• Proceedings of the Acoustical Society of Korea Conference
• /
• 1998.06e
• /
• pp.137-140
• /
• 1998

본 논문은 비균일 분포 수동형 견인 배열 센서를 사용하여 입사각 추정은 물론, 도플러 주파수를 동시에 추정해내기 위한 기법을 제안한다. 균일 선형 센서 배열을 사용하는 전통적인 수동형 견인 센서 배열 처리기법은 센서간의 등 간격구조 및 단순한 표본 과정에 기인하여 활용 분야의 한계성을 가지며, 주된 응용 분야가 방사된 음향신호의 입사각을 추정하는 데만 국한되어 사용될 수 있다는 문제점을 내포하고 있다. 본 논문은 이러한 제한성을 극복하고 방사 신호들의 개별적인 입사각 및 도플러 주파수의 동시 추정이 가능한 새로운 형태의 수동형 견인 배열 센서 처리 기법을 제안한다.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2012.05a
• /
• pp.422-425
• /
• 2012

스트리밍 비디오 시스템의 QoS에 관한 기존 연구가 네트워크의 관점에서 비디오 스트림의 전송률을 조절하는 기법위주로 이루어져 균일한 화질을 제공받고자 하는 사용자에게 VBR 스트리밍 비디오의 장점을 제공하기 어려웠다. 본 논문에서는 스트리밍 비디오 시스템에서 클라이언트의 대역폭 변화에도 사용자에게 균일한 화질을 제공하기 위하여 CBR 스트리밍 비디오의 장점을 VBR 스트리밍 비디오에 적용하는 비디오 코덱을 설계한다.

• Proceedings of the Korean Society of Sericultural Science Conference
• /
• 2003.04a
• /
• pp.50-50
• /
• 2003

최근 누에동충하초 재배농가에서 대량발생한 오염균 중 일종은 누에치사 및 부정형 자실체를 발생시켜 생산성 감소시키고 상품성을 저하시켜 농가에 많은 피해를 가져오므로, 이상누에로부터 균을 분리하고 재접종 시험한 결과 원인균은 Paecilomyces farinosus(Holm ex S.F. Gray) Brown ＆ Smith로 동정되었으며 특성은 다음과 같다. (중략)

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
• /
• 2005.10a
• /
• pp.294-296
• /
• 2005

Lactobacillus 및 Streptococcus 속의 유산균을 사용하여 유산균이 가지는 항산화 효과를 측정하였다. DPPH 법을 사용하여 전자공여능을 측정한 결과, L. casei가 43.54%로 가장 높았으며 L. acidophilus는 33.43%, 그리고 S. thermophilus가 7.1%로 가장 낮은 항산화 효과를 나타내었다. 유산균 파쇄액의 SOD 유사활성은 L. acidophilus가 15.68%, L. casei는 19.86%, S. thermophilus는 49.3%로 전자공여능의 측정 결과와는 달리 S. thermophilus가 가장 뛰어난 SOD 유사활성을 나타내었다.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2007.11a
• /
• pp.175-176
• /
• 2007

대면적 플라즈마 스퍼터링 시스템에서 가스 분배 구조의 변화가 시스템의 압력 균일도에 미치는 영향을 3차원 수치 모델을 통하여 연구하였으며 2 line parallel internal antenna의 경우에 대해서 플라즈마 균일도를 drift diffusion approximation을 이용하여 계산 하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2007.04a
• /
• pp.97-98
• /
• 2007

$SiH_4-Ar-O_2$ ICP-CVD에서 증착된 $SiO_2$막의 두께 균일도를 개선시키기 위해 반응가스 주입구의 위치가 두께 균일도에 영향을 주었을 것으로 예상하고, CFD-ACE를 이용하여 2차원 모델링을 하여 최적데이타를 도출하였다.

