• 제목/요약/키워드: Random Early Detection

검색결과 99건 처리시간 0.034초

Performance Improvement on RED Based Gateway in TCP Communication Network

  • Prabhavat, Sumet;Varakulsiripunth, Ruttikorn
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2004년도 ICCAS
    • /
    • pp.782-787
    • /
    • 2004
  • Internet Engineering Task Force (IETF) has been considering the deployment of the Random Early Detection (RED) in order to avoid the increasing of packet loss rates which caused by an exponential increase in network traffic and buffer overflow. Although RED mechanism can prevent buffer overflow and hence reduce an average values of packet loss rates, but this technique is ineffective in preventing the consecutive drop in the high traffic condition. Moreover, it increases a probability and average number of consecutive dropped packet in the low traffic condition (named as "uncritical condition"). RED mechanism effects to TCP congestion control that build up the consecutive of the unnecessary transmission rate reducing; lead to low utilization on the link and consequently degrade the network performance. To overcome these problems, we have proposed a new mechanism, named as Extended Drop slope RED (ExRED) mechanism, by modifying the traditional RED. The numerical and simulation results show that our proposed mechanism reduces a drop probability in the uncritical condition.

  • PDF

국내 비만 초등학생들의 식이와 운동 중재 효과에 대한 체계적 문헌고찰 및 메타분석 (Systematic Review and Meta-analysis of Dietary and Exercise Intervention Effects of Obesity Elementary School Students in Korea)

  • 송혜영;양숙자;최윤
    • 한국보건간호학회지
    • /
    • 제32권2호
    • /
    • pp.194-207
    • /
    • 2018
  • Purpose: The purpose of this study was to identify the trends regarding diet and exercise intervention studies for Korean obese children between 2010 and 2017. Methods: This study was synthesized and reviewed systematically by meta-analysis. In addition, a total of thirty nine studies were investigated. The random effect model was used for meta-analysis. Results: Most studies used single interventions and that their theoretical frameworks still required improvement. In addition, on-line education programs still need to increase their number over that of off-line ones. Regarding the dependent variables for understandings the influences obesity may have on Korean children, most studies took advantage of biological indicators. In terms of the effects of obesity management programs, multiple interventions have gained a competitive edge over single ones for Korean obese children's diet and exercise. In a similar vein, healthy eating habits and adequate physical activities would have more positive effects on Korean children' obesity management programs. Conclusion: Further various studies will be needed for the early detection and prevention of obese children through varied interventions and qualitative improvement of studies.

중성자속잡음 신호를 이용한 원자로의 전동감시 (Vibration Monitoring of Reactor Internals Using Excore Neutron Flux Noise Signals)

  • 김성호;강현국;성풍현;한상준;전종선
    • 소음진동
    • /
    • 제5권3호
    • /
    • pp.361-371
    • /
    • 1995
  • The vibration of reactor internals should be monitored and diagnosed for the early detection of the failure of reactor pressure vessel. This can be performed by analyzing the time-history signals from the excore neutron flux detertors. The conventional method is an on-demand system which generates power spectra through Fast Fourier Transform(FFT) algorithm. The operator can make his own decision to detect abnormal vibration using these spectra. This post- processing method, however, requires special expertise in the reactor noise analysis and signal processing for random data. It may mislead the operator into erroneous decision-making, if he is a novice in reactor noise analysis. Hence this study is focused on the automated monitoring and diagnosis procedure for the reactor noise analysis, especially on the Fuzzy algorithm to recognize the pattern of the vibration of Core Suport Barrel. The excore neutron signals of Yonggwang Nuclear Power Plant unit 3 is acquired and analyzed using conventional FFT spectra and tested to adopt the Fuzzy method. An Automated Monitoring and Diagnosis System for CSB Vibration using this Fuzzy method is proposed. Furthermore, vibration data for CSB of Youggwang Nnclear Power Plant unit 3 is presented.

