• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.413-418
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• 2002

The dough was frozen either before or after fermentation at the five different freezing and storage conditions. Although fermentation before freezing was effective for rapid freezing, it reduced bread volume of the dough frozen at both air freezer and liquid immersion freezer. Freezing at the air freezer set to $-70^{\circ}C$ took more time for freezing and resulted in lower bread volume than freezing at the immersion freezer set to $-20^{\circ}C$. Therefore, the freezing in the liquid immersion freezer was more effective to reduce the freezing time and increase the bread volume. At the liquid immersion freezer, the higher temperature was more effective than lower temperature. The doughs frozen in a liquid immersion freezer set to $-10^{\circ}C$ and fermented after de-frosting produced higher bread volume than control unfrozen dough. And also there was no significant difference in bread volume between the control unfrozen dough and the dough frozen in a liquid immersion freezer set to $-10^{\circ}C$, fermented before freezing and re-fermented after defrosting. The longer proof time and greater loaf volume obtained for the dough frozen and stored at the air freezer set to $-70^{\circ}C$. Therefore the optimum process for freezing the dough was freezing immediately after mixing, storing at $-10^{\circ}C$ in a liquid immersion freezer and fermented after defrosting.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.6 s.261
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• pp.574-580
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• 2007

The objective of this article is to present an analysis of all heat transfer paths through the energy nose under closed door conditions when refrigeration system of household refrigerator-freezer is operating on. Both experimental and numerical methods are suggested as a means of determining the overall energy nose load amount as well as the load due to each pathway such as mullion section and F and R sides of the household refrigerator-freezer. In other words, all loads determined in this article are just energy nose and not the loads seen by the refrigeration system. We suggest good ideas for improving the heat transfer losses such as conduction and convection through the energy nose. As we can be known from the experimental test results, it is effective to prevent the heat loss of a mullion section. And energy efficiency is also decreased approximately 6% compared to that of a baseline sample test result. As we can be known from the Ansys 8.1 analysis, it is shown the steady state temperature distribution in figures from 6 to 8. And the direction of the heat flow through the energy nose section is also easily seen from that In conclusion, the article is focused on an energy nose section in household refrigerator-freezer for practical proposes which is the energy saving in a household refrigerator-freezer. And the method suggested may be applied to any make or model to aid in the search for high efficient energy nose section of household side by side refrigerator-freezer as well as top mounted refrigerator-freezer, commercial refrigerator and so on.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.918-925
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• 2015

An investigation was conducted to evaluate the hygienic status of 33 high school foodservice systems in Yongin city by using hygiene management guide checklist, ATP bioluminescence assay and microbe inspection petrifilm (APC, coliform group, Staphylococcus aureus) of food utensils during use. The 22 hygiene management guide checklist items about facilities, personal hygiene, food control, distribution, washing and disinfection had good grade but there were some inadequate behaviors on observation. The inspection results showed their sanitary condition met the level B of the recommendation of Korea method, it means sanitary management system get settled but more practical CCP system was needed. ATP bioluminescence assay was conducted on surface of food facilities, ATP ranged 425~2,552 RLU on gloves, 541~70,251 RLU on apron, 1,596~88,490 RLU on working desk, 1,177~263,813 RLU on sterilizer grip, 715~32,814 RLU on sterilizer shelf, 114~619,725 RLU on refrigerator grip, 677~319,007 RLU on refrigerator shelf, 71~196,725 RLU on freezer grip, 1,535~233,375 RLU on freezer shelf. APC ranged $66.7{\pm}29.0CFU$ on freezer grip, $102.1{\pm}35.9CFU$ on refrigerator grip, $45.4{\pm}28.2CFU$ on heating cabinet grip, $58.8{\pm}40.4CFU$ on sterilizer grip, the number of coliform group ranged $5.6{\pm}4.9CFU$ on freezer grip, $9.1{\pm}8.7CFU$ on refrigerator grip, $1.2{\pm}1.1CFU$ on heating cabinet grip, $4.5{\pm}4.4CFU$ on sterilizer grip. S. aureus ranged $8.0{\pm}5.6CFU$ on freezer grip, $12.2{\pm}9.6CFU$ on refrigerator grip, $2.1{\pm}1.6CFU$ on heating cabinet grip, $11.6{\pm}6.4CFU$ on sterilizer grip.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.2
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• pp.95-102
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• 2003

