• Wind and Structures
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• 제9권4호
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• pp.255-270
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• 2006

Several analytical procedures available in literature, for the evaluation of wind induced fatigue damage of structures, either assume the wide band random stress variations as narrow band random process or use correction factors along with narrow band assumption. This paper compares the correction factors obtained using the Rainflow Cycle (RFC) counting of the measured stress time histories on a lamp mast and a lattice tower, with those evaluated using different frequency domain methods available in literature. A Bi-modal spectral method has been formulated by idealising the single spectral moment method into two modes of background and resonant components, as considered in the gust response factor, for the evaluation of fatigue of slender structures subjected to "along-wind vibrations". A closed form approximation for the effective frequency of the background component has been developed. The simplicity and the accuracy of the new method have been illustrated through a case study by simulating stress time histories at the base of an urban light pole for different mean wind speeds. The correction factors obtained by the Bi-modal spectral method have been compared with those obtained from the simulated stress time histories using RFC counting method. The developed Bi-modal method is observed to be a simple and easy to use alternative to detailed time and frequency domain fatigue analyses without considerable computational and experimental efforts.

• Structural Engineering and Mechanics
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• 제28권5호
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• pp.525-548
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• 2008

This article deals the theory for solving an inverse problem of plate structures using the frequency-domain information instead of classical time-domain delays or free vibration eigenmodes or eigenvalues. A reduced set of output parameters characterizing the defect is used as a regularization technique to drastically overcome noise problems that appear in imaging techniques. A deconvolution scheme from an undamaged specimen overrides uncertainties about the input signal and other coherent noises. This approach provides the advantage that it is not necessary to visually identify the portion of the signal that contains the information about the defect. The theoretical model for Quantitative nondestructive evaluation, the relationship between the real and ideal models, the finite element method (FEM) for the forward problem, and inverse procedure for detecting the defects are developed. The theoretical formulation is experimentally verified using dynamic responses of a steel plate under impact loading at several points. The signal synthesized by FEM, the residual, and its components are analyzed for different choices of time window. The noise effects are taken into account in the inversion strategy by designing a filter for the cost functional to be minimized. The technique is focused toward a exible and rapid inspection of large areas, by recovering the position of the defect by means of a single accelerometer, overriding experimental calibration, and using a reduced number of impact events.

• 대한전기학회논문지:시스템및제어부문D
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• 제54권5호
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• pp.338-347
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• 2005

A computer-based low back muscle evaluation system was designed to simultaneously acquire, process, display, quantify, and correlate electromyographic(EMG) activity with muscle force, and range of motion(ROM) in the lumbar muscle of human. This integrated multi-channel system was designed around notebook PC. Each channel consisted of a time and frequency domain block, and T-F(time-frequency) domain block. The captured data in each channel was used to display and Quantify : raw EMG, histogram, zero crossing, turn, RMS(root mean square), variance, mean, power spectrum, median frequency, mean frequency, wavelet transform, Wigner-Ville distribution, Choi-Williams distribution, and Cohen-Posch distribution. To evaluate the performance of the designed system, the static and dynamic contraction experiments from lumbar(waist) level of human were done. The experiment performed in five subjects, and various parameters were tested and compared. This system could equally well be modified to allow acquisition, processing, and analysis of EMG signals in other studies and applications.

• 한국교육논총
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• 제38권1호
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• pp.29-39
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• 2017

본 연구는 2009 개정 과학과 교육과정에 근거한 중학교 과학 교과서의 산염기 및 산화 환원 단원의 문항을 블룸의 교육목표 분류틀을 이용하여 분석한 것이다. 분석 결과 모든 출판사의 교과서 문항에서는 지식 영역의 요소가 가장 많이 나타났으며, 이해, 적용, 분석, 종합, 평가 순으로 그 요소는 적게 나타났다. 그리고 출판사에 따라 각 문항에 나타난 인지 영역의 하위 영역이 골고루 포함되지 않았다. 그래서 학교에서는 다양한 출판사의 교과서 단원평가 문항을 참조하여 수업에 이용할 필요가 있다.

