• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.6
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• pp.601-607
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• 2015

The friction material for automobile is manufactured by mixing several composites to stop the running vehicles. Friction characteristics are changed significantly according to the relative amount of the base materials. However, difference of friction coefficient is sometimes measured at the test for the same friction material. Nevertheless, the study for solving these problems is insufficient. In this paper, the friction tests were carried out by changing the external environment and processing condition when the main ingredients are fixed and also evaluated how the friction coefficient changes. The variables are cooling air speed, humidity (Relative humidity and Absolute humidity), scorching time, soaking time and pad area. And it is analytically considered which environmental factor mainly affects the characteristic of friction coefficient variation by experiment. It is expected that the results from this study can be very useful as a database for development of the friction material.

• Journal of the Korean Wood Science and Technology
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• v.49 no.1
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• pp.82-92
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• 2021

Nakdong technique is an unfamiliar scorching treatment using an iron heated in a kiln over 1000℃. It is a typical convention in Asian countries to treat Nakdong on the surface of paulownia species. The scorching treatment changes the surface characteristics as well as the color of the wood. This study focused on the effects of functional features such as water resistance, anti-mold, anti-termite, and sound improvement because this treatment is usually used on paulownia wood-bodied musical instruments surface. It took 28'57" for Nakdong-iron treated surface to absorb a droplet of water. The absorbance time of iron treated surface was longer than that of torch treated one. There was no noticeable effect on the anti-mold test. On the anti-termite test, there was nearly 3% more mean mass loss on the torch samples than controlled and iron treated ones. In examining the sound radiation coefficient before and after Nakdong treatment, the Nakdong-iron treated surface showed an increase in the average value of 1.2 m4/kg s, which means that it has sound quality improvement. Through this research, the Nakdong technique results are expected to be used as basic-data for further research and give a practical idea for using the traditional treatment method on the wood surface.

• Journal of Environmental Science International
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• v.23 no.12
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• pp.2029-2034
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• 2014

To improve air quality around a broad way, Daegu Metropolitan city employed the clean-road system at a part of the broad way of Dalgubul (Daigubul-daero) in 2011. The clean-road system in general is operated two times (4 am, 2 pm) during summertime. In case of scorching alert, the system is operated 3 times a day (4 am, 2 pm and 4 pm). To evaluate the effect of air quality improvement due to the system, we analyzed the time variation of monthly mean particulate matter (PM10) concentration in recent 3 years (2011-2013). The improvement of air quality was estimated at about 5~15 % under the system.

• Journal of Environmental Science International
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• v.24 no.9
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• pp.1171-1180
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• 2015

To investigate thermal environment and effect of clean-road system over a broad way, we conducted the filed meteorological observation during 12~13 August 2014. The clean-road system was employed over a part of the broad way of Dalgubul(Dalgubul-Daero) by Daegu Metropolitan city in 2011. The clean-road system in general is operated two times(4 am, 2 pm) during summertime. In case of scorching alert, the system is operated 3 times a day(4 am, 2 pm and 4 pm). To evaluate the present thermal condition and the improvement effects due to the system, we analyzed the time variation of discomfort index and WBGT(wet-bulb and globe temperature). WBGT was more than 25 during 8 a.m. ~ 9 p.m. And discomfort index was more than 75 during 8 a.m. ~ 11 p.m. The thermal improvement effect of the clean-road system was restrictive during daytime.

• Journal of the Korean Applied Science and Technology
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• v.32 no.3
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• pp.427-438
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• 2015

