• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 추계학술발표회
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• pp.231-234
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• 2001

When constructing subsurface structures and/or wells, the precise estimates of hydraulic parameters must be obtained for operating safety and/or for developing necessary quantity of groundwater. Hydraulic conductivity is mainly subjected to the characteristics of fracture network in the fractured media such as fracture orientation and angle, fracture aperture and frequency, fracture length, interconnectivity of fractures, and filling material, feature of fracture plane. In this study we conducted water injection test at afferent depths on six boreholes drilled in granite of Mt. Geumjeong. hydraulic conductivity was calculated using Moye and Hvorslev methods. The relation between hydraulic conductivity and fracture frequency data obtained from acoustic televiewer and core log were analyzed. The result shows that the correlation between the hydraulic conductivity and the fracture frequency data obtained from acoustic televiewer is better than that with the core log.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.69-72
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• 1999

In this paper, an efficient time domain equalization algorithm for discrete wavelet multitone(DWMT) data transmission is developed. In this algorithm, the time domain equalizer(TEQ) consists of two stages, i.e., the channel impulse response shortening equalizer(TEQ-S) in the first stage and the channel frequency flattening equalizer(TEQ-F) in the second stage. TEQ-S reduces the length of transmission channel impulse response to decrease intersymbol interference(ISI) followed by TEQ-F that enhances the channel frequency response characteristics to the level of an ideal channel, hence diminishes the bit error rate. TEQ-S is implemented using the least-squares(LS) method, while TEQ-F is designed by using the least mean-square(LMS) algorithm. Since DWMT system also requires of the frequency domain equalizer in order to further reduce ICI and ISI the hardware complexity is an another concern. However, by adopting an well designed and trained TEQ, the hardware complexity of the whole DWMT system can be greatly reduced.

• 패션비즈니스
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• 제11권4호
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• pp.82-91
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• 2007

The purpose of this study is to evaluate the differences of visual effects by variations in the shoulder length and puff volume of the puff sleeve blouse. The stimuli are 21 samples: 3 variations of the shoulder length and 7 variations of the puff volume. The data has been obtained from 40 fashion design majors. The data has analyzed by Frequency, Factor Analysis, ANOVA, Scheffe's test and MCA method. The result of the study are as follows. The visual effects by the shoulder length and puff volume are composed of 4 factors : the width of the upper body, the shape of the breast part, the shape of the neck part and the shape of the upper arm. In these factors, the width of the upper body is estimated by most important factor. In view of the visual effects by variation of the shoulder length, the shorter shoulder length goes, the more positive visual image comes in the shape of the breast part. In comparison of the differences of visual effects by the 7 variations of puff volume, the arm looks thin and long when the puff volume goes enough and the breast part has a better visual assesment in case the puff volume goes poor. In the interaction effects between the shoulder length and puff volume, the shoulder length have significant differences in the shape of the breast part, the shape of the neck part and the shape of the upper arm and puff volume has significant difference in the width of the upper body.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 춘계학술대회 논문집
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• pp.81-88
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• 2000

Unlike structures in the air, the vibration analysis of a submerged or floating structure such as offshore structures or ships is possible only when the fluid-structure interaction is understood, as the whole or part of the structure is in contact with water. Specially, the importance of the added mass is not necessary to say like the submerged vehicle, all of the hull body, is positioned in the water. This paper introduce two method to find natural frequency in consideration of fluid-structure modal coupled vibration analysis. The purpose of this study is to analyze of the vibration characteristic of submerged vehicle to obtain the anti-vibration design data, which could be used in the preliminary design stage data. Underwater pressure hull of submerged vehicle is used as the model of this study. The F.E.M model is meshed by shell and beam element. Also, considering of the inner hull weight, mass element is distributed in the direction of hull length. Numerical calculations are accomplished using the commercial B.E.M code. The characteristics of natural frequency(eigenvalues), mode shape(eigenvectors) and frequency-displacement response are analyzed. The results of this study will be used as the useful design data in preliminary anti-vibration design stage.

• 대한원격탐사학회지
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• 제27권3호
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• pp.225-234
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• 2011

This study proposes an inversion algorithm to extract the surface parameters, such as surface roughness and soil moisture contents, using multi-frequency SAR data. The study areas include the tidal flats of Jebu Island and the reclaimed lands of Hwaong district on the western coasts of the Korean peninsula. SAR data of three frequencies were accordingly calibrated to provide precise backscattering coefficients through absolute radiometric calibration. The root mean square (RMS) height and the correlation length, which can describe the surface roughness, were extracted from the backscattering coefficients using the inversion of the Integral Equation Method (IEM). The IEM model was appropriately modified to accommodate the environmental conditions of tidal flats. Volumetric soil moisture was also simultaneously extracted from the dielectric constant using the empirical model, which define the relations between volumetric soil moistures and dielectric constants. The results obtained from the proposed algorithm were verified with the in-situ measurements, and we confirmed that multi-frequency SAR observations combined with the surface scattering model for tidal flats can be used to quantitatively retrieve the geophysical surface parameters in tidal flats.