• Pediatric Infection and Vaccine
• /
• v.4 no.1
• /
• pp.79-89
• /
• 1997

Purpose : Neonatal bacterial meningitis is the disease which clinical manifestations are nonspecific and several neurologic complications may occur. We studied neonatal bacterial meningitis, particularly in treatment and prognosis according to causative organisms -gram positive and gram negative bacteria- to assist in treatment of neonatal bacterial meningitis. Methods : We analysed twenty-four cases retrospectively who had been admitted in NICU or pediatric ward in Chung-ang Gil hospital from Jan. 1991 to Jun. 1996, and who had proven causative organisms in culture or latex agglutination[n test in CSF. Results : 1) The ratio of male to female was 2.4: 1. The mean birth weight and gestational age in cases with gram positive bacterial meningitis were $2.91{\pm}0.79kg$ and $38.4{\pm}2.74$ weeks and those in cases with yam negative bacterial meningitis were $3.30{\pm}0.90kg$ and $37.7{\pm}3.33$weeks respectively. There was no significant difference between the two groups. 2) The perinatal predisposing factors were pematurity, mecoinium staining amnionic fluid, matemal diabetes and pregnancy-induced hypertension, etc. The clinical manifestations Were fever, seizure, poor oral intake and fontanel bulging, etc. There were eleven cases with early onset bacterial meningitis(four cases by gram positive bacteria, seven cases by gram negative bacteria), and thirteen cases with late onset bacterial meningitis(seven cases by gram positive bacteria, six cases by gram negative bacteria). There was no significant difference between the two groups in terms of onset. 3) There were eleven cases with yam positive bacterial meningitis and they were coagulase-negative staphylococci(three cases), group B streptococci(three cases), Staphylococcus aureus(two cases), Streptococcus viridans(two cases), and enterococci(one case). And there were thirteen cases with gram negative bacterial menir gitis and they were Escherichia coli(seven cases), Klevsiella pneumoniae(three cases), Pseudomonas aeruginosa(one case), Acinetobactor(one case) and Enterobacter(one case). 4) The initial CSF WBC counts in cases with yam negative bacterial meningitis were significantly higher than those in cases with gram positive bacterial meningitis but the CSF protein and glucose levels were no significant difference in the two groups statistically. 5) The number of cases with abnormal findings in brain ultrasonography was seven in gram positive bacterial meningitis and ten in gram negative bacterial meningitis. 6) There were relatively high sensitivity to penicillin derivatives, the first generation cephalosporin and vancomycin in gram positive bacteria and to the third generation cephalosporin and amikacin in gram negative bacteria. 7) The mortality rate was 20.8%(5 cases were expired or discharged hopelessly). There was no significant difference between the two groups in prognosis. Conclusions : We recommend active treatment in noenatal bacterial meningitis to improve prognosis because the prognosis is poor.

• Korean Journal of Soil Science and Fertilizer
• /
• v.33 no.4
• /
• pp.292-301
• /
• 2000

To make a better use of the beneficial bacterial inoculants in the agricultural practice, dry forms of bacterial fertilizer or pesticides are prepared with carrier materials. During the drying process of bacterial inoculant, most of the cells face a severe osmotic pressure and dehydration, and die off. Our study describes the effect of osmoprotectants such as trigonelline and trehalose on the survival of bacterial cells in high salt concentration and drying conditions. A fluorescent Pseudomonas, strain SSL3, used in this study, could grow in high salt concentration of upto 5% but the cells could not overcome the growth retardation at over 7% of salt concentration. The addition of trigonelline, even on small amount, in liquid medium containing 4% NaCl was detrimental to the cell. However, the addition of trehalose of upto 10 mM to the liquid medium containing 4% NaCl, enhanced cell growth. The cell growth was retarded when 150mM trehalose was added to the medium. Upon dry formulation of cells, trehalose was added. And the dry cells were inoculated into the soil to determine the effect of osmoprotectants on the survival of the cells. The survival of the cells, both in wet or dry soil, was improved by the addition of trehalose during the dry cell formulation. The positive effect of trehalose on the cell survival at $-20^{\circ}C$ and $-70^{\circ}C$ was oven more pronounced. The FTIR (Fourier transformation infra-red) spectroscopic analysis showed that the change of the 2nd amide group was reduced by adding trehalose to the medium containing 4% NaCl. These results suggest that trehalose can protect the cell membrane from dryness or high concentration of salt, thereby diminishing the sudden change of the protein structure of the cell membrane and, as a consequence, improving the cell survival.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.4 no.1
• /
• pp.18-27
• /
• 2001

