In this way,combining these two algorithms enables the comprehensive search of the optimal solutions for various conditions of the status of the GMs and the total damper quantity.The influence of selecting the type of added dampers(oil,hysteretic,and so on)and the selection of the input GMs on the IDRCs are investigated.Finally,a robust optimal design problem is formulated,and a simple local search-based algorithm is proposed.A simple index using the IDRC and the IDA curve of the model is used as the objective function.It is demonstrated that the proposed algorithm works well in spite of its simplicity. 展开更多
关键词 Optimal damper placement robust damper design multi-level earthquake ideal drift response curve elastic-plastic MDOF model viscous damper hysteretic damper
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A Simplified Simulation Procedure and Analysis of a Photovoltaic Solar System Using a Single Diode Model
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作者 Robinson Ndegwa Elijah Ayieta +1 位作者 Justus Simiyu Nicodemus Odero 《Journal of Power and Energy Engineering》 2020年第9期65-93,共29页
A single diode model for a photovoltaic solar module is the most ideal and quick way of analyzing the module characteristics before implementing them in a solar plant. Solar modules manufacturers provide information f... A single diode model for a photovoltaic solar module is the most ideal and quick way of analyzing the module characteristics before implementing them in a solar plant. Solar modules manufacturers provide information for three critical points that are essential in I-V, P-V or P-I curves. In this study, we propose four separate simulation procedures to estimate the five-model parameters of an analogous single diode equivalent circuit by utilizing three cardinal points of the photovoltaic module I-V curve, described from experimental data using a solar simulator and manufacturer’s datasheet. The main objective is to extract and use the five unknown parameters of a single diode model to describe the photovoltaic system using I-V ad P-V plots under different environmental conditions. The most influential parameters that greatly alter the cardinal points defined at short circuit point (SCP), the maximum power point (MPP) and the open circuit point(OCP) are the ideality factor (</span><i><span style="font-family:Verdana;">n</span></i><span style="font-family:Verdana;">) and the diode saturation current (</span><i><span style="font-family:Verdana;">I<sub>o</sub></span></i><span style="font-family:Verdana;">). For a quick and fast convergence, we have determined the optimal ideality factor (</span><i><span style="font-family:Verdana;">n<sub>o</sub></span></i><span style="font-family:Verdana;">) and optimal saturation current (</span><i><span style="font-family:Verdana;">I<sub>oopt</sub></span></i><span style="font-family:Verdana;">) as the primary parameters by first assuming the optimal values of </span><i><span style="font-family:Verdana;">R<sub>sh</sub></span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">R<sub>s</sub> </span></i><span style="font-family:Verdana;">and </span><i><span style="font-family:Verdana;">I<sub>ph</sub> </span></i><span style="font-family:Verdana;">at standard test conditions (STC). Further, we evaluated the effects of </span><i><span style="font-family:Verdana;">I<sub>ph</sub></span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">R<sub>s</sub> </span></i><span style="font-family:Verdana;">and </span><i><span style="font-family:Verdana;">R<sub>sh</sub> </span></i><span style="font-family:Verdana;">on I-V and P-V curves by considering the values of </span><i><span style="font-family:Verdana;">n </span></i><span style="font-family:Verdana;">below </span><i><span style="font-family:Verdana;">n</span><sub><span style="font-family:Verdana;">o</span></sub></i><span style="font-family:Verdana;">. We have evaluated different iterative procedures of determining </span><i><span style="font-family:Verdana;">R<sub>sh</sub> </span></i><span style="font-family:Verdana;">and </span><i><span style="font-family:Verdana;">R<sub>s</sub> </span></i><span style="font-family:Verdana;">at open-circuit, short-circuit point and the maximum-power points. These procedures have been classified into four approaches that guarantees positive shunt and series resistance for </span><i><span style="font-family:Verdana;">n </span></i><span style="font-family:Verdana;">≤</span><i><span style="font-family:Verdana;"> n<sub>o</sub></span></i><span style="font-family:Verdana;">. These approaches have been categorized by deriving the saturation current as a dependent variable at each cardinal point with or without </span><i><span style="font-family:Verdana;">R<sub>s</sub> </span></i><span style="font-family:Verdana;">and </span><i><span style="font-family:Verdana;">R<sub>sh</sub> </span></i><span style="font-family:Verdana;">pair. The values obtained for the five parameters have been used to simulate the photovoltaic solar module characteristic curves with great precision at different air temperatures and irradiances, considering the effect of Nominal Operating Cell Temperature (NOCT). 展开更多
