• Journal of the Korean Dietetic Association
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• v.19 no.3
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• pp.195-208
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• 2013

The purpose of this study was to evaluate the quality characteristics of chicken sausage prepared with turmeric (Curcuma longa L.) powder (T) during storage at $4^{\circ}C$ for 20 days. The pH and color values (a and b values) of sausage containing turmeric powder were significantly higher (P<0.05) than the control for both uncooked and cooked sausage. The hardness, chewiness, and gumminess of control sausage significantly changed after 15 days of storage, while the hardness and gumminess of turmeric-supplemented sausages (T) significantly increased after 5 days (until 15 days) for cooked sausages. The total phenolic content and DPPH radical scavenging activity of turmeric-supplemented sausages was significantly higher (P<0.01) than the control for both uncooked and cooked sausage during storage. On the other hand, the acid value of the control was higher than the turmeric-supplemented sausages and the peroxide value of the control was significantly higher (P<0.05) than the turmeric-supplemented sausages after 15 days of storage. Microorganism analysis revealed that total plate counts of uncooked and cooked control sausages were significantly higher (P<0.05) than turmeric-supplemented sausages at 20 days of storage. As a result, sausages prepared with turmeric powder demonstrate antioxidative activity and lipid oxidative stability during storage.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.2
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• pp.105-114
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• 2016

When impact load is applied to a plate structure, a common phenomenon that occurs in structures is plastic deformation accompanied by a large strain and eventually it will experience a fracture accordingly. In this study, for the rational design against accidental limit state, the plastic material constants of steel plate which is formed by line heating and by cold bending procedure have been defined through the numerical simulation for the high speed tension test. The usefulness of the material constants included in Cowper-Symonds model and Johnson-Cook model with the assumption that strain rate can be neglected when strain rate is less than the intermediate speed is verified through comparing the present numerical results with those in references. This paper ends with describing the future study.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.11
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• pp.2136-2149
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• 1992

The natural convection from an inclined ice flat plate immersed in cold water near its density maximum is studied numerically. Finite difference analysis has been performed for the heat and momentum transfer with respect to various inclined angles and ambient water temperatures. The results of the analysis are presented for ambient water temperatures, 1.0deg. C. leq. T／sub .inf.／.leq. 15.0deg. C and the inclined anales from 0deg to 60deg. They include velocity profiles, temperature profiles, melting velocities, and mean Nusselt numbers for entire flow fields, Generally, in the range of 0deg. C .leq.theta. .leq. 60.deg. C, the results show three distinct flow regimes, In the range of 1.0 deg. C .leq. T／sub .inf.／ .leq. 4.6 .deg. C, the greatest mean Nuselt number exists about 3.0deg. C. In the range of 5.7deg. C .leq. T／sub .inf.／ .leq. 15.0deg. C, mean Nuselt number increases as ambient water temperature increases. Also, the mean Nuselt number decreases as the inclined angle increases. This theoretical results are compared with previous experimental ones and multiple steady state ones.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.11
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• pp.1119-1126
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• 2011

In conventional microchannel heat exchangers, only one kind of fluid (hot or cold) flows in each plate. The channels contain different kinds of fluid depending on the vertical position, but they have the same kind of fluid at all horizontal positions. Therefore, there is a slower heat transfer rate in the horizontal direction than in the vertical direction. We propose a microchannel heat exchanger in which hot and cold fluid flows alternately in each plate to improve the thermal performance. This novel channel array requires a special design for the inlet and outlet. The proposed channel array has a faster heat transfer rate than a conventional channel array. The thermal performance of the novel channel array increases with increasing Reynolds number and Prandtl number, but it decreases as the ratio of solid to fluid thermal conductivity increases.

• Journal of the Korean Society of Propulsion Engineers
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• v.3 no.4
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• pp.67-74
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• 1999

Problems created by supersonic jet impinging on solid objects or ground arise in a variety of situations. For example multi-stage rocket separation, deep-space docking, V/STOL aircraft, jet-engine exhaust, gas-turbine blade, terrestrial rocket launch, and so on. These impinging jet flows generally contain a complex structures. (mixed subsonic and supersonic regions, interacting shocks and expansion waves, regions of turbulent shear layer) This paper describes experimental works on the phenomena (surface pressure distribution, flow visualization) when underexpanded supersonic jets impinge on the perpendicular, inclined plate using a supersonic cold-(low system. The used supersonic nozzle is convergent-divergent type, exit Mach number 2, The maximum on the plate when it was inclined was much larger than perpendicular plate, owing to high pressure recoveries through multiple shocks. Surface pressure distribution as to underexpanded ratio showed similar patterns together.

