• Bulletin of the Korean Chemical Society
• /
• 제30권10호
• /
• pp.2287-2293
• /
• 2009

Gas Chromatography-Mass Spectrometry (GC-MS) fingerprint analysis, Principle Components Analysis (PCA), and Hierarchical Cluster Analysis (HCA) were introduced for quality assessment of Curcuma longa L. (C. longa). The GC-MS fingerprint method was developed and validated by analyzing 33 batches of samples of C. longa from different geographic locations. 18 chromatographic peaks were selected as characteristic peaks and their relative peak areas (RPA) were calculated for quantitative expression. Two principal components (PCs) were extracted by PCA. C. longa collected from Guizhou and Fujian were separated from other samples by PC1, capturing 71.83% of variance. While, PC2 contributed for their further separation, capturing 11.13% of variance. HCA confirmed the result of PCA analysis. Therefore, GC-MS fingerprint study with chemometric techniques provides a very flexible and reliable method for quality assessment of C. longa.

• 대한임베디드공학회논문지
• /
• 제7권5호
• /
• pp.267-275
• /
• 2012

In this paper, we present the model-based autonomic computing framework for a cyber-physical system which provides a self-management and a self-adaptation characteristics. A development process using this framework consists of two phases: a design phase in which a developer models faults, normal status constrains, and goals of the CPS, and an operational phase in which an autonomic computing engine operates monitor-analysis-plan-execute(MAPE) cycle for managed resources of the CPS. We design a hierachical architecture for autonomic computing engines and adopt the Model Reference Adaptive Control(MRAC) as a basic feedback loop model to separate goals and resource management. According to the GroundVehicle example, we demonstrate the effectiveness of the framework.

• 한국통신학회논문지
• /
• 제25권1A호
• /
• pp.18-26
• /
• 2000

Yeung은 중첩구조 셀룰라 시스템에서 사용자의 mobility model에 적합한 효과적인 채널관리 방안을 제시하였다. 이 방안은 기존의 중첩구조 셀룰라 시스템의 채널할당방식을 개선하여 사용자의 mobility를 추가로 고려하였으며 사용자를 저속사용자와 고속 사용자로 구분하여 각각 마이크로, 마크로셀에 호를 할당하는 방법이다. 본 논문에서는 Yeung의 시스템을 개선한 방식을 제안하여 Yeung의 시스템과 기존 시스템과의 성능을 비교해 보았다. 블록킹 확률을 비교하기 위해 큐일모델 분석을 하였고, 시뮬레이션을 통해 성능을 검증하였다. 그 결과 본 논문에서 제시한 방법이 좀 더 나은 성능을 보임을 알 수 있었다.

• 한국지능시스템학회논문지
• /
• 제10권4호
• /
• pp.285-292
• /
• 2000

자료 분석 과정을 살펴 보면 1) 자료가 갖는 경향 평가, 2) 클러스터 분석, 3) 클러스터의 타당성 조사라는 과정을 거쳐 이루어진다. 이 분석법은 2) 및 3) 단계의 반복 수행으로 인하여 많은 계산 시간이 소요되므로 비효율적인 방법이라 할 수 있다. 본 논문에서는, 이와 같은 단점을 보완하기 위하여 자료가 갖는 개략적 특성을 파악하여 자료 속에 존재하는 클러스터의 근사적 개수 및 중심을 정한 후, 이 정보를 기존의 일반적인 퍼지 클러스터링 알고리즘에 입력하여 클러스터링을 수행하는 밀도함수를 이용한 계층적 구조의 근사적 클러스터링 알고리즘을 제안하고, 예제를 통하여 제안된 알고리즘의 타당성을 보인다.

• 전기학회논문지
• /
• 제59권11호
• /
• pp.1971-1979
• /
• 2010

As a result of increasing environmental concern, the penetration of renewable power on power systems is now increasing. Wind energy can be considered as the most economical energy sources to generate electricity without depletion of fossil fuel. To devise adequate control strategies for wind farm, time domain simulation analysis needs to be performed. This presents a continuation time integration (CTI)-based time domain simulation algorithm for wind farm with doubly fed asynchronous generator (DFAG) connected to the external power systems. This paper depicts how to time trajectories are traced using CTI-based time domain simulation. Also this paper describes the possibilities of hierachical control for wind farm output limitation, and the coordinated control has been designed by hierarchical control structured from central control level to wind farm control board and to an individual wind turbine level. Finally it shows an illustrative example of time domain simulation result with two test systems through case study.

