• Title/Summary/Keyword: Repeat System

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QoS Analysis of Wireless Sensor Network with ARQ Scheme (ARQ 방식을 적용한 무선 센서 네트워크의 QoS 해석)

  • Roh, Jae-Sung;Kim, Wan-Tae
    • Journal of Advanced Navigation Technology
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    • v.14 no.1
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    • pp.49-56
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    • 2010
  • Severe energy constraints and the low power consumption require the significance of the energy efficient error control mechanisms in wireless sensor network (WSN). In this paper, an automatic repeat request (ARQ) methodology for the analysis of error control schemes in WSN is presented such that the effects of packet length, the modulation scheme and the interference effect of the wireless channel are investigated. Moreover, an analyis of ARQ error control is provided by considering two major architectures for wireless sensor network, i.e., Mica2 and MicaZ sensor nodes. And the throughput performance of WSN with asynchronous FSK signal and DSSS-OQPSK signal with selective repeat ARQ scheme are analyzed in multiple interference environment, and the probability of receiving a correct bit and packet from target node to sink node is evaluated as a function of the channel parameter, the number of wireless sensor node, and the spreading factor.

S-ARQ: A New Truncated ARQ for IP-Based Wireless Network

  • Choi, Young-Kyu;Oh, Seong-Jun;Choi, Sung-Hyun
    • Journal of Communications and Networks
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    • v.12 no.2
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    • pp.174-180
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    • 2010
  • Automatic Repeat reQuest (ARQ) is a very effective technique against transmission error at the medium access control (MAC) layer. An erroneous MAC protocol data unit can be typically retransmitted within a given limit. In order to improve the IP-level performance, which directly affects the user-perceived quality-of-service (QoS), we propose a new truncated ARQ strategy, called MAC service data unit-based ARQ (S-ARQ), where the finite number of opportunities for retransmissions are shared by multiple fragments out of an IP datagram. We describe how SARQ can be implemented in a practical system, and then propose another variant of S-ARQ employing a functionality called early detection of failure. Basically, we evaluate the performance of SARQ in two different manners. First, assuming i.i.d. error process, we analyze both the probability of the delivery failure and the average delay of IP datagram. Then, we assess the performance of S-ARQ via simulation over a 2-state Markov channel.

A Model of the Risk Response Repeat Process in the Construction Project (건설공사 위험대응 반복 프로세스 모델)

  • Kim Seon-Gyoo
    • Korean Journal of Construction Engineering and Management
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    • v.3 no.1 s.9
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    • pp.107-114
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    • 2002
  • Recently, a few major construction companies in Korea have a growing interests to the risk management system, and they are trying to apply it to their construction projects. However, the existing methodologies to be applied to the foreign public projects are not proper to the construction environments due to its adaptabilities, that has one time process and heavily depends on personal judgement. The purpose of this paper is to propose a risk response process in consideration of the residual risks, which would be more adaptable and practical in the construction environment, overcoming the current obstacles to be mentioned above. This process has systematic repeat process until the residual risks go down to the risk thresholds based on the efficiency of specific response strategy.

Factors Affecting Patient Satisfaction of Dental Services Organizations (치과의료서비스에 대한 환자만족 영향원인 -경남 일부 지역 치과의원을 중심으로-)

  • Lee, Eun-Sook;Park, Jeong-Ran;Choi, Mi-Sook
    • Journal of Korean society of Dental Hygiene
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    • v.5 no.2
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    • pp.247-261
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    • 2005
  • The main objective of this study is to investigate the factors affecting patient satisfaction, repeat-use intention, and inducement intention for providing the suggestion for patient-oriented management of dental services organizations. For this study, the patient satisfaction model including 14 facets of satisfaction factors such as distance(time/location), human services(dentist-hygienist), treatment results, and facilities(convenient facilities/parking lot) was examined. Data were collected from 196 patients who visiting the same dental services organization more than two times of ten dental clinics at Kyeongsangnam-do area using self-administered questionnaire. Major results of the empirical analysis are as follows: First, patient satisfaction, repeat-use intention, and inducement intention were significantly correlated with gender, age, economic conditions among patients of dental clinics. Second, kindness of hygienist, treatment results, kindness of receptionist, waiting time, emergency medical services, and right-fee for services were found to have significant influence on dental services organizations. These research findings suggest that improvement of service quality in dental care and advancement in treatment ability of dentist and hygienist are very important to improve patient satisfaction and patient-oriented service system in dental services organizations.

