• Title/Summary/Keyword: BlockChain

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Design of 250-Mbps 10-Channel CMOS Optical Receiver Away for Parallel Optical Interconnection (병렬 광 신호 전송을 위한 250-Mbps 10-채널 CMOS 광 수신기 어레이의 설계)

  • Kim, Gwang-O;Choe, Jeong-Yeol;No, Seong-Won;Im, Jin-Eop;Choe, Jung-Ho
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.37 no.6
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    • pp.25-34
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    • 2000
  • This paper describes design of a 250-Mbps 10-channel optical receiver array for parallel optical interconnection with the general-purpose CMOS technology The optical receiver is one of the most important building blocks to determine performance of the parallel optical interconnection system. The chip in CMOS technology makes it possible to implement the cost-effective system also. Each data channel consists of analog front-end including the integrated photo-detector and amplifier chain, digital block with D-FF and off-chip driver. In addition, the chip includes PLL (Phase-Lock Loop) for synchronous data recovery. The chip was fabricated in a 0.65-${\mu}{\textrm}{m}$ 2-poly, 2-metal CMOS technology. Power dissipation of each channel is 330㎽ for $\pm$2.5V supply.

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A Study on Zone-based Intrusion Detection in Wireless Network Environments (무선 네트워크 환경에서 영역기반 침입탐지 기법에 관한 연구)

  • Yang, Hwanseok
    • Convergence Security Journal
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    • v.19 no.5
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    • pp.19-24
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    • 2019
  • It is impossible to apply the routing protocol in the wired environment because MANET consists of only mobile nodes. Therefore, routing protocols considered these characteristics are required. In particular, if malicious nodes are not excluded in the routing phase, network performance will be greatly reduced. In this paper, we propose intrusion detection technique based on region to improve routing performance. In the proposed technique, the whole network is divided into certain areas, and then attack detection within the area using area management node is performed. It is a proposed method that can detect attack nodes in the path through cooperation with each other by using completion message received from member nodes. It also applied a method that all nodes participating in the network can share the attack node information by storing the detected attack node and sharing. The performance evaluation of the proposed technique was compared with the existing security routing techniques through the experiments and the superior performance of the proposed technique was confirmed.

A New Low Power LFSR Architecture using a Transition Monitoring Window (천이 감시 윈도우를 이용한 새로운 저전력 LFSR 구조)

  • Kim Youbean;Yang Myung-Hoon;Lee Yong;Park Hyuntae;Kang Sungho
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.8 s.338
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    • pp.7-14
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    • 2005
  • This paper presents a new low power BIST TPG scheme. It uses a transition monitoring window (TMW) that is comprised of a transition monitoring window block and a MUX. When random test patterns are generated by an LFSR, transitions of those patterns satisfy pseudo-random gaussian distribution. The Proposed technique represses transitions of patterns using a k-value which is a standard that is obtained from the distribution of U to observe over transitive patterns causing high power dissipation in a scan chain. Experimental results show that the Proposed BIST TPG schemes can reduce scan transition by about $60\%$ without performance loss in ISCAS'89 benchmark circuits that have large number scan inputs.

A Study on the Construction of RDM in an Organization Using Big Data and Block Chain (빅데이터와 블록체인을 활용한 조직내 RDM 구축방안)

  • Lee, Kyung-Hee;Choi, Youngjin;Cho, Wan-Sup
    • The Journal of Bigdata
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    • v.4 no.2
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    • pp.127-139
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    • 2019
  • Research Data Management (RDM) is a system that encompasses people, policies, resources and technologies that provide and support directions in producing, collecting, using, and preserving research data. RDMs consist of a wide range of activities, including supporting the creation of data management plans (DMPs), building data collections and repositories, and digital preservation and distribution. In advanced countries, systems for RDMs and related organizations are well organized and functioning, but in Korea, the management system is insufficient due to low level of data awareness. In this paper, we propose a plan to establish a research data management system suitable for the reality. In particular, it is important to reflect in RDM that the construction of big data platforms for the collection and management of big data in each field and organization is increasing rapidly. Also, we will discuss how to provide data provision and researchers' data sovereignty using blockchain technology, and propose a P2P-based decentralized RDM scheme.

