• Title/Summary/Keyword: sensitivity term

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Sensitivity analysis of time-dependent behaviors of PSC flexural members (프리스트레스트 훰 부재의 시간 종속적 거동에 관한 민감도 해석)

  • 김민주;김동기;김택중;이용학
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.05a
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    • pp.119-124
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    • 2001
  • A general procedure to implement the sensitivity analysis of PSC flexural members is proposed based on the analytical calculation of the gradients of stresses and strains with respect to the 21 design variables in a closed format. The formulation covers the long term losses including concrete creep, shrinkage, and PS steel relaxation as well as load effects. The derived formulation is applied to the rectangular section PSC beam with prestressing and nonprestressing steels for the sensitivity analysis. The analytically calculated sensitivity results are compared with those numerically calculated.

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Dual Doppler Wind Retrieval Using a Three-dimensional Variational Method (3차원 변분법을 사용한 이중 도플러 바람장 분석)

  • Lee, SeonYong;Choi, Young-Jean;Chan, Dong-Eon
    • Atmosphere
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    • v.17 no.1
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    • pp.69-86
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    • 2007
  • The characteristics of the dual-Doppler wind retrieval method based on a three dimensional variational (3DVAR) conception were investigated from the following four points of view; the sensitivity of the number of iteration, the effect of the weak constraint term, the effect of the smoothness term, and the sensitivity of the error mixing ratio of the radial velocities. In the experiment, the radial velocities relative to the Gosan and Jindo radar sites of the Korea Meteorological Administration (KMA) were calculated from the forecasting of the WRF (Weather Research and Forecast; Skamarock, 2004) model at 1330 UTC 30 June 2006, which is the one and half hour forecast from the initial time, 1200 UTC on that day. The results showed that the retrieval performance of the horizontal wind field was robust, but that of the vertical wind was sensitive to the external conditions, such as iteration number and the on/off of the weak constraint term. The sensitivity of error mixing ratio was so large that even the horizontal wind retrieval efficiency was reduced a lot. But the sensitivity of the smooth term was not so large. When we applied this method to the real mesoscale convective system (MCS) between the Gosan and Jindo radar pair at 1430 UTC 30 June 2006, the wind structure of the convective cells in the MCS was consistently retrieved relative to the reflectivity factor structure. By comparing the vertical wind structure of this case with that of 10 minutes after, 1440 UTC 30 June 2006, we got the physical consistency of our method.

Influence of Stain on the High Frequency Impedance of Highly Magnetostrictive Films (고자왜막의 고주파임피던스에 미치는 스트레인의 영향)

  • ;M. Inoue;K. I, Arai
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.1
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    • pp.47-51
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    • 2000
  • To make a practical application of a micro-strain sensors with ultrahigh sensitivity, a strain on electrical properties of micro-patterned amorphous (Fe\ulcornerco\ulcorner)\ulcornerSi\ulcornerB\ulcorner films had influenced on the impedance over frequency range from 1 MHz to 1 GHz. Reflecting excellent magnetomachanical couping properties of films, high frequency impedance was subject to change sensitively by a strain : a change in impe-dance of 39% was observed at 200 MHz applied a strain of 224$\times$10\ulcorner. To determine a optimum shape of micro-patterned films, film impedance was analyzed by virtue of its constitutive components of resis-tance and reactance. Result was shown that reduction of the resistance term(hence increase of resultant reactance term) of impedance is more effective for enhancing the strain sensitivity of films at relatively low frequency range.

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Short-Term Load Forecasting Using Neural Networks and the Sensitivity of Temperatures in the Summer Season (신경회로망과 하절기 온도 민감도를 이용한 단기 전력 수요 예측)

  • Ha Seong-Kwan;Kim Hongrae;Song Kyung-Bin
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.54 no.6
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    • pp.259-266
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    • 2005
  • Short-term load forecasting algorithm using neural networks and the sensitivity of temperatures in the summer season is proposed. In recent 10 years, many researchers have focused on artificial neural network approach for the load forecasting. In order to improve the accuracy of the load forecasting, input parameters of neural networks are investigated for three training cases of previous 7-days, 14-days, and 30-days. As the result of the investigation, the training case of previous 7-days is selected in the proposed algorithm. Test results show that the proposed algorithm improves the accuracy of the load forecasting.

