극저온 열처리 공정이 6061 알루미늄 합금의 잔류응력과 인장특성에 미치는 영향

박기정 ( Ki Jung Park ),고대훈 ( Dea Hoon Ko ),김병민 ( Byung Min Kim ),임학진 ( Hak Jin Lim ),이정민 ( Jung Min Lee ),조영래 ( Young Rae Cho ) 대한금속재료학회(구 대한금속학회) 2011 대한금속·재료학회지 Vol.49 No.1

To develop a 6061 aluminum alloy with low residual stress and high tensile strength, a cryogenic treatment process was investigated. Compared to the conventional heat treatment process for precipitation hardening with artificial aging, the cryogenic treatment process has two additional steps. The first step is cryogenic quenching of the sample into liquid nitrogen, the second step is up-hill quenching of the sample into boiling water. The residual stress for the sample was measured by the sin2 ψ method with X-ray diffraction. The 6061 aluminum alloy sample showed 67% relief in stress at the cryogenic treatment process with artificial aging at 175℃. From this study, it was found that the optimum cryogenic treatment process for a sample with low residual stress and high tensile strength is relatively low cooling speed in the cryogenic quenching step and a very high heating speed in the up-hill quenching step.

호접란 대량번식시 탈지면의 갈변고사 억제효과

박명주(Myung-Joo Park),임륜경(Ryun-Kyoung Lim),박순정(Soon-Jung Park),김두환(Doo-Hwan Kim) 한국원예학회 1997 한국원예학회 학술발표요지 Vol.15 No.2

CIGS 박막 태양전지의 ZnS 버퍼층 증착 시 구연산나트륨 첨가에 따른 박막의 특성 분석

박소망(So Mang Park),박정은(Jeong Eun Park),박정훈(Jung Hoon Park),Jackson Bweupe,임동건(Donggun Lim) 한국태양에너지학회 2018 한국태양에너지학회 학술대회논문집 Vol.2018 No.11

평활관과 낮은 핀관에서 R245fa의 풀 비등 열전달계수

박기정(Ki-Jung Park),이요한(Yohan Lee),임병덕(Byeongdeok Lim),정동수(Dongsoo Jung) 대한설비공학회 2011 설비공학 논문집 Vol.23 No.3

In this work, pool boiling heat transfer coefficients(HTCs) of R22, R123, R134a, and R245fa are measured on both horizontal plain and 26 fpi low fin tubes. The pool boiling temperature is maintained at 7℃ and heat flux is varied from 80 ㎾/㎡ to 10 ㎾/㎡ with an interval of 10 ㎾/㎡. Wall temperatures are measured directly by thermocouples inserted through holes of 0.5 ㎜ diameter. Test results show that HTCs of high vapor pressure refrigerants are usually higher than those of low pressure fluids in both plain and low fin tubes. On a plain tube, HTCs of R245fa are 23.3% higher than those of R123 while on a 26 fpi low fin tube, HTCs of R245fa are 46.3% higher than those of R123. The fin effect is more prominent with low vapor pressure refrigerants than with high vapor pressure ones due to a sweeping effect.

폐암의 표지자로써 Cyfra 21 - 1 의 유용성

박현덕(Hyun Duk Park),정현식(Hyun Sik Jeong),박정식(Jeung Sik Park),임성호(Sung Ho Lim),이은정(Eun Jung Lee),윤중원(Jung Won Yun),정수석(Su Suk Jung),신호철(Ho Cheol Shin),이승세(Seung Sei Lee) 대한내과학회 2002 대한내과학회지 Vol.62 No.4

