• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.6
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• pp.576-585
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• 1991

General procedures of seed preparation as conventional guide had been established in China before most of Korean literature documented them. ‘Chwijongbeob’ (method of seed select) was to select good quality of seeds and to discard the rest. In ‘Seonjongbeob’ (method of seed grading) although China employed only ‘Sooseonbeob’ (method of seed select with water), but seeds were selected in order of selection of seeds by winds, selection of seeds by sieve and selection of seed with water in Korea. As compared with the recent techniques, those methods were perfect techniques for selection of good quality seeds of rice, except for method of seed selection by salt water was developed. The method for measurement of seed moisture, and for measurement of melted snow, spoiled urine and extracted juice by boiling water with the bone of livestock were originated from ancient China. The farming books in Korea were more or less followed the above methods. However, these techniques were complicated and impractical interms of validity and rationality. Also, it is judged that these tchniques are more appropriate in dry areas and alkaline soil of China rather than in Korean conditions. The plowing is a work to begin farming, and is operated for air ventilation between atmosphere and earth. Also, this techniques was adopted in the farming books from the early to the late Chosun dynasty without changes. Fields were deep-plowed in the first, in fall (or in spring) and for cultivation, and were shallow -plowed in the second, in spring (or in summer) and in intertillage. The former was for water reserve and land preparation, and the later was for weed control with intertillage. However, plowing in fall which was different from fallowing in dry areas, was recommended in Korea (Jikseol). but was not practiced in Sejongsilrok. This was changed with time, and plowing for cultivation in Korea was interrelated with use of green manure crops, method of plowing of upseting plough, method of manure practice and sometimes dry plowing. In addition, until the 15th century method of using a kind of plowing-tool made of log as farm tools was created to support reclamation for enlargement of farm land in mountaineous and coastal areas. For desolate farm lands by many internal and external disturbances, one tried to recover yield ability by increasing labor productivity from the 17th or 18th century. To do this, ‘Banjongbeob’ (culture method by upset plowing weed control) and ‘Hwanubeob’(culture method by firing weed control) which were cultural methods of ancient China were readapoted but the results were not clearly informed. Also, the reality of those was reexamined in the end of the Chosun dynasty.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.3
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• pp.172-180
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• 2003

The purpose of this study is to observe the heat transfer process in in-vivo human muscle based on Proton Resonance Frequency(PRF) method in Magnetic Resonance Imaging(MRI). MRI was obtained to measure the temperature variation according to the heat transfer in phantom and in-vivo human calf muscle. A phantom(2% agarose gel) was used in this experiment. MR temperature measurement was compared with the direct temperature measurement using a T-type thermocouple. After heating agarose gel to more than 5$0^{\circ}C$ in boiling hot water, raw data were acquired every 3 minutes during one hour cooling period for a phantom case. For human study heat was forced to deliver into volunteer's calf muscle using hot pack. Reference data were once acquired before a hot pack emits heat and raw data were acquired every 2 minutes during 30minutes. Acquired raw data were reconstructed to phase-difference images with reference image to observe the temperature change. Phase-difference of the phantom was linearly proportional to the temperature change in the range of 34.2$^{\circ}C$ and 50.2$^{\circ}C$. Temperature resolution was 0.0457 radian /$^{\circ}C$(0.0038 ppm/$^{\circ}C$) in phantom case. In vivo-case, mean phase-difference in near region from the hot pack is smaller than that in far region. Different temperature distribution was observed in proportion to a distance from heat source.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.2
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• pp.234-241
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• 2015

This study investigated the effects of different cooking methods on contents of cholesterol, retinol, and tocopherol in poultry meats (chicken, Korean native chicken, and duck) using saponification extraction and HPLC analysis. The cooking methods were boiling, grilling, stir-frying, deep-frying, steaming, roasting, and microwaving. Generally, contents of cholesterol increased after cooking. Especially, after deep-frying, large amounts of cholesterol were detected from legs of chicken (94.25 mg/100 g) and wings of Korean native chicken (132.96 mg/100 g). High cholesterol content was detected in wings (233.77 mg/100 g) from duck after microwaving. However, contents of retinol decreased after cooking. The retinol contents of breast meat from Korean native chicken were low ($0.86{\sim}0.56{\mu}g/100g$) compared to other meats ($1.10{\sim}22.66{\mu}g/100g$ in chicken and $1.96{\sim}36.80{\mu}g/100g$ in duck), whereas raw materials from wings of all poultry showed the highest tocopherol contents. Of the various cooking methods, stir-frying and deep-frying resulted in increased ${\alpha}$-tocopherol contents in meats.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.292-301
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• 1997

