• Ocean and Polar Research
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• v.35 no.2
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• pp.135-146
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• 2013

This study investigates the characteristic of the Tsushima Warm Current from an assimilated high resolution global ocean prediction model, $1/12^{\circ}$ Global HYbrid Coordiate Ocean Model (HYCOM). The model results were verified through a comparison with current measurements obtained by acoustic Doppler current profiler (ADCP) mounted on the passenger ferryboat between Busan, Korea, and Hakata, Japan. The annual mean transport of the Tsushima Warm Current was 2.56 Sverdrup (Sv) (1 Sv = $10^6m^3s^{-1}$), which is similar to those from previous studies (Takikawa et al. 1999; Teague et al. 2002). The volume transport time series of the Tsushima Warm Current from HYCOM correlates to a high degree with that from the ADCP observation (the correlation coefficient between the two is 0.82). The spatiotemporal structures of the currents as well as temperature and salinity from HYCOM are comparable to the observed ones.

• Transactions of Materials Processing
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• v.10 no.3
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• pp.253-260
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• 2001

This study was performed to investigate the optimized warm forming conditions which gave the maximum drawing depth in square cup drawing of clad sheet metals, by changing the temperatures of die and blankholder and also shapes and materials of blanks. Two kinds of clad sheet metals, STS304-A1050-STS304 and STS304-A1050-STS430 were selected for experiments. The relative drawing depth of STS304-A1050-STS304 clad sheet was increased up to 4.4 at $150^{\circ}C$ that was 29% higher than at room temperature, whereas STS304-A1050-STS430 material was improved to 3.9 at $120^{\circ}C$ which was 15% better than at room temperature. In addition, comparison of wall thickness and hardness of a warm drawn cup with those of room temperature showed more even distributions. No separation between each laminated material after drawing occurred through inspection by microscope as well as application of penetrant test and bond strength test. Therefore, warm forming technique was confirmed to give better results in deep drawing of stainless clad sheet metal.

• Journal of the Korean Society for Heat Treatment
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• v.20 no.4
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• pp.181-186
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• 2007

Effect of heat treatment conditions on formability and property of warm hydroformed parts for Al 6061 extruded tubes was investigated in this study. For the investigation, as-extruded, fully annealed and T6-treated Al 6061 seamless tubes were prepared. To evaluate the warm hydroformability, uni-axial tensile test and free bulge test were performed at various pre- and post-heat treatment conditions. And the tensile test specimens were obtained from hexagonal prototype hydroformed parts at $250^{\circ}C$. As a result, hydroformability of fully annealed tube is 25% higher than that of extruded tube. The tensile strength and strain of hydroformed part reach to 330 MPa and 12%, respectively, when the part was T6 treated after warm hydroforming. However, the hydroformability of T6 pre-treated tube is relatively low due to the decreased elongation, 8%.

• Korean Journal of Childcare and Education
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• v.16 no.2
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• pp.161-178
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• 2020

Objective: The purpose of this study was to investigate the effects of parenting stress of mothers, warm parenting behaviors and controlling parenting behaviors on children's social competence. Methods: A total of 1515 mothers of young children(780 boys, 735 girls), who had participated in wave 7 of the Panel Study on Korean Children(PSKC), answered the questionnaires. The questionnaires included items about mothers' parenting stress, parenting behaviors, and their children's social competence. The collected data were analyzed using descriptive statistics, Pearson's correlation and structural equation models using SPSS 23 and AMOS 22. Results: First, there was a significantly negative correlation between mothers' parenting stress and children's social competence. Also, there was a significantly positive correlation between mothers' warm parenting behaviors and controlling parenting behavior and children's social competence. Second, mothers' parenting stress showed a direct negative effect on children's social competence. Third, mothers' warm parenting behaviors and controlling parenting behaviors showed partial mediating roles in the relationship between mothers' parenting stress and children's social competence. Conclusion/Implications: In order to develop positive social competence of children, programs and social support are needed to reduce mothers'parenting stress and induce positive parenting behaviors.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.2
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• pp.84-90
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• 2003

Magnesium alloys have been paid attention In automotive and industries as lightweight materials, and with these materials it has been attempted at deep drawing process for assessment of formability of sheet metal. For warm deep drawing process with a local heating and cooling technique, both die and blank holder were heated at warm temperature while the punch was kept at room temperature by cooling water. Warm deep-drawing process with considering heat transfer was simulated by finite element method to investigate the improvement of deep-drawability and temperature distribution of Mg alloy sheet. The effect of sham rate sensitivity index on the deformation profile was considered in this work and the simulation results revealed that considering heat transfer is very effective for deep-drawability of Mg alloy. The deformed blank In considering heat transfer was drawn successfully without any localized thinning and the cup height is higher in contrast to results of simulations in considering no heat transfer.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.02a
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• pp.136-143
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• 2002

Warm draw die technique which is one of the new forming technologies to improve formability of sheet metal is applied to the cylindrical and square cup drawing of stainless-aluminum clad sheets. In experiments the temperature of die and blank holder is varied from room temperature to $180^{\circ}C$, while the punch is cooled by circulation of coolant to increase the fracture strength of workpiece on the punch comer area. Test materials chosen for experiments are STS304-A1050-STS304 clad sheets. Teflon film as a lubricant is used on both sides of a workpiece. The limit drawing ratio and relative drawing depth as well as quality of drawn cups(distribution of thickness)are investigated and validity of warm drawing process is also discussed. No separation between each laminated material after drawing occurred through inspection by microscope as well as application of penetrant remover and bond strength test. Therefore, warm forming technique was confirmed to give better results in deep drawing of stainless clad sheet metal.