The Short-Term Effects of Soft Pellets on Lipogenesis and Insulin Sensitivity in Rats

  • Bae, Cho-Rong;Hasegawa, Kazuya;Akieda-Asai, Sayaka;Kawasaki, Yurie;Cha, Youn-Soo;Date, Yukari
    • Preventive Nutrition and Food Science
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    • v.19 no.3
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    • pp.164-169
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    • 2014
  • The purpose of the present study was to investigate the short-term effects of a 12-day, soft pellet (SP) diet with a 3-h restricted feeding schedule on caloric intake, body weight, lipid metabolism, and insulin sensitivity. Glucose and insulin levels were measured pre-, mid-, and post-feeding. The SP rats exhibited postprandial hyperglycemia compared to rats fed control pellets (CP). The insulin response of SP rats during a meal was significantly higher than that of CP rats. There were no significant differences in the hepatic triacylglycerol contents and lipogenesis gene mRNA levels of SP and CP rats. However, the hepatocytes of SP rats were slightly hypertrophic. In addition, histological analysis revealed that the pancreases of SP rats had more islet areas than those of CP rats. This study demonstrated that feeding an SP-only diet for 12 days induces glucose intolerance, suggesting that the consumption of absorbable food, like a soft diet, may trigger glucose metabolism insufficiency and lead to life-threatening diseases.

Short-term Toxicity Assay Based on Daphnid Feeding on the Microalga Scenedesmus subspicatus

  • Lee Sang-Ill;Park Jong-Ho;Lee Won-Ho;Yeon Ik-Jun;Lee Byoung-Chan;Cho Kyu-Seok;Choi Hyun-Ill
    • Fisheries and Aquatic Sciences
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    • v.9 no.1
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    • pp.38-43
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    • 2006
  • We developed and evaluated a method of short-term acute toxicity testing based on the feeding behavior of Ceriodaphnia dubia. In prior toxicity tests, neonates of C. dubia were hatched and cultivated with the addition of yeast only for the preparation of the transparent daphnid's gut. Scenedesmus subspicatus was supplied as food after 1 to 6 h of exposure to toxicants. The effects of 1-h and 6-h exposure time on test sensitivity did not significantly differ. A comparison of the short-term l-h acute toxicity test developed in this study to the standard 48-h acute toxicity test using heavy metals, cyanide, and pentachlorophenol indicated that the 1-h test provided an acceptable sensitivity level in toxicity testing of C. dubia..

Influence of Ethical Sensitivity and Person-environment Fit on Person-centered Care of Nurses in Long-term Care Hospitals (요양병원 간호사의 윤리적민감성과 개인-환경적합성이 인간중심돌봄에 미치는 영향)

  • Lee, Hye Ran;Yang, Nam Young
    • Journal of Korean Academic Society of Home Health Care Nursing
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    • v.29 no.2
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    • pp.175-182
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    • 2022
  • Purpose: The study examined the effects of ethical sensitivity and person-environment fit on person-centered care of nurses in long-term care hospitals. Methods: The participants were 111 nurses. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient, and multiple regression analysis with the SPSS program. Results: The mean of person-centered care was 2.95±0.62 out of 5. There were significant differences in person-centered care in terms of age, shift pattern, total clinical career, and educational experience of person-centered care. Person-centered care and ethical sensitivity, person-centered care and person-environment fit showed a positive correlation. Factors affecting the person-centered care were the age (20-29), shift pattern (three shift), person-environment fit. The explanatory power was 42%. Conclusion: These results can be used to increase the person-environment fit and adopt a differented approach based on age and shift pattern in order to enhance person-centered care. Therefore, it is necessary to develop and apply an person-centered care program for nurses in long-term care hospitals.

Effect of mitigation strategies in the severe accident uncertainty analysis of the OPR1000 short-term station blackout accident

  • Wonjun Choi;Kwang-Il Ahn;Sung Joong Kim
    • Nuclear Engineering and Technology
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    • v.54 no.12
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    • pp.4534-4550
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    • 2022
  • Integrated severe accident codes should be capable of simulating not only specific physical phenomena but also entire plant behaviors, and in a sufficiently fast time. However, significant uncertainty may exist owing to the numerous parametric models and interactions among the various phenomena. The primary objectives of this study are to present best-practice uncertainty and sensitivity analysis results regarding the evolutions of severe accidents (SAs) and fission product source terms and to determine the effects of mitigation measures on them, as expected during a short-term station blackout (STSBO) of a reference pressurized water reactor (optimized power reactor (OPR)1000). Three reference scenarios related to the STSBO accident are considered: one base and two mitigation scenarios, and the impacts of dedicated severe accident mitigation (SAM) actions on the results of interest are analyzed (such as flammable gas generation). The uncertainties are quantified based on a random set of Monte Carlo samples per case scenario. The relative importance values of the uncertain input parameters to the results of interest are quantitatively evaluated through a relevant sensitivity/importance analysis.

