• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.3
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• pp.58-67
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• 2019

The low-voltage connection box used as a low-voltage transmission line of KEPCO is intended to branch or connect to an underground line. In comparison with the utility considering the aesthetics of the distance, and safety measures are needed. In this paper, temperature and humidity, $CO_2$, water level, acceleration, and vibration sensor are installed inside the underground low voltage handhole, and the sensor data is transmitted to the ground using the Zigbee module. Antenna (Bolted Antenna) for communication with the ground was proposed and the data reception through it was confirmed. In the LF mode and the HEX mode, the transmitted data was confirmed to be a perfect reception success rate. In the case of the bolted antenna, the difference between the ground state and the underwater state was observed as a result of the experiment in the environmental environment. However, It was judged that reception sensitivity was sufficient for communication. The received data could be confirmed through PC based GUI.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.103-103
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• 2016

최근 기후변화에 따른 집중호우로 도시홍수의 피해가 급격히 증가하고 있다. 특히 인구가 밀집하고 교통량이 많은 대도시의 경우 동일한 호우에 대하여 녹지나 농경지 등에 비해 그 피해가 더 심각하다. 일반적으로 홍수 피해의 직접원인은 외수로 인한 피해와 내수로 인한 피해로 크게 구분할 수 있다. 외수피해는 주로 소하천 및 지천의 범람, 제방의 붕괴 등으로 발생한 것이며 내수피해는 배수로, 하수도 및 펌프장의 내수배제능력 부족이 주된 원인이다. 따라서 도시홍수를 효과적으로 방어하기 위해서는 우선적으로 내배수시설의 성능개선이 선행되어야 할 필요가 있다. 이러한 내배수 시설의 성능 개선을 위해서는 현재 기 설치되어 있는 빗물펌프장의 설계 및 내배수 효율에 대한 성능평가가 필요하다. 하지만 현재 국내 펌프설계기준에는 빗물펌프장의 설계 및 운영에 대한 구체적인 성능 평가 방법이 제시되어 있지 않은 실정이다. 만약, 펌프 흡입수조 및 흡입파이프의 형상이 적절하게 설계되지 못한다면 물이 파이프 입구로 부드럽게 흡입되지 못하고 볼텍스 및 스월이 발생하게 된다. 이러한 볼텍스 및 스월은 펌프 입구 쪽으로 물 뿐 아니라 공기를 함께 흡입시킴으로써 펌프의 효율저하, 소음, 진동을 발생시키며 펌프 파손의 원인이 될 수 있다. 따라서 펌프를 설치하기 전 펌프 설치 후에 발생되는 펌프 흡입부 주변의 흐름특성 변화 및 흐름특성이 구조물에 미치는 영향 등을 고려하기 위하여 수리모형실험이 필요한데, 수리모형실험은 많은 시간과 비용이 들어가기 때문에 이를 대체할 수 있는 방안이 요구된다. 그런 이유로 최근에는 수리모형실험 대신 수치모의를 이용하는 경우가 많다. 수치모의의 결과는 수리실험의 결과와 비교, 검증을 거쳐 신뢰성을 얻는다. 본 연구에서는, 3차원 수치모형의 다양한 난류모델을 이용하여 흡입파이프로 물이 유입될 때 흡입부 내, 외의 수심 별 유속 변화를 분석하고, 그 결과를 이용하여 FLOW 3D 모형의 검증을 수행하였다.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.547-552
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• 2022

In this study, shape-based track management by analyzing track irregularity was studied in terms of force-based track irregularity analysis by numerical analysis of wheel-rail interaction force using by the measured vertical irregularity. The effect of the vertical irregularity of the track due to the difference in track types on the wheel-rail interaction force and the track acceleration in the connecting section of the sleeper floating track and the direct fixation track on concrete bed were analyzed. As the results of this study, the measured vertical irregularity was directly affect the vertical wheel load (the wheel-rail interaction force) and the rail acceleration, and it has been demonstrated to change consistently. In this study, the adequacy and necessity of the force-based track irregularity analysis method was verified based on the wheel-rail interaction analysis using the the measured vertical irregularity.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.11a
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• pp.648-651
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• 2010

웰빙의 바람을 타고 이제 자신의 건강을 관리하는 사람들이 많아지고, 흡연에 대한 좋지 않은 인식이 높아지면서 금연의 열풍이 강하게 불고 있다. 하지만 금연을 한다고 해도 주위의 담배연기는 우리 몸의 건강을 해치기 때문에 담배연기로부터 해방되기는 매우 어렵다. 실제로 흡연하는 배우자를 가진 사람은 그렇지 않은 사람에 비해 심장병 발생률은 40%, 폐암 발생률은 30%가 더 높다. 따라서 본 논문에서는 간접흡연이 인체의 조음기관에 미치는 영향을 분석하기 위해 간접흡연에 따른 음성의 변화를 측정하고 비교, 분석하는 실험을 수행하였다. 이를 위해 간접흡연 전과 후의 음성을 수집하여 음성분석학적 요소 기술 중 Pitch, Jitter, Shimmer 등의 성대 진동 요소를 적용하고 인체 내의 공명기관을 분석하는 Formant를 적용하여 실험을 수행하여 간접흡연이 음성에 미치는 영향을 연구하였다.

