• Title/Summary/Keyword: 변동준

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Analysis of Hydrological Processes for Musim River Basin by Using Integrated Surface water and Groundwater Model (지표수-지하수 통합모형을 이용한 무심천 유역의 수문과정 해석)

  • Kim, Nam-Won;Chung, Il-Moon;Lee, Jeong-Woo;Won, Yoo-Seung
    • Journal of Korea Water Resources Association
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    • v.40 no.5
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    • pp.419-430
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    • 2007
  • Integrated modelling of surface water and groundwater has become important to satisfy the growing demands for sustainable water resources and improved water quality. In this study, the integrated model of the semi-distributed watershed model, SWA T and the fully-distributed groundwater flow model, MODFLOW is applied to Musirn river basin for the purpose of investigating its applicability to reproduce watershed-scale hydrological processes. This objective is accomplished by first demonstrating good agreement between the simulated discharge hydrographs with the measured hydrographs for the period of 2001 -2004 while simultaneously calibrating the calculated groundwater level distribution to observation wells. Next, the integrated model is used to evaluate the effect of different temporal precipitation averages on hydrodynamic processes of streamflow, percolation, recharge and groundwater discharge. Moreover, comprehensive simulations are performed to present the relationships between monthly precipitation and each hydrological component, and to analyze the temporal-spatial variability of recharge. The results show that the components are highly interrelated, and that the heterogeneity of watershed characteristics such as subbasin slope, land use, soil type causes a significant spatial variation of recharge. Overall it is concluded that the model is capable of reproducing the temporally and spatially varied surface and subsurface hydrological processes at the watershed scale.

A Study on Reactive Congestion Control with Loss Priorities in ATM Network (ATM 네트워크에서 우선권을 갖는 반응 혼잡 제어에 관한 연구)

  • Park, Dong-Jun;Kim, Hyeong-Ji
    • The Transactions of the Korea Information Processing Society
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    • v.3 no.4
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    • pp.697-708
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    • 1996
  • In this paper, we study reactive congestion control with priority in ATM network. The priority schemes for buffer access, partial buffer sharing have been investigated in order to improve the utilization of ATM network resources the network and to satisfy the most demanding traffic class. We consider in this paper a discrete-time queueing model for partial buffer sharing with two Markov modulated Poisson inputs. This model can be used to analyze the the effects of the partial buffer sharing priority scheme on system performance for realistic cases of bursty services. Explicit formulae are derived for the number of cells in the system and the loss probabilities for the traffic. Congestion may still occur because of unpredictable statistical fluctuation of traffic sources even when preventive control is performed in the network. In this Paper, we study reactive congestion control, in which each source changes its cell emitting rate a daptively to the traffic load at the switching node. Our intention is that,by incorporating such a congcstion control method in ATM network,more efficient congsestion control is established. We develope an analytical model,and carry out an approximateanalysis of reactive congestion con-trol with priority.Numerical results show that several orders of magnitude improvement in the loss probability can be achieved for the high priority class with little impact on the low priority class performance.And the results show that the reactive congestion control with priority are very effective in avoiding congestion and in achieving the statistical gain.

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A Study on the Comparison and Analysis of Debris Reduction System on Small Bridge (소교량 유송잡물 저감시설의 비교 분석 연구)

  • Kim, Sung-Joong;Jung, Do-Joon;Kang, Joon-Gu;Yeo, Hong-Koo;Kim, Jong-Tae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.3
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    • pp.31-41
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    • 2016
  • Damage to structures, such as bridge piers, are increasing rapidly due to the debris moving along rivers at the time of flooding. Therefore, the debris fin, debris deflector and debris sweeper, which are debris reduction systems, were produced in this study and an accumulation experiment was carried out on the experimental channel according to the existence of the reduction system. The debris fin is the reduction system that creates parallel flow on debris accumulated on the bridge to pass through the bridge, which was produced using wood. In addition, the debris deflector was produced using steel pipes and it has the type of detouring the direction of debris. The debris sweeper passes the debris using the magnetic force rotation of a screw-shaped cylindrical structure by water flow and it was produced using acrylic material. The experiment was carried out by analyzing the level of accumulation according to the hardness and dropping method of the debris and comparing the accumulation rate of reduction systems, and the experiment was carried out 5 times. According to the experimental results, there was a difference in the accumulation rate according to the type of reduction system and the shape of debris, and it often depended significantly on the initial shape of debris accumulation. The direct debris reduction effect on the bridge was higher in the order of the debris deflector, debris sweeper and debris fin, but in case of the debris deflector, damage, such as stream turbulence, changes in water level and river bed, and the loss of deflector can occur due to debris accumulated directly on the debris deflector. Therefore, it is necessary to design the debris deflector considering these issues.