关键词 Five-Parameter model ideality Factor Saturation Current Series and Shunt Resistances
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Quantitative Interpretation of Gravity Anomalies in the Kribi-Campo Sedimentary Basin (South Cameroon) Based on Spectral Analysis and 2.5D Modelling: Structural Implications
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作者 Kue Petou Rokis Malquaire Owona Angue Marie Louise Clotilde +5 位作者 Njingti Nfor Eloundou Essama Lionel Mioumnde Arthur Paterne Kue Negham Martine Clémence Manguelle-Dicoum Eliezer Weiqi Song 《Open Journal of Earthquake Research》 2020年第3期240-254,共15页
Ground gravity survey was recently carried out in the Lolabe-Campo area, which constitutes the southern onshore portion of the Kribi-Campo sub-basin in South Cameroon. The obtained gravity data were processed and inte... Ground gravity survey was recently carried out in the Lolabe-Campo area, which constitutes the southern onshore portion of the Kribi-Campo sub-basin in South Cameroon. The obtained gravity data were processed and interpreted in order to elucidate the subsurface geology of the area in which preliminary studies highlighted the presence of an intrusive igneous body. In order to determine the nature and the characteristics of this body, spectral analysis, ideal body solution and 2.5D modelling methods were applied to the gravity data. The results suggest that the emplacement, breaking up and separation of the intrusive igneous body were the outcome of two tectonic events corresponding to an upward vertical translational tectonic movement followed by an anticlockwise rotational faulting tectonic movement. From a density contrast of 0.13 g&#183cm&#453, the two isolated bodies have an estimated density of 2.80 g&#183cm&#453 which is comparatively higher than the average density of 2.67 g&#183cm&#453 of the autochthonous rocks. These two blocks are completely surrounded by both sedimentary and metamorphic formations and are confined between the depths of 0.6 km and 3.5 km. The highly dense nature of the rocks and their location around the Atlantic Ocean led to the conclusion that the two intrusive bodies are composed principally of gabbro. The disposition and shape of the open zone resulting from the separation of the blocks are suggestive of a trap for the accumulation of hydrocarbons and mineral resources. 展开更多
关键词 Spectral Analysis ideal Body 2.5D modelLING Formation Depth INTRUSIVE BLOCKS
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共享制造环境下基于Z-RIM的QoS多方异质评价方法
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作者 刘明明 袁琦 禹春霞 《工业工程》 2024年第1期155-164,共10页
为解决共享制造环境下决策信息异质、候选服务数量动态变化的制造服务QoS评价问题,基于平台、服务需求方、服务提供方的三方决策信息,提出一种符合共享制造特点的QoS多方异质制造服务评价方法。通过精确数、语言变量和Z-number处理异质... 为解决共享制造环境下决策信息异质、候选服务数量动态变化的制造服务QoS评价问题,基于平台、服务需求方、服务提供方的三方决策信息,提出一种符合共享制造特点的QoS多方异质制造服务评价方法。通过精确数、语言变量和Z-number处理异质信息;基于共识最大化计算决策方权重向量,利用TrFWAA算子集结多方信息,依据离差最大化模型计算属性权重;在此基础上,采用RIM对各服务进行评估。结合共享制造环境下的制造业服务优选案例对提出的方法进行验证分析,结果表明该方法具有较好的实用性和优越性。 展开更多
关键词 共享制造 Z-number理论 参考理想法(RIM) 群决策 QOS评价
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基于组合赋权与TOPSIS模型的腹腔镜系统技术指标体系建立与应用
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作者 闫亭亭 刘孟翰 +3 位作者 贾佳 靳纯博 赵予涵 张璐璐 《医院管理论坛》 2024年第5期53-57,41,共6页
目的设计腹腔镜系统技术指标评价体系,用于客观评价产品技术水平,为医院腹腔镜系统的遴选提供支撑。方法采用文献研究法、访谈法以及德尔菲法确认评价体系指标,并通过优序图法及熵权法综合确定指标权重,最终通过理想排序法获取产品评价... 目的设计腹腔镜系统技术指标评价体系,用于客观评价产品技术水平,为医院腹腔镜系统的遴选提供支撑。方法采用文献研究法、访谈法以及德尔菲法确认评价体系指标,并通过优序图法及熵权法综合确定指标权重,最终通过理想排序法获取产品评价排序。结果腹腔镜系统评价体系纳入一级指标1项,二级指标6项,三级指标11项,可用于评价2D腹腔镜系统。参与真实测评的2D白光腹腔镜系统10个,荧光8个,均完成产品排序。结论本研究建立的腹腔镜系统技术评价指标体系可用于开展真实产品测评。 展开更多
关键词 组合权重 理想排序模型 腹腔镜系统 评价体系
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基于组合基元法的非理想模型装配偏差预测算法研究
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作者 张永亮 《制造技术与机床》 北大核心 2024年第7期155-163,共9页
基于模型定义(model-based definition,MBD)体系的装配偏差算法适用于赛博空间中理想数模的装配场景,但不适用于物理空间中非理想状态的装配场景,导致现场产生大量修配工作。针对这一问题,文章模拟真实的装配场景,基于零件的非理想状态... 基于模型定义(model-based definition,MBD)体系的装配偏差算法适用于赛博空间中理想数模的装配场景,但不适用于物理空间中非理想状态的装配场景,导致现场产生大量修配工作。针对这一问题,文章模拟真实的装配场景,基于零件的非理想状态,并将配合特征之间的拓扑关系考虑在内,对装配偏差的传递与累积过程展开研究,给出一种装配偏差预测算法。首先,针对孔轴配合与槽轴配合,将装配约束转化为定位点约束,依据最大实体原则,构造柱面点云的最小包围圆,确定接触状态,给出串行装配偏差算法,并将以上两种配合定义为两种基元,对应的装配偏差算法定义为两种独立基元算法。其次,基于平面贴合、孔轴配合与槽轴配合给出并行装配偏差算法,并将其定义为组合基元算法。最后,基于非理想模拟数据进行实例验证,达到了准确预测装配偏差的目标,为后续在赛博空间基于实测数据的装配偏差计算提供理论依据,以促进高精度装配。 展开更多
关键词 非理想模型 定位点约束 最小包围圆 装配偏差预测
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