• 한국생산제조학회지
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• 제8권2호
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• pp.126-136
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• 1999

We studied on crack growth retardation in single overloading condition. Crack tip branching which as the second mechanism on crack growth retardation was examined. Crack tip branching was observed to kinked type and forked type. It was found that the branching angle range was from 25 to 53 degree. The variations of crack driving force with branching angle were calculated with finite element method The variation of {{{{ KAPPA _I}}}}, {{{{ KAPPA _II}}}} and total crack driving force(K) were examined respectively So {{{{ KAPPA _I}}}}, {{{{ KAPPA _II}}}} and K mean to mode I, II and total crack driving force. Present model(Willenborg's model) for crack growth retardation prediction was modified to take into consideration the effects of crack tip branching When we predicted retardation with modified model. it was confirmed that predicted and experimental results coincided with well each other.

• 한국컴퓨터정보학회논문지
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• 제7권4호
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• pp.40-45
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• 2002

급변하는 IT 환경에서 시스템의 재사용성을 높여 라이프타임을 증가시키고 비용을 절감하기 위한 다양한 노력들이 이루어져 왔다. 구조적 프로그래밍 기법에서는 모듈에 기반한 아키텍처를 활용하여 생산성을 향상시켰다. 그러나 모듈들은 단순히 호출 빈도를 높일 뿐, 성장이나 진화를 하지 못하는 한계 상황에 직면하게되었다. 객체지향 기법은 클래스들을 상속시키거나 메소드를 재정의 함으로써 시스템의 성장과 진화를 가능케 하여 구조적 프로그래밍 기법의 한계를 극복하였다. 최근 CORBA. COM+와 EJB/J2EE 같은 분산 처리 기술과 객체 지향 기법이 융화되어 생성된 컴포넌트 아키텍처는 고도의 재사용성이나 라이프타임의 증가뿐만 아니라 플러그-앤-플레이(Plug-&-Play)도 지원한다. 그러나 이제 컴포넌트를 구축하는데 국한된 문제가 발생하는 것이 아니라 컴포넌트 플랫폼간 연동의 문제가 제기되고 있다. 본 연구에서는 이러한 문제를 해결하기 위해 이형의 컴포넌트 플랫폼간 상호 운영성 보장 방안을 제안한다.

• 한국직업건강간호학회지
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• 제16권1호
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• pp.89-97
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• 2007

Purpose: The purposes of this study were to identify the scores of perceived job stress, health perception and health promoting life style in community health nurses and to define the correlations of three variables. Method: The data were collected by 68 subjects, using the self-reported questionnaires. The data were analyzed using descriptive statistics, t-test, one-way ANOVA, and pearson correlation coefficient. Result: The mean score of job stress was $3.19({\pm}.60)$, health perception scale was $3.04({\pm}.49)$ and health promoting life style profile was $2.49({\pm}.30)$. The relationship among job stress, health perception and health promoting life style were not statistically significant. The relationships between age, overloading job, knowledge & skill deficit and problem of interpersonal relationship were statistically significant. The relationship between religion and problem of interpersonal relationship was statistically significant. The relationships between single of marital status, knowledge & skill deficit and problem of interpersonal relationship were statistically significant. The relationship between career and stress management was statistically significant. Conclusion: These results suggested that health promotion program for community health nurses to reduce job stress, promoting health promoting life style should be carefully developed so as to provide better quality of health care services to the community people.

• 한국전산유체공학회지
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• 제18권3호
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• pp.51-59
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• 2013

A significant change in aerodynamic characteristics of wind turbine blade can occur by ice formed on the surface of the blade operated in cold climate. The ice accretion can result in performance loss, overloading due to delayed stall, and excessive vibration associated with mass imbalance. In this study, the impact of ice accretion on the aerodynamic characteristics of NREL 5MW wind turbine blade sections is examined by a CFD-based method. It is shown that the thickness of ice accretion increases from the root to the tip and the effects of icing conditions such as relative wind velocity play a significant role in the shape of ice accretion. In addition, the computational results are used to assess the degradation in the lift and drag coefficients of the blade sections.

• The Journal of the Acoustical Society of Korea
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• 제17권4E호
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• pp.28-34
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• 1998

In most switching system, the processing unit is designed to work efficiently even at relatively high loads, but when the offered traffic exceeds a particular level, the rate of completed calls can fall drastically. A single call handled by the switching system consists of a sequence of events or messages that has to be processed by the control unit. The control unit is not only incapable of handling all of the offered calls, but also its call handling capability can drop as the offered load increases. The real time available for call processing is a critical resource that requires careful management. Therefore, the overloading of this resource must be detected by a subscriber in the from of a dial tone delay or an uncompleted call which is either blocked or mishandled. The subscriber may respond by either dialing prematurely or by re-attempting a call. This action can further escalate the processors load, which is spent for uncompleted calls. Unless a proper control is used, the switching system can finally break down. In this paper, we paper, we propose a fuzzy overload detection and control method for switching systems, which can by generating fuzzy rules via fuzzy aggregation networks. Simulation results involving a switching system is given.

