• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.1278-1289
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• 2008

Currently in increasing number of urban tunnels with small overburden are excavated according to the principle of the New Austrian Tunneling Method (NATM). Successful design, construction and maintenance of NATM tunnel in urban area demands prediction, control and monitoring of surface settlement, gradient and ground displacement with high accuracy. Use of measured displacement for parameter determination has been researched over the years, and one geotechnical engineering principle has been formed as back analysis. In this paper, back analysis of a ground deformational behavior involving nonlinear behavior is discussed. It is of primary importance to make reliable prediction of deformational behavior for shallow tunnels in soft ground. However, predictions made often prove to be incorrect due to complexity of constitutive law and other relevant factors. Back analysis therefore becomes more important, for it may be used to interpret measured displacement to derive nonlinear material characteristics. The paper shows some example in which a deformational mechanism is studied in the light of inhomogeneous distrubution of Young's module, from which a logic is derived to identify two different types of nonlinear constitutive relationships.

• 대한임베디드공학회논문지
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• 제15권5호
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• pp.227-234
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• 2020

In this paper, we propose wav-U-Net to improve speech enhancement in heavy noisy environments, and it has implemented three principal techniques. First, as input data, we use 128 modified Mel-scale filter banks which can reduce computational burden instead of 512 frequency bins. Mel-scale aims to mimic the non-linear human ear perception of sound by being more discriminative at lower frequencies and less discriminative at higher frequencies. Therefore, Mel-scale is the suitable feature considering both performance and computing power because our proposed network focuses on speech signals. Second, we add a simple ResNet as pre-processing that helps our proposed network make estimated speech signals clear and suppress high-frequency noises. Finally, the proposed U-Net model shows significant performance regardless of the kinds of noise. Especially, despite using a single channel, we confirmed that it can well deal with non-stationary noises whose frequency properties are dynamically changed, and it is possible to estimate speech signals from noisy speech signals even in extremely noisy environments where noises are much lauder than speech (less than SNR 0dB). The performance on our proposed wav-U-Net was improved by about 200% on SDR and 460% on NSDR compared to the conventional Jansson's wav-U-Net. Also, it was confirmed that the processing time of out wav-U-Net with 128 modified Mel-scale filter banks was about 2.7 times faster than the common wav-U-Net with 512 frequency bins as input values.

• 한국인구학
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• 제12권2호
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• pp.45-55
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• 1989

In recent years the life expectancy of the Korean people has been increasing appreciably because of the improvement in living conditions and public health facilities as well. However, there exist considerable constraints in the measurement of Korea's mortality rate. In elaboration, there are quite a few persons who do not submit birth and death reports, thereby lowering the reliability of statistical data. The 1978-1979 life table of the Korean people is still considered the latest one. Nevertheless, a decade has passed since its publication, and the need for a better life table reflecting realities is inc-reasingly growing. Capitalizing on the annual report of demographic statistics and demographic sample survey data m 1988, I have worked out the 1986 tentative life table of the Korean people and found out the following : 1. The male life expectancy in the 1978-1979 life table of the Korean people is 62.7 years old, and that of the female sex is 69.1 years old whereas the average life expectancy of the male sex in the 1986 life table stands at 66.3 years old, and that of the female sex is 74.5 years old. The average life expectancy is up by 3.5 years old for the male sex and also, up 5.4 years old for the female sex, res-pe ctively. 2. A gap between the male and female life expectancies in the 1978-1979 life table was 6.4 years old, while that of the 1986 life table was 8.2 years old. It means the female life expectancy has increased substantially. 3. The infant mortality rate has decreased, compared with the 1978-1979 level, yet it is still above those of Japan and Taiwan. 4. The mortality rate of the middle - aged men in the forties remains high, as was the case in the 1978-1979 period.

• 한국작물학회지
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• 제35권2호
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• pp.171-175
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• 1990

1. Polyacrylamide gel electrophoresis를 이용하여 국내외 재래종과 야생종 대두 계통들의 trypsin inhibitor의 변이를 규명하기 위하여 본 시험이 시도되었으며 1706계통의 한국산 재래종과 103계통의 한국 야생종콩, 그리고 167계통의 외래 재배종과 71계통의 외국 야생종 대두가 공시되었다. 2. Trypsin inhibitor를 함유하지 않은 ti/ti형과 Ti c/c형은 한국 재래종에서만 발견되었으며, Ti$^{*}$ c형을 Hymowitz도 일본 대두품종에서 보고한 바 있으나 그도 이 계통은 한국 도래종일 가능성이 크다고 보고 한 바 있다. 3. 한국기원의 콩에서 trypsin inhibitor에 관한 이형접합형의 출현빈도가 외국 기원 콩 계통에서 보다 비교적 높았으며, 재래종에서 3.6%(N=61)와 야생종에서 9.7%(N=10)이었으며 종합적으로 보아 중국, 일본 등의 대두에 비해 한국 기원의 콩이 가장 큰 변이를 나타내고 있음을 확인하였다.

