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IUID Method-Mix: Towards a Systematic Approach for Intercultural User Interface Design (IUID)
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作者 Rüdiger Heimgartner 《Journal of Computer and Communications》 2019年第7期162-194,共33页
A method-mix for intercultural user interface design (IUID) is explained and exemplified by application examples based on a hybrid approach covering cultural contexts in human-computer interaction (HCI) design using a... A method-mix for intercultural user interface design (IUID) is explained and exemplified by application examples based on a hybrid approach covering cultural contexts in human-computer interaction (HCI) design using a model of culturally influenced HCI. Cultural influence on HCI is described using cultural variables for user interface design. Assumptions and empirical results regarding the influence of culture on HCI, considering the path of the information processing and the interaction style between Chinese and German users are explained based on cultural models. Subsequent indicators represent the relationship between culture and HCI (culturally imprinted by the user). Correlations adopted theoretically between cultural dimensions and variables for HCI design were investigated. These correlations represent relevant constituents of a model for culturally influenced HCI. Considerations applying this model and evidence for the proper application of the IUID method-mix are presented elucidating why and how cultural aspects play a role in HCI design and usability/UX engineering. The IUID method-mix serves to inspire HCI engineers in the requirement analysis phase as well as HCI designers in the design phase. The readers are thereby sensitized to the challenges of intercultural usability/UX engineering and intercultural HCI design and will be equipped with methodological knowledge relevant to the derivation of design recommendations for user interface design for and in their desired cultural contexts. Finally, implications for practitioners are shown, including HCI style scores and practical design recommendations, to prognosticate the effort and the expenditures for considering the cultural context in IUID. 展开更多
关键词 CULTURE Human Factors UX Usability Engineering INTERCULTURAL User Interface DESIGN method MIX HCI Dimensions HCI HMI Cross-Cultural DESIGN INTERCULTURAL Culture-Centered methods Tools Standards State of Research Cultural Differences COMMUNICATION Understanding Empathy INTERCULTURAL COMMUNICATION INTERCULTURAL HCI DESIGN Process Cycle IUID
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Computational Methods in the Theory of Synthesis of Radio and Acoustic Radiating Systems
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作者 Petro Savenko 《Applied Mathematics》 2013年第3期523-549,共27页
A brief review of the works of the author and his co-authors on the application of nonlinear analysis, numerical and analytical methods for solving the nonlinear inverse problems (synthesis problems) for optimizing th... A brief review of the works of the author and his co-authors on the application of nonlinear analysis, numerical and analytical methods for solving the nonlinear inverse problems (synthesis problems) for optimizing the different types of radiating systems, is presented in the paper. The synthesis problems are formulated in variational statements and further they are reduced to research and numerical solution of nonlinear integral equations of Hammerstein type. The existence theorems are proof, the investigation methods of nonuniqueness problem of solutions and numerical algorithms of finding the optimal solutions are proved. 展开更多
关键词 NONLINEAR Inverse Problems Synthesis of Radiating SYSTEMS NONLINEAR Equations of HAMMERSTEIN Type Branching of SOLUTIONS NONLINEAR TWO-PARAMETER Spectral Problem Localization of SOLUTIONS Numerical methods and Algorithms Convergence of ITERATIVE Processes
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Improvement Detecting Method of Optical Axes Parallelism of Shipboard Photoelectrical Theodolite Based on Image Processing 被引量:3
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作者 Huihui Zou 《Optics and Photonics Journal》 2017年第8期127-133,共7页
