• Asian-Australasian Journal of Animal Sciences
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• 제18권5호
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• pp.728-733
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• 2005

The frequency and distribution of lymphoma caused by bovine leukemia virus (BLV) infection in various organs were investigated. Lymphoma samples were obtained from slaughtered cattle or from cattle submitted to the National Veterinary Research and Quarantine Service, Korea. Thirty female Holstein-Friesian dairy cattle aged over three years with the BLV-associated lymphoma were studied. None of the Korean native cattle (Hanwoo) had lymphoma in this study however. Lymphoma tissues were gray to pink in color, soft in consistency, and bulged from the cut surface. In advanced lymphoma tissues, there was great variety in the appearance of involved structures due to hemorrhage, necrosis, and/or calcification. Neoplastic tissues were observed in lymph nodes in all lymphoma cases. Intestine (96.4%), heart (88.9%), stomach (73.1%), and diaphragm (62.5%) were frequently involved with lymphoma. However, there was no lymphoma detected in liver. Large neoplastic masses, sometimes reaching the size of over 20 cm, were found in the abdominal cavities. It is suggested that metastasis of lymphomas occurs mainly via lymph based on gross observations; neoplasia may have been initiated in the serosal surface of the lung, heart, peritoneum, and numerous hollow organs in the abdominal cavity. Also many organs in the abdominal and thoracic cavity were affected by neoplastic tissues simultaneously. Characteristics observed in this study could be used as criteria to differentiate BLV-associated lymphoma from other nodular lesions in the slaughterhouse and as fundamental data to make clear the mechanism of metastasis or pathogenesis of EBL.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.2410-2412
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• 2005

In this study, two types of PS substrate were fabricated for sensing of chemical and biological substances. For sensing of the humidity and chemical analyzes such as $CH_3OH$ or $C_2H_5OH$, PS layers are prepared by photoelectrochemical etching of silicon wafer in aqueous hydrofluoric acid solution. To evaluate their sensitivity, we measured the resistance variation of the PS diaphragm. As the amplitude of applied voltage increases from 2 to 6Vpp at constant frequency of 5kHz, the resistance variation for humidity sensor rises from 376.3 to $784.8{\Omega}$/%RH. And the sensitivities for $CH_3OH$ and $C_2H_5OH$ were 0.068 uA/% and 0.212 uA/%, respectively. For biological sensing application, amperometric urea sensors were fabricated based on porous silicon(PS), and planar silicon(PLS) electrode substrates by the electrochemical methods. Pt thin film was sputtered on these substrates which were previously formed by electrochemical anodization. Poly (3-methylthiophene) (P3MT) were used for electron transfer matrix between urease(Urs) and the electrode phase, and Urs also was by electrochemically immobilized. Effective working area of these electrodes was determined for the first time by using $Fe(CN)_6^{3-}/Fe(CN)_6^{4-}$ redox couple in which nearly reversible cyclic voltammograms were obtained. The $i_p$ vs $v^{1/2}$ plots show that effective working electrode area of the PS-based Pt thin film electrode was 1.6 times larger than the PLS-based one and we can readily expect the enlarged surface area of PS electrode would result in increased sensitivity by ca. 1.6 times. Actually, amperometric sensitivity of the Urs/P3MT/Pt/PS electrode was ca 0.91uA/$mM{\cdot}cm^2$, and that of the Urs/P3MT/Pt/PLS electrode was ca. 0.91uA/$mM{\cdot}cm^2$ in a linear range of 1mmol/L to 100mmol/L urea concentrations

• 한국전기전자재료학회논문지
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• 제32권3호
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• pp.207-212
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• 2019

A flat-type piezoelectric ceramic ultrasonic transmitter was successfully fabricated for application in acoustic devices with cone-free diaphragms. The transmitter, possessing a center frequency of 40.6 kHz, exhibited a higher displacement characteristic for a multilayer type compared with a single layer type. Surface roughness treatment of an Al elastic diaphragm influenced a slight increase (1.1 dB) in the sound pressure level (SPL) at $10V_{rms}$ due to the enlarged surface area. The fabricated multilayer piezoelectric ceramic ultrasonic transmitter showed increasing SPL with increasing input voltage, with a maximum SPL of approximately 123.6 dB at $10V_{rms}$. This implies a doubly increased SPL density of $3.6dB/mm^3$, superior to that of a commercial open-type transmitter with a cone.

