• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.1
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• pp.72-80
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• 2005

A recycled aggregate contains impurities that affect negative effects on physical properties of concrete. Therefore, a test method for examining impurities content in recycled aggregate is necessary before use of recycled aggregate. In this study, the test method by visual examination for separating impurities in recycled fine and coarse aggregates was developed. The results of the test are as follow: 1. The current KS F 2576 was necessary for comprehensive revision including types of tested recycled aggregate, definition of terminology, quantity of sample, and test method. 2. Visual examination is appropriate for larger than impurity panicle size of 1.2mm, and the larger panicle size the shorter time was required. 3. For the impurity content test by visual examination, the easiness and accuracy of the test can be obtained from the condition of sample weight of 30 grams with particle size of 2.5mm to 5mm for recycled fine aggregate and the condition of sample weight of 1 kilogram with panicle size of larger than 5mm for recycled coarse aggregate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.17-22
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• 1977

In the present paper, the effect of sodium sulfite treatment on tile inhibition of browning reactions occurring in the storage of dried oyster was tested and the supplementary effect of antioxidantsaddedwasalsomentioned. Dried oysters treated with sodium sulfite solutions as described in the previous paper(Lee and Choi, 1977) were stored in the bottles with silica gel bags at room temperature with or without the application of antioxidants. The ethanol solution of an antioxidant mixture(BHA, BHT, plus, synergists) was sprayed on the surface of cooked oyster before drying. The density of brown pigment was determined spectrophotometrically by measuring the absorbance at 420 and 440 nm of both fractions of pigment extract, namely chloroform-methanol and water soluble fractions, which represent the brown color developed by fat oxidation and Maillard reactions respectively. TBA value was also measured for the oxidative rancidity in oysters during the storage. It appeared from the results that the 0.5 M sodium sulfite-60minute treated samples showed better effect after 150 day storage at room temperature. Controlling tile pH of treating solutions, did not reveal so much different in inhibitory effect in the aspect of color but a more reduction of tyrosine and reducing sugar was resulted with acidic solution than with alkaline solution. The development of brown color in dried oyster seemed to be leaded rather by the oxidative rancidity of lipids than sugar-amino reactions particularly in a long-term storage since the browning of chloroform-methanol fraction progressed more rapidly than of water. soluble fraction. The application of antioxidant, therefore, could largely retard the browning of the product as appeared in the results that sodium sulfite treated oyster with addition of antioxidant kept the best color during the storage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.23-29
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• 1977

Three kinds of samples, Trachpenalus curiviostris, Astroconger myriaster and Cantherines modestus which were pre-treated in a processing plant were frozen at $-40^{\circ}C$ in a contact freezer and stored for 32 days.The numbers of general bacterium, coliforms and E. coli were measured at 8 day intevals during frozen storage and the isolated strains was classified. The results are as follows; 1. The numbers of coliforms and E. coli in the samples before freezing were much higher, than those during frozen storage and it tended to decrease. 2. General bacteria showed little change in number before and after being frozen. Among 97 strains of isolated coliforms, only 4 strains of K. aerogenes I ana 4 strains of K, cloacae were classified and the rest was not determined. 3. Ninety percent of coliforms was found to be psychrotrophic coliforms, which were able to grow at $5^{\circ}C$ within a week. 4. Vibrio and Pseudomonas were superior in number before freezing while Flavobacterium cytophaga and Moraxella were superior during frozem storage.

• Composites Research
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• v.31 no.5
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• pp.260-266
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• 2018

This study investigates thermal and mechanical characterization of Hafnium carbide coating on the $C_f-C$ composites. The hafnium carbide coatings by vacuum plasma spray on the C/C-SiC composites are prepared to evaluate oxidation and wear resistance. We perform the thermal durability tests by thermal cycling at $1200^{\circ}C$ for 10cycles in air and investigates the weight change of each cycle. We also evaluate the wear and indentation behavior using tungsten carbide ball indenter as a mechanical evaluation. As a result, the HfC coating is beneficial to reduce of weight loss during thermal cycling test and improve the elastic property of C/C-SiC composite. Especially, the HfC coating improves the wear resistance of C/C-SiC composite.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2000.05a
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• pp.5-7
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• 2000

