• Journal of Dairy Science and Biotechnology
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• 제22권1호
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• pp.27-35
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• 2004

The shelf lift of market milk should be determined based on the flavor which is influenced by environmental and sanitary conditions of dairy farm, milk processing plant, and storage and transportation facility as well as compositional quality, such as protein and fat, of the milk itself. The legal shelf life of market milk is often limited by microbiological quality, e.g. total bacterial count, coliform count, and food poisoning bacteria. The bacteria involved with milk spoilage and poisoning are originated from bacteria contaminating milk after pasteurization or spores surviving the heat treatment of pasteurization. The important factors which influence the shelf life of market milk are microbiological quality of raw milk, pasteurization condition, post-pasteurization contamination, and temperature during storage and transportation. The organoleptic quality and shelf life of market milk should be further improved by satisfying the consumer's taste, which depends on somatic cell count and bacterial count of milk, feed quality, foreign substance in milk, and physical treatment during processing and transportation.

• 한국포장학회지
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• 제11권2호
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• pp.97-100
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• 2005

To delay the fermentation of Kimchi during storage and handling, adipic acid, was selected due to its low acid dissociation constant. Sensory evaluation was conducted to find maximum dosage of adipic acid which does not influence the raw taste of Kimchi and 0.12%(wt. of adipic acid/wt. of Kimchi) was selected. At $10^{\circ}C$, the optimum and maximum shelf life was respectively 3.2 and 2.3 times longer than that of control. At 15 and $20^{\circ}C$, extension of shelf life was as follows: maximum shelf life with adipic acid was extended about 2.3-2.7 times and optimum shelf life was 1.3-1.5 times.

• 생명과학회지
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• 제10권1호
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• pp.61-67
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• 2000

An experiment was conducted for extension of shelf-life of cooked squid (Todarodes pacificus) using modified atmosphere packaging. The products were packed in a Ny/PE/LLDPE (0.015/0.045/0.040 mm) laminated film with air, vacuum, CO2 gas, and N2 gas, respectively, and then stored at 5$^{\circ}C$ and 2$0^{\circ}C$. Keeping qualities of the products were investigated by measuring moisture content, H, volatile basic nitrogen (VBN), viable cell count, thiobarbituric acid (TBA) value, peroxide value (POV) and color value. Good qualities of the products stored at 5$^{\circ}C$were maintained at least 9 days, 11 days, more than 35 days and 24 days in air, vacuum, CO2 gas and N2 gas packaging products, respectively. In cases of 2$0^{\circ}C$ storage, however, the shelf-lives of all the products were only one day. The shelf-life extension of the products were observed in CO2 ga>N2 gas>vacuum>air packaging in order.

• KIEAE Journal
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• 제17권3호
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• pp.5-13
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• 2017

Purpose: Various studies have been performed to address the issue of increased energy use by buildings. In particular, research on complex envelopes that combines diverse envelope element techniques is currently in progress in the building sector. The present study aimed to develop an awning system using a light shelf, and to verify its validity through performance evaluation. Method: In the present study, a testbed was established for the performance evaluation of the awning system using a light shelf, and the uniformity ratio and lighting energy consumption were compared and analyzed relative to those with no awning and light shelf installation (Case 1), awning installation (Case 2), and light shelf installation (Case 3). Result: 1) In the present study, an awning system using a light shelf (Case 4) where an opening is made on the awning screen and natural light can be introduced through the light shelf located at the bottom was developed. 2) The optimum standard for Case 4 obtained through the performance evaluation was a 0.6m lighting length and a 2m extension length at a light shelf angle of $30^{\circ}$. 3) Case 4 with the optimum standard had a 5.5% lower uniformity ratio than Case 2, but had a higher uniformity ratio than Case 1 and Case 3. 4) Case 4 with the optimum standard showed 13.3%, 44.6%, and 0%~8.7% lighting energy reductions compared to Case 1, Case 2, and Case 3, respectively. 5) Based on the above results, Case 4 suggested in the present study was found to be effective for indoor light environment improvement and lighting energy reduction.

• 설비공학논문집
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• 제26권6호
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• pp.275-286
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• 2014

Light shelf is an efficient system that reduces the energy consumption by bringing the natural light down to the deep spaces inside of a building. However, the existing light shelves have limits in reducing energy usage, because the direction of the light flow is determined by the external environment such as the altitude of the sun and the azimuth. This current study presents a system that increases the efficiency of the light shelf by applying the Location-Awareness technology, in which the efficiency was verified through the performance evaluation. According to the examination of the technology for the Location-Awareness within residential space, 'Zigbee' type appears to be the most appropriate. The Location-Awareness technology operates the light shelf based on both the angle control axis and the light shelf angle control axis through the modularization of the reflector surface which is less affected by the external environment. The results of the performance evaluation showed that the movable light shelf that employs the Location-Awareness technology can reduce the energy consumption for lighting by 98.3% compared to the fixed light shelf and by 97.3% compared to the movable light shelf without Location-Awareness.

