• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.353-357
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• 1995

The purpose of this study was to evaluate the possibility of the laboratory-made rice straw pulp tray(RSPT) for mushroom(Agaricus bisporus) pre-packaging. The quality changes of mushrooms packaged respectively in the RSPT and 'commercial' expanded polystyrene tray(EPST) were observed during storage. The weight losses of mushrooms in the two types of trays were maintained below 5% and the Hunter L values were showed above 76 at $4^{\circ}C$, while mushrooms in RSPTs had better lightness than those in EPSTs during storage at $25^{\circ}C$. There were no significant differences in the hardness values and cap openings between mushrooms in the two types of trays at $4^{\circ}C$. The cap openings of mushrooms were more proceeded in RSPTs than in EPSTs at $25^{\circ}C$ and the weight increases of RSPTs were greater than those of EPSTs during storage at $4^{\circ}C,\;25^{\circ}C$. As a result, it may be favorable to apply the environmentally-friendly RSPT to mushroom pre-packaging under the condition of low storage temperature.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.1 no.1
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• pp.29-37
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• 1995

The purpose of this study was to development the waxed rice straw pulp tray(WRSPT) which had low water sensitivity. The quality changes of mushrooms(Agaricus bisporus) packaged respectively in the WRSPT, non-treated rice straw pulp tray(NRSPT) and expanded polystyrene tray(EPST) were observed during storage. The weight losses of mushrooms in the WRSPTs were less than in the NRSPTs by maintaining below 3% at $0^{\circ}C$ and the applications of WRSPTs were more effective at $20^{\circ}C$. The weight increases of WRSPTs were more lowered than those of NRSPTs by marking below 15% during storage at $0^{\circ}C$. There were no significant differences in the Hunter L values and hardness values of mushrooms in the three types of trays at $0^{\circ}C$. The cap openings of mushrooms were more proceeded in NRSPTs than in WRSPTs and EPSTs at $20^{\circ}C$. As a result, it may be favorable to control excessive moisture absorption of the NRSPT mainly composed of cellulose pulp by introducing such chemical treatments as wax treatment.

• Food Science and Preservation
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• v.16 no.6
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• pp.817-823
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• 2009

We investigated the effects of storage temperature and packaging treatment on the freshness of high-quality 'Fuji' apples to improve consumer confidence in the maintenance of high fruit quality during distribution. A 0.35 mm-deep PET tray form-sealed with a 0.05 mm LDPE film lid was developed and tested with the aim of optimizing gas composition within the package headspace to utilize potential modified atmosphere (MA) storage to maintain the freshness of apples. Weight loss, color difference, firmness, respiration rate, gas concentrations in packages, acidity, solid soluble content, and fruit decay rate were measured during storage at $5^{\circ}C$ and $25^{\circ}C$. The results showed that respiration rate, weight loss, color difference, and firmness were lower and overall quality better during storage at $5^{\circ}C$ compared with $25^{\circ}C$. Also, the fruits packed in the functional tray form showed a low level of quality changes compared with the control (no packaging). The accumulated gasconcentrations in the headspace of the packages decreased from 21% to 12% $O_2$ and increased from 0% to 5% $CO_2$ (v/v) on day 7, and after remained at those levels thereafter. Soluble solid contents and total acidities of the packaged fruits were in the range of $11\;-\;14^{\circ}Brix$ and 0.2 0.3% during storage. Decay rates in the control and packaged fruits were more than 20% and less than 10% at 3 weeks, respectively. Based on the standard acceptable level (less than 10%) of total weight loss, it could be estimated that the shelf life of top-quality fruits packed in functional trays was 3 weeks at $5^{\circ}C$ and 16 weeks at $25^{\circ}C$, whereas the shelf life of the control fruit was 1 week and 12 weeks, respectively. For the top-quality fruit "Fuji" apples, the best results were obtained with a functional tray form for packaging treatment and a storage temperature of $5^{\circ}C$.

• Korean journal of food and cookery science
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• v.3 no.2
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• pp.87-99
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• 1987

The serving temperature control practices were assessed in 20 general hospital's dietetics utilizing centralized or decentralized tray assembly systems. The results of the study were summarized as follows : 1) All of the surveyed hospitals were utilizing conventional foodservice system. The number of dietary employees per bed was very low when comparing with that in America. Working hours of employees per week were approximately two times greater than those in America. 2) When comparing two tray assembly systems, dietary labor hours and costs in centralized system were less than those in decentralized system. 3) When comparing serving temperature practices between two tray assembly systems, the temperatures of meals utilizing centralized tray service were significantly lower than those in decentralized system, and only the steamed rice served in decentralized system was within the acceptable temperature range. 4) There was no significant difference in sensory acceptance scores marked by patients served by two different types of tray assembly systems. The serving temperature was significantly correlated to the patient's overall acceptability.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1726-1732
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• 2008

