• 제목/요약/키워드: interruptions

검색결과 157건 처리시간 0.026초

산림경관 등급화를 위한 평가지표 개발 (Development of Evaluation Indices for Forest Landscape Classification)

  • 강미희;김성일
    • 한국산림과학회지
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    • 제99권6호
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    • pp.777-784
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    • 2010
  • 본 연구는 산림경관의 현재수준을 평가하여 일련의 등급으로 구분하고 각 상황에 부합하는 관리전략을 수립, 실행할 수 있도록 평가지표를 개발하고자 수행되었다. 이를 위해 전문가를 대상으로 심층인터뷰 및 이메일설문조사 등의 정성적, 정량적 연구방법을 적용하여 과학적이며 객관적인 산림경관평가지표를 개발하고자 하였다. 전문가 의견수렴 결과 도출한 최종 산림경관등급화 평가지표는 '생태적 건강성'(녹지자연도, 생태자연도, 병 해충 피해수준, 수관활력도), '경관성'(자연성, 조화성, 다양성, 전통성, 심미성, 희귀성), '민감도'(관광휴양이용수준), '방해요소'(훼손지, 인공구조물) 등의 4개 범주, 총 13개 지표가 선정되었다. 또한 산림경관 평가 등급의 수는 5개로 구분하는 것이 가장 적절한 것으로 조사되었다.

Three Weekly Versus Weekly Cisplatin as Radiosensitizer in Head and Neck Cancer: a Decision Dilemma

  • Negi, Preety;Kingsley, Pamela Alice;Srivastava, Himanshu;Sharma, Surender Kumar
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권4호
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    • pp.1617-1623
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    • 2016
  • Cisplatin-based concurrent chemoradiation plays an undisputed key role as definitive treatment in unresectable patients with locally advanced squamous cell carcinoma head and neck or as an organ preservation strategy. Treatment with 100 mg/m2 3-weekly cisplatin is considered the standard of care but is often associated with several adverse events. The optimum drug schedule of administration remains to be defined and presently, there is insufficient data limiting conclusions about the relative tolerability of one regimen over the other. This review addresses regarding the optimal dose schedule of cisplatin focusing mainly on three-weekly and weekly dose of cisplatin based concurrent chemoradiotherapy in locally advanced head and neck cancer with an emphasis on mucositis, dermatitis, systemic toxicity, compliance, and treatment interruptions. To derive a definitive conclusion, large prospective randomized trials are needed directly comparing standard 3-weekly cisplatin ($100mg/m^2$) with weekly schedule ($30-40mg/m^2$) of concurrent cisplatin based chemoradiotherapy in locally advanced squamous cell carcinoma head and neck.

Static Worst-Case Energy and Lifetime Estimation of Wireless Sensor Networks

  • Liu, Yu;Zhang, Wei;Akkaya, Kemal
    • Journal of Computing Science and Engineering
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    • 제4권2호
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    • pp.128-152
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    • 2010
  • With the advance of computer and communication technologies, wireless sensor networks (WSNs) are increasingly used in many aspects of our daily life. However, since the battery lifetime of WSN nodes is restricted, the WSN lifetime is also limited. Therefore, it is crucial to determine this limited lifetime in advance for preventing service interruptions in critical applications. This paper proposes a feasible static analysis approach to estimating the worstcase lifetime of a WSN. Assuming known routes with a given sensor network topology and SMAC as the underlying MAC protocol, we statically estimate the lifetime of each sensor node with a fixed initial energy budget. These estimations are then compared with the results obtained through simulation which run with the same energy budget on each node. Experimental results of our research on TinyOS applications indicate that our approach can safely and accurately estimate worst-case lifetime of the WSN. To the best of our knowledge, our work is the first one to estimate the worst-case lifetime of WSNs through a static analysis method.

