WorldWideScience

Sample records for congestion management evaluation

  1. Framework for Traffic Congestion Management

    OpenAIRE

    Mahmud Hassan TALUKDAR

    2013-01-01

    Traffic Congestion is one of many serious global problems in all great cities resulted from rapid urbanization which always exert negative externalities upon society. The solution of traffic congestion is highly geocentric and due to its heterogeneous nature, curbing congestion is one of the hard tasks for transport planners. It is not possible to suggest unique traffic congestion management framework which could be absolutely applied for every great cities. Conversely, it is quite feasible t...

  2. Framework for Traffic Congestion Management

    Directory of Open Access Journals (Sweden)

    Mahmud Hassan TALUKDAR

    2013-06-01

    Full Text Available Traffic Congestion is one of many serious global problems in all great cities resulted from rapid urbanization which always exert negative externalities upon society. The solution of traffic congestion is highly geocentric and due to its heterogeneous nature, curbing congestion is one of the hard tasks for transport planners. It is not possible to suggest unique traffic congestion management framework which could be absolutely applied for every great cities. Conversely, it is quite feasible to develop a framework which could be used with or without minor adjustment to deal with congestion problem. So, the main aim of this paper is to prepare a traffic congestion mitigation framework which will be useful for urban planners, transport planners, civil engineers, transport policy makers, congestion management researchers who are directly or indirectly involved or willing to involve in the task of traffic congestion management. Literature review is the main source of information of this study. In this paper, firstly, traffic congestion is defined on the theoretical point of view and then the causes of traffic congestion are briefly described. After describing the causes, common management measures, using world- wide, are described and framework for supply side and demand side congestion management measures are prepared.

  3. Disease management 360 degrees: a scorecard approach to evaluating TRICARE's programs for asthma, congestive heart failure, and diabetes.

    Science.gov (United States)

    Yang, Wenya; Dall, Timothy M; Zhang, Yiduo; Hogan, Paul F; Arday, David R; Gantt, Cynthia J

    2010-08-01

    To assess the effect of TRICARE's asthma, congestive heart failure, and diabetes disease management programs using a scorecard approach. EVALUATION MEASURES: Patient healthcare utilization, financial, clinical, and humanistic outcomes. Absolute measures were translated into effect size and incorporated into a scorecard. Actual outcomes for program participants were compared with outcomes predicted in the absence of disease management. The predictive equations were established from regression models based on historical control groups (n = 39,217). Z scores were calculated for the humanistic measures obtained through a mailed survey. Administrative records containing medical claims, patient demographics and characteristics, and program participation status were linked using an encrypted patient identifier (n = 57,489). The study time frame is 1 year prior to program inception through 2 years afterward (October 2005-September 2008). A historical control group was identified with the baseline year starting October 2003 and a 1-year follow-up period starting October 2004. A survey was administered to a subset of participants 6 months after baseline assessment (39% response rate). Within the observation window--24 months for asthma and congestive heart failure, and 15 months for the diabetes program--we observed modest reductions in hospital days and healthcare cost for all 3 programs and reductions in emergency visits for 2 programs. Most clinical outcomes moved in the direction anticipated. The scorecard provided a useful tool to track performance of 3 regional contractors for each of 3 diseases and over time.

  4. Primary and Secondary Congestion Management in Restructured Power Systems

    Directory of Open Access Journals (Sweden)

    Mehdi Hajian

    2015-03-01

    Full Text Available In this paper a new strategy for congestion management is presented. Generally, in congestion management programs all considered contingencies are deterministic or stochastic. Therefore, congestion management cost is increased. In the proposed algorithm, congestion management program is divided to two parts, Primary and Secondary Congestion Management. Also, contingencies are divided in two groups. In the first group, the contingencies that should be managed by preventive actions are considered and the others are taken into account in the second group. The first group of contingencies is in primary congestion management. The secondary congestion management program starts from the nearest time to market run time. So, the secondary congestion management uses corrective actions for managing secondary group contingencies. Also, the secondary congestion management is capable of covering most uncertainties, especially load variations. The proposed method reduces congestion management cost.

  5. Auctionable fixed transmission rights for congestion management

    Science.gov (United States)

    Alomoush, Muwaffaq Irsheid

    Electric power deregulation has proposed a major change to the regulated utility monopoly. The change manifests the main part of engineers' efforts to reshape three components of today's regulated monopoly: generation, distribution and transmission. In this open access deregulated power market, transmission network plays a major role, and transmission congestion is a major problem that requires further consideration especially when inter-zonal/intra-zonal scheme is implemented. Declaring that engineering studies and experience are the criteria to define zonal boundaries or defining a zone based on the fact that a zone is a densely interconnected area (lake) and paths connecting these densely interconnected areas are inter-zonal lines will render insufficient and fuzzy definitions. Moreover, a congestion problem formulation should take into consideration interactions between intra-zonal and inter-zonal flows and their effects on power systems. In this thesis, we introduce a procedure for minimizing the number of adjustments of preferred schedules to alleviate congestion and apply control schemes to minimize interactions between zones. In addition, we give the zone definition a certain criterion based on the Locational Marginal Price (LMP). This concept will be used to define congestion zonal boundaries and to decide whether any zone should be merged with another zone or split into new zones. The thesis presents a unified scheme that combines zonal and FTR schemes to manage congestion. This combined scheme is utilized with LMPs to define zonal boundaries more appropriately. The presented scheme gains the best features of the FTR scheme, which are providing financial certainty, maximizing the efficient use of the system and making users pay for the actual use of congested paths. LMPs may give an indication of the impact of wheeling transactions, and calculations of and comparisons of LMPs with and without wheeling transactions should be adequate criteria to approve

  6. Congestion Management Strategies of Real-Time Market

    DEFF Research Database (Denmark)

    Wang, Qi; Zhang, Chunyu; Ding, Yi

    2014-01-01

    The high penetration of distributed energy resources (DERs) will significantly challenge the power system operation and control due to their stochastic, intermittent, and fluctuation characteristics. This enhances the difficulty of congestion management of power systems in cross-border electricity...... market among different regions. For handling this, the Real-Time Market is proposed for balancing capacity trading against congestions. Several strategies for Real-Time Market dealing with congestions are proposed. The strategy of two-stage crossborder markets in Day-ahead, Intra-day and Real Time Market...... are introduced with the congestion constraints complied. Pre-Contingency strategy is proposed as the advance preparation for the future congestion, and In-Day re-dispatch is used for regulation. Accordingly, the requirements on facilities considering telemetry and remote control in a fast manner are discussed...

  7. Intelligent Management of Highways Congestion based SensorNetworks

    Directory of Open Access Journals (Sweden)

    Guezouli Lyamine

    2012-07-01

    Full Text Available The main purpose of this paper is to enable congestion prediction on urban freeways and objectively measure its impact on daily life. Indeed, cars€™ trafic becomes increasingly difficult and, often causes traffic jams that can last for hours, because of growing number of used cars, in addition to the unforeseen events that may complicate more and more this problem (weather, accidents, road works .... This is mainly due to the lack of efficient management of roads' congestions. This paper attempts to bring a technological response to significantly reduce the congestion problem. Our approach is based on smart sensors which allow traffic jam detecting and relaying such critical information. Thus, while providing the drivers with context aware information such as those related to the highway status before crossing, we enable them to make decision and select another road avoiding the congested one and reducing, by the way, the congestion itself.

  8. Market Based Criteria for Congestion Management and Transmission Pricing

    Directory of Open Access Journals (Sweden)

    Miss. Archana Jaisisngpure

    2014-07-01

    Full Text Available -Congestion Management is one of the major tasks performed by system operator to ensure the operation of transmission system within operating limits. In the emerging electric power market, the congestion management becomes extremely important and it can impose a barrier to the electricity trading. In the present paper, a concept of transmission congestion penalty factors is developed and implemented to control power overflows in transmission lines for congestion management. Here we presents a Re-dispatch methodology for cost of transmission network to its user. The transmission price computation considers the physical impact caused by the market agents in the transmission network. The paper includes case study for IEEE 5 bus power system.

  9. A Hybrid Differential Invasive Weed Algorithm for Congestion Management

    Science.gov (United States)

    Basak, Aniruddha; Pal, Siddharth; Pandi, V. Ravikumar; Panigrahi, B. K.; Das, Swagatam

    This work is dedicated to solve the problem of congestion management in restructured power systems. Nowadays we have open access market which pushes the power system operation to their limits for maximum economic benefits but at the same time making the system more susceptible to congestion. In this regard congestion management is absolutely vital. In this paper we try to remove congestion by generation rescheduling where the cost involved in the rescheduling process is minimized. The proposed algorithm is a hybrid of Invasive Weed Optimization (IWO) and Differential Evolution (DE). The resultant hybrid algorithm was applied on standard IEEE 30 bus system and observed to beat existing algorithms like Simple Bacterial foraging (SBF), Genetic Algorithm (GA), Invasive Weed Optimization (IWO), Differential Evolution (DE) and hybrid algorithms like Hybrid Bacterial Foraging and Differential Evolution (HBFDE) and Adaptive Bacterial Foraging with Nelder Mead (ABFNM).

  10. Congestion management considering voltage security of power systems

    Energy Technology Data Exchange (ETDEWEB)

    Esmaili, Masoud; Shayanfar, Heidar Ali [Centre of Excellence for Power System Automation and Operation, Iran Univ. of Science and Technology, Tehran (Iran); Amjady, Nima [Dept. of Electrical Engineering, Semnan Univ., Semnan (Iran)

    2009-10-15

    Congestion in a power network is turned up due to system operating limits. To relieve congestion in a deregulated power market, the system operator pays to market participants, GENCOs and DISCOs, to alter their active powers considering their bids. After performing congestion management, the network may be operated with a low security level because of hitting some flows their upper limit and some voltages their lower limit. In this paper, a novel congestion management method based on the voltage stability margin sensitivities is introduced. Using the proposed method, the system operator so alleviates the congestion that the network can more retain its security. The proposed method not only makes the system more secure after congestion management than other methods already presented for this purpose but also its cost of providing security is lower than the earlier methods. Test results of the proposed method along with the earlier ones on the New-England test system elaborate the efficiency of the proposed method from the viewpoint of providing a better voltage stability margin and voltage profile as well as a lower security cost. (author)

  11. Dynamic Subsidy Method for Congestion Management in Distribution Networks

    DEFF Research Database (Denmark)

    Huang, Shaojun; Wu, Qiuwei

    2016-01-01

    management in distribution networks, including the market mechanism, the mathematical formulation through a two-level optimization, and the method solving the optimization by tightening the constraints and linearization. Case studies were conducted with a one node system and the Bus 4 distribution network......Dynamic subsidy (DS) is a locational price paid by the distribution system operator (DSO) to its customers in order to shift energy consumption to designated hours and nodes. It is promising for demand side management and congestion management. This paper proposes a new DS method for congestion...... of the Roy Billinton Test System (RBTS) with high penetration of electric vehicles (EVs) and heat pumps (HPs). The case studies demonstrate the efficacy of the DS method for congestion management in distribution networks. Studies in this paper show that the DS method offers the customers a fair opportunity...

  12. Dynamic Subsidy Method for Congestion Management in Distribution Networks

    DEFF Research Database (Denmark)

    Huang, Shaojun; Wu, Qiuwei

    2016-01-01

    Dynamic subsidy (DS) is a locational price paid by the distribution system operator (DSO) to its customers in order to shift energy consumption to designated hours and nodes. It is promising for demand side management and congestion management. This paper proposes a new DS method for congestion...... management in distribution networks, including the market mechanism, the mathematical formulation through a two-level optimization, and the method solving the optimization by tightening the constraints and linearization. Case studies were conducted with a one node system and the Bus 4 distribution network...... of the Roy Billinton Test System (RBTS) with high penetration of electric vehicles (EVs) and heat pumps (HPs). The case studies demonstrate the efficacy of the DS method for congestion management in distribution networks. Studies in this paper show that the DS method offers the customers a fair opportunity...

  13. Evaluation of Congestion Relief Proposals in a Capital City

    Directory of Open Access Journals (Sweden)

    Sudhir C. Fowdur

    2012-01-01

    Full Text Available This paper aims at analyzing three different solutions suggested for traffic congestion relief in Port Louis, the busiest city of Mauritius. It evaluates the impact of the three alternatives which are the use of Light Rail Transit (LRT as an alternative mode of transport, the construction of a Ring road around Port Louis, and the upgrading of the current bus network into a Bus Rapid Transit (BRT system. The impact of these three solutions has been evaluated by performing Traffic Cellular Automata (TCA simulations. Our studies reveal that the Ring road will lead to more congestion while introducing the LRT or upgrading the current bus network will reduce congestion significantly.

  14. A NEW CONGESTION MANAGEMENT MECHANISM FOR NEXT GENERATION ROUTERS

    Directory of Open Access Journals (Sweden)

    MOHAMMED M. KADHUM

    2008-12-01

    Full Text Available While computer networks go towards dealing with varied traffic types with different service requirements, there is a necessity for modern network control mechanisms that can control the network traffic to meet the users' service requirements. Optimizing the network utilization by improving the network performance can help to accommodate more users and thus increase operators’ profits. Controlling the congestion at the gateway leads to better performance of the network. Sending congestion signal sooner can be of great benefit to the TCP connection. In this paper, we propose Fast Congestion Notification (FCN mechanism which is a new method for managing the gateway queues and fast sending of congestion signal to the sender. We tested our mechanism on Explicit Congestion Notification (ECN packets which have higher priority; we achieved good results in terms of faster congestion signal propagation and better network utilization. Our analysis and simulations results show that the use of FCN over TCP connections sharing one bottleneck can improve the throughput, having less loss, less delay time, and better network utilization.

  15. Study and Analysis of Congestion Management in Hybrid Electric Market

    Directory of Open Access Journals (Sweden)

    Moayed Mohseni

    2013-01-01

    Full Text Available The congestion management system is a systematic approach, collaboratively developed and implemented throughout a metropolitan region that provides for the safe and effective management and operation of new and existing transportation facilities through the use of demand reduction and operational management strat­e­gies. In this paper we try to present some points which should be investigated in congestion management problems. We calculate different kinds of congestion problems which may be occurred in our network. Here, the hybrid model is used to solve problems in the electricity market to solve the congestion problem in the network and Benders techniques is used together with an optimal power flow (OPF. In fact, by using of Benders algorithm the problem is divided into two major and minor problems. Therefore, the major problem related to the economy sector and no network is included and the minor problem is to solve the network and examine the accuracy of the network. Benders algorithm has been tested on a standard network IEEE 24 bus and Matlab software is used to implement the algorithm.

  16. Multiobjective Optimization Methods for Congestion Management in Deregulated Power Systems

    Directory of Open Access Journals (Sweden)

    K. Vijayakumar

    2012-01-01

    Full Text Available Congestion management is one of the important functions performed by system operator in deregulated electricity market to ensure secure operation of transmission system. This paper proposes two effective methods for transmission congestion alleviation in deregulated power system. Congestion or overload in transmission networks is alleviated by rescheduling of generators and/or load shedding. The two objectives conflicting in nature (1 transmission line over load and (2 congestion cost are optimized in this paper. The multiobjective fuzzy evolutionary programming (FEP and nondominated sorting genetic algorithm II methods are used to solve this problem. FEP uses the combined advantages of fuzzy and evolutionary programming (EP techniques and gives better unique solution satisfying both objectives, whereas nondominated sorting genetic algorithm (NSGA II gives a set of Pareto-optimal solutions. The methods propose an efficient and reliable algorithm for line overload alleviation due to critical line outages in a deregulated power markets. The quality and usefulness of the algorithm is tested on IEEE 30 bus system.

  17. 23 CFR 971.214 - Federal lands congestion management system (CMS).

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Federal lands congestion management system (CMS). 971... Federal lands congestion management system (CMS). (a) For purposes of this section, congestion means the level at which transportation system performance is no longer acceptable due to traffic...

  18. 23 CFR 970.214 - Federal lands congestion management system (CMS).

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Federal lands congestion management system (CMS). 970....214 Federal lands congestion management system (CMS). (a) For purposes of this section, congestion...) Develop criteria to determine when a CMS is to be implemented for a specific transportation system; and...

  19. 23 CFR 972.214 - Federal lands congestion management system (CMS).

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Federal lands congestion management system (CMS). 972... § 972.214 Federal lands congestion management system (CMS). (a) For purposes of this section, congestion... interference. For those FWS transportation systems that require a CMS, in both metropolitan and...

  20. Coordination strategies for distribution grid congestion management in a Multi-Actor, Multi-Objective Setting

    DEFF Research Database (Denmark)

    Andersen, Peter Bach; Hu, Junjie; Heussen, Kai

    2012-01-01

    and the handling of real-time events for reliable grid operation. This paper presents an analysis of key stakeholders in terms of their objectives and key operations. Three potential strategies for congestion management are presented and evaluated based on their complexity of implementation, the value and benefits...... the interactions between the stakeholders involved, mainly considering the distribution grid congestion problem, and conceptualize several approaches by which their diverse, potentially conflicting, objectives can be coordinated. A key aspect to be considered is the relationship between the operational planning...

  1. Day-Ahead Congestion Management in Distribution Systems through Household Demand Response and Distribution Congestion Prices

    DEFF Research Database (Denmark)

    Liu, Weijia; Wu, Qiuwei; Wen, Fushuan

    2014-01-01

    into balancing power might challenge the operation of electric distribution systems and cause congestions. This paper presents a distribution congestion price (DCP) based market mechanism to alleviate possible distribution system congestions. By employing the loca- tional marginal pricing (LMP) model......, the proposed DCPs are able to reflect the real congestion cost and further direct the schedule of the responses of electric demands. Based on the NordPool Spot market structure, the interactions between aggregators and the distribution system operator (DSO) are discussed, and the procedure for calculating DCPs...

  2. The Congestion Management of Transmission Line using Bacterial Foraging Algorithm

    Directory of Open Access Journals (Sweden)

    Rasul Mokhtarpur

    2012-12-01

    Full Text Available The power systems movement to the electricity industry restructuring circumstance is done with the purpose of deformation of this industry up to elimination of exclusion and fairy competition increment and freely accessing to transmission line. But the possibility of congestion creation in the transmission line could encounter market role makers with problems such as energy price exclusion, difference in energy price at some busses and abusing of some jobbers in the market in these new systems. The study and survey in the interest of prevention and lowering of this phenomenon is done in the name of 'Congestion Management'.In this study after investigation of energy markets and the definition of congestion, local marginal price concept and ordinary method are introduced and then Bacterial Foraging Optimization Algorithm will be investigated in order to optimal determination of Local Marginal Price (LMP in the busses with purpose of production minimizing in pool market and lately it will be tested on a 24-bus standard network to formulate the optimization problem and to make it applicable.

  3. Transmission dispatch and congestion management in open market systems

    Science.gov (United States)

    Fang, Risheng

    This thesis is located in the domain of electricity supply industry restructuring. It deals with emerging issues, whose understanding is essential to advancing knowledge of open access transmission theory and proceeds to develop approaches for solving the transmission dispatch and congestion management problem. An overview of current trends and experiences in utility restructuring and the main models for restructuring, as well as the classifications of system operators, is first presented. A fully unbundled competitive electricity market model, called the bilateral/multilateral trades model, is then developed. A survey of current research in transmission dispatch and congestion management is included with discussion of transmission capacity and ancillary services. A methodology for the power dispatch problem in a structure dominated by bilateral and multilateral transmission contracts is presented. Group structures are mathematically formulated and explored and three basic types of curtailment strategies proposed for use by market participants. A more complex model is then developed, which takes into account the co-existence of bilateral and multilateral contracts with pool type dynamic supplies and demands based on bids and market clearing prices. An integrated dispatch strategy to reconcile all three types of transactions (bilateral, multilateral and pool) is then developed. Prioritization of electricity transactions and related curtailment strategies are explored and a mechanism for coordination between market participants to achieve additional economic advantages is described. A theory of security based rescheduling is presented in order to investigate the security-related aspects of operation in an unbundled and deregulated system. The impact of post-contingency corrective capability on optimal rescheduling results has been identified and the advantage of incorporating post-contingency corrective rescheduling into the objective function demonstrated. Finally

  4. 23 CFR 973.214 - Indian lands congestion management system (CMS).

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Indian lands congestion management system (CMS). 973.214... HIGHWAYS MANAGEMENT SYSTEMS PERTAINING TO THE BUREAU OF INDIAN AFFAIRS AND THE INDIAN RESERVATION ROADS PROGRAM Bureau of Indian Affairs Management Systems § 973.214 Indian lands congestion management...

  5. Performance evaluation of fuzzy and BPN based congestion controller in WSN

    Directory of Open Access Journals (Sweden)

    Rekha Chakravarthi

    2015-04-01

    Full Text Available In a Wireless Sensor Network when an event is detected, the network traffic increases. It in turn increases the flow of data packets and congestion. Congestion in Wireless Sensor Network plays a vital role in degrading the performance of the network. Hence it necessitates, developing a novel technique to control congestion. In this paper, soft computing based congestion control technique is proposed. Fuzzy logic and neural network are the soft computing tools used for estimating the packet drop. The performance of the proposed technique is evaluated using Accuracy. From the results, it is proved that neural network based congestion control technique provides better results than fuzzy based congestion control technique.

  6. Analysis of the algorithms for congestion management in computer networks

    Directory of Open Access Journals (Sweden)

    S. Szilágyi

    2013-06-01

    Full Text Available This paper presents one of the features of DS (Differentiated Services architecture, namely the queuing or congestion management. Packets can be placed into separate buffer queues, on the basis of the DS value. Several forwarding policies can be used to favor high priority packets in different ways. The major reason for queuing is that the router must hold the packet in its memory while the outgoing interface is busy with sending another packet. Our main goal is to compare the performance of the following queuing mechanisms: FIFO (First- In First-Out, CQ (Custom Queuing, PQ (Priority Queuing, WFQ (Weighted Fair Queuing, CBWFQ (Class Based Weighted Fair Queuing and LLQ (Low Latency Queuing.

  7. The Effects of Different Congestion Management Algorithms over Voip Performance

    Directory of Open Access Journals (Sweden)

    Szabolcs Szilágyi

    2015-02-01

    Full Text Available This paper presents one of the features of DS (Differentiated Services architecture, namely the queuing or congestion management. Packets can be placed into separate buffer queues, on the basis of the DS value. Several forwarding policies can be used to favor high priority packets in different ways. The major reason for queuing is that the router must hold the packet in its memory while the outgoing interface is busy with sending another packet. The main goal is to compare the performance of the following queuing mechanisms using a laboratory environment: FIFO (First-In First-Out, CQ (Custom Queuing, PQ (Priority Queuing, WFQ (Weighted Fair Queuing, CBWFQ (Class Based Weighted Fair Queuing and LLQ (Low Latency Queuing. The research is empirical and qualitative, the results are useful both in infocommunication and in education.

  8. Tactical Congestion Management : The Optimal Mix of Decentralized Generators in a District

    NARCIS (Netherlands)

    Croes, N.N.; Phillipson, F; Schreuder, M.H.

    2012-01-01

    A first step in congestion management is making sure that the average production and consumption per time unit over time match as well as possible, we call this tactical congestion management. The main question in this paper is: what is an optimal mix of DGs such that electricity loss is minimized

  9. Collaborative Virtual Queue: Fair Management of Congested Departure Operations and Benefit Analysis

    CERN Document Server

    Burgain, Pierrick; Clarke, John-Paul

    2008-01-01

    Due to the stochastic nature of departure operations, working at full capacity makes major US airports very sensitive to uncertainties. Consequently, airport ground operations face critically congested taxiways and long runway queues. In this report, we show how improved management of departure operations from the ready-to-push-back time to the wheels-off time can potentially yield significant benefits to airlines and air traffic services. We develop a Collaborative Virtual Queue to enable better optimization capabilities during congested situations while taking into account the laissez-faire competitive environment. Results are evaluated using a departure system model, validated using current statistics and previous studies. First, the Collaborative Virtual Queue enables keeping aircraft away from runway queues, which increases wheels-off time predictability. Second, holding aircraft enables last-minute intra-airline flight switching. This creates new optimization capabilities for airlines i.e. it gives airl...

  10. Management of congestion and diuretic resistance in heart failure

    Directory of Open Access Journals (Sweden)

    Giuseppe Regolisti

    2016-11-01

    Full Text Available We present the case of a patient with heart failure and severe congestion who was responding poorly to diuretic therapy. We discuss the key problems concerning the pathophysiology and bedside therapeutic approach to congestion and fluid overload in this clinical setting, and we give practical suggestions to overcome congestion, especially in the setting of diuretic resistance and worsening renal function. We conclude that the application of key pharmacokinetic and pharmacodynamic principles of diuretic therapy, along with in-depth knowledge of the pathophysiology of heart failure, still represent the cornerstones for a correct approach to decongestive therapy in these patients.

  11. Optimal reconfiguration-based dynamic tariff for congestion management and line loss reduction in distribution networks

    DEFF Research Database (Denmark)

    Huang, Shaojun; Wu, Qiuwei; Cheng, Lin

    2016-01-01

    This paper presents an optimal reconfiguration-based dynamic tariff (DT) method for congestion management and line loss reduction in distribution networks with high penetration of electric vehicles. In the proposed DT concept, feeder reconfiguration (FR) is employed through mixed integer programm......This paper presents an optimal reconfiguration-based dynamic tariff (DT) method for congestion management and line loss reduction in distribution networks with high penetration of electric vehicles. In the proposed DT concept, feeder reconfiguration (FR) is employed through mixed integer...... manner through the DT framework. Three case studies were conducted to validate the optimal reconfiguration-based DT method for congestion management and line loss reduction in distribution networks....

  12. Uncertainty Management of Dynamic Tariff Method for Congestion Management in Distribution Networks

    DEFF Research Database (Denmark)

    Huang, Shaojun; Wu, Qiuwei; Cheng, Lin

    2016-01-01

    The dynamic tariff (DT) method is designed for the distribution system operator (DSO) to alleviate congestions that might occur in a distribution network with high penetration of distributed energy resources (DERs). Uncertainty management is required for the decentralized DT method because the DT...

  13. Real-Time Congestion Management in Distribution Networks by Flexible Demand Swap

    DEFF Research Database (Denmark)

    Huang, Shaojun; Wu, Qiuwei

    2017-01-01

    consumption or production. Flexibility service from demand will be a good option to solve the real-time congestions if the cost of activating the flexibility service is fully addressed. This paper proposes a new method, namely “swap”, to employ the flexibility service from electric vehicles (EVs) and heat......In addition to the day-ahead congestion management in distribution networks, the real-time congestion management is very important because many unforeseen events can occur at the real operation time, e.g. loss of generation of distributed energy resources (DERs) or inaccurate forecast of energy...

  14. Extended Queue Management Backward Congestion Control Algorithms for Web Transfers in Wireless Environment

    Directory of Open Access Journals (Sweden)

    V.Sinthu Janita Prakash

    2012-10-01

    Full Text Available Wireless links are characterized by high error rates and intermittent connectivity. TCP congestion control has been developed on the assumption that network congestion is the only cause for packet loss. Upon detecting a packet loss, TCP drops its transmit window resulting in an unnecessary reduction of end-to-end throughput which results in suboptimal performance.The sender has to be made aware by some feedback mechanism that some of the losses reported are not due to congestion. The Active Queue Management algorithms (AQM are used to reduce congestion, and in this paper, we have analysed four AQM algorithms, Random Early Deduction (RED, Wireless Explicit Congestion Notification (WECN, Queue Management Backward Congestion Control Algorithm (QMBCCA and its enhanced version Extended Queue Management Backward Congestion Control Algorithm (EQMBCCA. WECN, QMBCCA & EQMBCCA algorithms make use of feedback mechanisms. WECN gives feedback using the CE bit. QMBCCA and EQMBCCA make use of ISQ notifications and also the CE bit whenever the average queue size crosses minimum threshold value. EQMBCCA reduces the reverse ISQ traffic by introducing a configurable intermediate threshold value IntThres. The comparison is made in terms of Delay, HTTP packet loss percentage and fairness for FTP flows in a wireless environment. It is found that the performance of EQMBCCA is almost equal to that of QMBCCA and better than RED and WECN.

  15. The congestion control algorithm based on queue management of each node in mobile ad hoc networks

    Science.gov (United States)

    Wei, Yifei; Chang, Lin; Wang, Yali; Wang, Gaoping

    2016-12-01

    This paper proposes an active queue management mechanism, considering the node's own ability and its importance in the network to set the queue threshold. As the network load increases, local congestion of mobile ad hoc network may lead to network performance degradation, hot node's energy consumption increase even failure. If small energy nodes congested because of forwarding data packets, then when it is used as the source node will cause a lot of packet loss. This paper proposes an active queue management mechanism, considering the node's own ability and its importance in the network to set the queue threshold. Controlling nodes buffer queue in different levels of congestion area probability by adjusting the upper limits and lower limits, thus nodes can adjust responsibility of forwarding data packets according to their own situation. The proposed algorithm will slow down the send rate hop by hop along the data package transmission direction from congestion node to source node so that to prevent further congestion from the source node. The simulation results show that, the algorithm can better play the data forwarding ability of strong nodes, protect the weak nodes, can effectively alleviate the network congestion situation.

  16. Team management of congestive heart failure across the continuum.

    Science.gov (United States)

    Venner, G H; Seelbinder, J S

    1996-01-01

    Despite an increased incidence of congestive heart failure and frequency of hospital admissions for the Medicare population, there is little information available on improving outcomes for these patients. As changes in health care lead toward capitation, efficient care with limited use of expensive inpatient hospital resources is a necessity. The coordination of three critical components--inpatient, outpatient, and home care--can lead to positive outcomes in terms of functional capacity changes, length of stay, readmission rates, patient self-care knowledge, and patient satisfaction.

  17. Traffic Congestion Evaluation and Signal Control Optimization Based on Wireless Sensor Networks: Model and Algorithms

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2012-01-01

    Full Text Available This paper presents the model and algorithms for traffic flow data monitoring and optimal traffic light control based on wireless sensor networks. Given the scenario that sensor nodes are sparsely deployed along the segments between signalized intersections, an analytical model is built using continuum traffic equation and develops the method to estimate traffic parameter with the scattered sensor data. Based on the traffic data and principle of traffic congestion formation, we introduce the congestion factor which can be used to evaluate the real-time traffic congestion status along the segment and to predict the subcritical state of traffic jams. The result is expected to support the timing phase optimization of traffic light control for the purpose of avoiding traffic congestion before its formation. We simulate the traffic monitoring based on the Mobile Century dataset and analyze the performance of traffic light control on VISSIM platform when congestion factor is introduced into the signal timing optimization model. The simulation result shows that this method can improve the spatial-temporal resolution of traffic data monitoring and evaluate traffic congestion status with high precision. It is helpful to remarkably alleviate urban traffic congestion and decrease the average traffic delays and maximum queue length.

  18. Congestion management of distribution networks with day-ahead dynamic grid tariffs

    DEFF Research Database (Denmark)

    Huang, Shaojun; Wu, Qiuwei

    vehicles (EV) and heat pumps (HP), will be largely deployed in electrical distribution networks. Congestion management will be important in the future active distribution networks. In the IDE4L project, work package 5 is dedicated to develop different kinds of congestion management methods. Demand response......In order to reduce CO2 emissions and alleviate the global warming issue, many countries are setting goals to increase the percentage of renewable energy in the total energy consumption. In this process, a large number of distributed energy resources (DER), distributed generation (DG), electric...... (DR) is one of the important methods. In this report, as one task of work package 5, the day-ahead dynamic tariff (DADT) method for congestion management in distribution networks is presented. The dynamic tariff (DT) can motivate the flexible demands (EV and HP) to shift their energy consumption...

  19. Internet Congestion Control System

    Directory of Open Access Journals (Sweden)

    Pranoto Rusmin

    2010-10-01

    Full Text Available Internet congestion occurs when resource demands exceeds the network capacity. But, it is not the only reason. Congestion can happen on some users because some others user has higher sending rate. Then some users with lower sending rate will experience congestion. This partial congestion is caused by inexactly feedback. At this moment congestion are solved by the involvement of two controlling mechanisms. These mechanisms are flow/congestion control in the TCP source and Active Queue Management (AQM in the router. AQM will provide feedback to the source a kind of indication for the occurrence of the congestion in the router, whereas the source will adapt the sending rate appropriate with the feedback. These mechanisms are not enough to solve internet congestion problem completely. Therefore, this paper will explain internet congestion causes, weakness, and congestion control technique that researchers have been developed. To describe congestion system mechanisms and responses, the system will be simulated by Matlab.

  20. Managing Network Congestion with a Modified Kohonen-based RED Queue

    Directory of Open Access Journals (Sweden)

    Maria Priscilla,

    2010-11-01

    Full Text Available The robustness of today’s Internet depends heavily on the TCP congestion control mechanism. Congestion is a key factor in transmission control protocol (TCP which leads to many researches. Congestion control techniques are extensively used in order to maintain the stability and reliability of the network. One of theimportant issues in the congestion control study is the Queue management technique employed by the network. An exponential increase in network traffic causes increasing packet loss rates. So, the IETF is considering the deployment of active queue management techniques to stem the increasing packet loss rates. Even though the packet loss rates are reduced in the internet by means of active queue management, the prevention of high loss rates is still a major concern for the present techniques. The severity of congestion is indicated by the queue lengths which is the main problem in the present queue management algorithms. Therefore, a fundamentally different active queue management algorithm called Random Early Detection (RED is proposed to overcome the above mentioned problem. BLUE uses packet loss and link idle events to manage congestion. Usingsimulation and controlled experiments, RED is shown to perform significantly better than other techniques both in terms of packet loss rates and buffer size requirements in the network. Then RED approach is combined with Kohonen technique that enables a stable queue length without complex parameters setting and passive measurements. This paper extends the Kohonen RED technique with the modified Kohonen based RED queue technique. It is clearly observed from the experimental results that the proposed approach provides better recognition accuracy with very low training time.

  1. Congestion management in the European electricity market; Engpassmanagement im Europaeischen Strommarkt

    Energy Technology Data Exchange (ETDEWEB)

    Dieckmann, Birgit

    2008-11-24

    The author of the contribution under consideration reports on an assessment of methods of congestion management employed in Europe with respect to their effectiveness and identify possible reasons for the misallocation of cross-border transmission capacity. For this, generation structures of European countries and the resulting prices and load flows are analysed. Different power plants and bottlenecks in the transmission network currently cause structural price differences due to a low degree of integration of European electricity markets. By means of congestion management, the formation of a uniform electricity market will be created.

  2. Review of Congestion Management Methods for Distribution Networks with High Penetration of Distributed Energy Resources

    DEFF Research Database (Denmark)

    Huang, Shaojun; Wu, Qiuwei; Liu, Zhaoxi;

    2014-01-01

    This paper reviews the existing congestion management methods for distribution networks with high penetration of DERs documented in the recent research literatures. The congestion management methods for distribution networks reviewed can be grouped into two categories – market methods and direct...... control methods. The market methods consist of dynamic tariff, distribution capacity market, shadow price and flexible service market. The direct control methods are comprised of network reconfiguration, reactive power control and active power control. Based on the review of the existing methods......, the authors suggest a priority list of the existing methods....

  3. Management of congestive heart failure: a gender gap may still exist. Observations from a contemporary cohort

    Directory of Open Access Journals (Sweden)

    Weller Iris

    2003-02-01

    Full Text Available Abstract Background Unlike other cardiovascular diseases the incidence and prevalence of congestive heart failure (CHF continues to increase. While gender differences in coronary artery disease have been well described, to date, there has been a relative paucity of similar data in patients with CHF. We conducted a pilot study to evaluate the profile and management of patients with CHF at a tertiary care centre to determine if a gender difference exists. Methods A chart review was performed at a tertiary care centre on consecutive patients admitted with a primary diagnosis of CHF between June 1997 and 1998. Co-morbidity, diagnostic investigations, and management of CHF were recorded. Comparisons between male and female patients were conducted. Results One hundred and forty five patients were reviewed. There were 80 male (M and 65 female (F patients of similar age [71.6 vs. 71.3 (M vs. F, p = NS]. Male patients were more likely to have had a previous myocardial infarction (66% vs. 35%, p Conclusions This pilot study demonstrated that there seem to be important gender differences in the profile and management of patients with CHF. Importantly women were less likely to have an evaluation of LV function. As assessment of LV function has significant implications on patient management, this data justifies the need for larger studies to assess gender differences in CHF profile and treatment.

  4. An Auto Tuning Substation Peak Shaving Controller for Congestion Management Using Flexible Demand

    DEFF Research Database (Denmark)

    Sossan, Fabrizio; Marinelli, Mattia

    2013-01-01

    A closed loop substation peak shaving/congestion management controller for radial distribution networks is presented. The controller it uses an individual control signal in order to shift the consumption of a population of demand side resources, DSRs. The controller auto tunes its parameters on...

  5. Congestion management in power systems. Long-term modeling framework and large-scale application

    Energy Technology Data Exchange (ETDEWEB)

    Bertsch, Joachim; Hagspiel, Simeon; Just, Lisa

    2015-06-15

    In liberalized power systems, generation and transmission services are unbundled, but remain tightly interlinked. Congestion management in the transmission network is of crucial importance for the efficiency of these inter-linkages. Different regulatory designs have been suggested, analyzed and followed, such as uniform zonal pricing with redispatch or nodal pricing. However, the literature has either focused on the short-term efficiency of congestion management or specific issues of timing investments. In contrast, this paper presents a generalized and flexible economic modeling framework based on a decomposed inter-temporal equilibrium model including generation, transmission, as well as their inter-linkages. Short and long-term effects of different congestion management designs can hence be analyzed. Specifically, we are able to identify and isolate implicit frictions and sources of inefficiencies in the different regulatory designs, and to provide a comparative analysis including a benchmark against a first-best welfare-optimal result. To demonstrate the applicability of our framework, we calibrate and numerically solve our model for a detailed representation of the Central Western European (CWE) region, consisting of 70 nodes and 174 power lines. Analyzing six different congestion management designs until 2030, we show that compared to the first-best benchmark, i.e., nodal pricing, inefficiencies of up to 4.6% arise. Inefficiencies are mainly driven by the approach of determining cross-border capacities as well as the coordination of transmission system operators' activities.

