이송 모듈을 사용한 리플로우 오븐의 열유동해석

정원중,권현구,조형희,Jeong, Won-Jung,Kwon, Hyun-Goo,Cho, Hyung-Hee 한국반도체디스플레이기술학회 2006 반도체디스플레이기술학회지 Vol.5 No.3

Because of new requirements related to the employment of SMT(Surface Mounting Technology) manufacturing and the diversity of components on high density PCB(Printed Circuit Boards), Thermal control of the reflow process is required in order to achieve acceptable yields and reliability of SMT assemblies. Accurate control of the temperature distribution during the reflow process is one of the major requirements, especially in lead-free assembly. This study has been performed for reflow process using the commercial CFD(Computational Fluid Dynamics) tool for predicting flow and temperature distributions. Porous plate was installed to prevent leakage flow which was one of the major problem of temperature uniformity in the reflow process. There is a separation region where the flow is turned. Outside wall made of porous plate is to prevent and minimize separation region for acquiring uniform temperature during operation. This paper provided design concept from CFD results of the steady state temperature distribution and flow field inside a reflow oven.

반도체 공정용 수직로 설계를 위한 열유동 제어

정원중(Won-Jung Jeong),권현구(Hyun-Goo Kwon),조형희(Hyung-Hee Cho) 한국유체기계학회 2006 유체기계 연구개발 발표회 논문집 Vol.- No.-

Because of new requirements related to the employment of SMT(Surface Mounting Technology) manufacturing and the diversity of components on high density PCB(printed circuit boards), Thermal control of the reflow process is required in oder to achieve acceptable yields and reliability of SMT assemblies. Accurate control of the temperature distribution during the reflow process is one of the major requirements, especially in lead-free assembly. This study has been performed for reflow process using the commercial CFD tool(Fluent) for predicting flow and temperature distributions. There was flow recirculation region that had a weak point in the temperature uniformity. Porous plate was installed to prevent and minimize flow recirculation region for acquiring uniform temperature in oven. This paper provided design concept from CFD results of the steady state temperature distribution and flow field inside a reflow oven.

Mandibular Posterior Crossbite Appliance 의 적용시 응력분포에 관한 광탄성법적 연구

정원중(Won Jung Jeong),김중한(Joong Han Kim) 조선대학교 구강생물학연구소 2001 Oral Biology Research (Oral Biol Res) Vol.25 No.1

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벤조디아제핀 급성 중독에서 발생하는 흡인성 폐렴 위험 인자

정원식 ( Won Sik Chung ),차경만 ( Kyung Man Cha ),김형민 ( Hyung Min Kim ),정원중 ( Won Jung Jeong ),소병학 ( Byung Hak So ) 대한임상독성학회 2016 대한임상독성학회지 Vol.14 No.1

Purpose: Aspiration pneumonia is an important complication of drug intoxication with decreased mental status. The purpose of the study is to investigate the risk factors of aspiration pneumonia in the patients of benzodiazepine overdose with or without co-ingestion of other drugs. Methods: A retrospective chart review of patients who visited the emergency department between January 2012 and December 2014 was conducted. Demographic data, time from ingestion to visit, initial vital signs, symptoms, mental status, medical history, laboratory results, chest radiological findings and co-ingested medications were recorded. Multiple logistic analyses were performed to verify the association between variables and the development of aspiration pneumonia. Results: A total of 249 patients presented to the emergency department with benzodiazepine overdose. Aspiration pneumonia had developed in 24 patients (9.6%). Univariate analysis revealed time from ingestion to visit was longer, Glasgow coma scale score was lower, hypoxia was presented, leukocytosis was shown, types of ingested drugs was high, less activated charcoal was applied and tricyclic antidepressants was taken in patients that developed aspiration pneumonia. Time from ingestion to visit (odds ratio (OR) 1.121, 95% confidence interval (CI), 1.057- 1.189, p=0.000), GCS score (OR 0.724. 95% CI, 0.624-0.839, p=0.000), oxygen saturation (OR 0.895, 95% CI, 0.835-0.959, p=0.002), and co-ingestion of TCA (OR 4.595, 95% CI, 1.169-18.063, p=0.029) were identified as risk factors of morbidity of aspiration pneumonia upon multiple logistic regression analysis. Conclusion: Time from ingestion to visit, low GCS score, low oxygen saturation and co-ingestion of TCA were risk factors of the development of aspiration pneumonia in benzodiazepine overdose patients.

