• 한국군사과학기술학회지
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• 제7권4호
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• pp.53-60
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• 2004

In this paper, the radar antenna of navigation radar on helicopter was suggested to Ka-band lens antenna. It is type of the streamlined convex lens to reduce the air resistivity when helicopter was navigated. Although aperture area is smaller than the standard antenna just like horns, the gain is higher and beamwidth is smaller than standard horns. We made the lens by using maximum flare angle of the horn and dielectric constant of the lens. As a result, when aperture diameter was 280mm and focal length was 145mm, the return loss -21.25dB, the gain was 32.2dBi, E and H beamwidth was $1.8^{\circ}$(E-plane), $1.4^{\circ}$(H-plane), nearly $1.5^{\circ}$, and side-lobe level was -18.4 dB(E-plane), -19.5dB(H-plane) lower were presented. So this suggested type can be used for the radar antenna of navigation radar on helicopter, and it will possible just a little some sidelobe suppression by using the choked horn as a feeder horn.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1312-1316
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• 2007

Strip casted and rolled magnesium sheet is become exiting material for car manufacturer, due to its better formability and specific strength compare with conventional extruded sheet. TWB technology was attractive for car body designer, because it saves the weight of the car without strength loss. In this study, the laser welding performance of magnesium sheet was investigated for Mg TWB panel manufacturing. The material was strip casted and rolled magnesium alloy sheet contains 3 wt% Al and 1 wt% Zn (AZ31). Lamp pumped Nd:YAG laser of 2kW was used and its laser light was delivered by optical fiber of 0.6mm core diameter to material surface with focusing optics of 200mm focal length for TWB welding. The microstructure of weld bead was investigated to check internal defects such as inclusion, porosity and cracks. Also mechanical properties and formability were evaluated for press forming of car body. For the results, there was no crack but inclusion or porosity on weld at some conditions.The tensile strength of weld was over 95% of base metal. Inner and outer panel of engine hood were press formed and assembled at elevated temperature.

• 센서학회지
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• 제27권5호
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• pp.300-305
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• 2018

The uncooled microbolometer thermal sensor for low cost and mass volume was designed to target the new infrared market that includes smart device, automotive, energy management, and so on. The microbolometer sensor features 80x60 pixels low-resolution format and enables the use of wafer-level vacuum packaging (WLVP) technology. Read-out IC (ROIC) implements infrared signal detection and offset correction for fixed pattern noise (FPN) using an internal digital to analog convertor (DAC) value control function. A reliable WLVP thermal sensor was obtained with the design of lid wafer, the formation of Au80%wtSn20% eutectic solder, outgassing control and wafer to wafer bonding condition. The measurement of thermal conductance enables us to inspect the internal atmosphere condition of WLVP microbolometer sensor. The difference between the measurement value and design one is $3.6{\times}10-9$ [W/K] which indicates that thermal loss is mainly on account of floating legs. The mean time to failure (MTTF) of a WLVP thermal sensor is estimated to be about 10.2 years with a confidence level of 95 %. Reliability tests such as high temperature/low temperature, bump, vibration, etc. were also conducted. Devices were found to work properly after accelerated stress tests. A thermal camera with visible camera was developed. The thermal camera is available for non-contact temperature measurement providing an image that merged the thermal image and the visible image.

• Journal of Yeungnam Medical Science
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• 제13권2호
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• pp.360-366
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• 1996

Pure primary hepatic rhabdomyosarcoma in adult is very uncommon. There have been only five previous case of primary rhabdomyosarcoma of the adult liver. A case of hepatic rhabdomyosarcoma was diagnosed in a 52 year-old female. She was admitted to the hospital due to the epigastric pain and weight loss. A CT scan of the abdomen showed a large hypodense mass with focal calcification occupies most of the both lobes of the liver. The liver biopsy showed massive liver tumor composed entirely of oval shaped cells showing light microscopic and immunohistochemical evidence of rhabdomyoblastic differentiation. We report a case of hepatic rhabdomyosarcoma with review of literature.

• Journal of Yeungnam Medical Science
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• 제34권1호
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• pp.140-145
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• 2017

Glomerulonephritis (GN) is sometimes associated with infective endocarditis (IE). Bartonella endocarditis is difficult to diagnose because it is rare and cannot be detected by blood culture. This is the first report of cytoplasmic anti-neutrophil cytoplasmic antibody-positive subacute endocarditis-associated GN caused by Bartonella infection in South Korea. A 67-year-old man was hospitalized due to azotemia. He complained of weight loss and anorexia for 6 months. A diagnosis of IE was made based upon echocardiographic detection of vegetations on the mitral and aortic valves and a Bartonella antibody titer of 1:2,048. Renal histology identified focal crescentic GN. Azotemia and proteinuria improved after doxycycline and rifampin treatment combining with steroid therapy.

