• Tuberculosis and Respiratory Diseases
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• v.65 no.3
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• pp.222-224
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• 2008

Spontaneous pneumomediastinum is defined as a clinical syndrome that's characterized by the presence of air in the mediastinal space, which is not due to an old previous injury or surgery. The condition is caused by a sustained increase in the intraalveolar and intrabronchial pressure with extravasated air dissecting along the perivascular spaces of the mediastinum. This is an uncommon complication of sports activity. The most common symptom is chest pain. This diagnosis should be considered for younger people who present with pleuritic chest pain or dyspnea and a characteristic crackling feel (known as subcutaneous crepitation) when touching of the skin covering the chest wall or neck, and they look otherwise well with normal vital signs. Usually no treatment is required, but the mediastinal air will be absorbed faster if the patient inspires high concentrations of oxygen. We present here a case of spontaneous pneumomediastinum that occurred during a Taekwondo match, along with a review of the relevant literature.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2000.05a
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• pp.9-11
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• 2000

국민의 영양상태가 크게 향상되어왔고 일부에서는 영양과잉과 운동부족으로 인한 비만에 대한 우려가 고조되고 있지만 최근에도 유아나 성장기 어린이들의 철분부족상태에 대한 문제점이 제기되고 있다. 외국에서는 철분 필요량이 높은 성장기 어린이나 유아들에게 영양학적 품질을 개선한 철분강화제품을 공급하기 위하여 이에 대한 연구가 오래 전부터 진행되어왔으나 여러 실험자에 의하여 행해진 실험조건, 사용된 철분염의 종류가 달라서 정확한 비교평가를 하기에는 미흡하다고 사료된다. 여러 가지 식품에서 특히 우유는 영양학적으로 완전식품이라고 하지만 철분은 거의 함유하고 있지 않아서 효과적으로 철분을 강화할 수 있는 기술은 국민영양개선 효과면에서 매우 유용하다고 사료된다. 본 연구에서는 식품첨가물로서 사용되고 있는 철분염 11종을 우유에 100 ppm수준으로 첨가하고 4$^{\circ}C$에서 저장하면서 pH, 지방산패도, 색도변화를 평가하여 우유에 사용하기 적합한 철분염을 1차적으로 선정하였다. 품질평가 결과를 종합하여 분석할 때 ferric citrate, ferric ammonium citrate, ferrous lactate가 철분강화우유 제조에 적합한 것으로 평가하였다. 또한 지금까지 철분강화식품에 일반적으로 자주 사용하고 있는 ferrous sulfate는 우유에 적합하지 않은 것으로 나타났으나 비교치로 사용하기 위하여 다음 실험에 사용하였다. 이상에서 screening된 철분염을 첨가한 우유를 HTST, LTLT으로 각각 살균하고 저장하면서 품질을 평가한 결과 HTST법이 LTLT법보다 PH, 지방산패도, 색도변화에서 나쁜 것으로 평가되었고, 철분염 종류에 따른 차이는 LTLT, HTST법에서 ferrous lactate가 우수한 것으로 나타났다. 본 연구에서 사용된 철분염 가운데에서는 ferrous lactate, ferric citrate가 유제품에 사용하기에 적합한 것으로 나타났다. 생이용성을 평가하기 위하여 우유에서 low molecular weight components(ILC)를 분리하고 철분과 복합체를 형성시킨 다음, 철분 결핍된 쥐의 소장에서 loop을 형성시켜 ILC-철분 복합체를 injection하여 철분 흡수도를 조사하였다. Ferrous lactate 100ppm에서 약 25.6%흡수되었고 ferric citrate 100ppm은 24.7%, ferrous sulfate는 19.7%흡수되었다. ILC를 첨가하지 않은 100ppm 철분염 용액은 ferrous sulfate를 제외하고는 흡수도가 감소되었다. 철분 결핍된 쥐에게 gavage 방법에 의하여 철분강화우유를 투여하였을 때 철분 25ppm 시료에서는 ferrous sulfate가 12.5%로 가장 높았고 ferrous lactate는 8.1%, ferric citrate는 6.5% 흡수되었다. 철분 100ppm수준에서는 흡수율이 낮아져 ferrous sulfate는 25ppm 시료보다 절반이하 수준이었다. Ferric citrate는 차이가 거의 없었으며 ferrous lactate는 70%수준이었다. 이상의 결과에서 철분강화우유에 사용하기 적합한 철분염은 ferrous lactate, ferric citrate였는데 특히 ferrous lactate는 제품의 이화학적 품질, 생이용성 측면 모두에서 가장 좋은 것으로 나타났다.

