• Journal of Preventive Medicine and Public Health
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• 제46권1호
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• pp.39-49
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• 2013

Objectives: This study aims to investigate the prevalence of musculoskeletal symptoms and factors related to daily activities in a representative Korean population. Methods: This study was based on the questions about musculoskeletal symptoms in the Korean General Social Survey 2010. The questionnaire about musculoskeletal symptoms was adopted from Korean Occupational Safety and Health Agency guide, and it includes general characteristics, characteristics of pain, work type, work intensity and a 12-item Short Form Health Survey (SF-12). We utilized the criteria of the National Institute for Occupational Safety and Health to define the prevalence of musculoskeletal symptoms. Demographic, behavioral and socioeconomic factors were analyzed using logistic regression. Results: The prevalence of musculoskeletal symptoms was 38.3%. The prevalence was higher in females, the elderly, those without health insurance, and those with a low income, low education, and occupations with a heavy workload. The prevalence by body part was highest in the back, shoulder, and knee, in that order. The physical component summary and mental component summary of the SF-12 decreased with increasing musculoskeletal symptoms. Conclusions: Musculoskeletal symptoms are very common in the general population, and related to various socio-demographic factors. These results suggest that active prevention and management of musculoskeletal symptoms is needed at a national level.

• 한국정보처리학회논문지
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• 제7권11호
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• pp.3408-3416
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• 2000

본 논문에서는 독립변수들의 특징을 추출하여 패턴층 뉴런의 중앙값을 이용함으로써 일반회귀 신경망의 성능을 개선하는 방법을 제안하였다. 제안된 방법에서는 적응적 학습 알고리즘의 주요성분분석 기법을 이용하여 회귀분석에 이용되는 데이터의 각 독립변수들의 집합으로 변환시키는 특징을 살려 일반회귀 신경망의 성능을 더 개선하기 위함이다. 제안된 기법의 일반회귀 신경망을 2개의 독립변수 집합을 가진 Solow의 경제문제와 4개의 독립변수 집합을 가진 국내 유선전화문제에 각각 적용하여 시뮬레이션한 결과, 중심값을 각 독립변수들의 평균이나 가중평균을 이용하는 일반회귀 신경망에 의한 결과와 비교할 때 더욱 우수한 회귀성능이 있음을 확인할 수 있었다. 그리고 신경망의 뉴런 수나 평활요소의 설정 면에서도 우수한 특성이 있음을 확인할 수 있었다.

• 천문학논총
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• 제7권1호
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• pp.107-148
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• 1992

This paper presents a cosmological perturbation analysis in a Newtonian framework, using the Newtonian multi component version of the relativistic covariant equations. This work considers the fully nonlinear evolution of the perturbations, and is generalized to multicomponent systems and imperfect fluids. Known nonlinear solutions are presented in a general framework. Quasi-nonlinear analysis, considering both the compressible and rotational modes, is presented, including cases already known in the literature. The Fourier space representation of the conservation equations is also derived in a general context, with various decompositions of the velocity field. Commonly accepted cosmogonical frameworks are critically examined in the context of nonlinear evolution. This work may be regarded as the Newtonian counterpart of a recently presented general relativistic covariant formulation.

• 한국자동차공학회논문집
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• 제5권6호
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• pp.13-27
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• 1997

In the modern design technology, a component should be designed to fit into the overall system performance. A design methodology is developed to expedite the mechan- ical design of complex mechanical systems, The relation between the system design and component design is defined by a top-down approach and the results from the system design are utilized in the component design process. As a design example, an automobile exhaust system is selected for the system design and a bellows is chosen for a component design. Design methodology based on the top-down approach consists of five steps; (1) Analysis of service load, (2) Development of a lumped parameter, (3) Completion of the system design, (4) Selection of the component topology, (5) Completion of the component design, A method using a equivalent matrix is developed in order to determine unknown external forces in linear structural analyses. The bellows is also analyzed by the finite element method using a conical frustum shell element. Various experiments are performed to verify the developed theories. The top-down desi- gn approach is demonstrated by a design case using structural and shape optimization technology. Since the method is relatively simple and easy compared to other methods, it can be applied to the general design where system and component designs are involves simultaneously.