• The Journal of Advanced Prosthodontics
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• 제3권4호
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• pp.190-195
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• 2011

PURPOSE. This study evaluated the initial stability of different implants placed above the bone level in different types of bone. MATERIALS AND METHODS. As described by Lekholm and Zarb, cortical layers of bovine bone specimens were trimmed to a thickness of 2 mm, 1 mm or totally removed to reproduce bone types II, III, and IV respectively. Three Implant system (Br${\aa}$nemark System$^{(R)}$ Mk III TiUnite$^{TM}$, Straumann Standard Implant SLA$^{(R)}$, and Astra Tech Microthread$^{TM}$-OsseoSpeed$^{TM}$) were tested. Control group implants were placed in level with the bone, while test group implants were placed 1, 2, 3, and 4 mm above the bone level. Initial stability was evaluated by resonance frequency analysis. Data was statistically analyzed by one-way analysis of variance in confidence level of 95%. The effective implant length and the Implant Stability Quotient (ISQ) were compared using simple linear regression analysis. RESULTS. In the control group, there was a significant difference in the ISQ values of the 3 implants in bone types III and IV (P<.05). The ISQ values of each implant decreased with increased effective implant length in all types of bone. In type II bone, the decrease in ISQ value per 1-mm increase in effective implant length of the Br${\aa}$nemark and Astra implants was less than that of the Straumann implant. In bone types III and IV, this value in the Astra implant was less than that in the other 2 implants. CONCLUSION. The initial stability was much affected by the implant design in bone types III, IV and the implant design such as the short pitch interval was beneficial to the initial stability of implants placed above the bone level.

• 한국정보통신학회논문지
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• 제7권7호
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• pp.1575-1581
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• 2003

사회가 고도의 디지털 정보화 시대로 급속히 발전함에 따라 영상 및 음성 데이터의 획득, 전송, 저장을 위한 멀티 미디어 통신 서비스가 상용화 되어가고 있다. 그러나, 여전히 데이터를 디지털화하거나 전송하는 과정에서 여러 가지 원인에 의해 노이즈가 발생하고 있으며, 이러한 노이즈를 제거하기 위한 연구는 지금까지 계속되고 있다. 노이즈를 제거하기 위해 기존에 FFT와 STFT 등이 있었으나, 신호에 대한 시간정보를 알 수 없고 시간-주파수 국부성이 상충관계를 갖는다. 따라서, 이러한 한계를 극복하기 위해 신호처리 분야의 새로운 기법으로 제시된 웨이브렛 변환은 시간-주파수 국부성을 가지므로, 다양한 신호를 해석하는데 용이할 뿐만 아니라, 다중 해상도 해석이 가능하므로 최근 여러 분야에 응용되고 있다. 그리고, 두 개의 웨이브렛 기저가 힐버트 변환쌍을 형성하도록 설계될 때, 웨이브렛 쌍은 데이터 특징 검출에서 기존의 DWT보다 우수한 성능을 갖는다. 따라서, 본 연구에서는 절단된 계수 벡터에 의해 설계된 두 개의 dyadic 웨이브렛 기저와 적응-길이 메디안 필터를 사용하여 임펄스 노이즈를 제거하였다.

• 대한전자공학회논문지SD
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• 제49권1호
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• pp.25-34
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• 2012

본 논문은 고속 WPAN 시스템에 대한 가변 길이 8-병렬 리드-솔로몬(RS) 복호기에 관한 일반적인 구조를 제안한다. 제안된 구조는 RS(255,239) 코드뿐만 아니라 다양한 단축화 RS 부호들을 지원 할 수 있다. 특히, 가변길이 구조는 다양한 단축화 RS 부호에 대해 가변적인 낮은 지연을 제공하며, 8-병렬 구조를 적용하여 높은 데이터 처리율을 제공한다. 제안된 RS 복호기는 90-$nm$ CMOS 표준 셀 기술을 사용하여 성능 분석을 수행하였고, 클록 주파수 300$MHz$에서 19-$Gbps$ 데이터 처리율을 제공한다.

• 한국농공학회논문집
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• 제57권5호
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• pp.89-99
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• 2015

In this research, 1,032 data of precise safety inspection from 2004 to 2013 are gathered and constructed for finding effective safety inspection systems. Items are extracted from constructed data and factors for typology are decided with statistical method such as principle component analysis and cluster analysis. For factor decision, we extruded independent characteristics such as morphological and geographical characteristic, and deleted items which can be expressed by combination of independent characteristics. Four factors such as total storage, watershed ratio, levee length ratio, and spillway length ratio are extracted in this process. In cluster analysis, levee length ratio is excluded because it is not separated as cluster. Finally nine types of agricultural reservoir are extruded by total storage, watershed ratio, and spillway length ratio with frequency analysis.

• Asian-Australasian Journal of Animal Sciences
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• 제25권11호
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• pp.1515-1520
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• 2012

Insulin-like growth factor binding protein-3 (IGFBP-3) gene is important for regulation of growth and development in mammals. The present investigation was carried out to study DNA polymorphism by PCR-RFLP of IGFBP-3 gene and its effect on fibre traits of Chinese Inner Mongolian cashmere goats. The fibre traits data investigated were cashmere fibre diameter, combed cashmere weight, cashmere fibre length and guard hair length. Four hundred and forty-four animals were used to detect polymorphisms in the hircine IGFBP-3 gene. A 316-bp fragment of the IGFBP-3 gene in exon 2 was amplified and digested with HaeIII restriction enzyme. Three patterns of restriction fragments were observed in the populations. The frequency of AA, AB and BB genotypes was 0.58, 0.33 and 0.09 respectively. The allelic frequency of the A and B allele was 0.75 and 0.25 respectively. Nucleotide sequencing revealed a C>G transition in the exon 2 region of the IGFBP-3 gene resulting in R158G change which caused the polymorphism. Least squares analysis revealed a significant effect of genotypes on cashmere weight (p<0.0001), cashmere fibre length (p<0.001) and hair length (p<0.05) of the animals. The effect of genotypes on cashmere fibre diameter was not statistically significant (p>0.05). The animals of AB and BB genotypes showed higher cashmere weight, cashmere fibre length and hair length than the animals possessing AA genotype. These results suggested that polymorphisms in the hircine IGFBP-3 gene might be a potential molecular marker for cashmere weight in cashmere goats.