• Title/Summary/Keyword: demand control

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Development of ginseng powder using high hydrostatic pressure treatment combined with UV-TiO2 photocatalysis

  • Lee, Hyunah;Shahbaz, Hafiz Muhammad;Ha, Namho;Kim, Jeong Un;Lee, Sang Jun;Park, Jiyong
    • Journal of Ginseng Research
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    • v.44 no.1
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    • pp.154-160
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    • 2020
  • Background: Korean ginseng (Panax ginseng Meyer) powder is in rising demand because powder forms of foods are convenient to handle and are highly preservable. However, ginseng powder (GP) manufactured using the conventional process of air drying and dry milling suffers nutrient destruction and a lack of microbiological safety. The objective of this study was to prepare GP using a novel process comprised of UV-TiO2 photocatalysis (UVTP) as a prewashing step, wet grinding, high hydrostatic pressure (HHP), and freeze-drying treatments. Methods: The effects of UVTP and HHP treatments on the microbial population, ginsenoside concentration, and physiological characteristics of GP were evaluated. Results: When UVTP for 10 min and HHP at 600 MPa for 5 min were combined, initial 4.95 log CFU/g-fw counts of total aerobes in fresh ginseng were reduced to lower than the detection limit. The levels of 7 major ginsenosides in UVTP-HHP-treated GP were significantly higher than in untreated control samples. Stronger inhibitory effects against inflammatory mediator production and antioxidant activity were observed in UVTP-HHP-treated GP than in untreated samples. There were also no significant differences in CIELAB color values of UVTP-HHP-treated GP compared with untreated control samples. Conclusion: Combined processing of UVTP and HHP increased ginsenoside levels and enhanced the microbiological safety and physiological activity of GP.

ASSESSMENT AND CONTROL OF TOTAL NUTRIENT LOADS IN WATERSHED AND STREAM NETWORK IN SOUTH-WEST TEXAS

  • Lee, Ju-Young;Choi, Jae-Young
    • Water Engineering Research
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    • v.7 no.1
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    • pp.1-8
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    • 2006
  • Recently, the population growth and agricultural development are rapidly undergoing in the South-West Texas. The junction of three river basins such as Lavaca river basin, Colorado-Lavaca Coastal basin and Lavaca-Guadalupe Coastal basin, are interesting for non-point and point source pollutant modeling: Especially, the 2 basins are an intensively agricultural region (Colorado-Lavaca Coastal/Lavaca-Guadalupe Coastal basins) and several cities are rapidly extended. In case of the Lavaca river basin, there are many range land. Several habitat types wide-spread over three relatively larger basins and five wastewater discharge regions are located in there. There are different hazardous substances which have been released. Total nutrient loads are composed of land surface load and river load as Non-point source and discharge from wastewater facilities as point source. In 3 basins region, where point and non-point sources of poll Jtion may be a big concern, because increasing fertilizers and pesticides use and population cause. This project objective seeks to how to assess and control the accumulation of non-point and point source and discuss the main impacts of agriculture and environmental concern as non-point source with water quality related to pesticides, fertilizer, and nutrients and as point source with wasterwater discharge from cities. The GIS technique has been developed to aid in the point and non-point source analysis of impacts to natural resource within watershed. This project shows the losses in $kg/km^2/year$ of BOD (Biological Oxygen Demand), TN (Total Nitrogen) and TP (Total Phosphorus) in the runoff from the surface of 3 basins. In the next paper, sediment contamination will show how to evaluate in Estuarine habitats of these downstream.

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A Study on Smart Home Power-Control System with Power-Saving Green Adapter (전력절감 그린어뎁터를 이용한 스마트홈 전력 통제시스템)

  • Yoo, Seung-Jae;Park, Hee-Dong;Kim, Song-Gang
    • Convergence Security Journal
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    • v.13 no.4
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    • pp.85-92
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    • 2013
  • Today we have an obligation to pass the beautiful earth and enrich people's lives to next generations. According to the keynote, governments have a lot of resources to support the smart grid policies. Also the demand of the implementation of smart home applied the concept of smart grid is increasing rapidly. But the construction of smart home is centered on a new public housing except the pre-existing house which is counted for most of more than 90% of total. In this study, we suggest the implementation solution to make smart-homelike for the pre-existing houses without additional wiring or construction. We develop the technology reducing the unnecessary standby power 800mW to 20mW drastically. If we apply this technology, by the power off of main IC the actual power depends on the consumption of minimal devise located on the AC input side. Then the standby power becomes approximately 20mW(110ac).

