• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.749-753
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• 1996

This paper presents a new method for first and second order eigen-sensitivity analysis of system matrix in augmented form. Eigen-sensitivity analysis provides invaluable informations in power system planning and operation. However, conventional eigen-sensitivity analysis methods, which need all the eigenvalues and eigenvectors, can not be applicable to large scale power systems due to large computer memory and computing time required. In the proposed method, all sensitivity computations for a mode are carried out using the augmented system matrix and its own eigenvalue and right & left eigenvectors. In other words sensitivity analysis for a mode does not need informations on the other eigenvalues and eigenvectors and sparsity technique can be fully utilized. Thus compuations can be done very efficiently with moderate computer memory and computing time even for large power systems. The proposed algorithm is tested for one machine infinite bus system.

• 한국자동차공학회논문집
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• 제8권2호
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• pp.129-137
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• 2000

In the prototype stage of a car developing program, the efficiency of trouble shooting is an important factor to be considered. Structural modifications by the design sensitivity analysis are applied to a steering wheel system for improving the idle vibration of the prototype passenger car. For the design sensitivity analysis, the experimental modal analysis for the steering system attached to a body-in-white is fulfilled and the modal parameters extracted from the experimental data are used to predict the effect of structural modification, The design sensitivity results rank the locations to be reinforced in terms of frequency variation. The modification of steering system according to the sensitivity analysis results shifted the resonant frequency of the system effectively. In addition, the idle test of the car after the structural modifications f steering system shows that the proposed method can reduce vibration of the steering wheel efficiently.

• 대한기계학회논문집A
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• 제20권12호
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• pp.3782-3791
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• 1996

A great deal of effert has been invested in upgrading the performance and the efficiency of mechanical structures. Using experimental modal analysis(EMA) or finite element analysis(FEA) data of mechanical structures, this performance and efficiency can be effectively evaluated. In order to analyze complex structures such as automobiles and aircraft, for the sake of computing efficiency, the dynamic substructuring techniques that allow to predict the dynamic behavior of a structure based on that of the composing structures, are widely used. By llinking a modal model obtained from EMA and an analytical model obtained from FEA, the best conditioned structures can be desinged. In this paper, a new algorithm for structural dynamic modification-SRFSM (substructure response function sensitivity method) is proposed by linking frequency responce function synthesis and response function sensitivity. A mehtod to obtain response function sensitivity using direct derivative of mechanical impedance, is also used.

• Structural Engineering and Mechanics
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• 제60권6호
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• pp.1093-1117
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• 2016

Global sensitivity analysis (GSA) has been widely used to investigate the sensitivity of the model output with respect to its input parameters. In this paper a new single-solution search optimization algorithm is developed based on the GSA, and applied to the size optimization of truss structures. In this method the search space of the optimization is determined using the sensitivity indicator of variables. Unlike the common meta-heuristic algorithms, where all the variables are simultaneously changed in the optimization process, in this approach the sensitive variables of solution are iteratively changed more rapidly than the less sensitive ones in the search space. Comparisons of the present results with those of some previous population-based meta-heuristic algorithms demonstrate its capability, especially for decreasing the number of fitness functions evaluations, in solving the presented benchmark problems.

• 한국보육지원학회지
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• 제14권6호
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• pp.1-18
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• 2018

Objective: The purpose of this study was to investigate relationships among child care teachers' role conflict, organizational commitment and teacher's sensitivity. It also aimed to test the mediating effect of organizational commitment on the pathway from child care teachers' role conflict on teacher's sensitivity. Methods: A self-report survey was conducted on 301 child care teachers in Chungbuk. Descriptive, means, standard deviations, correlations using SPSS 18.0, and Structural Equation Modeling using AMOS 18.0 were all conducted in order to analyze the collected data. Results: The results indicated that child care teachers' role conflict and organizational commitment had significant direct effects on teacher's sensitivity. This study also confirmed the significant mediating role of organizational commitment on the pathway from child care teachers' role conflict to sensitivity. Conclusion/Implications: The significance of role conflict and organizational commitment suggests that the integration of individuals with less conflict and more dedication will contribute more qualitative child care services by improving sensitive interactions with young children.

• 센서학회지
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• 제31권1호
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• pp.1-5
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• 2022

In this paper, the photocurrent characteristics of gate/body-tied (GBT) metal-oxide semiconductor field-effect transistor (MOSFET)-type photodetector with high sensitivity in the 408 nm - 941 nm range are presented. High sensitivity is important for photodetectors, which are used in several scientific and industrial applications. Owing to its inherent amplifying characteristics, the GBT MOSFET-type photodetector exhibits high sensitivity. The presented GBT MOSFET-type photodetector was designed and fabricated via a standard 0.18 ㎛ complementary metal-oxide-semiconductor (CMOS) process, and its characteristics were analyzed. The photodetector was analyzed with respect to its width to length (W/L) ratio, bias voltage, and incident-light wavelength. It was confirmed experimentally that the presented GBT MOSFET-type photodetector has over 100 times higher sensitivity than a PN-junction photodiode with the same area in the 408 nm - 941 nm range.