  6. Simulating producer behavior in congested electricity systems

    NARCIS (Netherlands)

    Van Blijswijk, M.J.; Chappin, E.J.L.; De Vries, L.J.

    2012-01-01

    Congestion management in liberalized power sectors is a complex multi-actor problem, where technical, economic, social, regulatory, and political aspects all play a role. This paper presents a participatory simulation tool that can be used to evaluate congestion management mechanisms. It was develop

  7. FLECH - A Danish market solution for DSO congestion management through DER flexibility services

    DEFF Research Database (Denmark)

    Zhang, Chunyu; Ding, Yi; Nordentoft, Niels Christian

    2014-01-01

    Future electric power systems will face new operational challenges due to the high penetration of distributed energy resources (DERs). In Denmark distribution system operator (DSO) expects a significant congestion increased in distribution grids. In order to manage these congestions and mobilize...... the DERs as economically efficient as possible in the future distribution grid, the brand new notion of Flexibility Clearing House (FLECH) is proposed in this paper. With the Aggregator-based offers, the proposed FLECH market has the ability to promote small scale DERs (up to 5MW) for actively...

  8. Evaluation of the public health impacts of traffic congestion: a health risk assessment

    Directory of Open Access Journals (Sweden)

    Buonocore Jonathan J

    2010-10-01

    Full Text Available Abstract Background Traffic congestion is a significant issue in urban areas in the United States and around the world. Previous analyses have estimated the economic costs of congestion, related to fuel and time wasted, but few have quantified the public health impacts or determined how these impacts compare in magnitude to the economic costs. Moreover, the relative magnitudes of economic and public health impacts of congestion would be expected to vary significantly across urban areas, as a function of road infrastructure, population density, and atmospheric conditions influencing pollutant formation, but this variability has not been explored. Methods In this study, we evaluate the public health impacts of ambient exposures to fine particulate matter (PM2.5 concentrations associated with a business-as-usual scenario of predicted traffic congestion. We evaluate 83 individual urban areas using traffic demand models to estimate the degree of congestion in each area from 2000 to 2030. We link traffic volume and speed data with the MOBILE6 model to characterize emissions of PM2.5 and particle precursors attributable to congestion, and we use a source-receptor matrix to evaluate the impact of these emissions on ambient PM2.5 concentrations. Marginal concentration changes are related to a concentration-response function for mortality, with a value of statistical life approach used to monetize the impacts. Results We estimate that the monetized value of PM2.5-related mortality attributable to congestion in these 83 cities in 2000 was approximately $31 billion (2007 dollars, as compared with a value of time and fuel wasted of $60 billion. In future years, the economic impacts grow (to over $100 billion in 2030 while the public health impacts decrease to $13 billion in 2020 before increasing to $17 billion in 2030, given increasing population and congestion but lower emissions per vehicle. Across cities and years, the public health impacts range from

  9. Evaluation of the public health impacts of traffic congestion: a health risk assessment

    Science.gov (United States)

    2010-01-01

    Background Traffic congestion is a significant issue in urban areas in the United States and around the world. Previous analyses have estimated the economic costs of congestion, related to fuel and time wasted, but few have quantified the public health impacts or determined how these impacts compare in magnitude to the economic costs. Moreover, the relative magnitudes of economic and public health impacts of congestion would be expected to vary significantly across urban areas, as a function of road infrastructure, population density, and atmospheric conditions influencing pollutant formation, but this variability has not been explored. Methods In this study, we evaluate the public health impacts of ambient exposures to fine particulate matter (PM2.5) concentrations associated with a business-as-usual scenario of predicted traffic congestion. We evaluate 83 individual urban areas using traffic demand models to estimate the degree of congestion in each area from 2000 to 2030. We link traffic volume and speed data with the MOBILE6 model to characterize emissions of PM2.5 and particle precursors attributable to congestion, and we use a source-receptor matrix to evaluate the impact of these emissions on ambient PM2.5 concentrations. Marginal concentration changes are related to a concentration-response function for mortality, with a value of statistical life approach used to monetize the impacts. Results We estimate that the monetized value of PM2.5-related mortality attributable to congestion in these 83 cities in 2000 was approximately $31 billion (2007 dollars), as compared with a value of time and fuel wasted of $60 billion. In future years, the economic impacts grow (to over $100 billion in 2030) while the public health impacts decrease to $13 billion in 2020 before increasing to $17 billion in 2030, given increasing population and congestion but lower emissions per vehicle. Across cities and years, the public health impacts range from more than an order of

  10. Transmission Congestion and Voltage Profile Management Using TCSC and TCPAR in Deregulated Power System

    Directory of Open Access Journals (Sweden)

    K.Ragini

    2014-10-01

    Full Text Available In present days all our basic needs are relates with electricity. As the population increases, the demand for electricity is also tremendously increases. In the past, the entire electricity industry is under the control of government and also monopolized. But now, the power industry in many countries is moving rapidly from regulated conventional setup to deregulated environment. The transmission congestion is one of the technical problems that particularly appear in the deregulated power system. If congestion is not managed we face the problems of electricity price improvement and security and stability problems. Congestion relief can be handled using FACTS device such as TCSC, TCPAR where transmission capability will be improved. These FACTS devices are optimally placed on transmission system using Sensitivity approach method. The proposed method is carried out on Modified IEEE-14 bus system and IEEE-24 bus system Using Power World Simulator17 software.

  11. Real Time Emulation of Dynamic Tariff for Congestion Management in Distribution Networks

    DEFF Research Database (Denmark)

    Rasmussen, Theis Bo; Wu, Qiuwei; Huang, Shaojun

    2016-01-01

    This paper presents the real time evaluation of the dynamic tariff (DT) method for alleviating congestion in a distribution networks with high penetration of distributed energy resources (DERs). The DT method is implemented in a real time digital testing platform that emulates a real distribution...

  12. Evaluation of the efficacy of a nurse practitioner-led home-based congestive heart failure clinical pathway.

    Science.gov (United States)

    Moore, Jo-Ann Mary

    2016-01-01

    Frequent exacerbations of symptoms and financial penalties for 30-day hospital readmissions of patients with congestive heart failure (CHF) have led to new disease management approaches. A nurse practitioner (NP)-led interdisciplinary program for CHF management that included home telemonitoring and early NP assessments and interventions was piloted by a home health agency. A 4-month evaluation of the efficacy of a clinical pathway for CHF patients resulted in the enrollment of 22 CHF patients in the program. Two clients were readmitted within 30 days. The new program was effective in reducing 30-day readmission rates to 9% compared to the national average of 23%.

  13. A Self-tuning Fuzzy Queue Management Algorithm for Congestion Control

    Institute of Scientific and Technical Information of China (English)

    Zhang Jingyuan(张敬辕); Xie Jianying

    2004-01-01

    This letter presents an effective self-tuning fuzzy queue management algorithm for congestion control. With the application of the algorithm, routers in IP network regulate its packet drop probability by a self-tuning fuzzy controller. The main advantage of the algorithm is that, with the parameter self-tuning mechanism, queue length can keep stable in a variety of network environments without the difficulty of parameter configuration. Simulations show that the algorithm is efficient, stable and outperforms the popular RED queue management algorithm significantly.

  14. CONGESTION MANAGEMENT BY OPTIMAL ALLOCATION OF FACTS CONTROLLERS USING HYBRID FISH BEE OPTIMIZATION

    Directory of Open Access Journals (Sweden)

    S. Thangalakshmi

    2014-01-01

    Full Text Available The role of Independent System Operator (ISO in the restructured power industry includes system control, capacity planning, transmission tariff and congestion management; the challenging task being minimizing the congestion. One of the popular techniques used to alleviate congestion is using Flexible AC Transmission Systems (FACTS devices. The power system generally operates near its rated capacity in deregulated market because of intensive usage of transmission grids. So, the major issues that need to be addressed are improving the voltage profile and reducing the power loss in the electrical network. Motivation: The location of FACTS devices can improve the power flow in the line, maintain the bus profile and reduce the losses. However locating the ideal location is a NP problem. This study presents a novel heuristic method to determine the types of FACTS devices and its optimal location in a power system without violating the thermal and voltage limits. Power flow sensitivity index to find the optimal location of UPFC is suggested in this study. A hybrid fish bee swarm optimization is proposed which is based on Artificial Bee Colony (ABC and Fish School Search (FSS methods. This proposed algorithm is tested based on IEEE 30 bus system and line performances are studied.

  15. Standardized evaluation of lung congestion during COPD exacerbation better identifies patients at risk of dying

    Directory of Open Access Journals (Sweden)

    Høiseth AD

    2013-12-01

    Full Text Available Arne Didrik Høiseth,1 Torbjørn Omland,1 Bo Daniel Karlsson,2 Pål H Brekke,1 Vidar Søyseth11Cardiothoracic Research Group, Division of Medicine, Akershus University Hospital and Institute of Clinical Medicine, University of Oslo, Oslo, Norway; 2Deptartment of Radiology, Akershus University Hospital, Lørenskog, NorwayBackground: Congestive heart failure is underdiagnosed in patients with chronic obstructive pulmonary disease (COPD. Pulmonary congestion on chest radiograph at admission for acute exacerbation of COPD (AECOPD is associated with an increased risk of mortality. A standardized evaluation of chest radiographs may enhance prognostic accuracy.Purpose: We aimed to evaluate whether a standardized, liberal assessment of pulmonary congestion is superior to the routine assessment in identifying patients at increased risk of long-term mortality, and to investigate the association of heart failure with N-terminal prohormone of brain natriuretic peptide (NT-proBNP concentrations.Material and methods: This was a prospective cohort study of 99 patients admitted for AECOPD. Chest radiographs obtained on admission were routinely evaluated and then later evaluated by blinded investigators using a standardized protocol looking for Kerley B lines, enlarged vessels in the lung apex, perihilar cuffing, peribronchial haze, and interstitial or alveolar edema, defining the presence of pulmonary congestion. Adjusted associations with long-term mortality and NT-proBNP concentration were calculated.Results: The standardized assessment was positive for pulmonary congestion in 32 of the 195 radiographs (16% ruled negative in the routine assessment. The standardized assessment was superior in predicting death during a median follow up of 1.9 years (P=0.022, and in multivariable analysis, only the standardized assessment showed a significant association with mortality (hazard ratio 2.4, 95% confidence interval [CI] 1.2–4.7 (P=0.016 and NT-proBNP (relative

  16. Multilevel Coordination in Smart Grids for Congestion Management of Distribution Grid

    DEFF Research Database (Denmark)

    Hu, Junjie; Lind, Morten; Saleem, Arshad

    2013-01-01

    The operation of the distribution network will change in the near future due to increasing size and number of distributed energy resources (DER) and demand side resources (DSR). An active distribution network is proposed to address the challenges. The normal operation of an active distribution...... network requires coordination of different values and operation constraints of various involved actors. This paper proposes a multilevel coordination strategy for congestion management of distribution network. Firstly, the scheme of an active distribution network is described. Then, the coordination...

  17. Management of air quality in the vicinity of congested area in Kuwait.

    Science.gov (United States)

    Albassam, E; Khan, A; Popov, V

    2009-10-01

    An assessment of air quality in the vicinity of a selected school has been carried out by monitoring the concentrations of primary pollutants. The results has shown that during the school hours, the measured pollutants emitted from the cars next to the selected school, such as CO and NO(2), are always under the allowable limits for Kuwaiti air quality standards. On the other hand, the concentrations of non methane hydrocarbon pollutant (nm-HC), some of which are considered to be cancergenic, are found to be above the Kuwaiti standard most of the times. A traffic counter is used to record the number of cars in the main road next to the school in 15 min intervals for 10 days during the monitoring period for air quality. Statistical analysis is performed to develop a relation for prediction of the necessary reduction in traffic, based on CO concentrations, during morning and afternoon periods on working days. A computer dispersion model (CALINE4) is also used to assess the CO concentrations based on recorded flow of traffic and emission inventory with the prevailing meteorological conditions existed at the specified time. After the validation of model, different scenarios have been evaluated to provide an acceptable solution to resolve the traffic congestion problem near the schools in the early morning hours with substantial reduction in pollution levels. The optimal solution for CO concentration reduction by managing smooth traffic flow is to reduce the traffic intensity by half in early morning and afternoon rush hours. The results of the predicted CO concentration in the vicinity of the school for the model and the statistical analysis has shown reduction of 30% and 42% respectively, for approximately 50% decrease in the car use. On the other hand the predicted CO concentration for the model and the statistics reached 24% and 33% respectively when 50% of students opted for buses instead of using private cars.

  18. Transmission congestion and voltage profile management coordination in competitive electricity markets

    Energy Technology Data Exchange (ETDEWEB)

    Yamin, H.Y. [Yarmouk Univ., Irbid (Jordan). Dept. of Power Engineering; Shahidehpour, S.M. [Illinois Inst. of Technology, Chicago, IL (United States). Dept. of Electrical and Computer Engineering

    2003-12-01

    This paper describes a generalized active/reactive iterative coordination process between GENCOs and the Independent System Operator (ISO) for active (transmission congestion) and reactive (voltage profile) management in the day-ahead market. GENCOs apply priced-based unit commitment without transmission and voltage security constraints, schedule their units and submit their initial bids to the ISO. The ISO executes congestion and voltage profile management for eliminating transmission and voltage profile violations. If violations are not eliminated, the ISO minimizes the transmission and voltage profile violations and sends a signal via the Internet to GENCOs. GENCOs reschedule their units taking into account the ISO signals and submit modified bids to the ISO. The voltage problem is addressed and a linear model is formulated and used in the proposed method. The voltage problem is formulated as a linear programming with a block-angular structure and Dantzig-Wolfe decomposition is applied to generate several smaller problems for a faster and easier solution of large-scale power systems. Two 36 unit GENCOs are used to demonstrate the performance of the proposed generalized active/reactive coordination algorithm. (author)

  19. Evaluation of embolization for periuterine varices involving chronic pelvic pain secondary to pelvic congestion syndrome

    Directory of Open Access Journals (Sweden)

    Flavio Meirelles Siqueira

    Full Text Available OBJECTIVES: To evaluate the clinical response and success rate after periuterine varices embolization in patients with chronic pelvic pain secondary to pelvic congestion syndrome and to report the safety of endovascular treatment and its rate of complications. METHODS: Retrospective cohort of patients undergoing endovascular treatment of pelvic congestion syndrome in our department from January 2012 to November 2015. Data were analyzed based on patient background, imaging findings, embolized veins, rate of complications, and clinical response as indicated by the visual analog pain scale. RESULTS: We performed periuterine varices embolization in 22 patients during the study, four of which required a second embolization. Seventeen patients reported a reduction in pelvic pain after the first embolization and three patients reported a reduction in pelvic pain after the second embolization. Minor complications were observed in our patients, such as postural hypotension, postoperative pain, and venous perforation during the procedure, without clinical repercussion. CONCLUSION: Periuterine varices embolization in patients with chronic pelvic pain secondary to pelvic congestion syndrome appears to be an effective and safe technique.

  20. Never Been KIST: Tor’s Congestion Management Blossoms with Kernel-Informed Socket Transport

    Science.gov (United States)

    2014-08-01

    CUBIC congestion control algorithm. Shadow Topology Enhancements: To ensure that we are causing the most realistic performance and con- gestion effects...selection [13, 59, 60], client throttling [14, 38, 45], circuit scheduling [57], and flow/congestion control [15]. While some of this work has or will be...congestion local to relays running in the public Tor network, and use them to measure congestion from three live relays under our control . Second, we

  1. Congestion management by optimal locating and sizing of TCSC with social welfare maximization in deregulated power markets

    Energy Technology Data Exchange (ETDEWEB)

    Kazemi, A.; Hosseinipoor, N.A. [Iran Univ. of Science and Technology, Tehran (Iran, Islamic Republic of)

    2010-07-01

    A series FACTS device such as a thyristor controlled series compensator (TCSC) has the ability to directly control the power flow and can be effective in improving the operation of a transmission network. This paper examined the optimal locating and sizing of a TCSC, for congestion management in competitive power markets. It proposed an algorithm for congestion management based on an optimal power flow (OPF) framework. The paper discussed the TCSC model and described the proposed method and formulation of an OPF framework. It was solved with the objective function of maximizing the social welfare by using a genetic algorithm for optimal fine-tuning generation and loads schedule and location-sizing of one unit TCSC. The simulation results were tested on the IEEE 14-bus and IEEE 30-bus system. It was validated through comparison of obtained social welfare with and without TCSC. It was concluded that this device was appropriate for long-term congestion management. 12 refs., 5 tabs.

  2. Optimal Bidding Strategy in Power Market before and after Congestion Management Using Invasive Weed Optimization

    Directory of Open Access Journals (Sweden)

    Mohsen Khalilpour

    2013-02-01

    Full Text Available Power companies world-wide have been restructuring their electric power systems from a vertically integrated entity to a deregulated, open-market environment. Previously, electric utilities usually sought to maximize the social welfare of the system with distributional equity as its main operational criterion. The operating paradigm was based on achieving the least-cost system solution while meeting reliability and security margins. This often resulted in investments in generating capacity operating at very low capacity factors. Decommissioning of this type of generating capacity was a natural outcome when the vertically integrated utilities moved over to deregulated market operations. This study proposes an optimizing base and load demand relative binding strategy for generating power apprises of different units in the investigated system. Afterwards, congestion effect in this biding strategy is investigated. The described systems analysis is implemented on 5 and 9 bus systems and optimizing technique in this issue is the Invasive Weed Optimization algorithm; the results are then compared by GA. Finally, examined systems is simulated by using the Power World software; experimental results show that the proposed technique (Invasive Weed Optimization is a high performance by compared GA for the congestion management purposes.

  3. A unified optimization approach for the enhancement of Available Transfer Capability and Congestion Management using unified power flow controller

    Directory of Open Access Journals (Sweden)

    Ramasubramanian Jayashree

    2008-01-01

    Full Text Available This paper proposes a unified optimization model and algorithm for assessing Available Transfer Capability (ATC and carrying out Congestion Management (CM in a Deregulated power system handling both pool and bilateral transactions. It uses a power injection model for Unified Power Flow Controller (UPFC, DC load flow model for power network and repeated linear programming technique for optimization. The DC model enforces the line operating lines in MW. A computer package has been developed and the effectiveness of the proposed unified method has been verified by solving 4 bus and an IEEE 30 bus systems. The results demonstrate the effectiveness of UPFC control on ATC enhancement and Congestion Management.

  4. Improvement of Economic Aspect of Power Network Congestion Management by Swarm Intelligence based Multi-objective Algorithm

    Directory of Open Access Journals (Sweden)

    SANDIP CHANDA,

    2011-05-01

    Full Text Available This paper presents a methodology based on a rescheduling algorithm for congestion constrained cost optimization in Particle Swarm Optimization environment. For proper maintenance of security and reliability, the congestion level of lines should be restricted to a stipulated value considering stability and demand constraints. The algorithm, proposed in this paper is capable of limiting line congestion with a minimum management charge without any load curtailment and installation of FACTS devices and it also provides better operating conditions in respect of voltage profile, total line loss and security for the system during contingency. For contingency selection and ranking, a Line Loading Index has also been proposed in this paper. A comparative analysis considering conventional cost optimization has also been presented in this paper which shows the applicability of the algorithm to minimize congestion management cost .It has also been shown that the implementation of the proposed methodology can offer a net saving of congestion cost which may appear as social welfare for the market participants. The proposed algorithm has been shown to be tested on IEEE 30 bus test system and the results obtained, looked promising.

  5. Congestion in the bathtub

    DEFF Research Database (Denmark)

    Fosgerau, Mogens

    2015-01-01

    This paper presents a model of urban traffic congestion that allows for hypercongestion. Hypercongestion has fundamental importance for the costs of congestion and the effect of policies such as road pricing, transit provision and traffic management, treated in the paper. In the simplest version ...

  6. Congestion in the bathtub

    DEFF Research Database (Denmark)

    Fosgerau, Mogens

    2015-01-01

    This paper presents a model of urban traffic congestion that allows for hypercongestion. Hypercongestion has fundamental importance for the costs of congestion and the effect of policies such as road pricing, transit provision and traffic management, treated in the paper. In the simplest version...

  7. ANALYSIS OF LINK STATE RESOURCE RESERVATION PROTOCOL FOR CONGESTION MANAGEMENT IN SMART WEB HOTSPOT ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    Anulika Okoye Joy1

    2016-06-01

    Full Text Available With the wide spread of WiFi hotspots, concentrated traffic workload on Smart Web (SW can slow down the network performance. This paper presents a congestion management strategy considering real time activities in today’s smart web. With the SW context, cooperative packet recovery using resource reservation procedure for TCP flows was adapted for mitigating packet losses. This is to maintain data consistency between various access points of smart web hotspot. Using a real world scenario, it was confirmed that generic TCP cannot handle traffic congestion in a SW hotspot network. With TCP in scalable workload environments, continuous packet drops at the event of congestion remains obvious. This is unacceptable for mission critical domains. An enhanced Link State Resource Reservation Protocol (LSRSVP which serves as dynamic feedback mechanism in smart web hotspots is presented. The contextual behaviour was contrasted with the generic TCP model. For the LS-RSVP, a simulation experiment for TCP connection between servers at the remote core layer and the access layer was carried out while using selected benchmark metrics. From the results, under realistic workloads, a steady-state throughput response was achieved by TCP LS-RSVP to about 3650Bits/secs compared with generic TCP plots in a previous study. Considering network service availability, this was found to be dependent on fault-tolerance of the hotspot network. From study, a high peak threshold of 0.009 (i.e. 90% was observed. This shows fairly acceptable service availability behaviour compared with the existing TCP schemes. For packet drop effects, an analysis on the network behaviour with respect to the LS-RSVP yielded a drop response of about 0.000106 bits/sec which is much lower compared with the case with generic TCP with over 0.38 bits/sec. The latency profile of average FTP download response was found to be 0.030secs, but with that of FTP pload response, this yielded about 0.028 sec. The

  8. A Cooperative Congestion Control Approach within VANETs: Formal Verification and Performance Evaluation

    OpenAIRE

    Bouassida MohamedSalah; Shawky M

    2010-01-01

    The main objective of congestion control is to best exploit the available network resources while preventing sustained overloads of network nodes and links. Appropriate congestion control mechanisms are essential to provide effcient operation of a network. Ensuring congestion control within vehicular ad hoc networks faces special challenges, due to the specificities of such environment (High mobility of nodes, high rate of topology changes, high variability in nodes density and neighborhood ...

  9. Echocardiographic evaluation of cardiac dyssynchrony in patients with congestive heart failure.

    Science.gov (United States)

    Qin, Chuan; Zhang, Li; Zhang, Zi-Ming; Wang, Bin; Ye, Zhou; Wang, Yong; Nanda, Navin C; Xie, Ming-Xing

    2016-06-01

    The present study investigated the application of echocardiography to evaluation of cardiac dyssynchrony in patients with congestive heart failure (CHF). A total of 348 consecutive CHF patients who were admitted for cardiac resynchronization (CRT) and presented with low ejection fraction (EF) and wide QRS duration were enrolled in this study, along with 388 healthy individuals. Dyssynchrony was assessed based on filling time ratio (FT/RR), left ventricular pre-ejection delay (PED), interventricular mechanical delay (IVMD), longitudinal opposing wall delay (LOWD) and radial septal to posterior wall delay (RSPWD). Response to CRT was defined as a ≥15% increase in EF. The results showed that FT/RR was decreased while PED, IVMD, LOWD and RSPWD were increased in the CHF group compared with the control group (Pcardiac dyssynchrony in patients with CHF.

  10. Predictive functional control for active queue management in congested TCP/IP networks.

    Science.gov (United States)

    Bigdeli, N; Haeri, M

    2009-01-01

    Predictive functional control (PFC) as a new active queue management (AQM) method in dynamic TCP networks supporting explicit congestion notification (ECN) is proposed. The ability of the controller in handling system delay along with its simplicity and low computational load makes PFC a privileged AQM method in the high speed networks. Besides, considering the disturbance term (which represents model/process mismatches, external disturbances, and existing noise) in the control formulation adds some level of robustness into the PFC-AQM controller. This is an important and desired property in the control of dynamically-varying computer networks. In this paper, the controller is designed based on a small signal linearized fluid-flow model of the TCP/AQM networks. Then, closed-loop transfer function representation of the system is derived to analyze the robustness with respect to the network and controller parameters. The analytical as well as the packet-level ns-2 simulation results show the out-performance of the developed controller for both queue regulation and resource utilization. Fast response, low queue fluctuations (and consequently low delay jitter), high link utilization, good disturbance rejection, scalability, and low packet marking probability are other features of the developed method with respect to other well-known AQM methods such as RED, PI, and REM which are also simulated for comparison.

  11. FACTS Devices Cost Recovery During Congestion Management in Deregulated Electricity Markets

    Science.gov (United States)

    Sharma, Ashwani Kumar; Mittapalli, Ram Kumar; Pal, Yash

    2016-09-01

    In future electricity markets, flexible alternating current transmission system (FACTS) devices will play key role for providing ancillary services. Since huge cost is involved for the FACTS devices placement in the power system, the cost invested has to be recovered in their life time for the replacement of these devices. The FACTS devices in future electricity markets can act as an ancillary services provider and have to be remunerated. The main contributions of the paper are: (1) investment recovery of FACTS devices during congestion management such as static VAR compensator and unified power flow controller along with thyristor controlled series compensator using non-linear bid curves, (2) the impact of ZIP load model on the FACTS cost recovery of the devices, (3) the comparison of results obtained without ZIP load model for both pool and hybrid market model, (4) secure bilateral transactions incorporation in hybrid market model. An optimal power flow based approach has been developed for maximizing social welfare including FACTS devices cost. The optimal placement of the FACTS devices have been obtained based on maximum social welfare. The results have been obtained for both pool and hybrid electricity market for IEEE 24-bus RTS.

  12. Power Trading and Congestion Management Through Real Power Rescheduling Using Unified Power Flow Controller

    Directory of Open Access Journals (Sweden)

    S.K. Gupta

    2014-09-01

    Full Text Available Congestion is termed as the operating condition in which there is not enough transmission capacity to implement all the desired transactions. This paper deals with the power trading in electricity market to ensure regular supply at competitive rates. Bidding process of 75 Indian bus systems is analyzed. It is shown that how can congestion cost can be addressed through active power rescheduling with transmission line constraints using Unified power flow controller.

  13. Design, Implementation and Evaluation of Congestion Control Mechanism for Video Streaming

    Directory of Open Access Journals (Sweden)

    Hiroshi Noborio

    2011-05-01

    Full Text Available In recent years, video streaming services over TCP, such as YouTube, have become more and more popular. TCP NewReno, the current TCP standard, performs greedy congestion control, which increases the congestion window size until packet loss occurs. Therefore, because TCP transmits data at a much higher rate than the video playback rate, the probability of packet loss in the network increases, which in turn takes bandwidth from other network traffic. In this paper, we propose a new transport-layer protocol, called TCP Stream, that solves the problem of TCP in video streaming. TCP Stream performs a hybrid congestion control that combines the loss-based congestion control, which uses packet loss as an index of congestion, and the delay-based congestion control, which uses delay as an index of congestion. Simulation and experimental results show that TCP Stream transmits data at the adjusted rate, unlike TCP NewReno, and does not steal bandwidth from of other network traffic.

  14. 基于Fuzzy—PCA的城市区域交通拥挤评价方法%Regional traffic congestion evaluation based on Fuzzy-PCA

    Institute of Scientific and Technical Information of China (English)

    刘海青; 杨立才; 吴磊; 孔璐璐

    2012-01-01

    Urban regional traffic congestion evaluation is the basis for regional traffic management and traffic guidance. To give a quantitative evaluation for the regional traffic congestion, a method based on principal component analysis and fuzzy comprehensive evaluation was proposed. Regarding average travel time as the indicators of traffic congestion, and road sections as influence factors in this method, the influence weight was established by using the method of principal component analysis, and regional traffic congestion was evaluated based on fuzzy comprehensive evaluation. Taking the actual traffic network structure of Jinan for an example, an experiment was given to illustrate the method by using of the traffic simulation software VISSIM and the statistical analysis software SPSS. Results showed that the method could describe urban regional traffic congestion objectively and effectively.%城市区域路网交通状态分析是实施区域交通管理和交通诱导的基础。为实现对区域路网拥挤状况的有效刻画,提出了一种基于主成分分析和模糊综合评价相结合的定量评价方法。以路段平均行程时间为描述交通拥挤的参数,将路网中所包含的各个路段作为影响因素,利用主成分分析法确立了各个路段对区域拥挤的影响权重;运用模糊综合评价法对区域路网拥挤状况进行了评估。在济南市实际路网结构下,通过VISSIM交通仿真软件和SPSS数据统计分析软件对算法进行了实例验证。结果表明,该算法能够客观、有效地刻画城市区域道路的交通拥挤状况。

  15. 23 CFR 450.320 - Congestion management process in transportation management areas.

    Science.gov (United States)

    2010-04-01

    ... management process should result in multimodal system performance measures and strategies that can be reflected in the metropolitan transportation plan and the TIP. The level of system performance deemed... effective integrated management and operation of the multimodal transportation system, based on a...

  16. Evaluation of advanced congestion control mechanisms for unreliable CoAP communications

    OpenAIRE

    Betzler, August; Gómez Montenegro, Carlos; Seyfettin Demirkol, Ilker

    2015-01-01

    Networks of constrained devices play an important role in the Internet of Things (IoT). In such networks congestion may lead to significant performance decrease and is a recurring phenomenon given the restricted hardware capacities of constrained devices and the limitations of low-power radios. The Constrained Application Protocol (CoAP) designed for IoT communications defines a basic congestion control mechanism for the exchange of messages with end-to-end reliability between two endpo...

  17. Mediastinal lymphadenopathy in congestive heart failure: a sequential CT evaluation with clinical and echocardiographic correlations

    Energy Technology Data Exchange (ETDEWEB)

    Chabbert, Valerie; Canevet, Guillaume; Otal, Philippe; Joffre, Francis [Department of Radiology, University of Toulouse, Avenue Jean-Poulhes, 31403, Toulouse (France); Baixas, Cecile; Galinier, Michel [Department of Cardiology, University of Toulouse, Avenue Jean-Poulhes, 31403, Toulouse (France); Deken, Valerie; Duhamel, Alain [Department of Medical Statistics, University of Lille, Place de Verdun, 59037, Lille Cedex (France); Remy, Jacques; Remy-Jardin, Martine [Department of Radiology, Hospital Calmette, University Center of Lille, Boulevard Jules Leclerc, 59037, Lille Cedex (France)

    2004-05-01

    The aim of this study was to evaluate the frequency and evolution after treatment of mediastinal lymphadenopathy associated with congestive left heart failure on CT scans in correlation with clinical and echocardiographic findings. Thirty-one consecutive patients with subacute left heart failure underwent a clinical evaluation using the NYHA classification, a CT examination, and transthoracic echocardiography at the time of initial presentation (T1). After initiation of medical treatment (T2), follow-up CT scans were systematically obtained together with a clinical evaluation. At T1, all patients showed severe (type III: n=12, 39%; type IV: n=12, 39%) to moderate (type I, n=1, 3%; type II, n=6, 19%) dyspnea with a mean ejection fraction of 39% (range 22-74%). On initial CT scans, enlarged mediastinal lymph nodes were seen in 13 patients (42%) with blurred contours in 5 patients (16%) and hazy mediastinal fat in 1 patient (3%). Significant decrease in the size of lymphadenopathy was observed between T1 and T2 (T1, n=13, 42% vs T2, n=10, 32%; p<0.05) with a concurrent decrease in the severity of dyspnea (grade III-IV dyspnea at T1, n=24, 78% vs grade I-II dyspnea at T2, n=26, 83.5%). Patients with enlarged lymph nodes at T1 showed: (a) a significantly lower ejection fraction at echocardiography than those without lymphadenopathy (mean{+-}SD value: 34{+-}12.9 vs 43{+-}13.8%; p=0.04); (b) a significantly larger diameter of the right superior pulmonary vein (mean{+-}SD value: 17{+-}2.75 vs 14{+-}3.9 mm; p=0.04); and (c) a higher frequency of abnormal peribronchovascular thickening (n=5 vs n=1; p=0.06). Mediastinal lymphadenopathy associated with subacute left heart failure was observed in 13 patients (42%), showing regression after initiation of treatment in 8 of 13 patients (62%). (orig.)

  18. Managing truck arrivals with time windows to alleviate gate congestion at container terminals

    DEFF Research Database (Denmark)

    Chen, G.; Govindan, Kannan; Yang, Z.

    2013-01-01

    Long truck queues at gates often limit the efficiency of a container terminal and generate serious air pollution. To reduce the gate congestion, this paper proposes a method called'vessel dependent time windows (VDTWs)' to control truck arrivals, which involves partitioning truck entries into gro......Long truck queues at gates often limit the efficiency of a container terminal and generate serious air pollution. To reduce the gate congestion, this paper proposes a method called'vessel dependent time windows (VDTWs)' to control truck arrivals, which involves partitioning truck entries...... in the system. A conventional Genetic Algorithm (GA), a multi-society GA, and a hybrid algorithm using GA and Simulated Annealing are used to solve the optimization problem. A case study based on a real container terminal in China is performed, which shows the VDTWs method can flatten the truck arrivals...

  19. Congestion management rules and trading strategies in the Spanish electricity market

    Energy Technology Data Exchange (ETDEWEB)

    Furio, Dolores; Lucia, Julio J. [Departamento de Economia Financiera y Actuarial, Universidad de Valencia, Avda. Los Naranjos, s/n, 46022 - Valencia (Spain)

    2009-01-15

    This paper analyses the economic incentives embodied in the rules governing the resolution of transmission constraints in the Spanish wholesale electricity market and the way these incentives may have influenced on the trading behaviour of both the generators and the demand side. The evidence obtained is consistent with them responding to these incentives. In particular, buyers would respond to the way congestion costs are billed to them by abandoning the daily market in favour of the intraday market as far as possible. Additionally, some strategic generators may have been prompted the system operator to require them to inject electricity into the system to solve network congestions. Finally, these results may contribute to shed light on what should be expected of the reform in the aforementioned rules. (author)

  20. CONGESTION MANAGEMENT IN DEREGULATED POWER SYSTEMS USING REAL CODED GENETIC ALGORITHM

    Directory of Open Access Journals (Sweden)

    Sujatha Balaraman

    2010-11-01

    Full Text Available In this paper, an efficient method has been proposed for transmission line over load alleviation in deregulated power system using real coded genetic algorithm (RCGA. For secure operation of power system, the network loading has to be maintained within specified limits. Transmission line congestion initiates the cascading outages which forces the system to collapse. Accurate prediction and alleviation of line overloads is the suitable corrective action to avoid network collapse. In this paper an attempt is made to explore the use of real coded genetic algorithm to find the optimal generation rescheduling for relieving congestion. The effectiveness of the proposed algorithm has been analyzed on IEEE 30 bus test system. The results obtained by the proposed method are found to be quite encouraging when compared with Simulated Annealing (SA and hence it will be useful in electrical restructuring.

  1. Distribution Locational Marginal Pricing through Quadratic Programming for Congestion Management in Distribution Networks

    DEFF Research Database (Denmark)

    Huang, Shaojun; Wu, Qiuwei; Oren, Shmuel S.

    2015-01-01

    This paper presents the distribution locational mar- ginal pricing (DLMP) method through quadratic programming (QP) designed to alleviate the congestion that might occur in a distribution network with high penetration of flexible demands. In the DLMP method, the distribution system operator (DSO...... ensure that the central- ized DSO optimization and the decentralized aggregator optimi- zation converge. Case studies using a distribution network with high penetration of electric vehicles (EVs) and heat pumps (HPs) validate the equivalence of the two optimization setups, and the efficacy...

  2. Traffic Congestion and Congestion Pricing

    OpenAIRE

    Verhoef, E.T.; Lindsey, C.R.

    2000-01-01

    For several decades growth of traffic volumes has outstrippedinvestments inroad infrastructure. The result has been a relentless increase intrafficcongestion. This paper reviews the economic principles behindcongestionpricing in static and dynamic settings, which derive from thebenefits ofcharging travellers for the externalities they create. Specialattention ispaid to various complications that make simple textbook congestionpricingmodels of limited relevance, and dictate that congestion pri...

  3. Multi Objective Genetic Algorithm for Congestion Management in Deregulated Power System Using Generator Rescheduling and Facts Devices

    Directory of Open Access Journals (Sweden)

    S. Sivakumar

    2014-10-01

    Full Text Available The problem of congestion management is more pronounced in deregulated environment as the participants of the energy market are market oriented rather than socially responsible-as exhibited by the government operated bundled system. Customers would like to purchase the electricity from the cheapest available sources. The seller in energy market would like to derive more benefit out of their investments, engages with contracts that may lead to overloading of the transmission elements of the power system. An Independent System Operator (ISO who has no vested interest in the energy market, coordinates the trades and make sure that the interconnected power system always operates in a secure state at a minimum cost by meeting the all the load requirements and losses. In this proposed study, Congestion is mitigated by Generator Rescheduling and implementation of FACTS devices. Minimization of rescheduling costs of the generator and minimization of the cost of deploying FACTS devices are taken as the objectives of the given multi-objective optimization problem. Non-dominated sorting genetic algorithm II is used to solve this problem by implementing the series FACTS device namely TCSC and shunt FACTS device namely SVC. The proposed algorithm is tested on IEEE 30 bus system.

  4. Optimal Rescheduling of Generators for Congestion Management and Benefit Maximization in a Decentralized Bilateral Multi-transactions Power Network

    Science.gov (United States)

    Singh, Brijesh; Mahanty, Ranjit; Singh, S. P.

    2013-05-01

    This paper presents a framework to achieve an optimal power flow solution in a decentralized bilateral multitransaction-based market. An independent optimal dispatch solution has been used for each market. The interior point (IP)-based optimization technique has been used for finding a global economic optimal solution of the whole system. In this method, all the participants try to maximize their own profits with the help of system information announced by the operator. In the present work, a parallel algorithm has been used to find out a global optimum solution in decentralized market model. The study has been carried out on a modified IEEE-30 bus system. The results show that the suggested decentralized approach can provide a better optimal solution. The obtained results show the effectiveness of IP optimization-based optimal generator schedule and congestion management in the decentralized market.

