• 한국멀티미디어학회논문지
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• 제9권8호
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• pp.1076-1085
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• 2006

다양한 요구 사항들을 완전하게 만족시켜 주기 위한 컴포넌트의 설계는 매우 어려우며 또한 도메인의 특정화된 업무 로직을 완전하게 수용하는 것은 불가능하다. 이러한 요구 사항을 만족시키기 위해 블랙 박스보다는 화이트 박스 컴포넌트로 제공될 필요가 있다. 본 논문에서는 다양한 도메인의 요구사항을 수용할 수 있는 장치를 제공하기 위해 컴포넌트의 가변성 설계 기법과 이런 설계 기법을 이용하여 컴포넌트를 커스터마이제이션 하기 위한 기법을 제안한다. 컴포넌트의 가변성은 컴포넌트 개발 과정에서 초기 가변성이 설계되며 가변성 적용을 위해 커스터마이제이션 기법을 이용한다. 본 논문에서는 컴포넌트의 기능 변경을 위한 행위 가변성 설계 기법과 커스터마이제이션 기법을 제안한다. 가변성이 적용된 컴포넌트는 이를 기반으로 한 어플리케이션을 개발하는 과정에서 가변성이 재설계될 수 있으며 이러한 과정을 통해 컴포넌트의 가변성이 진화되고 컴포넌트의 일반성이 더욱 향상될 수 있다.

• 대한기계학회논문집A
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• 제23권7호
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• pp.1164-1172
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• 1999

In this study, to investigate the fatigue crack retardation behavior and the variability of retardation cycles, fatigue crack growth tests were conducted on 7075-T6 aluminum alloy under single tensile overload. A retardation coefficient, D was introduced to describe fatigue crack retardation behavior and a random variable, Z to describe the variability of fatigue crack growth. The retardation coefficient was separately formulated according to retardation behavior which is composed of delayed retardation part and retardation part. The random variable, Z was evaluated from experimental data which was obtained from fatigue crack growth tests under constant amplitude load. Using these variables, a probabilistic model was developed on the basis of the modified Forman's equation, and retardation behavior and cycles were predicted under certain overload condition. The predicted retardation curve well agrees with the trend of experimental crack retardation behavior. And this model well predicts the scatter of experimental retardation cycles.

• 한국한의학연구원논문집
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• 제13권3호
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• pp.97-103
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• 2007

The object of this study is to evaluate confounding effect of sleeping behavior on heart rate variability (HRV) in healthy volunteers during a randomized clinical trial. From 6 healthy volunteer, we acquired circadian electrocardiography(ECG) with a Holter monitoring device(DigiTrak Plus, Philips). The compatible analytical program, Zymed, was used for calculation of RR intervals of 24h ECG signal. Then, we generated HRV signals and calculated 9 HRV parameters in time domain and frequency domain for every 30 minute with Matlab 6.x software. We also encoded participants' activities as follows; stable condition(1), sleeping behavior(2), eating behavior(3), and undefined condition(4). Using SPSS 12.0, we tested if there was any difference between HRV parameters of day-time and night-time and between those of a subject in stable condition and in sleeping behavior. As a result, one of the most important parameter-LF/HF ratio, which indicates the autonomic balance between sympathetic and parasympathetic nervous systems, as same the other parameters, showed large inter-individual variations in circadian profiles. And, the mean LF/HF ratio of each participant was different between in stable condition and in sleeping behavior (p<.05). Consequently, the effect of sleeping behavior must be considered when one or more of HRV parameters, especially LF/HF ratio, are used as assessment index in clinical studies.

• 한국정보과학회논문지:소프트웨어및응용
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• 제30권3_4호
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• pp.185-201
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• 2003