The effects of different feeding times, using a diet containing 800 ppm betaine, on production, blood profile, and the short-chain fatty acid (SCFA), was investigated using 240 Cherry Valley (Anas platyrhynchos) meat ducks exposed to a scorching heat wave. The animals were randomly assigned to four groups, each of which was replicated three times with twenty ducks per replicate. The experimental period was 42 days for each group. Four groups were assigned into C (heat wave control group without betaine), T1 (ad libitum group fed a diet containing 800 ppm betaine), T2 (diet-restricted group fed twice daily between 05:00-10:00 and 17:00-20:00, using a diet containing 800 ppm betaine), and T3 (night-restricted group, fed from 17:00-10:00, with a diet containing 800 ppm betaine). At 42 days, body weight increased in order of T2, T1, T3 compared to the heat wave control group although. However, these differences were not found between the groups of T1 and T3. The heat wave control group, provided an ad libitum diet without betaine (C), showed an elevated feed conversion ratio compared to the groups fed a diet containing betaine. However, these differences were not found between the groups of T1, T2 and T3. RBC and platelet profiles except for PLT and MPV showed statistically significant differences between study groups fed a diet containing betaine. T2 presented significantly higher blood electrolytes $Na^+$ and $Cl^-$ than the other groups. T2 also showed a blood gas level that was generally higher than the other groups. Total SCFA, acetic acid and propionic acid concentration has been the increasing trend in T2, but butyric acid, isobutyric acid and valeric acid concentration has been the decreasing trend in T2 compared to the other groups. It is concluded that the feeding-restricted group, fed two times daily between 05:00-10:00 and 17:00-20:00, with a diet containing 800 ppm betaine may improve growth performance in meat ducks exposed to a scorching heat wave.

• KIEAE Journal
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• v.15 no.3
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• pp.5-14
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• 2015

Purpose: Recently, according to climate changes, human health is exposed to danger over the world and they influence all fields of human society. Due to these climate changes, humans can be exposed to more frequent and extreme scorching heat and cold wave than the present. As precautions against these urban higher temperature and dryness, diverse methods are being sought. Among them, as measures to form cold islands, the evaporative cooling effect realistic to social and economic conditions was examined. Method: This study was conducted to analyze effects of temperature reduction and cooling according to injection quantity of minute water particles by using a blast sprayer as one of alternatives of alleviation of urban climate changes in outside space in summer. For this, through temperature difference in accordance with the injection quantity per hour of a day, a time zone representing the value of the highest temperature change was analyzed. Also, by analyzing temperature difference according to the injection quantity per daytime insolation, relation of amounts of insolation and evaporation was investigated. Temperature difference in accordance with distances at the highest temperature with the highest value in temperature changes was analyzed. Result: At the study result, about temperature, as injection quantity increase, temperature reduction was significant statistically at the highest temperature with the most insolation. A factor with the highest influence was judged to be the increase of the injection quantity. According to the injection quantity, it was predicted that $3.1^{\circ}C$ temperature reduction of a daily average in case of 0.16L/min, $3.5^{\circ}C$ temperature reduction of a daily average in case of 0.32L/min, and $4.4^{\circ}C$ temperature reduction of a daily average in case of 0.48L/min.

• Journal of Korean Medical classics
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• v.24 no.2
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• pp.23-50
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• 2011

"LeiGongPaoZhiLun" is the first pharmaceutical book, and there are various opinion on when LeiXiao(雷斅), the author lived. From the aspect of several data, it is appropriate most that LeiXiao live in the period of Sui(隋) Dynasty, like SuSong(蘇頌) in the Sung Dynasty said, This book was not made at one time by one person. At the beginning, it was written by LeiXiao and the later generations enlarged to finish. The original of "LeiGongPaoZhiLun" disappeared already but a large amount of this book was quoted to "ZhengLeiBenCao(證類本草)" to be preserved. The contents of "LeiGongPaoZhiLun" are the first professional book about processing of medicinal, in which most of processing of medicinal that is generally used today, is included and some methods are unused. Besides, the regulations of this book are specific, the range is broad, and theoretical frame is established for the first time. This book has abundant contents, in which several processing of medicinal are written. There are 10 methods such as steaming(蒸法), boiling(煮法), baking(炮法), stir-frying(炒法), calcining(煅法), long time boiling(煉法), scorching(燒法), baking after wrapping(煨法), immersing(浸法), washing(洗法), flying(飛法), etc. How to remove some section that is not used for drug, how to separate according to medical use and region to be applied, how to smash, how to cut, how to dry, container for medicine, warning for making a prescription, time to make medicine and amount of medicine, how to distinguish superior and inferior and origin, how to make medicine partially, etc, are contained in this book. The contents of "LeiGongPaoZhiLun" can be mixture of processing of medicinal of medical scientists and taoists. In conclusion, however, the effect by the later medical generations of "LeiGongPaoZhiLun" was not great on processing of medicinal. It stemmed from the difference of processing of medicinal in this very taoistic book that realistic difficulties were disregarded by taoists for training and practical purpose, treatment that is the reason that later medical generations used processing of medicinal. Consequently, there is no great relation between the development of processing of medicinal in the Sung Dynasty and this book. "LeiGongYaoXingFu(雷公藥性賦)" that was abundant in medical market in Ming(明) and Qing(清) period has no relation with "LeiGongPaoZhiLun" is kind of a distribution-purposed book that was mnge in or after Ming Dynasty. However, since a book that is said to be written by 'LiGao(李杲)'PaoZhihis nof a dijust borrowed and focus on a brief summery, it is not desirable for beginners to learn medical knowledge. "LeiGongPaoZhiLun" is the first pharmaceutical book and is a model to show how a science in the history of the herb medicine generated and developed and how such a book is changed and modified to make a change of value.

