• 제목/요약/키워드: rapid loss detection

검색결과 53건 처리시간 0.027초

A Hybrid Active Queue Management for Stability and Fast Adaptation

  • Joo Chang-Hee;Bahk Sae-Woong;Lumetta Steven S.
    • Journal of Communications and Networks
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    • 제8권1호
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    • pp.93-105
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    • 2006
  • The domination of the Internet by TCP-based services has spawned many efforts to provide high network utilization with low loss and delay in a simple and scalable manner. Active queue management (AQM) algorithms attempt to achieve these goals by regulating queues at bottleneck links to provide useful feedback to TCP sources. While many AQM algorithms have been proposed, most suffer from instability, require careful configuration of nonintuitive control parameters, or are not practical because of slow response to dynamic traffic changes. In this paper, we propose a new AQM algorithm, hybrid random early detection (HRED), that combines the more effective elements of recent algorithms with a random early detection (RED) core. HRED maps instantaneous queue length to a drop probability, automatically adjusting the slope and intercept of the mapping function to account for changes in traffic load and to keep queue length within the desired operating range. We demonstrate that straightforward selection of HRED parameters results in stable operation under steady load and rapid adaptation to changes in load. Simulation and implementation tests confirm this stability, and indicate that overall performances of HRED are substantially better than those of earlier AQM algorithms. Finally, HRED control parameters provide several intuitive approaches to trading between required memory, queue stability, and response time.

Fast High-throughput Screening of the H1N1 Virus by Parallel Detection with Multi-channel Microchip Electrophoresis

  • Zhang, Peng;Park, Guenyoung;Kang, Seong Ho
    • Bulletin of the Korean Chemical Society
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    • 제35권4호
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    • pp.1082-1086
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    • 2014
  • A multi-channel microchip electrophoresis (MCME) method with parallel laser-induced fluorescence (LIF) detection was developed for rapid screening of H1N1 virus. The hemagglutinin (HA) and nucleocapsid protein (NP) gene of H1N1 virus were amplified using polymerase chain reaction (PCR). The amplified PCR products of the H1N1 virus DNA (HA, 116 bp and NP, 195 bp) were simultaneously detected within 25 s in three parallel channels using an expanded laser beam and a charge-coupled device camera. The parallel separations were demonstrated using a sieving gel matrix of 0.3% poly(ethylene oxide) ($M_r$ = 8,000,000) in $1{\times}$ TBE buffer (pH 8.4) with a programmed step electric field strength (PSEFS). The method was ~20 times faster than conventional slab gel electrophoresis, without any loss of resolving power or reproducibility. The proposed MCME/PSEFS assay technique provides a simple and accurate method for fast high-throughput screening of infectious virus DNA molecules under 400 bp.

다중 Gigabit Server NICs에서 동적 검출 주기를 적용한 결함 허용 메커니즘 (A Fault Tolerance Mechanism with Dynamic Detection Period in Multiple Gigabit Server NICs)

  • 이진영;이시진
    • 인터넷정보학회논문지
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    • 제3권5호
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    • pp.31-39
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    • 2002
  • 인터넷의 초고속 성장과 멀티미디어 데이터의 급격한 증가로 고속의 전송 매체와 인터페이스 시스템이 요구되고 있다. 이러한 고속의 네트워크 대역폭을 지원하기 위한 대안으로 다중(Multiple) NIC가 개발되고 연구되어 왔다. 다중 NIC를 사용함으로써 기존 네트워크 환경의 큰 변화 없이 고속의 LAN 환경을 구축할 수 있으므로 고성능. 저비용의 효과를 얻을 수 있다. 그러나 대용량 다중 NIC에 SPOF(Singe Point Of Failure) 결함으로 시스템 중단이 생기면, 대용량의 멀티미디어 데이터를 서비스하는 시스템인 만큼 커다란 손실을 가져오게 된다. 따라서 본 논문에서는 결함으로 오는 손실을 방지하기 위해 결함 허용 기법을 사용하여 '결함 허용 다중 NIC'에 대해서 연구한다. 기존의 TMR, Primary-Standby 기법. Watchdog Timer 기법에서 발생되는 자원에 대한 가용성과 내구성의 비효율적인 부분을 고려하여, 동적으로 검출 주기를 변환하여 다운타임을 최소화 할 수 있는 효율적인 결함 허용 메커니즘을 설계하여 제안한다. 결과적으로 본 논문에서 제안한 결함 허용 기법은 결함이 발생하여 생기는 오버헤드 시간을 줄이고자, Fault Detection에서 소요되는 Timeout 시간을 감소시켜 시스템 전반적으로 다운타임을 최소화시킬 수 있다.