• Journal of Microbiology and Biotechnology
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• 제17권9호
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• pp.1504-1512
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• 2007

The fpr gene, which encodes a ferredoxin-$NADP^+$ reductase, is known to participate in the reversible redox reactions between $NADP^+$/NADPH and electron carriers, such as ferredoxin or flavodoxin. The role of Fpr and its regulatory protein, FinR, in Pseudomonas putida KT2440 on the oxidative and osmotic stress responses has already been characterized [Lee at al. (2006). Biochem. Biophys. Res. Commun. 339, 1246-1254]. In the genome of P. putida KT2440, another Fpr homolog (FprB) has a 35.3% amino acid identity with Fpr. The fprB gene was cloned and expressed in Escherichia coli. The diaphorase activity assay was conducted using purified FprB to identify the function of FprB. In contrast to the fpr gene, the induction of fprB was not affected by oxidative stress agents, such as paraquat, menadione, $H_2O_2$, and t-butyl hydroperoxide. However, a higher level of fprB induction was observed under osmotic stress. Targeted disruption of fprB by homologous recombination resulted in a growth defect under high osmotic conditions. Recovery of oxidatively damaged aconitase activity was faster for the fprB mutant than for the fpr mutant, yet still slower than that for the wild type. Therefore, these data suggest that the catalytic function of FprB may have evolved to augment the function of Fpr in P. putida KT2440.

• 한국임상수의학회지
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• 제11권2호
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• pp.507-516
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• 1994

The purposes of this investigations were survey of the occurred bacterial diseases, development of new animal health drug, guidance to formers on the treatment and control methods of diseases. Some series of investigations have been carried out by microbiological, pathological and serological examinations. The results could be summarized as follows. 1. A total of 953 cases of outbreaked swine diseases have been diagnosed in Clinical pathology laboratories, Bayer Vet Res Institute during 8 years (from 1986 to 1993). The high incidence diseases were colibacillosis, pleuropneumonia, streptococcal infection and pasteurellosis in decreasing order. 2. Pleuropneumonia caused by Actinobacillus pleuropneumoniae was the most important respiratory diseases and pasteurellosis by Pasteurella multocide could be confirmed in several cases. 3. Actinobacillus pleuropneumoniae 50 strains were isolated and identified by biochemical and serological tests. In serotyping test, 22 isolated strains were serotype 5, 21 strains as serotype 2, each 2 strains as serotype 3 and 7 by the coagglutination test. 4. Colibacillosis and edema discase caused by Escherichia coli has been the most predominant outbreaked disease in this investigations. The 100 isolates of E coli strains were sensitive to amikacin, colistin, enrofloxacin, gentamycin and trimethoprim -sulfamethoxazole. 5. Swine erysipelas caused by Erysipelothrix rhusiopathiae was confirmed 25 cases as acute septicemic forms. Isolates of E rhusiopathiae were highly sensitive to ampicillin, cephalothin, enrofloxcin, penicillin and tetracycline. 6. The 49 cases of hemorrhagic and necrotic enteritis in piglets were observed and 13 strains of Clostridium perfringens could be isolated and confirmed by biological and serological test. Isolates of Clostridium perfringens type C were highly sensitive to ampicillin, cephalothin, enrofloxacin, penicillin and trimethoprim- sulfamethoxazole. 7. The 14 strains of Streptococcus suis type II could be isolated from meningitis of piplets. 8. Polyserositis caused by Haemophilus parasuis and salmonellosis were observed and confirmed. Also Corynebacterial infections and several parasitosis have been also observed in this investigations.