  5. Controlling Congestion on Complex Networks

    CERN Document Server

    Buzna, Lubos

    2016-01-01

    From the Internet to road networks and the power grid, modern life depends on controlling flows on critical infrastructure networks that often operate in a congested state. Yet, we have a limited understanding of the relative performance of the control mechanisms available to manage congestion and of the interplay between network topology, path layout and congestion control algorithms. Here, we consider two flow algorithms (max-flow and uniform-flow), and two more realistic congestion control schemes (max-min fairness and proportional fairness). We analyse how the algorithms and network topology affect throughput, fairness and the location of bottleneck edges. Our results show that on large random networks a network operator can implement the trade-off (proportional fairness) instead of the fair allocation (max-min fairness) with little sacrifice in throughput. We illustrate how the previously studied uniform-flow approach leaves networks severely underutilised in comparison with congestion control algorithms...

  6. Performance evaluation on IEEE 802.11e considering emergency calls in congested situation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    To enhance the quality of service (QoS) support in IEE 802.11, IEEE 802.11e has been studied, which introduces the so-called hybrid coordination function (HCF). HCF includes two medium access mechanisms: contention-based channel access (EDCA), and contention-free channel access (HCCA). Although IEEE 802.11e has provided differentiated channel access mechanism, when call demand rises for important festivals such as New Year's Day or large scale natural disasters such as earthquakes, the delay of voice will increase and the QoS of voice nodes will drop down rapidly. Through our simulation study, in order to guarantee the QoS of emergency voice calls in congested situation, a higher priority for these calls will be required.

  7. Occurrence, aetiology and challenges in the management of congestive heart failure in sub-saharan Africa: experience of the Cardiac Centre in Shisong, Cameroon

    Directory of Open Access Journals (Sweden)

    Tantchou Tchoumi Jacques Cabral

    2011-02-01

    Full Text Available INTRODUCTION: The aim of the study was to investigate the occurrence, the aetiology and the management of congestive heart failure in the cardiac centre of the St. Elizabeth catholic general hospital Shisong in Cameroon. METHODS: Between November 2002 and November 2008, a population of 8121 patients was consulted in the referral cardiac centre of St. Elizabeth Catholic General Hospital. Of these patients, 462 were diagnosed with congestive heart failure according to the modified Framingham criteria for the diagnosis of heart failure. Complementary investigations used to confirm and establish the aetiology of the disease were the chest X-ray, electrocardiography, bi-dimensional Doppler echocardiography. RESULTS: The results showed that the occurrence of congestive heart failure in our centre was 5,7%. Congestive heart failure was diagnosed in 198 females and 264 males, aged between 8 and 86 years old (42.5, plus or minus 18 years old. Post rheumatic valvulopathies (14.6% and congenital heart diseases (1.9% were the first aetiologic factor of congestive heart failure in the young, meanwhile cardiomyopathies (8,3% in elderly followed by hypertensive cardiomyopathy (4.4%. Congestive heart failure was also seen in adults with congenital heart diseases in 0.01%. In this zone of Cameroon, we discovered that HIV cardiomyopathy (1.6% and Cor pulmonale (8% were represented, aetiological factors not mentioned in previous studies conducted in urban areas of Cameroon. The mean duration of hospital stay for the compensation treatment was thirteen days, ranging between 7 and 21 days, the mortality being 9.2%. All the medications recommended for the treatment of congestive heart failure are available in our centre but many patients are not compliant to the therapy or cannot afford them. Financial limitation is causing the exacerbation of the disease and premature death. CONCLUSION: Our data show a high incidence of congestive heart failure mainly due to post

  8. The potential role of calcium antagonists in the management of congestive heart failure : Initial experience with lacidipine

    NARCIS (Netherlands)

    deVries, RJM; Dunselman, PHJM

    1995-01-01

    First-generation calcium antagonists have been used in patients with congestive heart failure with rather disappointing results. Therefore, second-generation dihydropyridine calcium-channel blockers, such as felodipine and lacidipine, have been developed that may be beneficial in congestive heart fa

  9. Experimental Evaluation of Memory Effects on TCP Traffic in Congested Networks

    Directory of Open Access Journals (Sweden)

    Kulvinder Singh

    2010-09-01

    Full Text Available Today the Internet is a worldwide-interconnected computer network that transmits data by packet switching based on the TCP/IP protocol suite. Internet has TCP as the main protocol of the transport layer. The performance of TCP is studied by many researchers. They are trying to analytically characterizing the throughput of TCP's congestion control mechanism. Internet routers were widely believed to need big memory spaces. Commercial routers today have huge packet memory spaces, often storing millions of packets, under the assumption that big memory spaces lead to good statistical multiplexing and hence efficient use of expensive long-haul links. In this paper, we summarize the works and present the experimental study result with big memory space size and give a qualitative analysis of the result. Our conclusion is that the, round-trip time (RTT is not increased by linear, but by quadric when the memory space size of the bottleneck is big enough. Our goal is to estimate the average queue length of the memory space size and develop a TCP model based on RTT and the average queue length.

  10. Comparison of High Speed Congestion Control Protocols

    Directory of Open Access Journals (Sweden)

    Jawhar Ben Abed

    2012-10-01

    Full Text Available Congestion control limits the quantity of information input at a rate less important than that of thetransmission one to ensure good performance as well as protect against overload and blocking of thenetwork. Researchers have done a great deal of work on improving congestion control protocols,especially on high speed networks.In this paper, we will be studying the congestion control alongside low and high speed congestion controlprotocols. We will be also simulating, evaluating, and comparing eight of high speed congestion controlprotocols : Bic TCP, Cubic TCP, Hamilton TCP, HighSpeed TCP, Illinois TCP, Scalable TCP,Compound TCP and YeAH TCP, with multiple flows.

  11. Evaluating of Urban Roads Congestion Based on Data Envelopment Analysis%基于DEA的城市道路交通拥堵评价

    Institute of Scientific and Technical Information of China (English)

    蒋金亮; 宋瑞; 李晋; 刘杰

    2011-01-01

    为了更好地分析和解决城市道路交通拥堵问题,以主干道为研究对象,将城市道路拥堵状态分为堵塞、拥堵、较拥堵、较畅通、畅通5个等级,从交叉口拥堵和路段拥堵2个方面筛选了衡量道路交通拥堵的评价指标,利用数据包络分析(DEA)建立了城市交通拥挤评价模型.以济南市北园大街主干道为例进行交通拥堵评价,得到该道路的拥堵状态以及产生拥堵的主要原因.结果表明数据包络分析方法在进行多指标评价综合评价中具有很强的抗干扰性,评价结果更客观.%For the purpose of analyzing and solving urban traffic congestion efficiently, urban arterial roads are taken as the object of study. In this study, congestion state of the urban traffic is classified at five levels: blocking, crawling, slow, less smooth, and smooth. Evaluation indexes which can be used to measure road traffic congestion are selected according to crossroad and lane congestion. Then, data envelopment analysis (DEA) is used to establish the evaluation model of road traffic congestion so as to provide an effective quantitative assessment method of urban road congestion.Taking Jinan North Park Avenue as an example to evaluate the road traffic congestion, this paper gets the information about the congestion status and the main reason. The result shows that the method of Data Envelopment Analysis has strong anti-interference during comprehensive evaluation of multiple indexes, making the result more objective.

  12. 基于奖励券机制的输电阻塞管理方法%Transmission Congestion Management Method Based on Coupon Incentive Mechanism

    Institute of Scientific and Technical Information of China (English)

    贾曦; 钟海旺; 夏清; 丁茂生; 宁波

    2013-01-01

      In view of the demand on improving the efficiency of asset utilization, the effective transmission congestion management in smart grid becomes much more important. Under the market mechanism integrated with locational marginal price (LMP) and the background of two-level market with two-settlement in day-ahead and real-time market, it is proposed that the transmission congestion surplus should be used to mitigate the congestion of transmission lines; and combining with the characteristics of the shadow price of congested lines and demand side price elasticity coefficient, it is proposed to lead in the LMP-redispatch cost factors (L-R Factors) as the foundation of measuring the impact of LMP variation on redispatch cost of power grid. On this basis, a coupon mechanism, in which the day-ahead congestion surplus is taken as the source of funds to motivate more demand response (DR) on shifting loads between different periods and then alleviate the congestion in real-time markets, is put forward, and an effective approach for congestion management is formed. Case study based on extended IEEE 30-bus system show that both the proposed mechanism and method are effective.%  鉴于对提高资产利用效率的要求,有效的输电阻塞管理在智能电网中的重要性日益凸显。在节点边际电价和日前与实时“两级市场、两步结算”的市场背景下,提出应将输电阻塞盈余用于缓解线路阻塞,并结合阻塞线路影子价格和用户需求价格弹性系数的特性,引入节点边际价格-再调度费用影响因子,作为衡量节点价格变化对系统再调度成本影响的依据。在此基础上,提出了以日前阻塞盈余作为资金来源,激励用户主动响应、缓解实时网络阻塞状况的奖励券机制,形成了阻塞管理新的有效方法。扩展的IEEE 30节点算例表明了所提机制与方法的有效性。

  13. Preventing Distribution Grid Congestion by Integrating Indirect Control in a Hierarchical Electric Vehicles Management System

    DEFF Research Database (Denmark)

    Hu, Junjie; Si, Chengyong; Lind, Morten

    2016-01-01

    In this paper, a hierarchical management system is proposed to integrate electric vehicles (EVs) into a distribution grid. Three types of actors are included in the system: Distribution system operators (DSOs), Fleet operators (FOs) and EV owners. In contrast to a typical hierarchical control...... system where the upper level controller directly controls the lower level subordinated nodes, this study aims to integrate two common indirect control methods:market-based control and price-based control into the hierarchical electric vehicles management system. Specifically, on the lower level...... of the hierarchy, the FOs coordinate the charging behaviors of their EV users using a price-based control method. A parametric utility model is used on the lower level to characterize price elasticity of electric vehicles and thus used by the FO to coordinate the individual EV charging. On the upper level...

  14. Computational Methods for Probabilistic Inference of Sector Congestion in Air Traffic Management

    OpenAIRE

    2013-01-01

    International audience; This article addresses the issue of computing the expected cost functions from a probabilistic model of the air traffic flow and capacity management. The Clenshaw-Curtis quadrature is compared to Monte-Carlo algorithms defined specifically for this problem. By tailoring the algorithms to this model, we reduce the computational burden in order to simulate real instances. The study shows that the Monte-Carlo algorithm is more sensible to the amount of uncertainty in the ...

  15. Use of intranasal corticosteroids in the management of congestion and sleep disturbance in pediatric patients with allergic rhinitis.

    Science.gov (United States)

    Lanier, Bob Q

    2008-06-01

    Allergic rhinitis affects a large number of children and exerts a considerable socioeconomic impact. It is underdiagnosed and inadequately treated, which predisposes children to potentially serious comorbidities. Allergic rhinitis symptoms may create nighttime breathing problems and sleep disturbances and have a negative effect on a child's ability to learn in the classroom. Although antihistamines have shown efficacy in relieving many symptoms, they have little effect on nasal congestion. This article summarizes the advantages of intranasal corticosteroids, including their effectiveness against congestion and excellent safety profile. Intranasal corticosteroids with minimal systemic bioavailability provide topical drug delivery that minimizes the potential for systemic side-effects.

  16. Evaluating the effects of urban congestion pricing : geographical accessibility versus social surplus

    NARCIS (Netherlands)

    Tillema, Taede; Verhoef, Erik; van Wee, Bert; van Amelsfort, Dirk; van Wee, G.P

    2011-01-01

    In urbanised areas around the world, road pricing policies are considered more and more frequently, the aim often being to alleviate (some of the) external traffic-related costs. To assess the effects of a proposed road pricing measure, several evaluation measures can be used, coming from different

  17. The London Congestion Charge

    National Research Council Canada - National Science Library

    Leape, Jonathan

    2006-01-01

    .... Traffic congestion has declined substantially, and the program is largely popular. This article describes the origins of the London congestion charge, how it overcame practical and theoretical difficulties, and what effects it has had...

  18. Assessment and management of human health risk from toxic metals and polycyclic aromatic hydrocarbons in urban stormwater arising from anthropogenic activities and traffic congestion.

    Science.gov (United States)

    Ma, Yukun; Liu, An; Egodawatta, Prasanna; McGree, James; Goonetilleke, Ashantha

    2017-02-01

    Toxic metals (TMs) and polycyclic aromatic hydrocarbons (PAHs) in urban stormwater pose risk to human health, thereby constraining its reuse potential. Based on the hypothesis that stormwater quality is primarily influenced by anthropogenic activities and traffic congestion, the primary focus of the research study was to analyse the impacts on human health risk from TMs and PAHs in urban stormwater and thereby develop a quantitative risk assessment model. The study found that anthropogenic activities and traffic congestion exert influence on the risk posed by TMs and PAHs in stormwater from commercial and residential areas. Motor vehicle related businesses (FVS) and traffic congestion (TC) were identified as two parameters which need to be included as independent variables to improve the model. Based on the study outcomes, approaches for mitigating the risk associated with TMs and PAHs in urban stormwater are discussed. Additionally, a roadmap is presented for the assessment and management of the risk arising from these pollutants. The study outcomes are expected to contribute to reducing the human health risk associated urban stormwater pollution and thereby enhance its reuse potential.

  19. Usefulness of the Sum of Pulmonary Capillary Wedge Pressure and Right Atrial Pressure as a Congestion Index that Prognosticates Heart Failure Survival (from the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness Trial).

    Science.gov (United States)

    Ma, Tony S; Paniagua, David; Denktas, Ali E; Jneid, Hani; Kar, Biswajit; Chan, Wenyaw; Bozkurt, Biykem

    2016-09-15

    In the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial, use of a pulmonary artery catheter did not significantly affect advanced heart failure outcomes. However, the success of achieving the targeted hemodynamic goals of pulmonary capillary wedge pressure (PCWP) of 15 mm Hg and right atrial pressure (RAP) of 8 mm Hg and the association of these goals with clinical outcomes were not addressed. Furthermore, goals with 2 independent variables, PCWP and RAP, left room for uncertainties. We assessed the ability of a single hemodynamic target to achieve a threshold sum of PCWP and RAP as a predictor of all-cause mortality, death-or-transplantation (DT), or death-or-rehospitalization (DR) at 6 months in the pulmonary artery catheter-guided treatment arm of ESCAPE (n = 206). Patients with a posttreatment PCWP + RAP of <30 mm Hg had characteristics similar to those of the population who achieved the ESCAPE hemodynamic goals. This group had 8.7% mortality, 13.0% DT, and 58.7% DR at 6 months. The contrasting cohort with PCWP + RAP of ≥30 mm Hg had 45.3% mortality, 54.7% DT, and 84.9% DR at 6 months, with greater relative risk (RR) of death (RR 5.76), DT (RR 4.92), and DR (RR 1.80) and higher prevalence of jugular venous pulsation, edema, hepatomegaly, and ascites at admission and discharge. In conclusion, PCWP + RAP of 30 mm Hg posttreatment, obtained early in the index hospitalization, may represent as a simple congestion index that has prognostic value for heart failure survival and readmission rates at 6 months and as a warning signal for more aggressive intervention, thus warranting further validation.

  20. Internet congestion control

    CERN Document Server

    Varma, Subir

    2015-01-01

    Internet Congestion Control provides a description of some of the most important topics in the area of congestion control in computer networks, with special emphasis on the analytical modeling of congestion control algorithms. The field of congestion control has seen many notable advances in recent years and the purpose of this book, which is targeted towards the advanced and intermediate reader, is to inform about the most important developments in this area. The book should enable the reader to gain a good understanding of the application of congestion control theory to a number of applic

  1. Pharmacological evaluation of selective α2c-adrenergic agonists in experimental animal models of nasal congestion.

    Science.gov (United States)

    Jia, Yanlin; Mingo, Garfield G; Hunter, John C; Lieber, Gissela B; Palamanda, Jairam R; Mei, Hong; Boyce, Christopher W; Koss, Michael C; Yu, Yongxin; Cicmil, Milenko; Hey, John A; McLeod, Robbie L

    2014-04-01

    Nasal congestion is one of the most troublesome symptoms of many upper airways diseases. We characterized the effect of selective α2c-adrenergic agonists in animal models of nasal congestion. In porcine mucosa tissue, compound A and compound B contracted nasal veins with only modest effects on arteries. In in vivo experiments, we examined the nasal decongestant dose-response characteristics, pharmacokinetic/pharmacodynamic relationship, duration of action, potential development of tolerance, and topical efficacy of α2c-adrenergic agonists. Acoustic rhinometry was used to determine nasal cavity dimensions following intranasal compound 48/80 (1%, 75 µl). In feline experiments, compound 48/80 decreased nasal cavity volume and minimum cross-sectional areas by 77% and 40%, respectively. Oral administration of compound A (0.1-3.0 mg/kg), compound B (0.3-5.0 mg/kg), and d-pseudoephedrine (0.3 and 1.0 mg/kg) produced dose-dependent decongestion. Unlike d-pseudoephedrine, compounds A and B did not alter systolic blood pressure. The plasma exposure of compound A to produce a robust decongestion (EC(80)) was 500 nM, which related well to the duration of action of approximately 4.0 hours. No tolerance to the decongestant effect of compound A (1.0 mg/kg p.o.) was observed. To study the topical efficacies of compounds A and B, the drugs were given topically 30 minutes after compound 48/80 (a therapeutic paradigm) where both agents reversed nasal congestion. Finally, nasal-decongestive activity was confirmed in the dog. We demonstrate that α2c-adrenergic agonists behave as nasal decongestants without cardiovascular actions in animal models of upper airway congestion.

  2. 城市交通拥堵缓解对车辆减排的效益研究%Evaluating the Benefits of Traffic Congestion Mitigation on Vehicles Emissions Reduction

    Institute of Scientific and Technical Information of China (English)

    单肖年; 叶建红; 陈小鸿

    2016-01-01

    城市交通拥堵缓解会释放潜在的交通需求,车辆减排的净效益与交通拥挤程度密切相关。本文利用弹性系数的概念,提出一种考虑潜在交通需求的城市交通拥堵缓解对车辆减排的效益研究方法。研究表明,车辆减排的净效益取决于潜在交通需求与单车减排效率间的平衡;对不同的污染物,车辆减排的净效益呈现不同的特征。此外,本文探究了私车牌照拍卖政策及快速机动化背景对拥堵缓解后车辆减排的效益影响。最后,定性分析了城市交通拥堵缓解策略对车辆减排的影响。研究成果对评估城市交通拥堵缓解的车辆减排净效益具有重要的理论及实际意义。%Traffic congestion mitigation can release the induced travel demand;the net benefits of vehicle emissions reduction are closely related with the traffic congestion level. A methodological framework to evaluate the benefits of traffic congestion mitigation on vehicles emissions reduction is established based on the concept of elasticity with considering the induced travel demand. Results show that the net benefits of vehicles emissions reduction depend on the balance of induced travel demand and one vehicle emissions reduction efficiency;and to the different pollutants, the net benefits of vehicles emissions reduction present different features. Furthermore, the vehicle license auction system in Shanghai is analyzed, as well as the rapid process of motorization in China. In the end, the influence of traffic management strategies to vehicles emissions reduction is analyzed. Findings can provide a methodological framework to evaluate the benefits of traffic congestion mitigation on vehicles emissions reduction with significant theoretical and practical purpose.

  3. “Playboy Bunny” Sign of Congestive Heart Failure

    Directory of Open Access Journals (Sweden)

    Fukunori Kinjo

    2011-05-01

    Full Text Available In emergency, ultrasound has been widely used as a non-invasive and effective examination to evaluate congestive heart failure. We highlight “Playboy Bunny” sign as a reliable marker and an important clue to the diagnosis of passive hepatic congestion, caused by congestive heart failure. [West J Emerg Med. 2011;12(4:433–434.

  4. Diagnostic strategies in nasal congestion

    Directory of Open Access Journals (Sweden)

    John Krouse

    2010-02-01

    Full Text Available John Krouse1, Valerie Lund2, Wytske Fokkens3, Eli O Meltzer41Temple University School of Medicine, Philadelphia, PA, USA; 2Ear Institute, University College London, UK; 3Department of Otorhinolaryngology, Amsterdam Medical Centre, Netherlands; 4Allergy and Asthma Medical Group and Research Center, San Diego, CA and Department of Pediatrics, University of California, San Diego, USAAbstract: Nasal congestion is a major symptom of upper respiratory tract disorders, and its characterization an important part of the diagnosis of these illnesses. Patient history and assessment of nasal symptoms are essential components of diagnosis, providing an initial evaluation that may be adequate to rule out serious conditions. However, current congestion medications are not always fully effective. Thus, if symptoms do not respond adequately to therapy, or symptoms suggestive of more serious conditions are present, specialized assessments may be needed. Various techniques are available for diagnosing patients, including those used chiefly by primary care clinicians and those requiring the expertise of otolaryngologists, allergists, and other specialists. Endoscopy remains a mainstay for evaluating nasal blockage and its causes, while modalities such as peak nasal inspiratory flow and acoustic rhinometry are evolving to provide easy-to-use, noninvasive procedures that are sensitive enough to measure small but clinically important abnormalities and therapeutic changes. Several imaging modalities are available to the specialist for severe or unusual cases, as are specialized diagnostic procedures that measure adjunctive features of congestion, such as impaired mucociliary function.Keywords: allergic rhinitis, congestion, diagnosis, obstruction, rhinosinusitis

  5. Model for cascading failures in congested Internet

    Institute of Scientific and Technical Information of China (English)

    Jian WANG; Yan-heng LIU; Jian-qi ZHU; Yu JIAO

    2008-01-01

    Cascading failures often occur in congested networks such as the Internet. A cascading failure can be described as a three-phase process: generation, diffusion, and dissipation of the congestion. In this account, we present a function that represents the extent of congestion on a given node. This approach is different from existing functions based on betweenness centrality. By introducing the concept of 'delay time', we designate an intergradation between permanent removal and nouremoval. We also construct an evaluation function of network efficiency, based on congestion, which measures the damage caused by cascading failures. Finally, we investigate the effects of network structure and size, delay time, processing ability and packet generation speed on congestion propagation. Also, we uncover the relationship between the cascade dynamics and some properties of the network such as structure and size.

  6. Congestion Relief of Contingent Power Network with Evolutionary Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Abhinandan De

    2012-03-01

    Full Text Available This paper presents a differential evolution optimization technique based methodology for congestion management cost optimization of contingent power networks. In Deregulated systems, line congestion apart from causing stability problems can increase the cost of electricity. Restraining line flow to a particular level of congestion is quite imperative from stability as well as economy point of view. Employing ‘Congestion Sensitivity Index’ proposed in this paper, the algorithm proposed can be adopted for selecting the congested lines in a power networks and then to search for a congestion constrained optimal generation schedule at the cost of a minimum ‘congestion management charge’ without any load curtailment and installation of FACTS devices. It has been depicted that the methodology on application can provide better operating conditions in terms of improvement of bus voltage and loss profile of the system. The efficiency of the proposed methodology has been tested on an IEEE 30 bus benchmark system and the results look promising.

  7. Analysis of Static Synchronous Series Compensators (SSSC, on Congestion Management and Voltage Profile in Power System by PSAT Toolbox

    Directory of Open Access Journals (Sweden)

    Hossein Nasir Aghdam

    2011-07-01

    Full Text Available The maintenance and availability of the power system can be considerd a major aspect of investigation. The encouragement to the planning of HV lines, the valuet of power that transfer per km on HV line and the amount of power transaction as seen from economic side is much responsible for concern towards congestion phenomena in power system. The idea for solving this problem is the use of FACTS devices especially the use of Synchronous Series Compensators (SSSC. In this paper the study of SSSC with its various modes of operation is investigated. Finally by help of modeling of a power system in MATLAB/PSAT toolbox, and by installing SSSC in transmission link, its use as power flow controller and voltage injection is seen. Conclusion is made on different results to see the benefit of SSSC in power system.

  8. Pathophysiology of nasal congestion

    Directory of Open Access Journals (Sweden)

    Robert M Naclerio

    2010-02-01

    Full Text Available Robert M Naclerio1, Claus Bachert2, James N Baraniuk31University of Chicago, Department of Surgery, Section of Otolaryngology – Head and Neck Surgery, Chicago, Illinois, USA; 2University of Ghent, Ghent, Belgium; 3Georgetown University, Washington, DC, USAAbstract: Nasal congestion is a common symptom in rhinitis (both allergic and nonallergic, rhinosinusitis and nasal polyposis. Congestion can also be caused by physical obstruction of nasal passages and/or modulation of sensory perception. Mucosal inflammation underlies many of the specific and interrelated factors that contribute to nasal congestion, as well as other symptoms of both allergic rhinitis and rhinosinusitis. A wide range of biologically active agents (eg, histamine, tumor necrosis factor-α, interleukins, cell adhesion molecules and cell types contribute to inflammation, which can manifest as venous engorgement, increased nasal secretions and tissue swelling/edema, ultimately leading to impaired airflow and the sensation of nasal congestion. Inflammation-induced changes in the properties of sensory afferents (eg, expression of peptides and receptors that innervate the nose can also contribute to altered sensory perception, which may result in a subjective feeling of congestion. Increased understanding of the mechanisms underlying inflammation can facilitate improved treatment selection and the development of new therapies for congestion.Keywords: allergic rhinitis, congestion, obstruction, pathophysiology, rhinosinusitis

  9. Managing congestion in distribution grids - Market design consideration. How heat pumps can deliver flexibility though well-designed markets and virtual power plant technology

    Energy Technology Data Exchange (ETDEWEB)

    Holmberg Rasmussen, L. [NEAS Energy, Aalborg (Denmark); Bang, C.; Togeby, M. [Ea Energy Analyses, Copenhagen (Denmark)

    2012-10-15

    of end-users to react to price fluctuations e.g. spot prices, thus enabling them to save on their electricity bill, and contribute to the overall system balance. The aim of this report is to discuss challenges with congestions in the distribution grids and how these can be solved through different tariffs and connection agreements, and how a market can be designed to manage congestion in local grids. A part of this is the investigation of the principal questions: Does the DSO have information about potential congestions, and what should the geographic scope of such a signal be? End-user demand can be controlled by a computer in each home which responds to a price signal that originates from the DSO, or it could be controlled by a centralised system, e.g. a virtual-power-plant (VPP) setup. The VPP set-up is in focus in this project, but the signal from the DSO should likely be useable in relation to both control solutions. How future signals from the DSO to the consumer would work in practice is open to discussion as there are a number of potential options, each which vary with respect to their geographic scope, timing, notice, and price level. Our initial findings indicate a number of issues that appear to be clear: 1) The signal indicating a potential congestion in distribution grids must originate from the DSO, and this signal will be directed to the retailer/aggregator/balance responsible, which will pass it on to end-users. 2) Ideally, the signal with grid tariffs should be sent to all end-users (not only heat pumps) in the congested area (i.e. possibly a small fraction of the DSO area). However, with more than 10,000 potential grids this may not be practical, and costs may not allow for this ideal solution. 3) Simple time-of-use tariffs can be an important first step in the direction of dynamic tariffs. Time-of-use tariffs can motivate behavioural change, i.e. computers and communication are not a requirement. It has not been analysed in detail how far in the

  10. FPGA Congestion-Driven Placement Refinement

    Energy Technology Data Exchange (ETDEWEB)

    Vicente de, J.

    2005-07-01

    The routing congestion usually limits the complete proficiency of the FPGA logic resources. A key question can be formulated regarding the benefits of estimating the congestion at placement stage. In the last years, it is gaining acceptance the idea of a detailed placement taking into account congestion. In this paper, we resort to the Thermodynamic Simulated Annealing (TSA) algorithm to perform a congestion-driven placement refinement on the top of the common Bounding-Box pre optimized solution. The adaptive properties of TSA allow the search to preserve the solution quality of the pre optimized solution while improving other fine-grain objectives. Regarding the cost function two approaches have been considered. In the first one Expected Occupation (EO), a detailed probabilistic model to account for channel congestion is evaluated. We show that in spite of the minute detail of EO, the inherent uncertainty of this probabilistic model impedes to relieve congestion beyond the sole application of the Bounding-Box cost function. In the second approach we resort to the fast Rectilinear Steiner Regions algorithm to perform not an estimation but a measurement of the global routing congestion. This second strategy allows us to successfully reduce the requested channel width for a set of benchmark circuits with respect to the widespread Versatile Place and Route (VPR) tool. (Author) 31 refs.

  11. Evaluation Of Lane Use Management Strategies

    OpenAIRE

    2014-01-01

    The limited funding available for roadway capacity expansion and the growing funding gap, in conjunction with the increasing congestion, creates a critical need for innovative lane use management options. Various cost-effective lane use management strategies have been implemented in the United States and worldwide to address these challenges. However, these strategies have their own costs, operational characteristics, and additional requirements for field deployment. Hence, there is a need fo...

  12. Managing congestion in distribution grids - Market design consideration. How heat pumps can deliver flexibility though well-designed markets and virtual power plant technology

    Energy Technology Data Exchange (ETDEWEB)

    Holmberg Rasmussen, L. [NEAS Energy, Aalborg (Denmark); Bang, C.; Togeby, M. [Ea Energy Analyses, Copenhagen (Denmark)

    2012-10-15

    of end-users to react to price fluctuations e.g. spot prices, thus enabling them to save on their electricity bill, and contribute to the overall system balance. The aim of this report is to discuss challenges with congestions in the distribution grids and how these can be solved through different tariffs and connection agreements, and how a market can be designed to manage congestion in local grids. A part of this is the investigation of the principal questions: Does the DSO have information about potential congestions, and what should the geographic scope of such a signal be? End-user demand can be controlled by a computer in each home which responds to a price signal that originates from the DSO, or it could be controlled by a centralised system, e.g. a virtual-power-plant (VPP) setup. The VPP set-up is in focus in this project, but the signal from the DSO should likely be useable in relation to both control solutions. How future signals from the DSO to the consumer would work in practice is open to discussion as there are a number of potential options, each which vary with respect to their geographic scope, timing, notice, and price level. Our initial findings indicate a number of issues that appear to be clear: 1) The signal indicating a potential congestion in distribution grids must originate from the DSO, and this signal will be directed to the retailer/aggregator/balance responsible, which will pass it on to end-users. 2) Ideally, the signal with grid tariffs should be sent to all end-users (not only heat pumps) in the congested area (i.e. possibly a small fraction of the DSO area). However, with more than 10,000 potential grids this may not be practical, and costs may not allow for this ideal solution. 3) Simple time-of-use tariffs can be an important first step in the direction of dynamic tariffs. Time-of-use tariffs can motivate behavioural change, i.e. computers and communication are not a requirement. It has not been analysed in detail how far in the

  13. Focus on renal congestion in heart failure.

    Science.gov (United States)

    Afsar, Baris; Ortiz, Alberto; Covic, Adrian; Solak, Yalcin; Goldsmith, David; Kanbay, Mehmet

    2016-02-01

    Hospitalizations due to heart failure are increasing steadily despite advances in medicine. Patients hospitalized for worsening heart failure have high mortality in hospital and within the months following discharge. Kidney dysfunction is associated with adverse outcomes in heart failure patients. Recent evidence suggests that both deterioration in kidney function and renal congestion are important prognostic factors in heart failure. Kidney congestion in heart failure results from low cardiac output (forward failure), tubuloglomerular feedback, increased intra-abdominal pressure or increased venous pressure. Regardless of the cause, renal congestion is associated with increased morbidity and mortality in heart failure. The impact on outcomes of renal decongestion strategies that do not compromise renal function should be explored in heart failure. These studies require novel diagnostic markers that identify early renal damage and renal congestion and allow monitoring of treatment responses in order to avoid severe worsening of renal function. In addition, there is an unmet need regarding evidence-based therapeutic management of renal congestion and worsening renal function. In the present review, we summarize the mechanisms, diagnosis, outcomes, prognostic markers and treatment options of renal congestion in heart failure.

  14. Desk Congest Desktop Congesting Software for Desktop Clutter Congestion

    Directory of Open Access Journals (Sweden)

    Solomon A. Adepoju

    2015-06-01

    Full Text Available Abstract The computer desktop environment is a working environment which can be likened unto a users desk in homes and offices. Often times the computer desktop get cluttered with files either as shortcuts used for quick links files stored temporarily to be accessed later or just being dumped there for no vivid reasons. However previous researches have shown that cluttered desktop affects users productivity and getting these files organized is a laborious task for most users. To be able to conveniently alleviate the effect clutters have on users performances and productivity there is need for third party software that will help get the desktop environment organized in a logical and efficient manner. It is to this end that desktop decongesting software is being designed and implemented to help curb clutter problems which existing tools have only partially addressed. The system is designed using Visual Basic .Net and it proves to be effective in tackling desktop congestion problem.

  15. Treatment of congestion in upper respiratory diseases

    Directory of Open Access Journals (Sweden)

    Eli O Meltzer

    2010-02-01

    Full Text Available Eli O Meltzer1, Fernan Caballero2, Leonard M Fromer3, John H Krouse4, Glenis Scadding51Allergy and Asthma Medical Group and Research Center, San Diego, CA and Department of Pediatrics, University of California, San Diego, USA; 2Allergy and Clinical Immunology Service, Centro Medico-Docente La Trinidad, Caracas, Venezuela; 3David Geffen School of Medicine, University of California, Los Angeles, USA; 4Wayne State University School of Medicine, Detroit, Michigan, USA; 5Department of Allergy and Rhinology, Royal National TNE Hospital, London, UKAbstract: Congestion, as a symptom of upper respiratory tract diseases including seasonal and perennial allergic rhinitis, acute and chronic rhinosinusitis, and nasal polyposis, is principally caused by mucosal inflammation. Though effective pharmacotherapy options exist, no agent is universally efficacious; therapeutic decisions must account for individual patient preferences. Oral H1-antihistamines, though effective for the common symptoms of allergic rhinitis, have modest decongestant action, as do leukotriene receptor antagonists. Intranasal antihistamines appear to improve congestion better than oral forms. Topical decongestants reduce congestion associated with allergic rhinitis, but local adverse effects make them unsuitable for long-term use. Oral decongestants show some efficacy against congestion in allergic rhinitis and the common cold, and can be combined with oral antihistamines. Intranasal corticosteroids have broad anti-inflammatory activities, are the most potent long-term pharmacologic treatment of congestion associated with allergic rhinitis, and show some congestion relief in rhinosinusitis and nasal polyposis. Immunotherapy and surgery may be used in some cases refractory to pharmacotherapy. Steps in congestion management include (1 diagnosis of the cause(s, (2 patient education and monitoring, (3 avoidance of environmental triggers where possible, (4 pharmacotherapy, and (5 immunotherapy

  16. 主动队列管理的PI/PID拥塞控制器的调节%Tuning PI/PID Congestion Controller for Active Queue Management

    Institute of Scientific and Technical Information of China (English)

    郑国庆; 张平健

    2007-01-01

    Active Queue Management strategies are important means for internet congestion control. However, it is hard to configure the controlling parameters to achieve good tradeoff among a set of performance objectives. Much work is devoted to find effective ways to parameter tuning. A simplified PI/PID controller for Active Queue Management was proposed and an empirical formula was utilized to tune the parameter of the controller. Simulation results demonstrate that the new controller shows some advantages over the traditional ones.%主动队列管理是一类重要的互联网拥塞控制策略.然而,要调节控制参数以达到性能目标是比较困难的,目前,许多研究工作致力于寻找简明有效的调节方法.提出了网络拥塞控制中主动队列管理的PI/PID控制器的一个简化模型,给出了控制器参数调节的经验公式.仿真结果表明,新的拥塞控制器简单易行,并具有系统响应时间短、网络流量吞吐率高等优点.

  17. Making the Traffic Operations Case for Congestion Pricing: Operational Impacts of Congestion Pricing

    Energy Technology Data Exchange (ETDEWEB)

    Chin, Shih-Miao [ORNL; Hu, Patricia S [ORNL; Davidson, Diane [ORNL

    2011-02-01

    delay, based on hours spent in traffic in a year, grew by 22% as the national average of hours spent in delay grew from 36 hours to 44 hours. Peak delay per traveler grew one-third in medium-size urban areas over the 10 year period. The traffic engineering community has developed an arsenal of integrated tools to mitigate the impacts of congestion on freeway throughput and performance, including pricing of capacity to manage demand for travel. Congestion pricing is a strategy which dynamically matches demand with available capacity. A congestion price is a user fee equal to the added cost imposed on other travelers as a result of the last traveler's entry into the highway network. The concept is based on the idea that motorists should pay for the additional congestion they create when entering a congested road. The concept calls for fees to vary according to the level of congestion with the price mechanism applied to make travelers more fully aware of the congestion externality they impose on other travelers and the system itself. The operational rationales for the institution of pricing strategies are to improve the efficiency of operations in a corridor and/or to better manage congestion. To this end, the objectives of this project were to: (1) Better understand and quantify the impacts of congestion pricing strategies on traffic operations through the study of actual projects, and (2) Better understand and quantify the impacts of congestion pricing strategies on traffic operations through the use of modeling and other analytical methods. Specifically, the project was to identify credible analytical procedures that FHWA can use to quantify the impacts of various congestion pricing strategies on traffic flow (throughput) and congestion.

  18. Altruism in Congestion Games

    CERN Document Server

    Hoefer, Martin

    2008-01-01

    This paper studies the effects of introducing altruistic agents into atomic congestion games. Altruistic behavior is modeled by a trade-off between selfish and social objectives. In particular, we assume agents optimize a linear combination of personal delay of a strategy and the resulting increase in social cost. Our model can be embedded in the framework of congestion games with player-specific latency functions. Stable states are the Nash equilibria of these games, and we examine their existence and the convergence of sequential best-response dynamics. Previous work shows that for symmetric singleton games with convex delays Nash equilibria are guaranteed to exist. For concave delay functions we observe that there are games without Nash equilibria and provide a polynomial time algorithm to decide existence for symmetric singleton games with arbitrary delay functions. Our algorithm can be extended to compute best and worst Nash equilibria if they exist. For more general congestion games existence becomes NP...