• Journal of Animal Environmental Science
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• v.1 no.1
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• pp.39-45
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• 1995

Temperatures of blood and skin, respiratory rate and plasma cortisol concentration in sheep at a warm (average ambient temperature of $15.3^{\circ}C$) and a hot (average ambient temperature of $27.0^{\circ}C$ environment were measured to investigate the effect of hot environment on the physiological responses in ruminant. Temperatures of core, mean skin and mean body in sheep were tended to increase at day time and to decrease at night time at both warm and hot environment, while 24-hr average for those temperatures were significantly higher at hot environment than at warm environment (P<0.05). The calculated body heat content was higher in sheep at hot environment than at warm environment (P<0.05). Respiratory rate and plasma cortisol concentration had no significant differences between warm and hot environment, suggesting that sheep were not stress by the hot environment in this experiment. It is, therefore, suggested that sheep were well adopted to hot environment by increasing body heat content against heat stress.

• Journal of Powder Materials
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• v.7 no.1
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• pp.42-49
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• 2000

Densificationbehavior of conventional austenitic stainless steel powder compacts was studied by comparing the relative density of sintered compact(Ds)with that of green compacts(Dg)prepared with various catbon contents and P/M process. Dg of 304and 316 powders by warm compaction under pressure of 686 MPa at heating temperature of powder(553K) and dies (573K) were 80% and 81%, repectively, whichwere 2 and 3% higher than those of conventional green compacts at the same pressure. Ds of 304 compacts sintered at 1373K in H2 gas has the same value of 84% max. regardless of compacting temperature, and Ds of 316 compacts at the same sintering conditions were 80% by conventional compaction and 83% by warm compaction. Oxygen contents of 304 and 316 sintered compacts were increased 1.43∼2.94% and 0.010∼0.921% higher than those of raw powders and warm green compacts, respectively. In other case, Ds of 316 compacts sintered at 1573K in vacuum had the same value of 86%max. And Ds of 316 compacts at the same sintering conditions were 83% and 86% by conventional and warm compaction, respectively. Oxygen contents of 304 sintered compacts were 0.321% and 0.360%, and in case of 316, they were 0.419% and 0.182% by the respective compating condition. With carbon additions in the range 0.1∼0.6% Ds increased to the extent of 86∼89% in 304 sintered compacts, and to 82∼84% and 85∼87% in 316 according to different two compacting peocesses compared to those of sintered compacts without carbon addition.

• Journal of Powder Materials
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• v.14 no.5
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• pp.298-302
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• 2007

In recent years, a rapid increase in demands for the soft magnetic composite parts has been created and it has been tried to improve their properties by various processing methods, alloying elements and compaction parameters. Warm compaction method has been used for the reduction of residual stress, the improvement of magnetic properties and the higher densities. In this work, the effects of warm compaction and polymer binder on magnetic properties of Fe powder core were investigated. The sintering powder, Fe oxide, was ball-milled for 30n hours. And then ball-milled Fe oxide powder was reduced through hydrogen reduction process. The hydrogen reduced Fe powder and polymer binder were mixed by 3-D turbular mixer. And then the mixed powder was warm-compacted. The magnetic properties such as core loss and permeability were measured by B-H curve analyzer.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.11
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• pp.1527-1576
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• 2002

Quick Response based Mass-Customization can be produced and distributed customized goods and services on mass basis in apparel e-business. Because consumers can: t touch and feel the apparel products in e-business, they tend to have the negative buying behavior. The purpose of this study is to investigate the differences of consumer's texture sensibility of apparel products based on marketing channels (on-line/off-line). Two types of questionnaires for on-line and of f-line were used to assess consumer sensibility on apparel fabric. The 8 swatches were selected in regard to the previous literatures. 205 questionnaires for each type (on-line/off-line) were distributed. Statistical devices were t-test, mean and standard deviation with SPSS10.0. The result of this study was showed that there were partially significant differences on consumers' texture sensibility on apparel products between on-line and off-line. Under on-line environment, consumers perceived corduroy as warm, strong, and sandy. taffeta as warm, sandy, and glossy, denim as sandy, and warm, organza as sandy, and thin, satin as sandy, dense, and modern, chiffon as sandy, and flat, velvet as warm, and soft, single jersey as warm, soft, and comfortable. Therefore, apparel firms cooperating based Mass-Customization in e-business have to pay attention to the differences on consumers’ texture sensibility of on-line apparel products from those of off-line.