Hemodynamics Effects of $CO_2$ Insufflation During Thoracoscopy (흉강경시 $CO_2$에 의한 혈역학적 영향)

  • 손동섭;원경준
    • Journal of Chest Surgery
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    • v.29 no.7
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    • pp.723-727
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    • 1996
  • An adequate exposure is important in thoracoscopic procedures. The insufflation of $CO_2$has been demonstrated to aid in compressing lung parenchyma, and act as a retractor when combined with changes in patient's position. However, a recent study demonstrated that $CO_2$insufflation during thoracoscopy in the pig has adverse hemodynamic consequences. We prospectively studied 12 patients undergoing thoracoscopy to evaluate the effect of $CO_2$insufflation in the clinical setting. The mean arterial pressure, heart rate, central venous pressure, arterial oxygen saturation, and end-tidal $CO_2$pressure were monitored. Measurements were determined at baseline, at the initiation of one-lung ventilation, and at intrapleural pressure of 5, 10, 15 mmHg and following results were obtained. 1) The insufflation of 5 to 15 mmHg of $CO_2$had no significant effect on the mean arterial pressure, heart rate, arterial oxygen saturation. 2) The end-tidal $CO_2$pressure rose from 31.00$\pm$1.67 mmHg to 38.49$\pm$1.82 mmHg at an intrapleural pressure of 15 mmHg(p<0.05). 3) The central venous pressure rose from 7.75$\pm$0.76 mmHg to 12.83$\pm$1.64 mmHg and 16.16$\pm$l.97mmHg at an intrapleural pressure of 10 and 15 mmHg(p<0.05). 4) The low pressure (<10 mmHg) insufflation is a safe adjunct to the conduct of thoracoscopic surgical procedures.

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The Practical Study for the Treatment of Fish Processing Saline Wastewater Using Immersed MBR (iMBR 공정을 이용한 수산물가공폐수 처리에 관한 실증적 고찰)

  • Park, Seung Kyun;Lee, Dong Jun
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.9
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    • pp.469-475
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    • 2016
  • The study is the result of an practical operation analysis for the full scale fishery product wastewater treatment plant with immersed MBR (iMBR) process. Since fishery product industries show a wide range of wastewater generation by the season, design and operation of the equalization basin are very important factor. The aeration system for the equalization basin mixing can save the chemical consumption for followed system through the restriction of acid fermentation. The concentrations of wastewater primary DAF process treated were BOD 2,291 mg/L, $COD_{Mn}$ 530 mg/L, SS 256.8 mg/L, T-N 38 mg/L, T-P 13.5 mg/L respectively. It was considered that iMBR is the most efficient biological process for high salinity content wastewater since It is irrelevant to the capability of the sludge precipitation. SADp and SADm were 0.31, $26.5m^3/hr{\cdot}m^3$ respectively. In iMBR process, the critical F/M ratio was derived at 0.08~0.10 gBOD/gMLSS by analysing the correlations between MLSS, normalized TMP and temperature. The effluent concentrations were BOD 1.8 mg/L, $COD_{Mn}$ 12.4 mg/L, SS 1.0 mg/L, T-N 7.85 mg/L, T-P 0.1 mg/L and removal efficiencies were 99.9%, 97.6%, 96.3%, 95.7%, 97.8% respectively.