  19. Digoxin:A systematic review in atrial fibrillation,congestive heart failure and post myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    Sebastiano; Virgadamo; Richard; Charnigo; Yousef; Darrat; Gustavo; Morales; Claude; S; Elayi

    2015-01-01

    AIM: To review digoxin use in systolic congestive heart failure, atrial fibrillation, and after myocardial infarction. METHODS: A comprehensive Pub Med search was performed using the key words "digoxin and congestive heart failure", "digoxin and atrial fibrillation", "digoxin, atrial fibrillation and systolic congestive heart failure", and "digoxin and myocardial infarction". Only articles written in English were included in this study. We retained studies originating from randomized controlled trials, registries and included at least 500 patients. The studies included patients with atrial fibrillation or heart failure or myocardial infarction and had a significant proportion of patients(at least 5%) on digoxin. A table reviewing the different hazard ratios was developed based on the articles selected. Our primary endpoint was the overall mortality in the patients on digoxin vs those without digoxin, among patients with atrial fibrillation and also among patients with atrial fibrillation and systolic heart failure. We reviewed the most recent international guidelines to discuss current recommendations.RESULTS: A total of 18 studies were found that evaluated digoxin and overall mortality in different clinical settings including systolic congestive heart failure and normal sinus rhythm(n = 5), atrial fibrillation with and without systolic congestive heart failure(n = 9), and myocardial infarction(n = 4). Overall, patients with systolic congestive heart failure with normal sinus rhythm, digoxin appears to have a neutral effect on mortality especially if close digoxin level monitoring is employed. However, most of the observational studies evaluating digoxin use in atrial fibrillation without systolic congestive heart failure showed an increase in overall mortality when taking digoxin. In the studies evaluated in this systematic review, the data among patients with atrial fibrillation and systolic congestive heart failure, as well as post myocardial infarction were

  20. Congestion with incidents

    DEFF Research Database (Denmark)

    Fosgerau, Mogens

    2010-01-01

    This paper considers the impact of random delays during a repeatedly occurring demand peak in a congested facility, such as an airport or an urban road. Congestion is described in the form of a dynamic queue using the Vickrey bottleneck model and assuming Nash equilibrium in departure times. Every...... period an incident may occur at a random time, temporarily reducing the bottleneck capacity to zero. The paper gives some properties of Nash equilibrium and the social optimum as well as a pretty good welfare improving tolling scheme....

  1. Improved EPRCA Congestion Control Scheme for ATM Networks

    Directory of Open Access Journals (Sweden)

    Dr. M.Sreenivasulu

    2015-01-01

    Full Text Available Traffic management and congestion control are major issues in Asynchronous Transfer Mode(ATM networks. Congestion arises when traffic in the network is more than offered load. The primary function of congestion control is to ensure good throughput and low delay performance while maintaining a fair allocation of network resources to users. In this paper, Enhanced Proportional Rate based Congestion Avoidance (EPRCA scheme proposed by ATM forum has been considered. But this scheme has limitation of higher cell drop problem for the bursty traffic. Improvements to EPRCA scheme have been proposed to reduce cell drop problem and results of improved EPRCA schemes were analyzed with basic EPRCA scheme.

  2. Green supply chain management using the queuing theory to handle congestion and reduce energy consumption and emissions from supply chain transportation fleet

    Directory of Open Access Journals (Sweden)

    Arvin Aziziankohan

    2017-05-01

    Full Text Available Purpose: Nowadays, governments and people pay more attention to use green products due to environmental pollution, irreplaceable energy and shortage of resources. Green products are resulted from the application of green supply chain management strategies to the organizations' performance strategies, so that we can reduce environmental pollutants and wastes and take a step towards saving energy with limited resources. Methodology:  In this paper, the effect of reducing energy consumption in green supply chain is examined by using queuing theory and transportation models. Data was generated and solved by a commercial optimization epackage. Findings:  The findings indicate that suitable assignment of existing transportation fleet with specified capacity, and using queueing theory in a closed-loop network to reduce the queue length and handle congestion, can cause a reduction in energy consumption by optimizing transportation and waiting times in a green supply chain. Originality/value: Adopting investment strategy in improving the environmental performance of the supply chain, will yield in many advantages and benefits. This article investigates the effect of queuing theory on reducing waiting time, optimizing energy consumption in green supply chain, and consequently decreasing pollution.

  3. 浅谈城市道路交通拥堵管理系统%On Urban Road Traffic Congestion Management System

    Institute of Scientific and Technical Information of China (English)

    邓林

    2014-01-01

    随着我国汽车数量的急剧增加,在各种因素的影响下,大小交通事故频繁出现,严重影响了城市道路的行车效率。基于以上,对城市道路交通拥堵管理系统进行了分析与研究,介绍了该管理系统的平台,子模块的主要功能,并对关键技术进行着重的阐述。%With the rapid increase of automobile's quantity in China, under the influence of various factors, traffic accidents occur frequently, which has serious impact on the urban road traffic efficiency. Based on the above factors, urban road traffic congestion management system is analyzed and studied. The development platform and main function modules are introduced, and the key technologies are emphatically described.

  4. Comparative Study on New AQM Mechanisms for Congestion Control

    Directory of Open Access Journals (Sweden)

    Ramakrishna B B

    2013-09-01

    Full Text Available As usage of network goes increasing day by day, managing network traffic becomes a very difficult task. It is important to avoid high packet loss rates in the Internet. Congestion is the one of the major issue in the present networks. Congestion Control is one of the solutions adopted to solve the congestion issue and to control it. Numbers of queue management algorithms are proposed for congestion control and to reduce high packet loss rates. Active Queue Management (AQM is one such mechanism which provides better control over congestion. In this paper a study is made on recent load based AQM techniques that are proposed and its merits and shortfall is presented.

  5. The London Congestion Charge

    National Research Council Canada - National Science Library

    Leape, Jonathan

    2006-01-01

    .... In early 2003, London imposed a congestion charge—a daily charge for driving or parking a vehicle on public roads within central London between the hours of 7:00 a.m. and 6:30 p.m. on workdays...

  6. Study on Evaluation of Urban Traffic Congestion Based on Fuzzy Comprehensive Evaluation%基于模糊综合评价法的城市道路拥堵评价方法研究

    Institute of Scientific and Technical Information of China (English)

    段亚丽; 高国天

    2013-01-01

    针对城市道路拥堵问题,以实现对城市道路拥堵状况评估为目标,在智能运行平台海量数据的基础上,综合考虑影响城市道路交通的各个因素,从评价指标的选取、评价标准的确定和评价体系的组成等角度叙述建立城市道路拥堵评价体系的具体方法,同时利用模糊综合评价法对道路拥堵体系进行求解,并通过实例阐述该评价方法的具体应用过程,证明该方法的正确性。%In this paper, in view of the problem of urban traffic congestion, we considered comprehensively the various factors influencing urban road traffic, then from the aspects of the selection of the evaluation indexes, the determination of the evaluation standard and the composition of the evaluation system, etc., introduced the specific method for the establishment of the urban traffic congestion evaluation system, used the fuzzy comprehensive evaluation method to solve the traffic congestion system, and at the end used a practical case to demonstrate the application of the evaluation method and its effectiveness.

  7. Relief and Recurrence of Congestion During and After Hospitalization for Acute Heart Failure: Insights From Diuretic Optimization Strategy Evaluation in Acute Decompensated Heart Failure (DOSE-AHF) and Cardiorenal Rescue Study in Acute Decompensated Heart Failure (CARESS-HF).

    Science.gov (United States)

    Lala, Anuradha; McNulty, Steven E; Mentz, Robert J; Dunlay, Shannon M; Vader, Justin M; AbouEzzeddine, Omar F; DeVore, Adam D; Khazanie, Prateeti; Redfield, Margaret M; Goldsmith, Steven R; Bart, Bradley A; Anstrom, Kevin J; Felker, G Michael; Hernandez, Adrian F; Stevenson, Lynne W

    2015-07-01

    Congestion is the most frequent cause for hospitalization in acute decompensated heart failure. Although decongestion is a major goal of acute therapy, it is unclear how the clinical components of congestion (eg, peripheral edema, orthopnea) contribute to outcomes after discharge or how well decongestion is maintained. A post hoc analysis was performed of 496 patients enrolled in the Diuretic Optimization Strategy Evaluation in Acute Decompensated Heart Failure (DOSE-AHF) and Cardiorenal Rescue Study in Acute Decompensated Heart Failure (CARRESS-HF) trials during hospitalization with acute decompensated heart failure and clinical congestion. A simple orthodema congestion score was generated based on symptoms of orthopnea (≥2 pillows=2 points, <2 pillows=0 points) and peripheral edema (trace=0 points, moderate=1 point, severe=2 points) at baseline, discharge, and 60-day follow-up. Orthodema scores were classified as absent (score of 0), low-grade (score of 1-2), and high-grade (score of 3-4), and the association with death, rehospitalization, or unscheduled medical visits through 60 days was assessed. At baseline, 65% of patients had high-grade orthodema and 35% had low-grade orthodema. At discharge, 52% patients were free from orthodema at discharge (score=0) and these patients had lower 60-day rates of death, rehospitalization, or unscheduled visits (50%) compared with those with low-grade or high-grade orthodema (52% and 68%, respectively; P=0.038). Of the patients without orthodema at discharge, 27% relapsed to low-grade orthodema and 38% to high-grade orthodema at 60-day follow-up. Increased severity of congestion by a simple orthodema assessment is associated with increased morbidity and mortality. Despite intent to relieve congestion, current therapy often fails to relieve orthodema during hospitalization or to prevent recurrence after discharge. URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00608491, NCT00577135. © 2015 American Heart

  8. Congestive Heart Failure and Central Sleep Apnea.

    Science.gov (United States)

    Sands, Scott A; Owens, Robert L

    2016-03-01

    Congestive heart failure (CHF) is among the most common causes of admission to hospitals in the United States, especially in those over age 65. Few data exist regarding the prevalence CHF of Cheyne-Stokes respiration (CSR) owing to congestive heart failure in the intensive care unit (ICU). Nevertheless, CSR is expected to be highly prevalent among those with CHF. Treatment should focus on the underlying mechanisms by which CHF increases loop gain and promotes unstable breathing. Few data are available to determine prevalence of CSR in the ICU, or how CSR might affect clinical management and weaning from mechanical ventilation.

  9. Project Management Personnel Competencies Evaluation

    Directory of Open Access Journals (Sweden)

    Paul POCATILU

    2006-01-01

    Full Text Available An important factor for the success management of IT projects is the human resource. People involved in the project management process have to be evaluated. In order to do that, same criteria has to be specified. This paper describes some aspects regarding the personnel evaluation.

  10. Electricity transmission congestion costs: A review of recent reports

    Energy Technology Data Exchange (ETDEWEB)

    Lesieutre, Bernard C.; Eto, Joseph H.

    2003-10-01

    Recently, independent system operators (ISOs) and others have published reports on the costs of transmission congestion. The magnitude of congestion costs cited in these reports has contributed to the national discussion on the current state of U.S. electricity transmission system and whether it provides an adequate platform for competition in wholesale electricity markets. This report reviews reports of congestion costs and begins to assess their implications for the current national discussion on the importance of the U.S. electricity transmission system for enabling competitive wholesale electricity markets. As a guiding principle, we posit that a more robust electricity system could reduce congestion costs; and thereby, (1) facilitate more vibrant and fair competition in wholesale electricity markets, and (2) enable consumers to seek out the lowest prices for electricity. Yet, examining the details suggests that, sometimes, there will be trade-offs between these goals. Therefore, it is essential to understand who pays, how much, and how do they benefit in evaluating options (both transmission and non-transmission alternatives) to address transmission congestion. To describe the differences among published estimates of congestion costs, we develop and motivate three ways by which transmission congestion costs are calculated in restructured markets. The assessment demonstrates that published transmission congestion costs are not directly comparable because they have been developed to serve different purposes. More importantly, critical information needed to make them more comparable, for example in order to evaluate the impacts of options to relieve congestion, is sometimes not available.

  11. Role of Diuretics and Ultrafiltration in Congestive Heart Failure

    Directory of Open Access Journals (Sweden)

    Jo Ann Lindenfeld

    2013-07-01

    Full Text Available Volume overload in heart failure (HF results from neurohumoral activation causing renal sodium and water retention secondary to arterial underfilling. Volume overload not only causes signs and symptoms of congestion, but can impact myocardial remodeling and HF progression. Thus, treating congestion is a cornerstone of HF management. Loop diuretics are the most commonly used drugs in this setting. However, up to 30% of the patients with decompensated HF present with loop-diuretic resistance. A universally accepted definition of loop diuretic resistance, however, is lacking. Several approaches to treat diuretic-resistant HF are available, including addition of distal acting thiazide diuretics, natriuretic doses of mineralocorticoid receptor antagonists (MRAs, or vasoactive drugs. Slow continuous veno-venous ultrafiltration is another option. Ultrafiltration, if it is started early in the course of HF decompensation, may result in prominent decongestion and a reduction in re-hospitalization. On the other hand, ultrafiltration in HF patients with worsening renal function and volume overload after aggressive treatment with loop diuretics, failed to show benefit compared to a stepwise pharmacological approach, including diuretics and vasoactive drugs. Early detection of congested HF patients for ultrafiltration treatment might improve decongestion and reduce readmission. However, the best patient characteristics and best timing of ultrafiltration requires further evaluation in randomized controlled studies.

  12. Role of Diuretics and Ultrafiltration in Congestive Heart Failure

    Science.gov (United States)

    Shchekochikhin, Dmitry; Al Ammary, Fawaz; Lindenfeld, JoAnn; Schrier, Robert

    2013-01-01

    Volume overload in heart failure (HF) results from neurohumoral activation causing renal sodium and water retention secondary to arterial underfilling. Volume overload not only causes signs and symptoms of congestion, but can impact myocardial remodeling and HF progression. Thus, treating congestion is a cornerstone of HF management. Loop diuretics are the most commonly used drugs in this setting. However, up to 30% of the patients with decompensated HF present with loop-diuretic resistance. A universally accepted definition of loop diuretic resistance, however, is lacking. Several approaches to treat diuretic-resistant HF are available, including addition of distal acting thiazide diuretics, natriuretic doses of mineralocorticoid receptor antagonists (MRAs), or vasoactive drugs. Slow continuous veno-venous ultrafiltration is another option. Ultrafiltration, if it is started early in the course of HF decompensation, may result in prominent decongestion and a reduction in re-hospitalization. On the other hand, ultrafiltration in HF patients with worsening renal function and volume overload after aggressive treatment with loop diuretics, failed to show benefit compared to a stepwise pharmacological approach, including diuretics and vasoactive drugs. Early detection of congested HF patients for ultrafiltration treatment might improve decongestion and reduce readmission. However, the best patient characteristics and best timing of ultrafiltration requires further evaluation in randomized controlled studies. PMID:24276318

  13. New Strategy for Congestion Control based on Dynamic Adjustment of Congestion Window

    Directory of Open Access Journals (Sweden)

    Gamal Attiya

    2012-03-01

    Full Text Available This paper presents a new mechanism for the end-to-end congestion control, called EnewReno. The proposed mechanism is based on the enhancement of both the congestion avoidance and the fast recovery algorithms of the TCP NewReno so as to improve its performance. The basic idea of the proposed mechanism is to adjust the congestion window of the TCP sender dynamically based on the level of congestion in the network so as to allow transferring more packets to the destination. The performance of the proposed mechanism is evaluated and compared with the most recent mechanisms by simulation studies using the well known Network Simulator NS-2 and the realistic topology generator GT-ITM.

  14. 显示拥塞指示标记的主动队列管理研究%Active queue management with explicit congestion notification marks

    Institute of Scientific and Technical Information of China (English)

    闫巧; 胡晓娟

    2012-01-01

    主动队列管理对于解决网路拥塞具有重要意义.针对PID主动队列管理算法在调节队列长度时有较大的丢包率这一缺点,提出一种显示拥塞指示标记即ECN标记的PID主动队列管理算法.该算法用显示拥塞指示标记取代丢包机制,用于通知源端网络即将发生拥塞,采用PID控制器实现反馈控制,保证系统的稳定性.仿真结果表明,显示拥塞指示标记的主动队列管理算法适用于多变的网络环境,比PID算法具有低丢包率、低延时和高吞吐量的特点.%Active Queue Management(AQM) is very significant for network congestion control. This paper presents a new PID controller for AQM with ECN marks to overcome the shortcomings of PID AQM--high loss rate. In this algorithm, the mechanism ofdropping packet is replaced with ECN marks. It uses the PID controller as feed-backward compensation to ensure the stability of the system. The results of simulation show that the PID controller for AQM with ECN marks can adapt to the changing network environment and has lower loss rate, lower delay and higher throughput than the conventional PID AQM algorithm.

  15. New Public Management and Evaluation

    NARCIS (Netherlands)

    F.B.L. van der Meer (Frans-Bauke)

    2007-01-01

    textabstractIn this chapter I will discuss what evaluation does and can contribute to insight in the dynamics and effects of (new) public management reforms. To do so, I pose three key ques-tions: 1. How is evaluation actually applied in relation to NPM-reforms? 2. How are evaluation results used an

  16. Public Management and Evaluation

    NARCIS (Netherlands)

    F.B.L. van der Meer (Frans-Bauke)

    2007-01-01

    textabstractIn public management we can observe a continuous search for its own improvement. New arrangements and procedures, often derived from NPM ideas, but also from other PA insights, are put in place with the expectations that public administration as well as its related agencies and networks

  17. [Anemia in congestive heart failure].

    Science.gov (United States)

    Abassade, P; Rabenirina, F; Garcon, P; Antakly, Y; Cador, R

    2009-11-01

    Anemia is a common disorder in congestive heart failure and an independant prognostic factor. The aims of this study are to evaluate the prevalence of anemia among a population of in-hospital congestive heart failure patients, to compare anemic patients (A) with non anemic patients (NA) and to study their cares. One hundred and thirty-two patients, 70 men (53%), et 62 women (47%) are enrolled. Mean age is 76.4+/-13.5 years. The prevalence of anemia (WHO criteria) is 49%. Patients A are older than NA: 79.1+/-13.8 years versus 73.8+/-12.9 years (p=0.025), renal function is more altered in A than in NA, creatinine clearance is 56.5 ml/min (A) versus 76.2 ml/min (NA) (p=0.003). Ejection fraction (EF) is lower in A than in NA: 35.1+/-15.3% versus 50.9+/-15.9%, (pAnemia is less frequent in preserved EF (28%) than in low EF (63%) (pAnemia is frequent in our population, and is associated with others prognostic factors and comorbidity.

  18. Power Preservation Friendly Congestion Control

    Directory of Open Access Journals (Sweden)

    Ittipong Khemapech

    2014-03-01

    Full Text Available Wireless sensor networks (WSNs are an important area with a major technological impact. Power preservation is one of the important issues in communication protocol development for WSNs. This article presents a review of Event-to-Sink Reliable Transport (ESRT which is specifically developed for an event-based WSNs application. Five characteristic regions and corresponding algorithms have been proposed in ESRT. At the end of each cycle, the reliability is observed and the data reporting rate is adjusted accordingly. Two main contributions of this study include an evaluation of the algorithms proposed by ESRT on their capabilities of power preservation and convergence to the optimal state where a sink receives a desired number of received packets and there is no congestion. According to the results, all of the algorithms demonstrate profound reporting rate adjustments. Moreover, both transmitting and receiving powers can be significantly preserved in the case when the sources generated more packets than required and the network is congested. Therefore, the proposed algorithms unlikely require any enhancements. Moreover, ESRT is analysed how well it can fit in some of the existing WSNs applications. The application category which may deploy ESRT is the event detection and tracking where complete reliability is not required.

  19. Test & Evaluation Management Guide

    Science.gov (United States)

    2012-12-01

    conducted, using munitions likely to be encountered in combat, on a complete system loaded or equipped with all the dangerous materials that normally would...systems, work scope, contracting approaches, efficiency, requirements creep , and risk management. 15.11.3 Agile Development and Testing Testing within an...White Sands Missile Range, New Mexico, aerodynamic simulations of the proposed test were run on a computer during actual firings so that real-time

  20. Congestion Control in 4G Wireless Networks Using Coalition Game

    Directory of Open Access Journals (Sweden)

    S. V. Saboji

    2012-06-01

    Full Text Available In 4G-domain multi home mobile host (MH will have access to different wireless networks. In this 4G wireless networks real time applications are initiated to support services like VOIP, videoconference. These applications use RTP over UDP. These protocols are unresponsive to congestion events. Our proposed congestion management scheme minimizes congestion level in 4G domains using coalition game. Its main objective is to decide target networks for handoff with minimum congestion level. Our mechanism is based on the coalition game formation. It aims at maximizing the utilization of the resources available and meeting QoS requirement of users as much as possible. This will reduce congestion level with vertical handoff initiation.

  1. Utilization-Based Congestion Control

    OpenAIRE

    Satoshi Utsumi; Salahuddin Muhammad Salim Zabir

    2012-01-01

    Traditional connection oriented protocols like TCP NewReno perform poorly over wireless links. Theproblem lies in their design assumptions based on loss based congestion control. Various modificationsto loss based congestion control schemes have so far been proposed to overcome the issue. In addition,the comparatively newer family of delay based congestion control mechanisms like Caia-Hamilton Delay(CHD), offer effective solutions for wireless link loss. All these approaches aim at improving ...

  2. 一种适于Internet拥塞控制的自校正队列管理算法%A Self-Tuning Queue Management Algorithm for Internet Congestion Control

    Institute of Scientific and Technical Information of China (English)

    张敬辕; 谢剑英; 刘立祥

    2002-01-01

    As an effective method for congestion control, Active Queue Management plays an important role in im-proving the Internet QoS. In this paper,we first analyze the properties of RED,then design an effective queue manage-ment algorithm based on gradient descent approach. With the application of this algorithm,routers in IP network ad-just its packet drop probability according to the queue length in the buffer. The main advantage of this algorithm isthat the queue length can keep stable at a low level in a varity of network environments. Simulations show that thisself-tuning queue management algorithm is efficient,stable and outperforms RED queue management algorithms sig-nificantly.

  3. Slot allocation on congested motorways: An alternative to congestion pricing

    NARCIS (Netherlands)

    Koolstra, K.

    1999-01-01

    With respect to the prevailing congestion problems in the more urbanised regions of the European Union, transportation planners and policymakers are facing a dilemma. Supply-side measures, i.e. increasing the capacities, might shorten the congestion duration, especially if bottlenecks can be removed

  4. Slot allocation on congested motorways: An alternative to congestion pricing

    NARCIS (Netherlands)

    Koolstra, K.

    1999-01-01

    With respect to the prevailing congestion problems in the more urbanised regions of the European Union, transportation planners and policymakers are facing a dilemma. Supply-side measures, i.e. increasing the capacities, might shorten the congestion duration, especially if bottlenecks can be removed

  5. Car-following under non-congested and congested conditions

    NARCIS (Netherlands)

    Dijker, T.; Bovy, P.H.L.; Vermijs, R.G.M.M.

    1997-01-01

    In traffic flow analysis several regimes are distinguished, such as congested and non-congested flow conditions. Indications exist that driving behavior differs by regime, and that it may change discontinuously between regimes. In contrast, most traffic flow models used today basically assume the sa

  6. Mathematical principles of road congestion pricing

    Directory of Open Access Journals (Sweden)

    WJ Pienaar

    2009-06-01

    Full Text Available This paper briefly considers the objectives of road congestion pricing and identifies prerequisites to the successful application of such a pricing scheme. The paper is divided into two sections. In the first section, a mathematical analysis of the constituents of an optimal road congestion price is offered. The eliminated inefficiency loss achieved by the introduction of a congestion levy is usually evaluated by means of an integral involving marginal trip cost, travel demand and average trip cost in two-dimensional (travel time, traffic flow-space. In this section we show that this loss may, in fact, be evaluated more easily for a general marginal trip cost function and a linear demand function as the difference between the areas of a rectangle (representing the part of road agency revenue that lies below the original trip cost and a triangle (representing the loss of consumer surplus of the reduced traffic in (travel time, traffic flow-space, eliminating the need to use integration. The next section deals with the application of the illustrated mathematical principles and proofs to a hypothetical case study relating to road congestion pricing in Cape Town.

  7. Endovascular Treatment of Pelvic Congestion Syndrome: Visual Analog Scale (VAS) Long-Term Follow-up Clinical Evaluation in 202 Patients

    Energy Technology Data Exchange (ETDEWEB)

    Laborda, Alicia, E-mail: alaborda@unizar.es; Medrano, Joaquin, E-mail: oauieao@gmail.com [University of Zaragoza, Group of Research in Minimally Invasive Techniques Research (GITMI) (Spain); Blas, Ignacio de, E-mail: deblas@unizar.es [University of Zaragoza, Edificio Hospital Veterinario, Department of Animal Pathology (Unit of Infectious Diseases and Epidemiology) (Spain); Urtiaga, Ignacio, E-mail: info@doctorurtiaga.com [Hospital Clinico Universitario ' Lozano Blesa' , Department of Vascular Surgery (Spain); Carnevale, Francisco Cesar, E-mail: fcarnevale@uol.com.br [University of Sao Paulo, Medical School, Interventional Radiology (Brazil); Gregorio, Miguel A. de, E-mail: mgregori@unizar.es [University of Zaragoza, Group of Research in Minimally Invasive Techniques Research (GITMI) (Spain)

    2013-08-01

    PurposeThis study was designed to evaluate the clinical outcome and patients' satisfaction after a 5 year follow-up period for pelvic congestion syndrome (PCS) coil embolization in patients who suffered from chronic pelvic pain that initially consulted for lower limb venous insufficiency.MethodsA total of 202 patients suffering from chronic pelvic pain were recruited prospectively in a single center (mean age 43.5 years; range 27-57) where they were being treated for lower limb varices. Inclusion criteria were: lower limb varices and chronic pelvic pain (>6 months), >6 mm pelvic venous caliber in ultrasonography, and venous reflux or presence of communicating veins. Both ovarian and hypogastric veins were targeted for embolization. Pain level was assessed before and after embolotherapy and during follow-up using a visual analog scale (VAS). Technical and clinical success and recurrence of leg varices were studied. Patients completed a quality questionnaire. Clinical follow-up was performed at 1, 3, and 6 months and every year for 5 years.ResultsTechnical success was 100 %. Clinical success was achieved in 168 patients (93.85 %), with complete disappearance of symptoms in 60 patients (33.52 %). Pain score (VAS) was 7.34 {+-} 0.7 preprocedural versus 0.78 {+-} 1.2 at the end of follow-up (P < 0.0001). Complications were: groin hematoma (n = 6), coil migration (n = 4), and reaction to contrast media (n = 1). Twenty-three cases presented abdominal pain after procedure. In 24 patients (12.5 %), there was recurrence of their leg varices within the follow-up. The mean degree of patients' satisfaction was 7.4/9.ConclusionsCoil embolization of PCS is an effective and safe procedure, with high clinical success rate and degree of satisfaction.

  8. Prognostic value of plasma catecholamines, plasma renin activity, and plasma atrial natriuretic peptide at rest and during exercise in congestive heart failure: comparison with clinical evaluation, ejection fraction, and exercise capacity

    DEFF Research Database (Denmark)

    Madsen, B K; Keller, N; Christiansen, E

    1995-01-01

    carried significant, independent prognostic information in a multivariate analysis: left ventricular ejection fraction (P = .03), plasma noradrenaline at rest (P = .009), New York Heart Association class III + IV (P = .005), increase in heart rate during exercise ... creatinine > 121 mumol/L (P = .004), and serum urea > 7.6 mmol/L (P = .007). Patients with congestive heart failure have a poor survival despite intensive medical treatment. Plasma catecholamines and plasma atrial natriuretic peptide are elevated at rest and rises further during exercise; the increase......Survival in congestive heart failure is related to plasma catecholamines and atrial natriuretic peptide at rest, but the prognostic importance of changes during exercise is unknown. The aim of this study was to evaluate the prognostic value of catecholamines and atrial natriuretic peptide at rest...

  9. Cardiac CT Angiography in Congestive Heart Failure.

    Science.gov (United States)

    Levine, Avi; Hecht, Harvey S

    2015-06-01

    Cardiac CT angiography has become an important tool for the diagnosis and treatment of congestive heart failure. Differentiation of ischemic from nonischemic cardiomyopathy; evaluation of myocardial perfusion; characterization of hypertrophic cardiomyopathy, left ventricular noncompaction, and arrhythmogenic right ventricular dysplasia; and delineation of congenital heart defects and valvular abnormalities are the primary diagnostic applications. Therapeutic use includes visualization of the coronary venous anatomy for optimal implementation of cardiac resynchronization therapy and evaluation of left ventricular assist devices and transplant vasculopathy.

  10. Development and Evaluation of a Control System for Regional Traffic Management

    Directory of Open Access Journals (Sweden)

    John L. McLin

    2011-01-01

    Full Text Available Traffic congestion is a worsening problem in metropolitan areas which will require integrated regional traffic control systems to improve traffic conditions. This paper presents a regional traffic control system which can detect incident conditions and provide integrated traffic management during nonrecurrent congestion events. The system combines advanced artificial intelligence techniques with a traffic performance model based on HCM equations. Preliminary evaluation of the control system using traffic microsimulation demonstrates that it has the potential to improve system conditions during traffic incidents. In addition, several enhancements were identified which will make the system more robust in a real traffic control setting. An assessment of the control system elements indicates that there are no substantial technical barriers in implementing this system in a large traffic network.

  11. Outcomes and lessons learned from evaluating TRICARE's disease management programs.

    Science.gov (United States)

    Dall, Timothy M; Askarinam Wagner, Rachel C; Zhang, Yiduo; Yang, Wenya; Arday, David R; Gantt, Cynthia J

    2010-06-01

    To share outcomes and lessons learned from an evaluation of disease management (DM) programs for asthma, congestive heart failure (CHF), and diabetes for TRICARE patients. Multiyear evaluation of participants in voluntary, opt-out DM programs. Patient-centered programs, administered by 3 regional contractors, provide phone-based consultations with a care manager, educational materials, and newsletters. The study sample consisted of 23,793 asthma, 4092 CHF, and 29,604 diabetes patients with at least 6 months' tenure in the program. Medical claims were analyzed to quantify program effect on healthcare utilization, medical costs, and clinical outcomes. Multivariate regression analysis with an historical control group was used to predict patient outcomes in the absence of DM. The difference between actual and predicted DM patient outcomes was attributed to the program. A patient survey collected data on program satisfaction and perceived usefulness of program information and services. Modest improvements in patient outcomes included reduced inpatient days and medical costs, and (with few exceptions) increased percentages of patients receiving appropriate medications and tests. Annual per patient reductions in medical costs were $453, $371, and $783 for asthma, CHF, and diabetes program participants, respectively. The estimated return on investment was $1.26 per $1.00 spent on DM services. Findings suggest that the DM programs more than pay for themselves, in addition to improving patient health and quality of life. Lessons learned in program design, implementation, effectiveness, and evaluation may benefit employers contemplating DM, DM providers, and evaluators of DM programs.

  12. HSUPA Transport Network Congestion Control

    Directory of Open Access Journals (Sweden)

    Szilveszter Nádas

    2009-01-01

    Full Text Available The introduction of High Speed Uplink Packet Access (HSUPA greatly improves achievable uplink bitrate but it presents new challenges to be solved in the WCDMA radio access network. In the transport network, bandwidth reservation for HSUPA is not efficient and TCP cannot efficiently resolve congestion because of lower layer retransmissions. This paper proposes an HSUPA transport network flow control algorithm that handles congestion situations efficiently and supports Quality of Service differentiation. In the Radio Network Controller (RNC, transport network congestion is detected. Relying on the standardized control frame, the RNC notifies the Node B about transport network congestion. In case of transport network congestion, the Node B part of the HSUPA flow control instructs the air interface scheduler to reduce the bitrate of the flow to eliminate congestion. The performance analysis concentrates on transport network limited scenarios. It is shown that TCP cannot provide efficient congestion control. The proposed algorithm can achieve high end-user perceived throughput, while maintaining low delay, loss, and good fairness in the transport network.

  13. Evaluation on Traffic Congestion Mitigation in Beijing with Variable Message Signs%可变信息屏对北京市交通拥堵缓解的评价研究

    Institute of Scientific and Technical Information of China (English)

    周洋帆; 贾顺平; 关伟; 刘爽

    2014-01-01

    The variable message signs (VMS) provide an effective method to mitigate urban traffic congestion and balance traffic demand through publishing guidance messages. For evaluating the mitigating effect of VMS on congestion, a general-purpose model utilizing the data mining method is developed . The data includes published messages and a large amount of historical traffic flow collected from VMS publishing system and detectors which reflects the most realistic traffic conditions in Beijing road traffic network. Specially, road traffic statuses under two types of messages, guidance message and notice message, are compared to recognize which one is more effective. In the case study, spatial and temporal analyses are introduced separately to evaluate the mitigation of congestion under various traffic conditions. The results indicate that guidance messages on VMS make more significant contributions to improve the level of service of congested roads. Particularly, guidance messages always appeared more effective than notice messages under severe congestion.%可变信息屏(VMS)为缓解大城市交通拥堵提供了一种有效途径,它通过发布诱导信息来均衡路网上的交通需求。为了评价VMS对缓解交通拥堵的效果,本文通过数据挖掘方法建立了一种通用评价模型。所用数据包括由北京市VMS系统和道路检测器得到的VMS历史发布信息和道路交通流数据,这些数据能够真实地反映路网中的交通状况。通过比较诱导信息和提示信息下的拥堵缓解效果,并对不同道路状况下拥堵缓解效果进行时间和空间分析。结果表明,诱导信息能够更加有效地提高拥堵路段的服务水平,特别是严重拥堵路段,诱导信息比提示信息更加有效。

  14. Congestion Pricing for Aircraft Pushback Slot Allocation.

    Science.gov (United States)

    Liu, Lihua; Zhang, Yaping; Liu, Lan; Xing, Zhiwei

    2017-01-01

    In order to optimize aircraft pushback management during rush hour, aircraft pushback slot allocation based on congestion pricing is explored while considering monetary compensation based on the quality of the surface operations. First, the concept of the "external cost of surface congestion" is proposed, and a quantitative study on the external cost is performed. Then, an aircraft pushback slot allocation model for minimizing the total surface cost is established. An improved discrete differential evolution algorithm is also designed. Finally, a simulation is performed on Xinzheng International Airport using the proposed model. By comparing the pushback slot control strategy based on congestion pricing with other strategies, the advantages of the proposed model and algorithm are highlighted. In addition to reducing delays and optimizing the delay distribution, the model and algorithm are better suited for use for actual aircraft pushback management during rush hour. Further, it is also observed they do not result in significant increases in the surface cost. These results confirm the effectiveness and suitability of the proposed model and algorithm.

  15. Dynamic congestion control mechanisms for MPLS networks

    Science.gov (United States)

    Holness, Felicia; Phillips, Chris I.

    2001-02-01

    Considerable interest has arisen in congestion control through traffic engineering from the knowledge that although sensible provisioning of the network infrastructure is needed, together with sufficient underlying capacity, these are not sufficient to deliver the Quality of Service required for new applications. This is due to dynamic variations in load. In operational Internet Protocol (IP) networks, it has been difficult to incorporate effective traffic engineering due to the limited capabilities of the IP technology. In principle, Multiprotocol Label Switching (MPLS), which is a connection-oriented label swapping technology, offers new possibilities in addressing the limitations by allowing the operator to use sophisticated traffic control mechanisms. This paper presents a novel scheme to dynamically manage traffic flows through the network by re-balancing streams during periods of congestion. It proposes management-based algorithms that will allow label switched routers within the network to utilize mechanisms within MPLS to indicate when flows are starting to experience frame/packet loss and then to react accordingly. Based upon knowledge of the customer's Service Level Agreement, together with instantaneous flow information, the label edge routers can then instigate changes to the LSP route and circumvent congestion that would hitherto violate the customer contacts.

  16. Congestion control in charging of electric vehicles

    CERN Document Server

    Carvalho, Rui; Gibbens, Richard; Kelly, Frank

    2015-01-01

    The increasing penetration of electric vehicles over the coming decades, taken together with the high cost to upgrade local distribution networks, and consumer demand for home charging, suggest that managing congestion on low voltage networks will be a crucial component of the electric vehicle revolution and the move away from fossil fuels in transportation. Here, we model the max-flow and proportional fairness protocols for the control of congestion caused by a fleet of vehicles charging on distribution networks. We analyse the inequality in the charging times as the vehicle arrival rate increases, and show that charging times are considerably more uneven in max-flow than in proportional fairness. We also analyse the onset of instability, and find that the critical arrival rate is indistinguishable between the two protocols.

  17. Research on Congestion Pricing in Multimode Traffic considering Delay and Emission

    Directory of Open Access Journals (Sweden)

    Hongna Dai

    2015-01-01

    Full Text Available Rapid development of urbanization and automation has resulted in serious urban traffic congestion and air pollution problems in many Chinese cities recently. As a traffic demand management strategy, congestion pricing is acknowledged to be effective in alleviating the traffic congestion and improving the efficiency of traffic system. This paper proposes an urban traffic congestion pricing model based on the consideration of transportation network efficiency and environment effects. First, the congestion pricing problem under multimode (i.e., car mode and bus mode urban traffic network condition is investigated. Second, a traffic congestion pricing model based on bilevel programming is formulated for a dual-mode urban transportation network, in which the delay and emission of vehicles are considered. Third, an improved mathematical algorithm combining successive average method with the genetic algorithm is proposed to solve the bilevel programming problem. Finally, a numerical experiment based on a hypothetical network is performed to validate the proposed congestion pricing model and algorithm.

  18. Modeling and Analyzing Taxi Congestion Premium in Congested Cities

    Directory of Open Access Journals (Sweden)

    Changwei Yuan

    2017-01-01

    Full Text Available Traffic congestion is a significant problem in many major cities. Getting stuck in traffic, the mileage per unit time that a taxicab travels will decline significantly. Congestion premium (or so-called low-speed fare has become an increasingly important income source for taxi drivers. However, the impact of congestion premium on the taxicab market is not widely understood yet. In particular, modeling and analyzing of the taxi fare structure with congestion premium are extremely limited. In this paper, we developed a taxi price equilibrium model, in which the adjustment mechanism of congestion premium on optimizing the taxi driver’s income, balancing the supply and demand, and eventually improving the level of service in the whole taxicab market was investigated. In the final part, we provided a case study to demonstrate the feasibility of the proposed model. The results indicated that the current taxi fare scheme in Beijing is suboptimal, since the gain from the raise of congestion premium cannot compensate for the loss from the demand reduction. Conversely, the optimal fare scheme suggested by our model can effectively reduce the excessive demand and reach the supply-demand equilibrium, while keeping the stability of the driver’s income to the maximum extent.