  • PDF

TCP Performance Enhancement by Implicit Priority Forwarding (IPF) Packet Buffering Scheme for Mobile IP Based Networks

  • Roh, Young-Sup;Hur, Kye-Ong;Eom, Doo-Seop;Lee, Yeon-Woo;Tchah, Kyun-Hyon
    • Journal of Communications and Networks
    • /
    • 제7권3호
    • /
    • pp.367-376
    • /
    • 2005
  • The smooth handoff supported by the route optimization extension to the mobile IP standard protocol should support a packet buffering mechanism at the base station (BS), in order to reduce the degradation in TCP performance caused by packet losses within mobile network environments. The purpose of packet buffering at the BS is to recover the packets dropped during intersubnetwork handoff by forwarding the packets buffered at the previous BS to the new BS. However, when the mobile host moves to a congested BS within a new foreign subnetwork, the buffered packets forwarded by the previous BS are likely to be dropped. This subsequently causes global synchronization to occur, resulting in the degradation of the wireless link in the congested BS, due to the increased congestion caused by the forwarded burst packets. Thus, in this paper, we propose an implicit priority forwarding (IPF) packet buffering scheme as a solution to this problem within mobile IP based networks. In the proposed IPF method, the previous BS implicitly marks the priority packets being used for inter-subnetwork handoff. Moreover, the proposed modified random early detection (M-RED) buffer at the new congested BS guarantees some degree of reliability to the priority packets. The simulation results show that the proposed IPF packet buffering scheme increases the wireless link utilization and, thus, it enhances the TCP throughput performance in the context of various intersubnetwork handoff cases.

Cancer Screening Status in Korea, 2011: Results from the Korean National Cancer Screening Survey

  • Park, Bo-Young;Choi, Kui-Son;Lee, Yoon-Young;Jun, Jae-Kwan;Seo, Hong-Gwan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권4호
    • /
    • pp.1187-1191
    • /
    • 2012
  • This study was conducted to determine the use of screening for stomach, liver, colorectal, breast, and cervical cancers, which are included in the Korean National Cancer Screening Programme. In 2011 the National Cancer Centre in Korea conducted a nationwide, population-based, cross-sectional interview survey using multi-stage random sampling. Participants included 4,100 cancer-free men 40 years and over of age and women over 30 years of age. The lifetime screening rates for stomach, liver, colorectal, breast, and cervical cancers were 76.2%, 54.3%, 56.1%, 79.0%, and, 74.8%, respectively. The rates of recommended screening for stomach, liver, colorectal, breast, and cervical cancers were 64.6%, 22.9%, 35.3%, 60.4%, and 62.4%, respectively. More than 70% of all screening was attributed to organised cancer screening programmes. The main reason given for non attendance was 'no symptoms'. A greater effort is needed to increase screening rates, especially for liver and colorectal cancers.

Aroclor 1254 May Induce Common DNA Effects in Developing Paralichthys olivaceus Embryos and Larvae

  • Min, Eun Young;Kang, Ju Chan
    • Fisheries and Aquatic Sciences
    • /
    • 제17권4호
    • /
    • pp.461-469
    • /
    • 2014
  • Polychlorinated biphenyls (PCBs) are persistent pollutants in aquatic environments, often causing the decline or disappearance of wild populations. In this study, we used a random amplified polymorphic DNA (RAPD) assay to evaluate the effects on the genomic DNA of olive flounder embryo and larval stages of exposure to Aroclor 1254 at concentrations of 1, 5, 10, 20, and $40{\mu}g/L$. We compared RAPD fingerprints of exposed and non-exposed samples. Polymorphisms were revealed as the presence and/or absence of DNA fragments between the two samples. A dose-dependent increase in the number of polymorphic bands was observed with Aroclor 1254 treatment. Also, RAPD profiles of animals exposed to Aroclor 1254 exhibited an increase in the frequency values (FV) compared to the control. A phenogram constructed using neighbor-joining method indicated that genomic template stability in developing embryo and larval stages was significantly affected at ${\geq}5{\mu}g/L$. This study suggested that DNA polymorphisms detected by RAPD analysis could be used as an investigative tool for environmental toxicology and as a useful biomarker in early life stages for the detection of potential genotoxicants.

Efficient Adaptive RED라우터 버퍼 관리 알고리즘 디자인과 구현 (Design and Implementation of Efficient Adaptive RED Router Suffer Management Algorithm)

  • 이종현;임혜영;허의남;황준;김영찬
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (C)
    • /
    • pp.208-210
    • /
    • 2003
  • RED(Random Early Detection) 라우터를 성공적으로 배치하기 위해서는 RED 알고리즘을 구성하는 각 파라미터를 적절히 조절할 수 있어야 한다. 특히 다수의 TCP 연결이 하나의 라우터를 공유하는 네트워크 병목구간에서는 그 중요성이 한층 강조된다. 그러나 RED가 TD 라우터와 같은 네트워크 퍼포먼스를 유지하면서 ICP 커넥션 간 페어니스(fairness)를 향상시키기 위해서는, 네트워크 상황에 따라 다수의 컨트롤 파라미터 값을 적절하게 설정해줘야만 한다. 문제는 다양한 네트워크 환경에서 효과적으로 RED 알고리즘이 동작하기 위해 파라미터를 설정하는 것이 매우 어렵다는 것이다. 본 논문에서는 네트워크 상황에 따라 동적으로 RED 파라미터를 조절하면서 빠르게 안정적인 상태로 적응하는 진보된 RED 알고리즘인 ea-RED(Efficient Adaptive RED)를 디자인하고 구현하여 알고리즘의 효율성을 확인한다.

