• Journal of radiological science and technology
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• v.33 no.1
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• pp.31-36
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• 2010

Low energy high resolution (LEHR) collimator is the most widely used collimator in SPECT imaging. LEHR has an advantage in terms of image resolution but has a difficulty in acquiring high sensitivity due to the narrow hole size and long septa height. Throughput in SPECT can be improved by increasing counts per second with the use of high sensitivity collimators. The purpose of this study is to develop a system model in iterative image reconstruction to recover the resolution degradation caused by high sensitivity collimators with bigger hole size. We used fan-beam model instead of parallel-beam model for calculation of detection probabilities to accurately model the high sensitivity collimator with wider holes. In addition the weight factors were calculated and applied onto the probabilities as a function of incident angle of incoming photons and distance from source to the collimator surface. The proposed system model resulted in the equivalent performance with the same counts (i.e. in shortened acquisition time) and improved image quality in the same acquisition time. The proposed method can be effectively applied for resolution improvement of pixel collimator of next generation solid state detectors.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.9
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• pp.55-66
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• 2018

This study aims to propose color affective model of indoor space by evaluating subjects' physiological responses according to the types of behavioral and affective system. 99 subjects(44 females, 55 males) in their 20s, who had no disorders in visual perception, participated in the experiment. To categorize the subjects based on behavioral and affective system, BAS/BIS scale and Affective scale were used. Color stimuli were composed of five basic colors and three tones: vivid, pale and dull tone of R, Y, G, B, P. For physiological experiment, right and left prefrontal alpha activity was measured to analyze prefrontal EEG asymmetry. Participants were exposed to fifteen color stimuli for 20 seconds each other under the positive and negative emotional condition in a research room with the natural light blocked. The results and conclusion of this study are as follows. Along with factors of behavioral and affective system, cluster analysis was carried out and four types were classified. Type A had high BAS sensitivity, especially high 'drive' trait, and showed high levels of 'anxiety' and 'anger'. Type B had low BAS sensitivity, especially low 'fun seeking' and low 'drive' trait, and showed low levels of 'anxiety' as well as low levels of 'happiness'. Type C had low BIS sensitivity and showed high levels of 'happiness' and low levels of 'sadness'. Type D had high BIS sensitivity and showed high levels of 'lethargy' and 'sadness'. As a result of EEG signal analysis of color stimuli, Type B, Type C, and Type D showed significant differences in prefrontal alpha asymmetry under the negative emotional stimuli. Type B showed more left prefrontal activation in the spaces with pale R and dull G. Type C showed more left prefrontal activation in the spaces with vivid Y and B, pale R, and dull R, G, P. Type D showed more left prefrontal activation in the spaces with vivid Y and P, pale R, Y, P, and dull R, Y, G, B, P. The group of high BAS sensitivity was not influenced by color stimuli under the emotional conditions, whereas the group of high BIS sensitivity was affected by color stimuli under the negative emotional conditions. They showed left prefrontal activation when they were exposed the spaces with vivid, pale, dull tones of Y and P wall.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05a
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• pp.80-84
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• 2004

The goal of the project is to study and describe a new stressed state of High Temperature Superconducting (High-Tc) YBCO Films, to create of SQUIDs on the bases of these Films with maximal sensitivity. The problems of the project are: 1. The experimental studying of the stressed films growing by laser ablation method. 2. The studying of stressed film properties. 3. The making of the dc-SQUIDs with maximal sensitivity on the bases of the stressed YBCO films.

• The Journal of the Korea Contents Association
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• v.13 no.8
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• pp.191-200
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• 2013

This study set out to explore the human rights sensitivity of undergraduates who were in the social welfare classes with regards to socio-demographic factors, education experiences in human rights. 251 students' data were collected and analyzed with frequency, ANOVA. Analysis revealed that students' human rights sensitivity level was 2.70(moderate) and the respondents showed high level of sensitivity in work rights of emigration workers and education rights of handicapped children. Among demographic variables, human rights sensitivity was significantly different from major and experiences of attending a social welfare ethics. The students who majored social welfare and who had attended a social welfare ethics showed high human rights sensitivity. There were differences in human rights sensitivity level according to each episode. These findings highlight that in the education of social worker as a human rights professionals it would be necessary to respect students' rights in the classes and to provide student customized human rights education. It was suggested that learning human rights dilemma cases and self reflection processes in classes would be necessary to effective human rights education.

