• Title/Summary/Keyword: Zero energy

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Development of Curriculum for Dept. of Environmental Education toward a Sustainable Green Society (지속가능한 녹색 사회를 향한 환경교육과 교육과정 개발)

  • Choi, Don-Hyung;Kim, Dae-Hee;Lee, Jae-Young;Cheong, Cheol;Kim, Kee-Dae;Cho, Seong-Hoa;Ahn, Jae-Jung;Park, Hye-Gyeong;Hong, Hyun-Jin
    • Hwankyungkyoyuk
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    • v.24 no.4
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    • pp.111-128
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    • 2011
  • This study was aimed at developing a common curriculum for the department of environmental education from 5 colleges of education. The need and background of curriculum reform can be summarized as follow; first, it has been recognized that new national curriculum of 2009 and 2011 created need for training teachers equipped with more integrated competency. Second, global environmental problems such as climate change and energy crisis asked for more responsible choice and action from all citizens. Third, the extremely low hiring rate resulted in the consideration of new working fields for teacher students majoring in environmental education. Fourth, the expansion of new environmental education paradigms including education for sustainable development called for practicing reconstruction of both contends and methods. From a series of research processes including analysis of current curriculum, DACUM, opinion survey and interest groups review, several new approaches for developing new curriculum had been identified as follow; first, content areas of environmental education should be extended beyond environmental natural science. Second, new learning approaches such as project-based learning need to be emphasized for strengthening the identity of environment as a separate subject. Third, more selective majoring system need to be applied in connection with environment government officials, researchers, and social environmental educators. It was recommended that the application of new curriculum developed by the study would be evaluated and managed by teaching conditions surrounding each of the five university members joined this developing processes. However, it needs to be noted that there is not much time because we had experienced zero hiring rate for the last 4 years and environmental policy and education programs are moving rapidly toward sustainable development.

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In Vitro and In Vivo Agreement of Microwave Radio-Thermometer and Needle Probe Thermometer During Therapeutic Ultrasound (초음파 가열 시 In Vitro 및 In Vivo에서 Microwave Radio-Thermometer와 탐침온도계의 일치도)

  • Lee, Su-Young;Cho, Sang-Hyun;Yi, Chung-Hwi;Kim, Jong-Man
    • Physical Therapy Korea
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    • v.10 no.1
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    • pp.15-27
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    • 2003
  • Therapeutic ultrasound is commonly applied for deep heating in physical therapy setting. However, it is difficult to determine the exact application dosage and to confirm the immediate heating effect. Microwave Radio-Thermometer (MRT) can measure the temperature by the electromagnetic energy in the microwave region of the object that emits above absolute zero temperature. MRT was used for early diagnosis of breast cancer since it was not harmful, non-invasive, and non-ionizing to the human body. The purposes of this study were to investigate how accurately 1.1 GHz RTM (RES Ltd. Russia) measures the change of average temperature in the tissue, and to determine the depth of temperature change measurement. Therapeutic ultrasound was applied (continuous wave for 5 minutes, 1 MHz, intensity of 1.5 $W/cm^2$ [in vitro] and 1.0 $W/cm^2$ [in vivo]) in four different conditions: (1) 30 cases of in vitro specimen of pork, (2) 30 cases of in vitro specimen of pork ankle joint, (3) 10 cases of in vivo canine thigh, and (4) 30 cases of in vivo human body. Intraclass Correlation Coeffients (ICC[3,1]) between average needle probe thermometer below surface and MRT temperature was revealed as followed: (1) Before ultrasound application ICCs ranges above .8 in specimen of pork (15 mm underneath the skin) and above .82 in specimen of pork ankle joint (10~30 mm underneath the skin). (2) After ultrasound application ICCs ranges above .7 in both specimens of pork and pork ankle joint. (3) Before ultrasound application ICCs ranges above .8 in canine thigh (20 mm underneath the skin). (4) After ultrasound application ICCs ranges above .82 in canine thigh. The temperature of the human body increased significantly with the mean of $15^{\circ}C$ in muscle tissue and with the mean of $3.5^{\circ}C$ in joint (p<.00). It was revealed that the average depth of temperature measurement of the tissue by MRT was in between 10 and 35 mm, and determined that the proper temperature measurement band was $36.5{\sim}37.0^{\circ}C$.

