기기 중성자방사화분석법을 이용한 황사특성

임종명,이현석,이진홍 忠南大學校 環境問題硏究所 2002 環境硏究 Vol.20 No.-

Using INAA, which has been thought to be one of the best analytical techniques for airborne particulate matters, this study centered on the quantitative analysis of 32 metal elements within Asian Dust aerosols. Concentrations of REEs of crustal origin, such as Ce, Cs, Dy, La, Sc, and Sm were more than 8.5 times higher in Asian Dust aerosols. In addition, major crustal elements, such as Al, Ca, Co, Fe, K, Mg, Mn, and Ti showed more than 3 times higher concentrations in those aerosols, which made PM 10 and all metal concentrations be also about 3.0 and 4.8 times higher, respectively. However, concentrations of anthropogenic origin, such as As, Br, Ci, I, In, Sb, Se, and Zn were increased to be a little higher, which means no great effect of Asian Dust on these elements.

리모델링을 위한 공동주택 조립기준면의 영역성 및 위계성 설계방안에 관한 연구

임석호,송성진 대한건축학회 2003 대한건축학회논문집 Vol.19 No.7

Twenty years following their erection, the reconstruction of RC-structured apartment houses in Korea is under discussion. The life span of those houses in Korea is significantly shorter than those in other countries. For example, the average life span of similar buildings in Britain is 141 years, in France 86 years, in Germany 79 and in Japan 30 years. Repair or extensions are made for the followings reasons when there is room for a floor area ratio: economic and social reasons, life style matters, the appropriateness of the area, and limitations of functional durability. As mentioned above, the functional life is as important as the physical life. In particular, unlike other components, the life span of structure is exceptionally long and they do not age rapidly. For this reason, it is important to develop a method to maintain the components of rooms in the house in a systematical manner, serving the ultimate goal - elongating the functional life. As part of environmental-preserving policies, this study attempts to present the basic information crucial for the implementation of long-life houses by seeking MC and LC design application methods to extend the functional life of the components of the room in the apartment houses which is easy for remodeling and also to adopt zonning and hierarchy.

ICP-AES를 이용한 대기분진 중 중금속 분석에 대한 정도관리

임종명,이현석,이진홍 忠南大學校 環境問題硏究所 2003 環境硏究 Vol.21 No.-

In this study, factors of quality control such as laboratory environment, capability of instrument/equipment, method of analysis, calibration, and standard solution were investigated to obtain quality assurance when analyzing airborne heavy metals (e.g., Pb, Cr, Cd, Cu, Mn, Ni, Fe) using ICP-AES. A procedure of quality assurance and evaluation method of uncertainty are also suggested by applying ISO Guide. The suggested process of quality assurance will be helpful for the national monitoring network to produce better data.

대전 3, 4 공단지역의 대기 중 PM 2.5내 미량금속의 특성

임종명,이현석,이진홍 忠南大學校 環境問題硏究所 2003 環境硏究 Vol.21 No.-

This study centered on the quantitative analysis of about 27 trace metals including toxic ones of airborne PM 2.5 in the 3rd and 4th industrial complex area of Daejeon city, Korea. For analytical quality control, the certified reference material (NIST, the National Institute of Standards and Technology, U.S.A., SRM 2783, Air particulate on filter media) was used. The errors relative to SRM values of Sb, Mn, V, Ca, Mg, Na, K, Ti, Co, Zn, and Sm fell below 5%, while those of Cr, Fe, Ba, Th, Ce, Al, and Cu were less than 10%. From the results of the quantitative analysis using INAA, the concentxation of toxic metals such as As, Mn, Se, V, and Zn were 2.40±1.99ng/m^(3), 6.54k3.15 ng/m^(3), 1.17±0.66 ng/m^(3), 1.1150.58 ng/m^(3), 52.31±25.92 ng/m^(3), respectively. If compared in terms of enrichment factors, it was found that certain elements (e.g., In, Cu, Zn, As, C1, I, Br, Sb, and Se) are enriched in PM 2.5 samples of the study site. The results of factor analysis by SPSS shows that 70.0% of total variance is well explained.

