• Asian-Australasian Journal of Animal Sciences
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• 제8권3호
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• pp.281-287
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• 1995

A study was conducted to investigate the effect of different inclusion levels of urea treated whole-crop wheat silage (UWCWS) in grass silage based rations on the performance of growing beef cattle. The winter wheat (variety, Riband) was harvested (in the summer of 1991) at a dry matter proportion of 520 g/kg and treated with feed grade urea at the rate of 37 kg/tonne crop dry matter and preserved in a heavy duty plastic bag using a silo press. The urea treated whole crop wheat silage (UWCWS) was mixed with grass silage to replace 0.00 (S100), 0.33 (S33) and 0.67 (S67) parts of the forage dry matter and fed ad libitum in a cross over design to 18 Simmental X Holstein Friesian growing beef animals. Two energy sources {one high in starch, rolled barley (RB) and one high in digestible fibre, sugar beet pulp (SBP)} were fed to supply sufficient energy for the efficient use of nitrogen by the rumen micro-organisms. The data on DMIF (dry matter intake of forage), TDMI (total dry matter intake), DLWG (daily live weight gain), FCR (feed conversion ratio) were recorded and faecal samples were collected to determine the digestibility coefficients. Results revealed that with the inclusion of UWCW in the animals' diets the DMI of the forage was significantly increased (p < 0.05). The highest DMIF was found in the treatment "S33" ($6.28{\pm}0.25kg$) where 67% of the silage dry matter was replaced with the UWCW and the lowest value for DMIF was observed in the control treatment ($5.03{\pm}0.23kg$). The DLWG did not differ significantly between the treatments. However, treatment "S100" showed a trend towards a superior DLWG. Feed conversion ratio in the control treatment differed significantly from "S67" and "S33". The addition of the UWCW in the animals' diet resulted in the lower FCR There was no effect of type of energy supplement on any aspect of performance either overall or in interaction with grass silage: UWCWS ratio. The regression and correlation coefficients for DMIF (r = 5.22 + 0.0184x*), DLWG (r = $1.04-0.00086x^{NS}$) and FCR (r = 4.78 = 0.022x*) on the inclusion of UWCW in the diet were calculated. The effect of the inclusion of UWCW on the overall digestibility coefficients was significant (p < 0.05). The addition of the UWCWS in the diet decreased the digestibility of the DM, OM, ADF and NFE but effect on the protein digestibility was non significant. The results of present study suggests that a DLWG slightly over 1 kg can be achieved with UWCW during the store period (period in which animal performance targets are low especially during winter) and the prediction of ME was overestimated as the high intake of DM did not reflect in improved animal performance.

• 한국광학회지
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• 제4권2호
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• pp.200-205
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• 1993

LiI$O_3$ 및 BBO 결정에서 Ti:sapphire 레이저에 대한 제2조화파 발생 실험을 실시하였다. LiI$O_3$ 는 5mm, 10mm의 두 종류를 이용하였으며 BBO의 길이는 7mm이었다. 780nm~810nm 영역에서의 LiI$O_3$ 및 BBO 결정에 대한 제2조화파 변환 효율을 측정하였고 이론과 비교하였다. 또, 펌프 출력에 따른 제2조화파의 출력을 측정함으로서 794nm에서의 제2조화파 변환 계수(conversion coefficient)를 구하였으며, 그 값은 LiI$O_3$ 결정에 대해 (1.06${\pm}0.05){\times}10^4W\;^1$(10mm), (5.28${\pm}0.33){\times}10^5\;W^1$(5mm), 이었고 7mm의 BBO에 대해서는(2.96${\pm}0.05){\times}10^5\;W^1$이었다.

• 한국측량학회지
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• 제16권2호
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• pp.149-158
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• 1998

본 연구에서는 GPS에 의한 2차원 실용좌표의 획득면에 중점을 두고 WGS84와 벳셀타원체간의 3차원 좌표변환에 필수요소인 지역지오이드고 모델없이 두 타원체간 투영좌표의 상호 변환모델식을 구성하여 점검점에 적용하고 실용성과와 비교 고찰하므로서 UTM투영좌표에 의한 타원체간 2차원 좌표변환의 산정법을 제시한 것이다. 인천시지역을 시험모델로 관내 11개 삼각점으로부터 상호변환계수를 도출하고 점검점인 15개 지적삼각점에 적용하여 양방향의 변환정밀도를 분석한 결과, 측지좌표의 경우 위도 및 경도성분에서 각각 $\pm0.006$초, $\pm0.013$초, 평면직교좌 표의 경우는 남북 및 동서방향에서 각각 $\pm{17cm}$ 및 $\pm{30.0cm}$의 표준편차로 변환할 수 있었다. 또한, 남한지역을 대상으로 한 광역망, 경인.충남지역의 지역망 및 인천지역의 국소망으로부터 3-매개변환, 7-매개변환 및 UTM좌표간 변환계수를 각각 산출하여 점검점에 적용하고 변환넓이에 따른 변환기법별 변환특성도 고찰하였다.

