• Title/Summary/Keyword: control period

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Modeling of Multimedia Internet Transmission Rate Control Factors Using Neural Networks (멀티미디어 인터넷 전송을 위한 전송률 제어 요소의 신경회로망 모델링)

  • Chong Kil-to;Yoo Sung-Goo
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.4
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    • pp.385-391
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    • 2005
  • As the Internet real-time multimedia applications increases, the bandwidth available to TCP connections is oppressed by the UDP traffic, result in the performance of overall system is extremely deteriorated. Therefore, developing a new transmission protocol is necessary. The TCP-friendly algorithm is an example satisfying this necessity. The TCP-Friendly Rate Control (TFRC) is an UDP-based protocol that controls the transmission rate that is based on the available round trip time (RTT) and the packet loss rate (PLR). In the data transmission processing, transmission rate is determined based on the conditions of the previous transmission period. If the one-step ahead predicted values of the control factors are available, the performance will be improved significantly. This paper proposes a prediction model of transmission rate control factors that will be used in the transmission rate control, which improves the performance of the networks. The model developed through this research is predicting one-step ahead variables of RTT and PLR. A multiplayer perceptron neural network is used as the prediction model and Levenberg-Marquardt algorithm is used for the training. The values of RTT and PLR were collected using TFRC protocol in the real system. The obtained prediction model is validated using new data set and the results show that the obtained model predicts the factors accurately.

A Novel Control Algorithm of a Three-phase Four-wire PV Inverter with Imbalance Load Compensation Function

  • Le, Dinh-Vuong;Kim, Chang-Soon;Go, Byeong-Soo;Park, Minwon;Yu, In-Keun
    • Journal of Electrical Engineering and Technology
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    • v.13 no.3
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    • pp.1131-1137
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    • 2018
  • In this paper, the authors suggest a new control algorithm for a three-phase four-wire photovoltaic (PV) inverter with imbalance load compensation function using conventional proportional-integral (PI) controllers. The maximum power of PV panel is calculated by the MPPT control loop. The reference varying signals of current controllers are transformed to two different rotating frames where they become constant signals. Then simple PI controllers are applied to achieve zero steady-state error of the controllers. The proposed control algorithm are modeled and simulated with imbalance load configuration to verify its performance. The simulation results show that the maximum PV power is transferred to the grid and the imbalance power is compensated successfully by the proposed control algorithm. The inverter has a fast response (~4 cycles) during the transient period. The proposed control algorithm can be effectively utilized to the three-phase four-wire inverter with imbalance load compensation function.

Measurement of missing video frames in NPP control room monitoring system using Kalman filter

  • Mrityunjay Chaubey;Lalit Kumar Singh;Manjari Gupta
    • Nuclear Engineering and Technology
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    • v.55 no.1
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    • pp.37-44
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    • 2023
  • Using the Kalman filtering technique, we propose a novel method for estimating the missing video frames to monitor the activities inside the control room of a nuclear power plant (NPP). The purpose of this study is to reinforce the existing security and safety procedures in the control room of an NPP. The NPP control room serves as the nervous system of the plant, with instrumentation and control systems used to monitor and control critical plant parameters. Because the safety and security of the NPP control room are critical, it must be monitored closely by security cameras in order to assess and reduce the onset of any incidents and accidents that could adversely impact the safety of the NPP. However, for a variety of technical and administrative reasons, continuous monitoring may be interrupted. Because of the interruption, one or more frames of the video may be distorted or missing, making it difficult to identify the activity during this time period. This could endanger overall safety. The demonstrated Kalman filter model estimates the value of the missing frame pixel-by-pixel using information from the frame that occurred in the video sequence before it and the frame that will occur in the video sequence after it. The results of the experiment provide evidence of the effectiveness of the algorithm.

