• Korean Journal of Ecology and Environment
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• v.50 no.3
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• pp.275-285
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• 2017

To investigate the changes of dominant species of benthic macroinvertebrates according to the changes of temperature and precipitation, we surveyed twenty sites of the main Seomjin River in May and September in 2013 and 2014. The temperature, precipitation, water quality factors and substrate composition, which are important factors in benthos habitat environment, were collected and measured. The average temperature of the Seomjin River increased by $0.2^{\circ}C$ in 2014 compared to 2013, and the temperature increased from upstream to downstream, showing a difference of more than $3^{\circ}C$. Also, the annual cumulative precipitation (ACP) was increased toward low latitude. The temperature of Seomjin River increased more than twice in September ($21.7{\sim}24.5^{\circ}C$) after rainfall compared to May ($7.6{\sim}11.3^{\circ}C$) before rainfall, and CP (cumulative precipitation) increased about 3 times before rainfall (263 mm~287.5 mm) and after rainfall (756.3 mm~882 mm). Due to washing effect by summer precipitation, total number of species and individuals for benthic macroinvertebrates were higher in May than in September. Chironomidae sp. and Choroterpes altioculus were dominated in May, Ecdyonurus levis, Macrostemum radiatum and Choroterpes altioculus were dominated in September. As a result of correlation analysis between community indices and environment factors, it was found that there is a high correlation with boulder and sand among substrate compositions. According to the results of cluster analysis based on temperature, CP and the dominant species of benthic macroinvertebrates in Seomjin River, it was divided into two groups following temperature and CP, and the dominant species and geographical position were reflected and divided into detailed groups.

• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.63-75
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• 2007

A survey on sanitary management at 98 food service institutions located in Jeollabuk-Do were conducted. Food service institutions included 13 hospitals, 38 schools, 40 enterprises, and 7 others. The sterilization in boiling water was used for disinfection of tableware, spoon and chopsticks, and dish towel. Cooking kit, refrigerator, chopping board, and knife were sterilized with disinfectant. Frequency of sanitary training program on employees was 56.1% for 1 time/month, 12.2% for 2-3 times/month, and 11.3% for 1 time/week. Preparing ratio of defrosting, warehouse and rest room, and washing and sterilization diary were 73.8, 60.5, and 54.5%, respectively. However, checking ratio of environments (9.5%), personal sanitation (10.8%), and sanitary training program diary(8.4%) were low. Major obstacle factors on the introduction of Hazard analysis critical control point (HACCP) system into food service institutions were lack of equipment and facilities (54.1%) and lack of understanding and data on HACCP system (17.3%). Therefore, in order to reduce the outbreak of food-borne diseases increasing frequency, we estimated that the introduction of sanitary management system and the conversion of dietician' perception on sanitary managements in food service institutions were needed.

• Food Science of Animal Resources
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• v.26 no.2
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• pp.204-211
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• 2006

This study investigated the effect of salt and glucono-${\delta}$-lactone (GdL) on the cold-set binding of restructured pork washed and pressurized at 200 MPa. Binding strength, PH, water holding capacity (WHC) and color were determined. NaCl improved pH, WHC and binding strength. GdL also increased binding strength while decreased WHC and pH significantly (p<0.05). However, low GdL level combined with NaCl showed high pH and WHC, compared to control. In color, NaCl decreased $L^*$-value with increasing $a^*$-value significantly (p<0.05). In contrast to NaCl, GdL increased $L^*$-value and decreased $a^*$-value. GdL tended to decrease $b^*$-value and significant differences were found when GdL was added above 1%. Pearson's correlation coefficients presented that NaCl had a significant effect on binding strength (0.6632) and lightness (-0.7330) while GdL had a significant correlation with all parameters barring binding strength. The results indicated that under washing and pressure treatments, GdL had a potential effect on cold-set binding with reducing NaCl concentration, especially when low GdL concentration combined with NaCl was added.

• Journal of Conservation Science
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• v.28 no.1
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• pp.21-27
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• 2012

In the Chosun period, the noble class usually buried the dead bodies in the lime-covered tomb. Recently their costumes are excavated while maintaining the shape. However, the textiles discovered from the inside have been degradated by a body and moisture. To conserve these textiles one of the most important thing is how to clean these textiles right after the excavation. The purpose of this study is to examine the effects of wet cleaning to minimize the color change of textile remains. For this purpose, silk and cotton were dyed with natural dyes (7 red, 1 blue, 6 yellow, 4 green and 4 purple colors), then they were kept for 6 months with pork meat at $10^{\circ}C$, and were washed by four cleaning solutions (water, anionic surfactant (SDS), non-ionic surfactant (Triton X-100) and natural surfactant (saponin)) at $20^{\circ}C$ and $40^{\circ}C$. The color change was evaluated by color difference (${\Delta}E$) between non-treated and after washed samples. From the results, it was found that the color changes are significantly different depending on the washing temperature, textile material, the cleaning agents and the type of dyes.