An improvement detecting method was proposed according to the disadvantages of testing method of optical axes parallelism of shipboard photoelectrical theodolite (short for theodolite) based on image processing. Point... An improvement detecting method was proposed according to the disadvantages of testing method of optical axes parallelism of shipboard photoelectrical theodolite (short for theodolite) based on image processing. Pointolite replaced 0.2'' collimator to reduce the errors of crosshair images processing and improve the quality of image. What’s more, the high quality images could help to optimize the image processing method and the testing accuracy. The errors between the trial results interpreted by software and the results tested in dock were less than 10'', which indicated the improve method had some actual application values. 展开更多
关键词 IMPROVEMENT Detecting method SHIPBOARD Photoelectrical THEODOLITE OPTICAL Axes PARALLELISM Image processing
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Induction Heating in the Processing of Ti &Zr
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作者 Victor Demidovich Irina Rastvorova 《Journal of Electromagnetic Analysis and Applications》 2014年第13期404-412,共9页
Induction heating has important applications in science and industry. The method of induction heating can be successfully used for melting and heat treatment of titanium and zirconium alloys. Different applications us... Induction heating has important applications in science and industry. The method of induction heating can be successfully used for melting and heat treatment of titanium and zirconium alloys. Different applications using induction precise heating before plastic deformation are discussed in this paper. For alloys of many metals such as titanium, zirconium, niobium, tantalum, etc., it is important to provide precision heating with a high degree of homogeneity of the temperature field and strict adherence to the condition of heating. This is explained by polymorphism of the alloys based on these metals, their chemical activity at high temperatures and the specific thermal and electrical properties. It is very important for induction heating to define the extreme achievable unevenness of the temperature field. For special alloys it is necessary to use resistance furnaces for homogenization of billets’ temperature after heating in the inductors. Optimal control can be used for massive billets to reduce significantly the heating time, energy expenses and to improve the quality of the temperature field distribution. Optimization of induction heating process can be achieved by synchronous solution of the problem of optimal control and design with specially developed models. 展开更多
关键词 Induction HEATING Optimal Control The method of ELECTROMAGNETIC processing ELECTROMAGNETIC Numerical Analysis PRECISE HEATING MELTING and Heat Treatment of Titanium and ZIRCONIUM Alloys
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Modified Differential Transform Method (DTM) Simulation of Hydromagnetic Multi-Physical Flow Phenomena from a Rotating Disk
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作者 Mohammad Mehdi Rashidi Esmael Erfani +1 位作者 Osman Anwar Bég Swapan Kumar Ghosh 《World Journal of Mechanics》 2011年第5期217-230,共14页
A similarity solution for the steady hydromagnetic convective heat and mass transfer with slip flow from a spinning disk with viscous dissipation and Ohmic heating yields a system of non-linear, coupled, ordinary diff... A similarity solution for the steady hydromagnetic convective heat and mass transfer with slip flow from a spinning disk with viscous dissipation and Ohmic heating yields a system of non-linear, coupled, ordinary differential equations. These equations are analytically solved by applying a newly developed method namely the DTM-Padé technique which is a combination of the Differential Transform Method (DTM) and the Padé approximation. A full analytical solution is presented, as a benchmark for alternative numerical solutions. DTM-Padé is implemented without requiring linearization, discretization, or perturbation, and holds significant potential for solving strongly nonlinear differential equations which arise frequently in fluid dynamics. The regime studied is shown to be controlled by the slip parameter (γ), magnetohydrodynamic body force parameter (M), Eckert (viscous heating) number (Ec), Schmidt number (Sc), Soret number (Sr), Dufour number (Du) and Prandtl