• Horticultural Science & Technology
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• v.31 no.1
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• pp.8-13
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• 2013

This research was conducted to investigate the effect of climatic factors on fruit growth in 'Niitaka' pear (Pyrus pyrifolia). For ten years from 2000 to 2010, average full bloom date was April 19th and standard deviation was 4.2 days. Average fruit diameter 160 days after full bloom (DAFB) was 102.4 mm and standard deviation was 7.5 mm. Variance coefficients among climatic factors were higher in rainfall amount and sunshine hours than temperature. Only sunshine hours of climatic factors accumulated during the 160 DAFB had significant positive relationship ($r=0.68^*$) with fruit diameter 160 DAFB. Between full bloom date and fruit diameter 160 DAFB had no significant relationship. Fruit growth in 2004, as continuous rain fall and short sunshine hours, showed opposite pattern compared to that in 2009. Therefore, fruit growth of 'Niitaka' pear was more influenced by the accumulated sunshine hours than accumulated temperature.

• Fire Science and Engineering
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• v.29 no.1
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• pp.80-86
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• 2015

This study analyzed recent cases of ship fires explosions and investigated their problems and coping plans. Through analysis on the statistical figures, it was found that our nation's situations of maritime accidents by kind during the period of 2009~2013 showed the ratios of ship accidents caused by fires explosions was the highest in 2012 with 7.58% (55 cases) followed by year 2009 with 3.39% (34 cases), year 2010 with 3.39% (25 cases), year 2011 with 6.03% (57 cases) and year 2013 with 6.74% (43 cases), which indicates a steady increase in the number of ship accidents. Majority of reasons for ship fires explosions were lack of safety awareness. Since those accidents happen on the sea, fires, once they happen, tend to get serious due to absence of on board & nearby fire extinguishing facilities, public fire service's uneasy access to them and great influences of natural factors such as wind and etc. Ship fires explosions are special cases unlike what happens to general edifices. So, their coping plans should focus on preventive measures since the damages those cases bring about can be detrimental. For this reason, it's necessary to research precise evacuation plans, develop ship structure & materials reinforcing fire resistance to secure more time for evacuation and enhance people's safety awareness by implementing thorough safety training.

• Fire Science and Engineering
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• v.29 no.1
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• pp.38-44
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• 2015

This study suggested the problems and their improvement measures for the operation of fire detectors and sprinkler heads installed at apartment houses. According to a census on population and housing in 2010, apartment houses account for 71.6% of the total housing facilities. And by fire statistics data of the National Emergency Management Agency, approximately 25.0% of fire accidents and 46.4% of casualties occur at apartment houses every year. Therefore, this study conducted for identifying the causes and characteristics of fire to establish the fire safety improvement measures for apartment houses. And this study was carried out virtual fire simulation at domestic apartment houses. The scenario of the simulation contains a comparative analysis on the operation time of standard sprinkler heads and residential sprinkler heads, heat detectors and smoke detectors. As a result of simulation, it was found that standard sprinkler heads and heat detectors installed at the existing apartment houses should be replaced with residential sprinkler heads and smoke detectors for rapid fire suppression. In addition, sprinkler systems should be considered to be installed for excluded floor at apartment houses. Especially, it is necessary to construct remote inspect systems like advanced countries for efficiency of apartment houses safety management.

• Fire Science and Engineering
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• v.25 no.2
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• pp.39-46
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• 2011

In correctional facilities with majority of occupants in custody, the safe evacuation guide without getaway accidents should be very important due to complexity in escape paths. Fire causes are various in correctional facilities, for example, arson fire is a major cause in mental treatment facilities, however, old facilities or carelessness of flammable materials consist of fire causes in jail facilities. Both types of correctional facilities are the same in terms of many casualties from the fire cases. The thesis focus on escape paths and evacuation guide plans on the basis of analysis on fire cases and structural vulnerability, and then an electronic unlocking system is concededly installed for safe evacuation of occupants in custody without getaway accidents. Especially, the effect of the electronic unlocking system is going to be analyzed on the basis of RSET (required safe egress time) in order to realize for the occupants to evacuate safely to the front yard in case of emergency. In conclusion, if electronic security allowed system with USN (Ubiquitous Sensor Networks) technology should be installed in multi-storey correctional buildings, it is proposed that the occupants in custody might be a guided safely without getaway trials.

• Fire Science and Engineering
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• v.31 no.5
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• pp.37-43
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• 2017

Domestic sandwich panel buildings are widely used on walls and roofs of factories and warehouse facilities. Factory and warehouse facilities have high fire load and rapid spread of fire due to their use characteristics, leading to large fires. Due to the characteristics of materials, walls and roofs are collapsed, resulting in life damage and property damage. In this regard, this study examined domestic and international standards of sprinkler facilities to prevent ignition of sandwich panel walls. Also, in order to check whether the fire was prevented by installing the head on the wall of the sandwich panel, the fire test was carried out with 10 cm, 60 cm, and 120 cm from the wall along the sprinkler head installation standard of domestic fire safety standards. As a result of the fire test, it was confirmed that the sandwich panel was prevented from igniting when the head of water pressure 0.1 MPa and water quantity K-80 was installed. According to the separation distance, it was impossible to measure the temperature at 10 cm, but at 60 cm, At the maximum temperature of $525^{\circ}C$ and 120 cm, the maximum temperature of the wall of the sandwich panel was measured as $276^{\circ}C$. As a result of the fire test, considering the fire point of 450 degrees Celsius in the fire test of the sandwich panel, the distance from the sandwich panel wall to the combustible is more than 120 cm.

