• Journal of the Korean Society for Precision Engineering
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• v.23 no.1 s.178
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• pp.185-192
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• 2006

A manufacturing process for a clutch gear which demands high strength and wear resistance, was developed by means of computer simulation. A preform was made by hot forging process and subsequent cold sizing process is applied to complete precise tooth part. Processes to obtain high dimensional accuracy and superior mechanical properties are analyzed and optimal heat treatment cycle to improve cold forgeability is introduced. Prototype was produced and the dimensional accuracy of the prototype was inspected to verify proposed process.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.129-134
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• 2009

The dimension of forged part is different from that of die. Therefore, a more precise die dimension is necessarys to produce the precise part, considering the dimensional changes from forging die to final part. In this paper, both experimental and FEM analysis are performed to investigate the effect of several features including die dimension at each forging step and heat-treatment on final part accuracy in the closed-die upsetting. The dimension of forged part is checked at each stage as machined die, cold forged, and post-heat-treatment steps. The elastic characteristics and thermal influences on forging stage are analyzed numerically by the DEFORM-$2D^{TM}$. The effect of residual stress after heat-treatment on forged part could be considered successfully by using DEFOAM-$HT^{TM}$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.139-144
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• 1996

Effects of anaerobic, mechenical wounding and cold treatments on free amino acid and free sugar contents were examined in 7 day-old barley seedlings. In barley shoots under anaerobic condition, drastic changes in free amino acid content were observed. Alanine, ${\gamma}$-aminobutyric aicd(GABA) and glutamic acid contents changed most prominantly. Alanine and GABA contents increased rapidly with incubation time up to 10 hr. Glutamic acid content, however, decreased drastically during the first 5 hr of incubation, then increased thereafter. Barley shoots showed similar but smaller changes in amino aicd contents in response to mechanical wounding. GABA content increased in shoots and roots in response to the cold treatment. But increase in GABA content was greater in anaerobic than cold treatment. In anaerobically treated shoots, changes in free sugar content were less prominant than those in amino acid content. Sucrose content changed relatively larger than glucose and fructose contents in excised shoots.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.100-100
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• 2018

Zoysia japonica Steud.(Zj) is a typical warm-season Korean lawn grass, which is used in many places such as river banks, roadside and soccer fields in Korea. Recently, it has also been used in school yards and the Saemangeum reclaimed land to reduce water pollution. Although the cultivated area of turfgrass is steadily increasing worldwide, it grows fast requiring frequent mowing and is difficult to grow in shady areas and the cold region. Therefore this study aims searching for useful gene(s) to develop abiotic stress tolerant and dwarf zoysiagrass. We isolated Ycf4 gene based on the sequence from Oryza sativa Japonica through RT-PCR and RACE PCR. Ultimately, open reading frame (ORF) of ZjYcf4 was 558bp long, encoding a protein of 186 amino acid residues. NCBI blast results showed that the ZjYcf4 protein is evolutionarily closely related to Ycf4 protein from Zoysia macrantha and Setaria italica (100% and 98%, respectively). To determine whether ZjYcf4 was involved in environmental stress in wild-type zoysiagrass, expression patterns of the gene were analyzed by real-time PCR under salt, cold and dark conditions. They were analyzed after each stress treatment for 3 hours. In salt and cold stresses, the expression was higher compared to control (3-fold and 1.5-fold, respectively), although there was a 1.6-fold decrease in expression under dark stress treatment. As reported previously, we suggest that ZjYcf4 gene affects abiotic stress such as salt, cold and dark.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.12
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• pp.2031-2038
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• 2020

Objective: This study aimed to determine the effect of intermittent feeding and cold water on performance and carcass traits in broiler chickens between 4 to 6 wk of age exposed to daily high temperature. Methods: Broilers were assigned to four treatment groups according to a 2×2 factorial design between 22 to 42 d of age (80 broilers per treatment, 4 replications). Broilers were divided into two main groups as feeding type (ad-libitum [AL] and intermittent [IF] for 6 h daily) and sub-groups as water temperature (normal [NW], 24.9℃ and cold [CW], 16.4℃). Heat treatment was applied between 11.00 to 17.00 h daily between 22 to 42 d of age. Results: Live weight at 6th wk was not affected by feeding type and water temperature, but the live weight was significantly higher in IF chickens at the 5th wk (p<0.05). Average weekly gain of IF broiler chickens were higher compared to AL group at 4, 5, and 6 wk of age (p< 0.05). Although feeding type did not affect feed intake in 4 and 5th wk, feed intake was higher in IF chickens at 6th wk (p<0.01). In addition, feeding type and water temperature did not affect feed conversion ratio and interactions were not significant (p>0.05). Water temperature had no significant effect on heart, liver, gizzard, and abdominal fat percentages (p>0.05). Conclusion: It is concluded that IF increased the average weekly gain in chickens reared under daily heat stress for 6 h between 22 to 42 d of age. IF in hot environmental conditions slightly increased performance without adversely affecting health, welfare, and physiological traits, whereas CW implementation had no significant effect on performance. It can also be said that IF suppresses a sudden increase in body temperature depending on age and live weight.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1882-1888
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• 2008

