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Study on algorithm of blind modulation detector in EDGE systems (EDGE 시스템에서 블라인드 변조 검출기의 알고리즘에 관한 연구)

  • Park, Hong-Won;Moon, Hong-Youl;Woo, Sung-Hyun;Kim, Jin-Hee
    • Aerospace Engineering and Technology
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    • v.9 no.1
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    • pp.67-71
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    • 2010
  • In this study, an algorithm for blind modulation detection in EDGE systems is presented. EDGE introduces an 8PSK modulation to provide high-speed data rates in addition to the existing GSM system. A transmitter may switch dynamically the modulation and coding schemes for transmission of data according to the channel quality. To decode the data correctly, the receiver has to detect using only training sequence which modulation is being used. Basically the property of one radio block composed of four bursts to detect effectively the modulation scheme even under severe conditions is used. More specifically, the reference value calculated for received burst is accumulated with previous reference value to minimize statistically the false detection probability in one radio block. Also each burst data having different modulation from the modulation of the fourth burst is set to zero to improve the decoding performance because the reference of the fourth burst has the highest reliability.

Implementations of Hypercube Networks based on TCP/IP for PC Clusters (PC 클러스터를 위한 TCP/IP 기반 하이퍼큐브 네트워크 구현)

  • Lee, Hyung-Bong;Hong, Joon-Pyo;Kim, Young-Tae
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.2
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    • pp.221-233
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    • 2008
  • In general, we use a Parallel processing computer manufactured specially for the purpose of parallel processing to do high performance computings. But we can depoly and use a PC cluster composed of several common PCs instead of the very expensive parallel processing computer. A common way to get a PC cluster is to adopt the star topology network connected by a switch hub. But in this paper, we grope efficient implementations of hypercube networks based on TCP/IP to connect 8 PCs directly for more useful parallel processing environment, and make evaluations on functionality and efficiency of them using ping, netperf, MPICH. The two proposed methods of implementation are IP configuration based on link and IP configuration based on node. The results of comparison between them show that there is not obvious difference in performance but the latter is more efficient in simplicity of routing table. For verification of functionality, we compare the parallel processing results of an application in them with the same in a star network based PC cluster. These results also show that the proposed hypercube networks support a perfect parallel processing environment respectively.

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A New Insight of Salt Stress Signaling in Plant

  • Park, Hee Jin;Kim, Woe-Yeon;Yun, Dae-Jin
    • Molecules and Cells
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    • v.39 no.6
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    • pp.447-459
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    • 2016
  • Many studies have been conducted to understand plant stress responses to salinity because irrigation-dependent salt accumulation compromises crop productivity and also to understand the mechanism through which some plants thrive under saline conditions. As mechanistic understanding has increased during the last decades, discovery-oriented approaches have begun to identify genetic determinants of salt tolerance. In addition to osmolytes, osmoprotectants, radical detoxification, ion transport systems, and changes in hormone levels and hormone-guided communications, the Salt Overly Sensitive (SOS) pathway has emerged to be a major defense mechanism. However, the mechanism by which the components of the SOS pathway are integrated to ultimately orchestrate plant-wide tolerance to salinity stress remains unclear. A higher-level control mechanism has recently emerged as a result of recognizing the involvement of GIGANTEA (GI), a protein involved in maintaining the plant circadian clock and control switch in flowering. The loss of GI function confers high tolerance to salt stress via its interaction with the components of the SOS pathway. The mechanism underlying this observation indicates the association between GI and the SOS pathway and thus, given the key influence of the circadian clock and the pathway on photoperiodic flowering, the association between GI and SOS can regulate growth and stress tolerance. In this review, we will analyze the components of the SOS pathways, with emphasis on the integration of components recognized as hallmarks of a halophytic lifestyle.

