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101.
Taiju Takahashi Yukihiro Kudoh Yuichi Saito Yoshihiro Aoyagi 《Journal of the Society for Information Display》2023,31(3):101-111
Recently, there has been considerable research on optical devices, such as liquid crystal (LC) lenses and special optical plates, using LCs. In such devices, relatively small LC cells are frequently used, or unique LC orientations are required. As an LC orientation process, we focused on the LC director's orientation induced by the magnetic force line distribution of a small neodymium magnet. We propose a simple method for obtaining radial orientation, which is rather difficult to obtain using the ordinary rubbing method. The initial orientation in the LC cell is a vertical orientation cell with almost zero azimuth anchoring. With the proposed method, the reorientation process is performed with an assisting electric field and a small permanent magnet, unlike the conventional magnetic field orientation process that requires a large electromagnet. Furthermore, a polymer stabilization treatment is used to fix the obtained radial orientation pattern in the LC cell. After the treatment, the applying voltage can control the tilt angle of the director in weak polymer treatment, and a completely fixed orientation pattern can be obtained that in strong. 相似文献
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104.
Nucleation Crystallography of Ni Grains on CrFeNb Inoculants Investigated by Edge‐to‐Edge Matching Model in an IN718 Superalloy 下载免费PDF全文
Wenchao Yang Pengfei Qu Lin Liu Ziqi Jie Taiwen Huang Feng Wang Jun Zhang 《Advanced Engineering Materials》2018,20(2)
105.
基于情感词典扩展技术的网络舆情倾向性分析 总被引:7,自引:0,他引:7
随着Web2.0时代的到来,网络已逐渐成为反映社会舆情的重要载体之一,网络舆情发现及网民的观点和倾向性挖掘也成为新的研究热点,但是目前尚无有效反应网民对热点事件或话题总体态度的舆情分析系统.本文针对网民关于话题评论简单、数目众多的特点,应用HowNet和NTUSD两种资源对现有情感词典进行扩展,建立了一个新的、具有倾向程度的情感词典.基于扩展的情感词典,开发了一个半自动化网络舆情分析系统.该系统能够为用户提供更加细致、准确的评论倾向性分析结果. 相似文献
106.
This paper discusses the benefits of applying Augmented Reality (AR) to facilitate intuitive robot programming, and presents a novel methodology for planning collision-free paths for an n degree-of-freedom (DOF) manipulator in an unknown environment. The targeted applications are where the end-effector is constrained to move along a visible 3D path/curve, which position is unknown, at a particular orientation with respect to the path, such as arc welding and laser cutting. The methodology is interactive as the human is involved in obtaining the 3D data points of the desired curve to be followed through performing a number of demonstrations, defining the free space relevant to the task, and planning the orientations of the end-effector along the curve. A Piecewise Linear Parameterization (PLP) algorithm is used to parameterize the data points using an interactively generated piecewise linear approximation of the desired curve. A curve learning method based on Bayesian neural networks and reparameterization is used to learn and generate 3D parametric curves from the parameterized data points. Finally, the orientation of the end-effector along the learnt curve is planned with the aid of AR. Two case studies are presented and discussed. 相似文献
107.
当前,随着环境问题的日益突出,要求加强对环境的保护、修复和美化已成为人们实践活动中的一个关键内容,而与解决环境问题紧密相关的环境艺术设计更是责任重大,尤其是在资源型城市(如矿山、油田、旅游区等),要尝试探索如何充分理解自然生态系统运行规律和自然美学价值,宏观地赋予环境艺术设计新的内涵和价值,在功能、形式、生态、经济和人文诸多因素中谋求环境与人的平衡。 相似文献
108.
In a rapidly changing IT environment, IT professionals need to keep abreast of technological knowledge. We examined how well this is achieved by developing a motivational model of “technological knowledge renewal effectiveness.” We hypothesized that (1) renewal effectiveness was influenced by the IT professional's career orientation, perceived IT dynamism, tolerance of ambiguity, delegation; and (2) that this positively affected both intrinsic and extrinsic job satisfaction. Survey data from 126 IT professionals was used to test the hypotheses. The results generally supported the research model. We discussed the implications of these results in both research and practice. 相似文献
109.
This paper presents a model which predicts the part orientation error tolerance of a three-fingered robotic gripper. The concept of “self-alignment” is introduced, where the gripper uses the grasping process to bring the workpiece into its final state of orientation. The gripper and part are represented mathematically, and initial contact locations upon grasp closure determined. This information is used to solve for the contact forces present, and criteria are developed to determine if beneficial part motion resulting in self-alignment is expected. The results are visualized via a boundary projected on a reference plane below the part. The model is validated experimentally with a number of part configurations with favorable results. This method presents a useful tool by which the mechanical designer can quantitatively predict the performance of an intuitively designed gripping system. 相似文献
110.