• Journal of Trauma and Injury
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• 제22권1호
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• pp.77-86
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• 2009

Purpose: The appropriate management of traumatic truncal arterial injury is often difficult to determine, particularly if the injury is associated with severe additional truncal lesions. The timing of repair is controversial when patients arrive alive at the hospital. Also, there is an argument about surgery versus stent-graft repair. This study's objective was to evaluate the appropriate method and the timing for treatment in cases of truncal abdominal injury associated with other abdominal lesions. Methods: The medical records at Ajou University Medical Center were reviewed for an 8-year period from January 1, 2001, to December 31, 2008. Twelve consecutive patients, who were diagnosed as having had a traumatic truncal arterial injury, were enrolled in our study. Patients who were dead before arriving at the hospital or were not associated with abdominal organ injury, were excluded. All patients involved were managed by using the ATLS (Advanced Trauma Life Support) guideline. Data on injury site, the timing and treatment method of repair, the overall complications, and the survival rate were collected and analyzed. Results: Every case showed a severe injury of more than 15 point on the ISS (injury severity score) scale. The male-to-female ratio was 9:3, and patients were 41 years old on the average. Sites of associated organ injury were the lung, spleen, bowel, liver, pelvic bone, kidney, heart, vertebra, pancreas, and diaphragm ordered from high frequency to lower frequency. There were 11 cases of surgery, and one case of conservative treatment. Two of the patients died after surgery for truncal organ injury: one from excessive bleeding after surgery and the other from multiple organ failure. Arterial injuries were diagnosed by using computed tomography in every case and 9 patients were treated by using an angiographic stent-graft repair. There were 3 patients whose vessels were normal on admission. Several weeks later, they were diagnosed as having a truncal arterial injury. Conclusion: In stable rupture of the truncal artery, initial conservative management is safe and allows management of the major associated lesions. Stent grafting of the truncal artery is a valuable therapeutic alternative to surgical repair, especially in patients considered to be a high risk for a conventional thoracotomy.

• 전자공학회논문지D
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• 제35D권11호
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• pp.46-54
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• 1998

직선 또는 필라멘트 모양의 NiCr 박막 히터 및 Bi-Sb 박막 열전퇴(thermopile)로 구성되는 평면형 Bi-Sb 다중접합 열전변환기를 제작하고, 10 Hz에서부터 10 ㎑까지의 교류 입력신호에 대한 변환기의 교류-직류 변환 특성을 논의하였다. 변환기의 열감도를 증가시키고 또한 교류-직류 변환오차를 감소시키기 위하여, NiCr 히터 및 Bi-Sb 열전퇴의 고온 접합부를 열차단막 역할을 하는 Si₃N₄/SiO₂/Si₃N₄ 다이아프램위에 각각 형성하였고, 열전퇴의 저온 접합부는 방열판 역할을 하는 실리콘 림(rim)에 의해 지지되는 Si₃N₄/SiO₂/Si₃N₄ 박막위에 형성하였다. 단일 bifilar NiCr 히터가 내장된 변환기의 열감도는 공기 및 진공중에서 각각 약 14.0 ㎷/㎽ 및 54.0 ㎷/㎽였고, 교류-직류 전압 및 전류 변환 오차범위는 공기중에서 각각 약 ±0.60 ppm 및 ±0.11 ppm이었다. 변환기의 교류-직류 변환 정확도가 상용 3차원 구조의 다중접합 열전변환기의 것보다 훨씬 더 높게 개선되었으나, 시간에 따른 출력 열기전력의 변화는 비교적 높게 나타났다.

