• Journal of Korea Society of Industrial Information Systems
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• v.11 no.3
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• pp.15-19
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• 2006

In shallow water active sonar environment, reverberation which is a non-white noise is one of the main source of performance degradation of target detection. In this case, the received signal is whitened before applying matched filter known as an optimum filter in the presence of white noise. However implementation of this method is very difficult because of the non-stationary characteristic of reverberation. Traditionally reverberation is assumed local stationary. In this paper, we estimate a range of stationary of reverberation signal, and then propose a pre-whitening method which improve the performance of pre-whitening block normalized matched filter in presence of non-white reverberation noise. Proposed whitener shows better whitening performance than traditional whitener because it use later as well as before reverberation of target signal. To evaluate performance of the proposed whitener, an actual measurement data sampled at the East-Sea is used for computer simulation. The target detector with new whitener is shown better performance than detector with traditional whitener.

• Journal of Convergence for Information Technology
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• v.11 no.5
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• pp.23-29
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• 2021

Recently, a situation in which a specific content service is impossible worldwide has occurred due to a failure of the platform service and a significant social and economic problem has been caused in the global service market. In order to secure the stability of platform services, intelligent platform operation management is required. In this study, big data flow management(BDFM) and implementation method were proposed to quickly detect to abnormal service status in the platform operation environment. As a result of analyzing, BDFM technique improved the characteristics of abnormal failure detection by more than 30% compared to the traditional NMS. The big data flow management method has the advantage of being able to quickly detect platform system failures and abnormal service conditions, and it is expected that when connected with AI-based technology, platform management is performed intelligently and the ability to prevent and preserve failures can be greatly improved.

• Clinical and Experimental Pediatrics
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• v.46 no.7
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• pp.687-694
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• 2003

Purpose : Regeneration and repair after ischemic renal injury appears to be modulated by circulating or locally produced growth factors. This study examined the changes of serum insulin like growth factor(IGF-I) and renal expression of IGF-I and II, vascular endothelial growth factor(VEGF), transforming growth $factor-{\beta}$($TGF-{\beta}$), and connective tissue growth factor(CTGF) during the active regeneration period after acute ischemic injury. Methods : Sera and kidney tissue samples(whole kidney, cortex, outer medullae and inner medullae) were obtained before and after one, three, five and seven days of 40 minutes bilateral renal pedicle clamping. Acute renal failure was assessed by measuring the concentration of serum creatinine. Serum IGF-I level was measured by radioimmunoassay. The mRNA expression in kidney was measured by RT-PCR. The distribution of IGF-I and CTGF was detected by immunohistochemistry. Resuts : Serum IGF-I concentration after one day following acute ischemic renal injury was significantly decreased compared to preischemic value. The mRNA levels of IGF-I, IGF-II, $TGF-{\beta}1$ and VEGF in whole kidney were temporally decreased on day one of ischemic injury. IGF-I and IGF-II expressions in outer medullae were significantly decreased on day one after ischemic injury. $TGF-{\beta}1$, CTGF and VEGF expressions were markedly decreased in medullae after one day of ischemic injury compared to other kidney sections. IGF-I was markedly decreased in cortical tubules on day one of uremic rat. CTGF was markedly increased on tubule within three days of ischemic injury. Conclusion : These findings suggest that IGFs, $TGF-{\beta}1$ and CTGF may involve in the pathogenesis or the recovery from acute ischemic renal injury.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.9
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• pp.1179-1186
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• 2009