• 센서학회지
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• 제31권3호
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• pp.145-150
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• 2022

The importance of flexible polymer-based pressure sensors is growing in fields like healthcare monitoring, tactile recognition, gesture recognition, human-machine interface, and robot skin. In particular, health monitoring and tactile devices require high sensor sensitivity. Researchers have worked on sensor material and structure to achieve high sensitivity. A simple and effective method has been to employ three-dimensional pressure sensors. Three-dimensional (3D) structures dramatically increase sensor sensitivity by achieving larger local deformations for the same pressure. In this paper, the performance, manufacturing method, material, and structure of high-sensitivity flexible pressure sensors based on 3D structures, are reviewed.

• 대한수학회보
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• 제61권1호
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• pp.247-262
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• 2024

In this paper we introduce and study the notions of topological sensitivity and its stronger forms on semiflows and on product semiflows. We give a relationship between multi-topological sensitivity and thick topological sensitivity on semiflows. We prove that for a Urysohn space X, a syndetically transitive semiflow (T, X, 𝜋) having a point of proper compact orbit is syndetic topologically sensitive. Moreover, it is proved that for a T₃ space X, a transitive, nonminimal semiflow (T, X, 𝜋) having a dense set of almost periodic points is syndetic topologically sensitive. Also, wherever necessary examples/counterexamples are given.

• Journal of Nutrition and Health
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• 제30권9호
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• pp.1035-1044
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• 1997

There is substantial evidence that insulin sensitivity can be enhanced through appropriate dietary management . In this study, insulin sensitivity was evaluated using and insulin suppression test. Male Sprague-Dawley rats, were caused to be in a diabetic condition by the injection of streptozotocin, and divided into four groups. They were fed one of the following diets for 2 weeks : (group 1) a high-carbohydrate(CHO) low-fat low-fiber diet, (group 2) a high CHO low-fat and high-fiber diet, (group 3) a low-CHO high-fat and low-fiber diet, and (group 4) a low-CHO low-fat diet groups (as comparison between group 1 and group 2 shows). In the low-CHO high-fat diet groups, dietary fiber tended to decrease plasma glucose levels at the end of the experiment, but not significantly (as comparison between group 3 and group 4 shows). The average steady state plasma glucose level in rats on the group 3 diet was the highest among all four groups(p<0.05), indicating the poorest insulin sensitivity . However, high fiber increased insulin sensitivity in rats on the low-CHO high-fat diets(as shows by a comparison between group 3 and group 4). On the other hand , the high-CHO low-fat enhanced insulin sensitivity in rats on the low fiber diet(group 1 and group 3). The degree of enhancement of insulin sensitivity depends on the combination of CHO, fat , and fiber in the diet. In conclusion, this study demonstrates that a low-CHO high-fat low -fiber diet may be deleterious to diabetic rats. In view of insulin sensitivity enhancement , dietary fiber level is irrelevant, as long as the diet has a high-CHO and low-fat level.

• 성인간호학회지
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• 제20권6호
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• pp.950-959
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• 2008

Purpose: The present study was conducted in order to examine claustrophobia, noise sensitivity and vital signs according to anxiety sensitivity level in patients who have Magnet Resonance Imaging(MRI). Methods: With 100 outpatients, we measured anxiety sensitivity, claustrophobia, noise sensitivity and vital sign before and after MRI. Measuring tools were ASI, CLQ-M, and NSI. Data were collected from February to March, 2008. Results: The ASI score was higher in women than in men(p < .05), and no statistically significant difference was observed according to age, region of scanning, experience in MRI, and the use of contrast agent. Both men and women patients showed the same ASI score and decrease in CLQ M and NSI between before and after MRI. In women, ASI, CLQ M and NSI were in positive correlation with one another(p < .001), and in men, there was no correlation between ASI and CLQ M, and positive correlation was observed with NSI(p < .05). In comparison according to ASI level, blood pressure and pulse rate were not different in men and women. CLQ M was not different in men, but was different in women(p < .001). NSI was different in both men and women(men p < .05; women p < .001). Conclusion: MRI may cause claustrophobia in patients with high anxiety sensitivity, and noise appears to aggravate anxiety. In particular, claustrophobia was more serious in women than in men. Therefore, it is necessary to develop nursing interventions to reduce anxiety sensitivity particularly for female patients, and to make plans to educate and lower noise before MRI in order to reduce claustrophobia.