• 한국사회복지학
• /
• 제58권3호
• /
• pp.371-398
• /
• 2006

본 연구는 돌봄경험의 긍정적 측면을 조명하기 위한 목적으로 지역사회에서 정신장애인을 돌보는 어머니를 대상으로 돌봄만족감의 수준이 어느 정도이며, 어떤 요인들이 이에 영향을 미치는지에 관해 알아보았다. 연구대상자는 서울 및 경인지역의 지역정신보건센터, 사회복귀시설 및 낮병원을 이용하는 정신장애인을 돌보는 어머니이며, 총 231명이다. 돌봄만족감에 영향을 미치는 요인에는 정신장애 관련 요인으로 정신장애인의 유병기간, 입원횟수 및 사회기능이, 어머니의 개인적 요인으로 연령, 결혼상태, 가족수입, 신체적 건강이, 그리고 관계적 요인으로 정신장애인과 어머니관계의 질과 어머니가 가족, 친구 및 의미 있는 타자와의 관계를 통해 받는 사회적 지지가 포함되었다. 자료분석을 위해 t-test, Oneway-ANOVA, 상관관계분석, 그리고 위계적 다중회귀분석(hierachical multiple regression analysis) 등이 사용되었다. 연구결과 어머니의 돌봄만족감은 5점 척도에서 평균 3.06점으로 중간보다 약간 높게 나타났다. 최종 회귀분석모델에서 어머니의 돌봄만족감에 유의미한 영향을 미치는 요인은 어머니의 결혼상태, 가족수입, 정신장애인과의 관계의 질, 그리고 사회적 지지였으며, 정신장애인의 사회기능 등 정신장애 관련 요인은 돌봄만족감에 유의미한 영향을 미치지 않았다. 본 연구의 결과를 통해 돌봄경험의 긍정적 측면으로 실재하는 돌봄만족감에 대한 실천적 관심이 필요함과 더불어 이를 증진하기 위한 사회복지실천적 개입 방안이 연구의 함의로 제시되었다.

• 한국의류학회지
• /
• 제24권5호
• /
• pp.652-662
• /
• 2000

Most of established study about consumer behavior was directly connected abstract value with concrete purchase behavior, nevertheless several recognizable process is intervened between abstract concept and concept behavior. Of course researchers suggest hierarchical causality through means-end chain model. However empirical study is insufficient. And it's not certain whether the consumer's personal value affects actual evaluation about product attributes. Thus the purpose of this paper was to explore hierarchical causality of personal value, benefits sought and clothing product attributes and to suggest an alternative approach method. For the empircial study the data sets were collected through 150 female consumers living in Pusan and SAS and LISREL VIII were used for statistical analysis. As the result, hierarchical causality suggested by means-end chain model was positively substantiated. That is, benefits sought is differentiated according to personal value, and actual product attributes are indirectly influenced by personal value through benefits sought. Benefits sought are found to be key mediating variables.

• 한국보육지원학회지
• /
• 제14권4호
• /
• pp.109-126
• /
• 2018

Objective: The purpose of the present study was to explore the moderating role of children's verbal ability in the relation between shyness and teacher-child relationships. Methods: Participants were 200 children, their mothers, and their kindergarten teachers. Children's shyness was rated by their mothers and teachers, and children's verbal ability was measured using the language problem solving ability test. And teachers completed a rating scale in order to examine the teacher-child relationship. The collected data were analyzed using correlations and hierarchical multiple regressions. Results: Children's shyness had a negative relation to close teacher-child relationships. And child's verbal ability was significantly related to teacher-child relationships. Hierachical regression analysis indicted to the interaction of child's shyness and verbal ability predicted close teacher-child relationships. Children's shyness, those who demonstrated the lowest level of child's verbal ability, was significantly associated with close teacher-child relationships. Children's shyness had no significant relation to close teacher-child relationships, especially for the highest level of children's verbal ability. Conclusion/Implications: We suggested that verbal ability training for children might be valuable for shy children in order to buffer the link between shyness and teacher-child relationships.

• 임상간호연구
• /
• 제24권3호
• /
• pp.313-323
• /
• 2018

Purpose: This cross-sectional survey study explored the moderating effect of social support between hierarchy-oriented nursing organizational culture and turnover intention in clinical nurses. Methods: Data were collected using self-report questionnaires from 240 nurses working at three general hospitals in February 2018. Hierarchy-oriented nursing organizational culture, turnover intention and social support were measured using 5, 6, and 8 items, respectively, of validated instruments. Descriptive analysis and hierachical multiple regression were conducted using SPSS/WIN 21.0. Results: Nurses rated $3.66{\pm}0.50$ for hierarchy-oriented nursing organizational culture, $3.40{\pm}0.64$ for turnover intention, and $3.77{\pm}0.56$ for social support respectively. Nurses' turnover intention was positively correlated with hierarchical organizational culture, but negatively with social support. The moderating effect of social support was not significant in the relationship between hierarchical nursing organizational culture and turnover intention. Conclusion: It is required to improve the hierarchy-oriented nursing organizational culture. Institutional preparation and education are urgently needed to strengthen the boss and peer support for clinical nurses and finally to reduce turnover intention.

• 한국정밀공학회지
• /
• 제14권11호
• /
• pp.135-146
• /
• 1997

This paper describes fault diagnosis method in complex system with hierachical structure similar to human body structure. Complex system is divided into unit, item and component. For diagnosing this hierarchical complex system, it is necessary to implement special neural network. Fault diagnosis system can forecast faults in a system and decide from current machine state signal information. Comparing with other diagnosis system for single fault, the developed system deals with multiple fault diagnosis comprising Hierarchical Neural Network(HNN). HNN consists of four level neural network, first level for item fault symptom classification, second level for item fault diagnosis, third level for component symptom classification, forth level for component fault diagnosis. UNIX IPC(Inter Process Communication) is used for implementing HNN wiht multitasking and message transfer between processes in SUN workstation with X-Windows(Motif). We tested HNN at four units, seven items per unit, seven components per item in a complex system. Each one neural newtork operate as a separate process in HNN. The message queue take charge of information exdhange and cooperation between each neural network.