MEMS 제작기술에 관한 연구

허재헌 안양대학교 산업기술연구소 2001 自然科學硏究 Vol.8 No.-

Micromachining 기술은 bulk 가공 기술과 기판 위에 형성한 박막 등을 가공하여 원하는 형상을 제작하는 표면 가공 기술로 대변될 수 있다. Micro-Electro-Mechanical System(MEMS)가 시스템을 구현하는 미래 기술이므로, 이를 추구하기 위해서는 재료의 개발과 개선, 반도체 가공기술을 기초로 한 특수가공기술, 시스템의 설계기술, 그리고 특성평가기술을 필요로 한다. 현재 사용되고 있는 로타리 타입, cantilever 타입, membrane 타입, hinge 타입 RF Relay 스위치의 제조방법에 대하여 고찰한다. In this paper, the fabrication technologies of the RF switch using MEMS(Micro-Electro-Mechanical System) were presented. The most advanced fabrication technologies are cantilever type, membrane type, hinge type. For the future application of MEMS fabrication technologies are in the areas of the RF parts for wireless mobile communications. Further studies are needed to develop the materials, vacuum processing, and RF circuit design.

A Note on Dependence among Spacings

Kim, S. H. 안양대학교 산업기술연구소 2000 自然科學硏究 Vol.7 No.-

In this note, it will be shown that if the distribution F of X is increasing (decreasing) failure rate, then the spacings are multivariate negative (positive) dependence structure, that is, conditionally decreasing (increasing) in sequence. Numerical illustrations are given.

Residential Location Choice Model with Nonwork Trips

Cho, Kyuyoung 안양대학교 산업기술연구소 1998 自然科學硏究 Vol.5 No.2

Nonwork trips have been neglected in most urban location choice models regardless of theirs rapidly increasing portion of total trips. In this paper, several ways to incoporate nonwork trips in the residential loaction choice have been explored. Those are; 1) based on the traditional residential location model (utility maximization); 2) with fixed locations of trip destinations; 3) with various goods, multiple shopping centers, and multiple employment centers; and then 4) with trip chains. Finally, some suggestions for a general equilibrium model are included.

Model for Boundary Variation Using Fuzzy Approach

정명희 안양대학교 산업기술연구소 2000 自然科學硏究 Vol.7 No.-

It is difficult to identify exact boundaries and analyze variation around boundaries in scene images since each observation is the integrated response from some region of the earth's surface. The fuzzy approach allows the possibility of partial membership as a measure of the extent to which a pixel is associated with all the classes in mixed, uncertain situations. Since the regions are usually relatively large compared to the pixel size, interior regions far from boundaries are considered as pure regions with their own features which are not corrupted by other region type. A multiresolution data structure was integrated with this fuzzy approach for modeling boundary variation in order to efficiently implement the idea that interior regions have their own statistical featrues and boundary regions are affected by adjoining regions of different class types.

계수분할을 이용한 웨이블릿 패킷 영상 부호화

홍진표 안양대학교 산업기술연구소 2000 自然科學硏究 Vol.7 No.-

본 논문에서는 계수분할을 이용하여 웨이블릿 패킷 변환된 영상을 부호화하는 방법을 제안한다. 전체적인 수행시간을 줄이기 위해 엔트로피를 이용하여 영상을 웨이블릿 패킷 분할하고, 부대역간의 상관성을 이용하여 계수들을 제로트리 방식으로 부호화하여 비트율과 왜곡면에서의 성능을 보완한다. 영상 복원시오차를 감소시키기 위하여 각 주파수 부대역간의 상관성을 이용한 새로운 부모-자식노드 관계를 도출하고, 이를 이용하여 계수들에 대한 부호화 순서를 결정한다. 그 결과 새로운 웨이블릿 패킷영상 부호화기는 비트율과 제곱오차에 대해서 기존의 방법과 비교 평가하였을 때 우수한 성능을 나타내었다. A wavelet packet image coder which is based on the coefficients partition for efficiently encoding the image is proposed. The wavelet packet decomposition scheme by the first-order entropy provides a fast implementation of the encoder and the zerotree-based coding a very good rate-distortion performance. To reduce the reconstruction error, a new parent-children relationship using the correlation between the subbands is proposed and then the wavelet packet coefficients are partitioned by a new order. The result indicate that this new wavelet packet image coder produces the satisfiable performance both compression rate and quadratic error. The computer simulation is applied to evaluate performances of the designed network. The algorithm proposed in this study is a heuristic one with polynomial time complexity. This method was tested on sample problems and proved to be superior to the conventional ones.

