• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.182-185
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• 2011

Soil $NH_4$-N content became higher in proportion to the increase in the urea application rate, while in livestock faeces compost (LFC) plots, it became lower than in urea plots and had no significant difference statistically among LFC plots. There was a close relationship between phosphate fertilization rate and the increment of soil available phosphate content after experiment resulting y=0.1788x-6.169 ($R^2=0.9425$) when applied fused superphosphate fertilizer, and y=0.0662x-2.689 ($R^2=0.9315$) when applied LFCs by the same amounts of phosphate (x: phosphate application, kg $ha^{-1}$, y: increment in soil available phosphate content, mg $kg^{-1}$. Plant height, number of stems, nutrients uptake by rice and rice yield showed higher levels in N 100, 150% application plots of chemical fertilizers, while every LFC plots exhibited lower values and no significant difference among them. Relative nitrogen fertilization efficiencies of LFCs compared to urea was 12.3% for cattle faeces compost (CaFC), 8.8 for swine faeces compost (SwFC) and 24.6 for chicken faeces compost (ChFC), respectively.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1104-1108
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• 2006

The purpose of this study was to investigated the effects of Laminaria japonica fucoidan extract (LJFE) through the enzymatic regulation against the hepatotoxicity-inducing carbon tetrachloride $(CCl_4)$ in LJFE and $CCl_4-treated$ rats. LJFE of 100mg/kg concentration was intraperitoneally administered into rats at dose of 1.5m11kg for 14 days. On the day 15, 3.3ml/kg of $CCl_4$ dissolved in olive oil (1:1) was injected 12 hours before anesthetization. We examined the levels of glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) in serum of rats, superoxide dismutase(SOD) in mitochondrial fraction, and catalase(CAT), glutathione peroxidase(GPx) in liver homogenate. $CCl_4-treatment$ markedly increased the levels of GOT and GPT, and significantly decreased those of SOD, CAT and GPx. But LIFE pretreatment decreased the levels of GOT and GPT, by 40% and 64%, respectively and increased those of SOD, CAT and GPx, by 114%, 36.1% and 55.9%, respectively These results showed the LIFE had the enzymatic regulatory effects against the hepatotoxicity-inducing $CCl_4$ in the preventive way.

• Advances in Energy Research
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• v.5 no.1
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• pp.79-90
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• 2017

The main objective of load frequency control (LFC) is to keep the frequency value at nominal value and force deviation of the frequency to zero in case of load change. This paper suggests LFC by using a model predictive control (MPC), based on Integral Square Error (ISE) method designed to optimize the damping of oscillations in a two-area power system. The MPC is designed and simulated with a model system in state space, for robust performance in the system response. The proposed MPC is tuned by ISE to achieve superior efficiency. Moreover, its performance has been assessed and compared with the PI and PID conventional controllers. The settling time and overshoot with MPC are extremely minimized as compared with conventional controllers.

• Proceedings of the Korea Multimedia Society Conference
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• 2000.04a
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• pp.386-389
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• 2000

인터넷이 급속도로 발전되면서 트래픽이 폭발적으로 증가하여 현재 라우터에 많은 부담을 주고 있다. 반면 스위칭 기술은 라우팅보다 빠르게 데이터를 전송할수 있다. 그 결과 라우터 병목 현상을 해결하고자 IP 라우팅이 스위칭 기술을 접목한 레이블 스위칭 네트웍이 출현하게 되었다. 레이블 스위칭 기술중 데이터 기반 레이블 스위칭에서 매우 중요한 것은 캐쉬 테이블 관리이다. 캐쉬 테이블에는 흐름 분류를 위한 정보와 레이블 스위칭을 위한 정보를 저장하고 있는데 캐쉬 테이블 크기는 라우터자원에 의해 제약을 받으므로 캐쉬 대체기법이 필요하게 된다. 따라서 효율적이 캐쉬테이블 관리를 위해 인터넷 트래픽 특성을 고려한 캐쉬 대체 기법에 관한 연구가 필요하다. 본 논문에서는 인터넷 트래픽 특성을 고려해 LFC 기법과 LRU 기법의 단점을 보완한 L2A 캐쉬 대체 기법을 제안한다. L2A 기법은 기본적인 FIFO , LFC, LRU 기법보다 나은 성능을 보이며 특히 캐쉬 크기가 작을 경우에도 타 기법에 비해 탁월한 성능을 유지한다.