• Journal of Chest Surgery
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• 제8권2호
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• pp.149-152
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• 1975

In spite of great advances in surgical treatment during past several decades, surgery of the trachea failed to develop correspondingly, partly because of relative rarity of the tracheal lesions and partly because of difficulties in surgical technique and anesthesia. Surgical diseases of the trachea are largely obstructions due to neoplasm or cicatrical stenosis and tracheal malacia. The present treatment of respiratory failure, using cuffed endotracheal and tracheostomy tubes, has produced, apparently with increasing frequency, tracheal stenosis, tracheomalized tracheal erosion. Surgery is presently the only reasonable way to treat stenotic lesions of the tracheobronchial tree. In the case of tumors, the current trend has been that of radical excision. Primary end-to--end reconstruction of the trachea has been generally recognized as the ideal method of repair following resection. However, for decades it was believed that a maximum of four tracheal rings only might be excised and primary healing achieved with safety. A great variety of procedures, developed by numerous investigations and directed at tracheal substitution, have almost invariably met with discouraging results. A meticulous study done by Grillo and associates on autopsy specimens has shown that an average 6.4cm of mediastinal trachea can be safely resected by full mobilization of the right lung and transplantation of the left main bronchus into the bronchus intermedius. Recently, we experienced a case of successful resection of a tumor of the tracheal carina and primary tracheo-left main bronchial anastomosis at the Department of Thoracic & Cardiovascular Surgery, the National Medical Center in Seoul. The patient, a 29-year-old man, was admitted to the hospital with complaints of dyspnea and cough. On admission, chest film showed hydropneumothorax on the right. After closed thoracostomy, hydropneumothorax disappeared, but hazy densities, developed in the right middle and lower lung fields, resisted to treatment. Bronchoscopy uncovered irregular tumor covering the carina and the right main bronchus, and biopsy indicated well differentiated squamous Cell carcinoma. Operation was performed on July 2, 1975. A right postero-lateral thoracotomy was used. Excision involved the lower trachea, the carina, the left main bronchus and the right lung. This was followed by direct anastomosis between the trachea and the left main bronchus. Bronchography was done on 17th postoperative day revealed good result of operation without stricture at the site ofanastomosis. About one month after the operation symptoms and signs of bronchial irritation with dyspnea developed, and these responded to respiratory care. On 82nd postoperative day, sudden dyspnea developed at night and the patient expired several hours later. Autopsy was not done and the cause of death was uncertain.

• Journal of Chest Surgery
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• 제31권8호
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• pp.804-810
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• 1998

배경: 다발성 외상환자는 교통사고, 산업재해, 우발적사고, 폭력 등의 증가로 최근 증가 추세에 있다. 다발성 외상은 심장, 폐, 대혈관 등의 흉부외상을 포함하는 경우가 많으며 이때는 환자의 생명을 위협할 수 있으므로 적절한 진단과 치료가 필요하다. 대부분의 흉부외상은 보존적 치료와 흉관 삽관술과 같은 간단한 외과적 시술 만으로 만족할 만한 치료효과를 보이지만 적절한 시기에 개흉술을 시행함으로써 환자의 생명을 구할 수 있는 경우가 있어 그 적응증 이나 시기의 판단에 있어서 경험있는 흉부외과 의사의 역할이 필요하다. 대상 및 방법: 저자는 다발성 외상 후 흉부개흉술이 필요했던 70례에 대하여 분석하였다. 환자들의 평균 나이는 35.6세 남녀비는 3.4:1이었다. 손상의 기전은 주로 교통사고, 추락사고, 자상이었다. 결과: 흉부손상의 가장 일반적인 유형은 혈흉이며, 두 번째는 횡격막 파열이었다. 환자의 60%에서 골절을 동반 하고 42.9%에서 복부손상을 37.1%에서 두부손상을 동반하고 있었다. 개흉술을 시행한 이유로는 출혈교정 혹은 지혈이 48.6%, 횡격막손상의 복구가 35.7%였으며, 폐 열상 봉합이 25.7% 였으며, 흉부 손상으로 인한 수술외에도 비장적출술(14.3%), 간엽절제술(8.6%) 간 열상 복구(5.7%)를 시행하였다. 수술후 합병증으로는 무기폐(8.6%), 창상감염(8.6%), 폐렴(4.3%)이었다. 수술후 6명의 환자가 사망하였고 수술사망율은 8.6%였다. 사망의 원인으로는 호흡부전증(2례), 급성 신기능부전증(2례), 패혈증(1례), 저혈량성 쇽(1례)이었다.