• Journal of Korean Neurosurgical Society
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• 제29권6호
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• pp.822-825
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• 2000

Lymphocytic infundibuloneurohypophysitis is a rare inflammatory disorder, which may be caused by autoimmune response, affecting the infundibulum and the posterior lobe of the pituitary gland. The authors present a 15-year-old man with central diabetes insipidus, whose sellar magnetic resonance imaging (MRI) showed a focal thickening of the infundibulum and loss of high signal of the normal neurohypophysis on T1-weighted images. The histopathological diagnosis was lymphocytic infundibuloneurohypophysitis. When a patient presents with central diabetes insipidus and infundibular thickening on brain MRI, this entity should be included in the differential diagnosis though it is very rare. The significance of this entity in treatment is that it is basically not a surgical one, and surgery is needed only for tissue diagnosis. Symptomatic treatment and observation make it regress spontaneously.

• Tuberculosis and Respiratory Diseases
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• 제39권1호
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• pp.89-94
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• 1992

저자들은 전신성홍반성낭창에서 신장염에 이어 급성 폐렴이 발생하여 이의 악화로 사망한 환자를 경험하였기에 문헌고찰과 함께 보고하는 바이다.

• 대한한의학방제학회지
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• 제17권1호
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• pp.99-111
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• 2009

Rheumatoid arthritis is characterized by focal loss of cartilage due to an up-regulation of inflammatory pathways, which produce pro-inflammatory mediators, such as interleukin-1(IL-1), tumour necrosis factor alpha($TNF-\alpha$), prostaglantin, and nitric oxide(NO). We investigated the anti-arthritic effects of water extracts from Pellodendri cortex and Atractylodis rhizoma in vitro and in vivo. Each extract suppressed the production of inflammatory mediators(NO, $IL-1\beta$, $TNF-\alpha$, and prostaglandin $E_2$) and the expression of inducible NO synthase and cyclooxygenase-2 in lipopolysaccharide-stimulated macrophages in a dose-dependent manner. These suppressive effects were synergistically increased by their combination. The same results were also observed in the rat osteoblast sarcoma cell line ROS17/2.8 stimulated with $IL-1\beta$, $IFN-\gamma,$ and $TNF-\alpha$. Moreover, the combination of these water extracts significantly suppressed collagen-induced mouse arthritis. These results suggest that the combination of water-extractable components of Pellodendri cortex and Atractylodis rhizoma may be useful for therapeutic drugs against rheumatoid arthritis, probably by suppressing the production of inflammatory mediators.

• Clinical and Experimental Pediatrics
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• 제54권8호
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• pp.322-328
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• 2011

Nephrotic syndrome (NS) is one of the most common glomerular diseases that affect children. Renal histology reveals the presence of minimal change nephrotic syndrome (MCNS) in more than 80% of these patients. Most patients with MCNS have favorable outcomes without complications. However, a few of these children have lesions of focal segmental glomerulosclerosis, suffer from severe and prolonged proteinuria, and are at high risk for complications. Complications of NS are divided into two categories: disease-associated and drug-related complications. Disease-associated complications include infections (e.g., peritonitis, sepsis, cellulitis, and chicken pox), thromboembolism (e.g., venous thromboembolism and pulmonary embolism), hypovolemic crisis (e.g., abdominal pain, tachycardia, and hypotension), cardiovascular problems (e.g., hyperlipidemia), acute renal failure, anemia, and others (e.g., hypothyroidism, hypocalcemia, bone disease, and intussusception). The main pathomechanism of disease-associated complications originates from the large loss of plasma proteins in the urine of nephrotic children. The majority of children with MCNS who respond to treatment with corticosteroids or cytotoxic agents have smaller and milder complications than those with steroid-resistant NS. Corticosteroids, alkylating agents, cyclosporin A, and mycophenolate mofetil have often been used to treat NS, and these drugs have treatment-related complications. Early detection and appropriate treatment of these complications will improve outcomes for patients with NS.

• 성인간호학회지
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• 제15권1호
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• pp.56-66
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• 2003

Purpose: The purpose of this study is to describe the psychological aspects of experiences of men living in a homeless shelter in Seoul. This study focused on understanding about the life of the homeless in the shelter by Phenomenological method. Method: The participants in this study were seven men who are living in a homeless shelter in Seoul. The following data were collected though the in-depth interviews and analyzed by the Phenomenological analytic method of Giorgi. Result: There are five focal significances about the life of the homeless. (1) Unplanned Life : Difficult life comes from outside situation, Freedom, The acceptance of unconsciousness life, Laziness, Unreliability, The dissolute life, No purpose to life, Relying on drinking, (2) Self-rationalization : Feeling of defeat, Give up, Desire for a support system, Lack of willingness, Anxiety, Chivalry, Falsehoods, (3) Superficial Interpersonal Relationships : Ignorance, Pressure, Discord, Hiding from one anther, avoidance. (4) A sense of devestation : Negative perspective, Mental weakness, Difficulties in employment, ambivalance with social structure, The place to escape, Complaining against the opposite sex, Sense of regret, Lack of relationship with family, The lack of self-confidence, Loss of volition (5) The Hope of new life : Realization, Desire for change, Dreaming of married life, Dependence in God Conclusion: The conclusion of this study shows that the men in the shelter had various psychological reasons for being in the homeless shelter. Further studies need to be done to validate this information and formulate ways to assist these men with their psychological needs.