한국 프로골프 선수들의 상금획득에 영향을 미치는 요인분석

이태섭 안양대학교 산업기술연구소 2004 自然科學硏究 Vol.11 No.1

한국프로골프협회 소속 118명 선수들의 2003년도 획득상금에 영향을 미치고 있는 요인에 대하여 회귀분석을 통하여 알아보았다. 여기서 선수들의 획득상금을 설명하기 위한 독립변수로는 평균타수, 그린적중률, 평균퍼팅수, 이글수, 버디수, 파수 및 파세이브율을 설정하여 회귀모형을 추정하였다. 그 결과 프로골프 선수들의 획득상금에는 평균타수, 파수 및 이글버디수가 유의한 영향을 미치고 있었으며, 선수들의 성적보다는 경기특성에 따라 달라질 수 있는 변수라고 생각되는 그린적중률과 평균퍼팅수는 획득상금과는 직접적인 관련이 없는 것으로 나타났다. The purpose of this study is to evaluate the earnings of professional golf players in KPGA. Data were collected from 118 players of KPGA through the website www.koreapga.com. In this study, seven independent variables - scoring average, greens in regulation percentage, putting average, total eagles, total birdies, total pars, and scrambling - are used to explain the variation of earnings for KPGA players. From this study, the followings can be concluded. 1. The determining variables are scoring average, total pars, and total eagle-birdies. 2. The variables greens in regulation percentage and putting average have no big influence on earnings of professional golf players.

전력산업 구조개편하에서의 DSM 참여방안 전력산업 구조개편하에서의 DSM 참여방안

원종률 안양대학교 산업기술연구소 2004 自然科學硏究 Vol.11 No.1

최근 전력 분야에 경쟁이 도입되면서 1980년대부터 적극 추진되었던 수요관리(DSM)도 형태를 달리 하여야 할 때이다. 이에 따라 새로운 구조개편 시장체제하에서 기존의 부하관리와 비교되어 공익적 수요관리로서 계속 남아 있는 고효율기기를 새로운 시장체제하에서 수요측입찰(Demand-Side Bidding)이라는 제도에 참여할 수 있는 방안을 제시하고 이에 대한 비용/이익 효과를 비교 분석하였다. 또한 정책적 수단으로서 시장체제하에서 고효율기기의 능동적 보급방안을 제시하였다. Recently, as competiton has been made in the electricity industry sector, traditional demand-side management(DSM), which has been promoted since 1980 in Korea, should also be adapted to the changing environment. This paper presented the active participation method of energy efficiency equipment remaning as public demand-side management, compared to traditional load management, into demand-side bidding(DSB) system in the new electricity market, and its cost/benefit analysis was proposed. Active distribution methods of energy efficiency DSM policy are also proposed.

Design of Dictionary for Korean Morphological Analysis

Lim, Kwon-Mook 안양대학교 산업기술연구소 1998 自然科學硏究 Vol.5 No.2

This paper presents a design method for the dictionary used by the Korean morphological analyzer. A morpheme dictionary and a word dictionary have been designed with lexical database. Efficiency of morphological analyzer depends on the informations in the dictionaries. Word's characteristics and adjacency informations can be obtained from sentences in a large corpus. The collected morphime's adjacency attributes and relations with neighbor words are recorded in a well designed words as welll as ambiguous words can be almost analyzed successfully.

Data Model for Incomplete Information in Temporal Databases

Byun, Siwoo 안양대학교 산업기술연구소 2000 自然科學硏究 Vol.7 No.-

The objective of this research is to reduce the uncertainty of user query for incomplete information in temporal databases. In data models for incomplete information in temporal databases, we must consider two mechanisms, estimation and uncertainty handling mechanism. Typical method to give more informative answers to users is interpolation method. And there has been few researches in the area of handling uncertainty for incomplete information without user-defined probability. But uncertainty handling mechanism with user-defined probability approaches is not desirable to let users catch the meanings of the stored data and the users are not familiar to difficult and complex probability functions. In this paper, a new approach of handling uncertainty, Reliability Logic(RL) model, is proposed, which provides users generality and naturalness of query expression for incomplete information. In Reliability Logic model, two basic reliability operators are introduced into restriction clause. The extension to Reliability Logic model can give the users expressive power of user query, notify the degree of uncertainty and reduce the uncertainty of the user query.

새로운 정지영상 압축 표준안에 관한 고찰

김호경 안양대학교 산업기술연구소 2001 自然科學硏究 Vol.8 No.-

기존에 사용되고 있는 정지영상 압축 표준안인 JPEG가 사용된 것도 어언 10년 가까이 되었다. 그 동안 인터넷의 사용을 보편화하였던 웹 브라우저의 출현은 멀티미디어 데이터의 사용을 더욱 가속화시켰으며, 점점 더 질적으로 나은 영상의 사용을 요구할 뿐만 아니라 영상의 크기 또한 훨씬 큰 영상을 데이터로 사용하고 있다. 통신 네트워크의 전송 속도의 향상을 위하여 하드웨어 면에서도 많은 발전을 이루고 있으나, 소프트웨어의 측면에서도 정지영상의 압축률을 높이려는 노력도 요구되었다. 이와 같은 노력의 일환으로 새로운 정지영상 압축의 표준안인 JPEG 2000이 제안되었다. 본 논문에서는 JPEG 2000 표준안에 대하여 살펴보고자 한다. The JPEG standard has been in use for almost ten years now. The development of web browser making the internet popular accelerates the use of multimedia. Not only is the high quality sacnned image needed but also the bigger size of image for multimedia. In order to improve the speed of computer network, there are a lot of improvement in as software well as hardware for the high image compression rate. As an effort for these, the new standard of still image compression such as JPEG 2000 is prepared. In this paper we will discuss the still image compression standard of JPEG 2000.