• Title/Summary/Keyword: SFC

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Improvement of Memory Efficiency for Alternative Sequence in Process Control System Described by SFC (SFC로 설계된 공정제어에서 선택시퀀스의 메모리효율향상)

  • You, Jeong-Bong
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.5
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    • pp.55-61
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    • 2010
  • When we design the control system used Programmable Logic Controller(PLC) by Sequential Function Chart(SFC), if we use a SFC, it is easy to know the sequential flow of control, to maintenance the controller and to describe a program. We program a SFC by a unique sequence, an alternative sequence and a parallel sequence. If we program a SFC by a alternative sequence, the memory size of a alternative sequence must be larger than the memory size of a unique sequence. Therefore this thesis show an efficient method to reduce a memory size and we confirmed its feasibility through actual example.

Study on the Time Improvement of Interrupt Program by SFC (SFC언어에서 인터럽트 프로그램 시간개선에 관한 연구)

  • You, Jeong-Bong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.10
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    • pp.5134-5139
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    • 2013
  • Ladder Diagram(LD) or Sequential Function Chart(SFC) is used for the design of complex modern control system with Programmable logic controller(PLC). LD is the most widely utilized among PLC standard language. But recently, SFC is used frequently. SFC is very easy to grasp the sequential flow of control logic but is difficult for describing combinational logic. When the interrupt factor is occurred, the main program is stopped. And after the interrupt program is completed, the main program is restart. Therefore the more complex the interrupt program, the main program is interrupted downtime will be that much longer. In this paper, we propose the method for interrupt implementation without the dwell time of the main program by SFC language and confirm his feasibility through the simulation.

An Efficient Function of Self Test in PLC Control Designed by SFC (SFC로 설계된 PLC 제어에서 효율적인 자기진단 기능)

  • You, Jeong-Bong
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.4
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    • pp.153-158
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    • 2008
  • When we design the control system used Programmable Logic Controller(PLC), we program the main algorithm by Ladder Diagram(LD) in many standard language. But if we use an Sequential Function Chart(SFC), we is easy to know the sequential flow of control, to maintenance the controller and to describe a program. Even though a SFC have many merits, A SFC have some problems like a condition and a function of self test. Therefore this thesis show an efficient function of self test and we confirmed its feasibility through actual example.

Growth of Lettuce and Young Radish and Changes of Soil Chemical Properties after Application of Soldier Fly Compost (동애등에분 처리 시 상추와 무의 생육 및 토양화학성 변화)

  • Young-Sun Kim;Geung-Joo Lee
    • Korean Journal of Environmental Agriculture
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    • v.42 no.2
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    • pp.152-158
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    • 2023
  • This study was conducted to evaluate the effects on soil chemical properties and plant growth after applying soldier fly compost (SFC). Treatments were as follows. No fertilizer (NF), control, SFC1 (SFC 250 kg/10a), SFC2 (SFC 500 kg/10a) and SFC3 (SFC 1,000 kg/10a). As compared to control in the pot test, organic matter (OM) and exchangeable sodium (Ex-Na) of SFC3 treatment were increased, and growth and nutrient uptake of young radish were not significantly different. Correlation coefficient between soil chemical factors like total nitrogen (T-N), OM, and CEC and uptake of nitrogen (N) and phosphorus (P) was significantly positive (p≤0.05). Compared to control in the field test, electrical conductivity, T-N, OM, Av.-P2O5, and CEC was increased, and lettuce growth was not significantly different. Correlation coefficient between application amount of SFC and T-N, OM, and Av.-P2O5 was significant positively (p≤0.05). These results indicated that the application of SFC improved nutrient availability of soil by increasing OM and CEC.

Effects of Soil Amendment Blended with Soldier Fly Casts and Coco Peat on Physicochemical Properties of Sand Soil (동애등에분변토와 코코피트가 혼합된 토양개량제가 모래의 이화학성에 미치는 영향)

  • Kim, Young-Sun;Lee, Sang-Beom;Ham, Suon-Kyu;Lim, Hye-Jung;Choi, Young-Cheol;Park, Kwan-Ho
    • Weed & Turfgrass Science
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    • v.3 no.2
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    • pp.143-149
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    • 2014
  • This study was conducted to evaluate the effects of the mixture ratio of soil amendments blended with coco peat (Coco) and American soldier fly cast (SFC) on the physicochemical properties on the sand green. pH and EC of soil were significantly related to mixture ratio of SFC, Mix1, Mix2 and Mix3. Capillary porosity, air-capillary porosity and total porosity of root zone mixed SFC, Coco, Mix1, Mix2 and Mix3 were met to the USGA green specification. The mixture ratios of Mix1 and Mix2 in root zone were positively related capillary porosity and total porosity, and air-capillary porosity was negatively related capillary porosity and hydraulic conductivity. Capillary porosity of Mix1, Mix2 and Mix3 blended SFC and Coco was affected by SFC and Coco, and total porosity by Coco. These results showed that soil amendments blended SFC and Coco was developed capillary porosity and hydraulic conductivity on the USGA sand green than these of SFC.