고구마에서 ADP-Glucose Pyrophosphorylase Small Subunit cDNA의 Antisense 발현에 의한 전분생합성 저해

민성란,배정명,한지학,정원중,이영복,유장렬,Min, Sung-Ran,Bae, Jung-Myung,Harn, Chee-Hark,Jeong, Won-Joong,Lee, Young-Bok,Liu, Jang-Ryol 한국식물생명공학회 2007 식물생명공학회지 Vol.34 No.4

고구마 유래 ibAGP1, ibAGP2 유전자가 antisense 방향으로 각각 도입된 벡터를 섞어서 particle bombardment 방법으로 고구마 배발생 캘러스에 형질전환을 수행하였다. 선발배지에서 형성된 배발생 캘러스로부터 체세포 배발생 과정을 거쳐 식물체로 재분화된 개체에서 PCR과 Southern 분석으로 고구마의 염색체 게놈에 ibAGP1, ibAGP2 유전자가 도입되었음을 확인하였고, western blot을 통해 형질전환체의 AGPase small subunit 효소 생산이 전반적으로 대조구에 비해 감소하였다. 또한, 형질전환체의 잎과 괴근 절편체의 전분염색 결과에서도 대조구에 비해 부분적으로 전분염색이 이루어짐을 알 수 있었다. 특히, ibAGP1, ibAGP2 유전자가 동시에 들어 있는 식물체 잎에서는 ibAGP1만 들어있는 것에 비해 전분합성이 더욱 감소됨을 확인하였다. 고구마의 경우 감자를 비롯한 다른 식물들과는 달리 외형적인 생장자체를 심하게 저해하였으며 괴근이 형성되지 않아 ibAGP1, 2의 발현 여부가 식물체의 생장에 절대적인 영향을 미침을 시사한다. Embryogenic calluses derived from shoot apical meristem explants of sweetpotato were subjected to particle bombardment to generate transgenic plants for antisense expression of cDNAs encoding two different AGPase small subunit (ibAGP1 and ibAGP2). Plants were generated via somatic embryogenesis. PCR and Southern analysis demonstrated that the incorporation of ibAGP1 and ibAGP2 into the genome in an antisense orientation. Immunoblot analysis confirmed reduced levels of AGPase small subunit in transgenic plant leaves. Plants with both ibAGP1 and ibAGP2 produced a lower level of the protein than plants with ibAGP1 alone. iodine test demonstrated that transgenic plant leaves and storage root accumulated reduced amounts of starch. Iodine staining of leaf tissues indicated that transgenic plants accumulated less amount of starch than control. In accordance with western blot analysis, plants with both ibAGP1 and ibAGP2 accumulated a lower amount of starch than plants with ibAGP1 alone. Both transgenic plants exhibited a severely retarded growth, resulting in bare survival. It is suggested that disrupted expression of the gene encoding AGPase small subunit is lethal to the growth of sweetpotato contrast to other species including potato.

형질전환 토마토에서 Cytosine Methylation에 의한 유전자발현 억제

정서희,민성란,이수영,박지영,정화지,전재홍,유장렬,정원중,Jung, Seo-Hee,Min, Sung-Ran,Lee, Soo-Young,Park, Ji-Young,Davarpanah, S Javad,Chung, Hwa-Jee,Jeon, Jae-Heung,Liu, Jang-Ryol,Jeong, Won-Joong 한국식물생명공학회 2007 식물생명공학회지 Vol.34 No.4