• Child Health Nursing Research
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• 제10권2호
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• pp.165-172
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• 2004

The main purpose of this study is to examine the concepts appeared on research and provide future research directions in field of child health nursing. 205 studies of the total 318 studies had been analyzed first for the concepts of the client domain and this time 113 studies were analyzed for the practice, the client-nurse and the environmental domain in nursing. The practice domain includes mentalistitic, enactment, knowledge utilization, role related phenomenon, the client-nurse domain includes touch, communication, interaction phenomenon, and the environmental domain includes physical, social, symbolic environment. All were originally published between 1990 and 2000 in Korea. An analysis of concepts for this study was used the metaparadigm framework for nursing proposed by H. S. Kim(2000). 1. 103 studies belonged to the practice domain. Among them, 56(54％) studies used concepts related to enactment phenomenon like education(21.4％), giving information(7.1％), breast feeding(5.4％), caring(5.4％), airway suction(5.4％), nonnutritive sucking(5.4％). 44(43％) studies used concepts related to knowledge utilization like program development and evaluation of smoking, mother-infant interaction, home health nursing, obesity management. And only 3(3％) studies used role related concepts like quality of nursing, direction of health education, contents of child health nursing education. 2. Only 2(0.006％) studies belonged to the client-nurse domain. One concept is empathy in communication phenomenon and the other concept is role conflict in interaction phenomenon. 3. 8(0.02％) studies belonged to the environmental domain. Among them, 3 studies related to physical environment like space, noise and 5 studies related to social environment like social support, home environment. But the concept of symbolic environment was not used. The findings of this study provide the evidence that research related to the client-nurse domain and the environmental domain should be conducted actively to improve the practice of child health nursing. So that the research in field of child health nursing should be dealt with the concepts of four domains to develop knowledge systematically.

• Nutrition Research and Practice
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• 제6권6호
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• pp.542-550
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• 2012

This pilot study was performed to produce data of the Children's Dietary Life Safety (CDLS) Index which is required by the Special Act on Safety Management of Children's Dietary Life and to evaluate the CDLS Index for 7 metropolitan cities and 9 provinces in Korea. To calculate the CDLS Index score, data regarding the evaluation indicators in the children's food safety domain and children's nutrition safety domain were collected from the local governments in 2009. For data regarding the indicators in the children's perception & practice domain, a survey was conducted on 2,400 5th grade children selected by stratified sampling in 16 local areas. Relative scores of indicators in each domain were calculated using the data provided by local governments and the survey, the weights are applied on relative scores, and then the CDLS Index scores of local governments were produced by adding scores of the 3 domains. The national average scores of the food safety domain, the nutrition safety domain and the perception and practice domain were 23.74 (14.67-26.50 on a 40-point scale), 16.65 (12.25-19.60 on a 40-point scale), and 14.88 (14.16-15.30 on a 20-point scale), respectively. The national average score of the CDLS Index which was produced by adding the scores of the three domains was 55.27 ranging 46.44-58.94 among local governments. The CDLS Index scores produced in this study may provide the motivation for comparing relative accomplishment and for actively achieving the goals through establishment of the target value by local governments. Also, it can be used as useful data for the establishment and improvement of children's dietary life safety policy at the national level.

• 한국터널지하공간학회 논문집
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• 제11권1호
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• pp.71-83
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• 2009

숏크리트는 터널에서 적용되는 요요한 주지보재이다. 숏크리트의 품질평가는 터널의 안전한 시공과 효과적인 운영을 위한 핵심 요소이다. 숏크리트가 암반에 적절히 타설되었다 하더라도, 막장 및 벤치부에서의 발파, 수축, 지반의 변형 등으로 인해 숏크리트 균열발생 및 배면공동 등의 문제를 야기한다. 본 논문에서는 비파괴 시험인 충격 반항 기법(Impact-Echo) 및 지하레이다 탐사(GPR)를 이용하여 경임에 타설된 숏크리트 배면의 접착상태를 평가하고자 하였다. 기존의 수치해석 연구에 대한 검증과 더불어 현장 적용성에 대한 검토를 위해 실험적 연구를 수행하였다. 숏크리트의 접착상태는 완전 접착, 접착력 상실 및 공동 조건으로 구분할 수 있다. 실내 실대형 시험체에 이 세 가지 숏크리트 접착상태를 조사하였다. 충격반향시험으로부터 획득된 신호는 시간영역, 주파수 영역, 및 시간-주파수 영역에서 각각 분석되었다. 능동적 신호 처리 기법인 Short-Time Fourier Transform(STFT)을 이용하여 숏크리트 배면의 접착상태를 효과적으로 예측할 수 있었으며, 그 결과는 기존의 수치해석 연구로부터 획득한 신호특성과 잘 부합하였다. 숏크리트 배면의 접착상태가 불량할수록 다음과 같은 특징들을 나타낸다. 즉, 주파수 영역에서 자기스펙트럼밀도가 커지며, 기하학적 감쇠비는 감소하고, 시간-주파수 영역에서 윤곽선은 시간축에 평행한 형상을 나타내며, 숏크리트 두께가 얇을수록 그 공진시간이 길어진다. 또한 본 연구에서 제시한 상관계수를 이용하여 숏크리트의 접착상태를 정량적으로 평가할 수 있다. 본 연구 결과를 바탕으로 숏크리트의 접착상태를 평가할 수 있는 평가 기법 및 평가 기준을 제안하였다.