Service Function Chaining Architecture for Distributed 5G Mobile Core Networks (분산 모바일 코어기반 5G 네트워크에서의 Service Function Chaining 적용구조)

  • Sun, Kyoungjae;Kim, Younghan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.12
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    • pp.1914-1924
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    • 2016
  • In this paper, considering virtualized Evolved Packet Core(vEPC) network for 5G mobile network, we propose architecture for supporting Service Function Chaining(SFC) in 5G mobile network. Using SFC in 5G network, dynamic path configuration and providing network services based on subscriber and traffic information. SFC technology provides logical ordered set of network functions and delivers packet through providing logical path over the physical network. Based on the perspective of 5G core network in distributed manner, we design hierarchical SFC architecture to manage SFC for global path including vEPC and SGi-LAN network, and internal path between virtualized network functions in each cloud. In this paper, we define architecture and call flow for establishing data path using SFC. Finally, we design testbed architecture for real implementation based on open source software.

Monitoring as a Service (MaaS) for scalable SFC provisioning (확장 가능한 SFC 프로비저닝을 위한 Monitoring as a Service (MaaS))

  • Lee, Jisoo;Yeom, Sanggil;Choo, Hyunseung
    • Proceedings of the Korea Information Processing Society Conference
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    • 2018.05a
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    • pp.65-68
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    • 2018
  • 오늘날 네트워크 서비스에 대한 수요가 증가함에 따라 네트워크 트래픽 또한 증가하고 있다. 이는 네트워크 서비스 구성을 복잡하게 만들어 최종 사용자에게 전달되는 네트워크 기능의 동적 구성이 요구된다. Service Function Chaining (SFC)은 일련의 Service Function (SF) 세트로 구성된 새로운 네트워크 서비스 배포 모델이다. SFC는 특정 서비스에 따라 플로우를 분류하여 네트워크 운영자의 효율적인 서비스 제공을 보장한다. SFC의 성능은 SFC를 구성하는 SF Instance (SFI)와 상관 관계를 가진다. 이때 다수의 SFC 환경에서 단일의 SFI 사용 시, 트래픽 오버플로우가 발생할 수 있다. 따라서, 본 논문에서는 확장 가능한 SFC 프로비저닝을 위한 Monitoring as a Service (MaaS)를 제안한다.

A Study on Starting Algorithm of Large Synchronous Motor for Gas Turbine in Field-Weakening Region using SFC (SFC를 이용한 약계자 영역에서 가스터빈용 동기 전동기의 기동 알고리즘에 관한 연구)

  • Ryu, Ho-Seon;Lee, Joo-Hyun;Kang, Youn-Jong;Hwang, Seon-Hwan;Kim, Jang-Mok
    • The Transactions of the Korean Institute of Power Electronics
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    • v.13 no.6
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    • pp.411-419
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    • 2008
  • SFC(Static Frequence Converter)system has come to be used as start up drive system for large synchronous motor in many industry applications. Many papers have been presented the control algorithm for pumped storage power generation using SFC system but they did not included about start up algorithm of SFC system for gas turbine. This paper presents the field weakening control algorithm for a large synchronous motor using output signal of anti-windup in PI current regulator and the results of experiment show that the proposed algorithm is proper and effective.

Effect of Soldier Fly Casts Mixed Soil on Change of Soil Properties in Root Zone and Growth of Zoysiagrass (동애등에 분변토의 혼합 상토가 한국잔디의 생육 및 근권 토양에 미치는 영향)

  • Lee, Sang-Beom;Kim, Young-Sun;Ham, Suon-Kyu;Lim, Hye-Jung;Choi, Young-Cheol;Park, Kwan-Ho
    • Weed & Turfgrass Science
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    • v.2 no.3
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    • pp.298-305
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    • 2013
  • Soldier fly casts produced by eco-friendly treatment of food waste with American soldier fly was composting cast mixed food waste compost and soldier fly pupa. This study was conducted to evaluate a possibility of soldier fly casts (SFC) as soil amendment by investigating soil properties and zoysiagrass growth. Amendments were selected coco peat, compost and SFC and their ratio mixed with sand were non-amendment (NA), 7% coco peat(Coco), 7% compost (Comp), 3.5% SFC (1/2SFC) and 7% SFC. In soil properties, SFC was increased CEC than NA and T-N, Av-$P_2O_5$ and exchangeable K in soil than Coco. Compared with Coco and Comp, turf quality such as turf color index and chlorophyll index in SFC was higher and root length of zoysiagrass longer. Growth of shoot, runner and root in SFC was increase than that of Coco and Comp. These results indicated that 7% SFC applied as soil amendment was improved growth and quality of zoysiagrass by prompting soil productivity and nutrient availability in soil and root growth.

Study on the Composition of Subsystem Designed by Hierarchical Control Structure of SFC (SFC의 계층제어구조로 설계된 서브시스템 결합에 관한 연구)

  • You, Jeong-Bong
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.20 no.4
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    • pp.49-55
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    • 2006
  • In industrial control system used by Programmable Logic Controller(PLC), ladder Diagram(LD) is the must widely utilized and plays an important role in industrial control system. But recently, the study about Sequential Function Chart(SFC) is performed actively. When we program by SFC, generally, we design one routine from start to end. This method is difficult to design, and we often make mistakes. In this paper, we propose the method that we compose each sub-system after we design each sub-system and confirm his feasibility through an actual examples.