• Journal of the Korean Solar Energy Society
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• v.31 no.4
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• pp.136-141
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• 2011

The lightshelf system reduces intense illumination levels of indoor from direct sun light and reflect to lead diffused light into indoor deeply. This study aims to design acurved-lightshelf by a ray tracing method and evaluate the daylighting performance of window integrated with the curved-lightshelf by computer simulations. For this purpose, evaluation test model was designed for the experiments to validate the simulation model, and the curved-lightshelf was designed by the ray tracing method using Ecotect. After the office model was designed using 3D simulation, the average indoor illuminance, luminance and distribution of illuminance were evaluated by simulation which has a algorithm of Radiosity and Ray-Tracing method under four different cases(case1;no lightshelf, case2; Flat board, case3; tilted at $30^{\circ}$ angle, case4; the curved-lightshelf). As results, it turns out that case1 showed higher average illuminance and case4 was more uniformly distributed than case2 and case3, In addition average luminance of case1 was also lower. indicating that the curved-lightshelf would reduce the possibility of the glare, while maintaining the sufficient daylight level.

• Korea Real Estate Review
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• v.27 no.4
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• pp.63-76
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• 2017

The purpose of this study is to analyze the effect of the results of a nationwide academic evaluation of middle schools and high schools on apartment prices in Ulsan City by using a hedonic pricing model. The results of the middle school and high school achievement test, the College Scholastic Ability Test (CSAT) score for high school, the national united evaluation score, and the number of successful applicants to prestigious universities have a significant effect on the apartment price formation with a positive relationship. In addition, different kinds of academic evaluation score have asymmetric effects on apartment price determination. The results of the high school achievement evaluation are more important than the results of the middle school achievement evaluation in the apartment price determination. Among the achievement evaluation results, the ratio of the students with the higher education level is more important than the ratio of the students with the lower basic education level. Furthermore, the CSAT score for Natural Sciences is more important than the CSAT score for the Humanities course.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.3
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• pp.210-220
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• 2001

This paper aims at the evaluation on the characterization of CFRP laminate plates using falling weight impact tester. The experimentation was conducted on several laminates of different fiber and ply orientation. A system was built for the impact strength of CFRP laminates in consideration of stress wave propagation with using drop-weight impact tester as one of impact test. Absorbed energy of orthotropic composites with using T300 fiber, which are composed of the same fiber and stacking number is higher than that or quasi-isotropic specimen over impact energy 7J, but in case or using T700 fiber, much difference does not show. Also, absorbed energy of orthotropic composites with using T300 fiber, which are composed or stacking number and orientation became more than that of T700 fiber specimen; however great change doesn't show in case of quasi-isotropic specimens. It is found that influence was confirmed between impact energy and absorbed energy as the impact energy is increased with adding the falling weight.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.167-170
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• 2009

Fast cook-off test with rocket motors was performed and characteristics of the results were analyzed. The material of the motor case was carbon epoxy composite. The motor was loaded with HTPE propellants to improve the insensitive munitions characteristics. In the tests, sound pressure and heat flux sensors were used to determine the category of response according to the standard. The reaction response of all of the HTPE motors tested by fast cook-off was judged as Type V burning.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.163-166
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• 2009

Bullet and fragment impact test with rocket motors was performed and characteristics of the results were analyzed. The material of the motor case was carbon epoxy composite. The motor was loaded with HTPE propellants to improve the insensitive munitions characteristics. In the tests, sound pressure and heat flux sensors were used to determine the category of response according to the standard. The reaction response of all of the HTPE motors impacted by bullet and fragment was judged as Type V burning.

• Korean Journal of Bronchoesophagology
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• v.5 no.1
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• pp.55-61
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• 1999

The authors recently experienced a case of ectopic thyroid. A 15-year-old female patient visited to ENT department with the complaint of the submental neck mass. On physical examination, the mass was relatively firm, non tender and 3$\times$2cm in size. Oral cavity examination revealed 0.5$\times$0.5cm sized pink colored mass near the foramen cecum area. Suspecting ectopic thyroid, thyroid function test, thyroid scan, neck computed tomogram scan were performed. Thyroid scan revealed a functioning thyroid on the lingual and submental area without normal uptake in the anterior neck area. Thyroid (unction test was normal. Pre-contrast computed tomogram scan revealed an ectopic thyroid in the lingual and submental area. A review of literature concerning ectopic thyroid was discussed.