In drying process, to minimize the quality degradation by improved drying process and pretreatment methods, carrots, cabbages and radishes were dried and rehydrated. Physico-chemical properties of product were analyzed to determine the optimum pretreatment method and drying models were applied to explain drying mechanisms. Microwave, steam and water were used prior to drying as blanching method. In consideration of physical properties, optimum treatment time was decided that microwave was 1 min, steam and water were each 10 min. Control, steam, water, microwave and osmotic dehydration were treated prior to drying as pretreatment individually, osmotic dehydration was lower than the other treatmemt in drying efficiency, but carotene content was higher than the others. The effect continued after rehydration. Ten panelists tested dried and rehydrated carrots. After rehydration, the quality of air dried product with osmotic dehydration was superior to freeze dried without treatment. The fittness of drying models were conducted in order to explain the mechanism of drying each process. Quadratic model was most fittable to explain during drying. However, in rehydration process, no fittable model was found.

• Journal of the Korean Ceramic Society
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• v.41 no.10 s.269
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• pp.742-748
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• 2004

Isopropanol of low boiling point was used as a solvent to prepare Al-doped ZnO(AZO) thin films. A homogeneous and stable sol was made from Zn acetate a solute whose mole concentration was 0.7mol/$\iota$ and Al chloride as a dopant. Al-doped ZnO thin films were prepared by sol-gel method as a function of post-heating temperature from 500 to $700^{\circ}C$ and the optical and electrical properties were investigated. The c-axis orientation along (002) plane was enhanced with the increasing of post-heating temperature and the surface morphology of the films showed a homogeneous and nano-sized microstructure. The optical transmittance of the films post-heated below $650^{\circ}C$ was over $86\%$, but decreased at $700^{\circ}C$. The electrical resistivity of the thin films decreased from 73 to 22 $\Omega$-cm as the post-heating temperature increased up to $650^{\circ}C$, but increased greatly to 580 $\Omega$-cm at $700^{\circ}C$. XPS analysis indicated that the deterioration of electrical and optical properties was attributed to the precipitation of $Al_2O_3$ phase on the surface of AZO thin film. This result suggests that the optimum post-heating temperature to improve electrical and optical properties is $600^{\circ}C$.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.11-18
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• 2000

This study was conducted to establish an efficient screening method of membrane-disrupting herbicides, based on the result that membrane leakage leading to evolution of carbonyl compounds and aldehydes could be colorimetrically assessed by formation of stable chromophores with MBTH and ferric chloride. Assay conditions including plant material, light intensity, irradiation time, concentrations of reagents for colorization, and reaction time were optimized, and activities of different types of known herbicides were investigated with cucumber cotyledon discs. That result indicated that this assay was sensitive to membrane-disrupting herbicides, such as protoporphyrinogen oxidase inhibitors (acifluorfen, oxyfluorfen, oxadiazon) and an electron interceptor from photosystem I(paraquat). With seven compounds newly synthesized, highly positive correlation was observed between herbicidal activities measured by greenhouse bioassay and MBTH method. Because only a single disc(4 mm diameter) from cucumber cotyledon in 60 ${\mu}L$ of incubation solution was required to assay, a large number of herbicides could be tested simultaneously using 96-well microtitre plates. But the assay efficiency is not likely to significantly increase because of the boiling step during the reaction.

• Journal of Environmental Health Sciences
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• v.5 no.1
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• pp.10-17
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• 1978

Recently this writer has conducted a comprehensive survey of 38 private businesses where group feeding is practiced, with a view to determining the condition of nutrition intake by the blue collar workers of these businesses firms as well as gaining an indication of their facilities management along with their sanitary precautions. The survey has revealed, among others, a number of interesting data such as shown below. 1. There are a total of 1,054 workers being fed in groups daily at each of the above business companies, with only one nutrition specialist regardless of the number of workers to be fed or the number of times they are fed daily. The average number of cooks comes to 2.7 persons per 100 workers, while 42.2% of the companies provide four meals a day including mid-night supper, with the result that the workers are fed 3.13 times a day on an average. 2. The average feeding cost amounts to 151 won per meal per person, of which 86 won is payed by the workers themselves and 115 won by the companies involved. 3. The average fbod intake has been found to be 490 grams which can be further broken down into 44grams of animal food and 446grams of vegetable food. These figures are higher than those revealed by the 1975 investigation of the nation's average nutrition intake. 4. The survey also shows the daily calorie consumption per person to be as high as 896 calories including 37 grams of protein which is further broken down into 11 grams of animal protein and 26grams of vegetable protein. With respect to other types of nutrients excepting Vitamin-A, the companies concerned are believed to prorids more than what the survey of the nation's nutrition has revealed or the amount recommended by Korea FAO assoc!ation as desirable. 5. As for facilities management, there is still much room for future improvement. Some 97.4% of the companies surveyed are not equipped with the steam table, which indicates lack of concern along this line as well as a very how degree of equipment utilizations. Distribution of the food in the dining room is generally depedent on self-service method. 6. Speaking of sanitary precautions taken by those businesses involved, some 76.3% are found to have their compounds haunted by rats and other insects. Some 73.7% of them are dependent on boiling method for disinfection of kitchen utensils, which is conducted by 50% of those industries only two or three times a week. It seems hardly feasible to conduct disinfection everyday.