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Expression and Significance of Microsomal Prostaglandin Synthase-1 (mPGES-1) and Beclin-1 in the Development of Prostate Cancer

  • Xu, Lu-Wei;Qian, Ming;Jia, Rui-Peng;Xu, Zheng;Wu, Jian-Ping;Li, Wen-Cheng;Huang, Wen-Bin;Chen, Xing-Guo
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1639-1644
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    • 2012
  • The aim of this study was to investigate the expression and significance of microsomal prostaglandin synthase-1 (mPGES-1) and Beclin-1 in the development of prostate cancer (PCa). Immunohistochemistry was performed on paraffin-embedded sections with rabbit polyclonal against mPGES-1 and Beclin-1 in 40 PCa, 40 benign prostatic hyperplasia (BPH) and 10 normal prostate specimens for this purpose. Quantitative real-time polymerase chain reaction (qRT-PCR) was applied for mRNA expression of mPGES-1 and Beclin-1, while MTT assays were used to ascertain the best working concentration of the mPGES-1 inhibitor (CAY10526). The effect of CAY10526 treatment on expression of Beclin-1 in DU-145 cells was studied using Western blot analysis. Localization of Beclin-1 and mPGES-1 was in endochylema. Significant differences in expression was noted among PCa, BPH and normal issues (P<0.05). Beclin-1 expression inversely correlated with mPGES-1 expression in PCa tissue (P<0.05). CAY10526 could significantly block mPGES-1 expression and the proliferation of DU-145 cells (P<0.05), while increasing Beclin-1 levels (P<0.05). Overexpression of mPGES-1 could decrease the autophagic PCa cell death. Inhibiting the expression of mPGES-1 may lead to DU-145 cell death and up-regulation of Beclin-1. The results suggest that inhibition of mPGES-1 may have therapeutic potential for PCa in the future.

Effect of Insulin-like Growth Factor-1 on Bone Morphogenetic Protein-2 Expression in Hepatic Carcinoma SMMC7721 Cells through the p38 MAPK Signaling Pathway

  • Xu, Guan-Jun;Cai, Sheng;Wu, Jian-Bing
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1183-1186
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    • 2012
  • Objective: To observe the effect of insulin-like growth factor-1 (IGF-1) on bone morphogenetic protein (BMP)-2 expression in hepatocellular carcinoma SMMC7721 cells. Methods: Cells were divided into blank control, IGF-1, IGF-1 + SB203580, and SB203580 groups. SB203580 was used to block the p38 MAPK signaling pathway. Changes in the expression of BMP-2, p38 MAPK, and phosphorylated p38, MERK, ERK and JNK were determined using reverse transcription polymerase chain reactions (RT-PCR) and Western blot analysis. Results: Protein expression of phosphorylated BMP-2, MERK, ERK, and JNK was significantly up-regulated by IGF-1 compared with the control group ($1.138{\pm}0.065$ vs. $0.606{\pm}0.013$, $0.292{\pm}0.005$ vs. $0.150{\pm}0.081$, $0.378{\pm}0.006$ vs. $0.606{\pm}0.013$, and $0.299{\pm}0.015$ vs. $0.196{\pm}0.017$, respectively; P<0.05). Levels of BMP-2 and phosphorylated MERK and JNK were significantly reduced after blocking of the p38MAPK signaling pathway ($0.494{\pm}0.052$ vs. $0.165{\pm}0.017$, $0.073{\pm}0.07$ vs. $0.150{\pm}0.081$, and $0.018{\pm}0.008$ vs. $0.196{\pm}0.017$, respectively; P<0.05), but such a significant difference was not observed for phosphorylated ERK protein expression ($0.173{\pm}0.07$ vs. $0.150{\pm}0.081$, P>0.05). Conclusion: IGF-1 can up-regulate BMP-2 expression, and p38 MAPK signaling pathway blockage can noticeably reduce the up-regulated expression. We can conclude that the up-regulatory effect of IGF-1 on BMP-2 expression is realized through the p38 MAPK signaling pathway.

Selective Interaction Between Chloroplast β-ATPase and TGB1L88 Retards Severe Symptoms Caused by Alternanthera mosaic virus Infection

  • Seo, Eun-Young;Nam, Jiryun;Kim, Hyun-Seung;Park, Young-Hwan;Hong, Seok Myeong;Lakshman, Dilip;Bae, Hanhong;Hammond, John;Lim, Hyoun-Sub
    • The Plant Pathology Journal
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    • v.30 no.1
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    • pp.58-67
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    • 2014
  • The multifunctional triple gene block protein 1 (TGB1) of the Potexvirus Alternanthera mosaic virus (AltMV) has been reported to have silencing suppressor, cell-to-cell movement, and helicase functions. Yeast two hybrid screening using an Arabidopsis thaliana cDNA library with TGB1 as bait, and co-purification with TGB1 inclusion bodies identified several host proteins which interact with AltMV TGB1. Host protein interactions with TGB1 were confirmed by biomolecular fluorescence complementation, which showed positive TGB1 interaction with mitochondrial ATP synthase delta' chain subunit (ATP synthase delta'), light harvesting chlorophyll-protein complex I subunit A4 (LHCA4), chlorophyll a/b binding protein 1 (LHB1B2), chloroplast-localized IscA-like protein (ATCPISCA), and chloroplast ${\beta}$-ATPase. However, chloroplast ${\beta}$-ATPase interacts only with $TGB1_{L88}$, and not with weak silencing suppressor $TGB1_{L88}$. This selective interaction indicates that chloroplast ${\beta}$-ATPase is not required for AltMV movement and replication; however, TRV silencing of chloroplast ${\beta}$-ATPase in Nicotiana benthamiana induced severe tissue necrosis when plants were infected by AltMV $TGB1_{L88}$ but not AltMV $TGB1_{L88}$, suggesting that ${\beta}$-ATPase selectively responded to $TGB1_{L88}$ to induce defense responses.

