빌트인 모터를 이용한 2축 제어 미세 가공기 개발

김건희,김효식,양순철,이상용,국명호,이선규,김윤중,홍권희 한국공작기계학회 2007 한국공작기계학회 추계학술대회논문집 Vol.2007 No.-

This paper describes development of low cost precision machine that has combined the Build-in Motor with a vacuum chuck. This study mainly aims to find out a cutting condition for maintaining optimum surface condition and to examine cutting characteristics of the precision machine that is equipped by diamond bites. The cutting materials is Al alloy. Several experiments were carried out to find out the main factors that affect the surface roughness such as principal axis RPM(rotation per minute), feeding speed, and cutting depth. As a result, we obtain The optimum cutting condition of the developed precision machine.

전자토모그래피의 정량적 분석에서 대물렌즈 조리개의 영향

김진규,이상희,권희석,정종만,정원구,이수정,주형태,김윤중 韓國電子顯微鏡學會 2008 Applied microscopy Vol.38 No.4

Electron tomography의 정량적 분석을 위해서 대물렌즈 조리개가 투과빔의 강도에 미치는 영향을 평가하였다. Electron tomography에 도입되는 Beer’s law의 올바른 적용을 위해서는 투과빔은 시료의 기울기에 따른 mass thickness의 변화에 의한 효과만을 반영해야 한다. 그러므로 빔 경로상의 대물렌즈 조리개, 홀더 등에 의한 다른 효과는 제거되어야 한다. 본 연구에서는 대물렌즈 조리개의 cut-off 효과를 120 kV TEM과 Quantifoil holey 카본 시료를 이용하여 상세히 평가하였다. 대물렌즈 조리개를 사용하지 않은 경우와 비교할 때, 30 μm 크기의 대물렌즈 조리개를 통과한 투과전자빔의 강도는 약 16.7%의 감소가 일어난다. 또한 55˚이상의 고경사각 기울기에서는 대물렌즈 조리개의 cut-off 효과에 의해 14.2%의 강도 감소가 추가적으로 발생함을 알 수 있었다. Electron tomography에서 정량적 분석을 위해서는 이러한 대물렌즈 조리개의 영향을 고려해야만 한다. 또한 Beer’s law의 올바른 적용을 위해서는 일련의 기울기에 따른 2차원적 영상은 가능하면 대물렌즈 조리개를 사용하지 않은 상태에서 획득하는 것이 바람직하다. We have evaluated the effects of experimental factors on transmitted electron beam intensities for quantitative analysis in electron tomography. For the correct application of Beer’s law in electron tomography, the transmitted beam intensity should reflect the net effect of mass properties on beam path. So, the any other effects of the objective aperture and the specimen holder on beam path should be removed. The cut-off effects of objective aperture were examined using Quantifoil holey carbon film and a transmission electron microscope operated at 120 kV. The transmitted beam intensities with 30 μm objective aperture dropped about 16.7% compared to electron beam intensities without the objective aperture. Also, the additional losses of about 14.2% at high tilt angles were occurred by cut-off effects of the objective apertures. For the precise quantitative analysis in electron tomography, the effect of the objective aperture on transmitted electron beam intensities should be considered. It is desirable that 2-D tilt series images are obtained without the objective aperture for correct application of Bee’s law.

고전압 급준펄스의 오버슈트 개선에 관한 연구

곽희로,권동진,김영찬 崇實大學校 生産技術硏究所 1994 論文集 Vol.24 No.-

This paper describes very fast rising high voltage pules generation using the traveling wave theory of the transmission line. This very fast rising high voltage pulse generator consists of a charging coaxial cable, a discharging switch, and a terminating resistance. The results of the study show that the rising time of pulses is very fast about 30 [nsec]. The length of the coaxial cable and the charging voltage can regulate the duration and the amplitude or the polarity of the pulse. In addition, rod to plane electrodes are suitable as a short switch and the overshoot of pulse was improved with the larger radius of the rod electrode.