Purpose: The aims of this study are to investigate the effect of the eradication of H. pylori on histological change of gastric mucosa in children with H. pylori gastritis and to determine whether the histological grading by the Sydney system is valuable in predicting the effect of treatment. Methods: 1) Histological scores by the Sydney system and the endoscopic characteristics were assessed before and at least four weeks after anti-H. pylori therapy in 42 children with H. pylori gastritis. 2) In 32 children treated with omeprazole, amoxicillin and clarithromycin (OAC), pretreatment histological scores and endoscopic findings were compared between the eradicated and the noneradicated to evaluate their predictive value for the successful eradication. Results: 1) In the eradicated (27 cases), nodular gastritis significantly decreased from 89% to 63% (p<0.05). There was an significant improvement in the mean activity score from 2.06 before treatment to 0.24 after treatment (p<0.01). The mean inflammatory score also improved from 2.61 before treatment to 1.89 after treatment (p<0.05). Lymphoid follicles significantly decreased from 48% to 15% (p<0.05). Epithelial damage improved in all 4 cases. But in the noneradicated (15 cases), there was no significant change in the frequency of nodular gastritis, the mean activity score, the mean inflammatory score and the frequency of the lymphoid follicles. 2) In 32 children treated with OAC, there was a tendency that the higher was the pretreatment score of the bacterial density, the lower was the eradication rate of H. pylori (p=0.072). Conclusion: The loss of the polymorphonuclear cell infiltration is the most prominent histological change after successful eradication. There may be negative correlation of the grade of the bacterial density with the success rate of the anti-H. pylori therapy.

• Tuberculosis and Respiratory Diseases
• /
• v.47 no.6
• /
• pp.747-756
• /
• 1999

Background: Acid-fast stain and cultures for diagnosis of pulmonary tuberculosis are primary and essential method, but have their limitation : low sensitivity and time consuming. The objective of this study is comparison of amplified Mycobacterium tuberculosis direct test(MTD) by the conventional AFB smears and cultures in the detection of Mycobacterium tuberculosis in respiratory specimens. Methods: During the period between November, 1997 and May, 1998 a total of 267 respiratory specimens (sputum 173, bronchial washing 94) from 187 patients suspected pulmonary tuberculosis were subjected to AFB smears, cultures and MID test. MID is based on nucleic acid amplification. We compared the MID with 3% Ogawa culture method. In positive AFB smear and negative MID specimen, positive culture identification between nontuberculous mycobacterium and M.tuberculosis was assesed by using Accuprobe M.tuberculosis complex probe. In negative AFB smear and negative AFB culture, MTD results are assessed by clinical follow-up. Results : 1) Compared with culture in sputum and bronchial fluid specimens, sensitivity and specificity of MTD in positive AFB smear is 79.7% and 20.0%, sensitivity and specificity of MTD in negative AFB smear specimens is 75.0% and 79.7%. 2) Discrepant analysis is assessed by clinical follow-up and other specimen results beyond study. Culture negative but MTD positive specimens were proved to be true positive and gave MTD sensitivity 79.2%, specificity of 84.4%, positive predictive value 80.5% and negative predictive value 83.2%. 3) 14 out of 31 specimens in negative AFB smear, negative AFB culture and positive MTD showed pulmonary tuberculosis diagnosed on clinical follow-up and sensitivity is 45.2%. 4) 2 out of 13 specimens in positive AFB smear, positive AFB culture and negative MID diagnosed as non tuberculous mycobacterium by Accuprobe culture. Conclusion: This study suggested that MID in respiratory specimens is simple and rapid diagnostic method, but considered adjuvant method rather than replace the conventional AFB smear and culture.