• Progress in Superconductivity and Cryogenics
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• v.15 no.1
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• pp.19-24
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• 2013

In this paper, the Superconductor flywheel energy storage system (SFESS) was used for the load frequency control (LFC) of an interconnected 2 area power system. The robust SFESS controller using quantitative feedback theory (QFT) was designed to improve control performance in spite of parameter uncertainty and unexpected disturbances. An overlapping decomposition method was applied to simplify SFESS controller design for the interconnected 2 area power system. The model for simulation of the interconnected 2 area power system included the reheat steam turbine, governor, boiler dynamics and nonlinearity such as governor deadband and generation rate constraint (GRC). To verify robust performance of proposed SFESS controller, dynamic simulation was performed under various disturbances and parameters variation of power system. The results showed that the proposed SFESS controller was more robust than the conventional method.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.05a
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• pp.142-145
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• 2000

A new robust load-frequency control (LFC) methodology is proposed for nonlinear power systems with the valve position limits of the governor in the presence of parametric uncertainties. The Takagi-Sugeno (TS) fuzzy model is adopted for fuzzy modeling of the nonlinear power system. A sufficient condition of the robust stability is presented in the sense of Lyapunov for the TS fuzzy model with parametric uncertainties. The intelligent digital redesign technique for the uncertain nonlinear power system is also studied. The effectiveness of the proposed robust fuzzy LFC controller design method is demonstrated through a numerical simulation.

• Journal of the Korean Solar Energy Society
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• v.40 no.1
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• pp.1-13
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• 2020

A study on estimation of the Levelized Cost of Energy (LCOE) was conducted for the Korean onshore wind farms. The LCOE was estimated on the basis of the actual wind farm data from Data Analysis, Retrieval Transfer system (DART) run by Financial Supervisory Service. Recently, social discount rate of Korea dropped from 5.5% to 4.5%, which was taken into account for this study. The onshore wind farms studied accounted for 42% of all the onshore wind farms of South Korea. Capital Expenditure (CapEx) and Operation Expenditure (OpEx) were calculated from the actual data, while Capacity Factors (CFs) were obtained from the wind farms of five provinces. Their distributions were estimated using Maximum Likelihood Estimation method, and then Monte Carlo Simulation (MCS) was performed for estimating LCOE, Levelized Fixed Cost (LFC), and Levelized Variable Cost (LVC). As a result, the LCOEs at the two discount rates, 4.5 and 5.5%, were 142 and 152 $/MWh, respectively, which were lower than that of financially viable onshore wind project of Korea. The 1% drop of social discount rate was estimated to result in a 10 $/MWh decrease in LCOE and a 4 $/MWh in LFC, which can be an advantage for wind project investors.

• The Journal of Korean Obstetrics and Gynecology
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• v.18 no.3
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• pp.92-109
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• 2005

Purpose : The Purpose of this research was to investigate the effects of Cheongyeolhawlhyeoltanggagyehyeoldeung (CYHHT) on anti-inflammatory effects. Methods : As for the parameters of inflammation, levels of several inflammatory cytokines and chemical mediators were determined in mouse lung fibroblast cells(mLFC) and RAW264.7 cells. Also, changes in pathological features by drug treatment were investigated in the in vivo edema-induced rats by carrageenin /arachidonic acid or in the colitis-induced mice by DSS treatment. Results : The cytotoxicity of CYHHT on mLFC and RAW264.7 cells was not observed at 100, 50, 10, and $1{\mu}g/ml$ of CYHHT treatments. $IL-1{\beta}$, IL-6 and NOS-IImRNA expression of RAW264.7 cells was inhibited by CYHHT treatments in a dose-dependent manner. CYHHT treatment of RAW264.7 cells inhibited $TNF-{\alpha}$ and COX-2 mRNA expression. CYHHT treatment of RAW264.7 cells significantly inhibited IL-6 and NO production. CYHHT treatment of RAW264.7 cells inhibited ROS production. CYHHT inhibited rat's paw edema induced by carrageenin or arachidonate treatment in all concentrations examined. The body weight and colon length of colitis-induced mice were recovered to a normal level by DSS treatment. Clinical disease levels were significantly improved compared to the control animals. CYHHT treatment of colitis-induced mice significantly increased hematological values such as WBC and RBC counts, Hgb and HCT levels, but decreased PLT values. CYHHT treatment of colitis-induced mice decreased IL-6 and $TNF-{\alpha}$ production significantly CYHHT treatment of colitis-induced mice significantly increased CD3+(T) cell counts. In contrast, CYHHT treatment decreased CD19+ B cell counts and CD3+/CD69+ significantly, and also decreased B/T ratio (%) though not significant. Conclusion : These results indicated that CYHHT could be used for treating diverse female diseases caused by the inflammation.