• 분석과학
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• 제32권4호
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• pp.131-138
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• 2019

This paper reports results on the physical properties of a powder type of $Al_2O_3:C$ commonly used as a luminescence dosimeter using the LM-OSL technique. On the analysis with the general order kinetics model, the LM-OSL signal measured appeared to be composed of three components (fast, medium, slow) showing the largest area in the medium component. The photoionization cross sections of three components were distributed between $10^{-19}{\sim}10^{-21}cm^2$. The values of the thermal assistance energy were evaluated the largest in slow component and the smallest in fast component, which indicates the electrons trapped in defects attributed to slow component should be the most sensitive to thermal vibration among three components. In illumination to blue light, the fast component showed a rapid linear decay and completely disappeared after light exposure time of about 5 s. The medium component decayed with two exponential elements but the slow component did not observed any noticeable change until light exposure time of 40 s. In a dose response study, all components exhibited a linear behaviour up to approximately 10 Gy.

• Journal of Preventive Medicine and Public Health
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• 제24권3호
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• pp.373-389
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• 1991

In order to develop the measuring tool of VDT syndrome and investigate the variables affecting the development of VDT syndrome, a questionnaire study accompanied with the evaluation of working environment was performed with 138 VDT users from six public organs in Kwangju area. The results were summarized as follows. 1. As a result of analysis with data collected by newly developed questionnaire, VDT syndrome included five factors named as eye-related component, psychological component, general body component, musculoskeletal component, and skin-related component and the estimates of the internal consistency of five factors were 0.877, 0.820, 0.796, 0.791, 0.593 respectively. 2. Variables affecting the level of eye-related symptoms were the type of main b using VDT, the total time of VDT operation per day, and the use of external filter on CRT. 3. The level of eye-related symptoms in the group using external filter was higher significantly than that in the group not using filter. 4. The past history of severe illness affected the level of psychological symptoms significantly. 5. Variables affecting the level of general body symptoms were b satisfaction and income satisfaction. 6. Variables affecting the level of musculoskeletal symptoms were the type of main job using VDT, whether majored in EDPS, the level of typewriting, b satisfaction, and the total time of VDT operation per day. 7. Age and the use of external filter were significantly related to the level of skin-related symptoms.

• Asian Pacific Journal of Cancer Prevention
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• 제15권2호
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• pp.695-701
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• 2014

The main objective of palliative treatment for cancer patients has been to maintain, if not improve, the quality of life (QoL). There is a lack of local data on satisfaction and QoL among cancer patients receiving palliative treatment in Malaysia. This study covers patients with incurable, progressive cancer disease receiving palliative treatment in a teaching hospital in Kuala Lumpur, comparing the different components of QoL and correlations with patient satisfaction. A cross-sectional survey using Malay validated SF36 QoL and PSQ-18 (Short Form) tools was carried out between July 2012 -January 2013 with 120 cancer patients receiving palliative treatment, recruited into the study after informed consent using convenient sampling. Results showed that highest satisfaction were observed in Communication Aspect ($50.6{\pm}9.07$) and the least in General Satisfaction ($26.4{\pm}5.90$). The Mental Component Summary ($44.9{\pm}6.84$) scored higher when compared with the Physical Component Summary ($42.2{\pm}7.91$). In this study, we found that patient satisfaction was strongly associated with good quality of life among cancer patients from a general satisfaction aspect (r=0.232). A poor significant negative correlation was found in Physical Component (technical quality, r=-0.312). The Mental Component showed there was a poor negative correlation between time spent with doctor (r=-0.192) and accessibility, (r=-0.279). We found that feeling at peace and having a sense of meaning in life were more important to patients than being active or achieving good physical comfort. More studyis needed to investigate patients who score poorly on physical and mental component aspects to understand their needs in order to achieve better cancer care.

