• Journal of the Korean Society of Safety
• /
• v.33 no.4
• /
• pp.15-20
• /
• 2018

In this study, we have performed the Cone Calorimeter test and Smoke density test in accordance with ISO 5660-1 and ASTM E662 respectively to check the smoke production characteristics of rubber flooring materials for railway vehicle. Early in the ASTM E662 test, more smoke was produced in the flame mode test than non-flame mode test, but later more smoke was produced in non-flame mode test. The correlation($R^2$) between TSR(Total Smoke Release) by ISO 5660-1 and Ds(Specific Optical Density) by ASTM E662 Flame mode was 0.782. The $R^2$ between TSR by ISO 5660-1 and Ds by ASTM E662 Non-flame was 0.930.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.25 no.4
• /
• pp.662-670
• /
• 2001

We evaluate the effectiveness and validity of J(sub)e, which comprehensively describes the effects of specimen geometry and loading type, in predicting the fatigue life of auto seat belt anchor panel. We first simplify the heat affected zone model to reduce the number of finite elements. We then establish finite element models reflecting the actual overload behavior of 3 types of seat belt anchor specimens. Using finite element models elaborately established, we obtain the effective crack driving parameter J(sub)e composed of its ductility-dependent modal components. It is confirmed that the J(sub)e concept successfully predicts the fatigue life of multi-spot welded panel structures represented by auto seat belt anchors here.

• Journal of Radiation Protection and Research
• /
• v.41 no.2
• /
• pp.179-183
• /
• 2016

Background: As an important detecting device, TLD is a widely used in the radiation monitoring. It is essential for us to study the property of detecting element. The aim of this study is to calculate the thermo-luminescence efficiency of TL elements. Materials and Methods: A batch of thermo-luminescence elements were irradiated by the filtered X-ray beams of average energies in the range 40-200 kVp, 662 keV $^{137}Cs$ gamma rays and then the amounts of lights were measured by the TL reader. The deposition energies in elements were calculated by theory formula and Monte Carlo simulation. The unit absorbed dose in elements by photons with different energies corresponding to the amounts of lights was calculated, which is called the thermo luminescent efficiency (${\eta}^{(E)}$). Because of the amounts of lights can be calculated by the absorbed dose in elements multiply ${\eta}^{(E)}$, the ${\eta}^{(E)}$ can be calculated by the experimental data (the amounts of lights) divided by absorbed dose. Results and Discussion: The deviation of simulation results compared with theoretical calculation results were less than 5%, so the absorbed dose in elements was calculated by simulation results in here. The change range of ${\eta}^{(E)}$ value, relative to 662 keV $^{137}Cs$ gamma rays, is about 30% in the energy range of 33 keV to 662 keV, is in accordance by the comparison with relevant foreign literatures. Conclusion: The ${\eta}^{(E)}$ values can be used for updating the amounts of lights that are got by the direct ratio assumed relations with deposition energy in TL elements, which can largely reduce the error of calculation results of the amounts of lights. These data can be used for the design of individual dosimeter which used TLD-2000 thermo-luminescence elements, also have a certain reference value for manufacturer to improve the energy-response performance of TL elements by formulation adjustment.

• 한국디지털정책학회:학술대회논문집
• /
• 2004.05a
• /
• pp.651-662
• /
• 2004

인터넷의 성장과 더불어 e-learning 을 통한 교육의 기회가 증가하고 있다. 본 연구의 목적은 e-learning을 통한 고교의 보충수업이 사교육시장에 미치는 영향을 분석함에 있다. 올해부터 시작된 EBS의 수능교육은 TV와 인터넷을 통하여 이루어지며, 사교육시장에 작지 않은 변화를 가져올 것으로 보인다. 연구방법으로는 EBS의 수능교육의 수요자인 고교생을 대상으로 설문조사를 수행하였다.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.662-663
• /
• 2011

수요자원시장은 '08년 시범사업을 시행하고, '09년부터 본 사업을 시행하였고, '10년도에는 51.3만kW의 부하감축을 시행하였다. 본 논문에서는 우리나라 전력수요자원시장의 기본개념 및 운영경험을 설명하고, 향후 전력수요자원시장의 개선방향에 대해 언급하고자 합니다.