목적 : 폐암에 대한 종양표지자로서는 암태아성 항원 (CEA), 편평세포암 항원 (SCC Ag), 신경원 특이성 에놀라제 (NSE) 등이 있으나 Cyfra 21-1은 최근에 발견된 종양표지자로서 비소세포성 폐암에 민감도가 우수한 것으로 보고되고 있다. 본 연구에서는 폐암에서 Cyfra 21-1의 민감도를 알아보고 폐암의 병기와의 관계를 알아 보았다. 대상과 방법 : 환자는 강북삼성병원에 입원하여 조직학적 및 세포병리검사상 확진된 폐암환자 110명을 대상으로 연구하였고 환자의 혈청에서 CEA, SCC Ag, NSE, Cyfra 21-1을 측정하였다. 결과 : 전체 폐암 환자에서 종양표지자의 민감도는 Cyfra 21-1이 51.8%였다. Cyfra 21-1의 양성율은 선암에서 63.2%, 편평세포암에서 54.1%, 소세포암에서 40.0%였고, 소세포암에 비해 선암과 편평세포암에서 통계학적으로 유의하게 (p<0.05) 높게 측정되었다. 병기에 따른 Cyfra 21-1의 민감도는 다른 종양표지자보다 양성율이 높고 T 병기가 진행하면서 높아지는 경향이 있었지만 통계적인 유의성은 없었고 림프절의 전이와 타장기로의 전이 유무에 따른 Cyfra 21-1의 양성율도 통계적으로 유의한 차이는 없었다. 선암과 편평세포암에서 병기에 따른 Cyfra 21-1의 평균치는 병소의 크기가 증가함에 따라 증가하지만 통계적인 유의성이 없었고 림프절 침범과 타장기로의 전이 유무에 따른 Cyfra 21-1의 농도의 변화도 통계적으로 유의한 차이는 없었다. 결론 : 본 연구에서 Cyfra 21-1은 폐암에서 기존의 종양표지자와 비교해 볼 때 상대적으로 가장 높은 양성율을 보이며 특히 비세포암에서 선별검사시 기존의 종양표지자와 함께 사용하면 더욱 유용하게 사용할 수 있다. 종양의 크기에 따라서 Cyfra 21-1 측정치도 증가하는 경향을 보이지만 통계적인 유의성은 없었고 조직학적인 아형에 따라서는 선암의 경우가 편평세포암의 경우보다 높게 나와 다른 기관의 연구와 상의한 결과를 보였다. Background : Cytokeratins are epithelial markers whose expressions are not lost during malignant transformation. The utility of cytokeratin fragment (Cyfra) 21-1, a new tumor marker, was investigated in 110 patients with lung cancer. The aims of this study were to confirm sensitivity of Cyfra 21-1 in detecting non-small cell cancer, to assess the potential relationship between Cyfra 21-1 and disease stage of the lung cancer. Methods : We measured serum levels of four tumor marker (NSE, CEA, SCC Ag, Cyfra 21-1) in 110 patients with lung cancer. The measurement of serum level of Cyfra 21-1 was performed with a cut off value of 3.3 ng/mL. An immunoradiometric assay was used to detect a fragment of the cytokeratin 19. The patients were grouped according to the stage of the disease and tumor type. Results : Overall sensitivity of Cyfra 21-1 was relatively high (51.8%) than others tumor markers. Sensitivity of this marker was especially high for adenocarcinoma (63.2%) and squamous cell carcinoma (54.1%). In contrast, sensitiviy of Cyfra 21-1 was relatively low for small cell lung carcinoma (40.0%). Serum levels of Cyfra 21-1 were higher in advanced nonsmall cell lung cancer than early stage disease. Conclusion : We conclude that Cyfra 21-1 is a sensitive tumor marker of nonsmall cell lung cancer, especially adenocarcinoma and also may be a useful adjunctive marker for disease monitoring.(Korean J Med 62:415-421, 2002)

공개공지효용성제고(公開空地效用性提高)를 위한 설계지침개선방안(設計指針改善方案)

박정임 ( Jung Lim Park ),김현준 ( Hyun Jun Kim ),권영휴 ( Young Hyoo Kwon ) 한국환경복원기술학회 2011 한국환경복원기술학회지 Vol.14 No.3