위암 환자에서 절제된 림프절 수의 차이와 관련이 있는 인자

정귀애,박정희,변익건,김경종,장정환,김권천,민영돈 朝鮮大學校 附設 醫學硏究所 2004 The Medical Journal of Chosun University Vol.29 No.1

Purpose: By the definition of UICC TNM classification (fifth edition), the nodal stage of gastric cancer is based on the number of metastatic lymph nodes, which is influenced by the number of resected lymph nodes. And individual differences in the number of resected lymph nodes had been observed in patients with gastric cancer. The aim of this study is to verify the factors which are associated with the difference in the number of resected lymph nodes in patients with gastric cancer. Methods: We reviewed 613 patients with gastric cancer who underwent curative resection and D2 lymph node dissection with 15 or more resected lymph nodes. The number of resected lymph nodes was analyzed according to the characteristics of patients, the types of operation and prognostic factors of gastric cancer. Results: The mean number of resected lymph nodes per patient was 33.0 (median: 31.0, range: 15-88). The number of resected lymph nodes was significantly associated with the types of operation, the location and size of tumor, macroscopic types, depth of tumor invasion and the number of metastatic lymph nodes. Patient's age, gender and the histopathological finding's had no relationship with the number of resected lymph nodes. Conclusions: The number of resected lymph nodes from gastric cancer was different in each patient despite of same D2 lymph node dissection and it was associated with several prognostic factors of gastric cancer.

조기위암의 형태학적인 분류에 따른 임파절 전이 양상

최은서,강길,박정희,장정환,김권천,김경종,민영돈 朝鮮大學校 附設 醫學硏究所 2004 The Medical Journal of Chosun University Vol.29 No.1

Currently, in the limited cases of early gastric cancer (EGC), endoscopic mucosal resection (EMR) is used for curative treatment. However, its completeness is still controversial. The purpose of this study was to review the suggested indications of EMR. We retrospectively analyzed 234 patients with EGC who underwent curative (RO) gastrectomy. The enrolled cases were further classified into mucosal and submucosal types, and mucosal EGC were further classified according to the size, gross type and histologic pattern. 133 patients had mucosal cancers and 101 patients submucosal. The overall incidence of positive lymph node was 14.1% (33/234), the incidence of mucosal cancer was 8. 3% (11/133), which was significantly lower than that of submucosal, 22% (22/101). Of 133 patients with mucosal EGC, 90 were smaller than 2㎝ in size and the incidence of lymph node metastasis was 5.6% (5/90), compared to 43 of larger than 2㎝ with the incidence of 14% (6/43). According to the gross type classification of mucosal cancer, incidence of lymph node metastasis in protruded type (EGC type Ⅰ, Ⅱa, Ⅰ+Ⅱa) was 15.4% (4/26), nat type(EGC type Ⅱb) 2. 9% (1/35), depressed type (EGC type Ⅱc, Ⅲ) 8.3% (6/72). Lymph node metastasis in differentiated type of mucosal cancer was 6.9% (5/72) and undifferentiatcd type 9.8% (6/61). In this study, there was no single indication free from lymph node metastasis, It is thought that the selection of EMR for the curative treatment of EGC should be considered carefully and more clinical studies with long-term follow up are necessary for EMR to be generally acceptable.

Nitrate and nitrite concentrations in the processed meat products sold in food markets

Hee-Sun Chae,Yeon-Jae Park,Ji-Eun Kim,Dong-Kyu Kim,Jong-Soo Kim,kyu-Hyun Kim,Doo-Hwan Kim,Young-Seob Kim,Hong-Rak Son,Kweon-Jung 한국예방수의학회 2017 예방수의학회지 Vol.41 No.1