A Study on History of Criminal Policy in Korea (한국(韓國)의 형사정책(刑事政策)에 관한 역사적(歷事的) 고찰(考察))

  • Kim, Hyeong-Cheong
    • Korean Security Journal
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    • no.6
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    • pp.1-46
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    • 2003
  • During the ancient times, there was no separative judicial system and administrative , legislative and judiciary functions were ultimately concentrated in the all-powerful monarch. And the three states developed state organization , adopting hieratical structures and placing at the pinnacle . State Codes were promulgated to initiate a legal system to rule the people, these codes instituted under influence of China codes. The people tradition sees crime control as the preservation of the authority of hereditary rulers. In the period of the Koryeo dynasty, government accepted a serious of detailed penal code from Tang dynasty . Legal response to crime stressed preservation of the dynasty rather than making citizen behave according to certain rules. In the period of Early Joseon , the compilation of Grand Code for state administration was initiated, the Kyeongkuk Taejeon ,became comer stone of the dynastic administration and provided the monarchial system with a sort of constitutional law in written form. This national code was in portant means of criminal policy at that time, Late Joseon , the impact of Western culture entering through China gave further impetus to pragmatic studies which called for socio-economic reforms and readjustment. Approach to criminal justice policy emphasized more equitable operation of the criminal justice system ,rehabilitation and crime control. Korea-Japanese Treaty concluded on 22 August ,1910 and proclaim a week later ,Japan gave the coup de grace to the Korea Empire and changed the office of the Resident - General into the Government - General . Thus korean criminal policy were lost during a dark ages ,which lasted for 36 years after fall of Joseon Dynasty (the colnial period,1910${\sim}$1945). After 1945 Korea's liberation from Japanese colonial rule, the occupation of devided Korea by the United States and Soviet Union frustrated the efforts of Koreans to establish an independent government, and the transplantation of two conflicting political ideologies to south and the north of the 38th parallel further intensified the national split. U.S. military government office occupied the south of the 38 the parallel and placed emphasis on democracy of criminal policy. ln 1948, the U.S. military government handed over to the ROK government its administrative authority.

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Effects of dietary fermented spent coffee ground on nutrient digestibility and nitrogen utilization in sheep

  • Choi, Yongjun;Rim, Jong-su;Na, Youngjun;Lee, Sang Rak
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.3
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    • pp.363-368
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    • 2018
  • Objective: The objective of the study was to determine the effect of fermented spent coffee ground (FSCG) on nutrient digestibility and nitrogen utilization in sheep. Methods: Fermentation of spent coffee ground (SCG) was conducted using Lactobacillus plantrum. Fermentation was performed at moisture content of 70% and temperature of $39^{\circ}C$ with anaerobic air tension for 48 h. Four adult rams (initial body weight = $56.8{\pm}0.4kg$) were housed in a respiration-metabolism chamber and the treatments were: i) control (Basal diet; 0% SCG or FSCG), ii) 10% level of SCG, iii) 10% level of FSCG, and iv) 20% level of FSCG in $4{\times}4$ Latin square design. Each dietary experiment period lasted for 18-d with a 14-d of adaptation period and a 4-d of sample collection period. Results: In SCG fermentation experimental result, acid detergent insoluble nitrogen (ADIN) concentration of FSCG (64.5% of total N) was lower than that of non-fermented SCG (78.8% of total N). Digestibility of dry matter and organic matter was similar among treatment groups. Although crude protein (CP) digestibility of the control was greater than FSCG groups (p<0.05), the 10% FSCG group showed greater CP digestibility and nitrogen retention than non-fermented 10% SCG group (p<0.05). Body weight gain and average daily gain were linearly decreased with increasing FSCG feeding level (p<0.05). When the feeding level of FSCG was increased, water intake was linearly increased (p<0.05). With an increasing FSCG level, dry matter intake did not differ among groups, although the gain to feed ratio tended to decrease with increasing level of FSCG (p<0.10). Conclusion: Microbial fermentation of SCG can improve protein digestibility, thereby increasing CP digestibility and nitrogen utilization in sheep. Fermentation using microorganisms in feed ingredients with low digestibility could have a positive effect on improving the quality of raw feed.