  19. Formal Verification of Congestion Control Algorithm in VANETs

    Directory of Open Access Journals (Sweden)

    Mohamad Yusof Darus

    2013-04-01

    Full Text Available A Vehicular Ad-Hoc Networks (VANETs is the technology that uses moving cars as nodes in a network to create a mobile network. VANETs turn every participating car into a wireless router, allowing cars of each other to connect and create a network with a wide range. VANETs are developed for enhancing the driving safety and comfort of automotive users. The VANETs can provide wide variety of service such as Intelligent Transportation System (ITS e.g. safety applications. Many of safety applications built in VANETs are required real-time communication with high reliability. One of the main challenges is to avoid degradation of communication channels in dense traffic network. Many of studies suggested that appropriate congestion control algorithms are essential to provide efficient operation of the network. However, most of congestion control algorithms are not really applicable to event-driven safety messages. In this paper we propose congestion control algorithm as solution to prevent congestion in VANETs environment. We propose a complete validation method and analyse the performance of our congestion control algorithms for event-driven safety messages in difference congested scenarios. The effectiveness of the proposed congestion control algorithm is evaluated through the simulation using Veins simulator.

  20. 兰州城区道路交通拥堵的成因及治理%The Cause of Formation of Lanzhou Urban Traffic Congestion and Management

    Institute of Scientific and Technical Information of China (English)

    陈翔; 张林燕; 刘爽; 张海燕

    2012-01-01

    随着兰州市经济的高速发展和车辆保有量的急剧增加,兰州城区道路拥堵成为常态,给市民的出行和社会经济的正常运行带来了严重的影响.在研究兰州城区道路现状和路网特点的基础上,对兰州市区道路拥堵原因进行了分析,提出了城区道路交通治理的对策.%With the continuous rapidly development of economy and the rapid increase of Automobile Quantity in Lanzhou,the urban traffic is more and more worsen.The traffic problem has become the bottleneck to restrict regularly development of Lanzhou city.According to the research of urban road network characteristics of Lanzhou,the cause of formation of Lanzhou urban traffic congestion were profoundly analyzed,some useful suggestions to control Lanzhou urban traffic congestion were put forward.

  1. Water and sodium in heart failure: a spotlight on congestion.

    Science.gov (United States)

    Parrinello, Gaspare; Greene, Stephen J; Torres, Daniele; Alderman, Michael; Bonventre, Joseph Vincent; Di Pasquale, Pietro; Gargani, Luna; Nohria, Anju; Fonarow, Gregg C; Vaduganathan, Muthiah; Butler, Javed; Paterna, Salvatore; Stevenson, Lynne Warner; Gheorghiade, Mihai

    2015-01-01

    Despite all available therapies, the rates of hospitalization and death from heart failure (HF) remain unacceptably high. The most common reasons for hospital admission are symptoms related to congestion. During hospitalization, most patients respond well to standard therapy and are discharged with significantly improved symptoms. Post-discharge, many patients receive diligent and frequent follow-up. However, rehospitalization rates remain high. One potential explanation is a persistent failure by clinicians to adequately manage congestion in the outpatient setting. The failure to successfully manage these patients post-discharge may represent an unmet need to improve the way congestion is both recognized and treated. A primary aim of future HF management may be to improve clinical surveillance to prevent and manage chronic fluid overload while simultaneously maximizing the use of evidence-based therapies with proven long-term benefit. Improvement in cardiac function is the ultimate goal and maintenance of a "dry" clinical profile is important to prevent hospital admission and improve prognosis. This paper focuses on methods for monitoring congestion, and strategies for water and sodium management in the context of the complex interplay between the cardiac and renal systems. A rationale for improving recognition and treatment of congestion is also proposed.

  2. CONGESTION AS A RESULT OF SCHOOL AND SHOPPING CENTER ACTIVITY

    Directory of Open Access Journals (Sweden)

    Meike Kumaat

    2015-12-01

    Full Text Available Development of land use in public facilities such as shopping center and school gives an impact on transportation problem in Manado City, North Sulawesi.  To determine factors which have causal relationship with congestion  as a result of school and shopping center activity then it need to be assessed and studied.  Descriptive study with observational survey was used in this study. The study ran Structural Equation Modelling (SEM by using AMOS program. Estimated method was used to calculate sample size then found 300 repondents, comprised : visitors and mall managers, school visitors, parents, school managers, Public Works department, and urban planning department .The study yielded a statistically significant correlation between  school and shopping center activity with congestion s. The result  indicated that school activity was positively related to congestion with p value  at p=0,000 (p ≤ 0,05. Shopping center activity was positively related to congestion with p value  at p=0,000 (p ≤ 0,05. The closer proximity from school to shooping center will causes severe traffic congestion. The relationship between school facility with proximity was found in p value at  p=0,000 (p ≤ 0,05 . The relationship between shopping center facility with proximity was found in p value at  p= 0,020 (p ≤ 0,05. While, the relationship between proximity with congestion was p= 0,008 (p ≤ 0,05. Monastery school and Mega Mall activity were affecting congestion because a closer proximity of two facilities. This indicates that the occurence of traffic congestion in Monastery School  may be dependent on existence of  Piere Tendean road link

  3. Congestion control and routing over satellite networks

    Science.gov (United States)

    Cao, Jinhua

    Satellite networks and transmissions find their application in fields of computer communications, telephone communications, television broadcasting, transportation, space situational awareness systems and so on. This thesis mainly focuses on two networking issues affecting satellite networking: network congestion control and network routing optimization. Congestion, which leads to long queueing delays, packet losses or both, is a networking problem that has drawn the attention of many researchers. The goal of congestion control mechanisms is to ensure high bandwidth utilization while avoiding network congestion by regulating the rate at which traffic sources inject packets into a network. In this thesis, we propose a stable congestion controller using data-driven, safe switching control theory to improve the dynamic performance of satellite Transmission Control Protocol/Active Queue Management (TCP/AQM) networks. First, the stable region of the Proportional-Integral (PI) parameters for a nominal model is explored. Then, a PI controller, whose parameters are adaptively tuned by switching among members of a given candidate set, using observed plant data, is presented and compared with some classical AQM policy examples, such as Random Early Detection (RED) and fixed PI control. A new cost detectable switching law with an interval cost function switching algorithm, which improves the performance and also saves the computational cost, is developed and compared with a law commonly used in the switching control literature. Finite-gain stability of the system is proved. A fuzzy logic PI controller is incorporated as a special candidate to achieve good performance at all nominal points with the available set of candidate controllers. Simulations are presented to validate the theory. An effocient routing algorithm plays a key role in optimizing network resources. In this thesis, we briefly analyze Low Earth Orbit (LEO) satellite networks, review the Cross Entropy (CE

  4. EVALUATION OF THE EFFECT OF VMS IN REDUCING CONGESTION USING AIMSUN TOOL: A CASE STUDY OF ARTERIAL ROAD NETWORKS WITHIN THE CBD OF KADUNA

    Directory of Open Access Journals (Sweden)

    Aminu Shinkafi Bature

    2016-06-01

    Full Text Available Microscopic simulation of traffic on the road network within the CBD of Kaduna in Nigeria (10°31’23’’N and 7°26’25’’E was carried out using AIMSUN tool to investigate the extent to which variable message signs (VMS displaying rerouting can improve the perennial congestion without modifying the existing roadways of the city as obtained from the Google Map. Do Nothing Model representing the actual traffic condition on the arterial road networks within the CBD of the city and a VMS Rerouting model representing the behaviour of traffic when VMS displayed rerouting due to congestion were developed. Traffic state was used to develop the 2 models, using the input and turning flow vehicle demand information. Network and section statistics showing delay time and flow were generated from the models upon completion of animated and batch simulations. The results showed improvement in the network flow of the Do Nothing Model from 7732 veh/hr to 10699 veh/hr due to rerouting message conveyed by the VMS representing 38.37% improvement of the capacity of the network, while the total travel time of the network increase from 208.648 secs/km for the Do Nothing Model to 230.001 secs/km for the VMS Model representing 10.23%.

  5. Cardiomyopathy and right-sided congestive heart failure in a red-tailed hawk (Buteo jamaicensis).

    Science.gov (United States)

    Knafo, S Emmanuelle; Rapoport, Gregg; Williams, Jamie; Brainard, Benjamin; Driskell, Elizabeth; Uhl, Elizabeth; Crochik, Sonia; Divers, Stephen J

    2011-03-01

    A 15-year-old female red-tailed hawk (Buteo jamaicensis) was evaluated because of dyspnea, anorexia, and coelomic distension. Diagnostic imaging results confirmed severe coelomic effusion and revealed a markedly dilated right ventricle. The diagnosis was right-sided congestive heart failure. Results of measurements of vitamin E, selenium, lead, zinc, and cardiac troponin levels were normal or nondiagnostic. The hawk was treated with furosemide, antifungal and antimicrobial agents, and supplemental fluids and oxygen, but euthanasia was elected because of the poor prognosis and the practical difficulties associated with intensive case management. To our knowledge, this is the first described case of cardiomyopathy and congestive heart failure in a captive red-tailed hawk.

  6. Importance of chronic obstructive pulmonary disease for prognosis and diagnosis of congestive heart failure in patients with acute myocardial infarction

    DEFF Research Database (Denmark)

    Kjøller, Erik; Køber, Lars; Iversen, Kasper

    2004-01-01

    AIMS: To evaluate the importance of chronic obstructive pulmonary disease for prognosis and diagnosis of congestive heart failure in patients with acute myocardial infarction. METHOD AND RESULTS: Prospective registration of 6669 consecutive patients admitted with infarction and screened...... in patients with acute myocardial infarction without congestive heart failure, but is also a confounding factor for the diagnosis of congestive heart failure....

  7. Demonstration of Market-Based Real-Time Electricity Pricing on a Congested Feeder

    DEFF Research Database (Denmark)

    Larsen, Emil Mahler; Pinson, Pierre; le Ray, Guillaume

    2015-01-01

    Congestion management can delay grid reinforcements needed due to the growth of distributed technologies like photovoltaics and electric vehicles. This paper presents a method of congestion management for low voltage feeders using indirect control from the smart grid demonstration EcoGrid EU, where...... five minute electricity pricing is sent to demand. A method for forecasting demand and generating prices in a market framework is presented, and a novel mechanism to ensure prices are fair to customers who can and cannot participate is developed. The proposed market is currently being used to send...... prices to 1900 houses, with a virtual feeder of 28 houses receiving congestion pricing. Simulations are used to calculate the cost from using this congestion management method, while demonstration results indicate that congestion can be managed successfully....

  8. Air traffic management evaluation tool

    Science.gov (United States)

    Sridhar, Banavar (Inventor); Sheth, Kapil S. (Inventor); Chatterji, Gano Broto (Inventor); Bilimoria, Karl D. (Inventor); Grabbe, Shon (Inventor); Schipper, John F. (Inventor)

    2012-01-01

    Methods for evaluating and implementing air traffic management tools and approaches for managing and avoiding an air traffic incident before the incident occurs. A first system receives parameters for flight plan configurations (e.g., initial fuel carried, flight route, flight route segments followed, flight altitude for a given flight route segment, aircraft velocity for each flight route segment, flight route ascent rate, flight route descent route, flight departure site, flight departure time, flight arrival time, flight destination site and/or alternate flight destination site), flight plan schedule, expected weather along each flight route segment, aircraft specifics, airspace (altitude) bounds for each flight route segment, navigational aids available. The invention provides flight plan routing and direct routing or wind optimal routing, using great circle navigation and spherical Earth geometry. The invention provides for aircraft dynamics effects, such as wind effects at each altitude, altitude changes, airspeed changes and aircraft turns to provide predictions of aircraft trajectory (and, optionally, aircraft fuel use). A second system provides several aviation applications using the first system. Several classes of potential incidents are analyzed and averted, by appropriate change en route of one or more parameters in the flight plan configuration, as provided by a conflict detection and resolution module and/or traffic flow management modules. These applications include conflict detection and resolution, miles-in trail or minutes-in-trail aircraft separation, flight arrival management, flight re-routing, weather prediction and analysis and interpolation of weather variables based upon sparse measurements. The invention combines these features to provide an aircraft monitoring system and an aircraft user system that interact and negotiate changes with each other.

  9. Endogenous scheduling preferences and congestion

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Small, Kenneth

    2010-01-01

    Dynamic models of congestion so far rely on exogenous scheduling preferences of travelers, based for example on disutility of deviation from a preferred departure or arrival time for a trip. This paper provides a more fundamental view in which travelers derive utility just from consumption...... and leisure, but agglomeration economies at home and at work lead to scheduling preferences forming endogenously. Using bottleneck congestion technology, we obtain an equilibrium queuing pattern consistent with a general version of the Vickrey bottleneck model. However, the policy implications are different....... Compared to the predictions of an analyst observing untolled equilibrium and taking scheduling preferences as exogenous, we find that both the optimal capacity and the marginal external cost of congestion have changed. The benefits of tolling are greater, and the optimal time varying toll is different....

  10. Air congestion delay: a review

    Directory of Open Access Journals (Sweden)

    Daniel Alberto Pamplona

    2016-04-01

    Full Text Available This article is a literature review of the air congestion delay and its costs. Air congestion is a worldwide problem. Its existence brings costs for airlines and discomfort for passengers. With the increasing demand for air transport, the study of air congestion has attracted the attention of many researchers around the world. The cause for the delays is erroneously attributed only to the lack of infrastructure investments. The literature review shows that other factors such as population growth, increasing standards of living, lack of operational planning and environmental issues exercise decisive influence. Several studies have been conducted in order to analyze and propose solutions to this problem that affects society as a whole.

  11. Congestion Control Mechanism for Intermittently Connected Wireless Network

    Directory of Open Access Journals (Sweden)

    Ruyan Wang

    2016-01-01

    Full Text Available Based on the “storing-carrying-forwarding” transmission manner, the packets are forwarded flexibly in Intermittently Connected Wireless Network (ICWN. However, due to its limited resources, ICWN can easily become congested as a large number of packets entering into it. In such situation, the network performance is seriously deteriorated. To solve this problem, we propose a congestion control mechanism that is based on the network state dynamic perception. Specifically, through estimating the congestion risk when a node receives packets, ICWN can reduce the probability of becoming congested. Moreover, due to ICWN’s network dynamics, we determine the congestion risk threshold by jointly taking into account the average packet size, average forwarding risk, and available buffer resources. Further, we also evaluate the service ability of a node in a distributed manner by integrating the recommendation information from other intermediate nodes. Additionally, a node is selected as a relay node according to both the congestion risk and service ability. Simulation results show that the network performance can be greatly optimized by reducing the overhead of packet forwarding.

  12. Patent ductus arteriosus in an adult cat with pulmonary hypertension and right-sided congestive heart failure: hemodynamic evaluation and clinical outcome following ductal closure.

    Science.gov (United States)

    Novo-Matos, José; Hurter, Karin; Bektas, Rima; Grest, Paula; Glaus, Tony

    2014-09-01

    Right-sided congestive heart failure (CHF) developed secondary to severe pulmonary hypertension (PH) in an 8-year-old cat with a left-to-right shunting patent ductus arteriosus (PDA). Vascular reactivity was tested prior to shunt ligation by treatment with oxygen and sildenafil. This treatment was associated with a significant decrease in pulmonary artery pressure as assessed by echocardiography. Subsequently surgical shunt ligation was planned. During thoracotomy, digital occlusion of the PDA was performed for 10 min with simultaneous catheter measurement of right ventricular pressure, which did not increase. Permanent shunt ligation resulted in a complete and sustained clinical recovery. A lung biopsy sample obtained during thoracotomy demonstrated histopathological arterial changes typical of PH. Cats can develop clinically severe PH and right-sided CHF secondary to a left-to-right PDA even at an advanced age. Assuming there is evidence of pulmonary reactivity, PDA occlusion might be tolerated and can potentially produce long-term clinical benefits.

  13. Endogenous scheduling preferences and congestion

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Small, Kenneth

    2010-01-01

    Dynamic models of congestion so far rely on exogenous scheduling preferences of travelers, based for example on disutility of deviation from a preferred departure or arrival time for a trip. This paper provides a more fundamental view in which travelers derive utility just from consumption...... and leisure, but agglomeration economies at home and at work lead to scheduling preferences forming endogenously. Using bottleneck congestion technology, we obtain an equilibrium queuing pattern consistent with a general version of the Vickrey bottleneck model. However, the policy implications are different...

  14. Congestion Avoidance in IP Based CDMA Radio Access Network

    Directory of Open Access Journals (Sweden)

    Syed Shakeel Hashmi

    2011-02-01

    Full Text Available CDMA is an important air interface technologies for cellular wireless networks. As CDMAbasedcellular networks mature, the current point-to-point links will evolve to an IP-based Radio AccessNetwork (RAN. mechanisms must be designed to control the IP Radio Access Network congestion.This Paper implements a congestion control mechanism using Router control and channelcontrol method for IP-RAN on CDMA cellular network. The Router control mechanism uses the featuresof CDMA networks using active Queue Management technique to reduce delay and to minimize thecorrelated losses. The Random Early Detection Active Queue Management scheme (REDAQM is to berealized for the router control for data transmission over the radio network using routers as the channel.The channel control mechanism control the congestion by bifurcating the access channel into multiplelayer namely RACH, BCCH and DCH for data accessing. The proposed paper work is realized usingMatlab platform.

  15. Abstracts of Selected Management Training Evaluations.

    Science.gov (United States)

    Gast, Ilene

    Intended for evaluators--whether trainers, psychologists, management consultants or professors--this bibliography samples findings in management training evaluation between 1953 and 1975. It contains 28 abstracts of representative articles from journals in applied psychology and personnel management. Each abstract is a one-half to one-page…

  16. ENDOGENOUS SCHEDULING PREFERENCES AND CONGESTION

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Small, Kenneth

    2017-01-01

    We consider the timing of activities through a dynamic model of commuting with congestion, in which workers care solely about leisure and consumption. Implicit preferences for the timing of the commute form endogenously due to temporal agglomeration economies. Equilibrium exists uniquely and is i...

  17. Congestion and residential moving behaviour

    DEFF Research Database (Denmark)

    Larsen, Morten Marott; Pilegaard, Ninette; Van Ommeren, Jos

    2008-01-01

    we study how congestion and residential moving behaviour are interrelated, using a two-region job search model. Workers choose between interregional commuting and residential moving, in order to live closer to their place of work. This choice affects the external costs of commuting, due...

  18. Queuing and convergence properties of a dynamic assignment model for congested networks

    NARCIS (Netherlands)

    Troost, J.F.; Botma, H.; Bovy, P.H.L.

    1996-01-01

    The growing congestion problems demand a new generation of traffic models that are applicable in the planning and management of infrastructure. The aim of this thesis is the development of a traffic model able to predict congestions and their influence on traffic operation. This model is meant for

  19. OPTIMAL CONGESTION CHARGES IN GENERAL EQUILIBRIUM

    Directory of Open Access Journals (Sweden)

    Dong-Joo MOON, Ph.D.

    2002-01-01

    Another maximization problem involves characterizing the second-best optimal solution. In this problem, it is assumed to impose the congestion toll only on a single highway link. This problem yields the second-best congestion toll different from the first-best one. This second-best optimal congestion toll has the structure to reflect its impact on other highway links exempt from the congestion charge program.

  20. Program Evaluation: Two Management-Oriented Samples

    Science.gov (United States)

    Alford, Kenneth Ray

    2010-01-01

    Two Management-Oriented Samples details two examples of the management-oriented approach to program evaluation. Kenneth Alford, a doctorate candidate at the University of the Cumberlands, details two separate program evaluations conducted in his school district and seeks to compare and contrast the two evaluations based upon the characteristics of…

  1. Evaluation and management of polymyositis

    Directory of Open Access Journals (Sweden)

    Kathy Hunter

    2012-01-01

    Full Text Available Polymyositis (PM is one of the inflammatory myopathies, disorders characterized pathologically by the presence of inflammatory infiltrates in striated muscle. The principal clinical manifestation of PM is proximal muscle weakness. The cause of PM is unknown, but current evidence suggests that it is an autoimmune disorder. PM can affect people of any age, but most commonly presents between the ages of 50 to 70. PM is rarely seen in people younger than 18 years of age, and is twice as common among females than males. PM is more common in blacks than in whites. The overall prevalence of PM is 1 per 100,000. Muscle weakness may develop suddenly or more insidiously over a period of weeks to months. The classic symptom of PM is proximal weakness, which may manifest as difficulty holding the arms over the head, climbing stairs, or rising from a chair. Weakness of the striated muscle of the upper esophagus may result in dysphagia, dysphonia, and aspiration. The chest wall muscles may be affected, leading to ventilatory compromises. Involvement of cardiac muscle may lead to arrhythmias and congestive heart failure. Dermatomyositis (DM is closely related to PM, and both are distinguished primarily by the occurrence of characteristic skin abnormalities in the former. PM and DM may be associated with a variety of malignancies. PM may also occur as part of the spectrum of other rheumatic diseases like systemic lupus erythematosus and mixed connective tissue disease. Moreover, inflammatory myopathy may be caused by some drugs (procainamide, D-penicillamine, and viruses, most notably the retroviruses. Corticosteroids and immunosuppressive agents are the mainstays of therapy for PM. The principal goals of therapy are to improve strength and improve physical functioning. Many patients require treatment for several years. The 5-year survival rate for treated patients is in the order of 95%. Up to one-third of PM patients may be left with some degree of residual

  2. Green supply chain management using the queuing theory to handle congestion and reduce energy consumption and emissions from supply chain transportation fleet

    National Research Council Canada - National Science Library

    Arvin Aziziankohan; Fariborz Jolai; Mohammad Khalilzadeh; Roya Soltani; Reza Tavakkoli-Moghaddam

    2017-01-01

    .... Green products are resulted from the application of green supply chain management strategies to the organizations' performance strategies, so that we can reduce environmental pollutants and wastes...

  3. TCP Congestion Control for the Networks with Markovian Jump Parameters

    Directory of Open Access Journals (Sweden)

    MOMENI, H. R.

    2011-05-01

    Full Text Available This paper is concerned with the problem of TCP congestion control for the class of communication networks with random parameters. The linear dynamic model of TCP New Reno in congestion avoidance mode is considered which contains round trip delays in both state and input. The randomness of link capacity, round trip time delay and the number of TCP sessions is modeled with a continuous-time finite state Markov process. An Active Queue Management (AQM technique is then used to adjust the queue level of the congested link to a predefined value. For this purpose, a dynamic output feedback controller with mode dependent parameters is synthesized to stochastically stabilize the TCP/AQM dynamics. The procedure of the control synthesis is implemented by solving a linear matrix inequality (LMI. The results are tested within a simulation example and the effectiveness of the proposed design method is verified.

  4. Traffic Congestion Detection System through Connected Vehicles and Big Data.

    Science.gov (United States)

    Cárdenas-Benítez, Néstor; Aquino-Santos, Raúl; Magaña-Espinoza, Pedro; Aguilar-Velazco, José; Edwards-Block, Arthur; Medina Cass, Aldo

    2016-04-28

    This article discusses the simulation and evaluation of a traffic congestion detection system which combines inter-vehicular communications, fixed roadside infrastructure and infrastructure-to-infrastructure connectivity and big data. The system discussed in this article permits drivers to identify traffic congestion and change their routes accordingly, thus reducing the total emissions of CO₂ and decreasing travel time. This system monitors, processes and stores large amounts of data, which can detect traffic congestion in a precise way by means of a series of algorithms that reduces localized vehicular emission by rerouting vehicles. To simulate and evaluate the proposed system, a big data cluster was developed based on Cassandra, which was used in tandem with the OMNeT++ discreet event network simulator, coupled with the SUMO (Simulation of Urban MObility) traffic simulator and the Veins vehicular network framework. The results validate the efficiency of the traffic detection system and its positive impact in detecting, reporting and rerouting traffic when traffic events occur.

  5. Congestion Free Routing in Adhoc Networks

    Directory of Open Access Journals (Sweden)

    V. Sankaranarayanan

    2012-01-01

    Full Text Available Problem statement: A Mobile Ad-Hoc Network (MANET is a temporary network; the mobile devices in an ad-hoc network are communicating through wireless links without any pre-existing infrastructure. The one major problem of this network is network congestion, it may take place at any intermediate nodes when data packets are traveling from source to destination. The major problems of congestion or high data loss, increasing End to End and retransmission packets which affects the overall network performance. The main goal of congestion control is to effectively utilize the existing network resources and maintain the network load below the capacity. Approach: This study presents the Congestion Free Routing in Adhoc networks (CFR, based on dynamically estimated mechanism to monitor network congestion by calculating the average queue length at the node level. While using the average queue length, the nodes’ congestion status divided into the three zones (safe zone, likely to be congested zone and congested zone. CFR utilizes the non-congested neighbors and initiates route discovery mechanism to discover a congestion free route between source and destination. This path becomes a core path between source and destination. To maintain the congestion free status, the nodes which are helping data packet transmission periodically calculate their congestion status at the node level. When a core node is noticed that it fell in to likely to congested zone and alerts to its neighbors. The predecessor core path node is aware of this situation and initiates an alternate path discovery mechanism to a destination. Finally it discovers a new congestion free route to the destination. Results: The assessment between CFR and AODV was conducted by using the Ns-2 simulator. The simulation results confirmed that the CFR improved packet delivery ratio, reduction of End to End delay and control packets. Conclusion: Our proposed technique solved the congestion problems in a

  6. Evaluating your personal management style.

    Science.gov (United States)

    Anderson, D H

    1982-01-01

    Every medical group manager develops his own managerial leadership style. This style is based on personal background and education, an individual conception of what management and leadership are, and analysis and application of management theory. The author identifies many responsibilities that an administrator must assume to effectively manage--responsibilities which are closely tied to employee motivation. Motivational theories are discussed, as well as the application of techniques based on principles. The author has also distilled what he considers to be the essential qualities of a successful management style.

  7. Uninhabited Traffic Management System Evaluator (UTME) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The key innovation of this effort is the development of an Uninhabited Aerial System (UAS) Traffic Manager Evaluator (UTME) specifically targeted at evaluating...

  8. Congestive heart failure with preserved left ventricular systolic function after acute myocardial infarction

    DEFF Research Database (Denmark)

    Møller, Jacob Eifer; Brendorp, Bente; Ottesen, Michael

    2003-01-01

    AIMS: To characterise the prevalence, in-hospital complications, management, and long-term outcome of patients with congestive heart failure but preserved left ventricular systolic function after acute myocardial infarction. METHODS: 3166 consecutive patients screened for entry in the Bucindolol...... Evaluation in Acute Myocardial Infarction Trial with definite acute myocardial infarction and echocardiographic assessment of left ventricular systolic function were included between 1998 and 1999 in this prospective observational study. Main outcome measures were occurrences of in-hospital complications...... ventricular systolic function, and is associated with increased risk of in-hospital complications and death following acute myocardial infarction....

  9. Evaluating and Selecting Sport Management Undergraduate Programs.

    Science.gov (United States)

    Cuneen, Jacquelyn; Sidwell, M. Joy

    1998-01-01

    States that the accelerated growth of sport management undergraduate programs that began in the 1980s has continued into the current decade. There are currently 180 sport management major programs in American colleges and universities. Describes the sports management approval process and suggests useful strategies to evaluate sport management…

  10. Office Financial Evaluation and Management

    OpenAIRE

    Opelka, Frank G.

    2005-01-01

    Surgeons are facing greater pressures as business entities with each passing year. With limited ability to compensate by increasing workload, surgeons must understand finances and practice management. Strategic planning for the survival of a clinical practice now requires a background in business long absent in the formal education of surgeons. This article provides an introduction to the basic principles of office finance, management, and the revenue cycle.

  11. Embolization to treat pelvic congestion syndrome and vulval varicose veins.

    NARCIS (Netherlands)

    Vleuten, C.J.M. van der; Kempen, J.A.L. van; Schultze Kool, L.J.

    2012-01-01

    OBJECTIVE: To evaluate the efficacy of embolization for treating the symptoms of pelvic congestion syndrome (PCS). METHODS: Twenty-one women with PCS who were treated with embolization at Radboud University Nijmegen Medical Centre between 2003 and 2008 were sent a questionnaire about their symptoms

  12. Congestion

    DEFF Research Database (Denmark)

    Lindegaard, Laura Bang

    of automobility unfolds as people account for and, hence, conduct their transportation practices. In this way, it unravels how villagers in a small Danish village negotiate a municipal strategy and conduct their transportation practices in ways that merely sustain the villagers’ already maintained car......The book investigates the negotiation of governmental rationalities of car-dependent life in the face of climate change. It appears that current forms of governing are bound up with a specific utilisation of the freedom of the governed. Accordingly, the book demonstrates how the governing...

  13. Urban Traffic Congestion Pricing Model with the Consideration of Carbon Emissions Cost

    Directory of Open Access Journals (Sweden)

    Jian Wang

    2014-02-01

    Full Text Available As one of the most effective traffic demand management opinions, congestion pricing can reduce private car travel demand and the associated carbon dioxide emissions. First, we summarized the status quo of transport carbon dioxide emission charges and congestion pricing, and then, we analyzed the characteristics of urban transport carbon dioxide emissions. Then, we proposed a (pricing framework in which carbon emission costs would be considered as part of the generalized cost of travel. Based on this framework, this paper developed a bi-level mathematical model to optimize consumer surplus, using congestion and carbon emission charges as the control variables. A dissect search algorithm was used to solve the bi-level program model, and a numerical example was given to illustrate the methodology. This paper incorporates the emission pricing into the congestion pricing model, while considering two modes, and puts forward suitable proposals for the implementation of an urban traffic congestion pricing policy in China.

  14. Green Supply Chain Management Using the Queuing Theory to Handle Congestion and Reduce Energy Consumption and Emissions From Supply Chain Transportation Fleet

    OpenAIRE

    Arvin Aziziankohan; Fariborz Jolai; Mohammad Khalilzadeh; Roya Soltani; Reza Tavakkoli-Moghaddam

    2017-01-01

    Purpose: Nowadays, governments and people pay more attention to use green products due to environmental pollution, irreplaceable energy and shortage of resources. Green products are resulted from the application of green supply chain management strategies to the organizations' performance strategies, so that we can reduce environmental pollutants and wastes and take a step towards saving energy with limited resources. Methodology:  In this paper, the effect of reducing energy consumption ...

  15. Estimation of Congestion in Free Disposal Hull Models Using Data Envelopment Analysis

    Directory of Open Access Journals (Sweden)

    M. Abbasi

    2014-01-01

    Full Text Available This paper deals with evaluating congestion in free disposal hull (FDH models. There are several approaches in data envelopment analysis (DEA literatures which discuss the theory and application of congestion. However, almost all of these approaches considered convex DEA technologies. So, in the case of nonconvex technologies, including FDH technology, this field is almost nil. This paper makes an attempt to fill in this void. To do so, this study provides a pairwise comparisons-based algorithm to evaluate congestion in FDH model. This algorithm identifies the sources of congestion and estimates its amounts. It is also capable of detecting the losses amounts of output due to congestion. The validity of the proposed model is demonstrated using some numerical and empirical examples.

  16. Scalable Deep Traffic Flow Neural Networks for Urban Traffic Congestion Prediction

    OpenAIRE

    Fouladgar, Mohammadhani; Parchami, Mostafa; Elmasri, Ramez; Ghaderi, Amir

    2017-01-01

    Tracking congestion throughout the network road is a critical component of Intelligent transportation network management systems. Understanding how the traffic flows and short-term prediction of congestion occurrence due to rush-hour or incidents can be beneficial to such systems to effectively manage and direct the traffic to the most appropriate detours. Many of the current traffic flow prediction systems are designed by utilizing a central processing component where the prediction is carri...

  17. Road traffic congestion a concise guide

    CERN Document Server

    Falcocchio, John C

    2015-01-01

    This book on road traffic congestion in cities and suburbs describes congestion problems and shows how they can be relieved. The first part (Chapters 1 - 3) shows how congestion reflects transportation technologies and settlement patterns. The second part (Chapters 4 - 13) describes the causes, characteristics, and consequences of congestion. The third part (Chapters 14 - 23) presents various relief strategies - including supply adaptation and demand mitigation - for nonrecurring and recurring congestion. The last part (Chapter 24) gives general guidelines for congestion relief and provides a general outlook for the future. The book will be useful for a wide audience - including students, practitioners and researchers in a variety of professional endeavors: traffic engineers, transportation planners, public transport specialists, city planners, public administrators, and private enterprises that depend on transportation for their activities.  

  18. Evaluating Water Management Practice for Sustainable Mining

    Directory of Open Access Journals (Sweden)

    Xiangfeng Zhang

    2014-02-01

    Full Text Available To move towards sustainable development, the mining industry needs to identify better mine water management practices for reducing raw water use, increasing water use efficiency, and eliminating environmental impacts in a precondition of securing mining production. However, the selection of optimal mine water management practices is technically challenging due to the lack of scientific tools to comprehensively evaluate management options against a set of conflicting criteria. This work has provided a solution to aid the identification of more sustainable mine water management practices. The solution includes a conceptual framework for forming a decision hierarchy; an evaluation method for assessing mine water management practices; and a sensitivity analysis in view of different preferences of stakeholders or managers. The solution is applied to a case study of the evaluation of sustainable water management practices in 16 mines located in the Bowen Basin in Queensland, Australia. The evaluation results illustrate the usefulness of the proposed solution. A sensitivity analysis is performed according to preference weights of stakeholders or managers. Some measures are provided for assessing sensitivity of strategy ranking outcomes if the weight of an indicator changes. Finally, some advice is given to improve the mine water management in some mines.

  19. A Bathtub Model of Traffic Congestion

    OpenAIRE

    Arnott, Richard

    2011-01-01

    In the standard economic models of traffic congestion, traffic flow does not fall under heavily congested conditions. But this is counter to experience, especially in thedowntown areas of most major cities during rush hour. This paper presents a bathtub model of traffic congestion. The height of water in the bathtub corresponds totraffic density, velocity is negatively related to density, and outflow is the product of density and velocity. Above a critical density, outflow falls as density in...

  20. Test and Evaluation Management Guide

    Science.gov (United States)

    1993-08-01

    requirements and specifications of the contract. (2) Identify operational deficiencies; Postproduction testing requirements may (3) Recommend and evaluate...objectives to evaluateTHE PRODUCTION AND DE PRODMENTIOHAND postproduction logistics readiness and sup- DEPLOYMENT PHASE port are to:(MS III to MS IV) After...does, however, in- grated Logistics Support Plan (ILSP), etc.) clude a requirement for postproduction that are also in early stages of develop- test

  1. evaluation of municipal solid waste management system

    African Journals Online (AJOL)

    eobe

    management facility gave a significant fitted model to show the relationship between household's ... However most of these studies tend not to evaluate ... On the other hand, some residents .... most dominant category of house type (54%) and.

  2. Assessment of network traffic congestion through Traffic Congestability Value (TCV): a new index

    OpenAIRE

    Patel Nilanchal; Mukherjee Alok Bhushan

    2015-01-01

    Traffic congestion is a major and growing problem in urban areas across the globe. It reduces the effective spatial interaction between different locations. To mitigate traffic congestion, not only the actual status of different routes needs to be known but also it is imperative to determine network congestion in different spatial zones associated with distinct land use classes. In the present paper, a new formula is proposed to quantify traffic congestion in the different spatial zones of a ...

  3. Economic value evaluation in disease management programs.

    Science.gov (United States)

    Magnezi, Racheli; Reicher, Sima; Shani, Mordechai

    2008-05-01

    Chronic disease management has been a rapidly growing entity in the 21st century as a strategy for managing chronic illnesses in large populations. However, experience has shown that disease management programs have not been able to demonstrate their financial value. The objectives of disease management programs are to create quality benchmarks, such as principles and guidelines, and to establish a uniform set of metrics and a standardized methodology for evaluating them. In order to illuminate the essence of disease management and its components, as well as the complexity and the problematic nature of performing economic calculations of their profitability and value, we collected data from several reports that dealt with the economic intervention of disease management programs. The disease management economic evaluation is composed of a series of steps, including the following major categories: data/information technology, information generation, assessment/recommendations, actionable customer plans, and program assessment/reassessment. We demonstrate the elements necessary for economic analysis. Disease management is one of the most innovative tools in the managed care environment and is still in the process of being defined. Therefore, objectives should include the creation of quality measures, such as principles and guidelines, and the establishment of a uniform set of metrics and a standardized methodology for evaluating them.

  4. AN EFFECTIVE NETWORK CONGESTION CONTROL METHOD FOR MULTILAYER NETWORK

    Institute of Scientific and Technical Information of China (English)

    Du Haifeng; Xiao Yang; Lu Lingyun

    2008-01-01

    The congestion control problem in a single node network has been solved by the nonlinear feedback control method, which has been proven to be effective and robust for different router's queue size. However, these control models are based on the single layer network architecture, and the senders and receivers are directly connected by one pair of routers. With the network architecture being more and more complex, it is a serious problem how to cooperate many routers working in the multilayer network simultaneously. In this paper, an effective Active Queue Management (AQM) scheme to guarantee the stability by the nonlinear control of imposing some restrictions on AQM parameter in multilayer network is proposed. The nonlinear control can rely on some heuristics and network traffic controllers that appear to be highly correlated with the multilayer network status. The proposed method is based on the improved classical Random Early Detection (RED) differential equation and a theorem for network congestion control. The theorem proposed in the paper proved that the stability of the fluid model can effectively ensure the convergence of the average rate to its equilibrium point through many routers in multilayer network. Moreover, when the network capacity is larger, the proposed scheme can still approach to the fullest extensibility of utilization and ensure the stability of the fluid model. The paper reveals the reasons of congestion control in multilayer network, provides a theorem for avoiding network congestion, and gives simulations to verify the results.

  5. Xamoterol in severe congestive heart failure

    DEFF Research Database (Denmark)

    Tangø, M; Lyngborg, K; Mehlsen, J;

    1992-01-01

    Twelve patients in severe congestive heart failure were given placebo, 100 mg xamoterol (Corwin) twice daily and 200 mg xamoterol twice daily, respectively, in 3 two-week periods in a double-blind randomised study. At the end of each treatment period the patients were evaluated. No differences were...... found between placebo and xamoterol in the following parameters: New York Heart Association function group index, heart volume, body weight, exercise duration on bicycle and treadmill, heart rate and systolic and diastolic blood pressure at rest. However, during exercise we found significantly lower...... heart rate and rate-pressure product during xamoterol treatment. This reduction is probably indicating occupation of beta-adrenoreceptors with concomitant reduced oxygen consumption during exercise....