Effects of 1-MCP(1-methylcyclopropene) on the postharvest life and fruit quality of cucumber 'Baekdadaki' were investigated. Cucumber were held at room and cold chamber($10^{\circ}C$) treated with several concentrations of 1-MCP. Physico-chemical characteristics such as fresh weight and firmness were greatly varied during storage, and the treatment with I-MCP(500ppb) showed the minimal loss of the values at harvest. The peel b value representing a senescence process was higher investigated in 1-MCP(250 and 1,000ppb treatment, and led to the apparent yellowing and softening after cold storage for 15 days. 1-MCP(500ppb) showed lower decay rate and better marketability of cucumber than other treatments after cold storage for 15 days. The respiration rate was higher found in cucumber treated with 1-MCP(250ppb) than in other treatment. Ethylene evolution was most detected in cucumber treated with 1-MCP(1000ppb) after room storage for 6 days. 1-MCP did not affect the production of ethylene in cucumber during room and cold storage.

• Journal of Sasang Constitutional Medicine
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• v.36 no.1
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• pp.31-42
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• 2024

Introduction This case series report an attempt to treat Sasang constitutional medicine on Soyangin patients with unspecified hot flush. Methods The patients in this case were diagnosed as Soyangin cold pattern and treated with herb medicine Dojeokgangi-tang. Treatment outcome was monitored retrospectively. Results Persistent hot flush significantly improved to normal levels in all 3 Soyangin patients, and 2 out of 3 showed the effect within 4 weeks, those with more chronic symptoms required more time. Discussion This study suggests the significance of Sasang constitutional medicine treatment in Soyangin patients with Hot flush. Additionally, the characteristics of patients with hot flush presented in this study were verified as meaningful diagnostics indicator of Soyangin lesser yang wind damage. Furthermore, it emphasizes the value of original symptoms as a standard for evaluating treatment effectiveness.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.7
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• pp.1301-1306
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• 2006

Aluminum alloys are gaining increased acceptance in the automotive and electronic industeries and cold & hot forging is the most efficient method of manufacturing such mass produced parts. This study has been investigated the microstructures and mechanical properties of A6061(Al-1.2Mg-0.8Si) alloy fabricated by cold & hot forging process for development of the future compressor block. The microstructure of cold & hot forginged specimen were composed of eutectic structure aluminum solid solution and $Mg_2Si$ precipitates. The tensile strength of as-solid solution treatment A6061 alloy revealed 291.7MPa. It was fabricated that a trial future compressor cylinder block using cold & hot forging.

• Journal of Oriental Medical Thermology
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• v.7 no.1
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• pp.22-29
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• 2009

Purpose: This study intends to report the effects of Koong Gui Tang on Cold Hypersensitivity caused by acute and chronic Blood Deficiency. Methods: The patients having Cold Hypersensitivity were treated with oriental medicine including herbal medication therapy. Thereafter their health status was analyzed with their own empirical assessments and VAS. Results: After the series of medical treatment, Cold Hypersensitivity caused by acute and chronic Blood Deficiency has shown considerable improvement. Conclusion: This case study shows that Koong Gui Tang therapies are medically effective on Cold Hypersensitivity caused by acute and chronic Blood Deficiency.

• Transactions of Materials Processing
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• v.22 no.3
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• pp.158-164
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• 2013

The spheroidization behavior of cementite in a SK85 high carbon steel was investigated in this study. Fine and coarse pearlite microstructures were obtained by appropriate heat treatments according to the TTT diagram of SK85 high carbon steel. Hot rolled plates of SK85 steel were austenitized at $800^{\circ}C$ for 2 hrs and then put directly into a salt bath at either $570^{\circ}C$ or $670^{\circ}C$ to obtain a fine pearlite (FP) structure and a coarse pearlite (CP) structure, respectively. Cold rolling was subsequently conducted on those specimens with reduction ratios from 0.2 to 0.4. Spheroidization heat treatments were conducted at the subcritical temperatures of 600 and $720^{\circ}C$ for 1 to 32 hrs to elucidate the effect of initial microstructures, heat treatment temperature, and cold reduction ratios on the cementite spheroidization rate. Spheroidization proceeded with fragmentation of cementite plates, spheroidization of the cementite platelets, and coarsening consecutively. Mechanical fragmentation of cementite by cold rolling expedited the rate of spheroidization. The spheroidization rate of FP was much more rapid than that of CP and the spheriodization rate increased with increases in the cold reduction ratio.