Consideration of the Early Action in the GHG Emission Reduction (국내 온실가스 감축의 조기행동 인정 방안)

  • Song, Bo-Yun;Park, Su-Mi;Chung, Jin-Do
    • Journal of Korean Society for Atmospheric Environment
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    • v.27 no.2
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    • pp.209-213
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    • 2011
  • Enforcement Decree of the Framework Act on Low Carbon, Green Growth for achieving the country's GHG emission reduction goal of 30% was in effect. The remarkable content of the Act is the managements of targets for GHG reduction. So, the entities that have reduced voluntarily have much interest in the recognition of 'early action'. The recognition of early action is necessary to induce the fair competence of business entities and promote the voluntary GHG reduction. The definite and concrete guidance should be prepared. The important principles for this are the environmental integrity and the additionality. Based on this, the early action activities must be restricted to the voluntary, real, permanent, quantifiable, verifiable reduction. In the early action recognition, its credit should be allocated additionally set aside from the GHG target allocation in the national total allowance. Through this, the reward for the early reduction should be realized on market mechanism. The effective period to award the early action should be addressed. This can be the period after the enactment of framework on GHG reduction in effect and before the beginning year of GHG target control. It should be set with flexibility through the collection and consultation of the sector's opinions. The appropriate allowance reserve of early action was estimated as approximately 1~1.5% by using the data from the 'Pilot GHG Emission Trading Program' operated by Ministry of Environment. Also, the concrete and detail guidance to construct the necessary infra which is used to register the related information of early action activities should be prepared.

Application Load Duration Curve for Evaluation of Impaired Watershed at TMDL Unit Watershed in Korea (수질오염총량 단위유역의 유량조건별 수체 손상 평가를 위한 부하지속곡선 적용성 연구)

  • Hwang, Ha-Sun;Yoon, Chun-Gyeong;Kim, Ji-Tae
    • Journal of Korean Society on Water Environment
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    • v.26 no.6
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    • pp.903-909
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    • 2010
  • The purpose of this study was evaluated on the applicability of Load Duration Curve Method (LDC Method) using HSPF watershed model and sampling data for efficient TMDLs in Korea. The LDC Method was used for assessment pollutant characteristics in watershed and water quality variation in each water flow level. Load Duration Curve is applied for judge the level of impaired water-body and can be estimated the impaired level by pollutant, such as BOD, T-N, and T-P in this study depending on variation of stream flow. As a result, BOD, T-P was usually exceed the standard value at low flow and dry hydrologic period. Improvement of effluent concentration from WWTP and riparian buffer protection zone are effective to improve the water quality. T-N showed the worst condition at mid-range hydrologic period and moist hydrologic period. Therefore, soil erosion control program and BMPs for non-point source pollution control is effective for recovery the water quality, which can be useful method for management of water quality in the plan of recovery water quality spontaneously. Applicability of LDC Method was evaluated in the Nakbon A watershed. However, we need to consider more detailed and accumulated data set such as accurate GIS data and detail pollution data, and WWTP discharge water quality data for accurate evaluation of watershed. Overall, The LDC Method is adequate for evaluation of watersheds characteristics, and its application is recommended for watershed management and TMDL Implementation.

An efficient channel assignment meghod for real-time service in the IEEE 802.11 wireless LAN system (IEEE 802.11 무선 LAN 환경에서 실시간 서비스를 제공하기 위한 채널 구간 할당 방안)

  • 박중신;류시훈;강태원;이준호;이재용;이상배
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.23 no.5
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    • pp.1249-1259
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    • 1998
  • This paper proposes an efficient channel assignment method for real-time service in the IEEE 802.11 Wireless LAN system, and analyzes the supportability to real-time service and the channel utilzation of that through computer simulations. The improved MAC(Medium Access Control) protocol employing the proposed channel assignment method achieved good throughput over contention period as well as contention-free period by making real-time terminals transmit the information about their desiring value before starts of data transmissions. For performance evaluation of the proposed method, a simulation analyzing the variation of allocated bandwidths to terminals using real-time service and their buffer sizes wasexecuted. Real-time data traffics was modeled s 7-stae transition VBR sources, and asynchronous data traffics modeled as Poisson processes. In the simulation, the proposed method showed smaller variation of the bandwidth of each terminal and samller buffer size than the existing method, and also recorded good throughput over contention period.