number (Pr). The influence of selected parameters on the evolution of dimensionless velocity, temperature and concentration distributions is studied graphically. Increasing magnetic field (M) is found to significantly inhibit the radial (f) and tangential (g) velocities, but to accentuate the axial velocity field (h);furthermore temperature (θ) and concentration (φ) are both enhanced with increasing M. Increasing Soret number (Sr) acts to boost the dimensionless concentration (φ). Temperatures are significantly elevated in the boundary layer regime with a rise in Eckert number (Ec). Excellent correlation between the DTM-Padé technique and numerical (shooting) solutions is achieved. The model has important applications in industrial energy systems, process mechanical engineering, electromagnetic materials processing and electro-conductive chemical transport processes. 展开更多
关键词 Differential Transform method Padé APPROXIMANTS THERMAL-DIFFUSION Heat Transfer SORET Effect BOUNDARY-LAYERS Hydromagnetics Slip Dissipation Electromagnetic processing of Materials
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Research on the Processing Methods of the Computer Format Information Flow in the Network English Translation System
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作者 ZHANG Jing 《International English Education Research》 2019年第3期61-63,共3页
The development o f the network technology, and especially the web search engine, has brought great changes to the field of the English translation. Translators can acquire the background information of the translated... The development o f the network technology, and especially the web search engine, has brought great changes to the field of the English translation. Translators can acquire the background information of the translated texts by using the web search engine correctly, inquire about the correct translation methods of the rare professional terms, apply the fixed sentence patterns, and check the correctness of the translation, so as to improve the translation speed and quality. 展开更多
关键词 NETWORK mechanism ENGLISH TRANSLATION SYSTEM COMPUTER FORMAT information flow processing method
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Rapid Determination of Seed Number and Thousand Kernel Weight of Asparagus officinalis L.Using Image Processing Method
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作者 Huimin GAO Yu TIAN +1 位作者 Zhiqiang LIU Yanpo CAO 《Asian Agricultural Research》 2019年第11期53-55,共3页
Asparagus officinalis L.is favored by its high health function,but its hybrid seeds are expensive.The amount of seed,seed plumpness and germination rate are related to the production costs of breeding enterprises and ... Asparagus officinalis L.is favored by its high health function,but its hybrid seeds are expensive.The amount of seed,seed plumpness and germination rate are related to the production costs of breeding enterprises and large growers.Therefore,it is necessary to investigate the seed number and thousand kernel weight of A.officinalis L.This study developed a quick and accurate method to measure the seed number and thousand kernel weight of A.officinalis L.using image processing technology.Seed sample of A.officinalis L.was scanned with 200 dpi resolution,and the seed number was then obtained using Image-ProPlus software.After weighing the seeds,thousand kernel weight was finally calculated.By recording‘macro’,the batch processing of the samples can also be realized.This method is simple and accurate,and can greatly save the time of investigation. 展开更多
关键词 ASPARAGUS OFFICINALIS L. SEED number Thousand KERNEL WEIGHT Image processing method
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Wireless Infrared Pyrometer with Fiber Optic: Construction and Processing Algorithms
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作者 Igor Ya. Orlov Igor A. Nikiforov Alexander V. Afanasjev 《Wireless Engineering and Technology》 2014年第2期25-33,共9页
In this paper, developed wireless portable infrared pyrometer with dual channel fiber optic is described. The pyrometer measures surface temperature in wide infrared spectral range of 2 - 25 um. A data processing algo... In this paper, developed wireless portable infrared pyrometer with dual channel fiber optic is described. The pyrometer measures surface temperature in wide infrared spectral range of 2 - 25 um. A data processing algorithm based on the methods of synchronous detection providing 展开更多