• Journal of Korean Society of Steel Construction
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• v.9 no.4 s.33
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• pp.589-600
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• 1997

Cold-formed deck sections are used in many composite floor slab applications wherein the steel deck serves not only as the form for the concrete during construction but also as the principal tensile reinforcement for the bottom fiber of the composite slab. This paper provides the results of an experimental study performed for the composite slabs with the new shaped deck plates with the locking ribs, the dove tails, and the powerful embossment, which are the mechanical means to improve positive interlocking effect between the deck and the concrete. A total of 28 specimens are tested to investigate the composite effects between the concrete and metal deck plate. Important parameters in this are the span length, the thickness of the deck plate, support condition, and whether shear studs are placed at each support or not. The test results are summarized for the maximum load and failure behavior for the specimens.

• Korean journal of food and cookery science
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• v.32 no.6
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• pp.724-733
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• 2016

Purpose: This study was to evaluate the microbiological quality of salads in lunchbox's based on the holding time and temperature at convenience and franchise stores. Methods: Cabbage salad and crab meat salad were targeted for microbiological quality assessment. They were tested for aerobic plate counts, coliforms, Escherichia coli, Staphylococcus aureus and Enterobacteriaceae and assessment were performed by Korean Food Standards Codex. Results: In cabbage salad at convenience franchise store's at $5^{\circ}C$, the aerobic plate counts did not exceed the Korean Food Standards Codex. For cabbage salad stored at $25^{\circ}C$, the aerobic plate counts was 5.08 log CFU/g we hours after purchase, which exceeded the Korean Food Standards Codex. In case of cabbage salad in franchise store, the E. coli and S. aureus count exceeded Korean Food Standards Codex 3 hours after purchase. Microbiological analysis did not exceed the Korean Food Standards Codex at $5^{\circ}C$ in crab meat salad in convenience store. At $25^{\circ}C$, the aerobic plate count was detected at 4.45 log CFU/g after 32 hours, coliforms, E. coli, and S. aureus did not detect, but Enterobacteriaceae was found to be 2.34 log CFU/g after 9 hours in franchise store's crab salad. Coliforms was detected at 1.18 log CFU/g after 3 hours, and S. aureus was detected at 2.04 log CFU/g after 6 hours at $25^{\circ}C$ in the franchise store. The lunchbox' salad under cold storage ($5^{\circ}C$) generally meet the Korean Food Standards Codex. Conclusion: The results indicate an urgent need to implement proper management guidelines for the production of lunchbox foods to ensure microbiological safety, and to improve the shelf life from production to consumption.

• Transactions of Materials Processing
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• v.23 no.2
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• pp.95-102
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• 2014

The under-drive brake piston is an important component in automotive transmissions. It changes the velocity by controlling the gear ratio. It has been traditionally manufactured by hot forging. Recently, there has been an effort to replace this traditional manufacturing method with cold forging in order to improve the dimensional accuracy and decrease the surface roughness. Cold forging uses a smaller amount of initial material and also has a shorter cycle time since the forged surface can be the final surface without the need of post-processing such as machining or grinding. In the current study, finite element analysis was conducted to evaluate a process design using an initial plate with reduced thickness. This smaller thickness decreases the amount of material needed for the part as well as the machining to produce the final product.

• Advances in aircraft and spacecraft science
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• v.4 no.6
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• pp.701-709
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• 2017

One of the components that used in the satellite thermal control subsystem is the Mechanically Pumped Fluid Loop (MPFL) system; this system mostly used in geosynchronous orbit (GEO) satellites, and can transfer heat from a hot point to a cold point using the fluid which circulated in a closed loop. Heat radiates to the deep space at the cold plate to cool down the fluid temperature. In this research, the radiative heatexchanger (RHX) for a MPFL system is optimized. The genetic algorithm has been used for minimizing the total mass and pressure drop by considering a constant transferred heat rate at the heat exchanger. The optimization has been done in two cases. In case I, two parameters are considered as a goal function, so optimization is performed using NSGA-II method. Results of optimization are shown in the pareto diagram. In case II, the diameter of pipe is considered constant, so the optimized value for distances of the parallel pipes is obtained by using the genetic algorithm, in which the system has the least total mass. Results show that in the RHX, by increasing the pipe diameter, pressure drop decreases and total mass increases. Also by considering a constant value for pipe diameter, an optimum distance between pipes and pipe length are obtained in which the system has a minimum mass.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.8
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• pp.585-592
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• 2007

Good cold start characteristics are essential for satisfactory operation of fuel cell vehicles. In this study, the melting process has been numerically investigated for a water tank used in fuel cell vehicles. The 2-D model of the tank containing ice and plate heaters was assumed and the unsteady melting process of the ice was calculated. The enthalpy method was used for the description of the melting process, and a FVM code was used to solve the problem. The feasibility study compared with other experiment showed that the developed program was able to describe the melting process well. From the numerical analysis carried out for different wall temperatures of the pate heaters, some important design factors could be found such as local overheating and pressurization in the tank.