• Transactions of the Korean Society of Mechanical Engineers
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• v.7 no.2
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• pp.226-232
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• 1983

회전수를 용접변수로 했을 때 이종강봉 및 이종강관의 마찰용접에 있어서 소성변형중에 발생한 AE(acoustic emission)량과 용접후의 냉각중에 발생한 AE량의 총량을 측정해석하고, 용접표면상 에 0.635mmR의 반원 노치를 가공했을 때의 용접부 인장강도를 구하여, AE총량과 용접부강도와 의 상관관계실험식 모델을 만들었고, 이들과 관계계산식과의 비교 조사와 95%신뢰성을 검증하였 고, 이종강의 마찰용접 중에 용접강도와 품질을 검토관리할 수 있는 기본자료가 되게 하였다.

• Journal of the Korean Society for Nondestructive Testing
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• v.15 no.4
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• pp.511-519
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• 1996

The purposes of this study are 1) to develop optimum FRW technique of SNCM220, SCM435, SACM645 and SCM415 bar-to-bar similar friction welding, 2) to develop in-process real-time weld quality nondestructive evaluation technique by acoustic emission method, and 3) to certify of weld quality by inspection of tensile fracture surface on friction welded joints.

• Journal of Industrial Technology
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• v.20 no.A
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• pp.57-62
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• 2000

This experiment was done to investigate the leaching and adsorption properties of heavy metals on porphyry. The comparison with respect to the leachability of heavy metals from porphyry between the Korea Standard Leaching Test (KSLT) and the Toxicity Characteristic Leaching Procedure (TCLP) was carried out. The fractional composition of leachate and the total concentration of heavy metal of porphyry were studied through Sequential Extraction Procedure (SEP) and EPA Method 3050. Adsorption experiment of porphyry has pointed out that the optimum dosage of porphyry for 50ppm Pb was over 10g/L, the effective particle size for absorption was below 200 mesh and the optimum pH was about 7. From the Freundlich' adsorption equation, 1/n was 1.0722, and k was 0.0041. After adsorption, the fractional composition of Pb was changed. The exchangeable, carbonate, reducible fractions were increased, and the organic fraction was not changed, and the residual fraction was decreased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.227-234
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• 1985

The present study was carried out for making clear the organic acids composition of some shellfishes and their boiled-dried products. Three species of shellfish such as top shell, hard clam and abalone were chosen as the experimental samples and analysed for their nonvolatile organic acids composition by gas liquid chromatography (GLC). Eight kinds of nonvolatile organic acid were identified in raw and boiled-dried top shell, major ones were succinic, malic and pyroglutamic acid. Out of nine kinds of nonvolatile acid was determined in raw and boiled-dried of hard clam, abundant ones were succinic, lactic and malic acid, And seven kinds of nonvolatile organic acid were detected in boiled-dried abalone while eight kinds in raw sample, abundant ones were succinic, lactic and pyroglutamic acid, respectively. In all samples, the total amount of nonvolatile organic acid was the most abundant in hard clam while the least in abalone, and the content of succinic acid was appeared as the most abundant one. In dried samples, the total amount of the nonvolatile organic acid was determined to be about half-decrease after the boiled-dried treatment of the raw samples, of which abalone showed the highest decreasing을 rate whereas hard clam was the lowest. In general, the decreasing rate of each acid was the higher in fumaric, malic and citric acid than in maleic, oxalic and succinic acid.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.784-788
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• 2001

Reliable data on the exposure of capsaicin, which evokes hot sensation in hot red pepper, are important prerequisites for studying biological functions of capsaicin in human body since its roles are controversial according to animal and epidemiological studies. To get accurate data, the use of urinary biomarkers was considered as a measure of internal exposure of capsaicin. After 2-day-capsaicin depletion five to six women in their 20's were instructed to eat 60 or 80 g/day hot red pepper soybean paste as a capsaicin source with meal which did not contain capsaicinoid, and to collect their urine separately. HPLC conditions were set to detect capsaicinoid and urinary metabolites at the same time. Most of capsaicinoid were excreted in the form of 4-hydroxy-3-methoxybenzoic acid in three subjects at the highest dose. This result suggests the oxidation of the 4-hydroxy3-methoxybenzaldehyde, the hydrolysis product of capsaicin, is the major metabolic pathway in the human body, whereas the reduction of the aldehyde is the major route in rats. However, neither any metabolite nor the parent compound was ever shown in two of the subjects reflecting large individual differences of capsaicin absorption and/or biotransformation.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.437-438
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• 2004