Optimization for the insulation thickness and external shape of a household refrigerator is peformed in order to minimize thermal load through the insulation wall. The one dimensional conduction heat transfer model is adopted to calculate thermal load. Calculus of variation is employed to optimize the thickness and shape of refrigerator or freezer. The uniform distribution of an insulation thickness and cubed external shape make thermal load minimize. Finally, by using both of the computational and experimental method, the thermal load is minimized for a refrigerator/freezer. It is shown that there exists optimal thickness of insulation walls and external shape for given the external cabinet dimensions and freezer and refrigerator internal volumes, Also, the analytical results are well agreed with the experimental results.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.686-691
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• 2000

Animation technique from the PIV database is particularly emphasized to give macroscopic and Quantitative description of complex flow fields. As an example, an experimental study was carried out investigate the fundamental (low characteristics of the freezer with the domestic refrigerator. Optimized cross correlation identification to obtain velocity vectors is implemented by direct calculation of correlation coefficients. Image intensifier CCD camera to cope with illumination problem is arranged for the accurate PIV measurement of large flow field. As a results, continuous pictures of the spatial distribution of the instantaneous and time-mean velocity distribution are displayed in real-time sense.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.135-136
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• 2014

In this study, the experimental study on the early age compressive strength of cement mortar using anti freezer and hardening accelerator at low temperature was conducted. For this study, all of materials for experiment were kept in a low temperature for 24 hours before mortar mixing. After mortar curing at low temperature, compressive strength was measured at the early ages. Furthermore, properties of hardened cement material was analysed using TG-DTA and MIP.

• Journal of the Korea Institute of Building Construction
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• v.16 no.5
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• pp.405-412
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• 2016

In order to examine the possibility of practical use of concrete at low-temperature environment using high early strength cement with cold resistance admixture, an experimental study on workability, freezing temperature and compressive strength of the mortar with different types of anti-freezer, water reducing agent and accelerator for freeze protection at low-temperature were evaluated. Compressive strength was increased in use of anti-freezer, especially SN anti-freezer was higher than CN anti-freezer. 0min flow was increased, the 20min flow was decreased. And 20min flow was improved in use of FR, RT water reducing agent. CF, LS accelerator for freeze protection, regardless of the type of water reducing agent, compressive strength was increased.

• Mycobiology
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• v.39 no.2
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• pp.133-136
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• 2011

Mycelial growth and survival ratio of ectomycorrhizal fungi were determined after storage at $-70^{\circ}C$ for 1, 3, or 6 mon. Seventeen of 23 ectomycorrhizal fungi did not survive after storage for more than 6 mon, whereas Cenococcum geophilum, Lepista nuda, and some species of Rhizopogon and Suillus did survive.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.2
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• pp.89-96
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• 2020

In this study, we developed a finite element model for the built-in bottom-freezer type refrigerator and then used the structural analysis method to analyze and evaluate the deflection of the doors. We tested the validity of the developed analytical model by measuring the deflection of the hinge when loads were applied to the upper and lower hinges of the refrigerating compartment and compared these with the analysis results. The comparison of the vertical displacement of the measured result and the analysis result showed an error ratio of up to 12.8%, which indicates that the analytical model is consistent. Using the analytical model composed of the cabinet, hinges and doors, we performed analyses for two cases: both doors closed, and the refrigerating door open. Since the maximum vertical displacement of the refrigerating compartment door (R-door) with the food load is smaller than the gap between the lower surface of the R-door and the upper surface of the freezer compartment door (F-door), it is judged that the R-door and the F-door do not contact when the doors are opened or closed. In addition, the analysis result showed that the difference between the vertical displacement at the hinge on the opposite side and the hinge side of the R-door is favorably smaller than the management criterion of the refrigerator manufacturer.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.5
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• pp.420-427
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• 2016

The marine equipment companies expanding facility investment in accordance with the booming economy are suffering from the reduced demand and the growth of chinese businesses. In this regard, the risk of overinvestment and the importance of prudent equipment investment must be reconsidered. Thus, in this study we performed a productivity and economical efficiency analysis in order to evaluate the investment value on production facilities in a company under the present conditions. The freezer of a fishing vessel manufactured by N company is selected as the subject of our study, while the assembly and welding cooling plates are configured as the scope of automation. Analysis on productivity and economical efficiency was conducted through CYCLONE (Cyclic Operation Network) simulation and economic analysis methods after analyzing the production process of freezer. The proposed analytical technique can be used to support the investment decision in production automation equipment of fishing vessels freezer.