• Archives of Plastic Surgery
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• v.35 no.2
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• pp.147-151
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• 2008

Purpose: The purposes of the authors' analysis were to assess the values that plastic surgery journals demonstrate in terms of the standardized measures created by the Korea Medical Citation Index, and to assess the relationship between these values and the turnaround time of these journals. Methods: The overall indexes of J Korean Soc Plast Reconstr Surg(JKSPRS), J Korean Soc Aesthetic Plast Surg(JKSAPS), J Korean Cleft Palate-Craniofac Assoc (JKCPRA) were compared with those of journals related with Korean plastic surgery using the following parameters: impact factor, cited half-life, total articles, and the number of journals. Korean plastic surgery journals were compared with journals from relative fields. In addition, an evaluation of all original articles published in 2007, assessing the time intervals from submission to publication was conducted for Korean plastic surgery journals and various journals which were related with plastic surgery. Results: The number of articles for Korean plastic surgery journals for 2006 ranged from 19 for JKCPRA to 149 for JKSPRS. The time interval from submission to publication of an article among Korean plastic surgery journals for 2007 ranged from 73.7 days for JKSAPS to 176.2 days for JKSPRS. The variation in impact factor of JKSPRS for the period from 2002 to 2005 increased from 0.084 in the year 2002 to 0.168 in 2005. But the impact factor in 2006 has fallen to 0.112. Conclusion: JKSPRS demonstrated comparatively high overall index values and a short turnaround time in comparison to relative journals. To improve the status of Korean plastic surgery journals, members of Korean plastic surgeons should quate Korean plastic surgery journals and adjust key word to MeSH. The title written down in Korean should use medical terminology published by Korean medical association.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.1
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• pp.30-39
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• 2004

This research is of the rapid industrialization taking place resulting in the destruction of forests. The method that is implemented needs the vegetation to work well with the topsoil in order to restore the environment. In November the researcher collected a depth of 5 cm of topsoil from a well developed forest, after the fallen leaves were cleared. The results of the essential research are as follows : In the case of using the forest topsoil to plant trees latency seeds, during the early stages of tree planting, time is necessary for the desired vegetation to reach a similar state to the vegetation being restored. The results conclude that the best possible affect is obtained through a method utilizing seeded species. Utilizing forest topsoil, slopes that have been too damaged for trees to be planted can be sown with seeds. In addition the rearing of naturally-emerging species had a tendency to decline. When considering rearing naturally-emerging species to flourish in the topsoil, in the early stages of tree planting, the beginning foundation of sowing seeded species has to have a standard of about 1,000parts/$m^2$ This standard has been found to the most successful.

• Journal of the Korean Society for Heat Treatment
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• v.12 no.2
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• pp.145-156
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• 1999

The distribution of the second phase, the change of transformation temperature and mechanical properties with thermomechanical treatment conditions were investigated by metallography, calorimetry, EDS, tensile test and fractography in a Cu-Al-Ni-Ti-Mn alloy. The cast structure revealed Ti-rich precipitates($X_L$ phase) between dendrite arms, which have been identified as $(Cu,Ni)_2TiAl$ intermetallic compounds. By homogenizing above $900^{\circ}C$, the $X_L$ phase was melted in the matrix, while the Xs phase was precipitated in matrix and the volume fraction of it was increased. When hot-rolled specimen was betatized below $750^{\circ}C$, recrystallization could not be observed. However, the specimen betatized above $800^{\circ}C$ was recrystallized and the grain size was about $50{\mu}m$, while Xs phase was precipitated in matrix. With raising betatizing temperature, $M_s$ and $A_s$ temperatures were fallen and transformation hysteresis became larger. The strain of the specimen betatized at $800^{\circ}C$ was 8.2% as maximum value. The maximum shape recovery rate could be obtained in the specimen betatized at $800^{\circ}C$ but it was decreased due to the presence of Xs phase with increasing betatizing temperature.

• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.575-580
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• 2010

Forest fires in Korea, having forest coverage of 70%, have kept increasing in number and scale since the middle of 1990's. Although deposited fallen leaves in forests such as herbaceous plants, conifers, and broadleaf trees are used as a medium for forest fires, the pyrolysis and combustion characteristics of the various species of trees are hardly studied. Oriental oak is the representative broadleaf tree in domestic forests, and pyrolysis and combustion of oriental oak leaf were carried out by thermogravimetic analysis (TGA). The leaf of oriental oak was ignited at $239^{\circ}C$ whereas pyrolysis started at $250^{\circ}C$. The corresponding kinetic parameters including activation energy and pre-exponential factor were determined by differential method over the degree of conversions. The values of activation energies for pyrolysis were increased as the conversion increases from 10% to 80%, whereas those of values were decreased during combustion.

• Fire Science and Engineering
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• v.28 no.6
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• pp.22-27
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• 2014

In this study a Fuel bed where surface fire spreads through is made to measure the data such as the flame height, radiation, spread rate and temperature distribution of Fuel bed. As experimental variables species of trees, wind velocities and slop are chosen. Fallen leaves of Quercus Variabilis (Q.V.) and Pinus Densiflora (P.D.) are used as fuel. Wind velocity is controlled by simply designed wind turnnel from 1 to 5 m/s. Slope of fuel bed is changed from $0^{\circ}$ to $30^{\circ}$. For the measurements of temperature distribution and spread rate total 35 of K-type 1.6 mm thermocouples are positioned as a lattice design. Radiant heat flow meters are used besides video camera and thermovision camera.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.1
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• pp.3655-3665
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• 1975

This study was intended to develop a method for measuring the grain separating performance of threshers. The grain separating apparatus used for the experiment was designed and constructed, the function of which was to separate pneumatically mature and immature grain, chaff, straw, dust, and other impurities from the products of threshing. The apparatus has five material outlets where grains and impurities are fallen down by separation depending upon the specific gravity of the material white it moves above the outlets. The principle of design was to separate the mixture of mature grain, immature grain and chaff as distinct as possible, and to induce the mature grains onto the first outlet, the immature grains onto the second and the third, and the straw wastes onto the forth and the fifth outlets. The developed apparatus was tested to evaluate its separating performance with two rice varieties (Tongil and Mine-hikari) at different moisture levels and air velocities. The optimum conditions for operating the apparatus were found from experiment. The results are summarized as follows; 1. The degrees of separation, especially the amount of immature grain contained in the mature paddy, were dependent upon air speed delivered. The optimum air velocities for this apparatus for each levels of grain moisture contents were found from a series of experiments as follows; 14.7-15.3m/sec. for grain of 16 percent moisture content in wet basis, 15.3-16.0m/sec. for 20 percent, and 16.0-16.4m/sec for 24 percent. 2. Composition ratios determined based on the brine separating method was fairly well acted upon the developed apparatus, indicating its recollecting rate of the mature grains as 97.6 to 99.9 percent. The developed separatus acted similarly upon the two rice varieties which had different composition of immature paddy grain. In other words, the separating performance by the apparatus had a good correlation with the one by the brine separating method. 3. As immature grains were separated out unsatisfactory in these experiments than the brine separating method, further investigation may be needed to improve a separating performance of these materials. But the results obtained suggested a possibility of using the tester to replace the current hand separating method, ther eby enabling more consistent test results and also eliminating nearly all costly hand seperating operations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.2
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• pp.388-394
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• 2008

In this paper, MAC(Medium Access Control) algorithm for the IEEE 802.11 DCF(Distributed Coordination Function) improving the performance is proposed and analyzed by simulation. The MAC of IEEE 802.11 WLAN to control data transmission uses two control methods called DCF and PCF(Point Coordination function). The DCF controls the transmission based on CSMA/CA(Carrier Sense Multiple Access With Collision Avoidance). The DCF shows excellent performance relatively in situation that competition station is less but has a problem that performance is fallen from throughput and delay viewpoint in situation that competition station is increased. This paper proposes an enhanced DCF algorithm that increases the CW to maximal CW after collision and decreases the CW smoothly after successful transmission in order to reduce the collision probability by utilizing the current status information of WLAN. To prove efficiency of proposed algorithm, a lots of simulations are conducted and analyzed.