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LDPC Coding for image data and FPGA Implementation of LDPC Decoder (영상 정보의 LDPC 부호화 및 복호기의 FPGA구현)

  • Kim, Jin Su;Jaegal, Dong;Byon, Kun Sik
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.05a
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    • pp.887-890
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    • 2009
  • To transmit information over a channel in the presence of noise, there needs some technique to code the information. One of the coding techniques used for error detection and correction close to the Shannon limit is Low Density Parity Code. LDPC and decoding characteristic features by sum-product algorithm are matched for the performance to Turbo Code, RA(Repeat Accumulate) code, in case of very long code length of LDPC surpass their performance. This paper explains LDPC coding scheme of image data and decoding scheme, implements LDPC decoder in FPGA.

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Expression and phosphorylation analysis of soluble proteins and membrane-localised receptor-like kinases from Arabidopsis thaliana in Escherichia coli

  • Oh, Eun-Seok;Eva, Foyjunnaher;Kim, Sang-Yun;Oh, Man-Ho
    • Journal of Plant Biotechnology
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    • v.45 no.4
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    • pp.315-321
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    • 2018
  • Molecular and functional characterization of proteins and their levels is of great interest in understanding the mechanism of diverse cellular processes. In this study, we report on the convenient Escherichia coli-based protein expression system that allows recombinant of soluble proteins expression and cytosolic domain of membrane-localised kinases, followed by the detection of autophosphorylation activity in protein kinases. This approach is applied to regulatory proteins of Arabidopsis thaliana, including 14-3-3, calmodulin, calcium-dependent protein kinase, TERMINAL FLOWER 1(TFL1), FLOWERING LOCUS T (FT), receptor-like cytoplasmic kinase and cytoplasmic domain of leucine-rich repeat-receptor like kinase proteins. Our Western blot analysis which uses phospho-specific antibodies showed that five putative LRR-RLKs and two putative RLCKs have autophosphorylation activity in vitro on threonine and/or tyrosine residue(s), suggesting their potential role in signal transduction pathways. Our findings were also discussed in the broader context of recombinant expression and biochemical analysis of soluble and membrane-localised receptor kinases in microbial systems.

A Review of Extended STR Loci and DNA Database

  • Cho, Yoonjung;Lee, Min Ho;Kim, Su Jin;Park, Ji Hwan;Jung, Ju Yeon
    • Biomedical Science Letters
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    • v.28 no.3
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    • pp.157-169
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    • 2022
  • DNA typing is the typical technology in the forensic science and plays a significant role in the personal identification of victims and suspects. Short tandem repeat (STR) is the short tandemly repeated DNA sequence consisting of 2~7 bp DNA units in specific loci. It is disseminated across the human genome and represents polymorphism among individuals. Because polymorphism is a key feature of the application of DNA typing STR analysis, STR analysis becomes the standard technology in forensics. Therefore, the DNA database (DNA-DB) was first introduced with 4 essential STR markers for the application of forensic science; however, the number of STR markers was expanded from 4 to 13 and 13 to 20 later to counteract the continuously increased DNA profile and other needed situations. After applying expanded STR markers to the South Korean DNA-DB system, it positively affected to low copy number analysis that had a high possibility of partial DNA profiles, and especially contributed to the theft cases due to the high portion of touch DNA evidence in the theft case. Furthermore, STR marker expansion not only contributed to the resolution of cold cases but also increased kinship index indicating the potential for improved kinship test accuracy using extended STR markers. Collectively, the expansion of the STR locus was considered to be necessary to keep pace with the continuously increasing DNA profile, and to improve the data integrity of the DNA-DB.

