• 한국통신학회논문지
• /
• 제40권6호
• /
• pp.997-1004
• /
• 2015

이 논문에서는 MISO 하향 능동 안테나 시스템에서 수직 분할 기법을 연구하였다. 능동 안테나 시스템에서는 각 섹터에서 안테나 빔 패턴을 조절 가능 할 뿐만 아니라 복수의 수직 안테나 빔을 통해 수직 섹터분할도 가능하다. 수직 섹터 분할을 위한 최적 빔 기울기를 구하기 위해 기존의 전역 탐색 기법은 매우 높은 계산 복잡도를 요구하기 때문에 이 논문에서는 이러한 계산 복잡도를 낮추기 위해 두 가지 알고리즘을 제안하였다. 먼저 불규칙 행렬이론에서의 광범위 시스템 근사치를 이용하여 근사 전송률 합에 기반을 둔 알고리즘을 제안하였다. 또한, 기존의 하나의 섹터 전송 기법에서의 결과를 이용한 폐쇄 형태 표현을 가진 알고리즘도 제안하였다. 실험결과를 통해 제안된 알고리즘들이 기존의 전역 탐색 알고리즘에 비해 복잡도를 매우 감소시킴에도 불구하고 거의 비슷한 성능을 가짐을 확인하였다.

• 한방비만학회지
• /
• 제7권1호
• /
• pp.39-54
• /
• 2007

Objectives : This study has been done to know which herbs and herbal formulae are frequently used for the treatment of obesity in Korea and overseas since 2000. Methods : We conducted a computerized literature search in KISS (Korean studies Information Service System), Pubmed, Journal of Oriental Association for Study of Obesity ,and Journal of Oriental Rehabilitation Medicine(2000 -Apr. 2006) using search key words obesity, obese, weight loss, weight control combined with herb, herbal formula. Result and conclusion : Seventy-two studies have been identified(50 Korean papers and 22 pubmed papers) and 81 herbs have been found. In USA it was mainly used as single herb for food, but in Korea it was mainly used as herbal formula. For single herb, ephedra(麻黃) was the most studied single herb both in Korea and the USA. For herbal formulae, Sasang Constitutional Medicine(SCM, 19times) was the most frequently used herbal formula, in which the herbs for Tae-eum type person like Taeyeumjowui-tang(太陰調胃湯, 7times) and Choweseungcheng-tang(調胃升淸湯, 5times) were mainly prescribed. The next was Chegameuiin-tang(體減薏苡仁湯, 11times) and Bangpungtongsungsan( 防風通聖散, 3times). Calculating each herb consisted in each herbal formula, Coicis Semen(薏苡仁), Angelicae gigantis Radix(當歸), and Glycyrrhizae Radix(甘草), Raspberry Ketone, Cnidii Rhizoma(川芎), and Ephedra Herba(麻黃) turned out to be the most frequently used herb.

• 조명전기설비학회논문지
• /
• 제13권1호
• /
• pp.9-14
• /
• 1999

삼파장 형광등의 제작에서 문제가 되는 것은 원하는 목표 색을 맞추기 위하여 혼합하는 세 가지 형광물질의 혼합비율이다. 한 형광체의 광 스펙트럼이 약간 변형되거나, 공정변수에 의하여 변경되거나, Ar과 Kr 같은 불활성가스의 스펙트럼이 혼재하거나 또는 재래 할로인산칼슘이 공존할 경우 원하는 정확한 색을 찾기가 매우 힘들어지게 된다. 이 연구에서는 원하는 목표 색을 빠르게 찾는 방법을 연구하였다. 세 개의 각각의 단일색의 형광등과 3색을 서로 다른 비율로 혼합한 형광등을 만들고 각각의 스펙트럼을 측정한 후 이로부터 알곤과 수은의 스펙트럼을 빼서 변형 색 좌표를 얻었다. 이 변형 색 좌표로부터 적생에 대한 청색과 녹색의 광속비를 그의 무게 비에 대하여 도시하여 무게 대 광속비의 관계를 구하였다. 이 관계식을 이용하여 생산라인에서 삼파장 형광체의 단일 도포 및 할로인산칼슘을 1차로 도포하는 2중 도포를 실시하여 목표색을 조합해본 결과 만족할만한 결과를 얻었다.

