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Latent Heat Flux over the Global Ocean

  • Kubota, Masahisa
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.644-648
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    • 2002
  • Though it was difficult of globally monitor latent heat flux aver the ocean for many years, the situation is rapidly changing by the use of satellite data. Since a bulk formula is used to estimate turbulent heat flux using satellite data, we need wind speed, sea surface temperature and specific humidity data. However, it is not easy to accurately estimate specific humidity using satellite data. Now several algorithms for estimating specific humidity have been proposed and applied to construct latent heat flux data sets. Latent heat flux data sets derived from satellite data such as J-OFURO, HOAPS and GSSTF are available at present. Since the algorithm and used satellite data are not the same between them. the characteristics of each data set may be different. Therefore, it is important to clarify the difference between each data set and investigate the cause of the difference in latent heat flux estimates. In this paper we summarize the present state of the art with regard to the turbulent heat flux estimation by using satellite data. Also we present the comparison results of latent heat flux fields including not only satellite-derived flux fields but also analysis fields.

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Energy Performance Comparison of Electric Heater and Geothermal Source Heat Pump type Agricultural Hot Air Dryers (전기히터식 및 지열원 히트펌프식 농산물 열풍건조기의 에너지 성능 비교)

  • Yang, Won Suk;Kim, Young Il;Park, Seung Tae
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
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    • v.14 no.4
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    • pp.7-12
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    • 2018
  • Energy performance of electric heater and geothermal source heat pump type hot air dryers are compared in this study. For set temperatures of $30^{\circ}C$, $35^{\circ}C$ and $40^{\circ}C$, radish is dried from initial mass 60 kg until it gets 5 kg, where the difference equals the amount of water removed. As set temperature is increased, drying time is shortened for both electric heater and heat pump types, however energy efficiency is decreased due to increasing electricity consumption. Moisture extraction rate(MER) of electric heater is 2.58~2.84 kg/h, and for heat pump type 2.56~2.71 kg/h, showing little difference between the two types. Specific moisture extraction rate (SMER) of electric heater is 0.94~0.96 kg/kWh, and for heat pump type 1.72~2.21 kg/kWh. SMER of heat pump type is greater by 0.78~1.25 kg/kWh than the electric heater hot air dryer, which is 1.8~2.3 times better in terms of energy efficiency.

Effects of Bridge Exercise Combined with Vibration on Abdominal Muscle Thickness (진동을 병행한 교각운동이 복부 근육 두께에 미치는 영향)

  • Jae Cheol Park;Jin Gyu Jeong
    • Journal of Korean Physical Therapy Science
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    • v.30 no.3
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    • pp.31-40
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    • 2023
  • Background: The purpose of this study was to confirm the effect of bridge exercise combined with vibration on abdominal muscle thickness. Design: Randomized controlled trial. Methods: As study subjects, 24 adults in their 20s were classified into 12 vibration bridge exercise groups and 12 bridge exercise groups. The time was divided into before the experiment, 3 weeks after the experiment, and 6 weeks after the experiment. Two-way repeated ANOVA was used to examine changes in the muscle thickness of the external oblique, internal oblique, and transverse abdominal muscles of the trunk muscles, and the significance level was set at 0.05. If there was an interaction between time and group, post-hoc analysis was performed, and the significance level was set at 0.01. Results: There was a significant difference in the external oblique muscle in the change by period, the interaction between time and group, and the change between groups (p<0.05). There was a significant difference in the external oblique muscle in the change by period, the interaction between time and group, and the change between groups (p<0.05). Conclusion: As a result of this study, bridge exercise combined with vibration had a positive effect on the muscle thickness of the external oblique, internal oblique, and transversus abdominis muscles. It suggests the possibility of using the basic data of vibration exercise and the lumbar stabilization exercise in clinical practice.

