• 산업경영시스템학회지
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• 제42권2호
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• pp.28-35
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• 2019

Since guided missiles with the characteristics of the one-shot system remain stored throughout their entire life cycle, it is important to maintain their storage reliability until the launch. As part of maintaining storage reliability, period of preventive test is set up to perform preventive periodic test, in this case failure detection rate has a great effect on setting up period of preventive test to maintain storage reliability. The proposed method utilizes failure rate predicted by the software on the basis of MIL-HDBK-217F and failure mode analyzed through FMEA (Failure Mode and Effect Analysis) using data generated from the actual field. The failure detection rate of using the proposed method is applied to set periodic test of the actual guided missile. The proposed method in this paper has advantages in accuracy and objectivity because it utilizes a large amount of data generated in the actual field.

• 한국가금학회지
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• 제23권4호
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• pp.203-207
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• 1996

This experiment was carried out to find out the effects of packing methods on shelf-life and hy-giene of breast and thigh meats in chicken. The carcass weights were about 1.6 kg per bird, and chilled by air spray method. The breast and thigh meats were packed by either vacuum or atmosphere packing methods. Samples were analyzed at 1, 4, 8, 12 and 16 wk after quick freezing at -45˚C for 35 min. Regardless of packing method. The thiobarbituric acid(TBA) values of thigh meats after 1 wk of storage were higher than those of breast meats. The TBA values of both treatments were increased as storage period extended. In addition, the TBA values of vacuum packed meats were lower than those of atmosphere packed meats. The VBN(volatile basic nitrogen) values, regardless of packing method, at 1 wk of storage were higher than those of breast meats. The VBN contents of breast and thigh meats after 16 wk of storage increased markedly, but failed to show significant difference between the two packaging methods. Total plate counts of breast and thigh meats were increased gradually as storage period extended, and the total plate count of breast meat was higher than that of thigh meat. The coliform bacteria were not detected until 16 wk after storage.

• 한국치위생학회지
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• 제20권1호
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• pp.73-83
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• 2020

Objectives: This study aimed to measure the knowledge of dental hygienists regarding dental waste, and identify the relationship between general characteristics and infection control characteristics. Methods: This study was conducted using a self-reported questionnaire in 250 dental hygienists. The questionnaire consisted of 21 items: storage container (5 items), storage locations (5 items), storage period (9 items), and storage method (3 items). The collected data were analyzed using the t-test and analysis of variance. Results: The education experience of infection management within the last year was reviewed for significant differences among dental hygienists regarding storage container and storage periods (p<0.05). Statistically significant differences were observed regarding the knowledge of storage container, storage locations, storage period, and storage method among the enrolled dental hygienists (p<0.05). Conclusions: This study examined the necessity of developing conservative education and job education programs to improve the knowledge level of dental hygienists regarding dental waste management.

• 한국지열·수열에너지학회논문집
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• 제15권1호
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• pp.9-17
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• 2019

Reducing global warming potential has become important, and as one of those methods for reducing it, economic evaluation by applying ice thermal storage air conditioning system was performed. The floor area and height of the subject building was assumed $5,000m^2$ and 20 m. Absorption chillerheater system and air source heat pump system was used for comparing to the subject system, and payback period method was used to perform economic evaluation. Although the running cost of ice thermal storage system is reduced compared to two systems, the ratio is not significant compared to the increase of initial construction expenses, and payback period was calculated to be about 7.7 and 79.3 years. However, the heat storage system should be approached from the viewpoint of long term rather than the economic standard in the present standard.

• 한국식품영양학회지
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• 제25권4호
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• pp.1033-1038
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• 2012

This study was done to provide basic information about the storage and distribution of specialty grade coffee of which the market will be expanded through customer sensory evaluation according to the storage period of specialty grade coffee by the SCAA classified method with consideration to defective beans and scent. The specialty grade coffee sample of this study was extracted on day 1, day 14, and day 28. The water content showed a significant reduction on the 28th storage day and there was no pH change according to the storage period. Color degree was brightened according to the preservation period before and after grinding but there was no significant difference. The panels for sensory evaluation considered of 24 university. The sensory evaluation consist of aroma, bitterness, and astringency, acidity, aftertaste, overall satisfaction, and items for strength estimation consist of aroma, acidity and bitterness. The sensory evaluation was expressed by applying a 5 point Likert scale. The results showed that as the storage period increased so too did the aroma and the strength of bitterness. Preference was the highest on day 1 in every items except aroma and astrigency. However on day 14 and day 28, most of the sensory evaluation became low and then became high, which was inconsistent. Male students were not consistent in their evaluation according to the preservation period, but female students rated aroma and bitterness the lowest on preservation period day 1 and they prefer after a storage period of 1 day in regards to the entire degree of satisfaction including sour test. astrigency and aftertaste. The analysis of visiting frequency for coffee shops used demonstrated that the longer the preservation period, the lower the preference but was not significant in the case of involving a little frequency group. The group that did not like Americano coffee evaluated that the longer the preservation period, the lower the preference based on Americano coffee preference analysis. There was no consistency between the storage period day 14 and day 28 in strength and preference, but preference for storage period day 1 was high in every group, which means that the quality of coffee is affected by the preservation period.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.286-291
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• 2001

This paper describes an optimal scheduling for ice slurry systems for energy cost saving. The optimization technique applied in the study is the dynamic programming method, for which the state variable is the storage in the ice storage tank and the control variable is the state of chiller's on-off switching. Though the costs during charge period is included in optimization by taking the average cost of ice per hour for slurry making, the time horizon for the simulation is limited building cooling period because accurate charge rate from the ice maker into the ice storage tank cannot be estimated during the charge period. In the operating simulation after optimizing procedure, energy consumption and operating cost for the optimal control are calculated and compared with them for a conventional control with one case of cooling load profile.