토마토 형질전환체에서 NPTII 및 TPSP 유전자의 발현양상을 조사하였다. 4개 line 토마토 형질전환체가 선발배지에서 kanamycin에 저항성을 보이며 생산되었다. 그러나, 1번 line과 11번 line의 후대에서 NPTII 유전자의 발현이 억제되었으며, Kanamycin 저항성을 보이지 못했다. Southern 분석 결과, 1번 11번 line은 여러 copy의 외래 유전자를 가지고 있었으며, 2번, 10번 line은 1-2 copy의 외래유전자를 가지고 있었다. 형질전환 line 11번은 methylation sensitive 제한효소처리 후 DNA methylation 분석 결과, TPSP coding부위 및 도입유전자의 발현을 조절하는 CaMV35S 프로모터 주위에서 CpG methylation이 축적되었음이 확인되었다. 따라서 여러 copy의 외래유전자를 가진 토마토 형질전환 line 11번에서 NPTII 유전자 및 TPSP유전자의 발현이 억제된 것은 transcriptional gene silencing 기작에 의한 것으로 추정되었다. Transgene expression was analyzed in tomato plants. Four lines of neomycin phosphotransferase II gene (NPTII) and the trehalose biosynthetic fusion gene (TPSP) transformed $T_0$ plants showed kanamycin resistance on selection medium. However, the analysis of phenotype (kanamycin resistance) and mRNA expression in $T_1$ plants indicated that the expression of the NPTII and TPSP transgenes was down-regulated to an undetectable level in two independent lines 1 and 11. Southern analysis demonstrated that the lines 1 and 11 had multicopies of the transgenes, whereas the typical transgenic lines 2 and 10 had 1 or 2 copies. DNA methylation analysis using methylation sensitive enzyme detected accumulated CpG DNA methylation on TPSP coding region and CaMV35S promoter region in the line 11, but not the typical transgenic line 2. These results suggest that multicopy transgene in plants is attributed to down-regulation of the transgene expression via transcriptional gene silencing.

응급실에 내원한 소아 전기 화상 환자의 임상적 양상과 예방을 위한 노출 요인 분석

박상준 ( Sang Jun Park ),김성욱 ( Sung Wook Kim ),정원중 ( Won Jung Jeong ),오상훈 ( Sang Hoon Oh ),박정택 ( Jeong Taek Park ) 대한외상학회 2015 大韓外傷學會誌 Vol.28 No.3

Purpose: The aims of this study were to discuss treatment and prevention under the age of 18 to identify the characteristics of the electrical burn patients. Methods: We retrospectively reviewed medical records of 97 patients with under age 18 of electric burn who were treated in emergency department of quarterly over 10,000 targets within the desired hospital for evaluation of electrical injuries between January 1, 2009 and December, 2013. We investigated age, gender, injury mechanism, season, degree of burn, surface of burn, complication, blood test, and voltage, kind of current. Results: Of the patients, 50 (50.5%) patients were in the first degree burn and 47 (49.5%) patients were in second degree burn. 68 (70.1%) patients had electric burn at home. 75 (85.2%) of 88 patients had normal sinus rhythm and other 13 people showed a RBBB, VPC, sinus bradycardia, sinus tachycardia. 41 (42.3) of 97 patients were in infants and 26 (26.8%) patients were in adolescence. Conclusion: The results of this study emphasize the need for prevention of electricity at home for childhood and education of the adolescence. [ J Trauma Inj 2015; 28: 170-176 ]

의도적 음독으로 응급실에 내원한 소아 청소년 환자들의 성별에 따른 특성 분석

김윤재 ( Yun Jae Kim ),소병학 ( Byung Hak So ),김형민 ( Hyung Min Kim ),정원중 ( Won Jung Jeong ),차경만 ( Kyeong Man Cha ),김성욱 ( Seong Wook Kim ) 대한임상독성학회 2014 대한임상독성학회지 Vol.12 No.2

