• Title/Summary/Keyword: time-dependence

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Behavioral Analysis of Dynamic Route Choice with Stated Preference Panel Data (선호의식 Panel Data를 이용한 동적 경로선택 행동분석)

  • 성수련;남궁문
    • Journal of Korean Society of Transportation
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    • v.17 no.3
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    • pp.47-60
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    • 1999
  • In this study, the dynamic route choice behavior of driver is assumed to be affected by the current conditions of traffic environments as well as the Past traffic environments and activities. The repeated survey of multi-timed to owner drove in Chon-ju city by the virtual traffic information system was performed by the stated preference method. And the LISREL(An analysis of linear structural relationship) model was used. As the results. the variable Parameter and t-value of travel time information on applied model was high and their results have an effect greatly to the route choice. After all, the route choice was negative from Kirin-ro, which Penetrates the downtown, and positive from Chunbyun-ro which was a roundabout way was confirmed. Estimated result of the reasonability, the highest suitable model was ode which applied the concept of serial correlation and stated dependence and was shown applying rightfulness to dynamic model. As the serial correlation and stated dependence parameter value, when time interval was large, parameter value was small and the serial correlation and stated dependence was in inverse proportion ratio to the time interval.

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Analysis on the Transition and Determinants of Long-Term Care Service for the Elderly in the Internet of Things era (융합의 시대에(사물인터넷시대에)한국 노인의 장기요양 서비스 이용 상태 전환과 결정요인 분석)

  • Choi, Jang-Won
    • Journal of Internet of Things and Convergence
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    • v.6 no.4
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    • pp.39-48
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    • 2020
  • This study intends to the estimate the determinants and state dependence of long-term care services in Korea. For this purpose, we analyzed the transition patterns among three states of long-term care service utilization over time by using the Korea Welfare Panel Study data with the random effect multinomial logit model. It is found that the result showed a strong state dependence in long-term care service utilization. Especially, long-term care insurance for the elderly showed a strong state dependence among others. Among the individual demographic characteristics, the higher the age, the higher the probability of using long-term care insurance for the elderly, while the lower the probability when married. The characteristics of the residential region showed that the residents of the urban-rural integrated region had a significantly higher probability of using long-term care insurance than the reference region. The results of this study suggest that the long-term care service users have a strong state dependence, which means that it is important to take into account the increase in the utilization period of existing users in future demand forecasting.

Characteristics of Eating Behavior in Elders with Dementia residing in Long-Term Care Facilities (장기 요양 시설 거주 치매노인의 식사행동 특성)

  • Lee, Kyoung-Min;Song, Jun-Ah
    • Journal of Korean Academy of Nursing
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    • v.42 no.4
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    • pp.466-476
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    • 2012
  • Purpose: The purpose of this study was to explore characteristics of eating behavior according to level of functional status of elders with dementia (EWD), and to examine feeding time, change in food intake and body mass index (BMI) according to eating behavior. Methods: Participants were 149 EWD residing in long-term care facilities located in Seoul or Gyeonggi province and evaluated using the Mini-Mental State Exam-Korean version, Korean version-Activities of Daily Living, and Eating Behavior Scale (EBS). Feeding time, change in food intake, and BMI were also measured. Data were analyzed using SPSS 17.0, specifically descriptive statistics, ANOVA, and Chi-square test. Results: Participants' mean EBS score was $10.43{\pm}6.01$ and half of them (54.4%) needed moderate or total assistance while eating. The EBS score was significantly lower for elders with severe dementia compared to those with mild or moderate dementia; and elders with severe ADL dependence compared to those with mild or moderate ADL dependence. Lower EBS scores were related to longer feeding time, a greater the rate of participants with decreased food intake and 'underweight' BMI. Conclusion: Nursing intervention programs which are designed for EWD are needed to maintain functional eating skills and prevent negative consequences in this population.

Free Vibration Analysis of Annular Sector Plates Using Time Average Holographic Interferometer (시간평균 홀로그래픽 간섭계를 이용한 환형 평판의 자유 진동 연구)

  • 나종문
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.3
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    • pp.353-361
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    • 1998
  • The study on the vibration characteristics of annular sector plates is important for structural engineers. In this study the vibration modes and their natural frequencies of annular sector plates clamped along the inner circumferential edge are obtained by the time average holographic interferometer according to the varying sector angle. The experimental results agree well with those obtained by the numerical analysis. The vibration characteristics of annular sector plates shows great dependence on the sector angle. The radial nodal lines converge to the center of annular sector plate.

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Size Refinement of Empirical Likelihood Tests in Time Series Models using Sieve Bootstraps

  • Lee, Jin
    • Communications for Statistical Applications and Methods
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    • v.20 no.3
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    • pp.199-205
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    • 2013
  • We employ sieve bootstraps for empirical likelihood tests in time series models because their null distributions are often vulnerable to the presence of serial dependence. We found a significant size refinement of the bootstrapped versions of a Lagrangian Multiplier type test statistic regardless of the bandwidth choice required by long-run variance estimations.

Time-Domain Numerical Investigation of Ring Resonator Optical Delay Devices

  • Chung, Youngchul
    • Journal of the Optical Society of Korea
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    • v.17 no.5
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    • pp.441-446
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    • 2013
  • A split-step time-domain model for the analysis of pulse delay characteristics through ring resonator all-pass filters (APF's) is developed and its accuracy is checked. The dependence of the delay time and pulse distortion on the coupling ratios is investigated using the model. It is observed that the bandwidth of the APF's needs to be wide enough to minimize the pulse distortion.