Injection molding is one of plastic forming technology which can easily mass-produce plastic parts with various and even complex shape. The technology has lots of difficulties in making a good part due to phase change of material, high applied pressure, and fast melt flow speed in the cavity. To overcome the problems, they had to make trial and error method until the CAE(Computer Aided Engineering) could be a tool for concurrent engineering. In this paper, we investigate the optimal design for a plastic DVD tray part by systematic approach of the commercial CAE program. In design, we should consider two objectives which are both dimensional stability and cost-down. The dimension of the part is crucial because the tray should carry a DVD correctly, but the part is too thin to injection-mold easily. In order to improve the moldability, the mold is designed in the form of stack mold which is a kind of 4 hot runner system. In first, we changed the stack-mold system with one hot-runner to cost down, and decided the optimal position of the gate. After that, we investigate the effect of both the layout of cooling channels and the cooling temperature on the shrinkage of the DVD tray. A optimal simulation approach, the gate design is 2Gate#3 and the layout is Case2 cooling line as the optimal temperature of $70^{\circ}C$. The Moldflow and PC+ABS are used for the CAE program and material respectively.

• Journal of Biosystems Engineering
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• v.21 no.2
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• pp.123-133
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• 1996

An automatic drum seeder was developed to improve the seeding operation. It consisted of a conveyor to transfer seedling trays, a seed-hopper to supply seeds, a drum to drop seeds on the tray, and an air blower to remove extra seeds. A photo sensor was used to detect the transfer of seedling trays, and its signal was fed into microcomputer which operated a stepping motor driving the drum. The seeds were adhered to the surface of drum by vacuum pressure, and were dropped into tray cells by compressed air. An air connection unit was devised to alternate between vacuum pressure and compressed air. A control program for the system, written in C language, could operate the drum at the given number of revolutions and revolutions per minute. The results showed that the air connection unit could operate well and the seeds were dropped satisfactorily into tray cells. In case of cabbage and perilla seeds, which are regular and spherical shape, the missing rate was low and the single seeding rate was more than 97%. Low missing rate and high multiple seeding rate were observed in lettuce seeds which have narrow ends with tight weight. The missing rate of pepper seed was very high because of heavy weight and irregular shape. To improve the performance of the seeder, adjustment of vacuum pressure based upon shape and weight of the seeds, careful selection of the material of drum, maintenance of consistent air blower pressure, and replacement of stepping motor to DC motor are recommended.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.85-92
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• 2000

This study was carried out to storage of Pleurotus ostreatus packed in various trays made by different matrials-expanded polystyrene (EPS), rice straw pulp(RP), and RP trays coated with starch, carboxyl methyl cellulose (CMC), polyacrylamide (PAM), alkylketen dimer (AKD), rosin size (RS) and polyethylene glycol (PEG) at 8~1$0^{\circ}C$ and 70~80% relative hymidity for 6 days. At 6 days storage, weight increase of RP and CMC tray was lower (p<0.05) than those of others and the weight of oyster mushroom packed in RP, CMC and AKD tray decreased lower(p<0.05) than those of others. Carbon dioxide contents in trays were increased from 0.5% to 5.5%~8.6% within 1 day storage. Oxygen contents in trays were sharply decreased from 20% to 0.8%~8.2% within 1 day storage. Lightness of oyster mushroom increased all trays. Off flavor appeared stronly in oyster mushroom packed in EPS, AKD and PEG during storage, but was not detected in mushroom packed in starch and CMC until 4 days storage.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.65-66
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• 2008

• Electric Engineers Magazine
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• v.265 no.9
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• pp.14-21
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• 2004

현재 국가간에 IEC를 통하여 국제적인 표준화를 진행 중에 있으나, 이러한 국가간의 표준화가 완료되기 이전이나 혹은 타국과 다른 특성의 제품을 제조 생산하는 경우에는 이와 관련된 내용을 자국의 기술 범위에서 언급을 하고 있는데 국내에서도 잘 알려진 NEMA VE 1-2002/CSA C22.2 NO. 126.1-02(METAL CABLE TRAY SYSTEMS)와 국내의 연구학문도 소개하여 전기계의 기술인들에게 참고 자료가 될 수 있도록 관련기준 위주로 정리하였다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.3 no.3
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• pp.153-160
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• 1991

Heat transfer characteristics of a direct contact heat exchanger utilizing sieve trays and spray nozzles for steam condensation for the purpose of combining with a LNG evaporator have been investigated with various cooling water flow rates and different vacuum pressures within the heat exchanger for the purpose of steam condensation. Temperature profiles and the volumetric overall heat transfer coefficients in a direct contact heat exchanger have been obtained for comparisons. The results show that the temperature differences between cooling water and steam along the direct contact heat exchanger height are rapidly decreasing and the volumetric overall heat transfer coefficients of the exchanger improves greatly as the inside vacuum pressure increases. The values of the overall heat transfer coefficients at P=-680mmHg have been increased significantly compared with at atmospheric pressure. At given pressure conditions, it is found that the values of average volumetric overall heat transfer coefficients for the sieve tray are found to be approximately 10% higher than those of the spray nozzle.