국내에서의 식이섬유의 이용은 대부분 저분자량의 수용성 식이섬유를 이용한 음료형태가 주류를 이루고 있으며, 밀기울, 귀리, 옥수수 껍질 등으로 부터 얻는 불용성 식이섬유는 제과 및 제빵등에 이용되어 오고 있다. 수용성 식이섬유는 혈중 콜레스테롤을 저하시키며, 불용성 식이섬유는 변비예방과 장기능 증진효과가 탁월한 것으로 알려져 있다. 그러므로, 대장암과 변비같은 장질환 환자가 날로 증가하고 있는 상황에서 국내산 미이용 자원으로부터 불용성 식이섬유의 기능성 향상과 활용기술을 개발하는 것은 식품산업적 가치가 크다고 할 수 있다. 또한, 국내에서 소비되고 있는 폴리덱스트로스와 올리고당과 같은 기능성 당류의 대부분이 외국에서 수입하여 국내에 보급되고 있기 때문에 큰 외화지출이 되고 있다. 따라서 본고에서는 국내산 미곡 부산물인 밀기울 식이섬유 세포벽의 불용성 구조를 수용성으로 변화시킬 수 있는 변형기술과 얻어진 수용성 식이섬유 소재의 특성을 소개하고자 한다. 즉, 밀기울 세포벽의 수용화를 위한 가공처리는 압출성형 공정에 의하여 실시하였으며, 수용화가 수반되는 압출성형 조건에 따른 식이섬유 소재의 이화학적 특성과 수용화가 일어난 세포벽 성분의 분해기작에 대한 연구결과를 정리하였다. 그리고, 현행 올리고당과 식이섬유의 산업적 생산공정에서 문제점으로 대두되고 있는 효소처리, 산성하에서의 감압가열, 고점도 원료물질의 이송, 생물공학적 공정제어, 반응시간, 잔여 효소의 불활성화 및 재활용, 제조원가 상승 등과 같은 것을 해결하거나 개선할 수 있는 효율적인 압출반응공정의 조건과 생산된 소재 glucooligosaccharide, fructooligosaccharide, galactooligosaccharide 등의 특성에 대하여 논하여 보기로 한다.경우가 많지 않다. 또한 그 발생 경위나 원인요소에 대해서는 일반에게 공개되지 않고 있어, 우리가 실천하여 식중독을 예방할 수 있는 정보가 함께 제시되지 못하는 형편이다. 따라서 본 고에서는 최근 수년간 외국에서 학교급식을 비롯한 집단급식 등에서 발생한 식중독 사례를 중심으로 고찰, 분석하였다. 이로부터 식중독 발생에 기여한 주요 원인을 찾아내고 여기서 얻어지는 교훈을 토대로 식중독 발생을 예방 및 최소화할 수 있는 실천적 대처 방안을 모색해 보고자 한다.중의 E. coli O157:H7이 연관되어있다는 보고도 있다. 목장 방문시 원유를 마신 어린이에서 HUS가 유발하였고, 균분리 결과, 농장의 소와 어린이에서 유사한 E. coli O157:H7이 분리된 바 있다. 본 연자들은 베로톡신 유형, plasmid profiles, RFLP 분석, phage type을 기초로하여 소에서 분리된 E. coli O157:H7이 사람유래주와 매우 유사함을 확인하였다.mm 및 2-6mm 난포에서의 101개(67.8%) 및 47개(50.0%) 보다 매우 낮게 나타났다. 전체 회수 난포란수도 4등급이 59.1%(149/252)로써 1, 2, 3등급의 0.4% (1/252), 7.6%(19/252) 및 32.9%(83/252)보다 높게 나타났다. 1회 평균 회수 난포란은 $\leq$2mm 난포에서 4.8$\pm$3.7개로써 2-6mm(3.0$\pm$3.4개) 및 $\geq$6mm (0.3$\pm$0.6개)보다 높았으며, 1회당 평균 8.1$\pm$5.1개의 난포란을 회수하였다. investigation can be separated into sa

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.786-789
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• 1996