• Journal of the Korean Society of Earth Science Education
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• v.6 no.2
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• pp.145-151
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• 2013

The aim of this research is clarify the relationship between concept understanding degree about the environment and environmental sensitivity and heighten understanding of environmental education target to pre-service elementary teacher. The subjects of this study are science education intensive course 65 students of B educational university. Concept understanding degree about the environment was separately investigated by 'the definition of environmental education', 'Write The positive concept of the natural environment education and briefly describe.''The negative concept of the natural environment education and briefly describe'. Next clarify the relationship between concept understanding degree about the environment and environmental sensitivity target to pre-service elementary teacher. Based on these results, propose an alternative to cultivate pre-service elementary teacher's knowledge about environmental education. Degree of understanding of the concept environmental education research results are as follows. First, Cognition degree about definition of environmental education of pre-service elementary teacher is correctly recognized generally. Second, They do not think deeply about natural environment when it comes to the positive concept of the natural environment of pre-service elementary teacher. Third, They have only a little interest in natural environment when it comes to the negative concept of the natural environment of pre-service elementary teacher. Correlation research results of degree of understanding of the concept of environmental and environmental sensitivity are as follows. High understanding degree of environmental education is high environmental sensitivity. Heighten environmental sensitivity of pre-service elementary teacher will be sustainable environmental education so education is necessary for environmental Sensitivity training.

• Transactions on Electrical and Electronic Materials
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• v.18 no.2
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• pp.78-88
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• 2017

Cantilever beam MEMS piezoelectric accelerometers are the simplest and most widely used accelerometer structure. This paper discusses the design of a piezoelectric accelerometer exclusively for SHM applications. While such accelerometers need to operate at a lower frequency range, they also need to possess high sensitivity and low noise floor. The availability of a simple model for deflection, charge, and voltage sensitivities will make the accelerometer design procedure less cumbersome. However, a review of the open literature suggests that such a model has not yet been proposed. In addition, previous works either depended on FEM analysis or only reported on the fabrication and characterization of piezoelectric accelerometers. Hence, this paper presents, for the first time, a simple analytical model developed for the deflection, induced voltage, and charge sensitivity of a cantilever beam piezoelectric accelerometer.The model is then verified using FEM analysis for a range of different cases. Further, the model was validated by comparing the induced voltages of an accelerometer estimated using this model with experimental voltages measured in the accelerometer after fabrication. Subsequently, the design of an accelerometer is demonstrated for SHM applications using the analytical model developed in this work. The designed accelerometer has 60 mV/g voltage sensitivity and 2.4 pC/g charge sensitivity, which are relatively high values compared to those of the piezoresistive and capacitive accelerometers for SHM applications reported earlier.

• Korean Journal of Veterinary Research
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• v.50 no.1
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• pp.43-48
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• 2010

Animal disease surveillance system, defined as the continuous investigation of a given population to detect the occurrence of disease or infection for control purposes, has been key roles to assess the health status of an animal population and, more recently, in international trade of animal and animal products with regard to risk assessment. Especially, for a system aiming to determine whether or not a disease is present in a population sensitivity of the system should be maintained high enough not to miss an infected animal. Therefore, when planning the implementation of surveillance system a number of factors that affecting surveillance sensitivity should be taken into account. Of these parameters sample size is of important, and different approaches are used to calculate sample size, usually depending on the objective of surveillance systems. The purpose of this study was to evaluate the sensitivity of the current national serological surveillance programs for four selected bovine diseases assuming a specified sampling plan, to examine factors affecting the probability of detection, and to provide sample sizes required for achieving surveillance goal of detecting at least an infection in a given population. Our results showed that, for example, detecting low level of prevalence (0.2% for bovine tuberculosis) requires selection of all animals per typical Korean cattle farm (n = 17), and thus risk-based target surveillance for high risk groups can be an alternative strategy to increase sensitivity while not increasing overall sampling efforts. The minimum sample size required for detecting at least one positive animal was sharply increased as the disease prevalence is low. More importantly, high reliability of prevalence estimation was expected with increased sampling fraction even when zero-infected animal was identified. The effect of sample size is also discussed in terms of the maximum prevalence when zero-infected animals were identified and on the probability of failure to detect an infection. We suggest that for many serological surveillance systems, diagnostic performance of the testing method, sample size, prevalence, population size, and statistical confidence need to be considered to correctly interpret results of the system.

