• Fire Science and Engineering
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• v.16 no.1
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• pp.18-23
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• 2002

Efficiency estimation of toxicity free resistance cable experiments were conducts to understand toxicity free fire ersistance polyolefin insulation material and smoke density characteristic and combustion gas corrosion analysis. A main cause of fire-growth and generating toxic gas when it burns, should be dealt with great care in life safety design. Similar patterned fire incidents such as, Inchon Live-Hof Pub Restaurant as, Sea-land Children Resort have proven that serious loss of lives were caused by hazardous gas generated fire resistance cable materials. In this paper, 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$\pm40.04〔w/$\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 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. Also, the fire gases was occurred carbon monoxide and decomposition than in polyolefin due to incomplete combustion of PVC which has high content of carbon in chemical compound.

• The Korean Journal of Pharmacology
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• v.12 no.1
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• pp.63-67
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• 1976

The purpose of the present study was to see the Panax Ginseng has any influence upon the acquisition of the conditioned avoidance response(CAR) in rats. Sixty male rats of Holtsman strain were used. The animal weighed between 20 and 300 gm at the beginning of the experiment. Training of avoidance conditioning was done in a two-way shuttle box which was separated into two compartments by a guilotine door. The conditioned stimulus (CS) was a light beam and the unconditioned stimulus (UCS) was an electric shock. The shock was presented 10 sec. after onset of the CS and continued until the subject crossed to the opposite safety compartment within 20 sec. after onset of UCS. Each S was received 30 trials a day (one session) for 6 consecutive sessions. The number of CR which avoided successfully without having shock and the number of fecal balls during the conditioning were served as an index of learning performance and emotionality. The results obtained as follows. All doses of Ginseng saponin treated animals showed more CR than control, but did not differ significantly from control. Ginseng saponin treated animals with the doses of $50{\sim}100\;mg/kg$ defecated the fecal balls significantly less frequent than the placebo control during CAR.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.85-91
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• 2018

Recently, there have been a lot of casualties due to fires in high-rise buildings. The toxic gases and smokes generated by fires in high-rise buildings spread rapidly through the elevator shaft and stairwell, due to the stack effect, and can cause critical casualties. To reduce the number of casualties, smoke control systems have been introduced. Smoke control systems play an essential role in preventing the spread of smoke in high-rise buildings and securing the evacuation route. Also, in high-rise buildings, evacuation by an elevator is considered to be indispensable. However, the pressure field in the shaft is strongly disturbed when the elevator is moving and this can affect the performance of the smoke control system. Therefore, in this study, we experimentally and numerically analyzed the effect of elevator movement on the pressure difference between the vestibule and living room by building a model using the sandwich pressurization method based on the performance based design. To consider the leakage areas in high-rise buildings, e.g. the windows, fire door and elevator, the National Fire Safety Codes and area ratio were used. The elevator speed in the model building was varied between 20 m/s and 100 m/s corresponding to a real elevator speed of 7 m/s~17 m/s. As a result, the relationship between the pressure difference and elevator speed was found to be ${\Delta}P=40{\cdot}{\exp}$(-Ves /-104.7)-23.735. This result can be used to take into consideration the effect of elevator movement when designing smoke control systems.

• The Journal of the Korea Contents Association
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• v.15 no.3
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• pp.192-198
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• 2015

Checked out by the moving vehicle health checks for patients, practitioners, and the increase in radiation dose outside the vehicle, but an investigation into the leakage of radiation can still be negligible. In this study, through experimental results were as follows: Dose that occurs most often where the leak in the right door $1.14{\pm}1.75mR/h$, X-ray generator in terms of proximity to the top $0.65{\pm}1.25mR/h$, X-ray generator and away to the bottom in terms $0.91{\pm}1.25mR/h$, the adjacent rear detector in the upper part $96.98{\pm}158.88mR/h$ dose of the leak appeared in various locations. By measuring position from the rear of the adjacent detector $67.48{\pm}97.03mR/h$ dose had the highest leakage into. Generating device for diagnosis of radiation safety regulations regarding the maximum leakage dose per week, but all met back when it is displayed in the leakage dose Hourly rates do not ignore the leakage radiation dose were measured. Therefore, a mobile health screening in a vehicle outside of the leakage radiation dose to the liver and move on we are not interested twelve barrier leakage radiation dose of defense has a chance to re-evaluate the standards required, and move the vehicle health check using the X-ray increases as the dose per hour, depending on the criteria for choosing the appropriate measures that will require effort.

• Journal of the Korean Institute of Gas
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• v.19 no.1
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• pp.6-11
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• 2015

This paper is to study the examples for rubber damage and weaken reliability of timing belt, constant velocity joint boot and weather strip in vehicle. The first example, when the service man replaced the new timing-belt of rubber material, he assembled the belt that was weaken it's contact surface because of material transform. He knew the abnormally tearing failure by friction action between belt and sprocket. The second example, it certified the fact that the grease is leaked out boot protecting of constant velocity joint by split of rubber surface because of durability badness. The third example, the weather stripe took the minutely tearing because of damage produced the material transform by crack of chemistry change. It certified the production phenomenon of a tiny noise by coming with outside air because of overlapped the rubber of weather stripe when driving after closing the door. Therefore, the driver must always manage the rubber system part of vehicle.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5D
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• pp.437-444
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• 2012

This study intended to improve traffic safety in work zones using fluorescent orange color traffic signs. For this end, the current problems of existing traffic signs and facilities in work zones were analyzed and some good examples of foreign countries were compared. More specifically, in order to identify current problems, the basic shape and color of traffic signs in use were examined through literature review, surveys and field studies. It was found that the fluorescent color worked more effectively than other colors in terms of visibility and conspicuity in work zone sign system. For evaluation, both Conspicuity surveys and in-door simulator experiments were conducted to effectively assess the merits and demerits of different types of traffic signs for work zones. The results of evaluations showed that black lettering on a fluorescent orange background outperformed more than 70% in terms of visibility and ability to call drivers' attention compared with those from black/red lettering on yellow/white backgrounds currently used at work zones on expressways and national highways. In addition, simulated driving experiment disclosed that drivers recognized the fluorescent orange background sign 15m ahead compared with the yellow background sign and 25m ahead compared with the white background sign, respectively. As for the diamond-shaped "Under Construction" sign, drivers recognized fluorescent orange background 11m ahead compared with the yellow background sign and 19m ahead compared with the white background sign, respectively.

