• 제목/요약/키워드: General X-ray

검색결과 555건 처리시간 0.034초

경계요소법에 의한 이종재료 접합 잔류열응력의 해석 (A Study on the Bonding Residual Thermal Stress Analysis of Dissimilar Materials Using Boundary Element Method)

  • 이원;유영철;정의섭;윤인식
    • 비파괴검사학회지
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    • 제15권4호
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    • pp.540-548
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    • 1996
  • 전자 부품의 일종인 LSI 패키지의 제조 과정에서 절연 방진 방습 등을 목적으로 수지 몰딩이 널리 사용되고 있는데, 냉각과정에서 금속과 수지의 계면에 접합 잔류열응력이 발생하여 파괴의 원인이 되고 있다. 접합 잔류열응력의 측정에는 X선 회절법등이 사용되지만 측정상의 어려움과 계면단 응력특이성에 대한 해석의 곤란함 때문에 적절한 모델링에 따른 수치해석적 연구가 새로이 주목을 받고 있다. 본 연구에서는 Al/Epoxy를 몰딩 접합한 세가지의 대표적인 계면 형상을 선정하여 계면에서의 잔류열응력을 경계요소 수치해석 및 스트레인 게이지를 이용한 실험을 통하여 각각 해석하였다. 수치해석과 실험결과는 정성적으로 잘 일치하였으며, 서브 요소를 사용하므로써 계면단 응력 특이성의 해석 정밀도를 향상시킬 수 있었다. 또한 접합 잔류열응력의 해석결과로부터 수직응력에 의한 계면 박리가 예상되고, 피착체의 두께가 증가할수록 응력 특이성이 강하게 나타남을 확인하였다.

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Rhese법 촬영에서 시신경구멍의 이중 각도에 대한 연구 (A Study on Double Angle of Optic Foramen in the Rhese Method)

  • 박상조;유지나;유명석;허영철
    • 한국방사선학회논문지
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    • 제11권5호
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    • pp.313-319
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    • 2017
  • 본 연구의 목적은 한국인의 시신경구멍의 이중각도를 확인하여 Rhese법에 적용하는 것이다. 먼저 3차원 CT의 MPR 기법을 이용하여 축상면 영상에서 좌측 안구와 정중시상면 사이의 각도를 측정하였다. 두 번째는 MPR 영상의 시상면에서 좌측 안구의 시신경구멍과 OML 사이의 각도를 측정하였다. 시신경과 정중시 상면 사이의 각도는 평균 $39.9{\pm}4.63^{\circ}$ 였고, 이는 Rhese 방법으로 제시해 오던 $53^{\circ}$ 와 달랐음을 확인하였다(p<0.05). 시신경구멍과 OML 사이의 각도는 $40.8{\pm}6.6^{\circ}$ 였다. 결론적으로 본 연구는 현행 교과서에서 제안 된 Rhese 방법의 표준이 한국인에게 적용하기 어려움을 의미한다. 따라서 다양한 일반촬영법에서 한국 표준의 각도의 연구가 필요하고 이에 본 연구가 기초 자료로 활용될 것이라 사료된다.

Molecular Orientation of Intercalants Stabilized in the Interlayer Space of Layered Ceramics: 1-D Electron Density Simulation

  • Yang, Jae-Hun;Pei, Yi-Rong;Piao, Huiyan;Vinu, Ajayan;Choy, Jin-Ho
    • 한국세라믹학회지
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    • 제53권4호
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    • pp.417-428
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    • 2016
  • In this review, an attempt is made to calculate one-dimensional (1-D) electron density profiles from experimentally determined (00l) XRD intensities and possible structural models as well in an effort to understand the collective intracrystalline structures of intercalant molecules of two-dimensional (2-D) nanohybrids with heterostructures. 2-D ceramics, including layered metal oxides and clays, have received much attention due to their potential applicability as catalysts, electrodes, stabilizing agents, and drug delivery systems. 2-D nanohybrids based on such layered ceramics with various heterostructures have been realized through intercalation reactions. In general, the physico-chemical properties of such 2-D nanohybrids are strongly correlated with their heterostructures, but it is not easy to solve the crystal structures due to their low crystallinity and high anisotropic nature. However, the powder X-ray diffraction (XRD) analysis method is thought to be the most powerful means of understanding the interlayer structures of intercalant molecules. If a proper number of well-developed (00l) XRD peaks are available for such 2-D nanohybrids, the 1-D electron density along the crystallographic c-axis can be calculated via a Fourier transform analysis to obtain structural information about the orientations and arrangements of guest species in the interlayer space.

