• Proceedings of the Korean Geotechical Society Conference
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.976-984
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• 2009

This study proposes a simple method that uses a simple mass-spring model to predict the natural frequency of a soil-pile-structure system in sandy soil. This model includes a pair of matrixes, i.e., a mass matrix and a stiffness matrix. The mass matrix is comprised of the masses of the pile and superstructure, and the stiffness matrix is comprised of the stiffness of the pile and the spring coefficients between the pile and soil. The key issue in the evaluation of the natural frequency of a soil-pile system is the determination of the spring coefficient between the pile and soil. To determine the reasonable spring coefficient, subgrade reaction modulus, nonlinear p-y curves and elastic modulus of the soil were utilized. The location of the spring was also varied with consideration of the infinite depth of the pile. The natural frequencies calculated by using the mass-spring model were compared with those obtained from 1-g shaking table model pile tests. The comparison showed that the calculated natural frequencies match well with the results of the 1-g shaking table tests within the range of computational error when the three springs, whose coefficients were calculated using Reese's(1974) subgrade reaction modulus and Yang's (2009) dynamic p-y backbone curves, were located above the infinite depth of the pile.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 한국퍼지및지능시스템학회 2001년도 추계학술대회 학술발표 논문집
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• pp.95-98
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• 2001

In this paper, we propose a method how to determine the medical section select that get input the conditions of illness from a dialog-box using a fuzzy logic as a guidance system of the Cyber Hospital. It is to offer an output the most matched section for medical treatment using the Algebraic product fuzzy inference and Max inference after match the membership degree table of symptoms of received input from patient and their information. It will present of the direction for ignored patient which of a medical section select.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.1033-1037
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• 1997

In the end milling process, the information of axial and depths of cut plays an important role in adaptive control systems for precision machining and tool monitoring systems for unmanned machining. In general, it is not easy to know the depths of cut due to irregular shape of workpieces, inaccurate positioning of them on the table of machine tool and machining error in previous cutting. In addition to, even they are informed, it is difficult to match the individual position of the cutter on the varying shape of the work material. This work suggest an algorithm estimating the depths of cut based on cutting force sigal. The proposed algorithm can be applied in more extensive cutting situations, for example, presence of the tool wear, variation of work material hardness, etc.

• Journal of the Korean Institute of Telematics and Electronics A
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• 제30A권9호
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• pp.14-23
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• 1993

In this paper, we present analysis results of various intermodulation products (IMPs) evaluation methods previously proposed for nonlinear systems. The results indicate that out of these methods, Fuenzalida and Simbo's method is the best for efficient evaluation of IMPs. Also, we present a detailed mathematical analysis of IMP and show how to apply the equations related to IMP to actual program implementations with examples. In this paper, we newly introduce three methods to reduce the IMP calculation time and improve the accuracy of the outputs :1) TWTA curve fitting method by LS (Least Square), 2) IMP evaluation technique which is based on a look-up table 3) Gaussian spectral shaping for PSK signal instead of convolution. The IMP evaluation results obtained by the new approaches introduced in this paper resulted in a good match with the published outputs in the open literature and showed improved performance especially in the TWTA curve .

• The Journal of Korean Institute of Communications and Information Sciences
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• 제22권7호
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• pp.1403-1410
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• 1997

Because streaming mode connection server suitable to wide area ATM networks performs transmission, reception and lookup with time restriction for the transmission time of a cell, it has demerits of large cell loss incase that burst traffic occurs. Therefore, in this paper to decrease cell loss we propose a high speed CAM (Content Addressable Memory) which is capable of processing data of streaming mode connections server at a high speed. the proposed CAM is applied to forwarding table VPC map which performs function to output connection numbers about input VPI(Virtual Path Identifier)/VCI(Virtual Channel Identifier). The designed high speed CAM consist of DBL(Dual Bit Line) CAM structure performed independently write operation and match operation and two-port SRAM structure. Also, its simulation verification and full-custom layout is performed by Hspice and Composs tools in 0.8 .$\mu$m design rule.