Rumen Microbial Population in the In vitro Fermentation of Different Ratios of Forage and Concentrate in the Presence of Whole Lerak (Sapindus rarak) Fruit Extract

  • Suharti, Sri;Astuti, Dewi Apri;Wina, Elizabeth;Toharmat, Toto
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.8
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    • pp.1086-1091
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    • 2011
  • This experiment was designed to investigate the effect of lerak extract on the dynamic of rumen microbes in the in vitro fermentation of diet with different ratios of forage and concentrate. In vitro fermentation was conducted according to the method of Tilley and Terry (1963). The design of experiment was a factorial block design with 2 factors. The first factor was the ratio of forage and concentrate (90:10, 80:20, and 70:30 w/w) and the second factor was the level of lerak extract (0, 0.6, and 0.8 mg/ml). Total volatile fatty acid (VFA) concentration, proportional VFA and NH3 concentration were measured at 4 h incubation. Protozoal numbers in the buffered rumen fluid after 4 and 24 h of incubation were counted under a microscope. Bacterial DNAs of buffered rumen fluid were isolated from incubated samples after 24 h of incubation using a QiaAmp kit. Total bacteria, Fibrobacter succinogenes, Ruminococcus albus, and Prevotella ruminicola were quantified using real time polymerase chain reaction (PCR). Lerak extract markedly reduced protozoal numbers in buffered rumen fluid of all diets after 24 h of incubation. Total bacteria did not change with lerak extract addition. While no difference in F. succinogenes was found, there was a slight increase in R. albus number and a significant enhancement in P. ruminicola number by increasing the level of lerak extract in all diets. Propionate concentration significantly increased in the presence of lerak extract at level 0.8 mg/ml. It was concluded that the addition of lerak extract could modify rumen fermentation and had positive effects on rumen microbes.

A Study on Implementation of Authentication System for Home Networking Service (홈 네트워크 서비스를 위한 인증시스템 구현에 관한 연구)

  • Lee, Ki-Young
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.6
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    • pp.1091-1098
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    • 2009
  • In this paper, we designed the authentication system for home network service and applied it to actual sensor nodes. The pair-wise pre-distribution key skim is applied for prevention of authentication key from sniffing on the wireless sensor networks. The authentication key and data are encrypted by using the CBC mode RC5 algorithm based on the SPINS. The experimental environment consists of a base station (BS)and sensor nodes and each sensor node sends both sensing data and the encrypted authentication key to the BS. For simulations we set up some what-if scenarios of security menaces in home network service.Slightly modified the TOS_Msg data arrays of TinyOS is suggested to store 8-byte authentication key which can enable data encryption and authentication at the each sensor node. As a result, malfunction caused by communication between BS and nodes of other groups of added nodes having malicious purpose can be protected. Also, we confirmed that a critical data of home networking service like vital signal can be transmitted securely through this system by encryption technique.

Kinetic Consideration of Melt-copolymerization of Poly(butylene terephthalate) (PBT) and p-Acetoxybenzoic Acid (ABA) (폴리부틸렌테레프탈레이트와 파라아세톡시벤조산의 용융공중합 속도론에 대한 고찰)

  • 김도경;박수영;박종래
    • Polymer(Korea)
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    • v.24 no.1
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    • pp.16-22
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    • 2000
  • Poly(butylene terephthalate- co-oxybenzoate)(PBOT) containing mesogenic oxybenzoate units in the main chain was synthesized through ester exchange reaction by melt mixing of poly(butylene terephthalate)(PBT) and p-acetoxybenzoic acid (ABA). From the kinetics of the copolymerization reaction, the activation energies and the rate constants of homopolymerization and copolymerization, k$_{h}$ and k$_{c}$, could be determined. From the reaction conditions of different compositions, 4/6, 5/5, and 6/4 of PBT/ABA, at 250, 260, and 27$0^{\circ}C$, it was revealed that copolymerization between PBT and ABA proceeds on a pseudo-second order reaction if the ABA content and its conversion are low. In this case, the ratio of rate constants of homopolymerization to copolymerization was in the range from 1.08 to 3.17, indicating that the copolymer with more notable block character was obtained at the higher mole fraction of ABA and at higher temperature.e.e.

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