• Fire Science and Engineering
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• v.31 no.4
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• pp.80-85
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• 2017

Recently, in Korea, construction of high-rise buildings has been rapidly increasing. Therefore, in order to minimize the loss of life and property in the event of a fire, "performance-based design" which requires performance equal to or better than current regulations is obligatorily required. However, in the field of fire and evacuation simulation, which occupies a large part in the performance-based design, detailed technical guidelines have not yet been established. Therefore, various designers are proceeding with the computer simulation modelling by referring to the design report book previously performed. Especially, in the case of the fire simulation, according to the judgment of a designer the scenario type is selected and the input values is set. Even if the building is used for the same purpose, it is true that the result can be different depending on how and who designed it. Therefore, in this paper, we have investigated the fire scenarios type and scenarios input values by randomly examining 7 preliminary reports of performance-based design in B metropolitan city. We also propose the improvement strategy for fire simulation and lay the groundwork for establishment of technical guidelines for fire simulation for performance-based design.

• Fire Science and Engineering
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• v.32 no.3
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• pp.67-75
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• 2018

To reduce the number of casualties in the case of fire, an alarm sound needs to be delivered to the people who remain in the apartment unit. On the other hand, it was reported that the fire alarm sound generated in the elevator hall was not delivered sufficiently to the people staying in the apartment units. In this study, the background noise level and noise level generated in an apartment unit were measured during the day and night time. In addition, the transmission of the fire alarm sound into the each room of apartment units was simulated and compared with the background noise level. The fire alarm sound generated in the elevator halls was reduced by the fire door and doors, and was not transmitted sufficiently into the internal spaces of the apartment units. Starting evacuation action was difficult after hearing the fire alarm sound generated outside the apartment units. To improve the transmission of an alarm sound to the inner spaces of apartment units, an acoustic simulation was carried out for cases where the alarm sound generator was installed on a wall-pad in the living room and the alarm sound generator was installed on the ceiling of each rooms in apartment units. Background noise of + 15 dB and 75 dB (A) were satisfied when alarm sound generator was installed on the ceiling of each room.

• KIPS Transactions on Computer and Communication Systems
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• v.5 no.9
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• pp.211-216
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• 2016

Worldwide casualties caused by earthquakes, floods, fire or other disaster has been increasing. So many researchers are being actively done technical studies to ensure golden-time. In this paper if a disaster occurs, use the IoT technologies in order to secure golden-time and transmits the message after to find the user of the accident area first. When the previous job is finished, gradually finds a user of the surrounding area and transmits the message. For national emergency information, OPEN API of Korea Meteorological Administration was used. To collect detailed information on a relevant area in real time, this study established the system that connects and integrates Crowd Sensing technology with BLE (Bluetooth Low Energy) Beacon technology. Up to now, the CBS based on base station has been applied. However, this study designed and mapped DB in the integration of Beacon based user positioning and national administrative address system in order to estimate local users. In this experiment, the accuracy and speed of information dif6fusion algorithm were measured with a rise in the number of users. The experiments were conducted in a manner that increases the number of users by one thousand and was measured the accuracy and speed of the message spread transfer algorithm. Finally, became operational in less than one second in 20,000 users, it was confirmed that the notification message is sent.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.16-23
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• 2020

Water pipes are important facilities and consist of pipes of various specifications and materials. The annual average number of earthquakes in Korea is steadily increasing. Therefore, in case of the water pipe, it is estimated necessary to prepare for earthquakes. Damages to the water pipe by the earthquake can cause problems such as water supply and fire suppression, and cause damage to life and property. In Korea, however, it is difficult to find examples of seismic performance evaluation of water pipes based on experimental study. Damage to the water pipes by the earthquake is caused by the displacement-controlled behavior of the ground which is the liquifaction and fault lines. Especially, The damage to the water pipes by the earthquake is concentrated on the joint of the pipe. In particular, piping less than 200mm in diameter was found to be dangerous. Thus, in this study, the seismic and settlement performance of iPVC buried water pipes with fixed joints with a clamp of 150mm was evaluated with a test approach.

• Journal of the Korean GEO-environmental Society
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• v.15 no.2
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• pp.37-43
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• 2014

Natural disasters such as earthquakes and tsunamis occur suddenly, so that they cause massive loss of lives and property. Especially earthquakes represent a particularly severe threat because of the extensive damage accompanied by them. In Korea, an earthquake-resistant design has been rarely applied to a design or construction of slope. However, in resent years, the researches for earthquake-resistance have been performed because the importance on the earthquake-resistance is perceived and highlighted. Soil nail method, one of the slope stability methods, is excellent for its constructability and cost effectiveness, as compared with other stability methods. Also, this method has been widely used for reinforced construction for slope stability. The studies of soil nail method have been performed on the interaction behavior between nails and slopes as well as the varied load condition such as static load, dynamic load and so on. Nevertheless, there has been minimal research regarding the constraint condition of nail head. In this study, the numerical analysis was performed for identifying effect on slope stability for the constrain condition of the soil nail. The result shows that the resistance of constrained the nail head on reinforced slope is larger compared to the one of unconstrained nail head.