• 한국정보통신학회논문지
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• 제11권4호
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• pp.745-753
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• 2007

웹 서비스는 분산 컴퓨팅의 차세대 주자로 인터넷 상에서 표준 기술을 통해서 이용될 수 있는 모든 비즈니스 처리를 의미하는 분산 솔루션이다. 웹 서비스는 웹 인터페이스를 통해서 기능을 수행한다. 본 논문에서는 이러한 웹 서비스 절차를 단축시켰다. WSDL을 저장하기 위한 데이터 베이스로 WSDL Repository를 이용하였다. 서비스 제공자가 서비스를 등록할 때 서비스에 대한 정보를 UDDI Registry에 저장하게 하고, 이 때 WSDL을 같이 전송하도록 구현했다. WSDL Repository는 WSDL 뿐만 아니라 웹 서비스에 대한 서비스 정보를 갖고 있는 UDDI도 저장한다. UDDI Registry에 저장된 서비스에 대한 정보와 WSDL의 연결은 UDDI에서 데이터 필드로 구성했다.

• 한국컴퓨터정보학회논문지
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• 제6권3호
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• pp.23-28
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• 2001

급변하는 IT환경에서 시스템의 재사용성을 높여 라이프타임을 증가시키고 비용을 절감하기 위한 다양한 노력들이 이루어져 왔다. 구조적 프로그래밍 기법에서는 모듈에 기반한 아키텍처를 활용하여 생산성을 향상시켰다. 그러나 모듈들은 단순히 호출 빈도를 높일 뿐, 성장이나 진화를 하지 못하는 한계 상황에 직면하게 되었다. 객체지향 기법은 클래스들을 상속시키거나 메소드를 재정의 함으로써 시스템의 성장과 진화를 가능케 하여 구조적 프로그래밍 기법의 한계를 극복하였다. 최근 CORBA나 DCOM과 같은 분산 처리 기술과 객체지향 기법이 융화되어 생성된 컴포넌트 아키텍처는 고도의 재사용성이나 라이프타임의 증가뿐만 아니라 플러그-앤-플레이(Plug-&-Play)도 지원한다. 그러나 이러한 컴포넌트들을 조립하여 새로운 시스템을 구축하기 위해서는 컴포넌트의 구조와 인터페이스를 잘 정의한 명세서가 필요하다. 본 연구에서는 컴포넌트의 도입을 위한 참조 컴포넌트 아키텍처를 제시하고 UML을 이용한 이의 명세화에 대하여 제안한다.

• 한국지반환경공학회 논문집
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• 제12권11호
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• pp.5-12
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• 2011

연약지반은 지반강도가 낮으므로 공학적 문제점 개선방법에 대해 많은 연구가 수행되어 왔다. 대상현장은 연약지반의 압밀침하에 대해 안정성을 확보하기 위해 경량성토제인 EPS를 시공하였다. 그러나 포장층의 침하와 경계석의 파손 등 안정성에 문제점이 발생하였으며, 조사결과 현재높이가 설계높이보다 1m 이상 압축된 것으로 나타났다. 분석결과 상재하중에 영향을 받는 EPS가 설계 및 시공당시 상부 지반층 및 교통 하중이 과다하게 적용된 것으로 나타났다. 따라서 본 연구에서는 연약지반에 EPS가 시공된 현장의 고성토로 인한 문제점을 분석하고, 합리적인 대책공법을 제시한 사례를 소개함으로서 EPS 설계 및 시공 시 유의점을 제시하고자 한다.

• 대한임베디드공학회논문지
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• 제18권4호
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• pp.141-150
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• 2023

Currently, various companies are actively participating in research and development of drone delivery services. Existing studies do not comprehensively provide integrated functions for future drone delivery services such as mission automation, customer verification, and overcoming performance limitations, which can lead to high manpower demand, reduced user service trust, and potentially overloading low-end devices. Therefore, this study proposes a drone mission automation system (DMAS) using EdgeCPS technology to provide the three aforementioned functions in an integrated manner. Real-world experiments were conducted to evaluate the proposed system, demonstrating that the DMAS components operate according to the specified roles in the delivery scenario. In addition, the system achieved user verification with a similarity of more than 90% in the process of receiving the product, and verified a faster inference speed and a lower resource share than the existing method.

• Nuclear Engineering and Technology
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• 제55권3호
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• pp.1097-1104
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• 2023

A preliminary criticality analysis for novel pyrochemical apparatuses for the reprocessing of mixed uranium-plutonium nitride spent nuclear fuel from the BREST-OD-300 reactor was performed. High-temperature processing apparatuses, "metallization" electrolyzer, refinery remelting apparatus, refining electrolyzer, and "soft" chlorination apparatus are considered in this work. Computational models of apparatuses for two neutron radiation transport codes (MCU-FR and MCNP) were developed and calculations for criticality were completed using the Monte Carlo method. The criticality analysis was performed for different loads of fissile material into the apparatuses including overloading conditions. Various emergency situations were considered, in particular, those associated with water ingress into the chamber of the refinery remelting apparatus. It was revealed that for all the considered computational models nuclear safety rules are satisfied.