• Title/Summary/Keyword: long-distance signaling

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A study on the long distance data transmission of underwater acoustic sensor (수중 음향센서의 원거리 데이터 전송에 관한 연구)

  • Han, Jeong-Hee;Lee, Byung-Hwa;Kim, Dong-Wook;Lee, Jeong-Min
    • The Journal of the Acoustical Society of Korea
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    • v.38 no.2
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    • pp.240-245
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    • 2019
  • This paper is a study result on long distance transmission of underwater acoustic sensor data over cable. The data transceiver is designed using the LVDS (Low Voltage Differential Signaling) transmission scheme, and the jitter characteristics are analyzed by measuring the long distance transmission signal through the cable. In order to reduce the jitter, a pre-emphasis technique is applied to compensate the transmitting signal to be attenuated by long distance transmission, and the transmission characteristics were verified according to the distance.

Long-Distance Control of Nodulation: Molecules and Models

  • Magori, Shimpei;Kawaguchi, Masayoshi
    • Molecules and Cells
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    • v.27 no.2
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    • pp.129-134
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    • 2009
  • Legume plants develop root nodules to recruit nitrogen-fixing bacteria called rhizobia. This symbiotic relationship allows the host plants to grow even under nitrogen limiting environment. Since nodule development is an energetically expensive process, the number of nodules should be tightly controlled by the host plants. For this purpose, legume plants utilize a long-distance signaling known as autoregulation of nodulation (AON). AON signaling in legumes has been extensively studied over decades but the underlying molecular mechanism had been largely unclear until recently. With the advent of the model legumes, L. japonicus and M. truncatula, we have been seeing a great progress including isolation of the AON-associated receptor kinase. Here, we summarize recent studies on AON and discuss an updated view of the long-distance control of nodulation.

Properties and Performance of Space-Time Bit-Interleaved Coded Modulation Systems in Fast Rayleigh Fading Channels

  • Park, Dae-Young;Byun, Myung-Kwang;Lee, Byeong-Gi
    • Journal of Communications and Networks
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    • v.6 no.1
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    • pp.1-8
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    • 2004
  • In this paper, we investigate the properties and performance of space-time bit-interleaved coded modulation (STBICM) systems in fast Rayleigh fading channels. We first show that ST-BICM with QPSK signaling in fast fading channels possesses the uniform distance property, which makes performance analysis tractable. We also derive the probability distribution of the squared Euclidean distance between space-time symbols assuming uniform bit-interleaving. Based on the distribution, we show that the diversity order for each codeword pair becomes maximized as the frame length becomes sufficiently long. This maximum diversity order property implies that the bit-interleaver transforms an ST-BICM system over transmit diversity channels into an equivalent coded BPSK system over independent fading channels. We analyze the performance of ST-BICM in fast fading channels by deriving an FER upper bound. The derived bound turns out very accurate, requiring only the distance spectrum of the binary channel codes of ST-BICM. Numerical results demonstrate that the bound is tight enough to render an accurate estimate of performance of ST-BICM systems.

Hierarchical Home Agent Handover in Mobile IP (Mobile IP 에서의 계층적인 Home Agent Handover 기법)

  • Kim, Hyun-Seok;Park, Sung-Han
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.43 no.12 s.354
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    • pp.89-94
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    • 2006
  • In the Mobile IP, the movement of Mobile Host(MH) causes packets to be transmitted through a long route. A Correspond Node(CN) first communicate with a Home Agent(HA) when a Mobile Host moved from one subnet to another subnet. The HH-MIP algorithm reduces an inefficient transmission of packets by regarding a Foreign Agent(FA) near a mobile host as a Temporary Home Agent(THA). However, The algorithm costs the unnecessary signaling by measuring the distance of route between a FA and a THA for handover in the case that a Mobile host comes from a THA which a current FA never communicated. To solve this problem, we propose a scheme called Hierarchical Home Agent Handover in Mobile IP(HHH-MIP) algorithm. Our HHH-MIP algorithm only searches tables in a router by using the hierarchical structure between a FA and a THA. The simulation results show that the HHH-MIP algorithm reduces the additional signaling cost.

A Comparative Analysis on the Operating System of Urban Railway & Conventional·High speed Railway (도시철도와 일반·고속철도의 운영방식에 관한 비교 분석)

  • Choi, Jong-Gil;Yun, Hak-Sun
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.8
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    • pp.953-958
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    • 2015
  • Generally, Urban railway have special characteristics with short distance journey and minimum headway intercity transportation. These days, urban railway operators choose the driverless operation system without driver. On the contrary, Conventional & high speed railway utilize for long distance and high speed running. Because of special conditions of freight railway operation compared with urban railway, operation of conventional & high speed railway is showed very different characteristics. In this paper, We compares different operation scheme of urban railway and conventional & high speed railway and then present condition for train control system based on radio.