• 한국식품영양학회지
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• 제36권4호
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• pp.236-243
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• 2023

The purpose of this study was to investigate the effects of sterilization, storage period and washing yuzu, according to the washing method, during the storage period. The results showed that the fungus size increased as the storage period increased, and no mold occurred in the yuzu washed with ozone water until 20 days. After 30 days of storage, a mold of 124.1±13.9 mm² was observed. The no-treatment sample had a fungus of 814.5±72.8 mm² in size on day 0 and the fungus the largest fungus was 6,362±636.7 mm² on day 30. In the case of water treatment, the fungus was 286.4±31.5~4,836.4±484.6 mm² in size. The results of the study confirmed that washing yuzu with ozone water has a sterilizing effect.

• 한국식생활문화학회지
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• 제9권1호
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• pp.87-93
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• 1994

This study was conducted to present a method that determine the optimum conditions for the preparation of chinese whole cabbage kimchi. After Sensory and chemical characteristics of kimchi with various salt concentration in brine, brining time and storage period at equal saltiness were measured, the optimum conditions for the preparation of chinese whole cabbage kimchi were determined with the use of the response surface methodology. The results are summarized as follows; 1. The more salt concentration in brine, the longer brining time and storage period, resulted in the lower pH and the higher titratable acidity of kimchis. As the salt concentration in brine and brining time increased, kimchi reaches at optimum titratable acidity of it within a shorter time. 2. As the salt concentration in brine and brining time increased, content of succinic acid decreased but that of lactic, acetic, and propionic acid increased. Amount of citric, malic and succinic acid decreased but that of lactic, acetic acid increased, with storage day. 3. Sensory data showed that firmness and green cabbage flavor of kimchi decreased while toughness, carbonic mouthfeel, sourness and staled flavor increased with increased salt concentration in brine, brining time and storage day. As the storage period increased, crispness of kimchi decreased. 4. The optimum conditions for the preparation of chinese whole cabbage kimchi were as follows: Optimum salt concentration in brine, brining time, and storage period were 19.5%, 3 hours and 45 minutes, and 12 hours.

• 한국식품영양학회지
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• 제13권1호
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• pp.21-27
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• 2000

In order to investigate the changes of rice qualities during 4 years storage of paddy in warehouse of normal temperature condition. As storage period go by, head ratio was deduced and broken rice was increased according as a change of temperature during the long term storage. A color of rice was became more dark gray than that of entering time as L value was decreased from 64.07 to 61.62 a 4 years late. As a results of studies on the cooking quality of milled rice, water uptake ratio and expanded volume were increased in proporation to storage period, wherease total solids and iodine blue value were decreased. In the characteristic of texture of cooked rice, viscosity/hardness ratio(-H/H) had a decreasing tendency, while adhesiveness and cohesiveness increased with increased storage time. The qualities of cooked milled rice studied were sensory attributies of odor, taste, stickiness and appearance which were evaluvated by multiple comparsion method. The sensory results showed that all of descriptions were deterirated with a increased storage period. The taste and stickiness were changed from good score to bad score a 2 years later.

• 한국식품조리과학회지
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• 제16권6호
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• pp.511-520
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• 2000

약포의 첨가당과 건조방법이 육포의 품질과 저장성에 미치는 영향을 알아보기 위하여 저장상, 기계적 특성과 관능검사를 실시하였다 육포의 저장 기간 중에 수분활성 도는 경시적으로 감소경향을 나타내었고 저장 5주에는 꿀과 조청을 첨가한 천연건조시료(N-H, N-R)가 모두 0.71로 가장 낮은 값을 보였다. 모든 시료의 pH는 저장에 따라 감소하였으며 꿀을 첨가하여 열풍 건조한 육포(H-H)가 5.22로 가장 낮았다. 색도의 L, a, b값은 저장기간 중에 모두 감소 경향을 보였다. 저장기간 중 모든 시료에 있어서 TBA값이 증가하는 것으로 나타났고, 설탕시립첨가육포(N-S, H-S, S-S)는 건조방법과 관계없이 가장 낮은 값을 보였으며 꿀첨가육포(N-H, H-H, S-H)가 가장 높았다. 모든 시료의 총미생물수와 젖산균수는 저장 기간이 경과함에 따라 증가하였으며, 저장 5주시 설탕시럽첨가 열풍건조한 육포(H-S)가 가장 낮았다. 모든 시료의 기계적 조직특성은 저장기간이 경과함에 따라 증가하였다. 탄력성과 응집성은 대체로 꿀첨가시료가 가장 높았고 씹힘성과 점착성·견고성은 설탕시럽첨가 천연건조 시료가 가장 높게 나타났다. 천연건조시료는 포장방법에 관계없이 거의 모든 항목에 걸쳐 저장기간이 경과함에 따라 관능점수가 감소하였고, 열풍건조시료들의 관능점수는 포장방법에 관계없이 천연건조시료들에 비해 현저히 높은 점수를 나타내었다.