关键词 INFRARED Radiometer INFRARED PYROMETER INFRARED Fiber Optic Synchronous Detection method WIRELESS DATA Transmission Reference Oscillation Temperature Compensation DATA processing ALGORITHMS
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A new PAT application: Optimization of processing methods for honeysuckle flower (Lonicerae Japonicae Flos) and wild honeysuckle flower (Lonicerae Flos) 被引量:1
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作者 Jiangbo Hao Zhisheng Wu +2 位作者 Weidong Li Zhongshuang Zhang Jinrui Gu 《Journal of Traditional Chinese Medical Sciences》 2018年第2期199-205,共7页
Objective:A novel processing analytical framework of Chinese Material Medica (CMM) includes breeding process analysis,planting process analysis,producing process analysis and manufacture process analysis.In order to s... Objective:A novel processing analytical framework of Chinese Material Medica (CMM) includes breeding process analysis,planting process analysis,producing process analysis and manufacture process analysis.In order to study this framework,we used quality control of honeysuckle flower (Lonicerae japonicae Flos) including diploid and tetraploid Lonicera japonica,and wild honeysuckle flower (Lonicerae Flos) including Lonicerae hypoglauca,Lonicerae confusa,Lonicerae fulvotomentosa and Lonicerae macranthoides as an example.Methods:A total of 360 samples were analyzed from three variables including species,growing areas,and optimization of processing methods.For quantitative analysis,chlorogenic acid (CA),isochlorogenic acid A (3,5-DCA),and isochlorogenic acid C (4,5-DCA) were measured with high performance liquid chromatography (HPLC).Results:The three organic acids contents are higher in wild honeysuckle flower than honeysuckle flower;L.japonica (tetraploid) is higher than L.japonica (diploid).Modern processing methods (kill-enzyme torrefaction and fixing machine drying) are popular in growing areas and are superior to traditional methods (sun and shade drying).Conclusions:Novel process analysis concepts in processing analytical technology (PAT) enriched the Chinese MateHal Medica contents. 展开更多
关键词 HONEYSUCKLE FLOWER WILD HONEYSUCKLE FLOWER processing ANALYTICAL technology Quality control processing method
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常压盐溶液法制备α-半水石膏的工艺参数研究 被引量:13
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作者 李林 李琳 孙元喜 《湖南文理学院学报(自然科学版)》 CAS 2005年第1期31-33,共3页
二水石膏在盐介质中部分脱水可制得高强度α-半水石膏.采用单因素实验考察了媒晶剂、盐介质、洗涤水温度、产品干燥温度、产品粒度等因素对常压盐溶液法制备α-半水石膏的抗压强度的影响,实验结果表明:当媒晶剂为柠檬酸钠与Al3 + 等的... 二水石膏在盐介质中部分脱水可制得高强度α-半水石膏.采用单因素实验考察了媒晶剂、盐介质、洗涤水温度、产品干燥温度、产品粒度等因素对常压盐溶液法制备α-半水石膏的抗压强度的影响,实验结果表明:当媒晶剂为柠檬酸钠与Al3 + 等的复合物(占盐溶液的质量百分比为1.0 % )、盐介质为15 % (质量百分比)的KCl水溶液、洗涤水温度在98℃以上、产品干燥温度为110 - 130℃、产品粒度控制在7- 4 μm时,产品抗压强度可达4 4MPa . 展开更多
关键词 Α- AL^3%PLUS% KCl
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基于组合评价方法的绿色性焊接工艺规划评价研究 被引量:5
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作者 张华 马达 +1 位作者 肖明 江志刚 《机械设计与制造》 北大核心 2010年第12期258-260,共3页
结合焊接工艺的特点,确立由时间T、质量Q、成本C、资源消耗R、环境影响E五个方面构成的绿色性焊接工艺规划评价指标体系,并在此基础上,建立一种将熵权法、模糊评价法分别作用于评价过程中各个阶段的组合评价方法,该方法能较好地避免评... 结合焊接工艺的特点,确立由时间T、质量Q、成本C、资源消耗R、环境影响E五个方面构成的绿色性焊接工艺规划评价指标体系,并在此基础上,建立一种将熵权法、模糊评价法分别作用于评价过程中各个阶段的组合评价方法,该方法能较好地避免评价过程中的主观性和不确定性,最后通过实例验证该方法的科学性和可行性。 展开更多
关键词 绿 PROCESS PLANNING green method of
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线性随机系统振动模态参数变异规律的研究 被引量:5
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作者 苏荣华 梁冰 +1 位作者 王婷 裴忠强 《应用基础与工程科学学报》 EI CSCD 2005年第2期207-215,共9页
采用MonteCarlo随机有限元方法,对多自由度线性振动系统中由于结构参数的随机变异而引起的模态参数(模态频率、模态振型和模态阻尼比)变异的规律进行了研究.文中首次提出了相对均差系数的概念,应用相对均差系数和变异系数这两个无量纲量... 采用MonteCarlo随机有限元方法,对多自由度线性振动系统中由于结构参数的随机变异而引起的模态参数(模态频率、模态振型和模态阻尼比)变异的规律进行了研究.文中首次提出了相对均差系数的概念,应用相对均差系数和变异系数这两个无量纲量,从不同角度定量分析随机系统模态参数的变异性.数值试验结果表明,对于小阻尼比例模型,随着结构参数变异性的增大,系统模态频率均值单调变化,较低阶模态频率均值单调减小,高阶模态频率均值单调增加;模态阻尼比均值单调增加;第一阶模态振型相对均值系统的变化很小.一般地,结构参数的随机变异对模态振型均值的影响大于对模态频率、模态阻尼比均值的影响. 展开更多
关键词 线 Carlo
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Research and application of sidewall stability predic-tion method based on analytic hierarchy process and fuzzy integrative evaluation method 被引量:2
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作者 Bin Liu Fanjun Kong 《Natural Science》 2012年第2期142-147,共6页
