• Smart Structures and Systems
• /
• 제16권6호
• /
• pp.1107-1132
• /
• 2015

A damage detection algorithm based on neuro fuzzy hybrid system is presented in this study for location and severity predictions of cracks in beam-like structures. A combination of eigenfrequencies and rotation deviation curves are utilized as input to the soft computing technique. Both single and multiple damage cases are considered. Theoretical expressions leading to modal properties of damaged beam elements are provided. The beam formulation is based on Euler-Bernoulli theory. The cracked section of beam is simulated employing discrete spring model whose compliance is computed from stress intensity factors of fracture mechanics. A hybrid neuro fuzzy technique is utilized to solve the inverse problem of crack identification. Two different neuro fuzzy systems including grid partitioning (GP) and subtractive clustering (SC) are investigated for the highlighted problem. Several error metrics are utilized for evaluating the accuracy of the hybrid algorithms. The study is the first in terms of 1) using the two models of neuro fuzzy systems in crack detection and 2) considering multiple damages in beam elements employing the fused neuro fuzzy procedures. At the end of the study, the developed hybrid models are tested by utilizing the noise-contaminated data. Considering the robustness of the models, they can be employed as damage identification algorithms in health monitoring of beam-like structures.

• 보건의료산업학회지
• /
• 제7권3호
• /
• pp.203-212
• /
• 2013

Medical devices separated by a committee of the International Electrotechnical Commission IEC TC (Technical Committee) 62 medical electrical equipment being promoted by the International standards. Actually, a lot of standards were existed, but many national and international standards for medical devices were lacking in practical standards that can be applied to their development. Most international standards were focused in electrical and mechanical safety of medical devices. Therefore, there were few practical standards which contain essential performance evaluation. Although medical device regulations do not enforce a fixed lifecycle model, activities are presented in a sequential manner, thus hinting at a waterfall process. Meanwhile, for a decade or more, software teams have benefitted from agile development methods. Several medical device manufacturers have adopted agile practices while keeping development in compliance with regulations, but conflicts arise and decisions have to be taken in favor of agility or formality. However, if there are new practical standards of medical devices, it must be possible to promote the medical devices industry in their nation. To do this, there is a need to develop a new standard could apply to the international market through the analysis of the medical device related technology. Consequently, new standards such as NP (New proposal) or NWIP (New Work Item Proposal) should be developed through international standardization of medical device technology.

• The Journal of Asian Finance, Economics and Business
• /
• 제7권3호
• /
• pp.53-62
• /
• 2020

The study aims to provide some plausible explanation for why Vietnamese listed companies only stop at the level of truthful presentation of information related to accounting data through the opinion of independent auditors. The information is only at the level of compliance with the requirements of Circular 155/2015/TT-BTC in form, but in essence is sketchy. What factors affect the level of voluntary disclosure of listed companies in Vietnam? In order to identify the factors affecting voluntary information disclosure on annual reports of listed companies, the study collected data on annual reports of 122 companies listed on the stock market in Ho Chi Minh City in the period 2015-2018 and uses regression analysis methods. The research presents 8 factors affecting the level of voluntary information disclosure including: Firm size, Listed time, Profitability, Solvency, Separation of board of directors and executive director, Board size, Organizational ownership and Foreign ownership. Next, the study conducted descriptive statistical analysis correlation coefficient analysis to examine the correlation and relevance of independent variables measured by the scale ratio, testing multiple linear regression model. The results of the study show that factors listed time, profitability and organizational ownership affecting voluntary information disclosure on annual reports of listed companies in Vietnam.

• 한국멀티미디어학회논문지
• /
• 제7권3호
• /
• pp.293-307
• /
• 2004

XML 기반의 SMIL(Synchronized Multimedia Integration Language) 문서는 문서를 구조적인 특성에 따라 논리적 구조 정보, 공간적 구조 정보, 시간적 구조 정보, 하이퍼링크 구조 정보로 표현할 수 있다. 본 논문은 이와 같이 SMIL 문서에 내재된 다중 구조 정보를 효과적으로 모델링하고, 관련 정보를 검색할 수 있는 기능을 지원한다. 특히, 본 논문에서는 SMIL문서의 구조 정보에 대한 객체 클래스와 클래스간의 계층 구조 및 관계를 표현하기 위해 UML의 클래스 다이어그램을 이용하여 객체 지향 모델링을 제공한다. 또한 객체 클래스들을 정의하기 위해 데이터베이스 표준 언어인 SQL3를 이용하고 있다 그밖에, SMIL 문서의 구조적인 구성 요소들을 효과적으로 검색하기 위해 계층 구조 접근 연산을 제공하며, SMIL문서의 효율적인 검색을 지원하고 있다.