• Archives of Plastic Surgery
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• v.41 no.4
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• pp.317-324
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• 2014

Background Burn infliction techniques are poorly described in rat models. An accurate study can only be achieved with wounds that are uniform in size and depth. We describe a simple reproducible method for creating consistent burn wounds in rats. Methods Ten male Sprague-Dawley rats were anesthetized and dorsum shaved. A 100 g cylindrical stainless-steel rod (1 cm diameter) was heated to $100^{\circ}C$ in boiling water. Temperature was monitored using a thermocouple. We performed two consecutive toe-pinch tests on different limbs to assess the depth of sedation. Burn infliction was limited to the loin. The skin was pulled upwards, away from the underlying viscera, creating a flat surface. The rod rested on its own weight for 5, 10, and 20 seconds at three different sites on each rat. Wounds were evaluated for size, morphology and depth. Results Average wound size was $0.9957cm^2$ (standard deviation [SD] 0.1845) (n=30). Wounds created with duration of 5 seconds were pale, with an indistinct margin of erythema. Wounds of 10 and 20 seconds were well-defined, uniformly brown with a rim of erythema. Average depths of tissue damage were 1.30 mm (SD 0.424), 2.35 mm (SD 0.071), and 2.60 mm (SD 0.283) for duration of 5, 10, 20 seconds respectively. Burn duration of 5 seconds resulted in full-thickness damage. Burn duration of 10 seconds and 20 seconds resulted in full-thickness damage, involving subjacent skeletal muscle. Conclusions This is a simple reproducible method for creating burn wounds consistent in size and depth in a rat burn model.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.25-30
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• 1997

Volatile components of green tea were isolated by purge and trap headspace method and were analyzed by GC and GC/MSD. And ten headspace volatiles were compared with volatiles isolated by simultaneous distillation-extraction(SDE) method. A total of 99 components were identified in the green tea volatile components, from which 88 components were identified in the headspace volatiles, contained 20 alcohols, 30 hydrocarbons, 21 aldehydes, 10 ketones, 2 acids and 5 miscellaneous components. The major components were low boiling components, such as methyl butanal(3.1%), 1-penten-3-ol(5.48%), 2-penten-1-ol(2.89%), hexanal(5.77%), heptanal(1.90%), and ere 2,4-eptadienal(4.28%), linalool(2.27%), 2,6-dimethyl cyclohexanol(2.57%), $\alpha$-pinene(1.52%), caryophyllene(1.70%), and carbonyl compounds, such as $\alpha$-ionone(2.62%), $\beta$-ionone(2.98%), $\beta$-cyclocitral(2.0%). On the other hand SDE volatiles, from which 64 components were identified, contained 16 alcohols, 16 ydrocarbons, 15 aldehydes, 10 ketones, 3 acids and 4 miscellaneous components. The major components were alcohols, such as, benzyl alcohol(3.79%), linalool(9.52%), terpineol(2.16%), geraniol(2.75%), nerolidol(6.50%), ketones, such as $\alpha$-ionone(1.77%), $\beta$-ionone(4.80%), geranyl acetone(1.82%) and acids, such as hexanoic acid(1.45%), nonanoic acid(1.11%).

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1033-1044
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• 2015

During the Joseon period, kimchi was mostly made by heating the ingredients. Since salt was pricey at the time, in order to save salt and time, people used a method that involved destroying the cell wall by heating the vegetables. However, this method is no longer passed down. Thus, in this paper, we re-discovered how kimchi was made through heating while analyzing the recipes for kimchi during the Joseon period. There were 27 kinds of kimchi made through blanching. To keep the vegetables from becoming soggy, 2 kinds of kimchi were made by putting the ingredients in potassium aluminum sulfate water and 3 kinds were made through blanching the ingredients in limewater. There were 7 kinds of kimchi made by heating in vinegar, 5 kinds by boiling the ingredients, 6 kinds by stir-frying the ingredients, 2 kinds by stir-frying the ingredients with salt, and 3 kinds by steaming the ingredients. In order to eradicate unwanted germs, leaving only Lactobacillus, 25 kinds of kimchi were made by draining the boiled mixture. A total of 17 kinds of kimchi were made by heating the kimchi pot with compost including that of horses. For elders with weak teeth and poor digestion, 7 kinds of kimchi were made after heating, including 3 kinds of sukkkakdugi (cubed radish kimchi made with boiled radish). 3 kinds of chaekimchi (julienned kimchi) and 3 kinds of chaekkakdugi (kimchi with julienned radish) for elders existed as well.