원자력시설의 정상운영시 방사성물질이 기체 및 액체상의 형태로 소외로 배출되며, 일정기간별로 배출된 핵종별 총량을 이용하여 주민피폭선량 평가를 수행함으로써 규제요건의 준수 여부를 확인한다. 이러한 원자력시설 주변 주민피폭선량평가에 적용되고 있는 주요 입력자료인 음식물섭취자료 등은 1988년 원자력연구소의 현장조사, 실험, 문헌조사 등을 통하여 결정되었으나 시간이 지남에 따라 일부자료의 경우 최신경향을 반영할 수 있도록 개정이 요구된다.(중략)

• Weed & Turfgrass Science
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• v.2 no.4
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• pp.381-386
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• 2013

Recent climatic changes by global warming include increased amount and intensity of rainfall. This study was conducted to find out possible roles of turfgrasses to reduce the impact of climatic changes, especially surface soil erosion. Soil erosions by intensive rain were measured after each significant precipitation from the artificially sloped plots of zoysiagrass, cool-season grass mixture of Kentucky bluegrass and perennial ryegrass and other typical korean summer crops. Sodded zoysiagrass resulted in minimal annual soil erosion followed by strip-sodded zoysiagrass and cool-season turfgrass mixture while dry-field rice and bean cultivations eroded the surface soils of 5 to 10 MT $ha^{-1}yr^{-1}$ and pepper cultivation resulted in 7 to 14 MT $ha^{-1}yr^{-1}$ annual loss of surface soil. Annual loss of surface soil from bare land with hand weeding was up to 18 MT $ha^{-1}yr^{-1}$ while greatly reduced soil erosion was observed from weed grown treatment.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.401-408
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• 2007

This study examined the histochemical and physiological characteristics during Korean native Ogol chickens (KNOC) development. The body weight, Pectoralis major and soleus muscle weights, and muscle samples were taken at hatching as well as at 3, 5, and 15 weeks of age. The fiber characteristics of the Pectoralis major and soleus muscles from the KNOC at hatching to 15 weeks of age were determined, and the deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein concentrations were measured from the left Pectoralis major muscles. A greater increase in body and muscle weights was detected between hatching and 3 weeks of age than during any other period. Moreover, the cross sectional area (CSA) of the fibers, as well as the total concentration of DNA, RNA, and protein also showed a greater increase betweenhatching and 3 weeks of age than during any other period. The KNOC breed is a dual purpose breed, however, the it has lower body and muscle weights than commercial meat type chickens or layer type chickens. Moreover, the KNOC breed has a small muscle fiber CSA of and a low nucleic acid concentration.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.289-294
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• 1997

우라늄 염화물의 생성을 위한 U$_3$O$_{8}$ 분말의 염화반응에 대한 열역학적 해석을 수행하여 실험조건을 도출하였고 이를 실험적으로 확인하였다. U$_3$O$_{8}$ 분말의 탄소, 염소와의 염화반응은 비가역 발열반응으로서 아르곤 기체분위기에서는 옥시염화물의 생성이 억제된 우라늄 염화물들을 생성할 수 있었다. 염화반응 적정온도 범위는 863～1065k로서 이 온도범위에서의 반응종결시간은 U$_3$O$_{8}$ 분말 60g을 기준으로 약 4시간 이내였고, 반응온도가 높을수록 반응속도가 빠르게 나타났다. 우라늄 염화물의 비휘발 회수율은 생성된 우라늄 염화물 총량의 30% 이내로 낮게 나타났다.

• Journal of Soil and Groundwater Environment
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• v.8 no.3
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• pp.61-73
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• 2003

A model describing the distribution of contaminants in soil/water systems for the application of soil-washing technology using surfactant was developed. The model simulation was conducted for screening the best surfactant, evaluating the effect of water dose, and optimizing soil-washing methodology. Naphthalene, phenanthrene, and pyrene as target compounds and Triton X-l00, Tergitol NP-10, Igepal CA-720, and Brij 30 as surfactants were used in the model simulations. The washing efficiency was not greatly enhanced by increasing water dose with the same total surfactant dose. The approach of successive washings was more efficient than a single washing with the same amount of water and surfactant. Equal allotment of the amount of water and surfactant was the best condition for the successive washings. The model can be applied for the optimal design of the soil washing process without extra experimental efforts.