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Effect of Protective Compounds on the Survival, Electrolyte Leakage, and Lipid Degradation of Freeze-Dried Weissella paramesenteroides LC11 During Storage

  • Yao, Amenan A.;Wathelet, Bernard;Thonart, Philippe
    • Journal of Microbiology and Biotechnology
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    • v.19 no.8
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    • pp.810-817
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    • 2009
  • The effect of cryoprotectants (maltodextrin+glycerol) and cryoprotectants+antioxidant [ascorbic acid and/or butylated hydroxytoluene (BHT)] mixtures on the survival, electrolyte leakage, and lipid degradation of freeze-dried Weissella paramesenteroides LC11 during storage was investigated and compared with that of the control (cells without additives) over a 90-day storage period at 4 or $20^{\circ}C$ in glass tubes with water activity ($a_w$) of 0.23. The survival, electrolyte leakage, and lipid degradation were evaluated through colony counts, electrical conductivity, and thiobarbituric acid reactive substances (TBARS) content, respectively. The fatty acids composition was determined by gas chromatography, in both the total lipid extract and the polar lipid fraction, and compared with that of the control after the 90-day storage period. As the storage proceeded, increases in leakage value and TBARS content, as well as a decrease in viability, were observed. After 90 days of storage, the major fatty acids found in both the total lipid extract and the polar lipid fraction were palmitic (16:0), palmitoleic (16:1), stearic (18:0), oleic (18:1), linoleic (18:2), and linolenic (18:3) acids. The survival, leakage value, TBARS content and 18:2/16:0 or 18:3/16:0 ratio were the greatest for the protected strain held at $4^{\circ}C$. Cells with the cryoprotectants+BHT mixture showed the highest percentage of survival and 18:2/16:0 or 18:3/16:0 ratio in both lipid extracts, as well as the lowest leakage value and TBARS content after the 90-day storage period. Drying cells with the cryoprotectants+BHT mixture considerably slowed down polar lipid degradation and loss of membrane integrity, resulting in improved viability during storage.

Browning Prevention of Black Carrot Extract and the Quality Characteristics of Jelly Supplemented with Black Carrot Extract (자색 당근즙의 갈변 방지와 자색 당근즙 첨가 젤리의 품질 특성)

  • Nho, Hyun-Jung;Jang, Soo-Yeon;Park, Jae Jung;Yun, Ho Sik;Park, Sunmin
    • Journal of the Korean Society of Food Culture
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    • v.28 no.3
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    • pp.293-302
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    • 2013
  • We investigated treatments for the browning prevention of black carrot extracts and determined the characteristics and qualities of jelly supplemented with black carrot extract. Ascorbic acid, citric acid, and NaCl were added to black carrot extract and changes in color, texture, and anthocyanin content were evaluated. Changes were also determined and a sensory evaluation was performed for jelly supplemented with black carrot extract. The addition of 0.15 and 0.20% ascorbic acid prevented the browning of black carrot extracts and decreased anthocyanin content during the storage period. However, citric acid did not have a preventative effect, despite decreasing the pH below 5.0. Similar to results on the extract, 0.15% ascorbic acid maintained a reddish-violet color in jelly supplemented with black carrot extract by lowering browning during the storage period. Jelly supplemented with 0.15% ascorbic acid had an increased elasticity, gumminess, and chewiness, but jelly supplemented with 0.15% ascorbic acid+0.05% NaCl had a lowered hardness compared with the control during the storage period. In a sensory evaluation, the overall preference, in descending order, was: 0.15% ascorbic acid+0.05% NaCl > 0.15% ascorbic acid > control. In conclusion, 0.15~0.20% ascorbic acid prevented the browning of black carrot extract and inhibited a decrease in anthocyanin content. Jelly supplemented with black carrot extract and 0.15% ascorbic acid+0.05% NaCl were optimal for producing a soft jelly texture.