This study was carried out to investigate the effect of saengmaec-san on the level of blood glucose and serum components in streptozocin (STZ)-induced diabetic rats. The experimental groups were divided into normal group (normal), diabetic control group (Dia-control), 10% saengmaec-san (white ginseng) group (DA), 10% saengmaec-san (fermented white ginseng) group (DB), 10% saengmaec-san (fermented red ginseng) group (DC), 5% saengmaec-san (extruded and fermented white ginseng) group (DDL), 10% saengmaec-san (extruded and fermented white ginseng) group (DDH). The body weight after induction of diabetes was 85.4% in the Dia-control group compared with the normal group. But in the DA group, the body weight showed clear sign of recovery almost normal level after administration of saengmaec-san for two weeks. The food efficiency ratios (FER) were 5.94% in the normal group. But it was significantly decreased in the Dia-control group (0.58%). All the treatment groups showed increase of FER compared with the Dia-control group. The level of blood glucose was significantly increased in the STZ-induced diabetes groups but it was decreased in all the treatment groups after administration for 2 weeks. Serum creatinine level were significantly higher in the STZ-induced diabetes groups and after administration of saengmaeg-san for 2 weeks while the level of serum creatinine was decreased 33.3% in the DB group. After administration of saengmaec-san for two weeks, serum total cholesterol level were significantly lower in all treatment groups than the first day of the total cholesterol level. The level of serum triglyceride was increased in all the treatment groups compared with the first day of triglyceride level. The level of serum HDL-cholesterol, after STZ-induced diabetes, was decreased in all treatment groups but particularly in the DDL and DDH groups increased HDL-cholesterol level compared with the first day of the saengmaec-san administration. Compared with the beginning of experiment, Atherogenic index (AI) were significantly decreased in all treatment groups than the Dia-control group and showed clear sign of recovery almost normal level. These results suggested that the saengmaec-san could be developed as an antidiabetic agent.

• Childhood Kidney Diseases
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• v.8 no.1
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• pp.18-25
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• 2004

Purpose : Alport syndrome is clinically characterized by hereditary progressive nephritis causing ESRD with irregular thickening of the GBM and sensory neural hearing loss. The mutations of type IV collagen gene(COL4A5) located on the long arm of X chromosome is considered responsible for most of the structural abnormalities in the GBM of Alport patients. Since no definite clinical prognostic predictor has been reported in the disease yet, we designed this study to evaluate the significance of genetic polymorphism of the angiotensin converting enzyme in children with Alport syndrome as a prognostic factor for disease progression. Methods : ACE I/D genotype were examined by PCR amplification of the genomic DNA in 12 patients with Alport syndrome and 12 of their family members. Alport patients were divided into two groups; the conservative group, those who had preserved renal function for more than 10 years of age, the early CRF group, those who had progressed to CRF within 10 years of age. Results : The mean age of onset was $3.45{\pm}2.4$ years in the conservative group, $4.4{\pm}1.2$ years in the early CRF group. Sex ratios were 5:3 and 2:1 in each group. Among 12 cases of patients, 4 cases were in early CRF group and their mean duration of onset to CRF was 4.5 yews(8.9 years of age). Eight patients(67%) were in the conservative group and they had normal renal function for more than 10 years of age(mean duration of renal preservation was 10.6 years). The incidence of II type ACE gene were in 25.0%(3 cases), ID type in 41.7%(5 cases), DD type in 33.3%(4 cases). There was no significant difference between Alport patient and normal control(II type 44.3%, ID type 40.9%, DD type 14.8%). The incidence of DD type of early CRF group were higher than that of the conservative group(75% vs 12.5%)(p<0.05). There was no difference in ACE gene polymorphism between normal Alport family members and control group. Conclusion : Even though there was no significant difference of ACE polymorphism between Alport patients and the normal control group, the incidence of DD type is significantly increased in early CRF group which means DD type of ACE polymorphism has a possibility of being a predictor for early progression to CRF in Alport patients.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.248-261
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• 1999

In order to define a current set of Korean children norm with mixed dentition, following study was done. The subjects were 102 healthy dentition contestants(48boys, 54girls). Standardized lateral head roentgenograms were taken, and Ricketts analysis was done. Results were as follows: 1. Length of anterior cranial base, posterior facial height, corpus length were longer in male than in female(p<0.05), and Porion was located posteriorly in male than in female(p<0.01). 2. Through facial depth, Pogonion of male was more forwardly positioned(p<0.05), mandible was significantly steeper in female, and maxillary anterior teeth were significantly tipped forward in male(p<0.05). 3. Variables such as length of anterior cranial base, upper molar position(p<0.01) and corpus length(p<0.05) were significantly changed by age. 4. Maxillary height, facial depth, mandibular plane angle, convexity were changed by age, but not significantly(p>0.05).