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Mathematical Analysis on TTI's Estimation Accuracy of Food Shelf Life Depending on its Discrepancy in Temperature Dependence (상호 온도의존성의 차이에 따른 TTI의 식품 shelf life 예측 정확성에 대한 수리적 분석)

  • Kang, Jin Won;Choi, Jung Hwa;Park, Soo Yeon;Kim, Min Jung;Kim, Min Jung;Lee, Man Hi;Jung, Seung Won;Lee, Seung Ju
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.20 no.3
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    • pp.85-89
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    • 2014
  • TTI is a small label of which the color changes by time-temperature history during food storage. The food shelf life (SL) was compared with that of TTI, the time for TTI to reach the end-point of its color change, for the various discrepancies in two Arrhenius activation energies (Ea), an important parameter of temperature dependence. The SL of TTI and food were mathematically simulated, based on zero-order and first-order kinetics, respectively. In the case Ea of food was smaller than that of TTI, the SL of food was larger than that of TTI, meaning TTI reaches the end-point of color change earlier even though food is still fresh. In the case of Ea of food > Ea of TTI, the food reaches the SL earlier than the TTI. In addition, the magnitude of ${\Delta}Ea$ between food and TTI led to the bigger ${\Delta}SL$. To be safe, $SL_{Food}$ > $SL_{TTI}$ would be practical although $SL_{Food}{\fallingdotseq}SL_{TTI}$ is ideal.

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Construction of an Underground Heat Exchanger for Pig Housing (양돈용 지열교환기의 개발)

  • ;;H. J. Heege
    • Journal of Animal Environmental Science
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    • v.1 no.2
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    • pp.125-136
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    • 1995
  • To use the earth heat for the pig housing, an underground heat exchanger has constructed in depth of 2.5m and 20m length. The temperature of the outlet air was max. 8 kelvin higher than that of inlet air in winter season. In spite of the -7$^{\circ}C$ outside temperature, it could keep the air temperature from the earth tube above zero degree. The heating performance was maximum in value of 3.25Wh/㎥ and average of 1.75Wh/㎥ by the airflow volume of 340㎥/h. The slope of relative humidity from outlet air has shown gentler than that of inlet air. By using the underground heat exchanger, it would be possible to prepare an relatively uniform relative humidity in the swine stalls. The temperatures on the earth, where PVC pipes are buried, have shown 10~12$^{\circ}C$ on March. This can reduce the difference between day and night temperature during this season by using the underground heat exchanger.

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Effects of Water Temperature and Feeding Rate on Growth and Body Composition of Grower Olive Flounder Paralichthys olivaceus (사육 수온 및 사료 공급율이 넙치의 성장 및 체조성에 미치는 영향)

  • KIM, Kyoung-Duck;KIM, Kang-Woong;LEE, Bong-Joo;HAN, Hyon-Sob
    • Journal of Fisheries and Marine Sciences Education
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    • v.28 no.3
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    • pp.611-618
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    • 2016
  • A $3{\times}2$ factorial experiment was conducted to investigate effects of water temperature and feeding rate on growth and body composition of olive flounder. Triplicate groups of fish (initial body weight of 118 g) fed a extruded pellet (55% protein and 4708 cal/g) to satiation and at restricted feeding rates of 0.25 and 0.4% body weight per day (BW/d) at the different water temperatures (13 and $18^{\circ}C$) for 9 weeks. Weight gain increased significantly with increase in feeding rates at each temperature. Weight gain of fish fed to satiation was significantly higher at 18 than $13^{\circ}C$, whereas, that of fish fed at 0.25 and 0.4% BW/d were significantly or slightly lower at 18 than $13^{\circ}C$. Feed efficiency and protein efficiency ratio of fish fed to satiation were not significantly different between 13 and $18^{\circ}C$, but those of fish fed at 0.25 and 0.4% BW/d were significantly higher at 13 than $18^{\circ}C$. The major finding of this study is that satiation feeding is efficient for optimal growth and feed efficiency of grower oliver flounder (116-164 g) in suboptimal water temperatures. The maintenance feeding ration which is zero growth performance, were 0.30 and 0.41% BW/day at 13 and $18^{\circ}C$, respectively. In the restricted feeding regime, compromised growth of fish were worsen in higher water temperature ($18^{\circ}C$ vs. $13^{\circ}C$). It might be related to high metabolic rate of fish that spend more energy for maintenance metabolism. Based on these results, we suggest that a satiation feeding regime is recommended for a productive growth of grower olive flounder in the suboptimal temperature.