Development of an Intelligent Charger with a Battery Diagnosis Function Using Online Impedance Spectroscopy

  • Nguyen, Thanh-Tuan;Doan, Van-Tuan;Lee, Geun-Hong;Kim, Hyung-Won;Choi, Woojin;Kim, Dae-Wook
    • Journal of Power Electronics
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    • 제16권5호
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    • pp.1981-1989
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    • 2016
  • Battery diagnosis is vital to battery-based applications because it ensures system reliability by avoiding battery failure. This paper presents a novel intelligent battery charger with an online diagnosis function to circumvent interruptions in system operation. The charger operates in normal charging and diagnosing modes. The diagnosis function is performed with the impedance spectroscopy technique, which is achieved by injecting a sinusoidal voltage excitation signal to the battery terminals without the need for additional hardware. The impedance spectrum of the battery is calculated based on voltage excitation and current response with the aid of an embedded digital lock in amplifier in a digital signal processor. The measured impedance data are utilized in the application of the complex nonlinear least squares method to extract the battery parameters of the equivalent circuit. These parameters are then compared with the reference values to reach a diagnosis. A prototype of the proposed charger is applied to four valve-regulated lead-acid batteries to measure AC impedance. The results are discussed.

분산전원 연계 배전계통의 사고 특성 분석 (Analysis of a Fault Characteristics in the Power Network with Distributed Generators)

  • 장성일;박제영;최정환;정종찬;김광호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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    • pp.65-68
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    • 2002
  • Distributed Generators (DG) are rapidly increasing and most of them are interconnected with distribution network to supply power into the network. Therefore, DG may make significant impacts on distribution system operation. protection, and control with respect to the voltage regulation, voltage flicker, harmonics, fault current levels, the losses of the network, etc. These impacts would be demerits for both of DG and distribution networks. And the operation of DG may be influenced by the abnormal grid condition such as disturbances occurred in the neighboring distribution feeders as well as the feeder directly connected with DG. This paper describes the influence of fault occurred in the interconnected power network on the DG operation and the impact of DG on the network load during the interruptions of utility power.

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해수담수화 공정에서 역삼투막의 유기 막오염에 대한 SWRO 막의 화학세정 효율 평가 (Evaluation on Chemical Cleaning Efficiency of Organic-fouled SWRO Membrane in Seawater Desalination Process)

  • 박준영;홍성호;김지훈;정우원;남종우;김영훈;전민정;김형수
    • 상하수도학회지
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    • 제25권2호
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    • pp.177-184
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    • 2011
  • Membrane fouling is an unavoidable phenomenon in operation of seawater reverse osmosis (SWRO) and major obstacle for economic and efficient operation. When fouling occurs on the membrane surface, the permeate flux is decreased, on the contrary, the trans-membrane pressure (TMP) is increased, therefore operation and maintaining costs and potential damage of membranes are able to the pivotal risks of the process. Chemical cleaning process is essential to prevent interruptions for effective RO membrane filtration process. This study focused on proper chemical cleaning condition for polyamide RO membranes of 4 companies. Several chemical agents were applied for chemical cleaning under numbers of operating conditions. Additionally, a monitoring tool of FEEM as autopsy analysis method is adapted for the prediction of organic bio-fouling.

비상시 용수공급을 위한 상수도 연계관로의 수리적 적정성 평가 (Hydraulic Adequacy of Connection Pipes in Water Supply Systems for Contingencies)

  • 한완섭;정관수;김주환
    • 상하수도학회지
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    • 제27권6호
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    • pp.679-687
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    • 2013
  • Although stable and safe drinking water supply to the customers is a basic function of multi-regional water supply systems in Korea, most systems have their vulnerabilities in emergency time due to the branch-type. Application of connections from the other water supply system can provide a solutions for these tentative problems. This paper describes reduction planning of water supply accidents that can minimize a service interruption to customers in multi-regional water supply system by connecting pipe lines between local water supply systems in Mokpo city areas. The result of this study shows that Juam dam multi-regional water supply systems can cover all of the water shortage in southern parts of Jeonnam multi-regional water supply systems by transmitting water through connected pipes between local networks. This can be effective to supply water interactively in various contingencies, when a pipe line accident occurs in southern area of Jeonnam multi-regional water supply systems. On the contrary, southern area of Jeonnam multi-regional water supply systems can cover 99.5 %($62,500m^3/day$) of the water shortage of Juam dam multi-regional water supply systems when service interruptions caused by various pipe accidents occur in the system.