• 한국도서관정보학회지
• /
• 제30권2호
• /
• pp.123-153
• /
• 1999

본 연구는 기존의 CD-ROM 데이터베이스 탐색형태에 관한 연구를 기초로 의학도서관에서 사용하고 있는 온라인 MEDLINE을 검색하는데 있어 연구자들이 정보이용을 보다 효율적으로 제공할 수 있는 방안을 모색하는데 그 목적이 있다. 의학도서관에서의 MEDLINE 탐색형태를 조사하기 위하여 정보이용 행태에 관한 문헌조사와 실태조사를 설문지 조사방법으로 60개 의학도서관을 대상으로 의학전문사서의 정보이용 행태를 추출하였다.

• 한국가족복지학
• /
• 제55호
• /
• pp.189-236
• /
• 2017

본 연구는 지역사회 거주 청소년 한부모의 자녀양육 경험을 심층적으로 탐색하기 위해 Giorgi 의 현상학적 연구 방법을 적용하였다. 연구참여자들은 16~24세에 자녀를 출산하고 현재 6개월~11세 자녀를 둔 지역사회 거주 재가 청소년 한부모 8명이다. 연구 결과, 140개의 의미단위, 34개의 하위구성요소, 7개의 구성요소가 도출되었다. 최종 구성요소는 '충족되지 못한 현재로부터 벗어나기 위해 시작됨', '뜻하지 않게 닥친 선택의 기로에서 갈등함', '청소년 한부모삶으로의 진입과 적응의 힘겨움', '재가 청소년 한부모의 자녀 양육과정에서 마주한 차가운 현실의 벽', '어린 부모로 최선의 부모됨을 위한 역할 찾아가기', '한부모로서 나를 찾아가는 과정에서의 변화와 성장', '더 나은 청소년 한부모 삶을 위한 염려와 바람'으로 분석하였다. 연구결과를 바탕으로 지역사회 거주 청소년 한부모의 자녀양육 경험과 의미를 이해하고, 그들에대한 제도적 지원과 사회 시선의 변화가 모색되길 바라면서 논의 및 제언을 하였다.

• 영어어문교육
• /
• 제13권3호
• /
• pp.99-116
• /
• 2007

Indeterminacy, along with the traces of the unknown identity V, plays a crucial role in building a new possibility in the narrative V. While the characters search for the single identity of V, Pynchon never lets readers and critics reach any final destination or goal in analyzing the novel. Exploring the multiple possibilities and meanings of life, the characters merely keep traveling and searching, without ever reaching any final conclusion or destination. The journey without ever reaching a final destination equals going beyond the boundary and embracing the margins of various possibilities. It concerns the Others and breaks off the hierarchy of Western metaphysics, which is quite similar to what the theorists of deconstruction seek to do. The search without ever reaching a final destination not only designates the multifarious aspect of truth, but it also suggests the possibility of the multiple meanings of words that the characters create. Just as their stories are abundant, the meaning that they produce with their stories can be open-ended. The notion of indeterminacy and broadness in this text, which can be well explained by Derrida, makes it possible for one to search for something other than the fixed meanings or truth claims. The text becomes multifarious in meaning as well as in structure, thus rejecting any kind of singular signifying act.

• Journal of Advanced Marine Engineering and Technology
• /
• 제32권8호
• /
• pp.1269-1277
• /
• 2008

