• 한국정밀공학회지
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• 제23권1호
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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.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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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-$HT^{TM}$.

• Clinical Endoscopy
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• 제55권1호
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• pp.15-21
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• 2022

Endoscopic submucosal dissection (ESD) is the standard treatment method for esophageal, gastric, and colorectal cancers. However, it has not been standardized for duodenal lesions because of its high complication rates. Recently, minimally invasive and simple methods such as cold snare polypectomy and underwater endoscopic mucosal resection have been utilized more for superficial nonampullary duodenal epithelial tumors (SNADETs). Although the rate of complications associated with duodenal ESD has been gradually decreasing because of technical advancements, performing ESD for all SNADETs is unnecessary. As such, the appropriate treatment plan for SNADETs should be chosen according to the lesion type, patient condition, and endoscopist's skill.

• 한국작물학회지
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• 제41권2호
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• pp.139-144
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• 1996

발아후 일주일간 생육한 보리 유식물체를 이용하여 혐기처리, 저온처리 및 기계적 상처에 대한 보리 식물체의 반응양상을 유리아미노산과 유리당 함량의 변화를 분석하여 조사하였다. 혐기적처리에 반응하여 함량의 변화가 뚜렸하게 나타나는 아미노산은 alanine, GABA, glutamic acid였다. Alanlne과 GABA함량은 10시간까지의 혐기처리에 의해 급속히 증가하였으나 glutamic acid 함량은 크게 감소하는 경향을 나타내었다. 상처에 의한 alanine, GABA, glutamic acid반응 양상은 혐기처리와 유사하였으나, 함량변화 정도는 혐기처리에서 보다 훨씬 낮았다. 저온처리에 의하여 지상부와 뿌리 중의 GABA 함량이 증가하였다. 혐기적 처리에 의하여 지상부의 유리당함량이 변화하였으며, glucose나 fructose보다는 sucrose의 함량변화가 상대적으로 크게 나타났다

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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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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• 제33권12호
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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.

• 한국산학기술학회논문지
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• 제9권6호
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• pp.1882-1888
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• 2008

1-MCP(1-methylcyclopropene) 처리에 의한 오이 'Baekdadaki'의 수확 후 품질에 관한 연구를 수행하였다. 1-MCP의 농도별 250ppb, 500ppb, 1,000ppb 처리 후 상온과 저온($10^{\circ}C$)으로 나누어 저장하면서 생리적 특성변화 및 호흡율, 에틸렌 발생율을 조사하였다. 물리화학적 특성변화로 생체중과 경도는 상온, 저온 모두 저장 중 감소하였고 1-MCP 처리중에는 저온의 500ppb 에서 가장 적은 감소율을 보였다. 노화의 지표인 과피 b값은 상온괴 저온 모두 1-MCP 250, 1,000ppb에서 가장 높은 증가율을 보였고 저온저장 15일째에 황화와 함께 과실 무름 현상이 나타났다. 오이의 저온저장 15일 동안 1-MCP 500ppb 처리에서 가장 낮은 부패율을 나타내어 상품성을 상대적으로 높게 유지하였다. 호흡율은 1-MCP 250ppb 처리에서 높은 증가율을 보였고, 에틸렌 발생량은 상온 저장된 1,000ppb 에서 저장 6일 동안 가장 높은 증가율을 보였다. 오이 'Baekdadaki' 품종의 수확 후 품질은 1-MCP 500ppb 농도에서 가장 좋은 품질을 유지하였고 여러 농도의 1-MCP 처리에서 에틸렌 생성이 억제되지는 않았다.

• 사상체질의학회지
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• 제36권1호
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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.

• 한국정보통신학회논문지
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• 제10권7호
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• pp.1301-1306
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• 2006

알루미늄 합금은 자동차부품 및 전자부품산업 개발에 크게 기여하고 있는 소재로서, 제조방법 중 냉？온간 단조 공법에 의해 제조하는 것이 대량 생산되어지는 자동차 및 전자산업부품개발에 있어서 매우 효율적이다. 따라서, 본 연구에서는 차세대 콤프레샤 실린더 블록 개발을 위하여,AI소재 (AI-Mg-Si계합금)를 활용, 냉 -온간 단조법을 이용 하여 개발하고자 한다. 이를 위해, 제조 시편의 미세조직 및 기계적 성질을 조사하였는데,미세조직은 공정형으로 구성되었으며, $Mg_2Si$의 중간상이 석출되었다. 그리고 인장강도는 291.7MPa 로 나타났으며, 그러한 결과를 바탕으 로 차세대 콤프레샤 실린더 블록시제품을 제작하였다.

• 대한한방체열의학회지
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• 제7권1호
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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.