• Fire Science and Engineering
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• v.15 no.1
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• pp.7-15
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• 2001

This paper describes the smoke filling process of a fire field model based on a self-developed SMEP (Smoke Movement Estimating Program) codo to the simulation of fire induced flows in the atrium space (SIVANS atrium at Japan) containing smoke radiation effect. The SMEP using PISO algorithm solves conservation equations for mass, momentum, energy and species, together with those for the modified k-$\varepsilon$ turbulence model with buoyancy term. Also it solves the radiation equation using the discrete ordinates method. The result of the calculated smoke temperature containing radiation effect has shown a better prediction than the result calculated by only convection effect in comparison with the experimental data. This seems to come from the radiation effect of $H_2$O and $CO_2$ gas under smoke productions. Thus, the consideration of the radiation effect under smoke in fire should be necessary in order to get more realistic result. Also the numerical results indicated that the smoke layer is developing at a rate of about 0.1 m/s. It would take about 450 seconds after starting the ultra fast fire of 560 kW that the smoke layer move down to 1.5m above the escape level.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.5
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• pp.179-187
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• 2014

As an Accident data recorder (ADR) is a system to record a vehicle's status and dynamics information on the before and after of accident, Traffic accident investigation agencies and parts developers have a lot of interest to analyze an accident objectively and develop automotive safety devices by using real accident data, This study is to analyze an accident objectively and scientifically on the basis of traffic accident reconstruction with the use of output data of an event data recorder. This study is conducted double lane change test six times and slalom test one time as a field driving test and simulation. Based on the vehicle speed, the longitudinal and transverse acceleration, steering angle, driving path, and other kinds of information obtained from the field driving test, this study performed a simulation with PC-Crash program of reenacting and analyzing a traffic accident. The simulation was performed twice in the acceleration-steering angle input method and in the acceleration-driving path input method. By comparing the result of the field driving test with the results of the two simulations, we drew an analysis method with the optimal path reconstruction.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.3
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• pp.39-49
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• 2003

The delta operator approach and the singular perturbation technique are introduced. The former reduces the round-off error in the numerical computation. The latter reduces computing time by decoupling the original system into the fast and slow sub-systems. The aircraft dynamics consists of the Phugoid and short-period motions whether its model is longitudinal or lateral. In this paper, an approximated solutions of lateral dynamic model of Beaver obtained by using those two methods in compared with the exact solution. For open-loop system and closed-loop system, and approximated solution gets identical to the exact solution with only one iteration and without iteration, respectively. Therefore, it is shown that implementing those approaches is very effective in the flight dynamic and control.

• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.370-377
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• 2007

The spawning host selection and adaptive characteristics in life history were investigated for Sarcocheilichthys nigripinnis morii which has similar habit of spawning with acheilognathine fishes. The fertilized eggs of the species were found in the mantle cavity of Corbicula papyracea and C. fluminea among the bivalves collected from same locality, meaning the species specific host selection for the spawning. We considered that the differences in the status of expanding egg membrane after hydration, fewer number of eggs settled into the mantle cavity and having eleutheroembryo with developed organ would be some evidences of specific reproductive strategy for this species. But the status of developed surface blood circulation was thought to be a compensation for the parasitism. The pigmentation of melanopore delayed to late embryo and the spot on the caudal region was a characteristics of this species appeared in the early life history.