Ships at sea cannot exchange data among them easily so far. Basically voice-oriented communication systems are the main methods, some of them utilize the HF radio systems at lower bit rates, and for higher bit rates, the Inmarsat or VSAT are adopted. None of them are used widely because of lower qualities and higher costs. There exist many technical and economical limits to have the Internet service just like on land such as the WWW service. In order to achieve the improved transmission rates of the maritime communication networks at farther sea, MANET(Mobile Ad Hoc Network) is one of the most practical models. In this paper, a new routing protocol named EZR (Expansive Search Zone Routing Protocol) is proposed, which is based on SANET (Ship Ad Hoc Network) model that has some different features from MANET and VANET (Vehicular Ad Hoc Network). The search zone for the shortest path is firstly found by EZR. If no path is searched in the zone, the zone is expanded according to the rule of EZR. The zone-expanding and path-searching procedures are repeated until the path is found out. The performance of EZR is evaluated and compared with LAR protocol which is one of the most typical routing protocols based on geographical information. The simulated results show that EZR is much better than LAR at sea environments in terms of routing success rate, route optimality, and a single index of performance combined the previous two metrics.

• 한국도서관정보학회지
• /
• 제15권
• /
• pp.207-243
• /
• 1988

This study is an attempt to furnish some helpful data for the maximum use of online information retrieval systems based on the comparative analysis of commands and operating terms employed by DIALOG, ORBIT and BRS which are three largest information retrieval systems in the world. To begin with, the historical development, service contents and retrieval functions of three systems were overviewed in the second chapter, on the basis of which the concrete functions and contents of the commands and the operating terms of the three systems were compared and analyzed one another. Commands were explained divided into basic and special ones. The basic commands subdivided into 44 items were put into the form of a diagram(Table 1). The special commands were first subdivided into search commnad, output-related commands and su n.0, pplementary commands, and then 14 items of which were comparatively analyzed and were represented as a chart(Table 2). In addition, any stand-alone commands employed by each system were also analyzed as a chart(Table 3). The Operating terms other than commands were subdivided into 16 items and were represented as a chart(Table 4). Password, inverted file, search step number in search session, etc were explained to the very detailed extent. A self-evident, single word is that the through understanding of commands is essential to the maximm use of all the functions of each of three systems.

• 한국비블리아학회지
• /
• 제7권1호
• /
• pp.231-246
• /
• 1994

A major problem for information retrieval research in the past three decades has been methodology, even though some progress has been made in obtaining useful results from methodologically sound experiments. Within a methodology, potential problems include artificial data generated by the researcher, small sample size interpretation of findings. Critics have pointed out that some room exists for improving methodology of information retrieval research; using existing data, having big enough sample size, including large numbers of search queries, introducing more control in relation to variables, utilizing more appropriate performance measures, conducting rests carefully and evaluating findings properly. Relevance judgments depend entirely on the perception of the user and on the situation of the moment. In an experiment, the best judge of relevance is a user with a well defined information need. Normally more than two categories for relevance judgments are desirable becase there are degrees of relevance. In experimental design, careful control of variables is meeded for internal validity. When no single database exists for comparison, existing operational databases should be used cautiously, Careful control for the variations of search queries, inter-searcher sonsistency, intra-searcher consistency and search strategies is necessary. Parametric statistics requiring rigid assumptions are not appropriate in information retrieval research and non-parametric statistics requiring few assumptions are necessary. Particularly, the sign test and the Wilcoxon test are good alternatives.

• 한국도로학회논문집
• /
• 제16권6호
• /
• pp.115-120
• /
• 2014

PURPOSES : This research describes how to predict the life cycles of fatigue cracking based on NCHRP Report 704 as well as modified harmony search (MHS) algorithm. METHODS : The fatigue cracking regression model of NCHRP Report 704 was used in order to calculate the ESAL (Equivalent Single Axle Load) numbers up to pavement failure, based on using material parameters, composite modulus, and surface pavement thickness. Furthermore, the MHS algorithm was implemented to find appropriate material parameters and other structural conditions given the number of ESALs, which is related to pavement service life. RESULTS : The case studies show that the material and structural parameters can be obtained, resulting in satisfying the failure endurance of asphalt concrete structure, given the number of ESALs. For example, the required ESALs such as one or two millions are targeted to satisfy the service performance of asphalt concrete pavements in this study. CONCLUSIONS : According to the case studies, It can be concluded that the MHS algorithm provides a good tool of optimization problems in terms of minimizing the difference between the required service cycles, which is a given value, and the calculated service cycles, which is obtained from the fatigue cracking regression model.