염료공장 근로자의 직업성 천식에 관한 역학적 연구 (Health characteristics and symptom of workers in reactive dye industries)

  • 이경종;문영한;노재훈;박해심;홍천수
    • Journal of Preventive Medicine and Public Health
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    • 제23권3호
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    • pp.338-344
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    • 1990
  • This study investigated the symptoms, medical and occupational history of 424 workers of 5 reactive dye Industries in the Inchon area in Korea. The study was performed on March 6 and July 19, 1989. The tests applied to the subjects were : serum total IgE, specific IgE, skin prick test with 7 inhalatory antigens, pulmonary function test, chest X-ray, methacholine test, and bronchoprovocation test. The workers were classified according to these tests into 4 groups (healthy, realtively healthy, need careful medical observation, and occupational asthma), and were compared in terms of the group characteristics and the symptom prevalence. The prevalece of occupational asthma of workers in reactive dye was 5.9% Significant differences were observed among the 4 groups. The groups were significantly different in the variables of sex and duration of smoking among their general characteristics ; and dyspnea, wheezing, chest pain, cough, nasal symptoms and sore throat among symptoms ; asthma, bronchitis, and other respiratory diseases with respect to their past medical history. This study suggests that we should pay special attention to the workers exposed to the risk of occupational asthma.

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Eagle씨 증후군의 치험례 (CASES REPORT OF EAGLE'S SYNDROM)

  • 이상철;김여갑;류동목;오승환;윤옥병;지유진
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제18권3호
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    • pp.435-442
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    • 1996
  • Eagle's syndrome is the term given to symtomatic elogation of the styloid process or mineralization of the stylohyoid or stylomandibular ligament. Since ossification of stylohyoid ligament at cadeva was fist described by De Manchetis in 1652 and Weinlecher described clinical symptom which produced by elongated styloid process and osteotomy of styloid process in 1872, Clinical symtom which include sensation of a foreign body on the pharynx, dysphagai, dysphonia, referred pain, and mouth opening disturbance was termed by Eagle as Eagle's syndrome. then, case reports of Eagle's syndrome are presented. in these cases, the patient's chief complaints included periauricular radiating pain, mouth opening disturbance, foreign body sensation, dysphagia, tenderness on the neck. Through vairous X-ray examination and palpation of tonsillar fossa, elongated styloid process were confirmed. Under the general anesthesia there were successfully removed out via transoral approach technique, described by Eagle. after resented styloid process, they were freed from the symptoms without further complication. Therefor we reported these cases treated by surgical resection of styloid process with good results.

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단순 피부병변으로 간과되어 급성 호흡곤란 증후군으로 진행된 쯔쯔가무시병 1예 (A case of ARDS Overlooked Tsutstugamushi Disease that Presented as Simple Cutaneous Lesions)

  • 유기현;김기홍;김종대;손지웅;나문준;최유진
    • Tuberculosis and Respiratory Diseases
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    • 제61권4호
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    • pp.389-393
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    • 2006
  • 저자들은 홍반성 구진양 발진으로 발현된 쯔쯔가무시병환자에서 단순 피부질환으로 간과하여 치료의 시기가 지연되고 스테로이드 등의 약물 사용으로 급성 신부전 및 급성 호흡부전으로 진행된 1례를 경험 하였기에 문헌 고찰과 함께 보고하는 바이다.