• Culinary science and hospitality research
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• v.20 no.6
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• pp.254-261
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• 2014

In order to optimize process conditions for manufacturing retorted Kimchi soup by using stationary and rotary types systems were applied for sterilization process. For investigating the differences in heat penetration characteristics during sterilization, Kimchi soup was packed into retort pouches, and sterility ($F_0$ value) at various positions in the product was measured through a wireless $F_0$ sensor. Heat penetration characteristics were significantly affected by sterilization method. From data analysis, optimum ranges of sterilization temperature and time was determined to be $120.7^{\circ}C$, 13 min for rotary type and $120.7^{\circ}C$, 20 min for stationary type. At those conditions, they had similar sterility ($F_0$ value). The results showed that rotation provides faster heat penetration and more uniform sterility than various positions of the product. These results derived a lot of advantages from related industry. For instance, many of the more viscous semi-liquid products and heat sensitive natural products could be sterilized in the lager pouch sizes without overcooking or scorching. Hence, current study suggests that rotary type retort would make it possible not only to reduce processing times as 35~45%, but also to improve the quality of product as overall taste, flavor, color, and texture with significant difference (p<0.05).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.283-290
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• 1982

Sardine and mackerel so called dark muscled fish have been underutilized due to the disadvantages in bloody meat color, high content of fat, and postmortem instability of protein. Recent efforts were made to overcome these defects and develope new types of product such as texturized protein concentrates and dark muscle eliminated minced fish. Approach of this study is based on the rapid dehydration of foamed fish-starch paste by dielectric heating. In process comminuted sardine meat was washed more than three times by soaking and decanting in chilled water and finally centrifuged. The meat was ground in a stone mortar added Ivith adequate amounts of salt, foaming agent, and other ingredients for aid to elasticity and foam stability. The ground meat paste was extruded in finger shape and heated in a microwave oven to give foamed, expanded, and porous solid structure by dehydration. Dielectric onstant $(\varepsilon')$ and dielect.ic loss $(\varepsilon")$ values of sardine meat paste were influenced by wavelength and moisture level. Those values at 100 KHz and 15 MHz were ranged 2.25-9.86; 2.22-4,18 for E' and 0.24-19.24; 0.16-1.20 for E", respectively, at the moisture levels of $4.2-13.8\%$. For a formula for fish-starch paste preparation, addition of $20-30\%$ starch (potato starch) to the weight of fish meat, $2-4\%$ salt, and $5-10\%$ soybean protein was adequate to yield 4-5 folds of expansion in volume when heated. Addition of e99 yolk was of benefit to micronize foam size and better crispness. In order to provide better foaming and dehydration, addition of $0.2-0.5\%$sodium bicarbonate, foaming agent, was proper to result in foam size of 0.5-0.7 mm and foam density of $200-400\;/cm^2$ which gave a good crispness. Heating time was depended upon the moisture level of fish-starch paste. For a finger shaped paste (1.0cm. $D\times10cm.L$) heating for 150-200 sec. in a microwave oven (700W. 2.45GHz) was sufficient to generate foams, expand, and solidify the porous structure of fish-starch paste. When the moisture content was above $55\%$ browning and scorching was deepened due to over-expansion and over-heating whereas the crispness was hardened by insufficient expansion at lower moisture content. In quality evaluation of the product, chemical composition of $30\%$ starch and $3\%$ salt added product was moisture $8.8\%$, lipid $2.4\%$, carbohydrate $46.7\%$, protein $36.1\%$, and ash $6.0\%$. Eleven membered panel test evaluated that fish-starch paste was acceptable in color, crisp-ness, taste, except a trace of fishy odour which could be masked by the addition of spice extracts.