As a difficult problem, sidewall instability has been beset drilling workers all the time. Not only does it cause huge economic losses, but also it determines the success or failure of drilling engineering. Due to com... As a difficult problem, sidewall instability has been beset drilling workers all the time. Not only does it cause huge economic losses, but also it determines the success or failure of drilling engineering. Due to complex relationship between various factors which influence sidewall stability, it hasn’t been found a widely applied method to predicate sidewall stability so far. Therefore, in order to formulate corresponding measures to ensure successful drilling, searching for a kind of better method to forecast sidewall stability before drilling becomes an imperative and significant topic for drilling engineering. On the basis of traditional sidewall stability analytical method, we have put forward the Fuzzy Comprehensive Evaluation Method to forecast sidewall stability regulation using physico-chemical performance parameters of the clay mineral. This method has been improved by introducing the Analytic Hierarchy Process (AHP) and the Maximum Subjection Principle in the application process. After introducing Analytic Hierarchy Process to identify weight, and Maximum Subjection Principle to obtain evaluation results, it has reduced the influence of human factors and enhanced the accuracy of the fuzzy evaluation results. The application in Hailaer Area indicates that this method can predict sidewall stability of gas-oil well with high credibility and strong practicability. 展开更多
关键词 Instability of SIDEWALL Forecast Fuzzy INTEGRATIVE Evaluation method ANALYTIC HIERARCHY Process Maximum SUBJECTION Principle
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Landfill Site Selection Using GIS and Multi-Criteria Decision-Making AHP and SAW Methods: A Case Study in Sulaimaniyah Governorate, Iraq
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作者 Karwan Alkaradaghi Salahalddin S. Ali +1 位作者 Nadhir Al-Ansari Jan Laue 《Engineering(科研)》 2020年第4期254-268,共15页
Lack of land for waste disposal is one of the main problems facing urban areas in developing countries. The Sulaimaniyah Governorate, located in northern Iraq, is one of the main cities of the country in the Kurdistan... Lack of land for waste disposal is one of the main problems facing urban areas in developing countries. The Sulaimaniyah Governorate, located in northern Iraq, is one of the main cities of the country in the Kurdistan Region, covering an area of 2400 km2. Currently, there is no landfill site in the study region that meets scientific and environmental requirements, inappropriate dumping of solid waste causes adverse effects on the environment, economic and urban aesthetic. To overcome with this phenomenon, it is very crucial to suggest a landfill site, even in countries that recycle or burn their waste to protect the environment. Landfill sites should be carefully selected by considering all regulations and other restrictions. The integration of geographic information systems and multi-criteria decision analysis is used in this study to select suitable landfill locations in the region, for this purpose, thirteen layers are prepared according to their importance including urban area, villages, rivers, groundwater depth, slope, elevation, soil types, geological formations, roads, oil and gas field, land use classification, archaeological site and power lines. Two different methods (simple additive weighting and analytic hierarchy process) are implemented in a geographical information system to obtain the suitability index map for candidate landfill sites, where all these sites satisfied the scientific and environmental criteria which were adopted in this study. The comparison of the maps resulting from these two different methods demonstrates that both methods produced consistent results. 展开更多
关键词 LANDFILL Site Criteria WEIGHTS GIS Software ANALYTIC Hierarchy Process (AHP) Simple Additive Weighting (SAW) method
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基于方向微分的运动模糊方向鉴别 被引量:41
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作者 陈前荣 陆启生 成礼智 《中国图象图形学报(A辑)》 CSCD 北大核心 2005年第5期590-595,共6页