Cardiopulmonary Resuscitation: New Concept

  • Lee, Kwang-Ha
    • Tuberculosis and Respiratory Diseases
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    • 제72권5호
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    • pp.401-408
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    • 2012
  • Cardiopulmonary resuscitation (CPR) is a series of life-saving actions that improve the chances of survival, following cardiac arrest. Successful resuscitation, following cardiac arrest, requires an integrated set of coordinated actions represented by the links in the Chain of Survival. The links include the following: immediate recognition of cardiac arrest and activation of the emergency response system, early CPR with an emphasis on chest compressions, rapid defibrillation, effective advanced life support, and integrated post-cardiac arrest care. The newest development in the CPR guideline is a change in the basic life support sequence of steps from "A-B-C" (Airway, Breathing, Chest compressions) to "C-A-B" (Chest compressions, Airway, Breathing) for adults. Also, "Hands-Only (compression only) CPR" is emphasized for the untrained lay rescuer. On the basis of the strength of the available evidence, there was unanimous support for continuous emphasis on high-quality CPR with compressions of adequate rate and depth, which allows for complete chest recoil, minimizing interruptions in chest compressions and avoiding excessive ventilation. High-quality CPR is the cornerstone of a system of care that can optimize outcomes beyond return of spontaneous circulation (ROSC). There is an increased emphasis on physiologic monitoring to optimize CPR quality, and to detect ROSC. A comprehensive, structured, integrated, multidisciplinary system of care should be implemented in a consistent manner for the treatment of post-cardiac arrest care patients. The return to a prior quality and functional state of health is the ultimate goal of a resuscitation system of care.

Catalytic Biofilms on Structured Packing for the Production of Glycolic Acid

  • Li, Xuan Zhong;Hauer, Bernhard;Rosche, Bettina
    • Journal of Microbiology and Biotechnology
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    • 제23권2호
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    • pp.195-204
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    • 2013
  • While structured packing modules are known to be efficient for surface wetting and gas-liquid exchange in abiotic surface catalysis, this model study explores structured packing as a growth surface for catalytic biofilms. Microbial biofilms have been proposed as selfimmobilized and self-regenerating catalysts for the production of chemicals. A concern is that the complex and dynamic nature of biofilms may cause fluctuations in their catalytic performance over time or may affect process reproducibility. An aerated continuous trickle-bed biofilm reactor system was designed with a 3 L structured packing, liquid recycling and pH control. Pseudomonas diminuta established a biofilm on the stainless steel structured packing with a specific surface area of 500 $m^2m^{-3}$ and catalyzed the oxidation of ethylene glycol to glycolic acid for over two months of continuous operation. A steady-state productivity of up to 1.6 $gl^{-1}h^{-1}$ was achieved at a dilution rate of 0.33 $h^{-1}$. Process reproducibility between three independent runs was excellent, despite process interruptions and activity variations in cultures grown from biofilm effluent cells. The results demonstrate the robustness of a catalytic biofilm on structured packing, despite its dynamic nature. Implementation is recommended for whole-cell processes that require efficient gas-liquid exchange, catalyst retention for continuous operation, or improved catalyst stability.

디지털 컨버전스에서의 인터럽션: 멀티 모달리티와 멀티 태스킹 간의 상호 관계를 중심으로 (Interruption in Digital Convergence: Focused on Multi-Modality and Multi-Tasking)

  • 이기호;정승기;김혜진;이인성;김진우
    • 대한인간공학회지
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    • 제26권3호
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    • pp.67-80
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    • 2007
  • Digital convergence, defined as the creative fusion of once-independent technologies and service, is getting more attention recently. Interruptions among internal functions happen frequently in digital convergence products because many functions that were in separate products are merged into a single product. Multi-tasking and multi-modality are two distinctive features of interruption in digital convergence products, but their impacts to the user have not been investigated yet. This study conducted a controlled experiment to investigate the impacts of multi-tasking and multi-modality on the subjective satisfaction and objective performance of digital convergent products. The study results indicate that multi-tasking and multi-modality have substantial effects individually as well as together. The paper ends with practical and theoretical implications of study results as well as research limits and future research.