A Study on the Frequency Hopping Code Division Multiple Access System (주파수도약 부호분할다원접속 방식에 관한 연구)

  • 한경섭;한영열;심수보
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.12 no.5
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    • pp.535-542
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    • 1987
  • In this paper, Modified system of the asynchronous repeat FH/MFSK transmission system is proposed. By transmitting data bits less that address bits, we can improue the system performance, we have evaluated the probability of word error of modified system and compared with the conventional system. And it is found that the modified system shows the improved performance. Also the structure of the receiver is remarkably simplified with the comparison of the conventional system.

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Intertidal DEM Generation Using Satellite Radar Interferometry (인공위성 레이더 간섭기술을 이용한 조간대 지형도 작성에 관한 연구)

  • Park, Jeong-Won;Choi, Jung-Hyun;Lee, Yoon-Kyung;Won, Joong-Sun
    • Korean Journal of Remote Sensing
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    • v.28 no.1
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    • pp.121-128
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    • 2012
  • High resolution intertidal DEM is a basic material for science research like sedimentation/erosion by ocean current, and is invaluable in a monitoring of environmental changes and practical management of coastal wetland. Since the intertidal zone changes rapidly by the inflow of fluvial debris and tide condition, remote sensing is an effective tool for observing large areas in short time. Although radar interferometry is one of the well-known techniques for generating high resolution DEM, conventional repeat-pass interferometry has difficulty on acquiring enough coherence over tidal flat due to the limited exposure time and the rapid changes in surface condition. In order to overcome these constraints, we tested the feasibility of radar interferometry using Cosmo-SkyMed tandem-like one-day data and ERS-ENVISAT cross tandem data with very short revisit period compared to the conventional repeat pass data. Small temporal baseline combined with long perpendicular baseline allowed high coherence over most of the exposed tidal flat surface in both observations. However the interferometric phases acquired from Cosmo-SkyMed data suffer from atmospheric delay and changes in soil moisture contents. The ERS-ENVISAT pair, on the other hand, provides nice phase which agree well with the real topography, because the atmospheric effect in 30-minute gap is almost same to both images so that they are cancelled out in the interferometric process. Thus, the cross interferometry with very small temporal baseline and large perpendicular baseline is one of the most reliable solutions for the intertidal DEM construction which requires very accurate mapping of the elevation.

Study Protocol for the Most Effective Recall Method in a Cervical Cancer Screening Program in Klang, Malaysia

  • Rashid, Rima Marhayu Abdul;Dahlui, Maznah
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.10
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    • pp.5867-5870
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    • 2013
  • Background: Cervical cancer is the second most common cancer among Malaysian women with an ASR of 17.9 and a mortality rate of 5.6 per 100,000 population in 2008 (GLOBOCAN, 2008). The 5 year prevalence was estimated to be 14.5 per 100,000 population. As the second most common cancer affecting productive females, cervical cancer imposes an impact to the socioeconomic aspect of the country. However, the poor uptake of cervical cancer screening is a major problem in detecting early pre-cancerous lesions and thus, delay in initiating treatment for cervical cancer. Realizing the urgency to increase the uptake of PAP smear, besides enhancing the promotion of PAP smear screening for women above 35 years old, the call-recall system for pap smear screening had been piloted in one of the suburban districts which aimed to improve regular participation of women for cervical and breast cancer screening. This is of public health importance as identifying the best feasible option to increase patient's respond to participate in the screening program effectively in our setting will be helpful in implementing an organized regular population based screening program tailored to our setting. The pilot program of cervical cancer screening in Klang was an opportunity to assess different options in recalling patients for a repeat pap smear to increase their participation and adherence to the program. Methods and Results: This was a population based randomized control trial. Women aged 20-65 years in the population that matched the inclusion and exclusion criteria were re-called for a repeat smear. There are four different intervention groups; letter, registered letters, short messages services (SMS) and phone calls where 250 subjects were recruited into each group. Samples were generated randomly from the same population in Klang into four different groups. The first group received a recall letter for a repeat smear similar to the one that has been given during the first invitation. The intervention groups were either be given a registered letter, an SMS or a phone call to re-call them. The socio-demographic data of the patients who came for uptake were collected for further analysis. All the groups were followed up after 8 weeks to assess their compliance to the recall. Conclusions: The study will provide recommendations about the most effective methods for recall in a population based pap smear screening program on two outcomes: i) patients response; ii) uptake for repeat pap smear.