• 한국음향학회지
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• 제35권2호
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• pp.134-142
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• 2016

본 논문에서는 40 kHz 초음파 신호를 입 주변에 쏘고, 되돌아오는 초음파 신호를 이용해 음성신호를 합성하는 방법을 소개하고 성능을 평가하였다. 발성하고 있는 입주변에 초음파를 방사하게 되면, 입술, 턱, 뺨 등의 움직임으로 인한 변위로 도플러 현상이 발생하고, 이에 따라 반사 신호에는 본래의 주파수 성분과는 다른 도플러 주파수가 관찰되는데, 본 논문에서는 이러한 도플러 주파수를 이용하여 음성 파라메터를 추정하도록 하였다. 음성합성에 앞서서 초음파 도플러 신호와 음성 신호 간의 상관관계를 각 주파수 별로 분석하였으며, 이로부터 초음파 도플러 신호를 이용한 음성 신호의 합성 가능성을 살펴보았다. 변환에는 초음파 도플러의 정적, 동적 특성을 함께 반영한 특징 변수를 사용하였으며 결합-혼합 가우시안 기법을 이용하여 음성 파라메터로 변환하였다. 5명의 피 실험자를 이용한 음성 합성 실험에서 필터뱅크 에너지 값을 초음파신호의 특징변수로, LPC(Linear Predictive Coefficient) 켑스트럼 계수를 음성 변수로 사용하는 경우 가장 우수한 변환 성능을 나타내었다. 음성신호에서 추출한 여기신호를 이용하여 합성음을 생성하고, 이를 청취하였을 때 72.2 %의 평균 인식율이 얻어짐을 확인할 수 있었다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.235-240
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• 2004

This paper deals with the performance analysis of impulse turbine for owe type wave energy conversion device. Numerical analysis was performed using a commercially-available software FLUENT. This parametric study includes the variation of the setting angle of guide vane. Since parametric study at various flaw coefficients requires tremendous amounts of computing time, two-dimensional cascade flaw approximation was employed to find out optimum principal particulars in rather simple manner. Full three-dimensional calculation was also performed for several cases to confirm the validity of two-dimensional approach. Results were compared to other experimental data, for instance Setoguchi et al (2001)'s extensive set of data, and found to be well demonstrating the usefulness of 2-D analysis. Advantages and disadvantages of each method were also evaluated.

• 생물환경조절학회지
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• 제4권2호
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• pp.232-239
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• 1995

This study was carried out to get required torque data needed to design and develop a roll-up ventilation system in a pipe-constructed plastic film green-house. The results obtained from this study are as follows : 1. The required torques of a roll-up ventilation system in greenhouse are the functions of its length. The torques should multiplied by the conversion coefficients (2.0 in ceiling vent, 1.8 in side vent) in case of application. 2. In constructing pipe-constructed plastic film greenhouse, a shaft pipe is the largest essential element in roll - up shaft weight constitution which have an effect on the required torques. Therefore, the pipe should be light using nonferrous materials like aluminum alloy. 3. A planetary reduction ventilator of differential ring gear type is suitable for a roll-up ventilation system, because it can make high efficient reduction just using the first step shift.

• 한국해양공학회지
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• 제25권1호
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• pp.8-13
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• 2011

A compact array system of small buoys is used for wave energy extraction. To evaluate the performance of this system, hydrodynamic analysis is carried out in regular waves using the higher order boundary element method. The motion response of each buoy is calculated considering hydrodynamic interactions caused by other buoys. The effect of energy extraction device is modeled as a linear damping load. The efficiencies of energy conversion are compared using the various sizes and arrangements of the array system and the damping coefficients for energy extraction. The increase in size or the packing ratio of the system gives better efficiency. However, the wave condition and the cost for the system should be considered to optimize performance from the perspective of engineering and economics. The proposed nondimensionalized damping coefficient for energy extraction is 0.1~0.5.

• 한국정밀공학회지
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• 제23권6호
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• pp.128-135
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• 2006

Rational dynamic modeling and analysis method f3r complex structures are studied with special attention to slide way joints. For modeling of slide way joints, a general modeling technique is used by using the influence coefficients method which is applied to the conversion of detailed finite element model to the equivalent reduced joint model. The theoretical part of this method is illustrated and the method is applied to the structure with slide way joint. In this method, the non-linearity of the contact surfaces is considered within a proper range and the boundary effect of the joint model could be eliminated. The proposed method was applied to finite element modal analysis of a clamp jointed cantilever beam and slide way joints of the vertical type lathe. The method can also be used to other kinds of joint modeling. The results of these analysis were compared with those of Yoshimura models and rigid joint models, which demonstrated the practical applicability of the proposed method.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.119.1-119.1
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• 2011

Since Gratzel et al. reported the first efficient dye-sensitized solar cells(DSSCs) in 1991, they have attracted much attention due to their relatively high power conversion efficiency and potentially low cost production. To date, high performance and good stability of DSSC based on Ru-dyes as a photosensitizer had been widely addressed in the literatures. However, the Ru-dyes are facing the problem of manufacturing costs and environmental issues. In order to obtain even cheaper photosensitizers for DSSC, the metal-free organic photosensitizers are strongly desired. The metal-free organic dyes offer superior molar extinction coefficients, low cost, and diverse molecular structures as compared to the conventional Ru-dyes, In this work, we have studied on the synthesis and characterization of the organo dendritic dyes containing different number of electron acceptor moieties in a molecule.

• 전자공학회논문지A
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• 제30A권2호
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• pp.29-35
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• 1993

A guided-wave TE to TM mode converter was demonstrated by using of the off-diagonal electrooptic coefficients in LiTaO$_{3}$. The input mode is coupled to the other orthogonal mode by the electrooptically induced off-diagonal polarizability. Compared with LiNbO$_{3}$, LiTaO$_{3}$ provides a smaller birefringence and thus a larger phase match period and larger optical bnadwidth. A novel electrode structure allowed a first-order Bragg-coupling phase matching. TE/TM mode conversion efficiency of 90% at 25 [V] was demonstrated with ${\lambda}$=0.63$\mu$m He-Ne laser.