FEM을 이용한 선삭가공 절삭조건의 영향 분석

임세환,송춘삼,홍석관,강정진,김주현 한국공작기계학회 2007 한국공작기계학회 추계학술대회논문집 Vol.2007 No.-

A plane strain finite element model is developed to simulate turning with continuous chip formation using adaptive remeshing during the thermal-mechanical coupled analysis. Comparisons between the experimental and simulation results for cutting forces are performed to validate FE analysis results. Influences of machining parameters such as depth of cut, cutting speed and feed rate on cuting force and shear angle are analyzed by Taguchi method. The more depth of cut and feed rate result in the increase of cutting forces, but the rates of increase are decrease due to the larger shear angle. As the cutting speed increases, von Mises stress of workpiece near the tool tip decreases because the strength of specimen decreases at high temperature above 500℃. This thermal effect on cutting force is negligible because the affected area is very localized and the average values of von Mises stress in the shear plane are the same among the diverse cutting parameters.

Genetic algorithm을 이용한 supply chain network에서의 최적생산 분배에 관한 연구

임석진,정석재,김경섭,박면웅 한국경영과학회 2003 한국경영과학회 학술대회논문집 Vol.- No.1(1)

Recently, a multi facility, multi product and multi period industrial problem has been widely investigated in Supply Chain Management (SCM). One of the key issues in the current SCM research area involves reducing both production and distribution costs. The purpose of this study is to determine the optimum quantity of production and transportation with minimum cost in the supply chain network. We have presented a mathematical model that deals with real world factors and constraints. Considering the complexity of solving such model, we have applied the genetic algorithm approach for solving this model computational experiments using a commercial genetic algorithm based optimizer. The results show that the real size problems we encountered can be solved in reasonable time.

수용성 키틴이 백서 창상치유에 미치는 영향

강장석,조용남,정상훈,유 결,임진수,권 호,조용우,고석원 大韓成形外科學會 2001 Archives of Plastic Surgery Vol.28 No.1

흉골골절이 의심되는 외상환자에서 초음파의 진단적 효용성

염석란,김재광,이근,박철완,양혁준,현성열,임용수,진욱 대한응급의학회 2001 대한응급의학회지 Vol.12 No.3

Purpose: This study compared the value of ultrasonography(US) in the diagnosis of sternal fractures with those of conventional radiography and bone scan. Material and Method: From March 2000 to March 2001, in Gil Medical Center, Gachon Medical College, 44 patients(22 women and 22 men, mean age 46 years, range 5∼81 years) complained of tenderness in the sternal area. The cases histories of these patients with clinically suspected sternal fracture due to blunt trauma were prospectively studied. At the time of admission, conventional radiography(sternal view) was done. At one day after admission, sternal ultrasonography was obtained, and after 4∼5 days, a bone scan was done. Sternal ultrasonographic findings, conventional radiographic findings, and bone-scan findings were compared. In addition, a 12-lead ECG was done. When it was necessary, cardiac enzyme was checked and echocardiography was performed. Result: In 21 of 44 patients(48%), a sternal fracture was found by sternal US. Only 9 of 21 patients (43%) were diagnosed as having a sternal fracture by using conventional radiography. 23 of 44 patients (52%) have negative findings on sternal US; they also had negative findings on conventional radiography. Except for 7 unchecked patients, 13 of 21 patients(62%) were diagnosed as having a sternal fracture by bone scan, and among the 23 patients who had negative findings on sternal US, the 19 patients checked with a bone scan also had negative findings. Conclusion: Sternal US can find sternal fractures that are difficult to find on conventional radiography. Compared with bone scan, sternal US takes a shorter time and sternal US is not difficult. Additionally, combined lesions with sternal fractures(peristernal hematoma, soft tissue swelling) and costar cartilage fractures are diagnosed more easily when using sternal US.

