This paper develops a design technique for approximating nonseparable frequency characteristics by sums and products of separable transfer functions. Therefore nonseparable frequency characteristics includes the four-quadrant symmetry filters. The desired filter with half plan symmetry is obtained by shifting a low pass characteristic in the frequency domain, and by combining these shifted characteristics. Also the paper develops the technique for designing recursive and nonrecursive two dimensional digital filters by the application of a complex transformation to one dimensional low pass filter.

일반적으로 2차원 Poisson 방정식을 풀기 위해 유한 차분법을 이용하여 tridiagonal block Toeplitz 선형방정식을 얻는다. 이 선형방정식의 독특한 형태를 활용하기 위해 Lyapunov 방정식으로 변화시킨 다음 이산정현변환(DST)을 이용해서 대각선 행렬로 만들면 계산이 용이해진다. 또 DST는 FFT를 이용해 계산할 수 있으므로 고속 계산이 가능하다. FFT를 병렬로 처리하기 위해 프로세서가 4,096개인 SIMD 컴퓨터 MP-2에서 시뮬레이션했다. 본 논문에서는 알고리즘 유도, 매핑 및 시뮬레이션 결과를 제시했다.

Neighborhood living boundary plan is offerd amenity living environment to inhabitants. This plan is contained that district unit division, appropriate living facilities disposition, and that one of the urban elementary plan in city political activities. The theme is on the primary School attendanced area in chun-cheon city, and analysis school attendanced area as an administrative district.

Up to the present the study on the performance prediction of HAWT was perfomed mainly by assuming the axial flow. So in this paper we aimed at the fully non-axial flow of HAWT. For this purpose, we defined the wind turbine pitch angle in addition to the yaw angle to specify the arbitrary wind direction. And we adopted the Glauert method as the basic analysis method then modified this method suitably for our goal. By comparing the computational results obtained by this modified new Glaurert method with the experimental results, it was proved that our method was a very efficient method.

This study deals with the automated storage/retrieval systems (AS/RS) where the rack is discrete and the random storage assignment rule is adopted. New storage policies named FNSC (first no-cost zone, second closest-open location) and FNSH (first no-cost zone, second a half side closest-open location) are proposed. Simulation results indicate that performance of FNSH is slightly lower than that of the SCL but it does not need much time to perform. The "stay" strategy of S/R machine is examined as a means of increasing the frequency of dual command.

The objective of this research is to analyze the phenomena of negative ion behavior in silane plasma chemical vapor deposition. Based on the plasma chemistry, the model equations for the formation and transport of negative ions were proposed and solved. The evolutions of gaseous species along the reactor were presented for several conditions of process variables such as reactor pressure, total gas flow rate, and electric field. Based on the model results, it is found that : (1) The concentration profiles of positive ions show the sharp peaks at the center of plasma reactor. (2) Most of negative ions are located in bulk plasma region, because the negative ions are excluded from the sheath region by electrostatic repulsion.

This research is an experimental work of investigating the behavior of soil nailing system under surcharges whereas most of them were concentrated on evaluating its capacity under selfweight of excavated ground. Model tests in laboratory were performed to investigate the ultimate bearing capacity of soil nailing system under surcharges in forms of strip loading. Tests were carried out to find parameters controlling its capacity such as length of nail, vertical and horizontal spacings between nails, inclination of nail installation, and loading position of surcharges. Failure mechanism of forming failure line due to surcharge to soil nailing system was also observed by using dyed sand and monitoring its behavior. From results of these test, effects of parameters was analyzed qualitatively. Thus, this experimental results could provide meaningful data to analyze and design this system later.

The effects of transient inrush currents on the dynamic characteristics of percentage differential relays are studied when the power transformers are reenergized. An algorithm of estimation the nonlinear magnetic property of power transformer and current trnasformer core are developed. Using this method, we can analyze the effect of inrush currents on the trip region of the percentage differential relays corresponding to the variation of the phase angle and the residual magnetism at the instant of switch closing. Test results are used to verify the availibility of the proposed algorithm. Finally a case study is performed to the 110 MVA main transformer in hydraulic power station.