• Biomolecules & Therapeutics
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• v.9 no.4
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• pp.277-281
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• 2001

Chromium is an essential nutrient and participates in glucose and lipid metabolism in human beings and animals. The present study was conducted to assess the effects of chromium picolinate (Cr-pic) on glucose tolerance and insulin sensitivity in type I and ll diabetic rats. The experimental groups were type I diabetic (streptozotocin-induced: 40 mg/kg, i.p.) and type II diabetic (Goto-Kakizaki rats) models. Each group was subdivided into control. low-dose and high-dose of Cr-pic treated groups. The Cr-pic was orally administered with Cr-pic (100 mg/kg for low dose group and 200 mg/kg for high dose group) for 4 weeks. And then we performed intraperitoneal glucose tolerance test (IPGTT) and insulin sensitivity test (ITT). The glucose tolerance test was carried out by inection of glucose (2 g/kg, i.p.). The peripheral insulin sensitivity test was con- ducted by injection of insulin (5 units/kg, s.c.) and glucose. We performed determining of blood glucose concentration at 0, 10, 30, 60, 90, and 120 min using automated glucose analyzer. The plasma insulin concentration was determined by rat insulin EIA kit. Administration of Cr-pic improved weight gain in all group s with higher significant in the low-dose group. There was no significance between the control and the Cr-pic treated groups in the area under the blood glucose curve and serum insulin concentration plots of IPGTT and peripheral ITT in type I diabetic rats. But Cr-pic treated groups showed significantly lower levels of the area under the blood glucose currie during IPGTT and ITT and the high-dose group showed less effects compared with the low-dose group in the type II diabetic rats. The plasma insulin concentration of both diabetic groups was not influenced by Cr-pic supplementation. We can conclude that chromium picolinate may improve the endogenous and exogenous insulin action and peripheral insulin sensitivity in type II diabetic rats.

• Journal of Advanced Navigation Technology
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• v.23 no.5
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• pp.415-423
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• 2019

In this paper, a design method for a high-sensitivity microstrip patch sensor antenna (MPSA) loaded with a bent-slot was studied for the permittivity measurement. The bent-slot similar to a single-ring complementary split ring resonator was added along a radiating edge of the patch in order to enhance the sensitivity to the permittivity. The sensitivity of the proposed MPSA was compared with that of a conventional rectangular MPSA and a thin rectangular-slotted MPSA. Three MPSAs were designed and fabricated on a 0.76-mm-thick RF-35 substrate so that the input reflection coefficient would resonate at 2.5 GHz in the absence of the superstrate under test. When five different Taconic substrates with a relative permittivity ranging from 2.17 to 10.2 were used as the superstrate under test, experiment results show that the sensitivity of the proposed MPSA, which is measured by the shift in the resonant frequency of the input reflection coefficient, is 4.1 to 6.1 times higher than that of the conventional MPSA.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.11
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• pp.79-85
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• 1995

In this paper, an epi layer and a device structure for InP/InGaAs p-i-n/HBT OEIC is designed for a receiving frontend of high speed optical communications. A 3 stage transimpedance circuit using the p-i-n/HBT device is also designed by SPICE simulations for a high sensitivity including ISI noises at a given bit rate. Our simulations show that the Personick's assumption which is not commonly satisfied have estimated a photoreceiver sensitivity too high, so thus we have to also consider ISI noises in OCIC receiver designs.