Stability of Haptic System with consideration for Sample-and-Hold Methods and Properties of Haptic Device (샘플-홀드 방식과 햅틱 장치 물성치에 따른 햅틱 시스템의 안정성 분석)

  • Lee, Kyungno
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.11
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    • pp.5338-5343
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    • 2013
  • In a haptic system, a virtual wall is modeled as a virtual spring. The larger the stiffness of the virtual spring is, the more improved the reality of the virtual wall is, but the more unstable the haptic system becomes. This paper shows how to increase the stiffness of the virtual spring while the stability of the haptic system is guaranteed and shows the effects of a mass (Md) and a damper (Bd) of a haptic device on the stability when first-order hold method is applied and a virtual wall is modeled as a virtual spring (Kw). The simulation results show the boundary of the virtual spring is proportional to the square root of the mass (Md) and the damper (Bd) while maintaining the stability. The relation among the virtual spring (Kw), the mass (Md) and the damper (Bd) of the haptic device, and sampling time (T) is inferred as $K_w{\leq}{1.611M_d}^{0.50}{B_d}^{0.50}T^{-1.51}$, by using the simulation results. The maximum available stiffness of the virtual spring in first-order hold method is larger than in zero-order hold method. So the reality of the virtual wall can be improved.

Design of video encoder using Multi-dimensional DCT (다차원 DCT를 이용한 비디오 부호화기 설계)

  • Jeon, S.Y.;Choi, W.J.;Oh, S.J.;Jeong, S.Y.;Choi, J.S.;Moon, K.A.;Hong, J.W.;Ahn, C.B.
    • Journal of Broadcast Engineering
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    • v.13 no.5
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    • pp.732-743
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    • 2008
  • In H.264/AVC, 4$\times$4 block transform is used for intra and inter prediction instead of 8$\times$8 block transform. Using small block size coding, H.264/AVC obtains high temporal prediction efficiency, however, it has limitation in utilizing spatial redundancy. Motivated on these points, we propose a multi-dimensional transform which achieves both the accuracy of temporal prediction as well as effective use of spatial redundancy. From preliminary experiments, the proposed multi-dimensional transform achieves higher energy compaction than 2-D DCT used in H.264. We designed an integer-based transform and quantization coder for multi-dimensional coder. Moreover, several additional methods for multi-dimensional coder are proposed, which are cube forming, scan order, mode decision and updating parameters. The Context-based Adaptive Variable-Length Coding (CAVLC) used in H.264 was employed for the entropy coder. Simulation results show that the performance of the multi-dimensional codec appears similar to that of H.264 in lower bit rates although the rate-distortion curves of the multi-dimensional DCT measured by entropy and the number of non-zero coefficients show remarkably higher performance than those of H.264/AVC. This implies that more efficient entropy coder optimized to the statistics of multi-dimensional DCT coefficients and rate-distortion operation are needed to take full advantage of the multi-dimensional DCT. There remains many issues and future works about multi-dimensional coder to improve coding efficiency over H.264/AVC.