• Microbiology and Biotechnology Letters
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• v.5 no.1
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• pp.18-23
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• 1977

Experiments were carried out to pursue the availability and the feasibility of utilizable cellulosic materials as substrate for the production of cellulosic single cell protein. The resuluts were obtained as fellows. 1. Effects of carbolydrates as a sole carton source on the growth of Cellulomonas flavigena KIST 321 were examined. The result showed that cellulose and xylose would be most utlizable for cell mass production. 2. Alkaline treated waste papers and clothes resulted in good growth of the organism than intact ones did. However the waste papers as substrate of cellulosic fermentation were not digestible, even if the meterial was treated with alkalies. 3. Rice straw, rape straw and panic grass appeared to be good substrates for the cell mass production. 4. Leaves were proved to be a good substrate for the cell mass production, but wood sawdust was hardly digested by merely alkaline treatment. 5. When cellulosic wastes as the substrate were examined into the concentration of alkaline solution, the result suggested that the best productivity of cell mass from cellulosic materials was obtained on treatment with 0.8∼1.0％ NaOH solution. 6. The productivity of cell mass was increased by washing out with water after alkaline treatment of newspaper, pine sawdust, lime sawdust and pine leaf.

• Journal of Korean Academy of Nursing
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• v.23 no.3
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• pp.377-398
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• 1993

A survey of infant practices was conducted to provide information on which to base planned nursing interventions. The subjects were a convenience sample of 168 mothers visiting out - patients departments of five general hospitals and one public health center in Seoul for immunizations or treatment for common colds for their infants from two to 12 months of age. Data collection was carried out from July 8th to September 30th, 1991 using a questionnaire of 84 questions, 31 on the type of feeding, 22 on supplementary feeding and 21 on demographic infer mation. The results are summarized as follows : 1) The type of feeding was primarily artificial feed-ing (63.1%), followed by mixed feeding (22%) and breast feeding (14.9%) of the 59 mothers expecting during pregnancy to breast feed, 54. 2% changed artificial feeding and 30.5% went on to breast feed as they had expected. For mothers expecting to continue breast feeding over seven months. only one infant was being breast fed for over seven months. 2) For the 106 mothers using artificial feeding, 70. 8% hed attempted breast feeding, 64% of them for less than a month. Breast milk had been suppressed by for medication (38.7%) : 34.9% had used no specia] means. 3) The major reasons for replacing breast feeding with artificial feeding were the infants' demand for more milk (47.2% ) and insufficient supply of breast milk (49.3％). 4) Most mixed feeding was started at the age of one to three months (59.5%). Only 34.4% gave an artificial feeding after breast feeding : most (46%) alternated breast feeding with artificial feeding. On the whole, the motive for mixed feeding was the lack of breast milk (70.3%). 5) Many mothers (81.8%) were adding vitamin or mineral supplements to artificial milk and 51.5% were adding something to faciliate digestion. As for the method of sterilizing milk bottles and nipples, 56% had sterilized them together in boiling water from the beginning : 27% were just washing the bottles after boiling only once initially when measuring artificial milk powder, 31. 5% of the mothers over filled the measuring spoon rather than to the level. 6) The mother's occupation was related to her way of feeding. Mothers at home full time did more breast feeding than mothers employed outside the home. (x²=5.72, p=〈0.05). 7) Most mothers began supplementary food, from three to four months (48.8%) : 11.2% began later than seven months. Supplementary food was given between milk feedings by 67.2% of the mothers : 19.2% gave it before a milk feeding. Some mothers(26.4%) made their own supplementary food : 19.2% used ready - made supplementary food products for convenience. Recommendations for nursing interventions included : 1. Prenatal education about the advantages of breast feeding and breast care, and home visits after delivery for counselling related to breast feeding. Correct preparation of artificial feeding methods need to be taught in both pre & postnatal periods. In addition, specific education about supplementary feeding needed. 2. Further research is indicated about the Perceived lack of supply of breast milk and about the effectiveness of nursing interventions to Promote breast feeding.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.3
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• pp.300-306
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• 1989

This study was investigated to determine the functional properties of mugbean protein isolates(MPI) from sunhwa-nogdu(SH) and conventional mungbean varieties(C). MPI were prepared from defatted mungbean flour by extraction with 0.1N NaOH, precipitation at pH 4.5, washing of dispersed precipitate with buffer solution and distilled water, and subsequent freeze-drying. Crude protein content of MPI was in the range of $88.7{\sim}91.3%$. The lowest solubility was recorded at $pH\;4{\sim}5$, whereas the best buffering action was in the range of $5.5{\sim}7.5$. On the other hand, gelation of MPI was found to depend on the protein concentration. In the cases of foamability, % volume increase and specific volume were higher for 10 min. with a good whipping ability. And also, the MPI properties of two varieties of SH and C were compared and discussed.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.310-316
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• 2012