• 한국지반환경공학회 논문집
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• 제22권6호
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• pp.27-32
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• 2021

최근 기후변화로 인한 집중호우 및 태풍 등으로 농업용 저수지의 설계빈도를 초과하는 호우가 빈번히 발생하고 있어 농업용 저수지와 같은 수리시설물의 안전에 대한 관심이 증가하고 있다. 현재 국내에는 17,140여 개소의 저수지가 공용 중에 있으며, 이 중 83.87%가 1970년 이전에 건설되어 저수지의 노후화에 따른 안정성 확보를 위해 저수지 제체에 다양한 공법을 활용한 보수·보강을 실시하고 있다. 그 중 cement-bentonite 벽체를 활용한 공법은 굴착과 동시에 cement와 bentonite로 이루어진 slurry로 지중연속벽체를 시공하는 공법으로 시공방법이 간편하고 시공속도가 빠르며 굴착구역을 즉시 치환함으로 차수벽체의 균질성을 확보하여 성능이 우수하다는 장점이 있다. 그러나 이와같은 장점에도 불구하고 국내에서는 적용사례가 많지 않은 실정이다. 이에 본 연구에서는 cement와 bentonite의 혼합량을 변화시켜가며 강도변화 및 투수특성 등을 구명하여 저수지 제체의 보수·보강을 위한 cement-bentonte 벽체의 적정혼합량은 cement 200kg/m³, bentonite 60~80kg/m³인 경우가 가장 적합하다는 결론을 도출하였다.

• 센서학회지
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• 제7권3호
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• pp.154-162
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• 1998

필라멘트 모양의 백금 박막 히터 및 Bi-Sb 박막 열전퇴(thermopile)의 고온 접합부를 열차단막 역할을 하는 $Si_{3}N_{4}/SiO_{2}/Si_{3}N_{4}$ 다이아프램위에, 열전퇴의 저온 접합부를 방열판 역할을 하는 실리콘 기판에 의해 지지되는 유전체 멤버레인위에 각각 형성시켜, 열감도가 높고 교류-직류 변환오차가 작은 평면형 Bi-Sb 다중접합 열전변환기를 제작하고, fast reversed dc 방법으로 변환기의 교류-직류 변환특성을 측정하였다. 단일 bifilar 히터로 제작된 변환기의 열감도는 공기 및 진공중에서 각각 약 10.1 mV/mW 및 14.8 mV/mW였고, 2중 bifilar 히터로 제작된 변환기의 열감도는 안쪽 및 바깥쪽에 있는 히터를 입력으로 하였을 강우 공기 및 진공중에서 각각 약 5.1 mV/mW 및 7.6 mV/mW 그리고 각각 약 5.3 mV/mW 및 7.8 mV/mW로서, 기체에 의한 열손실이 거의 없는 진공중에서의 열감도가 공기중에서의 열감도보다 더 높게 나타났다. 10 kHz이하의 주파수 범위에서 변환기의 교류-직류 전압 및 전류 변환오차 범위는, 단일 bifilar 히터로 제작된 경우 공기중에서 각각 약 ${\pm}1.80\;ppm$ 및 ${\pm}0.58\;ppm$이었고, 2중 bifilar 히터로 제작된 경우 안쪽 및 바깥쪽 히터를 입력으로 하였을 때 공기중에서 각각 약 ${\pm}0.63\;ppm$ 및 ${\pm}0.25\;ppm$ 그리고 각각 약 ${\pm}0.53\;ppm$ 및 ${\pm}0.27\;ppm$였다.