Post Genomic Approaches to Nodulation in Soybean

  • Hwang, Cheol-Ho;Lim, Chae-Woo
    • The Plant Pathology Journal
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    • v.20 no.1
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    • pp.13-17
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    • 2004
  • An interaction between Legumes and Rhizobia establishes a symbiotic new organ, the nodule that supports atmospheric nitrogen fIxation. The specific communications between the microbes and legume plants are necessary for both nodulation and nitrogen fixation. Through genetic and biochemical analyses several genes playing pivotal roles in nodulation had been identified to be a receptor kinase like CALVATAl involved signal transduction for development. This emphasizes peptides as signals to be transmitted for a short or long distance transport for nodulation. In addition, a quorum sensing in rhizobia has become a focus as counterpart signal. In an attempt to reveal proteins factors and signaling molecules acting on nodulation, proteome analyses of nodule and the proteins in apoplast upon communication between Legumes and Rhizobia were performed.

A Study on Principles for Safe Driving of the Urban Railway Train (도시철도 열차의 안전 운전원칙에 관한 연구)

  • Jeon, Young-Seok;Ahn, Seung-Ho;Chung, Kwang-Woo;Kim, Jae-Moon;Kim, Chul-Su;Chung, Jong-Duk;Jeong, Rag-Gyo
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.628-635
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    • 2009
  • To assure the safety of urban railway train, it is necessary to observe the specified driving principles under an essential condition during running on tracks. These principles arises from a great deal of experience for a long time and include safe distance between trains, the railway signaling, block system, regular block of the highest priority and driving prohibition of simple railway vehicle in the main track, etc. Therefore, it is important to apply these principles to domestic urban railway driving regulations and railway vehicle driving regulations. However, domestic urban railway administrator established his own operation rules within the regulation. In this study, domestic urban railway administration's own rules are examined and the appropriate driving regulation on the safe driving principles is proposed.

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Performance Analysis on Code-Division Multiple Access in Underwater Acoustic Sensor Network (수중 음향 센서 망에서의 코드 분할 다중 접속 기법에 대한 성능 해석)

  • Seo, Bo-Min;Cho, Ho-Shin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.9A
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    • pp.874-881
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    • 2010
  • Acoustic signal, which is a main carrier of underwater communication, attenuates along the traveled path heavily depending on the frequency as well as inter-node distance. In addition, since it has a long propagation delay, the conventional medium access control (MAC) schemes requiring complex signaling procedures and accordingly heavy overhead messages would not be appropriate in underwater communications. In this paper, we propose a code division multiple access (CDMA) scheme as a solution for MAC of underwater communication and evaluate the performance. A hierarchical data-gathering tree topology is considered and a staggered wake-up pattern is employed for the purpose of energy saving. As a performance measure, the data rate at each level of hierarchical topology is derived.

Genome-wide analysis of Solanum lycopersicum L. cyclophilins

  • Khatun, Khadiza;Robin, Arif Hasan Khan;Islam, Md. Rafiqul;Jyoti, Subroto Das;Lee, Do-Jin;Kim, Chang Kil;Chung, Mi-Young
    • Journal of Plant Biotechnology
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    • v.49 no.1
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    • pp.15-29
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    • 2022
  • Cyclophilins (CYPs) are highly conserved ubiquitous proteins belong to the peptidyl prolyl cis/trans isomerase (PPIase) superfamily. These proteins are present in a wide range of organisms; they contain a highly conserved peptidyl-prolyl cis/trans isomerase domain. A comprehensive database survey identified a total of 35 genes localized in all cellular compartments of Solanum lycopersicum L., but largely in the cytosol. Sequence alignment and conserved motif analyses of the SlCYP proteins revealed a highly conserved CLD motif. Evolutionary analysis predicted the clustering of a large number of gene pairs with high sequence similarity. Expression analysis using the RNA-Seq data showed that the majority of the SlCYP genes were highly expressed in mature leaves and blooming flowers, compared with their expression in other organs. This study provides a basis for the functional characterization of individual CYP genes in the future to elucidate their role(s) in protein refolding and long-distance signaling in tomatoes and in plant biology, in general.

On Slimming down the Functions Room of Light Rail Transit Stations by Utilizing an Enhanced DSM Method (개선된 DSM 기법을 통한 경전철 정거장 기능실의 슬림화에 관한 연구)

  • Kim, Joo-Uk;Park, Kee-Jun;Kim, Young-Min;Lee, Jae-Chon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.2
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    • pp.927-939
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    • 2015
  • It appears that the rapid advance in technology has allowed to broaden the variety of rail systems technology, thereby fostering new business opportunity in rail industry. The direction of rail systems operations is mainly two fold. In one direction, long distance operations between mega cities are pursued with help of high speed trains under development. In the other case, relatively short distance operations for covering intra-city or suburban area are becoming popular. A good example of the latter case is light rail transit (LRT) systems. Due to the short distance operation, it is thus expected that both the development and operation cost for LRT systems be reduced to some extent. The cost reduction desired in there can be gained by scaling down the sizes of both the trains and stations as compared to those of normal rail systems. However, it is not well known how the LRT stations can be scaled down. The objective of this paper is to study on how to slim down the stations (particularly, the functions room) of LRT systems. To achieve the objective, an approach is studied based on a modified method of design structure matrix (DSM). Specifically, using the enhanced DSM method, an integrated architecture is developed for the functions room, in which equipments are housed to perform the functions of electricity, signaling, and communication for LRT stations. The use of the result indicates that the desired reduction can be obtained with the approach taken in the paper.