• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.5
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• pp.487-495
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• 2012

The yaw control, a major part of the wind turbine, is closely related to the efficiency of electric power production and the mechanical load. The yaw error, which results from the nacelle not being appropriately aligned in the wind direction, not only decreases the power output but also reduces the lifetime of the wind turbine as a result of large fatigue loads. However, the yawing rate cannot be increased indefinitely because of constraints on mechanical loads. This paper investigates the characteristics of an active yaw control system, the basic principle of the system, and mechanical loads around the yaw axis during yawing.

• Proceedings of the Korea Society for Simulation Conference
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• 2000.11a
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• pp.186-191
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• 2000

요에 함유된 여러 성분들의 영향에 의해 다양한 정적 특성을 나타내는 요분석용 스트립의 화학적인 변화 양상을 요분석 시스템을 사용하여 요분석용 스트립의 각 항목별 각 등급별을 정성적 및 반정량적 분석을 하기 위하여 퍼지 알고리듬을 제안하고, 퍼지 분류기를 구현한 후 구현된 분류기를 검증하기 위하여 시뮬레이션 하였다. 이를 위하여 다음과 같은 연구를 수행하였다. 표준시료를 사용하여 요분석용 스트립의 분광학적 분석에 의한 퍼지 입력 변수, 퍼지 멤버쉽함수 및 퍼지규칙을 생성하였다. 그리고 구현된 분류기를 사용하여 각 항목별과 각 등급별로 평가하였다. 평가 결과 요분석용 스트립의 항목별 음성과 양성의 판별에서는 우수한 결과가 나왔으나, 정량적 분석을 위한 각 항목별 등급의 분류에서는 측정값의 오차로 인해 최고 8%의 오차가 발생하였다.

• 학교보건
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• s.25
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• pp.50-53
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• 2004

소아 요로감염이 있을시 방광요관역류가 흔히 관찰되며 만성 신우 신염과 방광요관역류와 깊은 관계가 있는 것이 알려져 있다. 발열을 동반하는 소아 요로감염시 D MSA 신주사에서 급성 신우신염의 뚜렷한 소견이 있더라도 방광요관역류가 발견되지 않는 경우가 더 많다. 하지만 신장에 신 반흔이 있을 경우에는 흔히 방광요관역류가 관찰 된다. 소아 요로감염의 처치는 신 반흔의 형성을 막는데 그 궁극적 목적이 있다 하겠다. 신생아시기 심한 방광요관역류에서 요로감염이 없이 신 이형성증으로 인한 신 반흔이 관찰되기도 한다.

• Clinical and Experimental Pediatrics
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• v.46 no.2
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• pp.173-177
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• 2003

Purpose : Recently, different results about factors affecting accurate quantitation of 24-hr urinary protein(24UP) amount using spot urine protein/creatinine ratio(PCR) have been reported. The current study was designed to evaluate correlation between 24UP amounts and PCR in children, and the effect of 24UP amounts, age, sex, and glomerular filtration rate(GFR) on this correlation. Methods : Among 94 patients who visited the department of pediatrics in Busan Paik Hospital from March 2002 to August 2002, 68 patients whose urinary creatinine excretion was ${\geq}15mg/kg/day$ were included in this study. All the patients were divided into I, II/A, B group(I : 24UP<500 mg/day, II : $24UP{\geq}500mg/day$, A : <10 years of age, B : ${\geq}10years$ of age). Pearson correlation analysis was performed between 24UP and PCR to evaluate the relationship. We defined fractional difference between 24UP and PCR, and then performed multiple regression analysis with 24UP amount, age, GFR and fractional difference. Results : There was a strong positive linear correlation between 24UP and PCR(R=0.936, P<0.0001) in all patients, and the correlation was also good in each group. Using PCR cutoff values of 0.5, the PCR provided high sensitivity, specificity, positive and negative predictive value in predicting 24UP amount ${\geq}500mg$. The factors affecting accurate quantitation of proteinuria using spot urine PCR was age, not 24UP amount, GFR or sex. Conclusion : Spot urine PCR is a useful test but has limitations in predicting 24UP amount. Therefore, it should be used only as screening method. Age-adjusted PCR cutoff values may be necessary to predict 24UP amount in children with proteinuria.

• Childhood Kidney Diseases
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• v.3 no.1
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• pp.88-94
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• 1999