In urban space, public space is publicly or privately owned space freely accessible by the public. Privately owned public space to the public hosts small-scale rest facilities to serve the public in buildings of certain purposes and sizes for the sake of pleasant urban environment. The Building Act and building ordinances formulate a set of criteria for management and easement of construction standards as well as the area. When creating privately owned public space, one can get incentives through the easement of floor space index and height limit. The purposes of this study were to investigate and analyze privately owned public open space, which is freely accessible by the public, and its adjacent streets and to propose plans to improve the regulations for securing privately owned public space for more rational and practical legal applications. The study then proposed some plans to help to increase the quality of privately owned public space including applying the coefficient to suggest the type of privately owned public space fit for the features of the streets and measure the appropriate utility level differently and distinguishing the mandatory items according to the facility regulations in privately owned public space from the ones qualified for additional points in case of installation. The types of privately owned public open space should be applied differently and the content of facilities intended should be different according to whether it will serve as a resting place or grant more importance on traffic by walking, depending on the features of its adjacent streets. The privately owned public space, the frontage space of building, and the adjacent sidewalks should become a whole and be regarded as one space from the integrated perspective. The results of the study claim further significance in that it investigated privately owned open space and roadside across Seoul. They will serve as useful data to solve the problems with the privately owned public space of the city, which destroys spatial continuity by focusing on the quantitative increase of privately owned open space and creating individual privately owned open spaces and builds high-rise buildings alienated from the existing spaces, and to increase the quality of future privately owned public space.

기니 픽 회장 운동 기능에 미치는 Phosphodiesterase 4 형과 5 형 억제제의 효과

박효진(Hyo Jin Park),최성우(Sung Woo Choi),이영호(Yong Ho Lee),임정현(Jung Hyun Lim),이상인(Sang In Lee),박인서(In Suh Park) 대한소화기학회 2002 대한소화기학회지 Vol.39 No.5

Background/Aims: Intracellular cAMP or cGMP is degraded by cyclic nucleotide phosphodiesterase ( PDE) . We hypothesized that PDE inhibitors modulate the peristalsis and nerve- induced responses of the smooth muscle of the guinea pig ileum. Methods: To examine the effect of rolipram ( type 4 inhibitor of PDE) and zaprinast ( type 5 inhibitor of PDE) , we measured peristaltic amplitude, area under curve ( AUC) , and frequency of contractions from ileal preparation using the peristaltic bath. The mechanical activity of the circular muscle was measured with a clip attached, via the three sites of serosal surface, to the underlying circular muscle of intact ileum in the peristaltic chamber. In another set of experiment, muscle strips from the ileum were stimulated by an electrical field. The effects of rolipram, and zaprinast, on peristalsis and nerve- induced contraction were explored. Results: The amplitude and AUC of peristaltic contractions were significantly decreased in rolipram or zaprinast-treated group and frequency of contractions was significantly delayed in rolipram or zaprinast-treated group. The nerve- induced contraction of smooth muscle was significantly decreased in rolipram-treated group. Conclusions: These observations suggest that PDEs may play a role in the modulation of peristaltic behavior of the ileum and PDE inhibitors may be used in the treatment of hyperkinetic bowel disorders. ( Korean J Gastroenterol 2002; 39: 343- 349)

PSTN 서비스 특성을 이용한 ISDN의 트래픽 특성 분석 및 트래픽 예측

박정한(Jung-Han Park),이치영(Chi-Young Lee),김미선(Mi-Seon Kim),심택수(Taek-Su Shim),조영주(Young-Ju Cho),이동섭(Dong-Seop Lee),이주영(Joo-Young Lee),박창욱(Chang-Wouk Park),김영우(Young-Oo Kim),임인칠(In-Chil Lim) 대한전자공학회 1994 대한전자공학회 학술대회 Vol.1994 No.7

탄약고 폭발 사고로 기인한 환경영향권 검토에 관한 연구

박정봉(Jung Bong Park),조상호(Sang Ho Cho),박훈(Hoon Park),임대규(Dae Gyu Lim),신영철(Young Cheol Shin) 한국방재안전학회 2016 한국방재안전학회 학술대회 논문집 Vol.2016 No.-