다양한 도메인의 요구사항을 만족시켜 주기 위한 비즈니스 컴포넌트(Business Component)는 다양성을 제공할 수 있도록 개발되어야 한다. 그러나 컴포넌트 개발 시에 다양한 요구사항을 분석하여 개발되더라도 컴포넌트가 이용될 때 예상하지 못한 요구 사항들이 발생하기 때문에 요구 사항들을 완전하게 만족시켜 주기 위한 컴포넌트의 개발은 쉽지 않다. 이와 같은 이유 때문에 컴포넌트가 블랙 박스가 아닌 화이트 박스로 제공되므로 컴포넌트를 인터페이스에 의해 변경하는 것이 아니라 직접 코드를 변경하는 문제가 발생한다. 따라서 컴포넌트를 이용한 Time-To-Market을 이루기가 쉽지 않으며 컴포넌트의 재사용성도 떨어진다. 본 논문에서는 컴포넌트의 변경 가능한 부분을 분석하여 다양한 요구 사항을 만족시킬 수 있는 커스터마이제이션 기법을 제안한다. 컴포넌트의 초기 가변성은 컴포넌트 개발(CD : Component Development) 과정에서 설계되며 가변성 적용을 위해 커스터마이제이션 기법을 이용한다. 가변성이 적용된 컴포넌트를 이용하여 어플리케이션을 개발하는 과정에서 가변성이 재 설계될 수 있으며 이러한 과정을 통해 컴포넌트의 가변성은 진화하고 컴포넌트의 일반성은 향상될 수 있다. 본 논문에서 제시하는 커스터마이제이션 기법은 컴포넌트가 재 설계될 때 기존 컴포넌트는 전혀 변경하지 않고 확장하여 컴포넌트를 변경 할 수 있다.

• 정보처리학회논문지D
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• 제9D권5호
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• pp.837-846
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• 2002

컴포넌트 개발 시에 속성과 행위에 대한 공용성과 가변성을 분석하여 재사용과 확장성을 제공할 수 있다. 그러므로 공용성과 가변성이 분석된 컴포넌트는 기능과 적합성의 불일치를 줄이고자하는 목적에서 사용하게 된다 본 논문에서는 영역에 의하여 존재하는 컴포넌트의 공용성과 가변성을 분석해서, 컴포넌트의 기능을 행위분석에 의하여 추출하였다. 이와 같은 분석에 의하여 컴포넌트의 재사용과 확장성을 연구하고자 한다.

• Earthquakes and Structures
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• 제12권2호
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• pp.165-175
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• 2017

This paper studies soil properties uncertainty and its implementation in the seismic response evaluation of structures. For this, response sensitivity of two 4- and 12-story RC shear walls to the soil properties uncertainty by considering soil structure interaction (SSI) effects is investigated. Beam on Nonlinear Winkler Foundation (BNWF) model is used for shallow foundation modeling and the uncertainty of soil properties is expanded to the foundation stiffness and strength parameters variability. Monte Carlo (MC) simulation technique is employed for probabilistic evaluations. By investigating the probabilistic evaluation results it's observed that as the soil and foundation become stiffer, the soil uncertainty is found to be less important in influencing the response variability. On the other hand, the soil uncertainty becomes more important as the foundation-structure system is expected to experience nonlinear behavior to more sever degree. Since full This paper studies soil properties uncertainty and its implementation in the seismic response evaluation of structures. For this, response sensitivity of two 4- and 12-story RC shear walls to the soil properties uncertainty by considering soil structure interaction (SSI) effects is investigated. Beam on Nonlinear Winkler Foundation (BNWF) model is used for shallow foundation modeling and the uncertainty of soil properties is expanded to the foundation stiffness and strength parameters variability. Monte Carlo (MC) simulation technique is employed for probabilistic evaluations. By investigating the probabilistic evaluation results it's observed that as the soil and foundation become stiffer, the soil uncertainty is found to be less important in influencing the response variability. On the other hand, the soil uncertainty becomes more important as the foundation-structure system is expected to experience nonlinear behavior to more sever degree. Since full probabilistic analysis methods like MC commonly are very time consuming, the feasibility of simple approximate methods' application including First Order Second Moment (FOSM) method and ASCE41 proposed approach for the soil uncertainty considerations is investigated. By comparing the results of the approximate methods with the results obtained from MC, it's observed that the results of both FOSM and ASCE41 methods are in good agreement with the results of MC simulation technique and they show acceptable accuracy in predicting the response variability.