Impact of Non-point Source Runoff on Water Resource Quality according to Water-Level Changes (수위 변화에 따른 비점오염의 상수원 수질 영향 분석)

  • Choi, Mi-Jin;Lee, Sang-Hyeon
    • Journal of Environmental Science International
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    • v.24 no.8
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    • pp.1045-1053
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    • 2015
  • This study evaluated the effect of water level of water resources on water quality in Ulsan. Two reservoirs, Sayeon Dam and Hoeya Dam, were selected and water quality of chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) were analyzed from 2012 to 2014. And the characteristics of precipitation were also analyzed for 70 years (1945~2014) because runoff of non-point pollutant was strongly affected by precipitation. As a result, water deterioration of Sayeon Dam and Hoeya Dam were affected in accordance with lowering water level. For example, the concentrations of COD and TN was negatively correlated with the water level when the water level of Sayeon Dam was gradually decreased in 2013. The TN concentration was increased to 1.432 mg/L from 0.875 mg/L while the lowest water level of Sayeon Dam was recorded 45 m in 2014. Additionally the concentration of COD and TN was sensitively increased with 0.213 mg/L/m and 0.058 mg/L/m on account of non-point pollutant runoff. It is indicated that hereafter a control of non-point pollutant runoff is the critical factors to maintain water resources because the contribution of non-point pollutant is expected to increase due to the frequent heavy rain events. Therefore, it is necessary to map out a specific plan for non-point pollutant control based on analyses of runoff characteristics, water pollution sources and reduction plans in water pollutants and to establish a water modelling and database system as a preventive action plan.

Cathodic Protection of Onshore Buried Pipelines Considering Economic Feasibility and Maintenance

  • Choi, Byoung-Yeol;Lee, Sang-Gil;Kim, Jin-Kwang;Oh, Jin-Soo
    • Journal of Advanced Research in Ocean Engineering
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    • v.2 no.4
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    • pp.158-168
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    • 2016
  • During the installation of crude oil or gas pipelines, which pass through onshore buried pipelines or onshore pipeline from subsea pipeline to onshore plant, countermeasures need to be implemented so as to ensure a sufficient design life by protecting the steel pipes against corrosion. This can be achieved through impressed current cathodic protection method for onshore pipelines and through galvanic sacrificial anode corrosion protection method for offshore pipelines. In particular, in the case of impressed current cathodic protection, isolation joint flanges should be used. However, this makes maintenance control difficult with its installation having a negative impact on price. Therefore, in this study, the most suitable methodology for onshore pipeline protection between galvanic sacrificial anode corrosion protection and impressed current cathodic protection method will be introduced. In oil and gas transportation facilities, the media can be carried to the end users via onshore buried and/or offshore pipeline. It is imperative for the field operators, pipeline engineers, and designers to be corrosion conscious as the pipelines would undergo material degradations due to corrosion. The mitigation can be achieved with the introduction of an impressed current cathodic protection method for onshore buried pipelines and a galvanic sacrificial anode corrosion protection method for offshore pipelines. In the case of impressed current cathodic protection, isolation joint flanges should be used to discontinuity. However, this makes maintenance control to be difficult when its installation has a negative impact on the price. In this study, the most suitable corrosion protection technique between galvanic sacrificial anode corrosion protection and impressed current cathodic protection is introduced for (economic life of) onshore buried pipeline.

OPF with Environmental Constraints with Multi Shunt Dynamic Controllers using Decomposed Parallel GA: Application to the Algerian Network

  • Mahdad, B.;Bouktir, T.;Srairi, K.
    • Journal of Electrical Engineering and Technology
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    • v.4 no.1
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    • pp.55-65
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    • 2009
  • Due to the rapid increase of electricity demand, consideration of environmental constraints in optimal power flow (OPF) problems is increasingly important. In Algeria, up to 90% of electricity is produced by thermal generators (vapor, gas). In order to keep the emission of gaseous pollutants like sulfur dioxide (SO2) and Nitrogen (NO2) under the admissible ecological limits, many conventional and global optimization methods have been proposed to study the trade-off relation between fuel cost and emissions. This paper presents an efficient decomposed Parallel GA to solve the multi-objective environmental/economic dispatch problem. At the decomposed stage the length of the original chromosome is reduced successively and adapted to the topology of the new partition. Two subproblems are proposed: the first subproblem is related to the active power planning to minimize the total fuel cost, and the second subproblem is a reactive power planning design based in practical rules to make fine corrections to the voltage deviation and reactive power violation using a specified number of shunt dynamic compensators named Static Var Compensators (SVC). To validate the robustness of the proposed approach, the algorithm proposed was tested on the Algerian 59-bus network test and compared with conventional methods and with global optimization methods (GA, FGA, and ACO). The results show that the approach proposed can converge to the near solution and obtain a competitive solution at a critical situation and within a reasonable time.