• Journal of the Korean Society for Railway
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• v.20 no.5
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• pp.569-576
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• 2017

The electromagnetic valve of pneumatic doors of EMUs has a high failure rate due to air leakage because it supplies air on and off to operate the doors repeatedly. The electromagnetic valve is a very important safety component for which a very high reliability is required because failure makes it impossible to operate the passenger cars. However, domestic urban railway operators maintain electronic valves of the EMU door under a fixed cycle with a spare period according to the full overhaul cycle of the EMU. An improvement of the current maintenance cycle was suggested based on the reliability function and mission reliability. Using the statistical program MINITAB for the operational data of EMU line 6, we analyzed the characteristics of the fault distribution and derived the shape and scale parameters of the reliability function. If we limit the specific reliability probability to under a certain failure rate and calculate its statistical parameters, we can calculate the allowable inspection period with mission reliability. Through this study, we suggested a maintenance period based on RCM (reliability centered-maintenance) to improve the reliability of electromagnetic valves from 68% to 95%.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.331-337
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• 2020

The study analyzes the appropriate number of people per a household by applying an evacuation simulation to a 27-floor apartment in accordance with the NFPA 101 standard. The results of the analysis are as follows. First, if there are three people residing in each household, there would be 156 households in total, of which 85.25% were evacuated within 5 minutes. Second, 208 households with 4 residents were evacuated within 5 minutes. Third, if there are five people residing in each household, there would be a total of 260 households and 71.92% of residents were evacuated within 5 minutes. Lastly, 62.82% of the 312 households, each consisting of 6 people, were evacuated within 5 minutes. Measures to reduce evacuation time include determining the width of the stairs according to the number of people indoors, the number of floors in the building, the slope of stairs, and the users' characteristics, the design reflecting the ventilation conditions of the stairs, the installment of outdoor evacuation stairs, two-way stairs, evacuation lift, and the installation of an evacuation safety zone for people to evacuate outside of the building in the middle floors. In addition, measures, such as the mandatory installation of automatic emergency door open-close device to the rooftop, are required to facilitate rooftop evacuation.

• International Journal of Railway
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• v.1 no.4
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• pp.143-148
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• 2008

This paper is the output of a collaborative European project concerning the barrier free accessibility for disabled persons to regional and long distance trains in Europe. Disabled people represent around 13% of the population in Europe. This is approximately 63 million people. The range of disabilities includes people with reduced mobility including wheel chair users, viewing and hearing impaired people and other forms of impairment. Improving accessibility aims at contributing to the provision of public transport services to all citizens in an equitable way. The purpose of the project was to analyse and to evaluate the existing solutions at selected European railways for all required modules at the entrance (doors, information and safety solutions), to derive a design concept, to develop a mock-up in meeting the needs of rail travellers with the above mentioned impairments and to test it with user groups. The project also aims at deriving components for the determination of standards. The EUPAX Design Mock-up test was performed to verify the advantages of the layout of the train segment including the different modules such as access area (including the access door, gaps between platform and train as well as boarding aid devices), entrance vestibule, information systems inside and outside the train, emergency facilities, toilet with all conveniences and the additional test arrangements regarding push buttons, steps and emergency equipment. For this purpose a questionnaire was developed for the assessment of the EUPAX segment and the additional test arrangements. With the help of this questionnaire it was possible to execute a quantitative and qualitative evaluation. During three test phases 67 experts and handicapped persons from 6 countries have evaluated the Industrial Design mock-up based on this questionnaire. The test group covered persons from North (Denmark) to the South (Italy) and from the West (Spain) to the Middle of Europe (Germany). This is especially important for the generalization (harmonisation) of the results for all European countries. According to COST 335 the information for people with reduced mobility should be clear, concise, accurate and timely. So that all information can be received from persons, they must be transferred on at least two of the three possible ways (acoustical, visual, tactile), a so called "2-sense-principle". Based on the results ergonomic specifications/ solutions for the ergonomic design of the access area, the acoustic, visual and tactile information and the emergency devices including the emergency communication system were developed, related to the benefiting passenger groups.

• Journal of Energy Engineering
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• v.23 no.2
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• pp.207-216
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• 2014

The energy loss can be divided into the loss caused by heat transfer and the loss caused by air flow. Heat transfer is the loss resulting from the heat transmittance of external wall, roof, and floor, and represents one of the most vulnerable elements of existing buildings. To prevent such loss, it is necessary to increase the mean heat transmittance of entire external wall, including the window, to a level above the standard regional value and ensure the air-tightness of window. The old buildings have the structure which is prone to the loss of greater air flow due to the air infiltration through the exit/entrance door upward along the stairway by the stack effect and simultaneous suction of air from each floor, and becomes even vulnerable to the loss of heat insulation for each floor, although the external wall and windows are the most vulnerable parts. The improvement plans for each floor need to be submitted in tandem with the diagnosis of whole building, regarding the diagnosis plan and energy improvement measures based on the survey of site, rather than adhering to the misconception that the replacement of window alone will result in energy-savings.