A Study on the Road Traffic Noise Restriction Factors that Affect the Price of Apartment Complexes (아파트 가격에 영향을 미치는 도로교통소음 제한인자에 관한 연구)

  • Park, Sang-Ill;Choi, Hyung-Il;Cheong, Kyung-Hoon;Jung, Sang-Chul
    • Journal of Environmental Science International
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    • v.18 no.4
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    • pp.389-400
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    • 2009
  • In this research, we measured the number of lanes, distance, disposition of apartment that are affecting the road traffic noise to evaluate the current condition of G city's road traffic noise. We decide on a basis regarding an apartment price formation factor, and the apartment current price and the results that compared. To have a point scale, we set the maximum road traffic noise at a 8 lane road for 5 points, give 4 points for a 6 lane road, which has a $2.1{\sim}2.5\;dB(A)$ difference compared to a 8 lane road, give 3 points for a 4 lane road, which has a $5.2{\sim}5.5\;dB(A)$ difference compared to a 8 lane road, and set 2 points for a 2 lane road and lower. If we set the standard floor plan as horizontal and a living room facing the roadside, the horizontal and living room facing the opposite side of the road is 1 point because it differs by 14.1 dB(A), and the vertical is 3 points since the difference is 5.3 dB(A). If we make grades by the distance, making standard the fifth floor with little soundproof effect from apartment to road, we observe a measurement below 2.9 dB(A) at a distance of less than 10 m and 5 dB(A), decreased at a distance of 20 m. Therefore, 4 points were given for less than 10m, 3 points for $10{\sim}20\;m$, 2 points for more than 20 m as we can apply the effect of a decay distance of line sound source and the decrease in noise effects of more than 6 dB(A), 1 point for more than 40m, and 0 points for more that 80 m since it is negligible. 28 apartments got 0 points because there is no effect of road traffic noise from other apartments, and 50 apartments where only the road at one side effect them got $5{\sim}10$ points. 4 apartments (17-2, 6-3, 10-4, 3-3) received over 20 points. 15 cases showed a difference between developer price and resale price, and 11 cases (73%) among them showed the same trend (price increases with a low road traffic noise restriction factor point) with the point of road traffic noise restriction factor. 4 cases demonstrated the opposite trend, showing price increases with a high restriction factor point. Among the 4 cases, case numbers 2,6 and 9 appear to be more affected by the location factor (business district) than the road traffic noise restriction factor, and case number 1 appears to be affected by the building factor (openness and direction).

Accuracy Evaluation of Supervised Classification about IKONOS Imagery using Mixed Pixels (혼합화소를 이용한 IKONOS 영상의 감독분류정확도 평가)

  • Lee, Jong-Sin;Kim, Min-Gyu;Park, Joon-Kyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.6
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    • pp.2751-2756
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    • 2012
  • Selection of training set influences the classification accuracy in supervised classification using satellite imagery. Generally, if pure pixels which character of training set is clear were selected, whole accuracy is high while if mixed pixels were selected, accuracy is decreased because of low-resolution imagery or unclear distinguishment. However, it is too difficult to choose the pure pixels as training set actually. Accordingly, this study should be suggested the suitable classification method in case of mixed pixels choice. To achieve this, a few pure pixels were chosen as training set and classification accuracy was calculated which was compared with classification result using an equal number of mixed pixels. As a result, accuracy of SVM was the highest among the classification method using mixed pixels and it was a relatively small difference with the result of classification using pure pixels. Therefore, imagery classification using SVM is most suitable in the mixed area of construction and green because it is high possibility to choose mixed pixels as training set.

A Study on the Color Membership Computation Method using Fuzzy Color Model (패지 컬러 모델을 이용한 컬러의 소속 정도를 결정하는 방법에 관한 연구)

  • Kim, Dae-Won;Lee, Kwang. H.
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.04b
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    • pp.262-264
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    • 2002
  • In this paper we focused on the color representation prob1em based on fuzzy set theory. The main factor is the determination or computation of color membership function and color difference formula. The mathematical formula to calculate the color difference should generate a uniform color scaling, and due to this reason we adopted a CIELAB color- space as a fundamental feature space. With the help of the CIELAB color space we created a new color model, referred to fuzzy color model, which can represent the ambiguous characteristics underlying colors. Based on the proposed color difference formula between fuzzy colors, we could obtain the membership computation method of an arbitrary color for a given color family.