Effect of Short-Term Pharmacotherapy on Anxiety Sensitivity, Quality of Life and Functional Disability in Panic Disorder Patients (공황장애에서 단기약물치료가 불안민감도와 삶의 질 및 기능장애에 미치는 영향)

  • Oh, Yun-Hye;Choi, Kwan-Woo;Kim, Bora;Heo, Jung-Yoon;Yu, Bum-Hee
    • Anxiety and mood
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    • v.9 no.1
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    • pp.25-30
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    • 2013
  • Objective : Panic disorder is a chroni, debilitating illness, and has been known to be affected by high anxiety sensitivity and a poor quality of life. We examined if 12 weeks of pharmacotherapy with escitalopram could affect anxiety sensitivity, quality of life, and general disability in patients with panic disorder. Method : We enrolled 27 patients who met the DSM-IV-TR criteria for panic disorder, with or without agoraphobia, and completed 12 weeks of escitalopram treatment. We enrolled 29 normal control subjects who were matched for age and sex compared with the panic patients. All subjects were assessed using the Hamilton Rating Scale for depression (HAM-D), Hamilton Rating Scale for Anxiety (HAM-A), Panic Disorder Severity Scale (PDSS), Anxiety Sensitivity Index-Revised (ASI-R), WHO quality of life assessment (WHO-QOL) and Sheehan Disability Scale (SDS) before and after 12 weeks of treatment. Result : Panic disorder patients had a higher Anxiety sensitivity, a poorer Quality of life, and significant disability than normal control subjects at baseline. After the treatment, Panic disorder patients showed significant improvement in the severity of panic symptoms in terms of the HAM-A p<0.001), HAM-D (p<0.001) in addition, the reached a remission state in terms of the PDSS score. They also showed significant improvement in the ASI-R (p<0.001), WHO-QOL (p<0.001) and SDS (p<0.001), but mean scores of the ASI-R, WHO-QOL and SDS in panic disorder patients were did not reach normal levels. Conclusion : This study suggests that 12 weeks of pharmacotherapy with escitalopram could improve anxiety sensitivity, quality of life, and disability in panic disorder patients, although their anxiety sensitivity, quality of life and disability were not yet normalized after short-term pharmacotherapy. Thus, long-term pharmacotherapy may be necessary for panic disorder patients in order to get an optimal clinical response in terms of anxiety sensitivity, quality of life, and general disability.

Salt Intake Behavior and Blood Pressure: the effect of taste sensitivity and preference (소금 섭취 행태와 혈압: 맛에 대한 민감도와 선호도의 영향)

  • Kim, Jin-Hee;Choi, Man-Kyu
    • Korean Journal of Human Ecology
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    • v.16 no.4
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    • pp.837-848
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    • 2007
  • The literature suggested that a small reduction in overall blood pressure can have a large effect on overall prevalence of hypertension, and therefore, the affect of taste preferences of the population on salt intake should be considered for long-term blood pressure intervention programs. The purpose of this study is to investigate the influence of salt taste preference and salt taste sensitivity on salt intake behavior as risk factors for high blood pressure. We collected information on blood pressure, diet and lifestyle behaviors, salt taste preference and salt taste sensitivity from 540 respondents from Suseo-dong, Seoul. Salt taste sensitivity was assessed by administering a 1% NaCl solution to the subject's tongue and measuring the perceived intensity on 10 level scale. Salt intake behavior was classified into 3 categories: frequency of high-sodium foods, practice of salt-reducing behavior and frequency of vegetable and fruit intake. Salt taste preference showed a significant relation to the subjects' blood pressure, i.e. subjects with a higher salt preference had higher blood pressure. Salt taste sensitivity did not show a significant relation to blood pressure. However, there was a positive correlation between salt taste preference and salt taste sensitivity. Among the 3 indicators used to measure salt intake behavior, the practice of salt-reducing behavior remained significantly correlated to blood pressure. Moreover, salt-reducing behavior and salt taste preference showed a significant correlation, i.e. people who do not like salty foods tend to practice more salt-reducing behavior, leading to reduced levels in blood pressure. In a population, a small reduction in overall blood pressure can have large effects in overall prevalence of hypertension, in contrast to clinical studies where achievement of an individual's normal blood pressure is emphasized. Therefore, taste preference of the population should be considered for long-term blood pressure intervention programs.