• The Korean Journal of Ceramics
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• 제6권2호
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• pp.96-99
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• 2000

Particle size of the cement raw materials is important not only in clinker burning but also in cement productivity. Model experiment was designed to investigate the effect of compressive grinding on cement raw materials and clinker granule. Compressive grinding was more efficient in reducing hard materials like quartz. Regression model was constructed to explain the effect of compressive grinding on the size reduction of cement raw materials and clinker.

• 한국축산식품학회지
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• 제33권6호
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• pp.730-736
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• 2013

This study was to establish irradiation process for serving ginseng chicken porridge to immune-compromised patients. Raw chicken, glutinous rice, ginseng, garlic, dried jujube and carrot were used as raw materials for ginseng chicken porridge. The initial level of microorganisms contaminated in raw materials and their predominant species were determined. The level of microorganism detected in raw chicken and in ginseng were 3.4 Log CFU/g and 4.7 Log CFU/g, respectively. Major predominant microorganisms were Pseudomonas fragi in chicken, Enterobactor faecalis in carrot, and Bacillus subtilis in other materials. Chicken and carrot were excluded from irradiation treatment because ordinary thermal treatment can inactivate the microorganisms contaminated in those materials. Five kGy of gamma ray was the effective sterilizing dose required to inactivate B. subtilis in glutinous rice, garlic and jujube, and 10 kGy in ginseng. Ginseng chicken porridge was prepared with each of raw materials gamma-irradiated with the selected sterilizing doses. Control was ginseng chicken porridge prepared with non-irradiated materials. The growth of microorganisms was not observed in the chicken porridge prepared with irradiated raw materials. Sensory results showed that the score of flavor and off-flavor was slightly lower in ginseng chicken porridge prepared with irradiated raw materials than in control. This was considered to be due to the increase of TBARS values by gamma irradiation. However, there was no significant difference on overall acceptance between the porridge prepared with irradiated raw materials and control. The results showed that the individual gamma irradiation of raw materials can be applied to prepare ginseng chicken porridge as meals for the immunocompromised patients.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1990년도 춘계공동학술대회논문집; 한국과학기술원; 28 Apr. 1990
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• pp.100-110
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• 1990

An optimal raw mix model in stainless steel making is developed. The key raw materials in stainless steel making are stainless steel scrap, steel scrap, and alloy materials like Fe-Ni, Fe-Cr. Among those raw materials, the alloy metals are very expensive as well as rapidly price-changing items. Consequently, it is very important to develop an minimal cost raw mix scheme while the produced stainless steel satisfies the required specification in it's composition. The linear programming model is employed to determine the minimal cost raw mix scheme. Compared with the method being used, the developed linear programming model gives much faster and better solution (lower cost raw mix plan). Together with the linear programming model, the database is also developed, which includes the following: 1) data for raw materials, such as compositions, costs, densities, available inventory levels, and so on, 2) the required specifications process. The developed optimal raw mix model will be implemented in VAX computer.

• 한국조리학회지
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• 제4권
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• pp.389-411
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• 1998

The consumption of bread as the principal food is increasing. The taste of bread depends on the components of raw materials. Though the knowledge about the raw materials of bread is important for the development of new products and the cost accounting, it is difficult to find the study on the role of raw materials in making bread. Therefore, the purpose of this study is to integrate the existing theoretical study on bread. Then, it will provide the basic knowledge on the raw materials in making bread in order to develop the technique of making bread.

• 자원리싸이클링
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• 제23권3호
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• pp.51-60
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• 2014

본 연구는 35여종의 희유금속을 대상으로 광석(정광), 금속, 화합물, 스크랩 등 4개 유형으로 광종별 원재료를 범주화하고 교역 구조를 분석하였다. 우리나라 희유금속원재료 교역 규모는 점차 확대되어 교역 증가폭이 GDP 증가폭을 큰 폭으로 상회하고 있다. 희유금속 원재료는 실리콘, 니켈, 크롬, 몰리브덴, 망간 등 철강원료자원 위주로 수입이 주로 이루어지고 있으며 전자공업원료자원 중 인듐, 게르마늄 등은 총교역규모 1억불 이하의 작은 규모로 수입추이변화에 미치는 영향은 제한적이나 연간증가율이 20%를 상회하여 지속적인 수급관리가 필요하다. 수입규모는 수출규모의 약 3배이며 희유금속 원재료 수출입 유형은 국내산업구조 및 수요의 특성에 따라 광종별로 다양한 양상을 보이고 있으나 수입, 수출 모두 상당수가 금속형태로 교역이 이루어지고 있다.

