• Title/Summary/Keyword: PLC

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Digital Asset Analysis Methodology against Cyber Threat to Instrumentation and Control System in Nuclear Power Plants (원자력발전소의 디지털계측제어시스템의 사이버보안을 위한 디지털 자산분석 방법)

  • Koo, In-Soo;Kim, Kwan-Woong;Hong, Seok-Boong;Park, Geun-Ok;Park, Jae-Yoon
    • The Journal of the Korea institute of electronic communication sciences
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    • v.6 no.6
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    • pp.839-847
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    • 2011
  • Instrumentation & Control(I&C) System in NPP(Nuclear Power Plant) plays a important role as the brain of human being, it performs protecting, controling and monitoring safety operation of NPP. Recently, the I&C system is digitalized as digital technology such as PLC, DSP, FPGA. The different aspect of digital system which use digital communication to analog system is that it has potential vulnerability to cyber threat in nature. Possibility that digital I&C system is defected by cyber attack is increasing day by day. The result of cyber attack can be adverse effect to safety function in NPP. Therefore, I&C system required cyber security counter-measures that protect themselves from cyber threat efficiently and also cyber security design should be taken into consideration at concept stage in I&C system development process. In this study, we proposed the digital asset analysis method for cyber security assessment of I&C system design in NPP and we performed digital asset analysis of I&C system by using the proposed method.

The Design and Implementation of AMI System Using Binary CDMA (Binary CDMA 기반의 AMI 시스템 설계 및 구현)

  • Joe, In-Whee;Jeong, Jong-Yuel
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.8C
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    • pp.663-669
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    • 2012
  • To solve the energy problem and finding new growth engines, interest for the smart grid is increasing and related technologies are making great efforts to secure in the world. AMI (Advanced Metering Infrastructure) Among them is the first to be constructed and getting attention as a key component of smart grid. A fusion of various technologies in technology development and demonstration is underway on Jeju Island Smart Grid Demonstration Complex in Korea, and focusing on broadband power line communication technology infrastructure is actively underway in Korea Electric Power Corporation. AMI system using power line communication technology without building a separate communication lines are available for power supply lines, but communication is impossible in occurs because admission to the power company or the ideal infrastructure for communication is not considered. In this paper, we analyze the requirements to build AMI system using Binary CDMA and powerline communications technology, and design the basic communication protocol based on Binary CDMA, implement network management and relay feature. By doing so, ways to apply Ad-hoc Binary CDMA indigenous technology to the AMI system were derived, and could build a system to make use of Wired (PLC) and wireless (Binary CDMA) simultaneously.

A study for Menu Life Cycle of Hotel Restaurants (호텔레스토랑의 메뉴수명주기 (Menu Life Cycle)에 관한 연구)

  • 송청락
    • Culinary science and hospitality research
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    • v.2
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    • pp.59-87
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    • 1996
  • This study has been done by giving the guide when development of menu or doing marketing strategy in Hotel Restaurant. All products and service has a regular course from induction in market to disappear, so it shall be come out Products Life Cycle theory. In eating business, under the tendency and existing cycle to change menu by taste of customers, liking variation, change of periodic status (environment), MLC(Menu Life Cycle) shall be advised by application PLC(Products Life Cycle) in the process of induction of some menu first and spreading the same business field and then deletion (disappearance) from menu because of no popular. In Emergence Stage, it shall be tried to inform new menu through Cooking Contest, presentation of new menu, free sampling party and others. In Growth Stage, it shall be changed package menu or set menu. In Maturity Stage, it shall be provided complimentary ticket, gift coupon or discount for the customers with some degree of selling record in order to increase using frequency and selling amount after insure new customers. In Decline Stage, it shall be groped for entry underdeveloped country or less advance nation, but there is no possibility to devote in enterprise, it shall be planned substitute menu development in order to withdraw. By inducting MLC concept, it shall be provided the available informations such as“how could some menu be circulate in some restaurant”“Accordingly do strengthen promotion activities or go to low developed area or overseas, or delete it from menuitems and so on”. In the time of decline some menu, it is judged to the time of plan(preparation) of new menu development. In the broad view, when consideration of the concept of menu life cycle, it shall be possible to know which menu is decayed and which menu is developed newly or grown-up, so it shall be provided the important information to estimate the tendency of changing menu and set-up a menu development plan.

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Performance Comparison over Gaussian Channel of Binary Chirp DS-CDMA System for Powerline Communication (전력선 통신을 위한 Binary Chirp DS-CDMA System의 가우시안 채널 하에서 성능 비교)

  • Park, Sung-Wook;Park, Jong-Wook
    • 전자공학회논문지 IE
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    • v.43 no.2
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    • pp.70-74
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    • 2006
  • The performance of conventional direct sequence code division multiple access (DS-CDMA) systems is decreased under environments such as additive white Gaussian noise (AWGN), channel distortion and interference noise due to multiple access user. By means of this parameter, auto correlation value of pseudo noise spreading sequence is decreased at receiver. This techniques which are based on correlation of between signature waveform signal. In this paper, to improve correlation property, we proposed the binary chirp DS-CDMA techniques which combine the DS-CDMA and chirp modulation. The proposed system which is based on binary chirp symbol has a good correlation value. Thus, we called BC DS-CDMA. To evaluate the system's performance, we compare the performance of the proposed systems with DS-CDMA systems under AWGN channel and halogen noise which exists on the powerline. The simulation results show that the proposed method has better performance than conventional technique.