New Roles of Glucose-Specific Enzyme IIA of the Vibrio vulnificus Phosphoransferase System

  • Kim, You-Jin;Koo, Byoung-Mo;Ryu, Yang-Kyun;Park, Soon-Jung;Lee, Kyu-Ho;Seok, Yeong-Jae
    • Proceedings of the Microbiological Society of Korea Conference
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    • 2006.05a
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    • pp.29-31
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    • 2006
  • In a previous report, we showed that enzyme $IIA^{Glc}(EIIA^{Glc}$ of Escherichia coli phosphotransferase system (PTS) interacts with and regulates activity of FrsA (fermentation/respiration switch protein). A BLAST search revealed that orthologs of FrsA exist only in some Gram-negative bacteria such as E. coli, Salmonella typhimurium, Shigella flexneri, Yersinia pestis, Vibrio cholerae, Vibrio vulnificus, Vibrio parahemeolyticus, and Photorhabdus luminescens and all of these species are facultative anaerobes belonging to the ${\gamma}-proteobacterial$ group, and most of them are highly pathogenic. Ligand-fishing experiments using $EIIA^{Glc}$ of Vibrio vulnificus ($vEIIA^{Glc}$) as bait revealed that $vEIIA^{Glc}$ also interacts with vFrsA in a phosphorylation state-dependent manner. The frsA mutant of Vibrio vulnificus showed remarkably reduced cytotoxicity to HeLa cells and reduced lethality to mice compared to wild type. Comparison of extracellular proteomes between the mutant and wild type indicated that hemolysin was not produced in the frsA mutant. Characterization of another protein interacting with $vEIIA^{Glc}$ will be discussed.

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Computer Simulation on the Poling Mechanism for the Control of 2nd Order Optical Nonlinearity in Silica Glass (2차 비선형 광특성의 제어를 위한 실리카 유리의 전기분극 기구 전산모사)

  • Yu, Ung-Hyeon;Lee, Seung-Gyu;Sin, Dong-Uk;Jeong, Yong-Jae
    • Korean Journal of Materials Research
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    • v.11 no.3
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    • pp.207-214
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    • 2001
  • Silica glass is a core material for optical fiber in optical telecommunications, but its centrosymmetry eliminates the second order nonlinearity. But it is experimentally well known that the space charge polarization induces the Second Harmonic Generation (SHG) when a strong DC voltage is applied to silica glass for a long period of time with metal blocking electrodes. In this report, the results of a theoretical calculation of the nonlinear optical property caused by the space charge polarization, and a model of a numerical analysis to predict the small chance in nonlinear optical property as functions of time and space are provided. Assuming that amorphous silica is a solid state electrolyte and sodium ion is the only mobile charge carrier, 'Finite Difference Method' was employed for modeling of numerical analysis. The distributions of the concentration of sodium ion and electric field as functions of a normalized length of the specimen and a normalized applied voltage were simulated.

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Comparison of Clinical Development and Evaluation of Triple Antihypertensive Therapy in Advanced Foreign Countries (항고혈압 약물 3종 복합제에 대한 선진 외국의 임상자료 심사사례 비교)

  • Wang, So Young;Shon, Soo Jung;Um, Jung Yoon;Lim, Hwa Kyung;Lim, Sook;Kang, Seung Ho;Lee, Sun Hee
    • Korean Journal of Clinical Pharmacy
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    • v.23 no.3
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    • pp.239-247
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    • 2013
  • Background: Fixed drug combinations are formulations containing two or more active ingredients in a single dosage form. Such combination therapies are commonly applied to improve efficacy, reduce adverse events and replace co-administration, etc. National and international guidelines for hypertension treatment recommend addition of other classes of antihypertensive drugs rather than incremental dose of mono-therapy, when blood pressure is not adequately controlled. Thus, many dual combinations of antihypertensive drugs have been approved and pharmaceutical companies are recently interested in developing antihypertensive triple combinations. Clinical trial designs for the fixed combinations are various depending on the target patients, dosage and clinical endpoints. Thereby, further discussions for the clinical trials of antihypertensive triple therapies are required regarding the indication claimed. Conclusion: This article provides a review for the assessment of the label and medical reports of the clinical trials on antihypertensive triple therapies in advanced foreign countries.