Purpose : Malformation of urinary tract is among the most common of all congenital anomalies and can progress to irreversible renal damage before diagnosis due to difficulty of early diagnosis. Present study was undertaken to determine the clinical characteristics of urinary tract anomaly and to find out the most appropriate diagnostic and therapeutic measures for children with these anomalies. Methods : During the past 10 years from 1987 to 1998, review of medical records revealed 65 children with congenital anomaly of urinary tract and the following results were obtained. Results : The most common anomalies were ureteropelvic junction obstruction occuring in 26 cases ($36\%$), followed by ureteral duplication in 11 cases, renal agenesis in 10 cases and ureterovesical function obstruction in 7 cases. Complex anomaly of urinary tract was found in 8 cases and anomaly of other systems such as congenital heart disease was detected in 11 cases. The most frequent age group at the time of diagnosis was below 1 year of age constituting 39 cases ($60\%$) and male preponderance was noted as male to female ratio being 2.25:1. Presenting symptoms were urinary tract infection in 25 cases, followed by hematuria, abdominal mass, abdominal pain and voiding difficulty, etc, and in 11 cases, the anomaly was picked up by routine prenatal ultrasonography. Azotemia was noted in 9 cases and the underlying anomaly was obstructive uropathy in 4 out of these 9 cases. Surgical correction was undertaken in 38 cases (most frequently in cases of obstructive uropathy) and in 2 out off cases with obstructive uropathy in whom surgical correction was done, azotemia disappeared during follow up period of 1-5years. No new cases of deteriorating renal function appeared during follow-up period. Conclusion : In spite of high incidence of congenital malformation of urinary tract, early diagnosis is still hampered by nonspecific symptoms and signs. Therefore, in patients with symptoms such as urinary tract infection, abdominal pain and voiding problems, etc, it Is advisable to take various diagnostic tests promptly to pick up any urinary tract anomaly and to apply proper therapy in order to avoid progression to irreversible renal damage. In this regard, prenatal ultrasonography should be utilized more widely as a routine procedure to detect any urinary tract anomalies before birth.

• Childhood Kidney Diseases
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• v.5 no.2
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• pp.176-181
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• 2001

Purpose : Urinary tract infection is a common problem in children. To evaluate for reflux most authorities recommend a voiding cystourethrogram 3 to 6 weeks after the first urinary tract infection. But during the 3 to 6 weeks interval, patients may fail to show up for the scheduled VCUG and thus risk for loss of follow up. We analyzed patient's records to evaluate whether the timing of VCUG after UTI influenced the prevalence or severity of VUR. Methods : We retrospectively reviewed 213 children diagnosed with UTI from March 1997 to December 2000. These children were divided into 2 groups according to whether they had VCUG scheduled to be performed either within 1 weeks after the diagnosis of UTI (Group A) or later than 1 week after the diagnosis(Group B). We compared tile presence and severity of reflux in the 2 groups. Results : Reflux was present in $19\%$ of the patients studied within 1 week after UTI and in $18\%$ of those studied after 1 week. This difference was not statistically significant. Whereas $100\%$ of the scheduled VCUGs in the Group A were performed, only $48\%$ of those scheduled in the Group B were performed. This difference is statistically significant. Conclusion : Because there was no significant difference between the presence or severity of reflux and timing of VCUG after UTI, we suggest that a hospitalized patient with UTI should have VCUG performed before discharge. (J. Korean Sor Pediatr Nephrol 2001 ;5 : 176-81)

• The Journal of Korean Association of Computer Education
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• v.9 no.3
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• pp.67-74
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• 2006

The purpose of this study is identifying variables that affect to learners' preference toward specific e-learning programs, using an exploratory factor analysis(EFA) method. We extract common factors that explain the correlations among variables. In the result, 8 factors were identified as main influential factors: e-learning program design(1st factor), the purpose of e-learning use(2nd factor), social and cultural issues(3rd factor), demographics(4th factor), organizational needs(5th factor), impacts of e-learning(6th factor), e-learning management(7th factor), and technical issue(8th factor).

• Journal of Veterinary Clinics
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• v.29 no.4
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• pp.331-333
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• 2012

A 2-year-old, castrated male domestic short-haired cat was presented with dysuria. The physical and radiographic examinations were revealed the urethral stricture and rectourethral fistula after perineal urethrostomy (PU). A prepubic urethrostomy was performed to resolve these problems. After the treatment, the cat had normal urination and complete wound healing without any complications. This is the first case report on co-occurrence of the urethral stricture and rectourethral fistula after PU in the cat.

• Childhood Kidney Diseases
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• v.17 no.2
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• pp.42-48
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• 2013

The urinalysis is an essential part of the diagnostic work-up for kidney disease and other renal system disorders. The dipstick test allows rapid and simultaneous chemical analyses of urine, including factors such as pH, specific gravity, protein, glucose, ketones, occult blood, bilirubin, urobilinogen, nitrite, and leukocyte-esterase. The chemical reactions on dipstick are complicated and can be affected by oxidizing, reducing, and discoloring substances in the urine. Therefore, false positive and false negative results are common in dipstick testing. To obtain reliable results with the dipstick, it is necessary to collect urine cleanly and examine the urine carefully. It is mandatory to clearly understand the principles of dipstick testing to evaluate abnormal findings. If the urine dipstick results suggest hematuria, proteinuria, or urinary tract infection, microscopy of the urine should be performed to confirm the findings.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4188-4196
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• 2010

The purpose of this study is to analyze the effect of perception factors on the brand apartment for customer satisfaction by classifying perception factors into environmental factor, interior factor, brand value factor, economic factor and social factor. Variables used in this study were compiled from the survey, which was done by the people living in Pusan from Aug. 17, 2009 to Aug. 31, 2009. In the results of this study, the perception that the brand apartment had better interior quality, brand value, saleability and possibility of price rising than the common one had effects on customer satisfaction. This study analyzed the effect of perception factors on the brand apartment for post-purchase satisfaction of customer. It is expected that the results of study would help construction companies establish marketing strategies to increase customer's interest and develop the brand apartment in consideration of perception factors with a high post-purchase satisfaction.