  6. Scheduling and congestion control for wireless internet

    CERN Document Server

    Wang, Xin

    2014-01-01

    This brief proposes that the keys to internet cross-layer optimization are the development of non-standard implicit primal-dual solvers for underlying optimization problems, and design of jointly optimal network protocols as decomposition of such solvers. Relying on this novel design-space oriented approach, the author develops joint TCP congestion control and wireless-link scheduling schemes for wireless applications over Internet with centralized and distributed (multi-hop) wireless links. Different from the existing solutions, the proposed schemes can be asynchronously implemented without message passing among network nodes; thus they are readily deployed with current infrastructure. Moreover, global convergence/stability of the proposed schemes to optimal equilibrium is established using the Lyapunov method in the network fluid model. Simulation results are provided to evaluate the proposed schemes in practical networks.

  7. Relationship Between Carbon Dioxide Levels and Reported Congestion and Headaches on the International Space Station

    Science.gov (United States)

    Cole, Robert; Wear, Mary; Young, Millennia; Cobel, Christopher; Mason, Sara

    2017-01-01

    Congestion is commonly reported during spaceflight, and most crewmembers have reported using medications for congestion during International Space Station (ISS) missions. Although congestion has been attributed to fluid shifts during spaceflight, fluid status reaches equilibrium during the first week after launch while congestion continues to be reported throughout long duration missions. Congestion complaints have anecdotally been reported in relation to ISS CO2 levels; this evaluation was undertaken to determine whether or not an association exists. METHODS: Reported headaches, congestion symptoms, and CO2 levels were obtained for ISS expeditions 2-31, and time-weighted means and single-point maxima were determined for 24-hour (24hr) and 7-day (7d) periods prior to each weekly private medical conference. Multiple imputation addressed missing data, and logistic regression modeled the relationship between probability of reported event of congestion or headache and CO2 levels, adjusted for possible confounding covariates. The first seven days of spaceflight were not included to control for fluid shifts. Data were evaluated to determine the concentration of CO2 required to maintain the risk of congestion below 1% to allow for direct comparison with a previously published evaluation of CO2 concentrations and headache. RESULTS: This study confirmed a previously identified significant association between CO2 and headache and also found a significant association between CO2 and congestion. For each 1-mm Hg increase in CO2, the odds of a crew member reporting congestion doubled. The average 7-day CO2 would need to be maintained below 1.5 mmHg to keep the risk of congestion below 1%. The predicted probability curves of ISS headache and congestion curves appear parallel when plotted against ppCO2 levels with congestion occurring at approximately 1mmHg lower than a headache would be reported. DISCUSSION: While the cause of congestion is multifactorial, this study showed

  8. Mitigating Congestion in a Power System and Role of FACTS Devices

    Directory of Open Access Journals (Sweden)

    Madhvi Gupta

    2017-01-01

    Full Text Available Congestion management refers to avoiding or relieving congestion. In transmission lines, congestion management is one of the most important issues for the reliable operation of power system in the deregulated environment. Restructuring has brought considerable changes in all possible domains including electric supply industry. By virtue of restructuring, electricity has now become a commodity and has converted into a deregulated one. The traditional regulated power system has now become a competitive power market. In the present scenario, the real time transmission congestion is the operating condition in which the transfer capability to implement all the traded transactions simultaneously is not enough due to either some expected contingencies or market settlement. Thus, congestion is associated with one or more violations of the physical, operational, and policy constraints under which grids operate. Thus, congestion management is about managing the power transmission and distribution among valuable consumers priority-wise. Placement of FACTS (Flexible Alternating Current Transmission System devices for generation rescheduling and load-shedding play a crucial role in congestion management. FACTS devices are used to enhance the maximum load ability of the transmission system. FACTS increases the flexibility of power system, makes it more controllable, and allows utilization of existing network closer to its thermal loading capacity without jeopardizing the stability. FACTS technology can boost the transfer capability in stability limited systems by 20–30%. As a result, more power can reach consumers with a shorter project implementation time and a lower investment cost. This review work unites the various publications on congestion management in past few decades.

  9. [Evaluation model for municipal health planning management].

    Science.gov (United States)

    Berretta, Isabel Quint; Lacerda, Josimari Telino de; Calvo, Maria Cristina Marino

    2011-11-01

    This article presents an evaluation model for municipal health planning management. The basis was a methodological study using the health planning theoretical framework to construct the evaluation matrix, in addition to an understanding of the organization and functioning designed by the Planning System of the Unified National Health System (PlanejaSUS) and definition of responsibilities for the municipal level under the Health Management Pact. The indicators and measures were validated using the consensus technique with specialists in planning and evaluation. The applicability was tested in 271 municipalities (counties) in the State of Santa Catarina, Brazil, based on population size. The proposed model features two evaluative dimensions which reflect the municipal health administrator's commitment to planning: the guarantee of resources and the internal and external relations needed for developing the activities. The data were analyzed using indicators, sub-dimensions, and dimensions. The study concludes that the model is feasible and appropriate for evaluating municipal performance in health planning management.

  10. Web-based Projects Evaluation Management System

    Directory of Open Access Journals (Sweden)

    S. Al-Zoubi

    2008-01-01

    Full Text Available This project designs a Web-based evaluation management system for the College of Arts and Sciences (CAS. Problem statement: The Msc students in College of Arts and Sciences (CAS in applied sciences had to take their final project as a project paper in order to fulfill the requirements of their programs and be able to graduate. The final project was evaluated in two parts; first part is representing 40% of the total mark and evaluated by evaluators. Second part was representing 60% of the total mark and evaluated by the student's supervisor. These evaluation were done manually. Both the evaluators and supervisors had to fill in the evaluation forms manually and submit them to the office. Approach: The design research methodology or sometimes called "improvement research" contained the major steps: Awareness the problem, suggestion, development, evaluation and conclusion. Results: Both evaluators and supervisors can fill in the evaluation forms through the Internet. Bring the advantage of saving time and resources over traditional paper and pencil scan sheet method. For enhancing the performance of current final project evaluation process in College of Arts and Sciences (CAS this study proposed a web based evaluation management system to replace the current paper forms used by the evaluators and supervisors. Conclusion: Implementing this system will enable the evaluation results to be entered, presume and retrieved anytime anywhere.

  11. Acute bronchitis: Evaluation and management.

    Science.gov (United States)

    Blush, Raymond R

    2013-10-10

    Acute bronchitis affects millions of individuals, significantly impacting patient health and the healthcare industry. Understanding evaluation and treatment guidelines for acute bronchitis allows the nurse practitioner to practice comprehensive care for patients. This article reviews evidence-based practices when caring for the patient with acute bronchitis, promoting optimization of healthy outcomes.

  12. Fluid Volume Overload and Congestion in Heart Failure: Time to Reconsider Pathophysiology and How Volume Is Assessed.

    Science.gov (United States)

    Miller, Wayne L

    2016-08-01

    Volume regulation, assessment, and management remain basic issues in patients with heart failure. The discussion presented here is directed at opening a reassessment of the pathophysiology of congestion in congestive heart failure and the methods by which we determine volume overload status. Peer-reviewed historical and contemporary literatures are reviewed. Volume overload and fluid congestion remain primary issues for patients with chronic heart failure. The pathophysiology is complex, and the simple concept of intravascular fluid accumulation is not adequate. The dynamics of interstitial and intravascular fluid compartment interactions and fluid redistribution from venous splanchnic beds to central pulmonary circulation need to be taken into account in strategies of volume management. Clinical bedside evaluations and right heart hemodynamic assessments can alert clinicians of changes in volume status, but only the quantitative measurement of total blood volume can help identify the heterogeneity in plasma volume and red blood cell mass that are features of volume overload in patients with chronic heart failure and help guide individualized, appropriate therapy-not all volume overload is the same. © 2016 American Heart Association, Inc.

  13. Applying Knowledge Management in Teacher Evaluation Systems

    Science.gov (United States)

    Essandoh, Albert

    2013-01-01

    Teacher evaluations are underused in public schools, resulting in the loss of knowledge critical to professional development. Knowledge management (KM) theory offers approaches that can lead to improvements in the effectiveness of evaluations and teacher performance. This multiple case study of 9 campuses in an exemplary school district…

  14. Applying Knowledge Management in Teacher Evaluation Systems

    Science.gov (United States)

    Essandoh, Albert

    2013-01-01

    Teacher evaluations are underused in public schools, resulting in the loss of knowledge critical to professional development. Knowledge management (KM) theory offers approaches that can lead to improvements in the effectiveness of evaluations and teacher performance. This multiple case study of 9 campuses in an exemplary school district…

  15. Congestive cardiomyopathy and left ventricular thrombus.

    Science.gov (United States)

    Gould, L; Gopalaswamy, C; Chandy, F; Kim, B S

    1983-07-01

    A left ventricular thrombus was detected by echocardiography in a 54-year-old man with congestive cardiomyopathy. With the use of anticoagulants, the thrombus completely disappeared. Patients with congestive cardiomyopathy who are at high risk for thrombus formation should be screened with two-dimensional echocardiography. If a thrombus is recognized, anticoagulation therapy can then be instituted.

  16. Congestion Prediction Algorithm for Network on Chip

    Directory of Open Access Journals (Sweden)

    Hua Cai

    2013-07-01

    Full Text Available Network on chip (NoC traffic congestion was one of the important reasons for the data transmission performance degradation. In this paper, we presented a congestion judgment algorithm, which was based on neural network. The congestion control algorithm firstly used the hamming network to compute the NoC’s link buffer congestion state, secondly used the competitive network to find the worst congestion node, and then adopted avoiding congested node  routing policy to improve the NoC’s transmission performance. In this paper, the congestion control algorithm can make the data stream as far as possible evenly distributed in the NoC’s nodes and links and reduce the transmission resource competition. The simulation results showed that the congestion control algorithm could achieve better network throughput and average transmission delay.

  17. Congestion in Europe: Measurements, spatial patterns, policies

    NARCIS (Netherlands)

    Bovy, P.H.L.; Salomon, I.

    1998-01-01

    The paper addresses the road traffic congestion issue from a Western-European perspective. A view is given on factors causing trends in its temporal and spatial distribution. A discussion is presented on the difficulties encountered in measuring the levels and extent of congestion. Based on the few

  18. Surgery of congestive heart failure - the role of computed tomography in the pre- and postsurgical diagnostic evaluation; Chirurgie der Herzinsuffizienz - Stellenwert der Computertomographie in der prae- und postoperativen Diagnostik

    Energy Technology Data Exchange (ETDEWEB)

    Lembcke, A.; Kivelitz, D.E.; Rogalla, P.; Dewey, M.; Klessen, C.; Hamm, B.; Enzweiler, C.N.H. [Inst. fuer Radiologie, Charite - Universitaetsmedizin Berlin, Charite Campus Mitte, Berlin (Germany); Dohmen, P.M.; Konertz, W.F. [Klinik fuer Kardiovaskulaere Chirurgie, Charite - Universitaetsmedizin Berlin, Charite Campus Mitte, Berlin (Germany); Wiese, T.H. [Inst. fuer Radiologie, Augusta-Kranken-Anstalt, Bochum (Germany)

    2005-07-01

    The treatment of advanced, drug resistant congestive heart failure gains in importance in the field of cardiac surgery. Cardiac imaging for preoperative assessment and follow-up focuses on the determination of ventricular volumes and function as well as on the detection of postoperative complications. Computed tomography (CT) is highly accurate irrespective of the individual patient's anatomic situation, has a low examiner dependence and short examination time, does not require an arterial vascular access and can be performed in patients with metal implants. CT is the modality of choice in the follow-up of heart transplants to detect extracardiac and cardiac complications including coronary calcifications as an early sign of transplant vasculopathy. In addition, CT visualizes the elements of mechanical assist devices and can identify their possible local cardiac and mediastinal complications CT can detect fibrolipomatous involution of the mobilized muscle flap in dynamic cardiomyoplasty and can depict fibrous reactions along the epicardial mesh implant in passive cardiac containment. Further indications include assessment of typical local postoperative complications, such as intrathoracic infection and mediastinal bleeding, intracardiac thrombus formation or pericardial effusion. CT is routinely used for evaluating bypass patency but is limited in assessing associated valve defects since it does not visualize flow. (orig.)

  19. Evaluation and Management of Vaginitis

    Science.gov (United States)

    Carr, Phyllis L; Felsenstein, Donna; Friedman, Robert H

    1998-01-01

    OBJECTIVE To evaluate recent advances in our understanding of the clinical relevance, diagnosis, and treatment of vaginal infections, and to determine an efficient and effective method of evaluating this clinical problem in the outpatient setting. DATA SOURCES Relevant papers on vaginitis limited to the English language obtained through a MEDLINE search for the years 1985 to 1997 were reviewed. DATA SYNTHESIS Techniques that enable the identification of the various strains of candida have helped lead to a better understanding of the mechanisms of recurrent candida infection. From this information a rationale for the treatment of recurrent disease can be developed. Bacterial vaginosis has been associated with complications, including upper genital tract infection, preterm delivery, and wound infection. Women undergoing pelvic surgery, procedures in pregnancy, or pregnant women at risk of preterm delivery should be evaluated for bacterial vaginosis to decrease the rate of complications associated with this condition. New, more standardized criteria for the diagnosis of bacterial vaginosis may improve diagnostic consistency among clinicians and comparability of study results. Use of topical therapies in the treatment of bacterial vaginosis are effective and associated with fewer side effects than systemic medication. Trichomonas vaginalis, although decreasing in incidence, has been associated with upper genital tract infection. Therapy of T. vaginalis infection has been complicated by an increasing incidence of resistance to metronidazole. CONCLUSIONS Vaginitis is a common medical problem in women that is associated with significant morbidity and previously unrecognized complications. Research in recent years has improved diagnostic tools as well as treatment modalities for all forms of vaginitis. PMID:9613891

  20. Bisoprolol for congestive heart failure

    DEFF Research Database (Denmark)

    Rosenberg, J.; Gustafsson, F.

    2008-01-01

    Background: beta-Blockers are a cornerstone in the treatment of systolic heart failure treatment, but not all beta-blockers are effective or in this setting. Objective: To define the role of bisoprolol, a highly selective beta(1)-antagonist in congestive heart failure due to systolic dysfunction....... Methods: Using the keywords 'bisoprolol' and 'heart failure' PubMed and BIOSIS databases were searched for information regarding pharmacology and relevant randomised clinical trials. Supplementary publications were acquired by scrutinising reference lists of relevant papers. Additional information...... was obtained from the FDA website. Conclusion: Bisoprolol is an effective and well-tolerated first-line beta-blocker for patients with systolic heart failure. The knowledge is primarily based on study patients with moderate-to-severe heart failure from the three CIBIS trials Udgivelsesdato: 2008/2...

  1. Assessment of network traffic congestion through Traffic Congestability Value (TCV: a new index

    Directory of Open Access Journals (Sweden)

    Patel Nilanchal

    2015-12-01

    Full Text Available Traffic congestion is a major and growing problem in urban areas across the globe. It reduces the effective spatial interaction between different locations. To mitigate traffic congestion, not only the actual status of different routes needs to be known but also it is imperative to determine network congestion in different spatial zones associated with distinct land use classes. In the present paper, a new formula is proposed to quantify traffic congestion in the different spatial zones of a study area characterized by distinct land use classes. The proposed formula is termed the Traffic Congestability Value (TCV. The formula considers three major influencing factors: congestion index value, pedestrian movement and road surface conditions; since these parameters are significantly related to land use in a region. The different traffic congestion parameters, i.e. travel time, average speed and the proportion of time stopped, were collected in real time. Lower values of TCV correspond to a higher degree of congestion in the respective spatial zones and vice-versa and the results were validated in the field. TCV differs from the previous approaches to quantifying traffic congestion since it focuses on the causes of network congestion while in previous works the focus was generally on link flow congestion.

  2. Evaluation and management of galactorrhea.

    Science.gov (United States)

    Huang, Wenyu; Molitch, Mark E

    2012-06-01

    Galactorrhea is commonly caused by hyperprolactinemia, especially when it is associated with amenorrhea. Hyperprolactinemia is most often induced by medication or associated with pituitary adenomas or other sellar or suprasellar lesions. Less common causes of galactorrhea include hypothyroidism, renal insufficiency, pregnancy, and nipple stimulation. After pathologic nipple discharge is ruled out, patients with galactorrhea should be evaluated by measurement of their prolactin level. Those with hyperprolactinemia should have pregnancy ruled out, and thyroid and renal function assessed. Brain magnetic resonance imaging should be performed if no other cause of hyperprolactinemia is found. Patients with prolactinomas are usually treated with dopamine agonists (bromocriptine or cabergoline); surgery or radiation therapy is rarely required. Medications causing hyperprolactinemia should be discontinued or replaced with a medication from a similar class with lower potential for causing hyperprolactinemia. Normoprolactinemic patients with idiopathic, nonbothersome galactorrhea can be reassured and do not need treatment; however, those with bothersome galactorrhea usually respond to a short course of a low-dose dopamine agonist.

  3. Scheduled Controller Design of Congestion Control Considering Network Resource Constraints

    Science.gov (United States)

    Naito, Hiroyuki; Azuma, Takehito; Fujita, Masayuki

    In this paper, we consider a dynamical model of computer networks and derive a synthesis method for congestion control. First, we show a model of TCP/AQM (Transmission Control Protocol/Active Queue Management) as a dynamical model of computer networks. The dynamical model of TCP/AQM networks consists of models of TCP window size, queue length and AQM mechanisms. Second, we propose to describe the dynamical model of TCP/AQM networks as linear systems with self-scheduling parameters, which also depend on information delay. Here we focus on the constraints on the maximum queue length and TCP window-size, which are the network resources in TCP/AQM networks. We derive TCP/AQM networks as the LPV system (linear parameter varying system) with information delay and self-scheduling parameter. We design a memoryless state feedback controller of the LPV system based on a gain-scheduling method. Finally, the effectiveness of the proposed method is evaluated by using MATLAB and the well-known ns-2 (Network Simulator Ver.2) simulator.

  4. Contemporary evaluation and management of renal trauma.

    Science.gov (United States)

    Chouhan, Jyoti D; Winer, Andrew G; Johnson, Christina; Weiss, Jeffrey P; Hyacinthe, Llewellyn M

    2016-04-01

    Renal trauma occurs in approximately 1%-5% of all trauma cases. Improvements in imaging and management over the last two decades have caused a shift in the treatment of this clinical condition. A systematic search of PubMed was performed to identify relevant and contemporary articles that referred to the management and evaluation of renal trauma. Computed tomography remains a mainstay of radiological evaluation in hemodynamically stable patients. There is a growing body of literature showing that conservative, non-operative management of renal trauma is safe, even for Grade IV-V renal injuries. If surgical exploration is planned due to other injuries, a conservative approach to the kidney can often be utilized. Follow up imaging may be warranted in certain circumstances. Urinoma, delayed bleeding, and hypertension are complications that require follow up. Appropriate imaging and conservative approaches are a mainstay of current renal trauma management.

  5. Complex Evaluation Model of Corporate Energy Management

    OpenAIRE

    Ágnes Kádár Horváth

    2014-01-01

    With the ever increasing energy problems at the doorstep alongside with political, economic, social and environmental challenges, conscious energy management has become of increasing importance in corporate resource management. Rising energy costs, stricter environmental and climate regulations as well as considerable changes in the energy market require companies to rationalise their energy consumption and cut energy costs. This study presents a complex evaluation model of corporate energy m...

  6. Evaluation and management of amyotrophic lateral sclerosis.

    Science.gov (United States)

    Valadi, Nojan

    2015-06-01

    Motor neuron diseases can cause progressive impairment of voluntary muscles of movement, respiration, speech, and swallowing. This review discusses the most common motor neuron disease, amyotrophic lateral sclerosis (ALS). It reviews the evaluation, diagnosis, and management of ALS, and its epidemiology, pathophysiology, and management. A coordinated approach by the primary care physician and neurologist is necessary with a focus on treatment options, durable medical equipment needs, and end-of-life discussions. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Pattern Analysis of Driver’s “Pressure-State-Response” in Traffic Congestion

    Directory of Open Access Journals (Sweden)

    Weiwei Qi

    2013-01-01

    Full Text Available Traffic congestion, which has a direct impact on the driver’s mood and action, has become a serious problem in rush hours in most cities of China. Currently, the study about driver’s mood and action in traffic congestion is scarce, so it is necessary to work on the relationship among driver’s mood and action and traffic congestion. And the PSR (pressure-state-response framework is established to describe that relationship. Here, PSR framework is composed of a three-level logical structure, which is composed of traffic congestion environment, drivers’ physiology change, and drivers’ behavior change. Based on the PSR framework, various styles of drivers have been chosen to drive on the congested roads, and then traffic stream state, drivers’ physiology, and behavior characters have been measured via the appropriative equipment. Further, driver’s visual characteristics and lane changing characteristics are analyzed to determine the parameters of PSR framework. According to the PSR framework, the changing law of drivers’ characteristics in traffic congestion has been obtained to offer necessary logical space and systematic framework for traffic congestion management.

  8. Evaluation of Fugen core management code (POLESTAR)

    Energy Technology Data Exchange (ETDEWEB)

    Shiratori, Yoshitake (Power Reactor and Nuclear Fuel Development Corp., Tsuruga, Fukui (Japan). Fugen Nuclear Power Station); Matsumoto, Mitsuo; Deshimaru, Takehide; Saito, Kuniyoshi

    1991-06-01

    Core management code POLESTAR has been developed by PNC and it has enough functions for core management. The code has been successfully used to carry out core management of Fugen such as making a long term or next cycle fuel loading plan, predicting detailed characteristics of a next cycle core, planning of a control rod pattern and evaluating the core life time after reactor start-up and so on. This code has been contributed to the reliable and economical operation of Fugen, since its accuracy has been checked and the code has been tailored by comparing its calculation results with various measured data. (author).

  9. 大城市严重交通拥堵风险评估与应对策略%Risk Assessment & Countermeasures for Traffic Congestion in Large Metropolitan Areas

    Institute of Scientific and Technical Information of China (English)

    李锋; 陈永茂

    2011-01-01

    Because traffic congestion is becoming a bottleneck severely threatening the economic development in large cities in China,it requires immediate countermeasures than target the root of the problems. This paper first discusses the level of congestion in three aspects: technical indices of traffic engineering, travelers' tolerance, and impact area of traffic congestion. A concise evaluation method is proposed to evaluate the severity of congestions according to the scope of traffic congestion, general traffic control strategies and traffic demand management. By selecting the representative urban transportation developmcnt indexes as the key evaluation elements, this paper establishes the threshold for low,mediun and high traffic congestion levels. Based on the evaluation results, the congestion countermeasures are proposed. Finally, taking Shenzhen as an example, the paper validates the congestion assessment method as well as the corresponding congestion countermeasures.%交通拥堵日益成为制约中国大城市发展的突出问题和民生问题,迫切需要把握拥堵原因并快速采取应对措施.首先,从交通工程技术指标、出行者可接受程度以及拥堵影响范围控制角度,对严重交通拥堵进行界定.围绕结构性、一般管理及个体机动交通需求增长与管理三方面,提出一种简单明了的严重交通拥堵评估分析方法.选择城市交通发展若干具有战略性或代表性意义的指标作为评估要素,确定各评估要素产生拥堵的高、中、低三个风险等级的阈值.在此基础上,提出严重交通拥堵的应对策略.最后,以深圳市为例进行严重交通拥堵评估并提出应对策略,验证了方法的有效性.

  10. Measuring Urban Traffic Congestion – A Review

    Directory of Open Access Journals (Sweden)

    Amudapuram Mohan Rao

    2012-12-01

    Full Text Available Traffic’ congestion has been one of major issues that most metropolises are facing. It is believed that identification of congestion is the first step for selecting appropriate mitigation measures. Congestion - both in perception and in reality - impacts the movement of people. Traffic congestion wastes time, energy and causes pollution. There are broadly two factors, which effect the congestion; (a micro-level factors (b macro-level factors that relate to overall demand for road use. Congestion is ‘triggered’ at the ‘micro’ level (e.g. on the road, and ‘driven’ at the ‘macro’ level. The micro level factors are, for example, many people want to move at the same time, too many vehicles for limited road space. On the other side, macro level factors are e.g. land-use patžterns, car ownership trends, regional economic dynamics, etc. This paper gives an overview and presents the possible ways to identify and measure metrics for urban arterial congestion. A systematic review is carried out, based on measurement metrics such as speed, travel time/delay and volume and level of service. The review covers distinct aspects like definition; measurement criteria followed by different countries/organizations. The strengths and weaknesses of these measures are discussed. Further, a short critique of measurement criteria is presented.

  11. 利用传染病模型研究空中交通拥挤传播规律%Mechanisms of Congestion Propagation in Air Traffic Management Based on Infectious Diseases Model

    Institute of Scientific and Technical Information of China (English)

    代晓旭; 胡明华; 田文; 胡彬

    2015-01-01

    为避免以往研究中主要集中在拥挤传播网络分布和现实数据观察等表象环节,发掘空中交通拥挤传播演变的科学规律,以空中交通拥挤传播与传染病传播过程的相似性分析为切入点,参考传染病SIR模型,建立空中交通拥挤传播模型,并利用相轨线分析和参数分析等方法,得到拥挤传播趋势及阈值,解释了拥挤传播影响因子和消散因子对拥挤传播过程的影响.结合亚特兰大和白云机场实际延误数据,发现所建模型能够恰当地表述基本拥挤过程,但各类因子需根据运行实际调整而无法形成固定值,且对较复杂的拥挤过程需要引入新的参数.%Previous researches mainly focused on the superficial aspects such as the network distribution and real-time data observation of the congestion propagation, on that account, this paper seeks to explore the scientific pattern of the evolution of air traffic congestion propagation. According to the similarity of the process between air traffic congestion propagation and transmission of infectious disease and referring to SIR model of infectious disease, an air traffic congestion propagation model is presented. Phase trajectory analysis and parameter analysis are used to achieve the propagation tendency and threshold value of the congestion. The effects of influence factors and dissipation factors on the propagation process are also explained. Compared with actual delay data from Atlanta and Baiyun airports, it turns up that the model just right fit the basic congestion process. However, all types of factors need to be adjusted according to the practical situation so as to not be able to form fixed values. For more complicated congestion process, new parameters should be involved.

  12. Epidemiology and burden of nasal congestion

    Directory of Open Access Journals (Sweden)

    Michael Stewart

    2010-02-01

    Full Text Available Michael Stewart1, BJ Ferguson2, Len Fromer31Department of Otorhinolaryngology, Weill Cornell Medical College, New York-Presbyterian Hospital/Weill Cornell Medical Center, USA; 2Department of Otolaryngology, University of Pittsburgh School of Medicine, USA; 3University of California, Los Angeles; David Geffen School of Medicine Los Angeles, California, USAAbstract: Nasal congestion, which may be described as fullness, obstruction, reduced airflow, or being “stuffed up,” is a commonly encountered symptom in clinical practice. Systematic study of congestion has largely considered it as a component of a disease state. Conditions associated with congestion include nasal polyposis, obstructive sleep apnea, and anatomic variation; however, most information on the burden of congestion comes from studies of allergic rhinitis and rhinosinusitis, diseases of which congestion is the major symptom. Congestion can be caused by other rhinologic conditions, such as non-allergic rhinitis, viral or bacterial rhinitis, and vasomotor rhinitis. Allergic rhinitis affects as much as one quarter of the population worldwide and imposes a significant economic burden. Additionally, allergic rhinitis significantly impairs quality of life; congestion causes allergic rhinitis sufferers decreased daytime productivity at work or school and reduces night-time sleep time and quality. Annually, rhinosinusitis affects tens of millions of Americans and leads to approximately $6 billion in overall health care expenditures; it has been found to be one of the most costly physical conditions for US employers. Given the high prevalence and significant social and economic burden of nasal congestion, this symptom should be a key consideration in treating patients with rhinologic disease, and there continues to be a significant unmet medical need for effective treatment options for this condition.Keywords: allergic rhinitis, congestion, epidemiology, obstruction, rhinosinusitis

  13. Grid Mapping for Spatial Pattern Analyses of Recurrent Urban Traffic Congestion Based on Taxi GPS Sensing Data

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2017-03-01

    Full Text Available Traffic congestion is one of the most serious problems that impact urban transportation efficiency, especially in big cities. Identifying traffic congestion locations and occurring patterns is a prerequisite for urban transportation managers in order to take proper countermeasures for mitigating traffic congestion. In this study, the historical GPS sensing data of about 12,000 taxi floating cars in Beijing were used for pattern analyses of recurrent traffic congestion based on the grid mapping method. Through the use of ArcGIS software, 2D and 3D maps of the road network congestion were generated for traffic congestion pattern visualization. The study results showed that three types of traffic congestion patterns were identified, namely: point type, stemming from insufficient capacities at the nodes of the road network; line type, caused by high traffic demand or bottleneck issues in the road segments; and region type, resulting from multiple high-demand expressways merging and connecting to each other. The study illustrated that the proposed method would be effective for discovering traffic congestion locations and patterns and helpful for decision makers to take corresponding traffic engineering countermeasures in order to relieve the urban traffic congestion issues.

  14. CoCoA+: an advanced congestion control mechanism for CoAP

    OpenAIRE

    Betzler, August; Gómez Montenegro, Carlos; Seyfettin Demirkol, Ilker; Paradells Aspas, Josep

    2015-01-01

    The Constrained Application Protocol (CoAP) has been designed by the Internet Engineering Task Force (IETF) for Internet of Things (IoT) devices. Due to the limited radio channel capacities and hardware resources of such devices, congestion can be a serious problem. CoAP addresses this important issue with a basic congestion control mechanism. CoCoA, an Internet-Draft proposal, introduced alternative congestion control mechanisms for CoAP. Yet, there has been limited evaluation of these conge...

  15. Comparative Analysis of Congestion Control Algorithms Using ns-2

    CERN Document Server

    Patel, Sanjeev; Garg, Arjun; Mehrotra, Prateek; Chhabra, Manish

    2012-01-01

    In order to curtail the escalating packet loss rates caused by an exponential increase in network traffic, active queue management techniques such as Random Early Detection (RED) have come into picture. Flow Random Early Drop (FRED) keeps state based on instantaneous queue occupancy of a given flow. FRED protects fragile flows by deterministically accepting flows from low bandwidth connections and fixes several shortcomings of RED by computing queue length during both arrival and departure of the packet. Stochastic Fair Queuing (SFQ) ensures fair access to network resources and prevents a busty flow from consuming more than its fair share. In case of (Random Exponential Marking) REM, the key idea is to decouple congestion measure from performance measure (loss, queue length or delay). Stabilized RED (SRED) is another approach of detecting nonresponsive flows. In this paper, we have shown a comparative analysis of throughput, delay and queue length for the various congestion control algorithms RED, SFQ and REM...

  16. Impacts of variable message signs on traffic congestion

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The variable message signs (VMS) have been widely used in guiding and managing the dynamic traffic with development of intelligent transportation technologies. It is known that cell transmission model (CTM) can well reproduce such traffic dynamics as shock waves and jams. This paper presents a new method to estimate the route travel times by using the CTM in conjunction with a logit-based route choice rule. The impacts of VMS on a two-route scenario with recurrent and non-recurrent traffic congestion are numerically investigated by analyzing the changes of route flow and travel time. Simulation results show that in networks with suitable long links, the VMS can positively influence travelers’ decision making so as to improve the system performance. For non-recurrent congestion, the value space of the route choice parameter that affects the flow distribution between two routes is narrower in the case of high traffic demand than that in the low demand case.

  17. Measuring accessibility and congestion in Accra

    DEFF Research Database (Denmark)

    Møller-Jensen, Lasse; Kofie, Richard Y.; Allotey, Albert N.M.

    2012-01-01

    to the city centre. Peak hour traffic speeds are compared with off-peak levels and theoretical free-flow estimations to provide an indica-tion of the level of congestion. It is found that the core areas are somewhat congested during the day period, while the fringe areas are more congested during peak hours...... and less during off-peak hours. Delays are frequently found within the inner fringe areas. The paper discusses the methodological potentials and barriers for applying gps tracklog points for analysing traffic flows within an urban road network....

  18. Stochastic Congestion Control in Wireless Sensor Networks

    Science.gov (United States)

    Kim, Hyung Seok; Lee, Seok; Kim, Namhoon

    In this paper, an effective congestion control algorithm is proposed to increase the end-to-end delivery success ratio of upstream traffic by reduction of buffer drop probabilities and their deviation in wireless sensor networks. According to the queue length of parent and child nodes, each child node chooses one of the parents as the next hop to the sink and controls the delay before transmission begins. It balances traffics among parents and mitigates congestion based on congestion level of a node. Simulation results show that the proposed algorithm reduces buffer drop probabilities and their deviation and increases the end-to-end delivery success ratio in wireless sensor networks.

  19. Congestion-Aware Warehouse Flow Analysis and Optimization

    KAUST Repository

    AlHalawani, Sawsan

    2015-12-18

    Generating realistic configurations of urban models is a vital part of the modeling process, especially if these models are used for evaluation and analysis. In this work, we address the problem of assigning objects to their storage locations inside a warehouse which has a great impact on the quality of operations within a warehouse. Existing storage policies aim to improve the efficiency by minimizing travel time or by classifying the items based on some features. We go beyond existing methods as we analyze warehouse layout network in an attempt to understand the factors that affect traffic within the warehouse. We use simulated annealing based sampling to assign items to their storage locations while reducing traffic congestion and enhancing the speed of order picking processes. The proposed method enables a range of applications including efficient storage assignment, warehouse reliability evaluation and traffic congestion estimation.

  20. 基于大数据下的北京交通拥堵评价指标分析%Index System of Traffic Congestion Evaluation in Beijing Based on Big Data

    Institute of Scientific and Technical Information of China (English)

    王妍颖; 黄宇

    2016-01-01

    交通拥堵评价指标主要用于描述整个路网或者某些特定区域的交通拥堵现象及其潜在规律。现有的研究方法能够从不同侧面反映交通拥堵现象,但不能从整体上多角度反映路网的拥堵状态,也不能够对整个路网实时运行状态进行动态跟踪。本文通过借鉴国外先进的拥堵指标体系,构建了一套符合北京市特点的交通拥堵评价指标体系。基于2011年和2012年北京各个环路检测器的数据,对北京市各个环路的拥堵评价指标进行计算和分析,我们得到了北京市道路网交通拥堵的潜在规律。%The measurement index of traffic congestion is used to describe the phenomena and potential rules of congestion for the entire network or specific areas. The existing methods can measure traffic congestion from several single aspects. However, they cannot demonstrate the full-spectrum congestion condition of the entire network, and also cannot capture the dynamic traffic characteristics. This paper proposes the index system of traffic congestion measurement accord with the character of Beijing by introducing the advanced foreign traffic congestion index. Based on the each loop road detector data in 2011 and 2012, the indices of the traffic congestion measurement of the each Ring-Road in Beijing is calculated and analyzed to obtain the potential regularity of Beijing road network traffic congestion.

  1. Exploring the impact of a coordinated variable speed limit control on congestion distribution in freeway

    Directory of Open Access Journals (Sweden)

    Jing Cao

    2015-06-01

    Full Text Available Over the past few decades, urban freeway congestion has been highly recognized as a serious and worsening traffic problem in the world. To relieve freeway congestion, several active traffic and demand management (ATDM methods have been developed. Among them, variable speed limit (VSL aims at regulating freeway mainline flow upstream to meet existing capacity and to harmonize vehicle speed. However, congestion may still be inevitable even with VSL implemented due to extremely high demand in actual practice. This study modified an existing VSL strategy by adding a new local constraint to suggest an achievable speed limit during the control period. As a queue is a product of the congestion phenomenon in freeway, the incentives of a queue build-up in the applied coordinated VSL control situation were analyzed. Considering a congestion occurrence (a queue build-up characterized by a sudden and sharp speed drop, speed contours were utilized to demonstrate the congestion distribution over a whole freeway network in various scenarios. Finally, congestion distributions found in both VSL control and non-VS control situations for various scenarios were investigated to explore the impact of the applied coordinated VSL control on the congestion distribution. An authentic stretch of Whitemud Drive (WMD, an urban freeway corridor in Edmonton, Alberta, Canada, was employed to implement this modified coordinated VSL control strategy; and a calibrated micro-simulation VISSIM model (model functions was applied as the substitute of the real-world traffic system to test the above mentioned performance. The exploration task in this study can lay the groundwork for future research on how to improve the presented VSL control strategy for achieving the congestion mitigation effect on freeway.

  2. Congested Aggregation via Newtonian Interaction

    Science.gov (United States)

    Craig, Katy; Kim, Inwon; Yao, Yao

    2017-08-01

    We consider a congested aggregation model that describes the evolution of a density through the competing effects of nonlocal Newtonian attraction and a hard height constraint. This provides a counterpoint to existing literature on repulsive-attractive nonlocal interaction models, where the repulsive effects instead arise from an interaction kernel or the addition of diffusion. We formulate our model as the Wasserstein gradient flow of an interaction energy, with a penalization to enforce the constraint on the height of the density. From this perspective, the problem can be seen as a singular limit of the Keller-Segel equation with degenerate diffusion. Two key properties distinguish our problem from previous work on height constrained equations: nonconvexity of the interaction kernel (which places the model outside the scope of classical gradient flow theory) and nonlocal dependence of the velocity field on the density (which causes the problem to lack a comparison principle). To overcome these obstacles, we combine recent results on gradient flows of nonconvex energies with viscosity solution theory. We characterize the dynamics of patch solutions in terms of a Hele-Shaw type free boundary problem and, using this characterization, show that in two dimensions patch solutions converge to a characteristic function of a disk in the long-time limit, with an explicit rate on the decay of the energy. We believe that a key contribution of the present work is our blended approach, combining energy methods with viscosity solution theory.

  3. Computer software management, evaluation, and dissemination

    Science.gov (United States)

    1983-01-01

    The activities of the Computer Software Management and Information Center involving the collection, processing, and distribution of software developed under the auspices of NASA and certain other federal agencies are reported. Program checkout and evaluation, inventory control, customer services and marketing, dissemination, program maintenance, and special development tasks are discussed.