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.4
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• pp.339-346
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• 2010

Purpose: The study was performed to compare the difference of non-invasive tear break-up time (NIBUT) with alignment or steep fitting of soft contact lens in normal and dry eyes. Methods: Total 40 eyes (aged 20~30 years) were classified to the normal (n=20) or dry eye group (n=20) by the diagnosis methods for dry eyes and worn soft contact lens (polymacon material) with alignment or steep fitting. NIBUTs of lens wearers were separately measured at the points of before wearing, immediately after wearing and after stabilization of tear film. Results: With alignment fitting, averaged NIBUT in the dry eye group after stabilization of tear film was not significantly different from that of the normal eye group. However, averaged NIBUTs in the normal and dry eyes had significant difference when measured immediately after lens wearing. However, the number of eyes having NIBUT less than 4.0 second was 30% higher compared to the number of normal eyes with steep fitting when measured immediately after wearing. Some shorten NIBUT in dry eyes with steep fitting was also shown after stabilization of tear film. Conclusions: These results suggest that wearing soft contact lens in dry eyes differently affect tear film compared to normal eyes. Thus, dry eyes need more advertent fitting for contact lens wearing because of unstable tear film.

• Proceedings of the Korea Society of Costume Conference
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• 2003.05a
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• pp.27-27
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• 2003

오늘날의 현대인들은 과거에는 드러낼 수 없었던 잔인하고 파괴적인 인간 본능의 모습들을 과격하게 보여주고 있다. 특히 1990년대 이후 세기말의 시대적 불안과 사회적 혼란을 반영하여 비정상적이며, 과격하며, 혐오스러운 반면 동시에 재미와 웃음이 섞인 그로테스크한 현상은 사회전반에 만연한 심리적 부조화와 소외현상 등 현대 사회의 현안 문제점들을 드러내고 있는 것이다. 복식에서 그로테스크는 오래 전부터 왜곡, 과장, 축소, 변형 등 여러 조작을 통하여 표현되어왔으며, 이러한 복식은 패션(Fashion) 혹은 패드(Fad)로 이어져왔다. 특히 20세기 후반 포스트모던 시대이후 빈번히 나타나며 더욱 더 충격적인 표현을 시도해 왔다.

• Proceedings of the Korean Society of Grassland Science Conference
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• 1999.06a
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• pp.40-64
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• 1999

최근 전 세계적으로 빈번한 홍수, 폭우, 가뭄, 지진 등 기상재해로 인한 돌발적인 식량공황사태가 이어지고 있는 바 식량자급의 중요성은 아무리 강조하여도 지나치지 않을 것이다. 우리나라의 식량자급률은 30% 정도로 부끄러운 수준이며, 매년 1,200만 톤 이상의 엄청난 양의 배합사료를 수입하고 있다. 또한 대가축의 조사료 자급률은 55% 수준으로 너무나 낮으며, 이 중에서도 반 이상을 사료가치가 낮은 볏짚이 차지하고 있어 농후사료 위주의 비정상적인 축산임은 두말 할 나위가 없는 바, 국내 자급 조사료의 안정적 생산기반 구축은 너무나도 당연하고 절실한 실정이다.(중략)

• 한국전산유체공학회:학술대회논문집
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• 2000.10a
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• pp.54-59
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• 2000

A numerical study of axisymmetric rocket main nozzle flow has been accomplished. The CSCM upwind flux difference splitting method with an iterative time marching scheme having second order accuracy in time and space has been used to simulate unsteady flow characteristics in an axisymmetric rocket main nozzle. Though the pressure vary at nozzle inlet with the lapse of time, Mach No. and the density were not changed significontly compared with the temperature. Specific heat ratio $\gamma$=1.134 predicted higher temperature at nozzle throat and exit and nondimensional thrust coefficients at exit than specific heat ratio $\gamma$=1.4 did.