This study is to investigate harbor oscillation phenomenon according to combination of the wall structures by model experiment in a three dimensional wave basin. Six different types of wall combination were chosen through combination of erect wall, erect dissipation block, and sand beach, wave height at selected points in the harbor were measured by electronic wave gage. Test results show that the wall structure composed solely of erect walls showed generally highest harbor oscillation. Since natural beach shows lower reflection than erect dissipation block do, we thought it would be more efficient to use natural beach for improved harbor oscillation. The result showed, however, that the erect dissipation block are more efficient than natural beach to attain less harbor oscillation. The reason seens that the erect dissipation blocks have better capability to control breaking wave on the surface of the structure.

To satisfy the requirement for the precision and productivity of machine tools, we need the technique to predict the surface roughness of workpiece under various cutting conditions. The surface roughness is mainly influenced by the ideal roughness i. e., the roughness by feeding quantity and geometry of the tool. In this paper, the surface roughness is divided into three zones and the mathematical models of the three zones are obtained, in consideration of the feeding conditions and tool geometry. Using the mathematical models, we developed a program to calculate the maximum feeding quantity satisfying the required surface roughness of the workpiece. The program is used to calculate the maximum feed for two kinds of the bites used under the real cutting condition.

Ultra-precision machine tool equipped with the diamond bite tip is used to machine optical products, drums of VTR or computer hard disk. It needs nano technology in the surface roughness of workpiece. To perform the nano scale machining, ultra-precision machine tool must be designed and manufactured in consideration of the vibration characteristics. In this paper, using the finite element analysis, we investigate the modal parameters of the ultra-precision machine tool structures, which use cast iron, granite and alumina ceramic for the bed materials. To verify the numerical results, we manufacture a model of ultra-precision machine tool using granite bed and perform impulse test. Through the theoretical and experimental analyses, we could compare and estimate the vibration characteristics of the three models for the ultra-precision machine tools.

This study is concerned with the accuracy and the patterns when different methods was used in interpolation task. Although 3 methods employed the same modality for input (visual) and for output (manual responding), they differed in central processing, which method 1 is relatively more tendency of verbal processing, method 2 is realtively more tendency of spatial processing and method 3 needed a number of switching code (verbal/spatial) performing task. Split-plot design was adopted, which whole plot consisted of methods (3), orientations (horizon, vertical), base-line sizes (300, 500, 700 pixels) and split plot consisted of target locations (1-99). The results showed the anchor effect and the range effect. Method 2, method 3 and method 1 that order was better accuracy. ANOVA showed that the accuracy was significantly influenced by the method, the location of target, and its interactions ($method{\times}location$, $size{\times}location$). Analysis of error data, response time and frequency of under, just, over estimate indicated that a systematic error pattern was made in task and methods changed not only the performance but also the pattern. The results provided support for the importance of the multiple resources theory in accounting for S-C-R compatibility and task performance. They are discussed in terms of multiple resources theory and guidelines for system design is suggested by the S-C-R compatibility.

폴리이미드 분리막에 의한 $CCl_2F_2/Air$ 혼합물의 분리특성에 관하여 온도, 압력, stage cut(${\theta}$), 주입기체 조성등의 영향을 규명하였다. 본 연구의 실험범위 내에서 이상분리인자(ideal separation factor)는 600-200이었으며, glassy polymer인 폴리이미드 분리막에 대하여 투과도가 높은 air의 투과도는 $CCl_2F_2$ (dichlorodifluoromethane, CFC-12)에 의하여 상당히 감소함을 알 수 있었다. 그러나, 폴리이미드 분리막에 대한 투과도가 낮은 $CCl_2F_2$의 투과도는 air에 의하여 투과도가 증가하였다. 또한, 수학적 모델에 의한 예측치가 실험치와 잘 일치됨을 알 수 있었다.