• Annals of dermatology
• /
• v.30 no.6
• /
• pp.662-667
• /
• 2018

Background: Recently, the number of domestic pets has increased. As a consequence, sensitization to animal allergens, such as cat or dog allergens, has become a problem. Objective: We studied the annual trends of sensitization to cats or dogs, and the characteristics of the patients. Methods: We retrospectively analyzed the medical records of 7,469 patients who visited a dermatology clinic and underwent an allergic profile test, from January 2011 to December 2015. Specific immunoglobulin E (IgE) levels to cat or dog antibody greater than 3.50 IU/ml were regarded as positive results. Results: In all, 274 patients showed significant increase in levels of specific IgE antibody to dog, and 307 revealed increase in levels of of specific IgE antibody to cat. The prevalence of these specific IgEs increased from 2011 to 2015. Independent risks for sensitization to cat allergens were sensitization to dog, but not to house dust, Dermatophagoides pteronyssinus, and D. farinae. Independent risks for sensitization to dog allergens were sensitization to cat, but not to house dust, D. pteronyssinus, and D. farinae. Total IgE level was not related to specific IgE level against either cats or dogs. Conclusion: In conclusion, the prevalence of sensitization to cat or dog has increased. Sensitization to cat or dog is related to each other, but is irrelevant to the total IgE level.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2001.11b
• /
• pp.251-254
• /
• 2001

In this paper, we analyzed the properties change of electric wire when the thermal stress was applied to NFR-8 and FR-PVC 600[V] wire. Messurement is made of the attenuation of a light beam by smoke accumulating with in a closed chamber due to nonflaming pyrolytic decomposition and flaming combustion. Results are expressed in terms of specific optical density which is derived from a geometrical factor and the measured optical density a measurement characteristic of the concentration of smoke. Referenced documents were ASTM E662 standard test method for specific Ds genalated by solid materials. The furnace control system shall maintain the required irradiance level under steady-state condition with the chamber door closed of $2.5{\pm}0.04[w/cm^{2}]$ for 20 min. According to the results of the smoke density analysis of NFR-8 and FR-PVC the highest decomposition flaming smoke density range of NFR-8 and FR-PVC were 25.2 to 37.5 and 51.1 respectively. Nonflaming smoke density range of NFR-8 and FR-PVC were 100.4 to 112.2 and 126.5 to 398.8. The amount of carbon monoxide generated was found to be much higher in FR-PVC decomposition than in NFR-8 due to incomplete combustion of FR-PVC which has high content of carbon in compound.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2001.11a
• /
• pp.251-254
• /
• 2001

In this paper, we analysed the properties change of electric wire when the thermal stress was applied to NFR-8 and FR-PVC [600] wire. Measurement is made of the attenuation of a light beam by smoke accumulating with in a closed chamber due to nonflamining pyrolytic decomposition and flaming combustion. Results are expressed in terms of specific optical density which is derived from a geometrical factor and the measured optical density a measurement characteristic of the concentration of smoke. Referenced documents were ASTM E662 standard test method for specific Ds generated by solid materials. The furnace control system shall maintain the required irradiance level under steady-state condition with the chamber door closed of 2.5${\pm}$0.04[w/$\textrm{cm}^2$] for 20 min. According to the results of the smoke density analysis of NFR-8 and FR-PVC the highest decomposition flaming smoke density range of NFR-8 and FR-PVC were 7.2 to 77.5 and 51.1 respectively. Nonflaming smoke density range of NFR-8 and FR-PVC were 100.4 to 112.2 and 126.5 to 398.8. The amount of carbon monoxide generated was found to be much higher in FR-PVC decomposition than in NFR-8 due to incomp1ete combustion of FR-PVC which has high content of carbon in compound.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.12 no.4
• /
• pp.662-669
• /
• 1988

The acoustical characteristics of silencer has been investigated by experimental methods. The relations between various geometrical parameters, i.e. length, diameter, offset and twisting angle of silencers and transmission loss have been studied. The effect of mean flow on the transmission loss was also investigated. Results show that experimental decomposition of flow and sound is possible. Experimental results which take into account for the effect of mean flows provide the accurated data which have not been found in the literature.

• Parasites, Hosts and Diseases
• /
• v.43 no.2 s.134
• /
• pp.65-67
• /
• 2005

The intestines and hearts of dogs were examined for Toxocara canis, Toxascaris leonina, and Dirofilaria immitis, after necropsy between June 26 and September 29, 2004 in Chuncheon, Korea. Of the 662 dogs examined, 6 were infected with T. canis $(0.9\%),\;86\;with\;T.\;leonina\;(13.0\%)$. Fifty dogs were infected with D. immitis among 500 dogs examined $(10.0\%)$. Five were co-infected with T. canis and T. leonina, and three were co-infected with T. leonina and D. immitis. The cumulative positive infection rate for three species was $134/662(20.2\%)$. Considering previously reported seropositive rates of T. canis excretory-secretory antigen, i.e., $5\%$ in the adult population in Korea, the possibility of toxocariasis caused by T. leonina should be reevaluated.