• 한국치위생학회지
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• 제19권4호
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• pp.479-492
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• 2019

Objectives: This study aimed to develop the CAMBRA-kids application for the systematic management of dental caries among preschoolers, activate the dental caries management system, and contribute to the dental caries management of preschoolers. Methods: The collected data were analyzed using R studio 1.2.1335 for Windows (RStudio Inc., Boston, MA, USA, 2018). Algorithm evaluation, heuristic evaluation and usability evaluation were analyzed using descriptive statistics. Results: Both expert evaluations of the application's algorithms were calculated as 100%, for proficiency and efficiency. The application worked well with the designed algorithms, the risk group level of participants was categorized appropriately, and the risk management method was guided properly according to the risk group level. Of the five problems presented in the heuristic evaluation, 'the lack of security' and 'the lack of information on oral health care' received 'high severity' scores. The usability evaluation of the application produces an overall score of 3.27. In the subscales (participation, functionality, aesthetics, and information) of the Mobile App Rating Scale (MARS), the 'participation' domain received the lowest score of 2.56 and the 'functional' domain received the highest score of 3.70. Conclusions: The CAMBRA-kids application is expected to be applied and used in the field of preschoolers' oral health care management, and to contribute to the prevention of dental caries of preschoolers by activating the dental caries management system using the application.

• 한국정보통신학회논문지
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• 제18권1호
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• pp.149-154
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• 2014

품질은 양(Quantity) 이나 질(Quality)로 관찰하여 수치로 측정 할 수 있는 서비스 특성이다. QoS란 트래픽이 통신망에서 전달되면서 예측 가능하면서 동시에 최소한으로 보장되어야할 서비스 요구사항이다. 스마트 의료정보시스템 개발에는 스마트 환경에서 기능적 요구사항과 품질을 만족시켜야 할 목표가 존재한다. 스마트 의료정보시스템의 기능도메인은 Patient Module 도메인, 스마트 환경 도메인, RFID Tag와 리더기 간 동작 도메인, Homecare Station 도메인, Clinical Station 도메인으로 구성된다. 본 연구는 각 도메인에서 수행되는 유헬스 서비스 스마트 기능 품질만족도 평가 방법론을 제시한다. QoS 측정기준은 의료정보의 기능적 요구 사항과 품질 요구사항 별로 구분된다. 품질측정 파라메타는 기능적 요구사항 6개 항목과 20개 세부항목이며 품질 요구사항은 5개항목과 20개 세부항목으로 구성된다. 품질평가를 위해 본 연구는 한국형 스마트 의료 정보 품질평가 매트릭스로 2-factor 평가 방법을 제시한다. 본 연구의 전체적인 품질평가 프레임워크는 모든 스마트 의료정보시스템 개발 시 고려해야 할 의료정보 특유의 품질에 대한 기준을 체계화하고 품질평가 절차를 모델화 한 것이다.

• 감성과학
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• 제13권4호
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• pp.669-676
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• 2010

조절부합은 개인의 조절초점 성향과 평가 및 판단 전략이 지닌 조절초점이 서로 일치할 때 일어난다. 본 연구에서는 평가 및 의사결정의 영역이 유발하는 조절초점과 개인의 조절초점간의 부합이 평가에 영향을 미칠 것이라고 가정하고, 향상적 영역으로는 제품 디자인 평가를, 예방적 영역으로는 도덕적 평가를 사용하여 조절부합 효과를 알아보았다. 향상초점과 관련된 영역인 미적 제품에 대한 평가 과제를 사용한 실험 1에서는 향상초점인 사람들이 예방초점인 사람들에 비해 긍정적인 것은 더 긍정적으로, 부정적인 것은 더 부정적으로 평가하였다, F(1, 95) = 4.87, p < .05. 반면 금지와 규범적인 도덕 상황을 사용한 실험 2에서는 금지적 상황에서만 예방초점인 사람들이 향상초점인 사람들에 비해 도덕적으로 옳지 않은 결정에 대해서는 더 비 도덕적인 것으로 평가하였다, F(1, 139) 4.14, p < .05. 반면 규범적 상황에 대한 평가에서는 이러한 조절부합 효과가 나타나지 않았다. 이러한 연구결과는 평가 및 의사결정 영역과 관련해서도 조절부합이 나타날 수 있음을 보여준다.