• Childhood Kidney Diseases
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• v.11 no.1
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• pp.74-82
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• 2007

Purpose : To analyze the clinical characteristics, spontaneous resolution rate and predictive factors of resolution in children with primary vesicoureteral reflux(VUR). Methods : Between October 1991 and July 2003, 149 children diagnosed with primary VUR at Chonbuk National University Hospital were reviewed retrospectively. All of the patients were maintained on low-dose antibiotic prophylaxis and underwent radionuclide cystograms at 1 year intervals over 3 years after the initial diagnosis of VUR by voiding cystourethrogram was made. Results : The median time to resolution of VUR was 24 months and the total 3 year-cumulative resolution rate of VUR was 61.7%. The following variables were associated with resolution of VUR according to univariate analysis-; age<1 year, male gender, mild grade of reflux, unilateral reflux, congenital hydronephrosis as clinical presentation at time of diagnosis of VUR, absence of focal defects in the renal scan at diagnosis, absence of recurrent UTI, renal scars and small kidney during follow-up. After adjustment by Cox regression model, five variables remained as independent predictors of VUR resolution; age<1 yew, relative risk 1.77(P<0.05), VUR grade I+II 2.98(P<0.05), absence of renal scars 2.23(P<0.05), and absence of small kidney 5.20(P<0.01) during follow-up. Conclusion : In this study, spontaneous resolution rate of VUR, even high grade reflux, is high in infants during medical management, and it was related to age, reflux grade at diagnosis, absence of renal scars and small kidney during follow-up. Therefore early surgical intervention should be avoided and reserved for the selected groups.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.572-578
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• 2017

Haptic systems help users feel a realistic sensation when they manipulate virtual objects in the remote virtual environment. However, there are communication time delays that may make the haptic system unstable. This paper shows the relationship between communication time delay, properties of a haptic device, and the stability of the haptic system with the first-order hold method in a simulation. The maximum available stiffness of a virtual spring with the first-order hold method is larger than in the zero-order hold method when there is no time delay. However, when the communication time delay is much larger than the sampling time, the maximum available stiffness to guarantee the stability becomes the same, irrespective of the sample-hold methods. Besides, the maximum available stiffness increases in inverse proportion to the communication time delay and in proportional to the damping coefficient of the haptic device.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.39 no.5
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• pp.34-42
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• 2002

In this paper, we designed the VLSI array architecture for the high speed processing of the motion estimation used by block matching algorithm. We derived the one dimensional systolic array from the full search block matching algorithm. The data and control signals of the proposed systolic array are passed through adjacent processing element. So proposed architecture has temporal and spatial locality. The I/O ports exists only in the first and last processing elements of the array. This architecture has low pin counts and modular expandability. So the proposed array architecture can be cascaded for different block size and search range.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04c
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• pp.522-524
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• 2003

품사 결정 문제는 자연언어처리의 가장 기본적인 문제들 중 하나이며, 기계학습의 관점에서 보면 분류 문제(classification problem)로 쉽게 표현된다. 본 논문에서는 품사 결정의 모호성을 해소하기 위해서 최대 엔트로피 부스팅 모델(maximum entropy boosting model)을 이 문제에 적응하였다. 그리고, 품사 결정에서 중요한 요소 중의 하나인 미지어 처리를 위해서 특별히 설계된 일차 자질을 고려하였다. 최대 엔트로피 부스팅 모델의 장점은 쉬운 모델링인데, 실제로 품사 결정을 위한 일차 자질만 작성하는 노려만 들이고도 96.78%의 정확도를 보여 지금까지 알려진 최고의 성능과 거의 비슷한 결과를 보였다.

• The Korean Journal of Rheology
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• v.7 no.3
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• pp.192-202
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• 1995

이연구에서는 유변학 구성방정식이 나타내는 일차원 불안정성의 몇가지 예를 보였 다. 안정성 해석을 위하여 맥스웰형 미분구성방정식 Giesekus, Leonov, Larson 모델을 선택 하였다. 나타난 불안정성은 단순전단유동에서의 정상유동곡석이 무제한적 단수증가성을 위 배할 때 발생한다. 단순전단유동에 부과된 섭동하에서 Giesekus와 Larson 모델이 일정영역 의 무델계수와 전단율속도값에서 불안정 거동은 관성력을 고려하지 않은 경우에도 발생함이 증명되었다. 끝으로 이러한 불안정 거동을 개선하는 몇가지 방법을 Leonv와 Giesekus 모델 에 대하여 제시하였다.