• 한국학교보건학회지
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• 제30권3호
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• pp.266-273
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• 2017

Purpose: This study was performed to compare the mental health of school age children residing in urban and rural areas and to analyze the correlations between the subjective mental health indicators such as depression and attention deficit-hyperactivity behavior and heart rate variability (HRV) indicators. Methods: For this study, a convenience sample of one hundred and three children was recruited. Depression and attention deficit-hyperactivity behavior were measured using self-reported questionnaires and HRV indicators were measured using an electronic instrument. Results: Among the HRV parameters of the rural children, their normalized LF and the LF / HF were significantly lower than those of the urban children. The RMSSD and the normalized HF were statistically significantly higher. The level of depression showed a significant positive correlation with the normalized LF and LF/HF, but showed a negative correlation with the normalized HF. Also, the level of attention deficit-hyperactivity behavior was significantly correlated with the normalized LF, LF/HF, and the normalized HF. Conclusion: Based on the findings, we expect that HRV indicators can be applied to predict the level of depression and attention deficit-hyperactivity behavior in elementary school children.

• Animal Bioscience
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• 제37권5호
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• pp.944-951
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• 2024

Objective: Parturition is crucial for dams, their calves, and cow managers. The prediction of calving time, which assists cow managers to decide on the relocation of cows to maternity pens and necessity of human supervision, is a pivotal aspect of livestock farming. However, existing methods of predicting calving time in dairy cows based on hormonal changes and clinical symptoms are time-consuming and yield unreliable predictions. Accordingly, we investigated whether heart rate variability (HRV) which is a non-invasive assessment of autonomic nervous system (ANS) activity and behavior during the prepartum period would be useful for predicting calving time in dairy cows. Methods: Eight pregnant cows were surveilled under electrocardiogram and video recordings for HRV and behavioral analyses, respectively. HRV parameters in time and frequency domains were evaluated. A 24-h time budget was calculated for each of six types of behavior (standing and lying with or without rumination, sleeping, and eating). Results: Heart rate on calving day is considerably higher than those recorded on the days preceding calving. Low frequency power declined, whereas high frequency power escalated on the calving day compared to the period between 24 and 48 h before calving. The time budget for ruminating while lying decreased and that while standing increased markedly on the calving day compared to those allocated on the preceding days; nonetheless, the total time budget for ruminating did not differ during the prepartum period. Conclusion: We elucidated the ANS activity and behavioral profiles during prepartum period. Our results confirm that HRV parameters and behavior are useful for predicting calving time, and interestingly indicate that the time budget for ruminating while standing (or lying) may serve as a valuable predictor of calving. Collectively, our findings lay the foundation for future investigations to determine other potential predictors and formulate an algorithm for predicting calving time.

• 대한기계학회논문집A
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• 제24권8호
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• pp.2074-2082
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• 2000

In this study, to investigate and to predict the crack growth behavior under variable amplitude loading, crack growth tests are conducted on 7075-T6 aluminum alloy. The loading wave forms are generated by normal random number generator. All wave forms have same average and RMS(root mean square) value, but different standard deviation, which is to vary the maximum load in each wave. The modified Forman's equation is used as crack growth equation. Using the retardation coefficient D defined in previous study, the load interaction effect is considered. The variability in crack growth process is described by the random variable Z which was obtained from crack growth tests under constant amplitude loading in previous work. From these, a statistical model is developed. The curves predicted by the proposed model well describe the crack growth behavior under variable amplitude loading and agree with experimental data. In addition, this model well predicts the variability in crack growth process under variable amplitude loading.

• 대한토목학회논문집
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• 제26권4B호
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• pp.329-334
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• 2006

Southern Great Plain 1999 실험을 통하여 획득된 L-band와 C-band 토양수분 측정치의 공간 변화 양상을 분석하였다. L-band 토양수분 측정치의 스펙트럼은 관측 스케일의 변화와 함께 토양수분의 공간 변화 양상이 변화됨을 보여주었고, 이러한 변화 양상은 모래함유비와 같은 토양 특성의 공간 변화 양상과 일치함을 보여주었다. 그리고 C-band 토양수분 측정치의 공간 변화 양상은 관측 스케일의 변화와 상관없이 일정한 변화도를 가지는 것으로 나타났다. 이는 식생피복의 공간 변화 양상과 동일함을 보여주는 것이다. 이러한 결과는 AMSR기기를 이용하여 현재 진행되고 있는 토양수분의 전 지구 관측치의 downscaling시 고려되어야 할 것이다.