• 한국안전학회지
• /
• 제25권4호
• /
• pp.76-83
• /
• 2010

As one of crucial industries, the service industry occupies a large part of economy in Korea poor in natural resources. However, prevention of industrial disasters has been promoted mainly in manufacturing and construction industries where the frequencies of such disasters and victims are high. Research on the evaluation of workplace safety climate has been conducted centering on traditional industries like manufacturing and construction, and few studies have been made for service businesses. The objective of this study was to evaluate workplace safety climate perceived in the field by workers engaged in service businesses and to contribute to the establishment of industrial safety and health policies in consideration of the characteristics of each business category. Using research variables safety knowledge, safety attitude, safety motivation, safety participation, safety compliance, and safeness of work environment, we evaluated comprehensive workplace safety climate based on the causal relations among the variables. In the results of analyzing data from a questionnaire survey of service business employees, statistically significant effect relations among the variables were identified, and the fitness of the model with approved reliability and validity was verified.

• 한국항공우주학회지
• /
• 제42권11호
• /
• pp.911-918
• /
• 2014

본 논문에서는 응집영역 모델링 방법에 의한 균열전파 해석에서 발생하는 연성추가문제의 효과적인 해결방법으로 사용자 부프로그램 UMPC를 이용한 응집요소의 선택적 활성화 기법을 연구 하였다. 먼저 균열의 발생 및 전파가 예상되는 지역의 일반요소들 사이에 응집요소를 삽입하고 응집요소를 구성하는 절점에 다중점 구속조건을 적용함으로써 응집 요소를 비활성화 시킨 상태로 해석을 시작한 후, 해석 도중에 특정 조건을 만족하는 절점들에 대해서만 다중점 구속조건을 해제하여 응집요소를 선택적으로 활성화하는 전략을 사용하였다. 응집요소의 초기강성 및 다중점 구속조건 해제 지표가 균열전파 거동 및 계산시간에 미치는 영향을 체계적으로 조사하였다.

• 한국해양공학회지
• /
• 제24권1호
• /
• pp.153-160
• /
• 2010

This paper deals with the topology optimized design of the riser support structures for floating production storage and offloading units (FPSOs) under global and local loading conditions. For a preliminary study and validation of the numerical approach, a simplified plate under static loading is first evaluated with the representative topology optimization methods, the Homogenization Design Method (HDM) and Density Method (DM) or Simple Isotropic Material with Penalization (SIMP). In the context of the corresponding riser support structures, the design problem is formulated such that structure shapes based on design domain variables are determined by minimizing the compliance subject to a mass target, considering the stress criterion. An initial design model is generated based on an actual FPSO riser support configuration. The topology optimization results present improved design performances under various loading conditions, while staying within the allowable limit of the offshore area.

• 한국지능시스템학회논문지
• /
• 제23권1호
• /
• pp.12-17
• /
• 2013

본 논문에서는 컴플라이언스 특성의 발을 갖는 이족 로봇의 다리 메커니즘을 제시한 후, 이족 로봇을 위한 전형적인 보행 패턴에서 발의 접촉 반발력과 이것이 무릎과 힙 관절에 미치는 영향을 고찰하고자 한다. 이러한 분석은 보행 로봇이 걸음 동작을 수행할때, 발의 물리적인 접촉력의 영향을 파악하는데 있어서 유용하고, 다리 메커니즘의 관절 사양을 결정하는데 활용될 수 있다. 결과적으로, 로봇 발 메커니즘의 컴플라이언스 특성이 발의 접촉 반발력에 의해 영향을 받는 보행 다리 관절의토오크 특성을 완화시키는데 기여할 수 있음을 보인다.

• 지역사회간호학회지
• /
• 제17권2호
• /
• pp.283-294
• /
• 2006

Purpose: The purpose of this study was to identify the factors influencing childhood immunization. Method: Data were collected by questionnaires from 251 Parents who have 6 months to 7 years old children at public health centers in Seoul and Kyunggi Province. The data were analyzed using descriptive statistics, t-test, ANOVA, and multiple regression. Result: According to general characteristics of the parents and children, there were statistically significant differences in education level of parents, child immunization card, gender, age, and birth order of children. The main factors that affected children's immunization were perceived barriers of action, perceived control, birth order of children, child immunization card, and education level of parents, and these factors explained 49.4%(explanatory power of this model was 49.4%). Conclusion: The results of this study showed strategies for compliance of children immunization. Therefore, when the program are developed for public immunization, these factors need to be considered.

• 아동학회지
• /
• 제35권4호
• /
• pp.79-101
• /
• 2014

The purpose of this study was validate the Preschool and Kindergarten Behavior Scale-2(PKBS-2) and develop the Korean version PKBS-2(K-PKBS-2) through the phases of concept and statistical review. For this purpose, this study conducted PKBS-2 for teachers with 1,119 young children in Jeonbuk province. During the factor structure review, according to the results of exploratory factor analysis, 30 items and 4 factors(social interaction, social cooperation, social compliance, and social independence) in social skills scale and 40 items and 4 sub-factors of 3 factors(internalizing behavior, externalizing behavior, and interpersonal emotional behavior) in problem behavior scale were extracted. In addition, confirmatory factor analysis, the model fits of social skills and problem behavior scales were higher than the original test and very high reliability and internal consistency were produced. During external factor review, convergent validity and discriminant validity were verified. After cultural specificity and cultural universality between PKBS-2 and K-PKBS-2 were discussed, K-PKBS-2 was presented as e scale which is very useful for the screening, prevention, and intervention program plan of challenging behavior behaviors in young children in Korea.