• 한국태양에너지학회 논문집
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• 제23권3호
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• pp.63-71
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• 2003

According to the recent report, the lighting energy consumption of commercial buildings reaches to $30%\sim40%$ of the total energy consumption. It is more than that of cooling & heating energy consumption and it is the major target of energy-saving policy. It is obvious that they are interested in natural lighting device such as Light-shelf for the purpose of raising the lighting energy-saving efficiency. In most of highly developed countries, a thorough study on Light-shelf makes it possible to propose a practical plan while at home there leaves much to be desired to study a guiding principle of optimum plan in spite of its efficiency based on experiments using scale4 model and analysis of simulation. Aiming at making an optimum plan of Light-shelf suitable for the domestic situation, this study is worked by experiments using light-shelf and analysis of variables using illumination program. The experiments is to analyse the efficiency of Light-shelf on condition of the sky and the analysis is to make the simulation using illumination program. This study is composed of 1) the analysis of light with some variables such as presence of light-shelf and degree of angle using 1/2 scaled model 2) making the simulation using Lightscape, illumination program, In brief, concerning presence of light-shelf, it causes little difference in its efficiency in the overcast sky, whereas it decreases an illuminance of window side and provides inner side with the light, which decreases the ratio of the maximum to the minimum inner illuminance and makes the inner of illuminance to range evenly in the clear sky. On degree of angle, as the daylight increases in proportion of degree of angle, the ratio of the maximum to the minimum inner illuminance decreases, which makes it possible to increase the proportion of inner daylight.

• Ocean and Polar Research
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• 제27권3호
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• pp.277-288
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• 2005

Spatial distribution and vertical structures of water masses around the Antarctic continental margin are described using synthesized hydrographic data. Antarctic Surface Water (AASW) over the shelf regime is distinguished from underlying other water masses by the cut-off salinity, varying from approximately 34.35 to 34.45 around Antarctica. Shelf water, characterized by salinity greater than the cut-off salinity and potential temperature less than $-17^{\circ}C$, is observed on the Ross Sea, off George V Land, off Wilkes Land, the Amery Basin, and the Weddell Sea, but in some shelves AASW occupies the entire shelf. Lower Circumpolar Deep Water is present everywhere around the Antarctic oceanic regime and in some places it mixes with Shelf Water, producing Antarctic Slope Front Water (ASFW). ASFW, characterized by potential temperature less than about $0^{\circ}C$ and greater than $-17^{\circ}C$, and salinity greater than the cut-off salinity, is found everywhere around Antarctica except in the Bellingshausen-Amundsen sector. The presence of different water masses over the Antarctic shelves and shelf edges produces mainly three types of water mass stratifications: no significant meridional property gradient in the Bellingshausen and Amundsen Seas, single property gradient where ASFW presents, and a V-shaped front where Shelf Water exists.

• 한국수산과학회지
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• 제24권6호
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• pp.428-436
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• 1991

영향성 대륙붕에서는 서로 반대 방향으로 진행하는 두 집합의 대륙붕파가 생성된다. 두 대륙붕이 충분히 떨어질 경우에는 두 집합의 대륙붕파는 독립된 대륙붕파가 되며 이 파들은 하나의 대륙붕 지형의 대륙붕파와 일치한다. 그러나 두 대륙붕의 간격이 Rossby Deformation Radius 보다 가까울 때는 두 집합의 대륙붕파는 두 대륙붕 지형에 영향을 받게 된다. 영향성 대륙붕에서도 대륙붕파는 북반구에서 해안선을 오른쪽에 두고 진행한다. 군속도(group velocity)는 장파인 경우에는 파의 진행방향과 같으나 단파인 경우에는 반대가 된다. 그러므로 각 대륙붕파는 어떤 중간의 파장에서 0인 군속도를 갖게 된다.

• Food Quality and Culture
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• 제3권2호
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• pp.74-81
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• 2009

This study investigated consumers' recognition on shelf life of health functional foods to set up their rational expiration date. For this study 107 male and female adults aged 20 to 59 years were randomly selected as major consumers of health functional foods. And their data were analyzed with SPSS 17.0. The questionnaire included questions asking a consumer's recognition on the shelf life of health functional foods and how to treat health function food passing its shelf life. In this study, the consumers were found to pay attentions considerably to the shelf life. But most of them did not know an accurate meaning of the shelf life of health functional food and mistook it for expiry date. In addition, the consumers doubted safety of health functional foods passing the shelf life. Therefore, education for consumers about an accurate meaning of the shelf life was needed. The results of this study were considered to be helpful to set up a reasonable expiration date for health functional food.

• 한국식품저장유통학회지
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• 제5권4호
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• pp.392-395
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• 1998

포장식품의 유통기한 표시기법에 대한 대구ㆍ경북지역 소비자 222명의 심리를 설문조사 방법을 통하여 분석한 결과 소비자들은 포장식품의 유통기한 표시가 매우 중요한 정보라고 생각하고 있었으나 불분명한 유통기한 표시에 매우 혼란스러워 하고 있었다. 유통기한의 중요성에 대한 인식은 식품의 부패성향이 클수록 높았다. 유통기한이 지난 제품에 대해 대부분의 소비자들이 식용을 꺼리고 있었으며 역시 부패성향이 클수록 높았다. 소비자들이 가장 선호하는 표시기법은 선도유지기한 또는 유효기한이었고 포장일자가 가장 낮았다. 인구통계학적 상관관계를 조사한 결과 나이가 어리고 여성의 경우 유통기한이 제품선택에 있어서 보다 중요한 요소로 작용하였다.