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An Investigation of Lattice Boltzmann Multi-phase Model and it Application (래티스볼츠만 다상류 모델의 검토 및 응용)

  • Kang, Ho-Keun;Ahn, Soo-Whan
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2006.06a
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    • pp.269-270
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    • 2006
  • A finite difference lattice Boltzmann model which allows us to simulate gas-liquid two-phase flows with large density difference, for instance, 800 times for air and water is considered. Two-particle model is used and the density difference is introduced by changing the acceleration according to the fluid density. Numerical measurement of surface tension agrees well with theoretical predictions. Simulations of two-phase phenomenon for phase-transition is carried out, showing applicability of the model for two-phase flows. The two-dimensional cavitating flow around a board set up in the fluid way is also simulated. As a result, it was confirmed that the FDLB method with two-particle model was effective in numerical simulation of cavitating flow and the bubble periodically grew up at the low pressure area behind the board, in which the fluid condition was influenced by the cavitation number.

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The Effect of Lower Weight Training on Bone Mineral Density and Body Composition in Old-Aged Women (저강도 웨이트 트레이닝이 여성노인의 골밀도와 신체조성에 미치는 영향)

  • SHIN, Koun Soo;JANG, Byung Ho
    • Journal of Fisheries and Marine Sciences Education
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    • v.28 no.1
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    • pp.118-126
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    • 2016
  • The purpose of this study is for old-aged women to analysis variation of Body composition and BMD so that help to keep healthy life by doing low-intensity workout. the subjects for this study consist of 20 persons being aged over 65 women, doing not regular workout, living in P metropolitan, and do workout for 12 weeks by catergorizing into 2 groups in half depending upon whether doing workout or not. Two-way Repeated Measures ANOVA of SPSS 18.0 was used for data processing. the statistical significant is set as p<.05. In result, there's none of dramatical difference in radius, ulna's BMD. there is dramatical difference in (%)Fat, WHR in workout group but none difference in LBM.

Temperature Limitation for Safe Operation in a Slab Laser Glass Set by Thermal Frature (열적 파괴로 인한 슬랩 레이저 글라스에서의 안전 작동을 위한 온도 제한)

  • 김병태
    • Korean Journal of Optics and Photonics
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    • v.4 no.3
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    • pp.354-358
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    • 1993
  • The temperature distribution inside a zigzag slab laser glass was measured using a Mach-Zehnder interferometer. The temperature difference between the center and the surface of the slab caused the fracture of the slab glass. Two laser glasses were fractured at a temperature difference ${\Delta}T_0$of TEX>$110^{\circ}C$, $62^{\circ}C$ respectively. For the design of high-average power glass laser, it is recommended that the limit of the temperature difference ${\Delta}T_0$ inside the slab glass should be smaller than $50^{\circ}C$ for safe operation.ration.

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Implemenation of an ASIP for acceleration SAD operation (SAD 연산의 가속을 위한 멀티미디어 코프로세서 구현)

  • Jo, Jung-Hyun;Jeong, Ha-Young
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.809-810
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    • 2006
  • An H.264 algorithm is commonly used for video compression applications. This algorithm requires a large number of data computations, for example, the sum of absolute difference (SAD) operation. We analyzed H.264 reference encoding workloads. The H.264 encoding program has 8.78% SAD operation. The SAD operation is to sum up 16 difference-values in H.264 $4{\times}4$ sub-blocks. In order to accelerate SAD operations, we implemented an application specific instruction-set processor (ASIP) that can execute SAD and data transfer instructions. The proposed coprocessor has an absolute value generator and a carry save adder (CSA) unit to sum up 8 difference-values per one clock cycle. We completed SAD operation in 2 clock cycles. Experimental results show that the performance is improved by 34% of total execution time.

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