An image processing system was built to evaluate the color properties of apple and meat. The system consisted of video camera, video card, 32 bit microcomputer and an optical illuminator. The operating software was developed to carry out capturing, analyzing, displaying and storing of the 8 bit digitized images of food. The images of apples at various maturing stages were investigated to obtain the color histogram of R, G, B and Hunter value. RGB histogram showed a major difference in G value, 35.01, the minor change in R value, 6.16, and the negligible difference in B value. The image of beef cut was separated into two parts, fat and lean tissue, by applying threshold value method based on the digital value of color. The threshold value for fat was over 240 and for lean under 230 in R value, respectively. The resulting non fat image showed 2% decreased color difference value, ${\Delta}E$, than whole meat cut.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.730-735
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• 1993

This study was performed in order to clarify whether the creaming power of lard could be improved by random interesterification. The physicochemical properties, solid fat content, consistency, and creaming power of fat, and sensory evaluation on cream were investigated. The temperature of SFC $5{\sim}30$ showed the wider range from $10^{\circ}C\;to\;33^{\circ}C$ in random interesterified lard than that from $16^{\circ}C\;to\;30^{\circ}C$ in lard. The consistency of random interesterified lard was gradually decreased as temperature was increased, and was about $2000g\;per\;cm^{2}$ at low temperature level below $10^{\circ}C$. The sensory evaluation at maximum over ruu indicated that texture, polish and solubility of the cream made with random interesterified lard was slightly lower than that with lard, but random interesterified lard greatly improved the viscosity and firmness of cream. As the result of this study, the creaming power of lard was increased by random interesterification. Especially, the random interesterified lard could be considered as the better fat materials used in winter cream.

• The Journal of Society for e-Business Studies
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• v.23 no.1
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• pp.1-22
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• 2018

The value chain has been utilized as a strategic tool to improve competitive advantage, mainly at the enterprise level and at the industrial level. However, in order to conduct value chain analysis at the enterprise level, the client companies of the parent company should be classified according to whether they belong to it's value chain. The establishment of a value chain for a single company can be performed smoothly by experts, but it takes a lot of cost and time to build one which consists of multiple companies. Thus, this study proposes a model that automatically classifies the companies that form a value chain based on actual transaction data. A total of 19 transaction attribute variables were extracted from the transaction data and processed into the form of input data for machine learning method. The proposed model was constructed using the Random Forest algorithm. The experiment was conducted on a automobile parts company. The experimental results demonstrate that the proposed model can classify the client companies of the parent company automatically with 92% of accuracy, 76% of F1-score and 94% of AUC. Also, the empirical study confirm that a few transaction attributes such as transaction concentration, transaction amount and total sales per customer are the main characteristics representing the companies that form a value chain.

• Spatial Information Research
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• v.22 no.1
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• pp.65-73
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• 2014

Recently indoor navigation with indoor map such as Indoor Google Maps is served. For the services, constructing indoor data are required. CityGML and IFC are widely used as standards for representing indoor data. The data models contains spatial information for the indoor visualization and analysis, but indoor navigation requires semantic and topological information like graph as well as geometry. For this reason, IndoorGML, which is a GML3 application schema and data model for representation, storage and exchange of indoor geoinformation, is under standardization of OGC. IndoorGML can directly describe geometric property and refer elements in external documents. Because a lot of data in CityGML or IFC have been constructed, a huge amount of construction time and cost for IndoorGML data will be reduced if CityGML can help generate data in IndoorGML. Thus, this paper suggest practical use of CityGML including deriving from and link to CityGML. We analyze relationships between IndoorGML and CityGML. In this paper, issues and solutions for linkage of IndoorGML and CityGML are addressed.

• Korean Journal of Food Science and Technology
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• v.45 no.6
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• pp.791-795
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• 2013

The aim of this study was to compare the performance of a standard culture method and polymerase chain reaction (PCR) for the detection of Staphylococcus aureus (S. aureus) in milk and meat products. Milk, dried infant formula, sausage and ground beef that had been artificially inoculated with S. aureus were enriched in tryptic soy broth. After the enrichment, a loopful was inoculated onto Baird-Parker agar with egg-yolk-tellurite. In parallel, 23S rRNA was amplified by PCR from samples of the enriched broth. Suspected S. aureus colonies grown on selective agars were finally confirmed by a coagulase test and colony PCR. No significant statistical differences were observed between the incidence of S. aureus detected by the culture method and the incidence detected by PCR, in milk or dried infant formula. However, in sausage and ground beef, the number of positives detected by PCR was significantly higher than by the culture method (p<0.05). Our findings suggest that PCR could be an effective screening tool for the detection of S. aureus compared to the standard culture method.