A Simplified QoS Model for MPLS Networks (MPLS 네트워크를 위한 간략화된 QoS 모델)

  • Seo Seung-Joon;Kang Chul-Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.4B
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    • pp.235-245
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    • 2005
  • In this paper, a simplified QoS model of MPLS-based backbone network. Conventional scheme proposed by IETF(IETF schem) is to embed a DiffServ model in MPLS network. However, this approach results in overall upgrade of MPLS system and so it is difficult to deploy this approach. Our proposed model, however, uses a Vidual Link which is a set of Label Switched Path(LSP) connected from an Ingress Label Edge Router(LER) to an Egress LER. In this model, Per-Hop-Behavior(PHB) is implemented only at each LSP in ingress LER and Core Label Switch Routers(LSRs) just guarantee each LSP's bandwidth, not service. This bandwidth guarantee service is fully provided by legacy MPLS model. Also we propose flow allocation mechanism and the flow distribution among LSPs of the virtual link by the flow according to the network status. To evaluate the simplified approach, the characteristics of the approach are compared logically with these of IETF's one through simulations.

Investigation on the Nonideality of 12-Bit Sigma-Delta Modulator with a Signal Bandwidth of 1 MHz (1MHz 신호 대역폭출 갖는 12-비트 Sigma-Delta 변조기의 비이상성에 대한 조사)

  • 최경진;조성익;신홍규
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.11A
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    • pp.1812-1819
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    • 2001
  • In this paper, it investigated the permitted limit of the analog nonideality for the SOSOC Σ-Δ modulator design which is satisfied with 1 [MHz] signal bandwidth and 12-bit resolution in the OSR=25. Firstly, it get the SOSOC Σ-Δ modulator model and gain coefficient which is suitable in low voltage for the Σ-Δ modulator design which is satisfied with the specification in the supply voltage 3.3 [Vl. And it provided the performance prediction of the Σ-Δ modulator and the permitted limit of the nonideality by adding the performance degradation facts of the Σ-Δ modulator such as the finite gain of the amplifier, the SR, the closed-loop pole, the switch ON resistance and the capacitor mismatch to the ideal Σ-Δ modulator model. When designed the Σ-Δ modulator which is satisfied with the specification by the base above, it will be able to predict the performance of the Σ-Δ modulator and the guide for the specification of the circuit which composes the Σ-Δ modulator.

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Fault Management in Multichannel ATM Switches (다중 채널 ATM 스위치에서의 장애 관리)

  • 오민석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.8A
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    • pp.569-580
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    • 2003
  • One of the important advantages of multichannel switches is the incorporation of inherent fault tolerance into the switching fabric. For example, if a link which belongs to the multichannel group fails, the remaining links can assume responsibility for some of the traffic on the failed link. On the other hand, if faults occur in the switching elements, it can lead to erroneous routing and sequencing in the multichannel switch. We investigate several fault localization algorithms in multichannel crossbar ATM switches with a view to early fault recovery, The optimal algorithm gives the best performance in terms of time to localization but is computationally complex which makes it difficult to implement. We develop an on-line algorithm which is computationally mote efficient than the optimal algorithm. We evaluate its performance through simulation. The simulation results show that performance of the on line algorithm is only slightly sub-optimal for both random and bursty traffic. Finally a fault recovery algorithm is described which utilizes the information provided by the fault localization algorithm.

Improving Bootup Time of Embedded Linux using Snapshot Image Created on Boot Time (부팅 시 생성한 스냅샷 이미지를 이용한 임베디드 리눅스의 부팅 속도 향상 방안)

  • Joe, In-Whee;Lee, Sang-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.3B
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    • pp.254-259
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    • 2011
  • This paper attempts to propose a method to improve the snapshot boot method, one of the methods to enhance the booting speed of the embedded Linux based system and to increase its efficiency. Snapshot boot is a method of using suspend/resume that is a method of saving and restoring the entire information of the current tasks, and it enhances the booting speed by processing a restoration of previous tasks from the bootloader instead of processing the Linux booting. The facing problem of snapshot boot is that it takes a long time to create images and save them to the storage device during the suspend process since it targets every pages. Additionally, if the switch is turned off while creating an image by some extraordinary circumstances, then the image is not created and thus, the resume process of snapshot boot cannot be executed. The suggest method in this paper creates the snapshot image for once only and utilize the image to enhance the speed and stability on booting.