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급속한 의식 변화를 초래한 급성 황화수소 중독 1례 (A Case of Acute Hydrogen Sulfide Intoxication Caused Rapid Loss of Consciousness)

  • 안정환;정윤석
    • 대한임상독성학회지
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    • 제2권2호
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    • pp.147-150
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    • 2004
  • Hydrogen sulfide is a colorless, and malodorous 'rotten eggs' gas that results from the decay of organic material. It is a byproduct of industry and agriculture. The mechanism of its toxicity is primarily related to inhibition of oxidative phosphorylation, which causes a decrease in available cellular energy. Because there is no rapid method of detection that is of clinical diagnostic use, management decisions must be made based on history, clinical presentation, and diagnostic tests that imply hydrogen sulfide's presence. Although there is some anecdotal evidence to suggest that the early use of hyperbaric oxygen is beneficial, supportive care remains the mainstay of therapy. We describe an occupational exposure to hydrogen sulfide gas in 51-year-old man. While cleaning the sewage of pigs. he became unconscious. When he arrived in the emergency department, he had irritability and confused mentality. The typical smell of rotten eggs on clothing and exhaled air were enough to be considered to be exposed to hydrogen sulfide. Hyperbaric oxygen therapy was performed. He had a recovery to normal function.

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Rapid Nondestructive Prediction of Multiple Quality Attributes for Different Commercial Meat Cut Types Using Optical System

  • An, Jiangying;Li, Yanlei;Zhang, Chunzhi;Zhang, Dequan
    • 한국축산식품학회지
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    • 제42권4호
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    • pp.655-671
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    • 2022
  • There are differences of spectral characteristics between different types of meat cut, which means the model established using only one type of meat cut for meat quality prediction is not suitable for other meat cut types. A novel portable visible and near-infrared (Vis/NIR) optical system was used to simultaneously predict multiple quality indicators for different commercial meat cut types (silverside, back strap, oyster, fillet, thick flank, and tenderloin) from Small-tailed Han sheep. The correlation coefficients of the calibration set (Rc) and prediction set (Rp) of the optimal prediction models were 0.82 and 0.81 for pH, 0.88 and 0.84 for L*, 0.83 and 0.78 for a*, 0.83 and 0.82 for b*, 0.94 and 0.86 for cooking loss, 0.90 and 0.88 for shear force, 0.84 and 0.83 for protein, 0.93 and 0.83 for fat, 0.92 and 0.87 for moisture contents, respectively. This study demonstrates that Vis/NIR spectroscopy is a promising tool to achieve the predictions of multiple quality parameters for different commercial meat cut types.

레이다 시스템 상호 간 운용을 위한 간섭 보호 기준 분석 (Analysis of Interference Protection Criteria for Interoperability of Radar Systems)

  • 김정;정정수;곽영길;김진국;전용찬
    • 한국전자파학회논문지
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    • 제25권4호
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    • pp.434-441
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    • 2014
  • 최근 군용 레이다 사용이 급증하면서 인접 시스템 상호 간의 전자파 간섭의 영향이 높아지고 있다. 본 논문에서는 레이다의 효율적인 운용을 위하여 국제 표준화 규정에 근거하여 군 무기체계 레이다의 탐지거리 및 탐지확률에 미치는 영향을 분석하여 상호운용에 대한 간섭 보호 기준을 제안한다. 레이다 상호 간 간섭이 존재 할 경우에도 요구 탐지거리 및 탐지확률을 확보하기 위한 허용 INR을 제시하였으며, 특히 INR이 -6 dB인 경우 5 %의 탐지거리 손실을 허용하는 조건에서 최대 탐지확률을 확보하기 위한 SNR을 시뮬레이션을 통하여 결과를 제시하였다. 향후 군 통합무기 체계에서 레이다 상호간의 간섭의 영향에 대한 보호기준을 정립하는데 활용될 것으로 기대한다.

클러스터 정보를 이용한 네트워크 이상상태 탐지방법 (A New Method to Detect Anomalous State of Network using Information of Clusters)

  • 이호섭;박응기;서정택
    • 정보보호학회논문지
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    • 제22권3호
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    • pp.545-552
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    • 2012
  • 최근 우리는 급격한 정보통신 기술의 발달로 큰 변화를 겪었으며, 기존의 기반 시설들 및 서비스들이 정보통신기술과 융합되면서, 다시 한 번 환경 변화를 눈앞에 두고 있다. 정보통신의 발달은 이러한 이점들 외에도 여러 부작용을 낳고 있으며, 이러한 부작용들은 금전적 피해뿐만 아니라 국가적인 재난 상황으로 발전될 소지가 있다. 따라서 이들에 대한 탐지 및 신속한 대응이 중요하며, 이와 관련한 많은 시도가 이루어지고 있다. 이러한 예로는 침입탐지시스템이 있을 수 있다. 그러나 침입탐지시스템은 특정 트래픽이나, 파일이 악성인지 여부를 판단하는데 중점을 두고 있으며, 현재까지 변종이나 새롭게 개발된 악성 코드에 대한 탐지는 힘들다. 따라서 본 논문에서는 네트워크의 현재의 상황과 과거의 상황들을 비교하여, 현재 시점의 네트워크 모델이 정상인지 비정상인지를 판단할 수 있는 방법에 대해 제안한다.