대량의 고성능 폭약 및 폭탄이 저장된 저장소(이하 탄약고)는 예기치 않은 폭발사고가 인접한 보안물건에 미치는 피해를 최소화하기 위하여 다양한 안전장치를 구비하고, 일정 안전거리를 확보하도록 법으로 규제하고 있다. 국내의 경우, 탄약고의 폭발사고로부터 발생할 수 있는 지반진동 및 폭풍압 등과 같은 환경 피해에 대한 정량적인 평가 및 3차원 예측 시뮬레이션 관련 연구결과가 극히 제한적으로 공개되어 있어 현행 관련 법규에서 제시된 규제내용의 적합성 여부를 판단하기 어렵다. 이에 따라 본 연구는 탄약고 내 일정 정체량의 폭약이 폭발 시 발생될 수 있는 환경 영향적인 요소를 정량적으로 평가하는데 그 목적이 있다. The storage structure of large amount of high explosives and bombs (hereinafter referred to as ammunition ) is regulated by law to ensure a safety distance which minimizes the environmental damage by unexpected explosions in the storage. In Korea, there are a few case studies on quantitative evaluation and 3 dimensional simulation of environmental damages by explosion induced ground motion and air blast from explosion accident in ammunition storage. The purpose of this study is to quantitatively evaluate the environmental impacts caused by explosives accident in the ammunition.

생산지 수집 신선 유기농 농산물 미생물 분포도 분석

박원정(Won-Jung Park),류화연(Hwa-Yeon Ryu),임가연(Ga-Yeon Lim),이영덕(Young-Duck Lee),박종현(Jong-Hyun Park) 한국식품과학회 2014 한국식품과학회지 Vol.46 No.2

신선편이식품 소재인 유기농산물의 미생물 분포와 품질을 평가하기 위해서 풋고추, 상추, 토마토, 사과, 배, 쌀 등의 농산물을 47개 지역에서 관행농 농산물과 동시에 현장에서 시료를 수집하였다. 일반 세균수로는 유기농 고추가 평균 4.07 log CFU/g, 관행농 고추는 3.71 log CFU/g 검출되었고 상추는 유기농, 관행농에서 6.76-6.90 log CFU/g로 분석되었다. 토마토와 사과는 2종류 시료에서 각각 2.08-2.92 log CFU/g, 0.70-0.82 log CFU/g로 검출되었다. 쌀도 유기농과 관행농 시료에서 2.92-2.98 log CFU/g 범위의 세균분포를 보여주었으나 유기농 배에서는 4.48 log CFU/g, 관행농 배는 2.84 log CFU/g의 분포도를 보여 주었다. 분석시료에 따라 미생물의 분포에 많은 차이를 보여 주었으며 유기농과 관행농산물의 미생물분포는 거의 차이가 없었다. 병원성 세균인 Cl. perfringens, E. coli O157:H7, L. monocytogenes, Salmonella, S. aureus은 전혀 검출되지 않았다. 그러나 유기농산물 2개(4%)와 관행농산물 3개(6%)에서 E. coil가 1.7 log CFU/g으로 검출되었고 B. cereus는 유기농 6개(13%)가 1.97 log CFU/g수준으로, 관행농 11개(23%)에서 1.04 log CFU/g 수준으로 검출되었다. 그러므로 유기농산물과 관행농산물에서의 일반세균과 병원성 세균의 오염정도는 차이가 거의 없고 이들 병원성 미생물의 오염수준도 비교적 낮아 안전한 것으로 판단된다. To analyze the presence of microbes in organic farm produce, green chillies, lettuce, tomatoes, apples, pears, and rice were collected at 47 production sites with organic and conventional produce. Total average bacterial counts of 4.07 log CFU/g in organic green chillies, 3.71 log CFU/g in conventional green chillies, and 6.76- 6.90 log CFU/g in the both lettuce were detected. Mean bacterial counts of 4.48 log CFU/g and 2.84 log CFU/g were detected in organic and conventional pear produce, respectively. Differences in bacterial counts in tomatoes, apples, and rice in organic and conventional produce were less pronounced. Clostridium perfringens, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus were not detected in any produce sample. However, Bacillus cereus was detected with average counts of 1.04 log CFU/g in 11/47 (23%) conventional produce samples and 1.97 log CFU/g in 6/47 (13%) organic produce samples. Therefore, organic and conventional produce showed similar microbial prevalence patterns, and comparable safety in terms of pathogen contamination.