Geotechnical Characteristics of the Ulleung Basin Sediment, East Sea (1) - Cosolidation and Shear Waves Velocity (동해 울릉분지 심해토의 지반공학적 특성(1) - 압밀 특성, 전단파 특성에 관한 연구)

  • Kim, Youngmoon;Lee, Jongsub;Lee, Jooyong;Lee, Changho
    • Journal of the Korean GEO-environmental Society
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    • v.14 no.5
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    • pp.33-39
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    • 2013
  • A drilling exploration in deep sea is being processed to develop new energy resource in the world. In 2007, the presence of the gas hydrate had been confirmed during the UBGH1 (Ulleung Basin Gas Hydrate Expedition 1) in the Ulleung Basin. Geotechnical properties of the deep marine sediment are important factors for assessing the safety of gas production facility and productivity from the hydrate bearing sediment. In this study, comprehensive laboratory tests are conducted to investigate the geotechnical engineering characteristics of the deep marine sediments recovered from the hydrate occurrence regions during the UBGH2 (Ulleung Basin Gas Hydrate Expedition 2) in the Ulleung Basin, East Sea, Korea. The index properties of the specimens including the specific gravity, atterberg limits, specific surface, and particle size distribution are measured, and these are compared to the results reported by previous studies. A zero-lateral strain cell, which houses bender elements, is used to determine stress-dependant characteristics and shear wave velocities with the vertical effective stresses. Furthermore, the hydraulic conductivity is calculated based on the consolidation test results.

Comparison of Monitor Units Obtained from Measurements and ADAC Planning System for High Energy Electrons (측정과 ADAC 치료계획 시스템에서 계산된 고에너지 전자선의 Monitor Unit Value 비교)

  • Lee, Re-Na;Choi, Jin-Ho;Suh, Hyun-Suk
    • Progress in Medical Physics
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    • v.13 no.4
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    • pp.202-208
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    • 2002
  • The purpose of this study is to evaluate the monitor unit obtained from various methods for the treatment of superficial cancers using electron beams. Thirty-three breast cancer patients who were treated in our institution with 6, 9, and 12 MeV electron beams, were selected for this study. For each patient, irregularly shaped treatment blocks were drawn on simulation film and constructed. Using the irregular blocks, monitor units to deliver 100 cGy to the dose maximum (dmax) were calculated from measurement and three-dimensional radiation treatment planning (3D RTP) system (PINNACLE 6.0, ADAC Laboratories, Milpitas CA) Measurements were made in solid water phantom with plane parallel (PP) chamber (Roos, OTW Germany) at 100 cm source-to surface distances. CT data was used to investigate the effect of heterogeneity. Monitor units were calculated by overriding CT values with 1 g/㎤ and in the presence of heterogeneity. The monitor unit values obtained by the above methods were compared. The dose, obtained from measurement in solid water phantom was higher than that of RTP values for irregularly shaped blocks. The maximum differences between monitor unit calculated in flat water phantom at gantry zero position were 4% for 6 MeV and 2% for 9 and 12 MeV electrons. When CT data was used at a various gantry angle the agreement between the TPS data with and without density correction was within 3% for all energies. These results indicate that there are no significant difference in terms of monitor unit when density is corrected for the treatment of breast cancer patients with electrons.

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Time-domain Seismic Waveform Inversion for Anisotropic media (이방성을 고려한 탄성매질에서의 시간영역 파형역산)

  • Lee, Ho-Yong;Min, Dong-Joo;Kwon, Byung-Doo;Yoo, Hai-Soo
    • 한국지구물리탐사학회:학술대회논문집
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    • 2008.10a
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    • pp.51-56
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    • 2008
  • The waveform inversion for isotropic media has ever been studied since the 1980s, but there has been few studies for anisotropic media. We present a seismic waveform inversion algorithm for 2-D heterogeneous transversely isotropic structures. A cell-based finite difference algorithm for anisotropic media in time domain is adopted. The steepest descent during the non-linear iterative inversion approach is obtained by backpropagating residual errors using a reverse time migration technique. For scaling the gradient of a misfit function, we use the pseudo Hessian matrix which is assumed to neglect the zero-lag auto-correlation terms of impulse responses in the approximate Hessian matrix of the Gauss-Newton method. We demonstrate the use of these waveform inversion algorithm by applying them to a two layer model and the anisotropic Marmousi model data. With numerical examples, we show that it's difficult to converge to the true model when we assumed that anisotropic media are isotropic. Therefore, it is expected that our waveform inversion algorithm for anisotropic media is adequate to interpret real seismic exploration data.

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