• KIEAE Journal
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• v.15 no.1
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• pp.77-82
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• 2015

The purpose of this study is to compare the thermal insulation performance of windows according to the formation of air layer and to evaluate its energy efficiency on a selected standard house. A thermal insulation test, KS F 2278 was used to measure U-values (Heat transmission coefficients) for the following three cases: the first case (Case 1) is a Low-E pair glass (Argon injected), the second case (Case 2) is a Low-E pair glass with the air cap attached on the glass surface, and the third case (Case 3) is a Low-E pair glass, on the frame of which the air cap is attached. The evaluation of the energy efficiency was conducted according to a building energy calculation method from ISO 13790, calculation of energy use for space heating and cooling, using the U-values obtained from the thermal insulation tests. As results of the tests, the U-values of Case 1, Case 2, and Case 3 were $1.668W/m^2{\cdot}K$, $1.568W/m^2{\cdot}K$, and $1.319W/m^2{\cdot}K$ respectively. The Case 2 had about 5.9% lower value than the Case 1, and the Case 3 had about 20.9% lower value than the Case 1. It seems that the thermal performance of the windows is attributed to an increase of the heat resistance and the thickness of air layer. An evaluation of the energy efficiency of the three cases on the selected standard house showed that the amount of heating energy demand per unit area was $7.776kWh/m^2{\cdot}yr$ for the Case $1,6.856kWh/m^2{\cdot}yr$ for the Case 2, and $4.856kWh/m^2{\cdot}yr$ for the Case 3. This study suggests that the formation of air layer (by using air cap) and its thickness should reduce the heat energy demand and thus improve the energy saving efficiency

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.18-27
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• 2020

This study compared and analyzed the results of proficiency testing between testers based on the international standard ISO/IEC 17043 proficiency testing requirements using ISO/IEC 25023 software quality characteristics evaluation. Application of the test was submitted to the KASTO as a software test in the electric test field defined by KOLAS. Among ISO/IEC 25023, the evaluation items for proficiency testing between testers were selected as functional completeness and time behavior. The comparison test between testers was carried out on May 28, 2019 at the accredited LG Electronics SW Laboratory in Seoul and attended by KOLAS assessors. The test evaluation method was measured once per tester with functional completeness, and measurement was repeated 10 times per tester according to time behavior. As a result, in the case of functional completeness, all 12 test steps were passed, and the satisfaction was evaluated. Time behavior was repeated 10 times, and the mean was 9.45 ± 0.01 seconds for testers 1 and 3 and 9.52 ± 0.0 seconds for tester 2, but there was no statistically significant difference. In conclusion, the proficiency of the testers was equal, and the reliability of the test results of the test institute was confirmed.

• Journal of Information Technology Applications and Management
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• v.27 no.6
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• pp.101-116
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• 2020

This study attempts to derive critical success factors and prioritize activities for implementing the automation of software test. Software testing proceeds in five steps of test plan, test case design, test scripting & test environment setup, test execution & evaluation, and test closure. From the literature, twenty influence factors in the five steps were identified. Focus Group Interviews with ten experts in software testing selected fourteen factors on the basis of importance and feasibility. Some factors were further divided to clarify their meanings and the number of influence factors finally became twenty one. A survey on the influence factors was conducted with 75 IT professionals. An importance-feasibility analysis was applied to the survey responses and classified the influence factors into four groups of essential factors, critical factors, low priority factors, and minimal factors. Essential factors include objectives for test automation, strategies for test automation, test automation training, test automation education, setting up test automation environment, setting up test environment, test automation tool selection. Critical factors include management's continued support, management's continued interest, role of automation engineers, and skills of automation engineers. This result suggests that a lot of efforts should be put into SW test plan for the successful SW test automation and SW automation should proceed in consideration with the priorities and resource consumption.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.147-153
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• 2020

Developments in aircraft require safety verification through flight testing for many hours with prototype design and production. The test evaluation step of performing flight tests was an important process that determines the success in the development of the system. In particular, safety development through flight tests in the armed flight test is important for the development of attack helicopters. In the development of attack helicopters, the evaluation period and cost related to the armed flight test are closely related to the required ammunition requirement. Therefore, this paper presents the amount of ammunition required for the military flight test between attack helicopter developments through an analysis of the AH-1 helicopter in a similar case and ADS-44-HDBK of military specification. The AH-1 can be used to calculate the ammunition demand by considering the exclusion of redundant firing tests and configuration differences. In the case of the machine gun-equipped configuration, approximately 10,500R was required, and approximately 324R was required in the case of a rocket-mounted configuration. In addition, if the armed integrated bench is used properly, it is expected to promote efficiently the flight test in the armed flight by identifying the possible risk factors with armed flight tests and excluding them.