The efficiency Analysis of study using brainwave measurement device (Biopac 뇌파측정 장치를 이용한 학습의 효율성 분석)

  • An, Young-Jun;Lee, Chung-Heon;Park, Mun-Kyu;Ji, Hoon;Lee, Dong-Hoon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.951-953
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    • 2015
  • Learning for thinking says the behavior of the organism changes as a result of practice or experience. It is very difficult to identify focusing ability objectively when students study. But, brain of the body is not so. EEG signal means continuously electric records of brain potential variation between two points on the scalp when brain activities take place. In types of EEG, there are delta(0~4Hz), theta(4~8Hz), alpha(8~13Hz), beta(13~30Hz) and gamma waves(30~50Hz). SMR waves and Mid-beta waves appear when focused for studying. Part for the most influence on concentrating reported that Mid-beta waves. In relation to brain activities, EEG has been actively researched for evaluating brain focus index system during learning and study. So, By using Biopac system for this study, measured brain wave was converted into FFT for extracting Mid-beta domain signals that are related to learning after giving focus invoked subjects to a small number of people. When concentrating, we measured the change in the power of the Mid-beta frequency domain and presented a correlation. Based on these results, we analyzed whether students are concentrated objectively on learning or not. and hope to offer more efficient learning method.

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Nitric Oxide/cGMP-Independent Vasorelaxation Enhanced by L-Arginine (L-Arginine의 산화질소생성과 무관한 혈관이완효과)

  • 문승호;이종은;유광재;오봉석;이동준
    • Journal of Chest Surgery
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    • v.31 no.2
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    • pp.102-107
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    • 1998
  • It has not been clear whether L-arginine plays solely a role contributing to vascular nitric oxide (NO) synthesis. To investigate the mechanisms by which L-arginine induces vasorelaxation, effects of L-arginine on the isometric tension, and tissue NOx and cyclic guanosine monophosphate(cGMP) contents were examined in the isolated rat thoracic aorta. L-Arginine induced a dose-dependent relaxation of aortic rings only with intact endothelium only. The vasorelaxation response to low concentrations of L-arginine was abolished by the pretreatment with NG-nitro-L-arginine methyl ester(L-NAME, 10-4 mol/L), whereas the relaxation caused by higher concentrations L-arginine(10-5-10-3 mol/L) was maintained and even more pronounced in the presence of L-NAME. L-Arginine did not affect the vascular tension precontracted with KCl. The vascular tissue contents of NOx/cGMP were not significantly affected by L-arginine, while they were decreased by L-NAME. L-Arginine could not completely recover the NOx/cGMP decreased by L-NAME. Methylene blue only partially antagonized the relaxation response to L-arginine. Indomethacin did not affect the L-arginine-induced vasorelaxation, whereas ouabain markedly attenuated the relaxation. It is suggested that L-arginine induces vasorelaxation not only through its contribution to NO synthesis, but also through enhancing another endothelium-dependent mechanism which is NO/cGMP-independent and cyclooxygenase- independent.

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A Study on Contents in China Statistical Yearbook of Chinese Medicine (전국중의약통계적편(全國中醫葯統計摘編)의 구성내용에 관한 연구)

  • Bae, Sun-Hee;Han, Jeong-Min;Kim, Jin-Hyun;Jang, Hyun-Chul;Kim, Chul;Yea, Sang-Jun;Kim, Sang-Kyun;Song, Mi-Young
    • Journal of Information Management
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    • v.40 no.4
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    • pp.93-108
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    • 2009
  • In order to achieve the growth of traditional Chinese medicine, the chinese government has annually released "China Statistical Yearbook of Chinese Medicine" to the world since "State Administration of Traditional Chinese Medicine of the People's Republic of China" established in 1988. It is believed that the chinese government intends to secure the early dominance of the global medical market by systematic management of its own medicine infrastructures. Although the statistics of "China Statistical Yearbook of Chinese Medicine" weren't systematically organized at the beginning, it has becoming richer, more systematic, and more standardized in the data construction and system as time has passed. Furthermore, we can take a look at China's effort to take the initiative of oriental medicine by expanding investment in several core areas - medicine resources, operation of medical instruments, service, medicine education, medicine science research, and working expenses. This article will show how china has been trying to develop the chinese medicine, focusing on two parts. One is specific analysis of the book "China Statistical Yearbook of Chinese Medicine". It is divided into analysis of its construction system, the degree of data construction, and its statistical system. The other is analysis of annual changes in areas of medicine resources, operation of medical instruments, service, medicine education, medicine science research, and working expenses.