在曝光的瞬间,造成图像模糊的被摄景物与相机的相对运动,虽可近似作为直线运动来处理,但模糊图像中的运动模糊方向未知。若能由模糊图像出发,估计出运动模糊方向,则可以通过图像旋转将运动模糊方向旋转到水平轴,这样图像恢复就可由2维... 在曝光的瞬间,造成图像模糊的被摄景物与相机的相对运动,虽可近似作为直线运动来处理,但模糊图像中的运动模糊方向未知。若能由模糊图像出发,估计出运动模糊方向,则可以通过图像旋转将运动模糊方向旋转到水平轴,这样图像恢复就可由2维问题转化为1维问题,这就大大降低了图像恢复的难度,并为图像恢复的并行计算创造了有利条件。为实现这一目的,将原图像看作是各向同性的一阶马尔科夫过程,提出了一种新的基于方向微分的运动模糊方向鉴别方法,该方法不仅可以高精度鉴别匀速运动、加速运动、振动等各种运动的模糊方向,而且具有鉴别范围大、鉴别精度高、稳定性好的优点。另外,为了具体实现这种鉴别,还给出了采用双线性插值或三次C样条插值进行方向鉴别的详细计算方法,其中双线性插值方法计算量小,但三次C样条插值方法的鉴别精度比双线性插值方法高,而且通过加权平均,还可进一步降低各种随机因素引起的鉴别误差,这不仅提高了鉴别精度,而且增强了运动模糊方向鉴别的稳定性,因此能够更加有效地进行方向鉴别。 展开更多
关键词 线 线
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制备工艺对氧化铝包裹铝复合材料性能的影响 被引量:2
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作者 卢红霞 陈昌平 +2 位作者 杨会智 孙洪巍 胡行 《中国陶瓷工业》 CAS 2005年第3期8-11,共4页
采用非匀相沉淀法和常压烧结的方法制备出了Al2O3包裹Al复合陶瓷。研究了起始Al(NO3)3浓度、氨水滴定速度、反应体系pH值以及煅烧温度等工艺条件对包裹粉体性能的影响,同时对Al2O3/Al复合陶瓷的微观结构和性能进行了研究。结果表明,Al(N... 采用非匀相沉淀法和常压烧结的方法制备出了Al2O3包裹Al复合陶瓷。研究了起始Al(NO3)3浓度、氨水滴定速度、反应体系pH值以及煅烧温度等工艺条件对包裹粉体性能的影响,同时对Al2O3/Al复合陶瓷的微观结构和性能进行了研究。结果表明,Al(NO3)3溶液浓度控制在0.2mol/L,滴定速度为25ml/min,反应体系pH值为8 ̄9时可以获得团聚少、分散性好的Al(OH)3包裹Al粉体,α-Al2O3的转变温度降至1000°C左右。Al2O3/Al复合陶瓷结构致密,包裹层中的Al2O3为500nm左右,复合材料的断裂韧性有显著提高。 展开更多
关键词 Α-AL2O3 pH min
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Autofocus technique for ISAR imaging of uniformly rotating targets based on the ExCoV method 被引量:1
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作者 Chengguang Wu Hongqiang Wang +2 位作者 Bin Deng Yuliang Qin Wuge Su 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第2期267-275,共9页
The inverse synthetic aperture radar (ISAR) imaging can be converted into a sparse reconstruction problem and solved by the l1norm minimization algorithm. The basis matrix in sparse ISAR imaging is usually characteriz... The inverse synthetic aperture radar (ISAR) imaging can be converted into a sparse reconstruction problem and solved by the l1norm minimization algorithm. The basis matrix in sparse ISAR imaging is usually characterized by the unknown rotation rate of a moving target, thus the rotation rate and the sparse signal should be jointly estimated. Especially due to the imperfect coarse motion compensation, we consider the phase error correction problem in the context of the sparse signal reconstruction. To address this issue, we propose an iterative reweighted method, which jointly estimates the rotation rate, corrects the phase error and reconstructs a high resolution ISAR image. The proposed method gives a gradual and interweaved iterative process to refine the unknown parameters to achieve the best sparse representation for the ISAR signals. Particularly, in ISAR image reconstruction, the l1norm minimization algorithm is sensitive to user parameters. Setting these user parameters are not trivial and the reconstruction performance depends significantly on their choices. Then, we consider an expansion-compression variance-component (ExCoV) based method, which is automatic and demands no prior knowledge about signal-sparsity or measurement-noise levels. Both numerical and electromagnetic data experiments are implemented to show the effectiveness of the proposed method. It is shown that the proposed method can estimate the rotation rate and correct the phase errors simultaneously, and its superior performance is proved in terms of high resolution ISAR image. © 2017 Beijing Institute of Aerospace Information. 展开更多
关键词 Error compensation Error correction Errors Image processing Image reconstruction Inverse problems Inverse synthetic aperture radar Iterative methods Motion compensation Numerical methods Rotation Signal reconstruction Synthetic aperture radar
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结构可靠度分析的高斯过程重要抽样方法 被引量:1
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作者 肖义龙 苏国韶 《水力发电》 北大核心 2010年第12期31-33,50,共4页
针对传统复杂水工结构可靠度分析方法的局限性,提出了结构可靠度分析的高斯过程重要抽样方法。通过高斯过程机器学习方法实现结构功能函数及其偏导数的显式表达,进而结合传统重要抽样法计算结构的失效概率与可靠指标。实例验证了方法的... 针对传统复杂水工结构可靠度分析方法的局限性,提出了结构可靠度分析的高斯过程重要抽样方法。通过高斯过程机器学习方法实现结构功能函数及其偏导数的显式表达,进而结合传统重要抽样法计算结构的失效概率与可靠指标。实例验证了方法的可行性,与传统方法相比较,高斯过程重要抽样方法具有计算精度高、计算效率高和参数自适应化等优点。 展开更多
关键词 Reliability Analysis Sampling method
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Analysis of DAR(1)/D/s Queue with Quasi-Negative Binomial-II as Marginal Distribution
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作者 Kanichukattu Korakutty Jose Bindu Abraham 《Applied Mathematics》 2011年第9期1159-1169,共11页