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.109-130
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• 2002

The purpose of this paper was to make a comparative analysis for the difference of the various kinematic variation which is occurred in the each situation when pitchers throw a straight and a curve ball. Four pitchers, who are two national team players and two high level pitchers, were selected among the right over hand pitchers of D university in the Busan for this paper. The data were analyzed by using 3D equipment. The results of the analysis which was about the elapsed time of the pitching, the movement of the body center-point, the highest height of the left knee, stride length, knee joint angle, shoulder joint angle, elbow joint angle and wrist joint angle in the each section(ST, LKU, HBP, LCF, MCP, BRP) were as follows : 1. Pitching time in the each section and step in the pitching for straight and curve ball was similar. The total elapsed time of the straight and curve ball was 1.78${\pm}$0.07sec and 1.77${\pm}$0.11sec in the order. 2. The position change of the body center to the Z(above below) direction did not show significant difference in the each situation of the section and step between pitching for the straight and curve ball. 3. Height of the left knee did not show significant difference as 125.38${\pm}$11.85cm and 124.95${\pm}$11.63m in the each pitching motion for straight and curve ball. The rate(%H) between height and stride length showed 68.42${\pm}$5.53(%H), 68.40${\pm}$5.45(%H) in the each pitching motion. 4. Pitching for curve ball showed longer stride length than pitching for straight ball that as the stride length was 140.35${\pm}$4.96cm and 144.8${\pm}$1.69cm. The rate(%H) between height and stride length showed 76.9${\pm}$3.77(%H), 79.39${\pm}$2.23(%H) in the each pitching motion. 5. Left knee joint angle did not show significant difference in the ST, LKU and HBP section in the each pitching motion. However, it was shown that knee joint angle was flexed much more in the LFC, MCP and BRP section in the pitching for curve ball. 6. Right shoulder joint angle did not show significant difference in the ST, LKU and HSP section. However, when pitches threw a curve ball in the LKU section. In the LFC section, the right shoulder joint angle was extended much more in the pitching for curve ball, and the angle was extended much in the MCP and BRP section in the pitching for curve ball than straight ball. 7. Right elbow joint angle did not show significant difference in the ST, LKU and HRP section in the two pitching motion. The angle had more flexion in the LFC and MCP section in the pitching for curve ball than the pitching for straight ball. The angle in the each pitching motion for straight ball and curve ball were extended by a narrow margin in the BRP section. 8. Right wrist joint angle was extended much more in the LFC and MCP section in the pitching for curve ball. In the BRP section, the angle was extended much more in the pitching for straight ball than curve ball.

• Journal of Electrical Engineering and Technology
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• v.11 no.6
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• pp.1535-1547
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• 2016

This paper proposes various design procedures for computing Power System Ancillary Service Requirement Assessment Indices (PSASRAI) for a Two-Area Thermal Reheat Interconnected Power System (TATRIPS) in a restructured environment. In an interconnected power system, a sudden load perturbation in any area causes the deviation of frequencies of all the areas and also in the tie-line powers. This has to be corrected to ensure the generation and distribution of electric power companies to ensure good quality. A simple Proportional and Integral (PI) controllers have wide usages in controlling the Load Frequency Control (LFC) problems. So the design of the PI controller gains for the restructured power system are obtained using Bacterial Foraging Optimization (BFO) algorithm. From the simulation results, the PSASRAI are calculated based on the settling time and peak over shoot concept of control input deviations of each area for different possible transactions. These Indices are useful for system operator to prepare the power system restoration plans. Moreover, the LFC loop coordinated with Redox Flow Batteries (RFB) has greatly improved the dynamic response and it reduces the control input requirements and to ensure improved PSASRAI, thereby improving the system reliability.