3D Inversion of Aeromagnetic Data In an Area of Geumsan (금산지구 항공 자력탐사 자료의 3차원 역산)

  • Ko, Kwang-Beom;You, Young-Jun
    • Geophysics and Geophysical Exploration
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    • v.17 no.2
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    • pp.49-57
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    • 2014
  • 3D magnetic inversion, based on the assemblage of 2D forward modeling and inversion as a practical technique to reflect the a priori information, was conducted to investigate the spatial distribution features of black-shale related and pyrometamorphic uranium deposit and several lithological units of Ogcheon Super Group in an area of Geumsan. By using the 3D visualization technique with suitable susceptibility interval and horizontal slice map, the spatial distribution of magnetic susceptibility corresponded to the black shale related uranium bearing lithological units, Black Slate member was well coincided with a information of uranium deposit. Also, even though it is indirect indicator for the detetction of uranium deposits interbedded in Gray Hornfels member, spatial susceptibility distribution which shows the south-east magnetic linearment corresponding to the Majeon-ri formation and Dark Gray Slate were matched well. From this investigation, we inferred that maximum depth extension which Black Slate member can be separately recognized with respect to adjacent Dark Gray Slate with strong magnetic susceptibility anomaly is about 150m with reference elevation level of 306m. In addition, Majeon-ri formation located south of Black Slate member revels relatively high magnetic susceptibility range but shows high spatial susceptibility fluctation. And, as an intrusive rocks, Jurassic Biotite Granite shows relatively low magnetic susceptibility characteristics. On the contrary, Cretaceous granite distributed in soutthern part of the study area shows the relatively high susceptibility distribution.

Error Performance Analysis of Digital Radio Signals in an Electromagnetic Interference (EMI) Environment of Impulsive Noise Plus Disturbance (임펄스 잡음과 방해파에 의한 전자파 장해(EMI) 환경하에서의 디지털 무선통신 신호의 오율해석)

  • Cho, Sung-Eon;Leem, Kill-Yong;Cho, Sung-Joon;Lee, Jin
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • v.6 no.3
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    • pp.36-54
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    • 1995
  • The error performance of digital radio signals (i.e., M-ary PSK signal, DQPSK signal, MSK signal, GMSK signal) interfered by impulsive noise and electromagnetic interference (EMI) is analyzed and discussed. In analysis at first, the error rate equations have been derived in an electromagnetic interference plus impulsive noise environment. And then, the error performance has been evaluated and shown in figures as a function of carrier-to-noise ratio, carrier-to-interference ratio, impu- lsive index, gaussian noise to impulsive noise power ratio, and interference index to measure the amount of error degradation in digital radio signals. From the obtained results we have known that in the presence of m-distributed tone interference plus inpulsive noise, the more significant the electromagnetic interference amplitude varies, the more significant performance degradation is produced. The listing the digital radio signals from the most degraded to the least is that DQPSK, GMSK, QPSK and MSK signal. In the constant amplitude tone interference plus impulsive noise environment, the effect of in- terference nearly disappears over about 20dB in CIR. The effect of constant tone interference on error rate performance is reduced more remarkably in the region from 10dB to 15dB in CIR. In both enviroments of m-distributed tone interference and constant amplitude tone interference, the more electromagnetic interference amplitude varies and CIR increases, the more error perfor- mance is improved. But it is found out that the performance can not be improved significantly even the electromagnetic interference becomes weak. This describes that the impulsive noise affects dominantly to the performance degradation.

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