• Fashion & Textile Research Journal
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• v.2 no.5
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• pp.416-422
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• 2000

In this study, to find out the physiological reaction of the human body and the sensation of comfort when people are wearing sportswear which is made of waterproof breathable fabrics under general environmental conditions (temperature : $20{\pm}1^{\circ}C$, humidity : $60{\pm}5%RH$, air current : 0.1 m/sec) and rainy environmental conditions (temperature : $20{\pm}1^{\circ}C$, humidity : $60{\pm}5%RH$, air current : 0.1 m/sec, rainfall : 250 1/hr), we made an experiment with sportswear in an artificial climate chamber and studied the thermal physiological response and subjective sensation. Mean skin temperature of the subjects was low and had a big range of fluctuation in rainy environmental conditions of two condition. Temperature started to increase at the beginning of the exercise, reached the maximum at the 2nd level of the exercise and then started to decline. Rectal temperature showed a slighter increase and bigger range of fluctuation in general conditions than in rainy conditions. Except clothing micro climate in rainy conditions, temperature and humidity and their range of fluctuation around back were higher than those around chest. Humidity was high and had wide range of fluctuation in general conditions. Heart rate was 4.4 beats/min higher in general conditions. In subjective test on rainy conditions, the feeling of discomfort increased due to the raindrops fallen on the skin. Unlike that in general conditions, cold sensation increased and humidity sensation reached to the peak after the exercise. In wearing sportswear made of shape memory breathable waterproof fabric, controlling function over a small amount of heat and water was distinctive while it turned out to be not so comfortable over a large amount of heat and water. Through this, the limitation of shape memory breathable waterproof fabric was recognised.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.4
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• pp.590-602
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• 2019

Objectives: This study was conducted to prevent asphyxiation of firefighters during confined space rescue. The specific purpose was to identify the magnitude of the problem, identify the cause of the accidents, and suggest measures to ensure safety of confined space rescues. Methods: We collected data from National Fallen Firefighters Memorial, press releases, and other sources In order to identify the current situation of asphyxiation incidents among firefighters from 1945 to 2019. In addition, an incident investigation was conducted for each case, and the processes, causes, and control measures of the incidents were described as a narrative data entry. Results: Over the past 73 years, eight incidents involving firefighter in Korea have occurred. In these incidents, five firefighters were killed, and eight were injured. The confined spaces incidents occurred were water supply tanks, wastewater treatment tanks, pickling pits, septic tanks, and more. The causes were three cases of hydrogen sulfide poisoning, one of oxygen deficiency, one of carbon monoxide poisoning, and three unclassifiable asphyxiations. The people in need were all workers in various industries. Conclusions: The number of firefighters' deaths and injuries during rescues in confined spaces was severe and the risks have not been completely eliminated. By establishing and implementing a precise incident investigation system, according control measures should be initiatedin order to prevent a recurrence of the same type of disaster and reflected in the SOP. In particular, due to the high risk of occurrence at workplaces, cooperation between fire and rescue authority and relevant agencies such as the Ministry of Employment and Labor and the KOSHA should be strengthened.

• Analytical Science and Technology
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• v.8 no.4
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• pp.799-806
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• 1995

In industrial field, a large volume of regenerants (acid and caustic soda) and their washing effluents are regularly disposed off from the water demineralization plant during regeneration of the ion-exchanger units. Of these waste effluents, a part of the wash water discharged from the single bed Anion and Mixed Bed units can be utilized at a certain stage of their washing cycles when its conductivity is fallen down and becomes considerably less than that of the input raw water. The main aim of this specific waste effluent utilization is to dilute the TDS concentration of the input raw water (fed into the single bed ion-exchanger units) by blending. The achievement is the increase of the longevity of the production cycles of the I.E. units along with the improvement of the production quality and decrease of the regeneration frequencies. As a result, regenerant consumption would be saved because of the reduction of ionic load in feed water which will ultimately reduce the water purification cost. At the same time, the environment pollution will also be protected to a considerable extent. This operational measure is quite effective and useful specially where high TDS water is demineralized only by single bed ion-exchangers. In such case, the water treatment plant is very often found to suffer from both production quality and quantity in addition to carrying out of random and restless regenerations. Proper reuses of the aforesaid wash water effluents of the Anion and MB units excellently minimizes the difficulties experienced in practice. This paper contains the utilities and techniques of reuses of the different kinds of waste effluents of the industrial water treatment plant in addition to the specific reuses of the post-regeneration wash waters of the Anion and MB ion-exchanger units.