Nitrite and nitrates are usually used in the production of meat products as food additives even though they pose a secondary risk. In this study, the residues of nitrite and nitrate ions in 366 processed meat products distributed in Seoul were analyzed using ion chromatographs and UV spectrophotometers. In all tested products, the residues of nitrite were below 70 mg/kg, which met the processing standard and component specification for livestock products. Evaluation of nitrite ions, revealed a mean concentration of 7.1 - 11.9 mg/kg in hams, sausages, and bacons, while higher ratios of nitrite were found in other types of products. Among the studied processed meat products, at least 60% of hams and sausages had indications of nitrite, as did 90% of bacons and dry meats. No spiced meat and less than 10% of crushed meat had indications of nitrite. However, all dried meats showed below 1 mg/kg, regardless of whether they had indications of nitrite. Up to 9.7 mg/kg of nitrite was detected in the products with no indication of nitrite, and 14.6% of all products had at least 1 mg/kg of nitrite. This can be attributed to the reduction of residual nitrate ions in the products into nitrite ions. A review of the concentrations of nitrate ions in processed meat products by type suggests that the mean concentration was 22.3 (maximum 110.2) mg/kg in hams, 31.8 (maximum 89.5) mg/kg in sausages, 16.4 (maximum 28.2) mg/kg in bacons, 16.8 (maximum 61.1) mg/kg in spiced meats, 20.2 (maximum 99.4) mg/kg in crushed meats, and 121.0 (maximum 216.5) mg/kg in dried meats. Therefore, dried meats showed much higher nitrate ion concentrations than other types of meat products; however, the residue of nitrite ions in actual dried meats was found to be lower than 1 mg/kg, suggesting that the concentrations of nitrate ions do not affect those of nitrite ions. However, a certain concentration of nitrate ions was observed even when nitrate ions were not used in the products, as nitrite ions were transformed into nitrate ions and nitrite ions were detected even the products with no indication of nitrite ions. Therefore, continuous monitoring and preparation of relevant standards of the use of nitrate in processed meat products are necessary.

Menu Composition Evaluation of Meal Boxes Sold from Convenience Stores and Franchise in Seoul

Ouk Hee Kim,Nam Hun Kim,Young Ae Park,Li La Kim,Jun Kung Kim,In Sook Hwang,Young Hee Oh,Kweon Jung 한국식품영양과학회 2016 한국식품영양과학회 학술대회발표집 Vol.2016 No.10

A Prospective Nationwide Study of Drug-Induced Liver Injury in Korea :

Suk, Ki Tae,Kim, Dong Joon,Kim, Chang Hoon,Park, Seung Ha,Yoon, Jai Hoon,Kim, Yeon Soo,Baik, Gwang Ho,Kim, Jin Bong,Kweon, Young Oh,Kim, Byung Ik,Kim, Seok Hyun,Kim, In Hee,Kim, Ju Hyun,Nam, Soon Woo American College of Gastroenterology 2012 The American journal of gastroenterology Vol.107 No.9

Derivation of Cell Adapted Sacbrood Virus from Korean Native Honeybee

Mi-Sun Yoo,Chang-Hee Kweon,Young-Ha Kim,Nam-Hee Kim,Ha-Na Jung,Kondreddy Eswar Reddy,Suk-Chan Jung,Seung-Won Kang 한국응용곤충학회 2013 한국응용곤충학회 학술대회논문집 Vol.2013 No.10

Sacbrood virus (SBV), a causative agent of larval death in honeybees, is one of the most devastating diseases in bee industry throughout the world. Lately the Korean Sacbrood virus (KSBV) induced great losses in Korean honeybee (Apis cerana) colonies. However, there is no culture system available for honeybee viruses, including SBV, therefore, the research on honeybee viruses is practically limited until present. In this study, we investigated the growth and replication of KSBV in cell cultures. The growth of KSBV was demonstrated by RT-PCR, quantitative real-time PCR, TEM and nucleotide sequence analysis. The results demonstrated that SBVshowed the replication signals in mammalian cell lines, including Vero cells without any signs of cytopathic effect (CPE). The results of RT-PCR, quantitative real-time PCR and in vivo infection with KSBV were also indicated the replication. Phylogenetic tree analysis shows our sequence included in distinct group with other SBV strains from China and Korea. It clearly showed the differenciation between field strain and attenuated strain through cell culture. The results of present study demonstrated for the first time that SBV like other animal viruses could be adapted and attenuated in cells through the sequential passages. The sequential adaptation through cell culture could result in discrepancy of pathogenicity of virus and morphological characterization. For this reason, the present results indicated that the cell adapted SBV could be a valuable tool to study the general properties of this emerging virus, including pathogenicity in the future.

Change of Physiochemical Properties after Cold Water Irrigation in Japonica rice

Kim Ki-Young,Choi Yoon-Hee,Shin Mun-Sik,Kim Bo-Kyeong,Choung Jin-Il,Ko Jae-Kweon,Kim Jung-Gon 한국작물학회 2005 한국작물학회 학술발표대회 논문집 Vol.2005 No.-