Operational Characteristics of the High-speed Interrupter for Reliability Enhancement of Power Supply and Demand (전력수급의 신뢰도 확보를 위한 고속 인터럽터 동작 특성)

  • Choi, Hye-Won;Choi, Hyo-Sang;Jung, Byung-Ik
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.1
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    • pp.143-148
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    • 2013
  • When the fault occurs in power system, the fault-current exceeds breaking capacity of the circuit breaker. So, reliablity of the power system is decreased sharply. Superconducting fault-current limiter (SFCL) is operated without impedance in normal state. The fault-current is limited by its impedance during the fault condition. However, the SFCL has several weak points such as huge size, high-price, liquid-nitrogen operation for the real power system. In this paper, We suggested the high-speed interrupter to limit the fault-current in case of the single line-to-ground fault. In addition, we compared the high-speed interrupter with the SFCL to ensure the operation reliability. The proposed interrupter detected the fault-current through the CT, and the power was supplied by operation of the SCR control system. In this experiment, the power of high-speed interrupter was applied after the 4.8[msec] from fault instant. The on-off operation of the interrupter was started after half-cycle from the fault. The fault-current was flowed into the impedance element by the switching operation of the high-speed interrupter. So, the fault current was limited within one cycle, and then it didnt exceed the capacity of a circuit breaker. We confirmed that there was slight difference between the SFCL with high-speed interrupter in terms of limiting-time of the fault-current and switching speed of the SCR. The high-speed interrupter was considered to be more efficient than the SFCL in size, cost or reliability.

Design of MAC Protocol to Guarantee QoS for Multimedia Traffic in a Slotted CDMA System (Slotted CDMA 환경에서 멀티미디어 트래픽의 QoS 보장을 위한 MAC 프로토콜)

  • 동정식;이형우;조충호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.8B
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    • pp.707-715
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    • 2003
  • In this paper, we propose a new MAC(Medium Access Control) protocol using Movable-boundary, which tries to guarantee Qos for multimedia traffic in the slotted CDMA system. In this scheme, the traffic scheduler assigns channel resource according to the packet priority per service class and adapts the Movable-boundary concept in which the minimum resource is assigned to each traffic class; the remaining resource if it is available can be assigned dynamically according to the temporal demand of other traffic classes. For performance analysis, we performed computer simulations to obtain throughput and packet loss rate and compared the results with Fixed-boundary system. We observed that the error rate of voice traffic could be maintained below a prescribed value while bursty traffic such as video source shares the same channel. In comparison with Fixed-boundary scheme, our protocol exhibits better throughput and packet loss rate performance.

A Study on Salt & Pepper Noise Removal using the Pixel Distribution of Local Mask (국부 마스크의 화소 분포를 이용한 Salt & Pepper 잡음 제거에 관한 연구)

  • Kwon, Se-Ik;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.9
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    • pp.2167-2172
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    • 2015
  • Due to the recent progress in information technology, demand for video imaging devices such as displays has grown. In general, images experience deterioration during the process of transmission due to various reasons. Many studies have boon undertaken on ways o reduce such noise. This paper6 suggests an algorithm that makes a judgment on the noise in order to remove the salt & pepper noise and replaces original pixels if they are non-noise while processing noise according to its density. The suggested algorithm shows a high PSNR of 30.49[dB] for Goldhill images that had been damaged of a high density salt & pepper noise(P = 60%), Compared to the exising CWMF, SWMF, and A-TMF, there were improvements by 17.74[dB], 11.52[dB], and 13.76[dB], respectively.

Image Restoration Algorithm Considering Pixel Distribution in AWGN Environments (AWGN 환경에서 화소 분포를 고려한 영상복원 알고리즘)

  • Kwon, Se-Ik;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.7
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    • pp.1687-1693
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    • 2015
  • Recently, demand for digital image processing devices increases rapidly, more clear images have been required. But, in the process of digital image acquisition, processing and transmission, image degradation occurs due to various external reasons and researches about noise reduction are on the rise. Therefore, this study suggested the algorithm to process AWGN(additive white Gaussian noise) by separately processing as three levels according to the pixel distribution in the mask in order to remove AWGN(additive white Gaussian noise) which is added in the image. Regarding the processed results by applying Barbara images which were damaged by AWGN(σ = 15), suggested algorithm showed the improvement by 2.87[dB], 2.95[dB], 2.88[dB], 1.52[dB], 1.49[dB], 1.58[dB] and 1.25[dB] respectively compared with the existing MF(5 × 5), A-TMF(5 × 5), AWMF(5 × 5), MF(3 × 3), A-TMF(3 × 3), AWMF(3 × 3), GF(5 × 5).