• 한국세라믹학회지
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• 제18권4호
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• pp.219-228
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• 1981

To clarify influences of silicious raw materials on mineralogcal and petrological properties in clinkering process clay, shale, quartzite, sand and coal ash have been used as silicious raw materials. The tests on thermal properties, reactivity and burnability of raw mixtures which have different silicious raw materials respectively have been made by means of X-ray diffractometry, differential thermal analysis, optical microscopy and transmission electron microscopy. Limestone contains coarse crystalline grains which show 0.1-1.0mm and its decarbonation temperature is 86$0^{\circ}C$. Reaction temperatures among raw mixtures have been determined by X-ray diffractometry and their results are as follows; clay minerals under 1, 00$0^{\circ}C$, mica group, 100$0^{\circ}C$-110$0^{\circ}C$, feldspar group, 1, 10$0^{\circ}C$-1, 20$0^{\circ}C$ and quartz 1, 20$0^{\circ}C$-1, 30$0^{\circ}C$. Burnabilities of raw mixtures of different temperatures have been found that they mainly depend upon their mineral contents in silicious raw materials and their order is as follows; $clay\geq shale\gg quartzite \geq sand$.

• 식품과학과 산업
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• 제49권2호
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• pp.78-82
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• 2016

DB Integration website(tentatively named Food Processing Aptitude Information Center, FPAIC) has been designed through a "high-value products development project(2013)". Basically, the project aims to secure connections between food raw materials and processing industry, a variety of information sources, and users's convenience. It also aims to build the industry-university-based mutual growth in the food industry through sharing of processing suitability and material research on food raw materials. FPAIC consists of raw material story, information of sample characteristics, food processing study, preceding research data, food industry trends, and understanding of food processing. The major database of research on Food Processing is provided on information of sample characteristics, and food processing study. Currently the web site has 36 raw material stories, 380 information on sample characteristics and food processing studies, 1,600 preceding research data about 31 food raw materials. The web site also provides information on 70 useful web sites, as well as 77 food industry trends, 27 basic information about food processing.

• 시멘트 심포지엄
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• 1호
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• pp.56-63
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• 1973

In cement industry in which three or more raw materials are used, the proportioning of raw materials is an essential step. When the materials are proportioned, each should be as nearly homogeneous chemically and physically as conditions permit. Most of th

• 무역학회지
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• 제47권2호
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• pp.133-154
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• 2022

The Baltic Capesize Index (BCI), which is used as an indicator for marine transportation of steel raw materials, is one of the key economic indexes for managing the risk of loss due to rapid market fluctuations when steel companies establish business strategies and procuring plans for raw materials. Still, the conditions of supply and demand of steel raw materials has been extremely affected by volatility shocks from drastic events like the financial crisis such as the Lehman Brothers incident and changes in the external environment such as COVID-19. And, especially since the 2008 financial crisis, endeavors to predict the market conditions of the steel raw material is becoming more and more arduous for the deepening uncertainty and increased volatility of BCI, which has been used as a leading indicator of the real economy. This study investigates the correlation between the steel raw material market and the marine transportation market by estimating the spillover effect of information between markets. The vector error correction model (VECM) was used to analyze information transfer based on the correlation between the BCI and crude steel production, capesize fleet supply, raw material price, and cargo volume.

• 한국재료학회지
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• 제20권4호
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• pp.181-186
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• 2010

Since it was developed by Joseph Aspdin, cement has been a common construction materials up to the present time. However, there are trace constituents in cement clinker. One of the trace constituents included in cement clinker, chromium, has become prominent and highly noticed lately as a social issue both inside and outside of this country because it affects the human body negatively. The aim of the present study was to investigate the concentration of water-soluble hexavalent chromium in cement clinker by using industrial by-products. For that reason, raw materials were prepared to add different $SiO_2$, $Al_2O_3$, and $Fe_2O_3$ sources. After the raw materials such as the limestone, the sand and the clay, iron ore was pulverized and mixed, and the raw meal was burnt at about $1450^{\circ}C$ in a furnace with an oxidizing atmosphere. The part in the raw materials of the clinker was substituted with slag, sludge, etc. and this was used to manufacturing cement clinker. To investigate the water-soluble hexavalent chromium content in clinker, raw meal was prepared by changing the modulus, the type, and the content of clinker materials and tested concentrations of hexavalent chromium in the clinkers. To determine $Cr^{+6}$ formation of the clinker, tests were done with raw meals adding chromium by using different industrial by-products. Consequently because the chromium was to be included in the raw materials of the clinker, production of Portland cement clinker was included with the chromium. Also, the chromium was converted into hexavalent chromium in the burning process.