Sorting and Function of the Human Folate Receptor Is Independent of the Caveolin Expression in Fisher Rat Thyroid Epithelial Cells

  • Kim, Chong-Ho;Park, Young-Soon;Chung, Koong-Nah;Elwood, Patrick C.
    • BMB Reports
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    • v.35 no.4
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    • pp.395-402
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    • 2002
  • Caveolae are small, flask-shaped, non-clathrin coated invaginations of the plasma membrane of many mammalian cells. Caveolae have a coat that includes caveolin. They have been implicated in numerous cellular processes, including potocytosis. Since the human folate receptor (hFR) and other glycosyl-phosphatidylinositol (GPI)-tailed proteins have been co-localized to caveolae, we studied the caveolin role in the hFR function by transfecting hFR and/or caveolin cDNA into Fischer rat thyroid epithelial (FRT) cells that normally do not express detectable levels of either protein. We isolated and characterized stable clones as follows: they express (1) high levels of caveolin alone, (2) hFR and caveolin, or (3) hFR alone. We discovered that hFR is correctly processed, sorted, and anchored by a GPI tail to the plasma membrane in FRT cells. No difference in the total folic acid binding or cell surface folic acid binding activity were found between the FRT cells that were transfected with hFR, or cells that were transfected with hFR and caveolin. The hFR that was expressed on the cell surface of clones that were transfected with hFR was also sensitive to phosphatidylinositol-specific phospholipase C (PI-PLC) release, and incorporated radiolabeled ethanolamine that supports the attachment of a GPI-tail on hFR. We conclude that the processing, sorting, and function of hFR is independent on the caveolin expression in FRT cells.

Characteristics of Purinergic Receptor Expressed in 3T3-L1 Preadipocytes

  • Lee, Hyung-Joo;Baik, Joon-Heum;Kim, Min-Jeong;Kim, Na-Hyun;Kong, In-Deok
    • Biomedical Science Letters
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    • v.15 no.4
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    • pp.319-326
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    • 2009
  • Extracellular ATP elicits diverse physiological effects by binding to the G-protein-coupled P2Y receptors on the plasma membrane. In addition to the short-term effects of extracellular nucleotides on cell functions, there is evidence that such purinergic signalling can have long-term effects on cell proliferation, differentiation and death. The 3T3-L1 cell line derived from mouse embryo is a well-established and commonly utilized in vitro model for adipocytes differentiation and function. However, the distributions and roles of P2Y subtypes are still unknown in the preadipocyte. In this study, we identified the distributions and roles of P2Y subtypes in preadipocyte using $Ca^{2+}$ imaging and realtime PCR. ATP increased the $[Ca^{2+}]_i$ in a concentration-dependent manner. ATP increased $Ca^{2+}$ in absence and/or presence of extracellular $Ca^{2+}$. Suramin, non-selective P2Y blocker, largely blocked the ATP-induced $Ca^{2+}$ response. U73122, a PLC inhibitor, completely inhibited $Ca^{2+}$ mobilization in 3T3-L1 cells. The mRNA expression by realtime PCR of P2Y subtypes was $P2Y_2:P2Y_5:P2Y_6=1.0:12.5:0.3$. In conclusion, we showed that $P2Y_5$ receptor is a dominant purinergic receptor in preadipocytes, and multiple P2Y receptors could involve in differentiation and migration via regulating of intracellular calcium concentration.

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Characterization of Matrix Metalloproteinase Expression in Triglyceride Treated THP-1 Macrophages

  • Cho, Yoonjung;Lim, Jaewon;Lee, Dong Hyun;Jung, Byung Chul;Lee, Min Ho;Jung, Dongju;Kim, Yoon Suk;Kim, Tae Ue;Rhee, Ki-Jong
    • Biomedical Science Letters
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    • v.19 no.1
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    • pp.9-16
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    • 2013
  • Elevated blood triglyceride (TG) levels correlate with development of atherosclerosis suggesting that TG may promote the development of this disease. During atherosclerosis, TG is taken up by tissue macrophages which result in dramatic changes in various secreted factors. One such factor is the family of matrix metalloproteases (MMP) which are involved in tissue remodeling during both physiological and pathological processes. In this study, we examined the MMP expression profile in PMA-differentiated THP-1 macrophages treated with TG. We found that TG-treated THP-1 macrophages showed decreased expression of MMP-3, MMP-7, MMP-8 and MMP-9 in a time- and dose-dependent manner. In contrast, expression of MMP-1, MMP-2, and MMP-10 remained relatively unchanged after TG treatment. In addition, we found that expression of select MMPs was affected by various inhibitors of signaling pathways. In particular, expression of MMP-3 was slightly recovered by cRAF and PLC signaling pathway inhibitors. These data suggests a possible role of MMPs in macrophages during TG-induced atherosclerosis.