• Proceedings of the Korean Information Science Society Conference
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• 한국정보과학회 2004년도 가을 학술발표논문집 Vol.31 No.2 (3)
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• pp.550-552
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• 2004

분산 해시 테이블 (Distributed Hash Table) 을 사용한 P2P 시스템에서는 해시함수를 사용하며 파일과 노드의 ID를 정의하고 파일의 ID와 매핑 (mapping) 되는 ID를 가진 노드에 파일을 저장함으로써 시스템 전체에 파일을 완전히 분산시킨다. 이러한 시스템에서는 파일을 찾을 때 해시된 파일 ID로 찾기 때문에 정확한 매치 (exact match) 만 가능하다. 하지만 현재 P2P 파일 공유 시스템에서는 파일의 전체 이름을 정확히 알지 못하더라도 부분적인 키워드로 파일을 검색할 수 있도록 하는 키워드 검색 (keyword search) 이 요구된다. 본 논문에서는 분산 해시 테이블을 기반으로 하는 P2P 시스템에서 키워드 검색이 가능하도록 하는 방안을 제안한다.

• International Journal of Control, Automation, and Systems
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• 제3권1호
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• pp.56-69
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• 2005

In this paper, it is clearly shown that the two well-known necessary and sufficient conditions mp n as generic static output feedback pole-assignment and mp + d(m+p) n+d as generic minimum d-th order dynamic output feedback pole-assignment on complex field, unbelievably, do not match up each other in strictly proper linear systems. For the analysis, a diagram analysis is newly created (which is defined by the analysis of 'convoluted rectangular/dot diagrams' constructed via node-branch conversion of the signal flow graphs of output feedback gain loops). Under this diagram analysis, it is proved that the minimum d-th order dynamic output feedback compensator for pole-assignment in m-input, p-output, n-th order systems is quantitatively decomposed into static output feedback compensator and its associated d number of arbitrary 1st order dynamic elements in augmented (m+d)-input, (p+d)-output, (n+d)-th order systems. Total configuration of the mismatched data is presented in a Table.

• Journal of the Institute of Electronics and Information Engineers
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• 제49권11호
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• pp.74-85
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• 2012

In this paper, we propose a optical property correction technique for a low-cost heterogeneous stereoscopic camera. Three main optical properties of a stereoscopic camera are zoom, focus, and DOF(depth of field). The difference or mis-match of these properties between two stereoscopic videos are the main causes of the visual fatigue to human eyes. The proposed correction technique reduces the difference of the optical properties between the stereoscopic videos and produces high-quality stereoscopic videos. To correct the zoom difference, a LUT(look-up table) is established to match the zoom ratio between the stereoscopic videos. To correct the DOF difference, the magnitude of image edge is measured and the lens iris is changed to control the DOF of the camera. A vertical-type stereoscopic rig is developed for the experiments of the optical property correction. Based on the experimental results, we find that a low-cost heterogeneous stereoscopic camera can be implemented, which can yield low visual fatigue to human eyes.

• Earthquakes and Structures
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• 제19권2호
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• pp.129-144
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• 2020

In this study, the idea of damping force linearly proportional to horizontal isolation displacement is implemented into sloped rolling-type bearings in order to meet different seismic performance goals. In addition to experimentally demonstrating its practical feasibility, the previously developed analytical model is further modified to be capable of accurately predicting its hysteretic behavior. The numerical predictions by using the modified analytical model present a good match of the shaking table test results. Afterward, several sloped rolling-type bearings designed with linearly variable damping force are numerically compared with a bearing designed with conventional constant damping force. The initial friction damping force adopted in the former is designed to be smaller than the constant one adopted in the latter. The numerical comparison results indicate that when the horizontal isolation displacement does not exceed the designed turning point (or practically when subjected to minor or frequent earthquakes that seldom have a great displacement demand for seismic isolation), the linearly variable damping force design can exhibit a better acceleration control performance than the constant damping force design. In addition, the former, in general, advantages the re-centering performance over the latter. However, the maximum horizontal displacement response of the linearly variable damping force design, in general, is larger than that of the constant damping force design. It is particularly true when undergoing a horizontal isolation displacement response smaller than the designed turning point and designing a smaller value of initial friction damping force.

• The Journal of Sustainable Design and Educational Environment Research
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• 제19권1호
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• pp.13-24
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• 2020

The purpose of this study is to analyze and match future teaching-learning methods with learning-space types as customized not only by school grade or grade groups, but also by learning modality. As a result, the following six teaching-learning methods were identified as future teaching-learning methods: flipped learning, deeper learning, collaborative learning, learning through immersive virtual reality, playful learning, and learning through OER(Open Educational Resources). There were also six learning-space types that were identified: playing and discovering space, a making and placement space, a presentation and sharing space, a space for independent study, space as a stage, and space as content(See Tables 8 and 11). Learning-space types and future teaching-learning methods were matched with 22 different types of learning modalities based on the presented degree of utilization by school grade or grade groups(See Table 13).