• Proceedings of The Korean Cleft Lip And Palate Association
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• 1997.06a
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• pp.25-25
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• 1997

• 전기의세계
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• v.15 no.1
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• pp.20-22
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• 1966

현재 한전 계통내의 일차 배전전압은 3.3KV .DELTA.로 되어있고 일부분의 지역에서 5.7KV Y 또는 6.6KV .DELTA.로 승압되고 있는 실정이다. 그런데 한전 계통의 최근에 있어서의 수요의 성장율은 년 20%선을 넘고 있고 앞으로도 당분간 15-20%의 성장율이 지속될 것으로 예상되고 있다. 이와같이 급격히 성장하는 부하에 고도의 Service신속도를 유지하면서 그리고 동시에 저렴한 투자와 운전경비로서 응할수 있는 방식은 일차 배전전압을 승압하는 것이다. 여기서 논하고저 하는것은 어떤 전압으로 승압하는것이 온당할 것이냐라는 경제적 검토이다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.2
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• pp.65-69
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• 2013

In situ measurement of a primary production in East Sea, a marginal sea with a fair accessibility, is nonetheless an arduous task because of dynamic variability. In this study, we estimated the mean value of background (gross) primary production over the warm region of the East Sea based on a biogeochemical hypothesis. We propose an immiscible-shoaling hypothesis for the estimation of primary production, which assumes that primary production in the warm region occurred only by the nutrient supply through the Korea Strait. Annual primary production thus estimated is $209\;gC\;m^{-2}\;y^{-1}$, which is comparable to the satellite-based estimates of net primary production in the region. However, since this hypothesis assumes that primary production is based on only the new nutrients supplied to the system, primary production would increase by 40% if we release the assumption, and assume f = 0.6. This suggests that nutrient influx through the Korea Strait alone is more than enough to support primary production previously reported. Primary production may increase as much as two times if we considered other external perturbations excluded intentionally to estimate the background level of primary production, such as coastal upwelling, submerged ground water discharge, aeolian input, ocean dumping, and mixing by typhoons as well as the contribution of cyanobacteria that has not been quantified in the region. This implies the primary production in the warm region of the East Sea would be comparable to that of the Peru upwelling region with f = 0.6.

• Childhood Kidney Diseases
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• v.8 no.2
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• pp.129-137
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• 2004

Purpose : Nocternal enuresis is a common disorder. Tricyclic antidepressant and desmopressin have been accepted pharmacological treatment for this disorder We conducted a cooperative study to investigate the efficacy and adverse reactions of imipramine, desmopressin and combination treatment in children with primary monosymptomatic nocturnal enuresis(PMNE). Methods: Data from a large multicenter study were analysed. In the period of 8 months in 2002, the study comprised of 168 children(78 boys and 90 girls, 5 to 15 years old) with PMNE for imipramine, desmopressin or combination treatment. Before treatment a history, physical examination and laboratory tests were performed and the children were observed for 2 weeks. Response rate, adverse reactions and enuresis episodes after stopping drug administration were evaluated after 12-weeks of imipramine, desmopressin or combination of both. Results: After 4 weeks, the frequency of bed wetting in all treated patients decreased during treatment significantly Even though a 30-50%, reduction in the number of wet nights were 68.6%, 74.4% and 86.1% during 12 weeks treatment by imipramine, desmopressin and both of them respectively, there was no significant difference between them. The most common adverse reaction was decreased appetite from imipramine administration. But no serious drug-related adverse events were reported. Conclusion: Efficacy of the combination therapy of imipramine and desmopressin in PMNE appears not to be better than either drug alone. It is necessary to pay attention on account of adverse reactions during imipramine treatment even though imipramine and desmopressin were generally well tolerated.

• The Journal of the Korean bone and joint tumor society
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• v.13 no.1
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• pp.43-47
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• 2007

Sj$\"{o}$gren's syndrome is a systemic, autoimmune disorder of the exocrine glands with associated lymphocytic infiltrates of the affected glands and characteristic of dry eye and mouth. We report a case of Sj$\"{o}$gren's syndrome in which the patient presented systemic symptoms without sicca symptoms and had radiologic findings mimicking multiple skeletal metastasis and was finally confirmed with Sj$\"{o}$gren's syndrome with renal tubualr acidosis.