• The Journal of the Acoustical Society of Korea
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• v.43 no.3
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• pp.277-284
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• 2024

This study proposes a method to predict noise reduction based on noise-reduction measures, using harmonic response analysis, for transformer design. The dynamic elastic coefficients of the components comprising the actual transformer were determined by manufacturing the materials of the transformer components into simple-shaped specimens, followed by a comparison of the modes between the experiments and the analyses. A finite element model of the transformer was implemented, and harmonic response analysis was performed by deriving the exciting force of the transformer. Subsequently, the theoretical sound power level of the transformer was derived from the results of the harmonic response analysis. Finally, noise reduction measures were established, and the noise reduction amounts were compared between the experiments and the analyses, before and after applying the measures. Through the comparison and analyses of the noise reduction measures, it was confirmed that the trends in the experiments and analyses matched.

• Childhood Kidney Diseases
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• v.11 no.1
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• pp.41-50
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• 2007

Purpose : Dialysis in children with chronic renal failure presents with many difficulies. The purpose of this study is to find an improved method in chronic dialysis in infants and children less than 2 years of age by analyzing the experience with 10 cases. Methods : A retrospective review of the medical records of 10 patients(6 boys and 4 girls) was conducted. The patients had chronic renal failure and underwent chronic dialysis at Samsung medical center from March 1999 to February 2007. Results : At Initiation of dialysis, the median age was 3 months old(22 days-20 months), the median body weight was 3.75 kg(2.2-10.3 kg), and the median serum creatinine level was 4.3 mg/dL(2.0-11.4 mg/dL). The median duration of dialysis was 29.5 months(3-62 months). Dysplastic kidney disease was the most common underlying renal disease. Two patients were treated with hemodialysis, 4 patients with peritoneal dialysis, and 4 patients eventually switched dialysis modality. Nine of the 10 patients took erythropoietin and anti-hypertensive drugs. At the end of the follow up period, 1 patient received kidney transplantation, 2 patients died due to sepsis, and 5 patients were treated with peritoneal dialysis. Two patients were lost to follow up. The most common complication of dialysis was infection. Achieving vascular access and maintaining proper catheter function were the most important factors in treating patients with hemodialysis. The growth status of patients was aggravated after 6 month of dialysis but improved after 1 year of dialysis. Patients showed better growth on peritoneal dialysis than hemodialysis. Conclusion : Chronic dialysis can be performed successfully in infants and children under 2 years of age. Vascular access was the main limitation of hemodialysis, and infection was the common problem in both hemodialysis and peritoneal dialysis. To improve the patients survival rate and quality of life, major efforts should be directed toward the prevention of infection and preservation of catheter function. (J Korean Soc Pediatr Nephrol 2007;11:41-50)

• Proceedings of the KOR-BRONCHOESO Conference
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• 1983.05a
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• pp.8.2-9
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• 1983

Recently, the laryngomicrosurgery has been done for the removal of benign laryngeal mass and for the improvement of voice. For the evaluation of the effect of the treatment, there must be any objective method such as aerodynamic study, vocal fold vibration study, acoustic analysis, psycho-acoustic evaluation and the neuro-muscular study. The authors evaluated the phoniatric effect of the laryngomicrosurgery for the patients of 15 laryngeal polyps and 9 laryngeal nodules, who received pre-op. and post-op. vocal function study from Jun. 1981 to Mar. 1983. The results obtained were as follows ; 1) The post-op. mean value of the maximum phonation time was increased 40 % in the unilateral polyps, 62 % in the bilateral nodules and 18 % in the unilateral nodules. 2) The post-op. mean value of the phonation quotient was decreased 25 % in comparison with pre-op. value in the case of the bilateral polyps, 26 % in the unilateral polyps, 55 % in the bilateral nodules and 12 % in the unilateral nodules. 3) The post-op. mean value of the mean air flow rate was decreased 27 % in comparison with the pre-op. value in the case of the bilateral polyps, 25 % in the unilateral polyps, 65 % in the bilateral nodules, 25 % in the unilateral nodules. 4) The glottic chink of the 10 cases of polyps among the 11 cases were disappeared, and the glottic chink of the 5 cases of nodules among 7 cases were also disappeared after surgery. 5) The pre-op. hoarseness of the 10 cases of polyps among the pre-op. hoarseness of the 11 cases of polyps were changed to clear and the 3 cases of nodules were also changed to clear.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.123-129
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• 2003