• 열처리공학회지
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• 제6권1호
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• pp.17-25
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• 1993

The Cu - $Nb_3Sn$ composites wire as a superconducting material was prepared by in situ method as follow: Cu - 15wt.% Nb alloys which were melted in a high -frequency induction furnace and casted in bar were cold-worked up to the final diameter of 0.24 mm, electroplated with Sn, pre-treated in two steps and then diffused at $550{\sim}650^{\circ}C$ for 24 ~ 96 hrs. The overall $J_c$ and $T_c$ of the specimens were measured by the four point-probe method at 10 K in the magnetic field of 0 Tesla. The overall $J_c$ of the composites wire which diffused at $550^{\circ}C$ after pre-treating in two steps were generally higher than those of the wire at either $600^{\circ}C$ or $650^{\circ}C$. For the specimens diffused at $550^{\circ}C$, the overall $J_c$ were increased until 72 hrs. of diffusion time and then decreased. However, in case of diffusion at $600^{\circ}C$ and $650^{\circ}C$, the overall $J_c$ were gradually decreased from the beginning. The maximum overall $J_c$ obtained in this experiment was $1.3{\times}10^4\;A/cm^2$, which was measured for the specimen diffused at $550^{\circ}C$ for 72 hrs. When the specimens were diffused at $550^{\circ}C$ for 72 hrs, after pre-treating, the measured critical temperature, $T_c$ was 16.19 K. Similar $T_c$ value were obtained in other specimens regardless of diffusion time and temperature.

• Applied Biological Chemistry
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• 제43권2호
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• pp.110-115
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• 2000

마늘 추출물의 아질산염 소거능과 항산화 효과 및 nitrosamine 생성 억제 작용에 대해 조사한 결과는 다음과 같다. 아질산염 소거작용은 마늘의 물 추출물과 에탄올 추출물에서 모두 pH가 낮을수록 높게 나타났고, pH가 높을수록 소거작용이 떨어졌으며, 특히 에탄올 추출물 첨가시 pH 1.2에서 89.6%의 뛰어난 소거효과를 나타냈다. 이들 마늘 추출물은 전자공여작용에도 높은 호과를 나타내었는데, 에탄올 추출물이 물 추출물 보다 높았으며, linoleic acid의 항산화 효과도 에탄을 추출물이 우수한 것으로 나타났다. Nitrosation 반응에서는 에탄올 추출물 첨가시 pH 1.2 및 3.0에서 80% 이상, 그리고 pH 6에서는 29.9%의 억제 효과가 있는 것으로 나타나 반응 pH에 따라 억제효과의 차이가 컸다.

• 지질공학
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• 제16권3호
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• pp.275-282
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• 2006

본 연구는 모형실험장치를 이용하여 인공강우에 의한 산사태 발생특성과 사태물질의 확산거동특성을 파악하기 위하여 수행되었다. 본 연구에서는 강우강도와 사면경사의 변화에 따른 다양한 실험조건하에서 일정 시간 간격으로 간극수압, 사면붕괴양상 및 변위, 그리고 토사의 확산면적 등을 각각 측정하였다. 실험 중 복수의 비디오 카메라와 디지털 스틸카메라로 촬영한 후, 이미지 분석을 실시하여 시간대별 산사태 발생양상 및 사태물질 확산특성 자료를 취득하였다. 실험결과에 따르면, 간극수압은 강우강도 및 사면경사에 비례하여 변화하며 이에 따라 강우강도 및 사면경사가 커짐에 따라 산사태가 발생할 가능성도 증가하였다. 사태물질의 확산면적은 강우강도, 강우지속시간, 그리고 사면경사의 증가에 비례하는 양상을 가짐을 확인하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.955-958
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• 2003

Nepal is a country of mountains The higher order geodetic points were mostly established on the top of mountains and these points were used for the geodetic network extension. Lower order geodetic control networks were established at different times and used for the surveying and mapping activities of the country.. It has been found that the rate of convergence between north and south borders of Nepal to be 21${\pm}$2 mm each year and the rate translation of Kathmandu to 55${\pm}$3 mm/year to the plates. The most intense deformation in Nepal occurs along the belt of high mountains along its northern border res ulting in a strain contraction rate normal to the Himalayan Arc. This belt is approximately 40 km wide and extends into southern Tibet.( 13). Recently Survey Department of Nepal has lunched a program of strengthening the existing geodetic network of Nepal and re-observed the position of higher order geodetic points by using geodetic GPS receivers to evaluate their position and thus to define the precision of the control points once again. This paper describes the observation procedure and the adjustment results of the existing higher order control network of Nepal established in different time using different types of equipment and techniques; and highlights the observation procedure and the result obtained after the post processing of the GPS observation results. Attempt has been made to give the procedure and identify the methodology for the re observation of existing higher order geodetic points by using GPS receiver and post processing the observed data so that the existing higher order geodetic points are within the given accuracy standard.