• Journal of Chest Surgery
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• v.29 no.2
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• pp.239-243
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• 1996

Chest wall reconstruction Is difficult because of the physiological and anatomical functions of thoracic cavity where the thoracic cavity must be stabilized in order to prevent paradoxical motion, and adequate protection must be provided to the mediastinal structures. A 37-year-old male patient with full-thickness defect on the left anterior thoracic cavity due to traffic accident was treated. Emergency operation was performed for debridement and bleeding control, and on postoperative 25 days, chest wall reconstruction was performed as a second-stage operation. Left anterior chest wall was reconstructed with latissimus dorsi myocutaneous flap which had thoracodorsal arterial pedicle, and split-thickness skin grift from the left thigh was done. After chest wall reconstruction, spontaneous self-respiration was possible without ventilatory support. The pulmonary function test performed at postoperative 3 months revealed 80% of predicted values (FVC, FEV1.0). The postoperative result of chest wall reconstruction using latissimus dorsi myocutaneous flap was excellent anatomically, physiologically and aesthetically.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.14 no.2
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• pp.168-173
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• 2014

Vascular Ehlers-Danlos syndrome (vEDS) is an autosomal dominant disorder caused by a mutation of the type III collagen (COL3A1). The manifestation of vEDS can be seen in skin, joints, blood vessels, and internal organs. The diagnosis of vEDS often is missed until the patient presents with a life-threatening complication such as spontaneous arterial rupture or bowel perforation. We report a 16-year-old male who had recurrent right thigh hematoma after simple exercise and minor trauma, respectively. He had a history of surgery due to spontaneous colon perforation at his age of 11 years. Gene test of COL3A1 revealed a novel mutation c.2931+dupT.

• Korean Journal of Microbiology
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• v.31 no.4
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• pp.261-266
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• 1993

A new methyltrophic bacterium which utilizes methanol as a sole source of carbon and energy was isolated from soil. It was Gram-negative, nonmotile, nonspore-forming rod, and strictly aerobic bacterium. Catalase and oxidase activities were present. Nitrate was reduced to nitrite. Vitamins and other growth factors were not required. Generation time was 1.6 hr under the optimal condition. The isolate assimilated methanol via the ribulose mono-phosphate pathway (Enter-Doudoroff varient) and did not have .alpha.-ketoglutarate dehydrogenase. It assimilated ammonia through glutamate dehydrogenase. The guanine plus cytosine content of the DNA was 61.0 mol%. The celular fatty acid composition was primarily straight-chain saturated $C^{16 : 0}$ acids (palmitic acids) and unsaturated $C_{16 :1}$ acid (palmitoleic acids), and the isolate also contained two unidentified $C_{17}$ branched fatty acids. The major ubiquinone was Q-8, and Q-6 and Q-7 were present as minor components. Phosphatidylethanolamine and phosphatidylglycerol were predominantly present, and diphosphatidyglycerol was also detected. Based on the physiological and biochemical properties, the isolate was assigned to a novel species of the genus Methylobacillus, Methylobacillus methanolovorus sp. nov.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.4
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• pp.296-301
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• 2001

Electro-Rheological (ER) fluids belong to a class of colloidal suspensions whose global characteristics can be controlled by the imposition of an appropriate external electrical field upon the fluid domain. The ER fluids for smart hydraulic system are a class of colloidal dispersion which exhibit large reversible changes in their rheological behavior when subjected to external electrical fields. This paper presents experimental results on mechanical properties of an ER fluids subjected to electrical fatigues. As a first step, ER fluid is made of methyl cellulose(MC) ingredient choosing 25% of particle weight-concentration. Following the construction of test for mechanical properties of ER fluid, the shear stress, dynamic yield stress and current density of the ER fluids are experimentally distilled as a function of electric field cycles. The mechanical properties test of operated ER fluids are distilled and compared with those of unused ER fluids.