뇌자기공명영상촬영술상 병변을 관찰할 수 없는 허혈성 뇌경색

김진석,김태완,임정근 啓明大學校 醫科大學 1998 계명의대학술지 Vol.17 No.4

1. 임상적으로 뇌졸중이 의심되어 증상 발생후 24시간에서 2개월까지 Brain MRI을 실시한 722명의 환자들 중 결과가 가음성인 환자는 모두 22명 (3.1%)이었다. 2. Brain MRI상 병변은 관찰되지 않으나 임상 양상 및 신경학적 이상 소견으로 추정되는 병변의 위치를 구분해 보면 뇌간부가 13명 (59%)으로 가장 많았고, 피질하부 8명 (36%), 피질 1명 (4.5%)의 순 이었다. 3. 대뇌혈관 (large cerebral artery)폐쇄 보다는 분지 동맥 (branch artery)이나 소 관통동맥 (small perforating artery)의 폐쇄에 의한 것으로 추정되는 허혈성 뇌경색의 병변의 빈도가 높았다. 4. 병력, 뇌졸증 위험 인자, 임상 양상, 심전도 검사, 심초음파 검사 및 뇌혈관조영술등에서 혈전성 뇌경색은 12명 (55%), 색전성 뇌경색은 3명 (13%), 원인이 확실하지 않은 경우는 7명(32%)으로 혈전성 뇌경색의 빈도가 뚜렷하게 높았다. 5. T1강조 영상, T2,강조 영상 및 FLAIR sequence를 같이 실시함으로써 허혈성 뇌경색의 조기 발견은 과거의 연구 보고에 비하여 상당히 높아졌으나 계속적으로 Brain MRI상 가음성인 허혈성 뇌경색이 있음으로, 허혈성 뇌경색의 조기 진단에는 새로운 기법인 확산강조 자기공명영상, 관류강조 자기공명영상, 자기공명 분광경 등의 다른 특수한 Brain MRI이 필요할 것으로 생각되며, 항상 신경학적인 검사를 통한 임상적인 진단이 선행되어야 한다. Background : Brain magnetic resonance imaging (MRI) is more sensitive than computed tomography in the diagnosis of acute ischemic stroke, but may not visualize all acute ischemic stroke. For deeper understanding of MRI negative strokes, we reviewed case histories, abnormal neurological finding, and localized ischemic lesions presumedly which were not present in brain MRI scans. Methods : Patients with a clinically definite first ischemic stroke and absence of corresponding lesion in brain MRI scans were studied retrospectively with hospital records dating from January 1994 to November 1996 and prospectively from December 1996 to August 1997. Patient with transient ischemic stroke, postictal paralysis, central nervous system infection, demyelinating disease, hemiplegic migraine, functional or hysterical cause, multiple cerebral infarction, scans within 24 hours and equivocal findings were excluded. Brain MRI was scanned with T2WI, T1WI and FLAIR sequence. Results: We studied 722 patients with clinically diagnosed definite acute ischemic stroke during the study period and identified 22 patients (3.1%) with the absence of corresponding lesion in brain MRI scan. The ischemic strokes without brain lesions on MRI scan were clinically localized to the brain stem (n=13, 59%), subcortex (n=8, 36%) and in the cortex (n=1, 4.5%). Perforating arterial and thrombotic ischemic lesions seemed to be more common than large arterial & embolic lesions. Risk factors was not different between MRI positive and MRI negative ischemic stroke. Summary: Acute ischemic stroke with absence of brain lesion in MRI scans is more common in brain stem and subcortex than in the cortex. There is some potential limitation of standard MRI scan for diagnosis of acute ischemic stroke, therefore further scans with new imaging studies such as perfusion/diffusion weighted magnetic resonance imaging are required in selected cases.

비내시경을 이용한 안와 내벽 골절 정복 2예

김진국,남태욱,임채형,김재영,김정석 건국대학교 의과학연구소 2001 건국의과학학술지 Vol.11 No.-

Traditional surgical approaches to orbital medial wall fractures are either extraocular skin incision or indirect bicoronal flap. However these methods can leave remarkable orbital scar or scalp alopecia with possible complications. Endoscopic intranasal visualization of the medial orbital wall and lamina papyracea is a technique familar to otolaryngologists. This endoscopic view allows confirmation of fracture of medial orbital wall and herniation of orbital contents. Good visualization of the fracture can facilitate the anatomic reduction of orbital contents and the proper placement of orbital implant. Two cases of medial orbital wall fracture repaired by intranasal endoscopy using silastic sheet are reported.