This study is to investigate consequent nutrient intake status, Influences of body mass index (BMI) and serum lipid composition, and fat distribution on the cocoon hydrolysate, green tea leaves and dietary fiber supplementation. During 2 months of this research (April to May, 2002), 47 women aged 20 yr-30 yr (average age 26.2 yr) were selected as subjects. Nutrient intake was investigated by questionnaire and 24-hr recall method. Antropometric assessments of the subjects were investigated by SBIA method (Segmental bioimpedance assay, Inbody 3.0). The results were as follows: mean body weight was 60.7 kg, mean body height 161.7 cm and mean BMI 23.4. Status of energy intakes significantly decreased (p<0.01) and dietary fiber intakes significantly increased (p<0.001) after supplementation. BMI and WHR (waist-hip ratio) significantly decreased (p<0.01) and body fat significantly decreased after supplementation (p<0.001). Total cholesterol and LDL-cholesterol significantly decreased after supplementation (p<0.05). HDL-cholesterol was negatively correlated with BMI and WHR (p<0.01). LDL/HDL ratio was positively correlated with BMI (p<0.01) and WHR (p<0.05). Above results of this study show that low-molecule peptide, green tea leaves and dietary fiber supplementation-added routine diet improves lessening body fat distribution, total cholesterol, LDL-cholesterol. Especially, decrease of abdominal fat and WHR were notable. That meant decrease of risk factors.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.17 no.3
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• pp.92-95
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• 2017

Fabry disease (FD) is an X-linked lysosomal storage disorder caused by an ${\alpha}$-galactosidase A (GLA, MIM 300644) enzyme deficiency due to pathogenic variants in the ${\alpha}$-galactosidase A gene (GLA). The disease leads to accumulation of globotriaosylceramide (Gb3) and related glycophospholipids affecting nearly all major organ systems, with the primary sites damaged by Gb3 including renal glomeruli, myocardium, neurons of the dorsal ganglion and autonomic nervous system, and vascular endothelial and smooth muscle. Progressive deposition in these organ systems present with various clinical manifestations including acroparesthesia, renal failure and heart failure. Here, we report a Chinese male diagnosed with Fabry disease in his late $4^{th}$ decades showing improvement of acroparesthesia during enzyme replacement therapy (ERT). A 48-year-old Chinese man who presented with chronic recurrent severe burning pain in his fingers and toes since the age of 10, with worse involvement of the former visited to our clinic for further evaluation. His medical history included a transient ischemic attack aged 40 and diagnosed with stage 4-5 chronic kidney disease aged 47. In the family history, the patient's brother was found to be have Fabry disease 1 month before his visit. Except for his brother, all other members of the family are healthy. Based on his medical history and family history, he was strongly suspicious for Fabry disease. He was found to have a galactose-alpha-1,3-galactose level 4.96 (Reference range, 42.5-67.9) suggestive of Fabry disease. The followed sequencing of GLA coding region in our patient revealed hemizyosity for the mutation c.988C>T (Q330X) in Exon 7. Since ERT start, he showed significant improvement in his symptoms of burning sensation of fingers and toes. On the contrary, due to deteriorating kidney function even with ERT, he is considered for kidney transplantation. Despite of diagnostic delay until late 4th decades, ERT showed a potential improvement of acroparesthesia in our patient. However, late start of ERT can lead to poor outcome in multiorgan function. Therefore, early diagnosis with high index of suspicion followed by continuous ERT with regular monitoring have an impact on quality of life in Fabry disease.

• Childhood Kidney Diseases
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• v.1 no.2
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• pp.170-175
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• 1997

Purpose : Hemolytic uremic syndrome(HUS), known as a most common cause of childhood renal failure in western countries, has been a relatively rare disease in Korea. Although the reported cases were not related to any specific cause in Korea, there was an outbreak of HUS with bloody diarrhea in Japan last year. We report here that we experienced the several typical HUS last year. Patients : From Jan.1996 to Dec. 1996, five patients were diagnosed as HUS at Samsung Seoul Medical Center, Dept. Pediatrics. Results : 1) The age of onset was below 3 years in 3 cases and above 9 years in 2 cases. 2) All the cases happened between summer and autumn. Three patients had domestic travel and 4 patients drank well or spring water before the symptoms. 3) The clinical manifestation was generalized edema, oliguria, anuria and hematuria. The bloody diarrhea were present in 5 cases and 1 patient had operation with the impression of appendicitis. 4) There was no bacteria which was isolated from the blood or stool samples. 5) Renal biopsies were performed in 2 cases, because of protracted clinical course. One showed microthrombotic angiopathy and the other cortical necrosis with necrotizing glomeruli. 6) Complete recovery was the outcome in 4 cases and one case progressed to chronic renal failure. Conclusion : In conclusion, typical HUS associated with bloody diarrhea, epidemic and good prognosis can be found in Korea and careful surveillance of the pre-clinical cases will be necessary.