Development of CNC controller based on i80486 and 32bit DSP chip (i80486과 32비트 DSP를 사용한 CNC 제어기의 개발)

  • Kim, Dong-Il;Song, Jin-Il;Kim, Sung-Kwan;Lee, Choong-Hwan;Lee, Yun-Suk;Kang, Moon;Na, Sang-Keun;Lim, Yong-Gyu;Nam, Ki-Jun
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10a
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    • pp.537-540
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    • 1992
  • This paper presents Samsung CNC (Computer Numerical Controller) system with an intel 80486/487 as the main CPU and a 32 bit floating point DSP(Digital Signal Processor) TMS320C30 as the motion control CPU. The Samsung CNC system diverse user-frienly characteristics such as multi-tasking, powerful menu system, internal PLC system, and 2/3 dimensional graphics in wire and solid mode. The main CPU executes central processing program, user interface program, interpreter, BMI, etc while the motion control CPU carries out some interpolations, acceleration/deceleration, and PID control algorithm with feedforward terms. Complex interpolations except linear and circular ones are performed on the main control CPU. The experimental results for the circular interpolation under linear acceleration/deceleration shows that the proposed CNC system can be widely used in controlling machining centers with good machining accuracy.

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Fagopyrum esculentum Extract Suppresses the Release of Inflammatory Mediator and Proximal Signal Events in $Fc{\varepsilon}RI$-mediated RBL-2H3 Cell Activation (교맥(蕎麥)의 비만세포 염증매개물질의 분비와 $Fc{\varepsilon}RI$ 신호전달에 미치는 효과)

  • Kang, Kyung-Hwa
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.26 no.4
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    • pp.469-474
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    • 2012
  • Fagopyrum esculentum(FE) is an important food crop and medicinal plant that is used to improve diabetes, obesity, hypertension, hypercholesterolemia and constipation in Korea, but the underlying mechanisms involved in its anti-allergic activity are not fully understood. We investigated the effects on the release of inflammatory mediator and proximal signal events in $Fc{\varepsilon}RI$-mediated RBL-2H3 cell activation. FE reduced antigen (DNP-HSA)-induced release of histamine, prostaglandin D2 (PGD2) and cysteinyl Leukotriene (cysLT) in IgE-sensitized RBL-2H3 cells. In addition, it inhibited antigen-induced HDC2 and COX-2 and 5-LO mRNA expression in IgE-sensitized RBL-2H3 cells. FE also suppressed antigen-induced $Fc{\varepsilon}RI{\beta}$ and $Fc{\varepsilon}RI{\gamma}$ subunit mRNA expression in these cells. To identify the mechanisms underpinning the inhibition of release of inflammatory mediators such as histamine and PGD2 and cysLT by FE, we examined the proximal signal events of intracellular FceRI signaling molecules. FE suppressed antigen-induced phosphorylation of Lyn, Syk, LAT, $PLC{\gamma}1$, PI3K, Akt and cPLA2. Collectively, the anti-allergic effects of FE in vitro suggest its possible therapeutic application to inflammatory allergic diseases, in which its inhibition of inflammatory mediator and FceRI-dependent signaling events in mast cells may be hugely beneficial.

Effect of Diesel Exhaust Particles (DEP) on the Activity of Phospholipase D (PLD) in RAW 264.7 Cells

  • Nam Hae-Yun;Shin Hyun-Yong;Ahn Eun-Kyung;Kim Hyung-Jung;Lim Young
    • Toxicological Research
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    • v.22 no.1
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    • pp.9-13
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    • 2006
  • Diesel exhausted particles (DEP), a kind of fine particles with aerodynamic diameters less than $2.5{\mu}m$ (PM2.5), is of great concern to human health because they remain in atmosphere for long periods, invade an indoor air environment, and can be breathed most deeply into lung and reached the alveoli because of their small size ($0.1{\sim}0.4\;{\mu}m$ in diameter). Epidemiological and experimental studies suggested that DEP may play an active role in the increased respiratory mortality and morbidity. In addition to their physical characteristics, the chemical components including polyaromatic hydrocarbon (PAH) are regarded as a carcinogen causing pulmonary tumors. PLD plays an important role in cell proliferation with various physiological phenomena and affects other enzymes by activating signal transduction pathway. We investigated the cytotoxic mechanism of DEP on RAW 264.7 cells focusing on the role in activation of PLD. Our results suggested DEP induced PLD activity through a specific signaling pathway involving phospholipase $A_2$, PLC, PKC and $Ca^{2+}$ mobilization.