Purpose: The aim of this study is to investigate the difference between male and female in some clinically meaningful aspects and to prevent intentional poisoning in children and adolescents. Methods: Retrograde medical records review of patients who visited the emergency department of two secondary hospitals for drug ingestion from March 2010 through March 2013 was performed. Unintentional ingestion or ingestion by others was excluded. Results: A total of 138 cases were reported, male 25.4% (n=35), female 74.6% (n=103). The reason for poisoning was intentional in 132 cases (95.7%) and misuse in six cases (4.3%). In female patients, non-prescription drugs was the most common cause of intentional poisoning (68.9%). Male patients tend to use life substances for intentional poisoning more frequently (20.0%) than female (3.9%). Seven male patients and 12 female patients had previous psychiatric history and 34.3% of male and 41.7% of female were consulted to the psychiatric department. Conclusion: Female adolescents are more likely to ingest drugs intentionally for suicide attempt than males of comparable ages. The drugs they ingested were, in many cases, obtained with ease from the drug store nearby and, remarkably, most of the drugs they obtained in that way were acetaminophen-containing. This suggests that some guidelines or control in the pharmacy that restrict children or adolescents from obtaining potentially or possibly life-threatening drugs might be necessary. In addition, education regarding drugs is thought to be necessary in school for teenagers as they tend to misuse them with incorrect acknowledgement.

외상 환자의 중증도 판단과 예후 예측을 위한 개별 인자들의 유용성 평가

김성윤 ( Sung Yoon Kim ),소병학 ( Byung Hak So ),김형민 ( Hyung Min Kim ),정원중 ( Won Jung Jeong ),차경만 ( Kyung Man Cha ),최승필 ( Seung Pill Choi ) 대한외상학회 2015 大韓外傷學會誌 Vol.28 No.3

Purpose: Many patients are injured by trauma. And some of them expire due to severity of trauma. Various scoring systems have been introduced in grading severity and predicting mortality of trauma patients. This study is to evaluation the usefulness of factors for determining the severity and predicting the prognosis of the trauma victims. Methods: Data on the patients who visited our Emergency departments from January 2010 to December 2011 were retrospectively reviewed using electronic medical records. The patients were activated severe trauma team calling system. The patients were categorized as survivors and non-survivors. Univariated associations were calculated, and a multiple logistic regression analysis was used to determine variables associated with hospital mortality. Results: Two hundred sixty two(262) patients were enrolled, and the mortality rate was 25.6%. By multivariate analysis, lower respiration rate, lower Glasgow Coma Score, higher International Normalized Ratio and emergency transfusion within 6 hours were expected as severity and prognosis predict factors (each of odds ratio were 24.907, 14.282, 2.667 and 16.144). Conclusion: As predict factors, respiration rate, Glasgow Coma Score, International Normalized Ratio and emergency transfusion, are useful determining the severity and predicting prognosis of trauma victims. [ J Trauma Inj 2015; 28: 134-143 ]

의식 저하로 내원한 중독 환자들에 대한 호기말 이산화탄소분압 관찰의 효과

권용희 ( Yong Hee Kwon ),소병학 ( Byung Hak So ),정원중 ( Won Jung Jeong ) 대한임상독성학회 2021 대한임상독성학회지 Vol.19 No.1

Purpose: This study aimed to analyse the effect of End-Tidal Carbon Dioxide (ETCO2) monitoring on patients who had been poisoned and presented in the emergency department with decreased consciousness. Methods: The data of patients over 18 years old presenting with poisoning from 2016 to 2020 was collected from the emergency department. We retrospectively analyzed their medical records, and defined patients with a Glasgow Coma Scale (GCS) score of 9 or less as having decreased consciousness. We divided the patients into two groups, one with ETCO2 monitoring and the other without, and the difference between the two groups was compared. Results: 168 patients participated in this study and 83 (49.4%) of them belonged to the ETCO2 monitoring group. In this group, the interval between arterial blood tests was statistically significantly longer and the rate of intubation was lower. In addition, in the monitoring group, the incidence of pneumonia and the rate of poor prognosis was not significantly higher. Conclusion: Although ETCO2 monitoring does not directly affect the prognosis of poisoned patients with decreased consciousness, it should be actively done as it can help to adequately treat patients while avoiding invasive techniques or unnecessary intubation.