• 한국컴퓨터정보학회논문지
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• 제13권7호
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• pp.127-138
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• 2008

무기체계 연구개발 프로세스를 위한 형상/정보관리시스템은 오랜 연구개발 과정에서 생산되는 문서, 도면, 구성품정보, 구조정보 등에 대한 동시공학 및 협업적 업무를 지원해야 한다. 본 논문에서는 웹 환경에서 운영되는 무기체계 연구개발 형상/정보관리시스템을 구현하기 위한 CBD (Component Based Development) 개발 및 모델링 방법론에 관한 논문으로서 기존의 연구에서는 일반적인 MVC 모델을 사용한 3계층의 시스템 아키텍처를 구성하는 반면 본 논문에서는 J2EE 환경하의 EJB 구조를 기반으로 한 4계층 시스템 아키텍처를 정의하였다. 본 논문에서는 4계층 시스템 아키텍처를 통하여 모델 계층과 제어 계층을 각각 두 단계로 세분화하여 컴포넌트의 속성을 구체화할 수 있는 방안을 제시하였으며, 컴포넌트 기반으로 시스템 개발 업무를 수행하여 각 개발 단계별 표현 모델에 대한 시스템 결과물을 산출하여 실제 시스템을 구현하였다.

• 전기학회논문지
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• 제64권11호
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• pp.1543-1550
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• 2015

Ferroresonance is a non-linear vibrational phenomenon that is generated by the electrical interaction of the inductance component with the capacitor component of a certain capacitance as the device of the inductance component such as a transformer is saturated due to the degradation, the waveform distortion of current and voltage, and the oscillation of overcurrent and overvoltage in a system. Recently, ferroresonance was generated from the waveform distortion of current and voltage, or the overvoltage or undervoltage phenomenon caused by the nature of an electrical power system and design technology of the transformer in the three phase transformer system. Hence, in general, ferroresonance analyzed by converting to the LC equivalent circuit. However, in general, the aforementioned analytical method only applies to the resonance phenomenon that is generated by the interaction of the capacitance of bussbar and grounding, and switching as the capacitor component with PT and the transformer as the inductance component in a system. Subsequently, the condition where ferroresonance was generated since overvoltage was supplied as line voltage to the phase voltage and thus the iron core is saturated due to the interconnection between grounded and ungrounded systems could not be analyzed when single phase PT was connected in a ${\Delta}$/Y connection system. In this study, voltage swell in the configuration of grounded circuit of a step-up transformer with the ${\Delta}-{\Delta}$ connection linked to PT for control power and the ferroresonance generated by overvoltage when the line voltage of the ${\Delta}-{\Delta}$ connection was connected to the phase voltage of the grounded Y-Y connection were analyzed using PSCAD / EMTDC through the failure case of the transformer caused by ferroresonance in the system with the ${\Delta}-{\Delta}$/Y-Y connection, and subsequently, the preventive measure of ferroresonance was proposed.

• 소프트웨어공학소사이어티 논문지
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• 제25권1호
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• pp.11-18
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• 2012

원자력 시설 해체 사업은 해체 시 방사성 물질이 발생하기 때문에 시설 해체에 있어서 일반적인 해체 공법을 사용하기 어렵다. 그렇기 때문에 원자력 시설의 해체 계획을 수립하는데 해체 대상시설의 성격을 조사하고 파악하는 것이 매우 중요하며 해체 대상 원자력 시설의 특성 자료 조사는 해체 폐기물의 양을 예측하고 해체 사업의 비용 산정에 크게 활용이 된다. 한국원자력연구원에서는 이를 목적으로 해체사업 대상 시설의 특성자료를 관리하는 시스템 DEFACS(Decommissioning Facility Characterization DB System)을 개발하였다. 그러나 원자력 시설 해체에는 시간이 오래 걸리기 때문에 부득이하게 해체 사업 중에 시스템을 개발하였고 이는 지속적인 요구사항의 변경이 발생하는 원인이 되었다. 이러한 이유로 개발에 있어서 일반적인 개발 프로세스를 적용키 어려웠던 바, 본 논문에서는 개발 중 요구사항 변경에 대한 효율적인 대응을 하기 위하여 기존의 CBD(Compoenent Based Development) 프로세스를 CD(Component Development)와 CBSD(Component Based Software Development)로 구분하여 변경사항에 대한 핸들링을 하나의 컴포넌트로 다루고 컴포넌트 별로 CBD를 재적용하여 재귀적으로 프로세스를 핸들링한다. 이로써 컴포넌트 변경에 대한 전체 시스템의 변경점을 최소화하고 컴포넌트와 프로세스의 독립성을 강화함으로써 요구사항 변경으로 인한 프로세스의 중지를 최소화 하였다.