High-Speed Maritime Object Detection Scheme for the Protection of the Aid to Navigation

  • Lee, Hyochan;Song, Hyunhak;Cho, Sungyoon;Kwon, Kiwon;Park, Sunghyun;Im, Taeho
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제16권2호
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    • pp.692-712
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    • 2022
  • Buoys used for Aid to Navigation systems are widely used to guide the sea paths and are powered by batteries, requiring continuous battery replacement. However, since human labor is required to replace the batteries, humans can be exposed to dangerous situation, including even collision with shipping vessels. In addition, Maritime sensors are installed on the route signs, so that these are often damaged by collisions with small and medium-sized ships, resulting in significant financial loss. In order to prevent these accidents, maritime object detection technology is essential to alert ships approaching buoys. Existing studies apply a number of filters to eliminate noise and to detect objects within the sea image. For this process, most studies directly access the pixels and process the images. However, this approach typically takes a long time to process because of its complexity and the requirements of significant amounts of computational power. In an emergent situation, it is important to alarm the vessel's rapid approach to buoys in real time to avoid collisions between vessels and route signs, therefore minimizing computation and speeding up processes are critical operations. Therefore, we propose Fast Connected Component Labeling (FCCL) which can reduce computation to minimize the processing time of filter applications, while maintaining the detection performance of existing methods. The results show that the detection performance of the FCCL is close to 30 FPS - approximately 2-5 times faster, when compared to the existing methods - while the average throughput is the same as existing methods.

단기 기억상실을 주증(主症)으로 하는 6례(例)의 임상보고 -중기(中氣), 건망(健忘), 해리성 기억장애 중심으로 (6 Clinical Reports of Temporary Severe Amnesia Patients -focusing on amnesia, hysteric convulsion, dissociative disorder)

  • 오영진;김보경
    • 동의신경정신과학회지
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    • 제16권2호
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    • pp.287-299
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    • 2005
  • Dissociative disorder is a psychiatric disorder characterized by a sudden loss of memory, but which has no organic disease or explanation. It usually occurs after heavy psychosocial stress or traumatic experience. A transient cerebral ischemic attack (TIA) is an acute episode of temporary and focal loss of cerebral function of vascular origin. TIAs are rapid in onset; symptoms reach their maximal manifestation in fewer than 5 minutes. Manifestations are of variable duration and typically last 2-15 minutes(rarely as long as 24 h). Most TIA durations are less than 1 hour. Of concern is the careful detection of changes in behavior, speech, gait, memory, movement, and vision. TIAs are uncommon in persons younger than 60 years. I treat 6 cases of Sudden Temporary Amnesia Patients with oriental medicine and they are improved. All of them had amnesia for $6{\sim}10\;hours$. During that time, they show behavioral changes and they are not on the state of unconsciousness. After recovery, they also forget what happen at the time. they have some emotional reason too. In conclusion, 4 cases of them belong to dissociative disorder and 2 other cases, TIA.

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rpoS 유전자를 대상으로 하는 Real-Time PCR에 의한 Vibrio vulnificus 검출 (Detection of Vibrio vulnificus by Real-Time PCR targeted to rpoS gene)

  • 김동균;안선희;배주윤;공인수
    • 한국해양바이오학회지
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    • 제2권4호
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    • pp.263-266
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    • 2007
  • Vibrio vulnificusis a causative agent of serious diseases in humans resulting from the contact of wound with seawater or consumption of raw seafood. Several studies aimed at detecting V. vulnificus have targeted vvh as a representative virulence toxin gene belonging to the bacterium. In this study, we targeted the rpoS gene, a general stress regulator, to detect V. vulnificus. PCR specificity was identified by amplification of 8 V. vulnificus templates and by the loss of a PCR product with 36 non-V. vulnificus strains. The PCR assay had the 273-bp fragment and the sensitivity of 10 pg DNA from V. vulnificus. SYBR Green I-based real-time PCR assay targeting the rpoS gene showed a melting temperature of approximately $84^{\circ}C$ for V. vulnificus strains. The minimum level of detection by real-time PCR was 2 pg of purified genomic DNA, or $10^3$ V. vulnificus cells from pure cultured broth and $10^3$ cells in 1g of oyster tissue homogenates. These data indicate that real-time PCR is a sensitive, species-specific, and rapid method for detecting this bacterium using the rpoS gene in pure cultures and in infected oyster tissues.

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