In this paper we consider the arrival process of a multiserver queue governed by a discrete autoregressive process of order 1 [DAR(1)] with Quasi-Negative Binomial Distribution-II as the marginal distribution. This di... In this paper we consider the arrival process of a multiserver queue governed by a discrete autoregressive process of order 1 [DAR(1)] with Quasi-Negative Binomial Distribution-II as the marginal distribution. This discrete time multiserver queueing system with autoregressive arrivals is more suitable for modeling the Asynchronous Transfer Mode(ATM) multiplexer queue with Variable Bit Rate (VBR) coded teleconference traffic. DAR(1) is described by a few parameters and it is easy to match the probability distribution and the decay rate of the autocorrelation function with those of measured real traffic. For this queueing system we obtained the stationary distribution of the system size and the waiting time distribution of an arbitrary packet with the help of matrix analytic methods and the theory of Markov regenerative processes. Also we consider negative binomial distribution, generalized Poisson distribution, Borel-Tanner distribution defined by Frank and Melvin(1960) and zero truncated generalized Poisson distribution as the special cases of Quasi-Negative Binomial Distribution-II. Finally, we developed computer programmes for the simulation and empirical study of the effect of autocorrelation function of input traffic on the stationary distribution of the system size as well as waiting time of an arbitrary packet. The model is applied to a real data of number of customers waiting for checkout in an airport and it is established that the model well suits this data. 展开更多
关键词 Discrete Autoregressive PROCESS of Order [DAR(1)] Multiserver ATM Multiplexer Matrix Analytic methods MARKOV Renewal PROCESS MARKOV Regenerative Theory Teleconference Traffic Quasi-Negative Binomial Distribution-II Generalized Poisson DISTRIBUTION Borel-Tanner DISTRIBUTION
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Cognitive Control and Brain Network Dynamics during Word Generation Tasks Predicted Using a Novel Event-Related Deep Brain Activity Method
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作者 Emiko Imai Yoshitada Katagiri 《Journal of Behavioral and Brain Science》 2018年第2期93-115,共23页
There is a growing interest in the diagnosis and treatment of patients with dementia and cognitive impairment at an early stage. Recent imaging studies have explored neural mechanisms underlying cognitive dysfunction ... There is a growing interest in the diagnosis and treatment of patients with dementia and cognitive impairment at an early stage. Recent imaging studies have explored neural mechanisms underlying cognitive dysfunction based on brain network architecture and functioning. The dorsal anterior cingulate cortex (dACC) is thought to regulate large-scale intrinsic brain networks, and plays a primary role in cognitive processing with the anterior insular cortex (aIC), thus providing salience functions. Although neural mechanisms have been elucidated at the connectivity level by imaging studies, their understanding at the activity level still remains unclear because of limited time-based resolution of conventional imaging techniques. In this study, we investigated temporal activity of the dACC during word (verb) generation tasks based on our newly developed event-related deep brain activity (ER-DBA) method using occipital electroencephalogram (EEG) alpha-2 powers with a time resolution of a few hundred milliseconds. The dACC exhibited dip-like temporal waveforms indicating deactivation in an initial stage of each trial when appropriate verbs were successfully generated. By contrast, monotonous increase was observed for incorrect responses and a decrease was detected for no responses. The dip depth was correlated with the percentage of success. Additionally, the dip depth linearly increased with increasing slow component of the DBA index at rest across all subjects. These findings suggest that dACC deactivation is essential for cognitive processing, whereas its activation is required for goal-oriented behavioral outputs, such as cued speech. Such dACC functioning, represented by the dip depth, is supported by the activity of the upper brainstem region including monoaminergic neural systems. 展开更多
关键词 DEEP BRAIN ACTIVITY Alpha-2 Wave Cognitive processing Dorsal Anterior CINGULATE Cortex EVENT-RELATED DEEP BRAIN ACTIVITY method
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