  4. Outcomes Oriented Planning, Management, and Evaluation.

    Science.gov (United States)

    Kinnison, Charles J.

    An outcomes orientation is examined as the dominant focus for formulating improvements in a college's planning, management, and evaluation (PME) system. Outcomes are seen as individual (produced by college personnel or students), program related, or institutional. An outcomes orientation to PME has the advantages of relating to the quality of…

  5. The Construction of the Performance Management Teaching Portfolio Evaluation System

    Institute of Scientific and Technical Information of China (English)

    范华

    2016-01-01

    Two of the evaluation, Teaching Portfolio and Performance Management, have being introduced in this article, in order to lead to the construction of the Performance Management Teaching Portfolio Evaluation System.The Performance Manage-ment Teaching Portfolio Evaluation System has advantages of both Teaching Portfolio and Performance Management. The arti-cle also also has listed the elements and some examples of the Performance Management Teaching Portfolio Evaluation System.

  6. Emission Patterns under Alternative Congestion and Motor Vehicle Pollution Mitigation Policies in Shanghai

    Institute of Scientific and Technical Information of China (English)

    Chen Hongfeng; Li Fen; Li Xiangling

    2007-01-01

    As a megacity with thriving economy, Shanghai is experiencing rapid motorisation and confronted with traffic congestion problems despite its low car ownership. It is of value to look into the policies on emission control of motor vehicle and congestion reduction in such a city to explore how to reconcile mobility enhancement with the environment. Results of a dynamic simulation displayed time paths of emissions from motor vehicles in Shanghai over the period from 2000 to 2020. The simulation results showed that early policies on emission control of motor vehicle could bring about far-reaching effects on emission reduction, and take advantage of available low-polluting technologies and technical innovation over time. Travel demand management would play an important role in curbing congestion and reducing motor vehicle pollution by calming down car ownership rise and deterring inefficient trips as well as reducing fuel waste caused by congestion.

  7. Traffic Congestion Mechanism in Two Ramp Systems

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiao-Mei; SONG Gui-Cui; SONG Yu-Kun

    2011-01-01

    The aim of this paper is to study traffic properties in an on/off-ramp system with a bus stop close to the on/off ramp.The location of the bus stop in the on/off-ramp (thereafter downstream or upstream case) is discussed.The simulation results show that in the two ramp systems, the reasons for traffic congestions are different.In the on-ramp system, buses and cars coming from on-ramp interweave each other, while in the off-ramp system, buses interweave with cars exiting to off-ramp.Thus, in the on-ramp (off-ramp) system, the upstream (downstream) bus stop is helpful to reduce the interweaving situation.Moreover, the negative effect will disappear when the distance between the bus stop and the on/off-ramp is more than 20 cells (i.e.150 m).These qualitative findings may provide some suggestions on traffic management and optimization.

  8. Pre-Congestion Notification (PCN) Architecture

    NARCIS (Netherlands)

    Eardley, P; Chan, K.; Charny, A.; Geib, R.; Karagiannis, Georgios; Menth, M.; Tsou, T.; Eardley, P

    2009-01-01

    This document describes a general architecture for flow admission and termination based on pre-congestion information in order to protect the quality of service of established, inelastic flows within a single Diffserv domain.

  9. Traffic congestion in interconnected complex networks.

    Science.gov (United States)

    Tan, Fei; Wu, Jiajing; Xia, Yongxiang; Tse, Chi K

    2014-06-01

    Traffic congestion in isolated complex networks has been investigated extensively over the last decade. Coupled network models have recently been developed to facilitate further understanding of real complex systems. Analysis of traffic congestion in coupled complex networks, however, is still relatively unexplored. In this paper, we try to explore the effect of interconnections on traffic congestion in interconnected Barabási-Albert scale-free networks. We find that assortative coupling can alleviate traffic congestion more readily than disassortative and random coupling when the node processing capacity is allocated based on node usage probability. Furthermore, the optimal coupling probability can be found for assortative coupling. However, three types of coupling preferences achieve similar traffic performance if all nodes share the same processing capacity. We analyze interconnected Internet autonomous-system-level graphs of South Korea and Japan and obtain similar results. Some practical suggestions are presented to optimize such real-world interconnected networks accordingly.

  10. Congestion and cascades in payment systems

    Science.gov (United States)

    Beyeler, Walter E.; Glass, Robert J.; Bech, Morten L.; Soramäki, Kimmo

    2007-10-01

    We develop a parsimonious model of the interbank payment system. The model incorporates an endogenous instruction arrival process, a scale-free topology of payments between banks, a fixed total liquidity which limits banks’ capacity to process arriving instructions, and a global market that distributes liquidity. We find that at low liquidity the system becomes congested and payment settlement loses correlation with payment instruction arrival, becoming coupled across the network. The onset of congestion is evidently related to the relative values of three characteristic times: the time for banks’ net position to return to 0, the time for a bank to exhaust its liquidity endowment, and the liquidity market relaxation time. In the congested regime settlement takes place in cascades having a characteristic length scale. A global liquidity market substantially attenuates congestion, requiring only a small fraction of the payment-induced liquidity flow to achieve strong beneficial effects.

  11. Traffic congestion in interconnected complex networks

    CERN Document Server

    Tan, Fei; Xia, Yongxiang; Tse, Chi K

    2014-01-01

    Traffic congestion in isolated complex networks has been investigated extensively over the last decade. Coupled network models have recently been developed to facilitate further understanding of real complex systems. Analysis of traffic congestion in coupled complex networks, however, is yet to come. In this paper, we try to explore the effect of interconnections on traffic congestion in interconnected BA scale-free networks. We find that assortative coupling can alleviate traffic congestion better than disassortative and random coupling when the node processing capacity is allocated based on node usage probability. Furthermore, the optimal coupling probability can be found for assortative coupling. However, three types of coupling preferences achieve similar traffic performance if all nodes share the same processing capacity. We analyze interconnected Internet AS-level graphs of Japan and South Korea and obtain similar results. Some practical suggestions are presented to optimize such real-world interconnect...

  12. Understanding congested travel in urban areas

    Science.gov (United States)

    Çolak, Serdar; Lima, Antonio; González, Marta C.

    2016-03-01

    Rapid urbanization and increasing demand for transportation burdens urban road infrastructures. The interplay of number of vehicles and available road capacity on their routes determines the level of congestion. Although approaches to modify demand and capacity exist, the possible limits of congestion alleviation by only modifying route choices have not been systematically studied. Here we couple the road networks of five diverse cities with the travel demand profiles in the morning peak hour obtained from billions of mobile phone traces to comprehensively analyse urban traffic. We present that a dimensionless ratio of the road supply to the travel demand explains the percentage of time lost in congestion. Finally, we examine congestion relief under a centralized routing scheme with varying levels of awareness of social good and quantify the benefits to show that moderate levels are enough to achieve significant collective travel time savings.

  13. Time, speeds, flows and densities in static models of road traffic congestion and congestion pricing

    OpenAIRE

    Verhoef, E.T.

    1998-01-01

    This paper studies some of the properties and fundamentals of static models of road traffic congestion that have triggered much debate in the literature. The first part of the paper focuses in particular on the difficulties arising with the backward-bending cost curve in the context of 'continuous congestion'. Therelevance of the backward-bending segment of the cost curve for the static analysis of congestion is questioned by demonstrating that 'equilibria' on this segment produce upwards shi...

  14. Congestion Avoidance for Multiple Micro-robots Using the Behaviour of Fish Schools

    Directory of Open Access Journals (Sweden)

    Yaniss Touahmi

    2012-09-01

    Full Text Available This article summarizes a research topic which discusses one of the most common problems in multiple micro‐robots’ navigation, namely congestion avoidance. This situation occurs when troops of micro‐robots moving in different directions meet each other at a common area causing congestion situations. To avoid this risky state ‐ which can create an inextricable scenario ‐ firstly, we established a local and a global communication network that manages the robots’ displacement through formation control. This warns each of them of the existence of a risk of congestion and manages the choice of the priority group, which is a new concept that we introduce in order to deal with this kind of congestion conflict. Secondly, we consider a new algorithm based on chaotic equations and inspired by the behaviour of schools of fish, which solves the congestion problem by creating a bifurcation of the troop’s configuration and enables the proper avoidance of the conflict exhibited by congestion.

  15. Evaluation and Management of Breast Calcifications

    Directory of Open Access Journals (Sweden)

    Behrooz Zandi

    2010-05-01

    Full Text Available When evaluating mammograms, one looks for masses, areas of asymmetry or architectural distortion and microcalcifications."nCalcification found on screening and diagnostic mammography may be typically benign, of intermediate type, or have a high probability of malignancy."nThe calcifications that most radiologists have prob-lems dealing with are those of "intermediate con-cern.""nOccasionally spot compression-magnification views are necessary to evaluate and analyze the calcification characteristics."nThe morphology and distribution of calcifications are often clues to the differential diagnosis and appropriate management. Calcifications deserve closer scrutiny than those in a regional or diffuse distribution."nIn this article, we discuss the imaging evaluation and management of lesions found on screening and diagnostic mammography, with the focus on commonly encumbered questions and problems. We will also present our interesting cases with breast calcification.

  16. Focus on renal congestion in heart failure

    OpenAIRE

    Afsar, Baris; Ortiz, Alberto; Covic, Adrian; Solak, Yalcin; Goldsmith, David; Kanbay, Mehmet

    2015-01-01

    Hospitalizations due to heart failure are increasing steadily despite advances in medicine. Patients hospitalized for worsening heart failure have high mortality in hospital and within the months following discharge. Kidney dysfunction is associated with adverse outcomes in heart failure patients. Recent evidence suggests that both deterioration in kidney function and renal congestion are important prognostic factors in heart failure. Kidney congestion in heart failure results from low cardia...

  17. Velo-pharyngeal dysfunction: Evaluation and management

    Directory of Open Access Journals (Sweden)

    Marsh Jeffrey

    2009-10-01

    Full Text Available Separation of the nasal and oral cavities by dynamic closure of the velo-pharyngeal port is necessary for normal speech and swallowing. Velo-pharyngeal dysfunction (VPD may either follow repair of a cleft palate or be independent of clefting. While the diagnosis of VPD is made by audiologic perceptual evaluation of speech, identification of the mechanism of the dysfunction requires instrumental visualization of the velo-pharyngeal port during specific speech tasks. Matching the specific intervention for management of VPD with the type of dysfunction, i.e. differential management for differential diagnosis, maximizes the result while minimizing the morbidity of the intervention.

  18. Congestive heart failure in acromegaly: A review of 6 cases

    Directory of Open Access Journals (Sweden)

    P Dutta

    2012-01-01

    Full Text Available Background: Though cardiac involvement is common in acromegaly, overt congestive heart failure is uncommon. Materials and Methods: This is retrospective analysis of hospital record between 1996 and 2007. We analyzed records of 150 consecutive patients with acromegaly. We included the patients with acromegaly those who had overt congestive heart failure either at presentation or during the course of illness for the present analysis. The diagnosis of acromegaly and congestive cardiac failure were based on standard criteria. Results:Out of 150 patients with acromegaly, 6 patients had overt CHF (4.0%, of which 4 presented with the features of CHF and 2 developed during the course of illness. Three patients had hypertension and 1 had diabetes. Baseline echocardiography showed severe biventricular dysfunction and global hypokinesia in all. Angiography showed dilated hypokinetic left ventricle with normal coronaries in 3, it was confirmed at autopsy in 1. Three underwent trans-sphenoidal surgery, 1 received somatostatin analogue as primary treatment modality. Normalization of growth hormone and IGF-1 led to improvement in cardiac function in 1, 1 patient lost to follow up, and 4 died during the course of illness. In 1 patient, autopsy was performed and cardiac specimen revealed normal coronaries, concentric ventricular hypertrophy, and dilatation with myofibrolysis and interfascicular fibrosis. Conclusion:Prevalence of overt CHF is 4% in present series. Overt CHF carries poor prognosis and hence, this complication should be recognized at earliest, and medical management to normalized cardiac function should be given utmost priority.

  19. Traffic Congestion Detection System through Connected Vehicles and Big Data

    Directory of Open Access Journals (Sweden)

    Néstor Cárdenas-Benítez

    2016-04-01

    Full Text Available This article discusses the simulation and evaluation of a traffic congestion detection system which combines inter-vehicular communications, fixed roadside infrastructure and infrastructure-to-infrastructure connectivity and big data. The system discussed in this article permits drivers to identify traffic congestion and change their routes accordingly, thus reducing the total emissions of CO2 and decreasing travel time. This system monitors, processes and stores large amounts of data, which can detect traffic congestion in a precise way by means of a series of algorithms that reduces localized vehicular emission by rerouting vehicles. To simulate and evaluate the proposed system, a big data cluster was developed based on Cassandra, which was used in tandem with the OMNeT++ discreet event network simulator, coupled with the SUMO (Simulation of Urban MObility traffic simulator and the Veins vehicular network framework. The results validate the efficiency of the traffic detection system and its positive impact in detecting, reporting and rerouting traffic when traffic events occur.

  20. Traffic Congestion Detection System through Connected Vehicles and Big Data

    Science.gov (United States)

    Cárdenas-Benítez, Néstor; Aquino-Santos, Raúl; Magaña-Espinoza, Pedro; Aguilar-Velazco, José; Edwards-Block, Arthur; Medina Cass, Aldo

    2016-01-01

    This article discusses the simulation and evaluation of a traffic congestion detection system which combines inter-vehicular communications, fixed roadside infrastructure and infrastructure-to-infrastructure connectivity and big data. The system discussed in this article permits drivers to identify traffic congestion and change their routes accordingly, thus reducing the total emissions of CO2 and decreasing travel time. This system monitors, processes and stores large amounts of data, which can detect traffic congestion in a precise way by means of a series of algorithms that reduces localized vehicular emission by rerouting vehicles. To simulate and evaluate the proposed system, a big data cluster was developed based on Cassandra, which was used in tandem with the OMNeT++ discreet event network simulator, coupled with the SUMO (Simulation of Urban MObility) traffic simulator and the Veins vehicular network framework. The results validate the efficiency of the traffic detection system and its positive impact in detecting, reporting and rerouting traffic when traffic events occur. PMID:27136548

  1. Credit Institutions Management Evaluation using Quantitative Methods

    Directory of Open Access Journals (Sweden)

    Nicolae Dardac

    2006-02-01

    Full Text Available Credit institutions supervising mission by state authorities is mostly assimilated with systemic risk prevention. In present, the mission is orientated on analyzing the risk profile of the credit institutions, the mechanism and existing systems as management tools providing to bank rules the proper instruments to avoid and control specific bank risks. Rating systems are sophisticated measurement instruments which are capable to assure the above objectives, such as success in banking risk management. The management quality is one of the most important elements from the set of variables used in the quoting process in credit operations. Evaluation of this quality is – generally speaking – fundamented on quantitative appreciations which can induce subjectivism and heterogeneity in quotation. The problem can be solved by using, complementary, quantitative technics such us DEA (Data Envelopment Analysis.

  2. Evaluation Framework for Quality Management Software

    Directory of Open Access Journals (Sweden)

    Nadica Hrgarek

    2008-06-01

    Full Text Available Identifying and specifying user requirements is an integral part of information systems design and is critical for the project success. More than 50% of the reasons for the project failure presented in the CHAOS report [36] and study of a US Air Force project by Sheldon et al. [33] are related to requirements. The goal of this paper is to assess the relevant user and software requirements which are the basis for an electronic quality management system selection in medical device companies. This paper describes the structured evaluation and selection process of different quality management software tools that shall support business processes. The purpose of this paper is to help the small to medium size medical device companies to choose the right quality management software which meets the company's business needs.

  3. Managing the Taiwan kindergarten evaluation system

    Directory of Open Access Journals (Sweden)

    Lin, Hsiu Fen

    2012-04-01

    Full Text Available The purpose of this study is to explore the content of Taiwan’s kindergarten accreditation system and its current status, and set forth conclusions and recommendations for future references by policy-making authorities in kindergarten education. Using the documentary analysis method, results show that current evaluation system should practice more transparency in its administration. Furthermore, managers of such system should be encouraged to consider other countries’ kindergarten accreditation systems for references.

  4. Apoptosis and congestive heart failure.

    Science.gov (United States)

    Feuerstein, G; Ruffolo, R R; Yue, T L

    1997-10-01

    Congestive heart failure (CHF) is the final clinical manifestation of a variety of cardiac (myopathies), coronary (atherosclerosis), and systemic diseases (diabetes, hypertension). Regardless of the origin of the cardiac insult, left ventricular dysfunction resulting in decreased cardiac output elicits a series of adaptational processes that attempt to compensate for some of the decrement in myocardial function. One of the key manifestations of these compensatory processes is cardiac hypertrophy, which is characterized by a marked increase in myocyte size and an increase in contractile proteins. The benefits resulting from these compensatory adaptational mechanisms, however, are only transient, and within a period of months to years, the changes induced in the myocardium fail to sustain cardiac output at a level that is sufficient to meet the demands of the body; subsequently, physical performance is impaired. Typically, progressive dilation and thinning of the left ventricle occur along with progression of CHF. The mechanisms responsible for the thinning of ventricular tissue and loss of left ventricular mass are poorly understood; traditionally, such loss has been attributed to tissue necrosis based on the morphologic observation of dead cardiac myocytes. Very recently, there have been data suggesting that apoptosis, a form of programmed cell death (PCD), occurs in the heart and may be responsible, at least in part, for the progression of CHF and the chronic loss of left ventricular function and mass. Evidence for a role of apoptosis/PCD in the progression of heart failure has been obtained from a variety of observations, including in vitro studies of cardiac myocytes in culture, experimental animal models of cardiac injury, and cardiac tissue obtained from patients with CHF. Thus, apoptosis/PCD may be a critical mechanism involved in the progressive loss of cardiac myocytes, which ultimately results in end-stage heart failure. In this brief review, the evidence

  5. Evaluator and Program Manager Perceptions of Evaluation Capacity and Evaluation Practice

    Science.gov (United States)

    Fierro, Leslie A.; Christie, Christina A.

    2017-01-01

    The evaluation community has demonstrated an increased emphasis and interest in evaluation capacity building in recent years. A need currently exists to better understand how to measure evaluation capacity and its potential outcomes. In this study, we distributed an online questionnaire to managers and evaluation points of contact working in…

  6. Congestion transition in air traffic networks.

    Science.gov (United States)

    Monechi, Bernardo; Servedio, Vito D P; Loreto, Vittorio

    2015-01-01

    Air Transportation represents a very interesting example of a complex techno-social system whose importance has considerably grown in time and whose management requires a careful understanding of the subtle interplay between technological infrastructure and human behavior. Despite the competition with other transportation systems, a growth of air traffic is still foreseen in Europe for the next years. The increase of traffic load could bring the current Air Traffic Network above its capacity limits so that safety standards and performances might not be guaranteed anymore. Lacking the possibility of a direct investigation of this scenario, we resort to computer simulations in order to quantify the disruptive potential of an increase in traffic load. To this end we model the Air Transportation system as a complex dynamical network of flights controlled by humans who have to solve potentially dangerous conflicts by redirecting aircraft trajectories. The model is driven and validated through historical data of flight schedules in a European national airspace. While correctly reproducing actual statistics of the Air Transportation system, e.g., the distribution of delays, the model allows for theoretical predictions. Upon an increase of the traffic load injected in the system, the model predicts a transition from a phase in which all conflicts can be successfully resolved, to a phase in which many conflicts cannot be resolved anymore. We highlight how the current flight density of the Air Transportation system is well below the transition, provided that controllers make use of a special re-routing procedure. While the congestion transition displays a universal scaling behavior, its threshold depends on the conflict solving strategy adopted. Finally, the generality of the modeling scheme introduced makes it a flexible general tool to simulate and control Air Transportation systems in realistic and synthetic scenarios.

  7. Using relaxational dynamics to reduce network congestion

    Science.gov (United States)

    Piontti, Ana L. Pastore y.; La Rocca, Cristian E.; Toroczkai, Zoltán; Braunstein, Lidia A.; Macri, Pablo A.; López, Eduardo

    2008-09-01

    We study the effects of relaxational dynamics on congestion pressure in scale-free (SF) networks by analyzing the properties of the corresponding gradient networks (Toroczkai and Bassler 2004 Nature 428 716). Using the Family model (Family and Bassler 1986 J. Phys. A: Math. Gen. 19 L441) from surface-growth physics as single-step load-balancing dynamics, we show that the congestion pressure considerably drops on SF networks when compared with the same dynamics on random graphs. This is due to a structural transition of the corresponding gradient network clusters, which self-organize so as to reduce the congestion pressure. This reduction is enhanced when lowering the value of the connectivity exponent λ towards 2.

  8. 41 CFR 60-2.30 - Corporate management compliance evaluations.

    Science.gov (United States)

    2010-07-01

    ... Relating to Public Contracts OFFICE OF FEDERAL CONTRACT COMPLIANCE PROGRAMS, EQUAL EMPLOYMENT OPPORTUNITY, DEPARTMENT OF LABOR 2-AFFIRMATIVE ACTION PROGRAMS Miscellaneous § 60-2.30 Corporate management compliance evaluations. (a) Purpose. Corporate Management Compliance Evaluations are designed to ascertain...

  9. Adaptive mechanism-based congestion control for networked systems

    Science.gov (United States)

    Liu, Zhi; Zhang, Yun; Chen, C. L. Philip

    2013-03-01

    In order to assure the communication quality in network systems with heavy traffic and limited bandwidth, a new ATRED (adaptive thresholds random early detection) congestion control algorithm is proposed for the congestion avoidance and resource management of network systems. Different to the traditional AQM (active queue management) algorithms, the control parameters of ATRED are not configured statically, but dynamically adjusted by the adaptive mechanism. By integrating with the adaptive strategy, ATRED alleviates the tuning difficulty of RED (random early detection) and shows a better control on the queue management, and achieve a more robust performance than RED under varying network conditions. Furthermore, a dynamic transmission control protocol-AQM control system using ATRED controller is introduced for the systematic analysis. It is proved that the stability of the network system can be guaranteed when the adaptive mechanism is finely designed. Simulation studies show the proposed ATRED algorithm achieves a good performance in varying network environments, which is superior to the RED and Gentle-RED algorithm, and providing more reliable service under varying network conditions.

  10. How Travel Demand Affects Detection of Non-Recurrent Traffic Congestion on Urban Road Networks

    Science.gov (United States)

    Anbaroglu, B.; Heydecker, B.; Cheng, T.

    2016-06-01

    Occurrence of non-recurrent traffic congestion hinders the economic activity of a city, as travellers could miss appointments or be late for work or important meetings. Similarly, for shippers, unexpected delays may disrupt just-in-time delivery and manufacturing processes, which could lose them payment. Consequently, research on non-recurrent congestion detection on urban road networks has recently gained attention. By analysing large amounts of traffic data collected on a daily basis, traffic operation centres can improve their methods to detect non-recurrent congestion rapidly and then revise their existing plans to mitigate its effects. Space-time clusters of high link journey time estimates correspond to non-recurrent congestion events. Existing research, however, has not considered the effect of travel demand on the effectiveness of non-recurrent congestion detection methods. Therefore, this paper investigates how travel demand affects detection of non-recurrent traffic congestion detection on urban road networks. Travel demand has been classified into three categories as low, normal and high. The experiments are carried out on London's urban road network, and the results demonstrate the necessity to adjust the relative importance of the component evaluation criteria depending on the travel demand level.

  11. HOW TRAVEL DEMAND AFFECTS DETECTION OF NON-RECURRENT TRAFFIC CONGESTION ON URBAN ROAD NETWORKS

    Directory of Open Access Journals (Sweden)

    B. Anbaroglu

    2016-06-01

    Full Text Available Occurrence of non-recurrent traffic congestion hinders the economic activity of a city, as travellers could miss appointments or be late for work or important meetings. Similarly, for shippers, unexpected delays may disrupt just-in-time delivery and manufacturing processes, which could lose them payment. Consequently, research on non-recurrent congestion detection on urban road networks has recently gained attention. By analysing large amounts of traffic data collected on a daily basis, traffic operation centres can improve their methods to detect non-recurrent congestion rapidly and then revise their existing plans to mitigate its effects. Space-time clusters of high link journey time estimates correspond to non-recurrent congestion events. Existing research, however, has not considered the effect of travel demand on the effectiveness of non-recurrent congestion detection methods. Therefore, this paper investigates how travel demand affects detection of non-recurrent traffic congestion detection on urban road networks. Travel demand has been classified into three categories as low, normal and high. The experiments are carried out on London’s urban road network, and the results demonstrate the necessity to adjust the relative importance of the component evaluation criteria depending on the travel demand level.

  12. Development and evaluation of project management effectiveness

    Directory of Open Access Journals (Sweden)

    L.L. Kalinichenko

    2016-12-01

    Full Text Available The aim of the article. The author notes that by Studying the work of project management, we can say that researchers distinguish effectiveness from the standpoint of professional activities at the project and organizational and psychological climate activities. The results of the analysis. Professionally efficiency is, first and foremost, the focus of the entire team at the end result, initiative and creative approach to solving problems. From the standpoint of organizational and psychological climate effective is such a command, in which: informal atmosphere; the objective is clear and accepted; the members listen to each other; discuss the issues, involving all members; conflicts and disagreements are present but are expressed and centered around ideas and methods, not personalities; the group is aware that does, decisions are based on consensus, not on majority vote. Under these conditions, the team not only successfully fulfills its mission, but also meets the personal and interpersonal needs of their members, resulting in the output result, which has implemented project with the planned performance as a measure of team activity. Effective management of the project team depends largely on the efficiency of project management, innovation and effective use of investment. The following article in the graphic scheme of forming an effective project team gives an idea of what the process is gradual and multidimensional, requires the project manager skills to rally the team, allocate responsibilities, set goals and monitor the activities of each member of the team. Conclusions and directions of further researches. In general, the novelty of this article is that the author describes a technique that enables to assess the effectiveness of the management team working on the project, taking into account the time that is, the leaders for team building, cohesion of its members, raising the level of competence of experts. This technique is simple in

  13. An intriguing association between congestive heart failure and An intriguing association between congestive heart failure and diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    SHEN Wei-feng

    2010-01-01

    @@ The prevalence of type 2 diabetes is rising at an alarming rate in China due to aging of the population,increased frequency of obesity, and suboptimal nutritional habits.~1 Although many diabetic Patients now survive severe coronary lesions or myocardial infarction as a result of dramatic advances in the management of ischemic heart disease in general and acute myocardial infarction specifically,~(2,3) they are subsequently succumbing to the consequences of myocardial damage, with an increased incidence of congestive heart failure (CHF).~4

  14. Using predictive modeling to evaluate the financial effect of disease management.

    Science.gov (United States)

    Whitlock, Terry; Johnston, Kenton

    2006-09-01

    The objective of this study was to use predictive modeling to evaluate a disease management (DM) program's effect on a chronically ill population. Specifically, diagnostic cost grouping (DCG) predictive modeling was utilized to measure the financial effect of DM in populations of individuals with congestive heart failure and coronary artery disease. The literature of current practices regarding DM's financial effect measurement was reviewed and critiqued--especially with reference to the population-based pre-post method. The time period for the present study is three years, and the variables of interest are financial metrics. Claims data and DM program-specific data covering the 24-month period of 2001 to 2002 and the 24-month period of 2002 to 2003 were analyzed. The mean differences between DCG predicted and actual total claims costs in 2002 and in 2003 were computed. Inflation factors, based on actual health plan population experience for the populations in question, were developed and applied to accurately evaluate financial effect. The preliminary findings suggest that a study design utilizing DCG predictive modeling in evaluating DM program financial impact provides more accurate results compared with the population-based pre-post method currently favored by DM companies.

  15. On the Efficiency of the New York Independent System OperatorMarket for Transmission Congestion Contracts

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, Afzal S.; Bartholomew, Emily S.; Marnay, Chris; Oren,Shmuel S.

    2003-04-01

    The physical nature of electricity generation and deliverycreates special problems for the design of efficient markets, notably theneed to manage delivery in real time and the volatile congestion andassociated costs that result. Proposals for the operation of thederegulated electricity industry tend towards one of two paradigms:centralized and decentralized. Transmission congestion management can beimplemented in the more centralized point-to-point approach, a in NewYork state, where derivative transmission congestion contracts (TCCs) aretraded, or in the more decentralized flowgate-based approach. While it iswidely accepted that theoretically TCCs have attractive properties ashedging instruments against congestion cost uncertainty, whetherefficient markets for them can be established in practice has beenquestioned. Based on an empirical analysis of publicly available datafrom years 2000 and 2001, it appears that New York TCCs providedmarketparticipants with a potentially effective hedge against volatilecongestion rents. However, the prices paid for TCCs systematicallydiverged from the resulting congestion rents for distant locations and athigh prices. The price paid for the hedge not being in line with thecongestion rents, i.e. unreasonably high risk premiums are being paid,suggests an inefficient market. The low liquidity of TCC markets and thedeviation of TCC feasibility requirements from actual energy flows arepossible explanations.

  16. Corporate solutions to caseload management -- an evaluation.

    Science.gov (United States)

    Hoskins, Robert; Gow, Ann; McDowell, Joan

    2007-09-01

    This paper describes an evaluation of a change in health visiting service delivery from GP caseload management to corporate caseload working, in one inner city health centre located in a deprived area of Glasgow. The aim of the study was to identify if moving to corporate caseload working provides the reported benefits cited in the limited literature available. A purposive sample consisting of ten health visitors, one GP, one manager and three clients volunteered to participate in this mixed methods evaluation study. Data were collected by means of a stress questionnaire, public health nursing diary, focus groups and semi-structured interviews. Findings show that immediate improvements were seen in team working, staff communication, sharing practice, enhanced clinical reflection and standards of documentation. However, corporate caseload working did not appear to reduce staff stress levels, increase public health nursing activity or improve quality of client service. Further research conducted over a longer time period with a full staffing complement is needed to validate these findings.

  17. Update in cardiomyopathies and congestive heart failure

    Directory of Open Access Journals (Sweden)

    The Heart Hospital, London, UK and Monaldi Hospital, Naples, Italy

    2012-05-01

    Full Text Available This abstract book contains four reports and all abstracts presented to the Joint Meeting: Update in cardiomyopathies and congestive heart failure, 22-23 September 2011 - Naples, Italy, endorsed by the Working Group on Myocardial and Pericardial Diseases (WG 21 of the European Society of Cardiology (ESC.

  18. Public Congestion Network Situations, and Related Games

    NARCIS (Netherlands)

    Kleppe, J.; Reijnierse, J.H.

    2007-01-01

    This paper analyzes congestion effects on network situations from a cooperative game theoretic perspective. In network situations players have to connect themselves to a source. Since we consider publicly available networks any group of players is allowed to use the entire network to establish their

  19. Urban traffic congestion propagation and bottleneck identification

    Institute of Scientific and Technical Information of China (English)

    LONG JianCheng; GAO ZiYou; REN HuaLing; LIAN AiPing

    2008-01-01

    Bottlenecks in urban traffic network are sticking points in restricting network col-lectivity traffic efficiency.To identify network bottlenecks effectively is a founda-tional work for improving network traffic condition and preventing traffic conges-tion.In this paper,a congestion propagation model of urban network traffic is proposed based on the cell transmission model (CTM).The proposed model in-cludes a link model,which describes flow propagation on links,and a node model,which represents link-to-link flow propagation.A new method of estimating average journey velocity (AJV) of both link and network is developed to identify network congestion bottlenecks.A numerical example is studied in Sioux Falls urban traffic network.The proposed model is employed in simulating network traffic propaga-tion and congestion bottleneck identification under different traffic demands.The simulation results show that continual increase of traffic demand is an immediate factor in network congestion bottleneck emergence and increase as well as re-ducing network collectivity capability.Whether a particular link will become a bot-tleneck is mainly determined by its position in network,its traffic flow (attributed to different OD pairs) component,and network traffic demand.

  20. General Geographical Economics Model with Congestion

    NARCIS (Netherlands)

    J.G.M. van Marrewijk (Charles)

    2005-01-01

    textabstractWe derive and discuss a general, but simple geographical economics model with congestion, allowing us to explain the economic viability of small and large locations. The model generalizes some previous work and lends itself to analyzing the impact of public policy in terms of

  1. EFFICIENCY INCREASE OF CONGESTION FLOWS DETERMINATION

    Directory of Open Access Journals (Sweden)

    O. Denysenko

    2009-01-01

    Full Text Available A short review of congestion flows determination methods (CF is presented. The models for time intervals determination of vehicles flow at the stop-line and the magnitude of the ideal CF are presented. The estimation of modeling results according to experimental data is carried out.

  2. Overview of Pre-Congestion Notification Encoding

    NARCIS (Netherlands)

    Karagiannis, G.; Chan, K.; Moncaster, T.; Menth, M.; Eardley, P.; Briscoe, B.

    2012-01-01

    The objective of Pre-Congestion Notification (PCN) is to protect the quality of service (QoS) of inelastic flows within a Diffserv domain. On every link in the PCN-domain, the overall rate of PCN-traffic is metered, and PCN-packets are appropriately marked when certain configured rates are exceeded.

  3. News from the Internet congestion control world

    CERN Document Server

    Rossi, Dario; Valenti, Silvio; Veglia, Paolo; Muscariello, Luca

    2009-01-01

    A few months ago, the BitTorrent developers announced that the transfer of torrent data in the official client was about to switch to uTP, an application-layer congestion-control protocol using UDP at the transport-layer. This announcement immediately raised an unmotivated buzz about a new, imminent congestion collapse of the whole Internet. Though this reaction was not built on solid technical foundation, nevertheless a legitimate question remains: i.e., whether this novel algorithm is a necessary building block for future Internet applications, or whether it may result in an umpteenth addition to the already well populated world of Internet congestion control algorithms. In this paper, we tackle precisely this issue. The novel protocol is now under discussion at the IETF LEDBAT working group, and has been defined in a draft document in March 2009, whose adoption decision will be taken at the beginning of August 2009. Adhering to the IETF draft definition, we implement the LEDBAT congestion control algorithm...

  4. Peer effects and local congestion in networks

    NARCIS (Netherlands)

    Currarini, Sergio; Fumagalli, E.; Panebianco, Fabrizio

    We study linear quadratic games played on a network. Agents face peer effects with distance-one neighbors, and strategic substitution with distance-two neighbors (local congestion). For this class of games, we show that an interior equilibrium exists both in the high and in the low regions of the

  5. Burstiness-Aware Congestion Control Protocol for Wireless Sensor Networks

    Institute of Scientific and Technical Information of China (English)

    Liang Lulu; Gao Deyun; Qin Yajuan; Zhang Hongke

    2011-01-01

    In monitoring Wireless Sensor Networks (WSNs),the traffic usually has bursty characteristics when an event occurs.Transient congestion would increase delay and packet loss rate severely,which greatly reduces network performance.To solve this problem,we propose a Burstiness-aware Congestion.Control Protocol (BCCP) for wireless sensor networks.In BCCP,the backoff delay is adopted as a congestion indication.Normally,sensor nodes work on contention-based MAC protocol (such as CSMA/CA).However,when congestion occurs,localized TDMA instead of CSMA/CA is embedded into the nodes around the congestion area.Thus,the congestion nodes only deliver their data during their assigned slots to alleviate the contention-caused congestion.Finally,we implement BCCP in our sensor network testbed.The experiment results show that BCCP could detect area congestion in time,and improve the network performance significantly in terms of delay and packet loss rate.

  6. Prolonged signal-averaged P wave duration as a prognostic marker for morbidity and mortality in patients with congestive heart failure

    DEFF Research Database (Denmark)

    Dixen, Ulrik; Wallevik, Laura; Hansen, Maja;

    2003-01-01

    To evaluate the prognostic roles of prolonged signal-averaged P wave duration (SAPWD), raised levels of natriuretic peptides, and clinical characteristics in patients with stable congestive heart failure (CHF).......To evaluate the prognostic roles of prolonged signal-averaged P wave duration (SAPWD), raised levels of natriuretic peptides, and clinical characteristics in patients with stable congestive heart failure (CHF)....

  7. Congestive Heart Failure: A Case of Protein Misfolding

    Science.gov (United States)

    Ha, Chung-Eun; Bhagavan, Nadhipuram V; Loscalzo, Miki; Chan, Stephen K; Nguyen, Huy V; Rios, Carlos N

    2014-01-01

    This article describes an interesting case of a patient presenting with congestive heart failure found to have restrictive cardiomyopathy with initial laboratory evaluation showing hypogammaglobuminemia without a monoclonal band on serum and urine electrophoresis. This case highlights the clinically significant cardiac manifestation caused by protein misfolding, a defect in protein homeostasis. In addition, the utility of a relatively newer laboratory test, serum free light chains as well as the importance of clinical and pathophysiologic correlation is also discussed. We present a relatively uncommon cause of heart disease, cardiac amyloidosis in a patient with a systemic plasma cell dyscrasia, and multiple myeloma. PMID:24959390

  8. 考虑电力系统阻塞的电网充裕度评价%Power Network Adeouacv Assessment Considering Transmission Congestion

    Institute of Scientific and Technical Information of China (English)

    韩如月; 万秋兰

    2011-01-01

    Previous researches on network adequacy mostly focused on the measurements of the system reliability caused by component failures, but under market environment impact of congestion on network adequacy must be considered. Through the research on new features of power network transmission under market environment, different states of power network transmission are defined. The indices to measure transmission line congestion are proposed to evaluate the inadequacy of network transmission capacity and apply in the expansion planning and operation schedules of power grid. Based on Monte Carlo method a model to calculate the adequacy indices is built. Considering various uncertainty factors, market simulation of IEEE 24-bus system and simulation calculation are performed, and results of simulation and calculation show that the proposed indices can effectively recognize the bottlenecks during transmission congestion. The line congestion risk index defined in this paper can be use to evaluate the risk of transmission congestion, and it is also available to constitute new criterion in the expension planning and to offer reference for congestion management.%通过研究市场环境下电网传输的新特点,定义了电网传输的不同状态.提出了衡量线路阻塞程度的指标,用于评价电网传输能力的不充裕性,并应用于电力系统的扩展规划和运行计划.基于蒙特卡罗方法建立了计算充裕度指标的模型,考虑各类不确定性因素,对IEEE-24节点系统进行了市场模拟和仿真计算,结果表明,所提指标能有效识别电网传输中的瓶颈.线路阻塞风险指标可评估输电阻塞的风险,在电网规划中可构成新的规划准则并为阻塞管理提供依据.