The chromaticity of polyethylene glycol (PEG) generated from the recyling of a silicone slurry waste was improved by using activated carbon powder and a carbon filter. The color change of the PEG waste was investigated by changing the amount of adsorbent, adsorption time and temperature. The surface area of activated carbon did not have a significant impact on improving the color of the PEG waste. According to the results for the APHA color variation of the PEG waste changing the amount of the carbon adsorbent, the optimal usage to achieve the low APHA value was 100~150 mg-C/g-PEG. From the investigatnion on the effect of the adsorption temperature range from $25^{\circ}C$ to $100^{\circ}C$, it was found that the optimal temperatures were $40{\sim}50^{\circ}C$ in terms of achieving the lowest APHA value. The variation of the APHA color was investigated by changing the operation condition of the activated carbon filters. The use of ACF was a good way to enhance the chromaticity of the PEG waste. As a result, the APHA value of the PEG waste (APHA=53 at the initial waste) was reduced to be 10 through the ACF purification. It was also confirmed that the performance of the used carbon adsorbent can be recovered by the washing with purified water.

• Clean Technology
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• v.18 no.1
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• pp.63-68
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• 2012

In this study, aluminum hydroxide ($Al(OH)_3$) was synthesized by Bayer process and sodium contained in $Al(OH)_3$ was removed with the acid solution such as HCl and acetic acid for the synthesis of high purity alumina. The bauxite produced in Queensland of Australia was used for the production of alumina by Bayer, and was crushed to a particle size of below 10 um by attrition mill. The crushed bauxite was treated in sodium hydroxide solution of 5 N for the elution of aluminum component. The elution of aluminum from bauxite was carried out at $140^{\circ}C$ and 3.4 atm in autoclave. The sample solution was separated to the red mud and liquid solution by filter paper. The elution of aluminum from bauxite was confirmed with changing a structure and aluminum content in both bauxite and red mud analyzed by XRD and EDX. Aluminum contained in the separated solution was crystallized to $Al(OH)_3$ with the addition of aluminum hydroxide used as the seed material. $Al(OH)_3$ powder obtained during the crystallization process was purified by several times washing with distillated water. It was also confirmed that the sodium remained in $Al(OH)_3$ powder is removed with acid solution. The purity of $Al(OH)_3$ powder produced in this study was 99.3% and the content of sodium was reduced to approximately 0.009% after the acid treatment.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.1
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• pp.103-115
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• 1998

Adhesion of composite resin to tooth structure has been of tremendous signgicance in clinical dentistry. Due to the lack of adhesion between composite restorative resins and enamel and dentin, microleakage occurs at the tooth/restoration interface. This may lead to discoloration, secondary caries, marginal breakdown, postoperative sensitivity, and even pulpal pathology. According to extensive use of composite resin, every effort on improving bonding strength and reducing microleakage between a tooth and composite resin has been continued. This study was conducted to determine the difference in microleakage in enamel and dentin treated with air-abrasion, acid etching and combination when restored with composite resin. Class V cavities were prepared on 30 premolars. The specimens were divided into following groups. group 1:air-abrasion+Scotchbond Multi-purpose group 4 :air-abrasion+All-Bond 2 group 2:acid etching+Scotchbond Multi-purpose group 5 :acid etching+All-Bond 2 group 3:combination+Scotchbond Multi-purpose group 6 :combination+All-Bond 2 #combination:air-abrasion + acid etching The specimens were filled with Z-100 after application of Scotchbond Multi-purpose and All-Bond 2. Thermocycling was conducted by alternately dipping the specimens in $5^{\circ}C$ and $55^{\circ}C$ water for 30 seconds 500 times. 1% methylene blue was applied and the specimens were left for 24 hours at $37^{\circ}C$. After washing out the dye, the tooth was sectioned buccolingually along the axis. The sectioned surface was observed with stereoscope for dye penetration. The author has measured the microleakage in teeth prepared with air-abrasion, acid ethching and combination to study the difference in microleakage following different methods of tooth surface treatment and has come to following results. 1. In comparing microleakage between groups, group 1 and 4 showed statistically significant difference from group 2, 3, 5 and 6(p<0.05). There was no significant difference among group 2, 3, 5, 6(p>0.05) nor between group 1 and 4(p>0.05). 2. In comparing microleakage among tooth surface treatment methods, Air-abrasion group showed significantly more microleakage than acid etching group and combination(airabrasion + acid etching) group(p<0.05). Combination(acid etching+air-abrasion)group tended to show lesser microleakage than acid etching group, but this was not statistically significant(p>0.05). 3. In comparing microleakage between bonding agents, there was no statistically significant difference between Scotch bond Multi-purpose and All-Bond 2(p>0.05).