  • PDF

Prenatal detection of Xq deletion by abnormal noninvasive prenatal screening, subsequently diagnosed by amniocentesis: A case report

  • Kim, Bo Ram;Kim, Rina;Cho, Angela;Kang, Hye Sim;Park, Chul Min;Kim, Sung Yob;Shim, Soon Sup
    • Journal of Genetic Medicine
    • /
    • 제18권2호
    • /
    • pp.117-120
    • /
    • 2021
  • We experienced a case of Xq deletion -- 46,X,del(X)(q22.3) -- detected by abnormal noninvasive prenatal screening, subsequently diagnosed by amniocentesis. Genetic counseling was a challenge because there are few reports of prenatal diagnosis of Xq deletion. In each female cell, one X chromosome is inactivated at random early in development, and there may be a preferential inactivation of the abnormal X chromosome. But some proportions of genes escape inactivation. The most common manifestation in women with Xq deletion is primary or secondary ovarian failure. Critical regions for ovarian function may be located at the long arm of the X chromosome. But, the onset and the severity of ovarian failure may vary with diverse, intricate factors. We anticipate that noninvasive prenatal screening can identify the broader range of chromosomal or genetic abnormalities with the advances in technology and analytic methods. We report our case with a brief review of the literature.

전립선 생검: 일반적 고려사항 및 체계적 생검 (Prostate Biopsy: General Consideration and Systematic Biopsy)

  • 안형우
    • 대한영상의학회지
    • /
    • 제84권6호
    • /
    • pp.1211-1219
    • /
    • 2023
  • 한국은 급속하게 고령화 사회로 진입하고 있으며, 이로 인한 전립선암과 관련된 사회경제적 부담 증가는 불가피하다. 따라서, 전립선암의 조기 발견과 정확한 진단의 필요성은 더욱 높아지고 있다. 일반적으로 이상적인 생검은 최소 숫자의 생검 코어만으로 암을 정확히 찾아낼 수 있어야 한다. 그러나 전립선암은 영상에서 뚜렷한 이상 소견으로 드러나지 않을 수 있기 때문에, 이미지 유도 표적 생검만으로 진단에 충분하지 않다. 따라서 수십 년의 시행착오와 변천을 거쳐, 전립선암 진단은 실질 전반에 대한 무작위적이고 반복적인, 이른바 체계적 생검에 의존하고 있다. 이 종설을 통해 전립선암 진단법의 변천사를 살펴보고, 전립선 생검에 있어 일반적으로 고려해야 할 사항들과 생검 전후의 환자 관리에 대해서 다루고자 한다.

Practice of Breast Self-Examination Among Women in Malaysia

  • Al-Naggar, Redhwan Ahmed;Bobryshev, Yuri V.;Al-Jashamy, Karim
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권8호
    • /
    • pp.3829-3833
    • /
    • 2012
  • Objective: The objective of this study was to examine the practice and associated factors of breast self-examination (BSE) among Malaysian women. Methods: For this cross-sectional study 250 women were selected by a simple random sampling technique. The questionnaire was consisted of three parts: socio-demographic characteristics, knowledge about BSE, and practice of BSE. Obtained data was analyzed using SPSS version 13. T-test and ANOVA test were used to explore the relation between socio-demographic characteristics and the practice of BSE. Results: About 32% of the participants reported that they have had family history of cancer and about 20% of the participants reported that they have had family history of breast cancer. The majority of the participants (88.8%) have heard about breast cancer and 78.4% of the participants have heard about BSE. Race, marital status, residency, regular exercise, awareness about breast cancer, belief that breast cancer can be detected early, belief that early detection improves the chance of survival, family history of cancer, family history of breast cancer, awareness about BSE, and belief that BSE is necessary, significantly influenced the practice of BSE among women. Practice of BSE on monthly basis was found to be 47.2% among the study participants. Conclusions: The socio-demographic characteristics significantly influence the practice of BSA among women in Malaysia. The findings of this study might not only influence the planning of specific screening interventions and strategies in Malaysia but might also be important for the relevant international communities, interested in the peculiarities of BSE incidence in different countries.