Analysis of internet self-similar traffic through the round-trip time measurement (Round-Trip Time 측정을 통한 인터넷 트래픽의 자기 유사성 분석)

  • 황인수;송기평;이동철;박기식;김창호;김동일;최삼길
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 1999.11a
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    • pp.326-330
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    • 1999
  • 인터넷의 민감한 트래픽 특성으로 인해 기존의 트래픽 모델링 분석법으로 최적화된 네트워크 환경을 구성하기에는 부족한 점이 많다. 본 논문에서는 트래픽의 버스트 특성을 정확히 예측하고 모델링 하기 위한 방법으로 자기 유사 특성에 대해 분석하고자 한다. 실제 인터넷 네트워크에서의 RTT(Round-Trip Time)를 측정함으로써 계층, 거리별 링크간의 LRD(Long-Range Dependence) 와 노드 큐의 특성, 자기유사성 정도를 구하고 측정된 데이터의 확률 분포를 통해 실제 트래픽의 특성에 대해 분석하였다

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Size Distribution and Temperature Dependence of Magnetic Anisotropy Constant in Ferrite Nanoparticles

  • Yoon, Sunghyun
    • Proceedings of the Korean Magnestics Society Conference
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    • 2012.11a
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    • pp.104-105
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    • 2012
  • The temperature dependence of the effective magnetic anisotropy constant K(T) of ferrite nanoparticles is obtained based on the measurements of SQUID magnetometry. For this end, a very simple but intuitive and direct method for determining the temperature dependence of anisotropy constant K(T) in nanoparticles is introduced in this study. The anisotropy constant at a given temperature is determined by associating the particle size distribution f(r) with the anisotropy energy barrier distribution $f_A(T)$. In order to estimate the particle size distribution f(r), the first quadrant part of the hysteresis loop is fitted to the classical Langevin function weight-averaged with the log?normal distribution, slightly modified from the original Chantrell's distribution function. In order to get an anisotropy energy barrier distribution $f_A(T)$, the temperature dependence of magnetization decay $M_{TD}$ of the sample is measured. For this measurement, the sample is cooled from room temperature to 5 K in a magnetic field of 100 G. Then the applied field is turned off and the remanent magnetization is measured on stepwise increasing the temperature. And the energy barrier distribution $f_A(T)$ is obtained by differentiating the magnetization decay curve at any temperature. It decreases with increasing temperature and finally vanishes when all the particles in the sample are unblocked. As a next step, a relation between r and $T_B$ is determined from the particle size distribution f(r) and the anisotropy energy barrier distribution $f_A(T)$. Under the simple assumption that the superparamagnetic fraction of cumulative area in particle size distribution at a temperature is equal to the fraction of anisotropy energy barrier overcome at that temperature in the anisotropy energy barrier distribution, we can get a relation between r and $T_B$, from which the temperature dependence of the magnetic anisotropy constant was determined, as is represented in the inset of Fig. 1. Substituting the values of r and $T_B$ into the $N{\acute{e}}el$-Arrhenius equation with the attempt time fixed to $10^{-9}s$ and measuring time being 100 s which is suitable for conventional magnetic measurement, the anisotropy constant K(T) is estimated as a function of temperature (Fig. 1). As an example, the resultant effective magnetic anisotropy constant K(T) of manganese ferrite decreases with increasing temperature from $8.5{\times}10^4J/m^3$ at 5 K to $0.35{\times}10^4J/m^3$ at 125 K. The reported value for K in the literatures is $0.25{\times}10^4J/m^3$. The anisotropy constant at low temperature region is far more than one order of magnitude larger than that at 125 K, indicative of the effects of inter?particle interaction, which is more pronounced for smaller particles.

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Antinarcotic Effect of Panax ginseng

  • Hack Seang Kim;Ki
    • Proceedings of the Ginseng society Conference
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    • 1990.06a
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    • pp.36-44
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    • 1990
  • The analgesic effect of morphine was antagonized and the development of tolerance was suppressed by the modification of the neurologic function in the animals treated with ginseng saponins. The activation of the spinal descending inhibitory systems as well as the supraspinal structures by the administration of morphine was inhibited in the animals treated with ginseng saponins intracerebrally or intrathecally The development of morphine tolerance and dependence, and the abrupt expression of naloxone induced abstinence syndrome were also inhibited by ginsenoside Kbl , Rba, Rgl and Re. These results suggest that ginsenoside Kbl, Rba, Rgl and Re are the bioactive components of panax ginseng on the inhibition of the development of morphine tolerance and dependence, and the inhibition of abrupt abstinence syndrome. In addition, further research on the minor components of Panax ginseng should be investigated. A single or daily treatment with ginseng saponins did not induce any appreciable changes in the brain level of monoamines at the various time intervals and at the various day intervals, respectively The inhibitory or facilitated effects of ginseng saponins on electrically evoked contractions in guinea pig ileum (U-receptor) and mouse was definers (5·receptor) were not mediated through opioid receptors. The antagonism of a x receptor agonist, U-, iO.488H was also not mediated through opioid receptors in the animals treated with ginseng saponins, bolt mediated through serotonergic mechanisms. Ginseng saponins inhibited morphine S-dehydrogenase that catalyzed the production of morphine from morphine, and increased hepatic glutathione contents for the detoxification of morphine. This result suggests that the dual action of the above plays an important role in the inhibition of the development of morphine tolerance and dependence.

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