성인 비만의 건강특성에 관한 분석적 연구 (An Analytical Study on Health Characteristics of Obesity of Adulthood)

  • 탁기천;류규수
    • 보건교육건강증진학회지
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    • 제18권2호
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    • pp.115-128
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    • 2001
  • This study was carried out to offer the basic data for more qualitative lives of the adulthood with obesity through their health maintenance and control. So, the researcher reviewed and analyzed the health problems of the subjects according to sex, age, and positive rate on the screening tests. The subjects were 91 obese persons in K university hospital in Seoul from December 1, 2000 to January 31, 2001. A Questionnaire developed by researcher to obtain subject's general characteristics, main symptoms, medical examination, diagnosed disease was used as the tool for the study. The results of this study are as follows: 1. For the distribution of diagnosis in subjects, liver disease was most frequent and hypertension was second. 2 The most common complaints were indigestion in the digestive system, throat pain in the respiratory system, dyspnea in cardiovascular system, thirsty in endocrine system, frequent urine in the urinary system, vertigo in the hematologic system. 3. The main symptoms according to sex were for females, a statistically significant higher rate of complaints in the digestive system, musculoskeletal system as compared to males. 4. The main symptoms according to age were that in the fourth decade there were higher rate of complaints in the musculoskeletal system. 5. In screening tests according to sex, males showed a higher positive rate for Alk-Phosphatase and females, in FBS, urine-micro, VDRL. 6. In screening tests according to age, higher positive rates of BP, Chest X-ray, mammography, ESR, CRP were seen in the fourth decades. 7. Obesity was positively related to cardiovascular system, endocrine system, urinary system, musculoskeletal system, mental and nervous system in main symptoms. 8. Obesity was positively related to BP, Sonography, FBS, SGOT, SGPT in screening tests.

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유리 생비골 및 생비골 피부편 이식 후 공여부의 평가 (The Evaluation of Donor Site after Transfer of Free Osseous and Osteocutaneous Flap of Fibula)

  • 이광석;한승범;황인철;송형석
    • Archives of Reconstructive Microsurgery
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    • 제10권2호
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    • pp.75-80
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    • 2001
  • Purpose : We have evaluated the morbidity of donor site after transfer of free fibular osseous and osteocutaneous flap to defect site of bone and soft tissue due to chronic osteomyelitis of long tubular bone, open fracture with bony defect, bone or soft tissue tumor and congenital anomaly. Materials and methods : The 54 cases of 79 cases to be carried out from May, 1982 to May, 2001 which could be followed up were reviewed. There were forty nine in male and five in female. The mean age was 35(4 to 66)years old and mean follow up period is 21.3 month(12 to 72). We have retrospectively analyzed the various postoperative complications such as compartment syndrome, donor site infection, skin defect, hypesthesia, hammer toes, ankle instability and activity of daily living by help of questionnaire, telephone, physical examination, follow up x-ray study and chart. Results : In the total 54 cases the medication period for pain control after operation were classified into three groups under 2 weeks(49 cases), from 2 weeks to 6 weeks(3 cases) and over 6 weeks(2 cases). The postoperative morbidity were occurred in total 12 cases(compartment syndrome: 0, infection : 2, skin defect: 1, hypesthesia: 5, hammer toe: 2 ankle pain: 2 discomfort in activity of daily living: 0), and also the morbidity rates of donor site were 23.5% in osseous flap and 21.6% in osteocutaneous flap were occurred. There was no statistical significonce in morbidity between osseous and osteocutaneous free fibular flap transfer(P>0.05). Discussion : In general the morbidity of free fibular flap transfer was relatively high but it did not have any effect on daily activity of living. We think that the meticulous operation technique, detailed wound care and early range of motion exercise will reduce the morbidity of donor site of flap.

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장중첩증의 임상양상을 보였던 영아의 중장 염전증(Midgut volvulus) 1례 -복부 초음파검사를 이용한 진단- (Midgut Volvulus of Infant Simulating Intussusception Diagnosis with Color Doppler Ultrasonography)

  • 이해경;김제우;오필수;이영아;최하주;윤혜선;양익;이경원;이재정
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제1권1호
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    • pp.133-137
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    • 1998
  • Although midgut volvulus is clinically characterized by bilous vomiting and abdominal distention, plain abdominal X-ray is usually non-specific and therefore it can be misdiagnosed to other diseases. Upper gastrointestinal contrast study and computed tomography have been used as a routine diagnostic tool but it takes cost and time. Abdominal ultrasonography is a relatively good alternatives in diagnosing midgut volvulus and it relatively saves cost and time. But case presentation of midgut volvulus diagnosed with abdominal ultrasonography are rarely found in literature. We experienced a 6 month old girl who had come to our hospital with bilous vomiting and was diagnosed as midgut volvulus with ultrasonography. Thus we report this case with the presentation of typical ultrasonographic findings of midgut volvulus.

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