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81.
Hyo-Heon Ko Jun-Seok Kim Jihyun Kim Jun-Geol Baek Sung-Shick Kim 《Expert systems with applications》2011,38(6):6759-6767
This paper proposes an efficient control method to minimize process error and to reduce process variance in semiconductor manufacturing. The photolithography (photo) process forms a complex semiconductor circuit and is important for quality. Obstacles to the process include the facility itself, vibration, wear and tear, product/process changes and environmental influences. Control methodologies being currently used to address these issues often amplify the variation of the process by failing to perform adequate process control. Therefore, this paper proposes an effective process control method to reduce process variance by quickly detecting and identifying process disturbances and accurately reflecting the degree of change to process control. This study proposes dynamic deadband control that uses a region (band) to detect the status of a process change. It adjusts the process control based on the changes detected. In this research, the semiconductor manufacturing company is supported to perform control that is more precise and reduces fluctuations by producing products of uniform quality. In addition, it can contribute to yield due to the quality incentive and increased process control of semiconductor manufacturing. 相似文献
82.
83.
Twenty-seven subjects completed 2-min typing tasks using four typing styles: right-hand holding/typing (S-thumb) and two-hand typing at three heights (B-low, B-mid and B-high). The styles had significant effects on typing performance, neck and elbow flexion and muscle activities of the right trapezius and several muscles of the right upper limb (p < 0.0001 by repeated-measure analysis of variance). The subjects typed the fewest words (error-adjusted characters per minute: 78) with the S-thumb style. S-thumb style resulted in similar flexion angles of the neck, elbow and wrist, but significantly increased muscle activities in all tested muscles compared with the B-mid style. Holding the phone high or low reduced the flexion angles of the neck and right elbow compared with the B-mid style, but the former styles increased the muscle activity of the right trapezius. Right-hand holding/typing was not a preferable posture due to high muscle activities and slow typing speed.
Practitioner Summary: Right-hand holding/typing was not favoured, due to increased muscle activities and slower typing speed. Holding the phone high or low reduced the flexion angles of the neck and right elbow, but the former styles increased the muscle activity of the right trapezius compared with holding the phone at chest level. 相似文献
84.
Lee Jae-Gu Choi Kyung-Chan Yeon Seung-Ho Kim Jeong Won Ko Young-Woong 《Multimedia Tools and Applications》2017,76(23):25477-25494
Multimedia Tools and Applications - In digital pathology, image similarity algorithms are used to find cancer in tissue cells from medical images. However, it is very difficult to apply image... 相似文献
85.
Kwang Hee Ko Taezoon Park Kyong-Hwan Kim Yonghwan Kim Dong Ho Yoon 《Computer aided design》2011,(8):848-862
In this paper, a panel generation system for analyzing seakeeping performance of a ship is developed. Given a set of offset data representing the ship hull, the system first creates a surface model of the ship. From the surface model, the wetted part of the ship is obtained by computing the intersection between the water surface and the hull, which is then processed to generate quadrilateral panels for the hull and the water surface. The system is designed to handle various kinds of ships such as ships with a mono-skeg, a twin-skeg and/or a bulbous bow in either an automatic or an interactive manner. Moreover, it can generate input panels for three different seakeeping analysis methods. Examples are provided to demonstrate the capabilities of the system. 相似文献
86.
Rachel Edita Oñate Roxas Allan Borra Charibeth Ko Cheng Nathalie Rose Lim Ethel Chuajoy Ong Michelle Wendy Tan 《Language Resources and Evaluation》2008,42(2):183-195
In this paper, we present the building of various language resources for a multi-engine bi-directional English-Filipino Machine
Translation (MT) system. Since linguistics information on Philippine languages are available, but as of yet, the focus has
been on theoretical linguistics and little is done on the computational aspects of these languages, attempts are reported
here on the manual construction of these language resources such as the grammar, lexicon, morphological information, and the
corpora which were literally built from almost non-existent digital forms. Due to the inherent difficulties of manual construction,
we also discuss our experiments on various technologies for automatic extraction of these resources to handle the intricacies
of the Filipino language, designed with the intention of using them for the MT system. To implement the different MT engines
and to ensure the improvement of translation quality, other language tools (such as the morphological analyzer and generator,
and the part of speech tagger) were developed. 相似文献
87.
A new approach to the generation of a feature-point-driven facial animation is presented. In the proposed approach, a hypothetical face is used to control the animation of a face model. The hypothetical face is constructed by connecting some predefined facial feature points to create a net so that each facet of the net is represented by a Coon's surface. Deformation of the face model is controlled by changing the shape of the hypothetical face, which is performed by changing the locations of feature points and their tangents. Experimental results show that this hypothetical-face-based method can generate facial expressions which are visually almost identical to those of a real face. 相似文献
88.
Organ blood flow is controlled, in part, by changes in diameter of resistance vessels. In thick tissue, vessels can be imaged with a microscope using contrast-enhancing methods (e.g., fluorescence) and image analysis techniques can be used for quantitative diameter estimations. However, a change in the position of a vessel with respect to the plane of focus can be misinterpreted as a diameter change. In order to address this problem, a 3D image in a light microscope is obtained by serial optical sectioning, and a 3D deconvolution procedure (Avinash et al., 1991, "Fourteenth Association for Research in Otolaryngology Midwinter Meeting, St. Petersberg, FL," Abstract 156) is used to deblur 3D image data. Deblurred sections are computationally projected onto a 2D plane to give an extended-focus image, from which diameter estimates of microvessels are made using a quantitative, 2D diameter-tracking algorithm (Miles, 1987, "Semiautomatic Quantitative Image Analysis of Dynamic in Vivo Cochlear Microvessel Diameters." Ph.D. dissertation, Univ. Michigan; Miles and Nuttall, 1992, IEEE Trans. Biomed. Eng.). Justification for 3D preprocessing before diameter analysis is provided by absolute and relative error analyses using computer-generated synthetic vessels. The 3D diameter analysis technique is validated using a capillary tube of known diameter, filled with fluorescent solution. Demonstration of its applicability is shown in diameter measurements from the vessels of guinea pig cochlea. Our approach, using extended-focus images, minimizes overestimation of microvascular diameters and underestimation of relative diameter changes. Therefore, unambiguous diameter measurements are possible with extended-focus images. 相似文献
89.
Ker-I Ko 《Theory of Computing Systems》1985,18(1):189-205
The complexity theoretic concept of levelability is introduced to the accepting density hierarchy inNP. A setA inNP islevelable with respect to densityu(n) if for every polynomial-time nondeterministic Turing machine (NTM)M that acceptsA there is a better NTMM forA that improves the accepting density ofM infinitely often from the density belowu(n) tou(n). We investigate the structural properties of nonlevelable sets inNP. A nonlevelable set must have a maximal complexity core, and its maximal cores must have relatively low complexity. Most naturalNP-complete sets are paddable and hence levelable with respect to the two lowest levels in the accepting density hierarchy. A relativized accepting density hierarchy is constructed to demonstrate the possibility of the existence of nonlevelable sets at each level of the hierarchy.This research was supported in part by the National Science Foundation under Grants MCS-8103479 and MCS-8103479A01. 相似文献
90.
A program for the integration of chronic psychiatric patients into independent living in the community is described and data indicating its success are presented. The program is based on an educational, behavioral, social systems model, where "educational" refers directly to teaching skills which a person lacks, "behavioral" deals with providing the motivation to perform these skills and to precisely operationalize and measure the effectiveness of the steps in learning them, and "social systems" describes influencing clients' social environments in their interests. The model has wider implications for reintegrating a variety of socially marginal individuals into the mainstream of society. 相似文献