  9. 14 CFR 137.51 - Operation over congested areas: General.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Operation over congested areas: General... AGRICULTURAL AIRCRAFT OPERATIONS Operating Rules § 137.51 Operation over congested areas: General. (a) Notwithstanding part 91 of this chapter, an aircraft may be operated over a congested area at altitudes...

  10. Driving with a congestion assistant : mental workload and acceptance

    NARCIS (Netherlands)

    Brookhuis, K.A.; Driel, C. J.G. van; Hof, T.; Arem, B. van; Hoedemaeker, M.

    2009-01-01

    New driver support systems are developed and introduced to the market at increasing speed. In conditions of traffic congestion drivers may be supported by a" Congestion Assistant", a system that combines the features of a Congestion Warning System (acoustic warning and gas pedal counterforce) and a

  11. Mental workload while driving with a Congestion Assistant

    NARCIS (Netherlands)

    Hof, T.; Driel, C.J.G. van Van; Arem, B. van; Hoedemaeker, D.M.; Brookhuis, K.A.

    2006-01-01

    New driver support systems are developed and introduced to the market at increasing speed. In conditions of traffic congestion drivers may be supported by a “Congestion Assistant”, a system that combines the features of Congestion Warning System (acoustic warning and gaspedal counterforce) and Stop-

  12. Multilingual Database Management System: A Performance Evaluation

    Directory of Open Access Journals (Sweden)

    Nurul H.M. Saad

    2011-01-01

    Full Text Available Problem statement: The use of English as well as Arabic language is increasingly evident in the aspects of international business and finance. This study explored the management of multilingual data in multilingual system, to cater two or more different speakers of Internet users. Approach: The proposed method divided into two ends: The front-end that consisted of the Client and the Translator components and the back-end where the management module and the database located. In this method, a single encoded table required to store information and corresponding dictionaries needed to store the multilingual data. The proposed method based on the framework presented in previous work with some modification to suit with characteristics of chosen languages. Results: Experimental evaluation was performed in storage requirement and mathematical analysis had been used to show the time of each database operations for both of the traditional and the proposed method. Conclusion/Recommendations: The proposed method found to be consistently performed well in the developed multilingual system.

  13. Evaluation and management of early virological failure.

    Science.gov (United States)

    Sax, Paul E

    2006-09-01

    To describe the causes, evaluation, and management of early virological failure in patients treated with their first antiretroviral regimen. Combination antiretroviral therapy predictably induces a rapid virological response, with the majority of patients achieving an undetectable HIV-RNA load by week 24. In clinical trials and cohorts, rates of virological suppression have improved over time. Poor adherence to therapy remains the most common cause of virological failure, and genotype resistance testing is a critical step in evaluating the optimal subsequent approach. Most studies suggest that transient HIV-RNA elevations do not warrant changing treatment, and may be a consequence of laboratory variation. For those who experience virological failure, resistance to individual components of the antiretroviral regimen is dependent on the initial choice of treatment. Once virological failure is confirmed and adherence issues addressed, a prompt change in treatment is warranted to limit the selection of further drug resistance. Resistance that occurs with early virological failure follows typical patterns, with limited resistance to most antiretroviral agents in the nucleoside reverse transcriptase and protease inhibitor classes. The likelihood of achieving virological suppression with subsequent regimens should be high so long as adherence can be assured.

  14. An Evaluation of Traffic Management at ISF Academy on Kong Sin Wan Road

    Science.gov (United States)

    Lu, M.

    2016-12-01

    The ISF Academy, a school with 1500 students, is located on Kong Sin Wan Road. The majority of students from the academy commute to school every morning by private cars, school buses and other public transportation. For the past few years, the school management team has been imposing traffic management regulations to alleviate and minimize traffic congestion in the nearby area. In spite of that, traffic management on Kong Sin Wan Road is fairly limited and inadequate, resulting in congestion at the start and finish of the school day. As a school, we are dedicated to reduce and mitigate the number of private cars and school buses, as well as to control carbon dioxide emissions from the variety of vehicles. In order to implement strategies to make improvements to the current traffic management system, we, as a school, aim to establish a systematic approach to calculate and model the number of private cars, EV cars, plug-in hybrids and school buses flowing near the ISF campus every day, and the number of students on each vehicle. According to the U.S Environmental Protection Agency (EPA), the average annual carbon dioxide emission for a typical passenger vehicle is 4.7 metric tons. By multiplying the average carbon dioxide emission by the number of cars coming to campus every morning, we will gain a better understanding of the amount of carbon dioxide emitted from school vehicles. To extend the research, we will design a survey to investigate and encourage carpooling between families and students who live close, in order to combat and relieve rising traffic congestion and minimize cars crowding the roads. The traffic study project will not only help the school community create a more environment-friendly campus, but also improve the traffic congestion around the school area.

  15. Abnormal uterine bleeding after ovarian vein embolotherapy for pelvic congestion syndrome:Case report and review of literature

    Institute of Scientific and Technical Information of China (English)

    Mostafa A. Borahay; Gokhan S. Kilic; Mary C. Haver

    2012-01-01

    Ovarian vein embolotherapy is a relatively new treatment for pelvic congestion syndrome that is claimed to be safe and effective.A36-year-old woman underwent ovarian(without internal iliac) vein embolotherapy for pelvic congestion syndrome.Her pain was improved following the procedure.Within three months of the procedure, she started experiencing distressing abnormal uterine bleeding.Specifically, she developed profuse bleeding after intercourse.After thorough evaluation and counseling, a total abdominal hysterectomy was eventually performed.The use of ovarian vein embolization for treatment of pelvic congestion syndrome may be associated with abnormal uterine bleeding.

  16. Comparative Analysis of Congestion Control Algorithms Using ns-2

    Directory of Open Access Journals (Sweden)

    Sanjeev Patel

    2011-09-01

    Full Text Available In order to curtail the escalating packet loss rates caused by an exponential increase in network traffic, active queue management techniques such as Random Early Detection (RED have come into picture. Flow Random Early Drop (FRED keeps state based on instantaneous queue occupancy of a given flow. FRED protects fragile flows by deterministically accepting flows from low bandwidth connections and fixes several shortcomings of RED by computing queue length during both arrival and departure of the packet. Stochastic Fair Queuing (SFQ ensures fair access to network resources and prevents a busty flow from consuming more than its fair share. In case of (Random Exponential Marking REM, the key idea is to decouple congestion measure from performance measure (loss, queue length or delay. Stabilized RED (SRED is another approach of detecting nonresponsive flows. In this paper, we have shown a comparative analysis of throughput, delay and queue length for the various congestion control algorithms RED, SFQ and REM. We also included the comparative analysis of loss rate having different bandwidth for these algorithms.

  17. Impacts of variable message signs on traffic congestion

    Institute of Scientific and Technical Information of China (English)

    SHANG HuaYan; HUANG HaiJun; GAO ZiYou

    2009-01-01

    The variable message signs (VMS) have been widely used in guiding and managing the dynamic traffic with development of intelligent transportation technologies. It is known that cell transmission model (CTM) can well reproduce such traffic dynamics as shock waves and jams. This paper presents a new method to estimate the route travel times by using the CTM in conjunction with a Iogit-based route choice rule. The impacts of VMS on a two-route scenario with recurrent and non-recurrent traffic con-gestion are numerically investigated by analyzing the changes of route flow and travel time. Simulation results show that in networks with suitable long links, the VMS can positively influence travelers' deci-sion making so as to improve the system performance. For non-recurrent congestion, the value space of the route choice parameter that affects the flow distribution between two routes is narrower in the case of high traffic demand than that in the low demand case.

  18. Can complexity decrease in congestive heart failure?

    Science.gov (United States)

    Mukherjee, Sayan; Palit, Sanjay Kumar; Banerjee, Santo; Ariffin, M. R. K.; Rondoni, Lamberto; Bhattacharya, D. K.

    2015-12-01

    The complexity of a signal can be measured by the Recurrence period density entropy (RPDE) from the reconstructed phase space. We have chosen a window based RPDE method for the classification of signals, as RPDE is an average entropic measure of the whole phase space. We have observed the changes in the complexity in cardiac signals of normal healthy person (NHP) and congestive heart failure patients (CHFP). The results show that the cardiac dynamics of a healthy subject is more complex and random compare to the same for a heart failure patient, whose dynamics is more deterministic. We have constructed a general threshold to distinguish the border line between a healthy and a congestive heart failure dynamics. The results may be useful for wide range for physiological and biomedical analysis.

  19. Congestion Control Algorithm for Resilient Packet Ring

    Institute of Scientific and Technical Information of China (English)

    孔红伟; 葛宁; 阮方; 冯重熙

    2003-01-01

    A congestion control algorithm is proposed for resilient packet ring (RPR) in this paper. In thisalgorithm, nonlinear explicit rate feedback control is used to ensure fast convergence and smooth equilibriumbehavior. The algorithm combines explicit rate control with a deficit round robin (DRR) scheduler, which notonly ensures fairness, but also avoids the implementation difficulties of explicit rate control algorithms. Thealgorithm has good features of fairness, fast convergence, smooth equilibrium, Iow queue depth, and easyimplementation. It is insensitive to the loss of congestion control packets and can adapt to a wide range of linkrates and network scales. It has solved the unbalanced traffic problem of spatial reuse protocol (SRP). Thealgorithm can be implemented on the multi-access control layer of RPR nodes to ensure fair and efficient accessof the best-effort traffic.

  20. Alleviate Cellular Congestion Through Opportunistic Trough Filling

    Directory of Open Access Journals (Sweden)

    Yichuan Wang

    2014-04-01

    Full Text Available The demand for cellular data service has been skyrocketing since the debut of data-intensive smart phones and touchpads. However, not all data are created equal. Many popular applications on mobile devices, such as email synchronization and social network updates, are delay tolerant. In addition, cellular load varies significantly in both large and small time scales. To alleviate network congestion and improve network performance, we present a set of opportunistic trough filling schemes that leverage the time-variation of network congestion and delay-tolerance of certain traffic in this paper. We consider average delay, deadline, and clearance time as the performance metrics. Simulation results show promising performance improvement over the standard schemes. The work shed lights on addressing the pressing issue of cellular overload.

  1. Vehicle Traffic Congestion Estimation Based on RFID

    OpenAIRE

    Al-Naima, Fawzi M.; Hamd, Hassan A.

    2012-01-01

    Due to the proliferation in the number of vehicles on the road, traffic problems are bound to exist. Therefore, the use of Intelligent Transportation Systems (ITS) has become mandatory for obtaining traffic information from roads. Radio Frequency Identification (RFID) technology has been used to obtain vehicles’ IDs (tag ID) from RFID readers and to collect traffic information in real‐time. This paper proposes a simulation system for the Vehicle Traffic Congestion Estimation (VTCE) based on R...

  2. Proposal and Evaluation of Management Method for College Mechatronics Education Applying the Project Management

    Science.gov (United States)

    Ando, Yoshinobu; Eguchi, Yuya; Mizukawa, Makoto

    In this research, we proposed and evaluated a management method of college mechatronics education. We applied the project management to college mechatronics education. We practiced our management method to the seminar “Microcomputer Seminar” for 3rd grade students who belong to Department of Electrical Engineering, Shibaura Institute of Technology. We succeeded in management of Microcomputer Seminar in 2006. We obtained the good evaluation for our management method by means of questionnaire.

  3. A model to evaluate quality and effectiveness of disease management.

    Science.gov (United States)

    Lemmens, K M M; Nieboer, A P; van Schayck, C P; Asin, J D; Huijsman, R

    2008-12-01

    Disease management has emerged as a new strategy to enhance quality of care for patients suffering from chronic conditions, and to control healthcare costs. So far, however, the effects of this strategy remain unclear. Although current models define the concept of disease management, they do not provide a systematic development or an explanatory theory of how disease management affects the outcomes of care. The objective of this paper is to present a framework for valid evaluation of disease-management initiatives. The evaluation model is built on two pillars of disease management: patient-related and professional-directed interventions. The effectiveness of these interventions is thought to be affected by the organisational design of the healthcare system. Disease management requires a multifaceted approach; hence disease-management programme evaluations should focus on the effects of multiple interventions, namely patient-related, professional-directed and organisational interventions. The framework has been built upon the conceptualisation of these disease-management interventions. Analysis of the underlying mechanisms of these interventions revealed that learning and behavioural theories support the core assumptions of disease management. The evaluation model can be used to identify the components of disease-management programmes and the mechanisms behind them, making valid comparison feasible. In addition, this model links the programme interventions to indicators that can be used to evaluate the disease-management programme. Consistent use of this framework will enable comparisons among disease-management programmes and outcomes in evaluation research.

  4. 关于城市交通拥堵的几点思考%Some thinking of city traffic congestion

    Institute of Scientific and Technical Information of China (English)

    常永峰

    2012-01-01

    Through the cause analysis on the current situation of traffic congestion,this paper illustrated the harm of traffic congestion,finally according to our country current situation of city traffic congestion put forward relative measures to solve traffic congestion,provided certain reference to promote our country traffic management level.%通过对交通拥堵的现状以及原因分析,说明了交通拥堵的坏处,最后针对我国城市的交通现状提出了解决城市拥堵的相对措施,希望能够为提升我国交通管理水平提供一定的参考。

  5. Evaluating Biological Robustness of Innovative Management Alternatives

    NARCIS (Netherlands)

    Bastardie, F.; Baudron, A.; Bilocca, R.; Boje, J.; Bult, T.P.; Garcia, D.; Hintzen, N.T.

    2009-01-01

    The influence of innovative management alternatives (participatory governance, effort management, decision rules) on biological robustness (BR) in various fisheries relevant to the EU (Baltic, Western Shelf, Faroe Islands, North Sea), was investigated with a numerical simulation model developed in t

  6. Onset of traffic congestion in complex networks.

    Science.gov (United States)

    Zhao, Liang; Lai, Ying-Cheng; Park, Kwangho; Ye, Nong

    2005-02-01

    Free traffic flow on a complex network is key to its normal and efficient functioning. Recent works indicate that many realistic networks possess connecting topologies with a scale-free feature: the probability distribution of the number of links at nodes, or the degree distribution, contains a power-law component. A natural question is then how the topology influences the dynamics of traffic flow on a complex network. Here we present two models to address this question, taking into account the network topology, the information-generating rate, and the information-processing capacity of individual nodes. For each model, we study four kinds of networks: scale-free, random, and regular networks and Cayley trees. In the first model, the capacity of packet delivery of each node is proportional to its number of links, while in the second model, it is proportional to the number of shortest paths passing through the node. We find, in both models, that there is a critical rate of information generation, below which the network traffic is free but above which traffic congestion occurs. Theoretical estimates are given for the critical point. For the first model, scale-free networks and random networks are found to be more tolerant to congestion. For the second model, the congestion condition is independent of network size and topology, suggesting that this model may be practically useful for designing communication protocols.

  7. Changes in absolute and relative importance in the prognostic value of left ventricular systolic function and congestive heart failure after acute myocardial infarction. TRACE Study Group. Trandolapril Cardiac Evaluation

    DEFF Research Database (Denmark)

    Køber, L; Torp-Pedersen, C; Jørgensen, S;

    1998-01-01

    ) by echocardiography, was assessed in 6,676 consecutive patients with an enzyme-confirmed AMI. So that changes in the prognostic value of WMI or CHF could be studied, separate analyses were performed at selected time periods. Average monthly mortality (deaths per 100 patients per month) was determined from life......Changes in the importance of left ventricular (LV) systolic dysfunction and congestive heart failure (CHF) with time after an acute myocardial infarction (AMI) after the introduction of thrombolytic therapy have not been studied. LV systolic function, measured as wall motion index (WMI...... dysfunction or CHF, monthly mortality was high during the first month (18.3 +/- 1.6% and 20.2 +/- 1.6%, respectively), decreased during the first year, and was stable thereafter (0.8 +/- 0.1% and 1.0 +/- 0.1%, respectively, average monthly mortality after year 3). The relative risk of LV dysfunction decreased...

  8. Evaluation of urban freight transport management measures

    Directory of Open Access Journals (Sweden)

    Daniel Kaszubowski

    2012-09-01

    Full Text Available Background: Problems with urban freight traffic in downtown areas emerge in parallel with the growth of motorization and changes in consumption patterns. Supply chains become more and more dependent on small and frequent deliveries. It is a problem common for most modern cities and one that requires tailor-made solutions which meet local requirements and can be extended, if necessary. Methods: An extensive literature review was conducted to obtain a comprehensive overview of existing urban freight related problems and possible solutions. The specificity of the problem required a broad approach including an analysis of many case studies from European cities and gathering the theoretical background. On this basis a general set of freight related measures was selected for evaluation. Because of the complexity of both the problem and its solutions an adequate method of evaluation was needed. The method had to be flexible and offer an understandable and manageable structure. The analytic network process (ANP was selected for this task. It is a multi-criteria decision making method used in complex decisions, which can measure tangible and intangible factors. The author's aim was to build a sufficiently detailed model that ensures reliable results and accomplishes the goals of the main actors and of sustainable city transport policy. Results and Conclusions: The analysis showed that given the current state of development of urban freight traffic in Gdansk, the situation can be rationalised with regulatory measures. Only well balanced and carefully implemented measures have the potential to rationalize urban freight transport without disturbing the city's economic growth. They have to be prepared in advance on the basis of a continuous analysis of the urban transport system. It is important to involve all actors in the development of more advanced measures in a bottom-up planning process. Otherwise, the risk is that overly complicated solutions without

  9. An Evaluation of Management Training and Coaching

    Science.gov (United States)

    Berg, Morten Emil; Karlsen, Jan Terje

    2012-01-01

    Purpose: The focus of this paper is on management training and development. The purpose has been to address how coaching can be applied to learn about leadership tools and what effect this has on management behaviour and development. Design/methodology/approach: This is a qualitative case study of a management development program. The empirical…

  10. Integrative Medical Care Plus Mindfulness Training for Patients With Congestive Heart Failure: Proof of Concept.

    Science.gov (United States)

    Kemper, Kathi J; Carmin, Cheryl; Mehta, Bella; Binkley, Phillip

    2016-10-01

    Congestive heart failure (CHF) has a high rate of morbidity and mortality. It is often accompanied by other medical and psychosocial comorbidities that complicate treatment and adherence. We conducted a proof of concept pilot project to determine the feasibility of providing integrative group medical visits plus mindfulness training for patients recently discharged with CHF. Patients were eligible if they had been discharged from an inpatient stay for CHF within the 12 months prior to the new program. The Compassionate Approach to Lifestyle and Mind-Body (CALM) Skills for Patients with CHF consisted of 8 weekly visits focusing on patient education about medications, diet, exercise, sleep, and stress management; group support; and training in mind-body skills such as mindfulness, self-compassion, and loving-kindness. Over two 8-week sessions, 8/11 (73%) patients completed at least 4 visits. The patients had an average age of 57 years. The most common comorbidities were weight gain, sleep problems, and fatigue. After the sessions, 100% of patients planned to make changes to their diet, exercise, and stress management practices. Over half of the patients who met with a pharmacist had a medication-related problem. Improvements were observed in depression, fatigue, and satisfaction with life. Integrative group visits focusing on healthy lifestyle, support, and skill-building are feasible even among CHF patients and should be evaluated in controlled trials as a patient-centered approach to improving outcomes related to improving medication management, depression, fatigue, and quality of life.

  11. A NEW CASCADING FAILURE MODEL WITH DELAY TIME IN CONGESTED COMPLEX NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Jian WANG; Yanheng LIU; Yu JIAO

    2009-01-01

    Cascading failures often occur in congested complex networks. Cascading failures can be expressed as a three-phase process: generation, diffusion, and dissipation of congestion. Different from the betweenness centrality, a congestion function is proposed to represent the extent of congestion on a given node. Inspired by the restart process of a node, we introduce the concept of "delay time," during which the overloaded node cannot receive or forward any traffic, so an intergradation between permanent removal and nonremoval is built and the flexibility of the presented model is demonstrated. Considering the connectivity of a network before and after cascading failures is not cracked because the overloaded node are not removed from network permanently in our model, a new evaluation function of network efficiency is also proposed to measure the damage caused by cascading failures. Finally, we investigate the effects of network structure and size, delay time, processing ability, and traffic generation speed on congestion propagation. Cascading processes composed of three phases and some factors affecting cascade propagation are uncovered as well.

  12. Optimal Tradable Credits Scheme and Congestion Pricing with the Efficiency Analysis to Congestion

    Directory of Open Access Journals (Sweden)

    Ge Gao

    2015-01-01

    Full Text Available We allow for three traffic scenarios: the tradable credits scheme, congestion pricing, and no traffic measure. The utility functions of different modes (car, bus, and bicycle are developed by considering the income’s impact on travelers’ behaviors. Their purpose is to analyze the demand distribution of different modes. A social optimization model is built aiming at maximizing the social welfare. The optimal tradable credits scheme (distribution of credits, credits charging, and the credit price, congestion pricing fees, bus frequency, and bus fare are obtained by solving the model. Mode choice behavior under the tradable credits scheme is also studied. Numerical examples are presented to demonstrate the model’s availability and explore the effects of the three schemes on traffic system’s performance. Results show congestion pricing would earn more social welfare than the other traffic measures. However, tradable credits scheme will give travelers more consumer surplus than congestion pricing. Travelers’ consumer surplus with congestion pricing is the minimum, which injures the travelers’ benefits. Tradable credits scheme is considered the best scenario by comparing the three scenarios’ efficiency.

  13. Sexual behaviors in children: evaluation and management.

    Science.gov (United States)

    Kellogg, Nancy D

    2010-11-15

    Sexual behaviors in children are common, occurring in 42 to 73 percent of children by the time they reach 13 years of age. Developmentally appropriate behavior that is common and frequently observed in children includes trying to view another person's genitals or breasts, standing too close to other persons, and touching their own genitals. Sexual behaviors become less common, less frequent, or more covert after five years of age. Sexual behavior problems are defined as developmentally inappropriate or intrusive sexual acts that typically involve coercion or distress. Such behaviors should be evaluated within the context of other emotional and behavior disorders, socialization difficulties, and family dysfunction, including violence, abuse, and neglect. Although many children with sexual behavior problems have a history of sexual abuse, most children who have been sexually abused do not develop sexual behavior problems. Children who have been sexually abused at a younger age, who have been abused by a family member, or whose abuse involved penetration are at greater risk of developing sexual behavior problems. Although age-appropriate behaviors are managed primarily through reassurance and education of the parent about appropriate behavior redirection, sexual behavior problems often require further assessment and may necessitate a referral to child protective services for suspected abuse or neglect.

  14. An economic evaluation of solar radiation management

    Energy Technology Data Exchange (ETDEWEB)

    Aaheim, Asbjørn; Romstad, Bård; Wei, Taoyuan [CICERO — Center for International Climate and Environmental Research Oslo (Norway); Kristjánsson, Jón Egill; Muri, Helene [Department of Geosciences, University of Oslo (Norway); Niemeier, Ulrike; Schmidt, Hauke [Max Planck Institute for Meteorology, Hamburg (Germany)

    2015-11-01

    Economic evaluations of solar radiation management (SRM) usually assume that the temperature will be stabilized, with no economic impacts of climate change, but with possible side-effects. We know from experiments with climate models, however, that unlike emission control the spatial and temporal distributions of temperature, precipitation and wind conditions will change. Hence, SRM may have economic consequences under a stabilization of global mean temperature even if side-effects other than those related to the climatic responses are disregarded. This paper addresses the economic impacts of implementing two SRM technologies; stratospheric sulfur injection and marine cloud brightening. By the use of a computable general equilibrium model, we estimate the economic impacts of climatic responses based on the results from two earth system models, MPI-ESM and NorESM. We find that under a moderately increasing greenhouse-gas concentration path, RCP4.5, the economic benefits of implementing climate engineering are small, and may become negative. Global GDP increases in three of the four experiments and all experiments include regions where the benefits from climate engineering are negative.

  15. Evaluating participation in water resource management: A review

    Science.gov (United States)

    Carr, G.; BlöSchl, G.; Loucks, D. P.

    2012-11-01

    Key documents such as the European Water Framework Directive and the U.S. Clean Water Act state that public and stakeholder participation in water resource management is required. Participation aims to enhance resource management and involve individuals and groups in a democratic way. Evaluation of participatory programs and projects is necessary to assess whether these objectives are being achieved and to identify how participatory programs and projects can be improved. The different methods of evaluation can be classified into three groups: (i) process evaluation assesses the quality of participation process, for example, whether it is legitimate and promotes equal power between participants, (ii) intermediary outcome evaluation assesses the achievement of mainly nontangible outcomes, such as trust and communication, as well as short- to medium-term tangible outcomes, such as agreements and institutional change, and (iii) resource management outcome evaluation assesses the achievement of changes in resource management, such as water quality improvements. Process evaluation forms a major component of the literature but can rarely indicate whether a participation program improves water resource management. Resource management outcome evaluation is challenging because resource changes often emerge beyond the typical period covered by the evaluation and because changes cannot always be clearly related to participation activities. Intermediary outcome evaluation has been given less attention than process evaluation but can identify some real achievements and side benefits that emerge through participation. This review suggests that intermediary outcome evaluation should play a more important role in evaluating participation in water resource management.

  16. Evaluation of Performance of Background Traffic-based CMT-SCTP with Active Queue Management Algorithms

    Directory of Open Access Journals (Sweden)

    Meifang Shen

    2012-11-01

    Full Text Available Existing researches on performance analysis of SCTPs Concurrent Multipath Transfer (CMT-SCTP usually use DropTail algorithm as queue management algorithm without considering the impact of the background traffic. However, the background traffic of realistic network environments has an important impact on the QoS of SCTP. Besides, more and more Active Queue Management (AQM algorithms have been proposed as a router-based mechanism for early congestion detection to keep the stability of the whole network. This paper investigates the effect of background traffic on the performance of CMT-SCTP, and evaluates the performance of CMT-SCTP under two realistic simulation topologies with reasonable background traffic and different AQM algorithms in NS-2. The simulation results show that: 1 the performance of CMT-SCTP depends on characteristic of background traffic; and 2 the different AQM algorithms used as queue management algorithm under same background traffic have the different effects. Finally, this paper summarizes the proposals to satisfy the QoS requirements in terms of throughput, end-to-end packet delay and loss rate. Since CMT-PF2 is recommended by RFC4960 but without taking impact of cross traffic into account. In the second part, we use the most promising topology which meets the developing network and base on result of analysis mentioned in the first part to analyze the performance CMT-PF1/2/3/4 played respectively, in this part, the most common scenario, symmetric CMT-SCTP, is adopted and CMT-PF algorithm is turned on. A conclusion had been nailed down that, CMT-PF3 can get more advantage in terms of average throughput than CMT-PF2 which is recommended by RFC4960. Per reasonable analyzing, we lastly recommend a more reasonable resolution for realistic network in order to reaching more satisfied QoS.

  17. 动态血压监测在心力衰竭患者病情评估中的价值%Value of ambulatory blood pressure monitoring in severity evaluation of patients with congestive heart failure

    Institute of Scientific and Technical Information of China (English)

    邰胜; 刘志华

    2013-01-01

    Objective To research the value of ambulatory blood pressure monitoring (ABPM) for severity evaluation of patients with congestive heart failure(CHF). Methods A total of 92 inpatients with CHF were enrolled into study, all experienced 24 h ambulatory blood pressure monitoring and were divided into different groups by New York Heart Association(NYHA) functional class. Selected 72 inpatients and outpatients with the basic heart disease but no CHF during the same period served as control group. The relationship between the parameters of ABPM and the NYHA class of CHF was explored. Results The day systolic blood pressure (DSBP), day diastolic blood pressure (DDBP) , 24-hour mean blood pressure (24hMBP) , day mean blood pressure (DMBP) , day diastolic blood pressure variability(DDBPV) of CHF were significantly lower than those of control group( P <0. 01) ;DSBP(116. 2 + 17. 8) mmHg vs (123. 9 + 14. 5) mmHg,DDBP(69. 5 +10. 2) mmHg vs (75. 9 + 9. 7) mmHg,24hMBP(89. 4 + 12. 5) mmHg vs (95. 9 + 11.4) mmHg,DMBP(90. 4 + 13. 5) mmHg vs (100.2 + 11. 5) mmHg,DDBPV(8. 5 + 2. 4) mmHg vs (10.4 + 2. 4) mmHg,and 24 h systolic blood pressure(24hSBP) ,DSBP,night systolic blood pressure(NSBP) ,DDBP,24hMBP, DMBP, night mean blood pressure ( NMBP) , 24 h pulse pressure (24hPP) , day pulse pressure (DPP) , night pulse pressure(NPP) of NYHA Ⅳ were significantly lower than those of NYHA Ⅱ and(or) Ⅲ ( P <0. 01). 24hSBP, 24hDBP,24hMBP, 24hPP, 24 h systolic blood pressure variability and NYHA class presented obviously negative correlation P <0. 05 or <0. 01). Conclusion DSBP,DDBP,24hMBP,DMBP,and DDBPV in CHF were significantly lower than those in control group. Blood pressure decreased with the severity of CHF. 24hSBP, DSBP, NSBP, DDBP, 24hMBP, DMBP, NMBP,24hPP,DPP, NPP of NYHA Ⅳ were lower than those of NYHA Ⅱ and Ⅲ.%目的 研究动态血压监测在心力衰竭患者病情评估中的价值.方法 92例心力衰竭患者,均行动态血压监测(ABPM),并准确记录监测时的

  18. Congestion Control in WMSNs by Reducing Congestion and Free Resources to Set Accurate Rates and Priority

    Directory of Open Access Journals (Sweden)

    Akbar Majidi

    2014-08-01

    Full Text Available The main intention of this paper is focus on mechanism for reducing congestion in the network by free resources to set accurate rates and priority data needs. If two nodes send their packets in the shortest path to the parent node in a crowded place, a source node must prioritize the data and uses data that have lower priorities of a suitable detour nodes consisting of low or non- active consciously. The proposed algorithm is applied to the nodes near the base station (which convey more traffic after the congestion detection mechanism detected the congestion. Obtained results from simulation test done by NS-2 simulator demonstrate the innovation and validity of proposed method with better performance in comparison with CCF, PCCP and DCCP protocols.

  19. Input-Output Modeling and Control of the Departure Process of Congested Airports

    Science.gov (United States)

    Pujet, Nicolas; Delcaire, Bertrand; Feron, Eric

    2003-01-01

    A simple queueing model of busy airport departure operations is proposed. This model is calibrated and validated using available runway configuration and traffic data. The model is then used to evaluate preliminary control schemes aimed at alleviating departure traffic congestion on the airport surface. The potential impact of these control strategies on direct operating costs, environmental costs and overall delay is quantified and discussed.

  20. A Dynamic Adaptive Layered Multicast Congestion Control Mechanism

    Institute of Scientific and Technical Information of China (English)

    REN Liyong; LU Xianliang; WEI Qingsong; ZHOU Xu

    2003-01-01

    To solve the problem that most of existing layered multicast protocols cannot adapt to dynamic network conditions because their layers are coarsely granulated and static, a new congestion control mechanism for dynamic adaptive layered multicast(DALM) is presented. In this mechanism, a novel feedback aggregating algorithm is put forward, which can dynamically determine the number of layers and the rate of each layer, and can efficiently improve network bandwidth utilization ratio.Additionally, because all layers is transmitted in only one group, the intricate and time-consuming internet group management protocol(IGMP) operations, caused by receiver joining a new layer or leaving the topmost subscribed layer, are thoroughly eliminated. And this mechanism also avoids other problems resulted from multiple groups. Simulation results show that DALM is adaptive and TCP friendly.

  1. Evaluation of the hypertension disease management program in Korea.

    Science.gov (United States)

    Kim, Younmi; Lee, Kunsei; Shin, Eunyoung; Kim, Hyeongsu; June, Kyung Ja

    2010-07-01

    This study evaluated how the Hypertension Disease Management Program (HDMP) affects patient's blood pressure, knowledge, health behaviors, and use of medical services. Evaluation was performed by 2 measures, which were before and after comparison within the management group (n = 210) and comparison between the management group and control group (n = 1050) in 2005. Systolic and diastolic blood pressure of management group significantly decreased from 137.5 and 86.0 mm Hg to 131.2 and 83.8 mm Hg (P management techniques significantly increased after HDMP. However, there was no significant difference in the use of medical service between the disease management group and the control group. This study showed that the HDMP improved lifestyle and reduced blood pressure on the disease management group, but changed neither medical costs nor use of medical services. Long-term evaluation should be performed to determine if the HDMP reduce medical costs and use of medical services.

  2. Evaluation of information and communication management software

    Directory of Open Access Journals (Sweden)

    Moseeva Natalia

    2012-02-01

    Full Text Available In article the basic techniques of an estimation of information-communication maintenance of management are considered. The new technique of estimation ICMM is developed. The choice of the most effective is spent information-communication maintenance of management, a communication profile of the organization, an information-communication matrix of the organization.

  3. Evaluation of information and communication management software

    OpenAIRE

    Moseeva Natalia; Moseeva Galina

    2012-01-01

    In article the basic techniques of an estimation of information-communication maintenance of management are considered. The new technique of estimation ICMM is developed. The choice of the most effective is spent information-communication maintenance of management, a communication profile of the organization, an information-communication matrix of the organization.

  4. Consumer Evaluations of Food Risk Management Quality in Europe

    NARCIS (Netherlands)

    Kleef, van E.; Houghton, J.R.; Krystallis, A.; Pfenning, U.; Rowe, G.; Dijk, van H.; Lans, van der I.A.; Frewer, L.J.

    2007-01-01

    In developing and implementing appropriate food risk management strategies, it is important to understand how consumers evaluate the quality of food risk management practices. The aim of this study is to model the underlying psychological factors influencing consumer evaluations of food risk managem

  5. The effects of congestion charging on road traffic casualties: a causal analysis using difference-in-difference estimation.

    Science.gov (United States)

    Li, Haojie; Graham, Daniel J; Majumdar, Arnab

    2012-11-01

    This paper aims to identify the impacts of the London congestion charge on road casualties within the central London charging zone. It develops a full difference-in-difference (DID) model that is integrated with generalized linear models, such as Poisson and Negative Binomial regression models. Covariates are included in the model to adjust for factors that violate the parallel trend assumption, which is critical in the DID model. The lower Bayesian Information Criterion value suggests that the full difference-in-difference model performs well in evaluating the relationship between road accidents and the London congestion charge as well as other socio-economic factors. After adjusting for a time trend and regional effects, the results show that the introduction of the London congestion charge has a significant influence on the incidence of road casualties. The congestion charge reduces the total number of car accidents, but is associated with an increase in two wheeled vehicle accidents.

  6. Analysis and evaluation of enterprise risk management capability elements

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Research on enterprise risk management capability is conducted with a view of discerning and processing risks, in which an evaluation index system and an evaluation model of enterprise risk management capabilities are constructed. The risk management capability consists of four aspects, i.e. risk identification capability, risk assessment capability, risk planning capability and risk control capability. Risk identification and assessment capabilities reflect the level of enterprises on finding and analyzing...

  7. Entrepreneur environment management behavior evaluation method derived from environmental economy.

    Science.gov (United States)

    Zhang, Lili; Hou, Xilin; Xi, Fengru

    2013-12-01

    Evaluation system can encourage and guide entrepreneurs, and impel them to perform well in environment management. An evaluation method based on advantage structure is established. It is used to analyze entrepreneur environment management behavior in China. Entrepreneur environment management behavior evaluation index system is constructed based on empirical research. Evaluation method of entrepreneurs is put forward, from the point of objective programming-theory to alert entrepreneurs concerned to think much of it, which means to take minimized objective function as comprehensive evaluation result and identify disadvantage structure pattern. Application research shows that overall behavior of Chinese entrepreneurs environmental management are good, specially, environment strategic behavior are best, environmental management behavior are second, cultural behavior ranks last. Application results show the efficiency and feasibility of this method.

  8. Congestion Measures for Organized Markets in the U.S.

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, Emily; Eto, Joseph H.

    2013-12-16

    Transmission lines deliver electricity that is generated at power plants to loads. When there is not sufficient transmission capacity to schedule or transport all desired electricity transfers, the transmission system is constrained, and the particular line, flowgate or interface is congested. While it is useful to measure congestion for several reasons—to identify where and how much congestion exists and how this changes over time, to determine whether or what to do about it, and to assess the effectiveness of actions taken—it is challenging to measure congestion in a meaningful and consistent way across markets or over time in the same market. This paper examines current public reporting of congestion measures for organized markets in the U.S., and what these measures can and cannot tell us about congestion across regions or over time in the same region.

  9. Advanced Congestive Heart Failure Associated With Disseminated Intravascular Coagulopathy.

    Science.gov (United States)

    Sarcon, Annahita; Liu, Xiaoli; Ton, David; Haywood, James; Hitchcock, Todd

    2015-01-01

    Background. Disseminated intravascular coagulopathy (DIC) is a complication of an underlying disease and not a primary illness. It is most commonly associated with sepsis, trauma, obstetrical complications, and malignancies. There are very few cases in the literature illustrating the association between DIC and congestive heart failure. Findings. In this report, we present a case of severe congestive heart failure, leading to biventricular thrombi and subsequently DIC. Conclusion. We suggest that the association between congestive heart failure and DIC is an underrecognized one. Congestive heart failure continues to remain a major cause of morbidity and mortality despite advances in medical therapies. Thus far, the precise role of coagulation factors in congestive heart failure is unknown. Further investigations are needed to elucidate the pathophysiology of congestive heart failure and coagulation factors.

  10. Traffic Congestion Model: Challenges and Opportunities

    Science.gov (United States)

    Enjat Munajat, M. D.; Munir, Rinaldi; Widyantoro, Dwi H.

    2017-01-01

    This paper discusses models to detect traffic congestion using two approaches: road detection and moving object detection. There are two methods proposed to detect roads and moving objects. The methods involve the detection of both moving and non-moving objects. The system presented in this paper is able to detect roads as well as moving objects. However, further development is needed to detect extreme road curves. The system presented in this paper is relatively inexpensive since it only uses one camera and capable of capturing satisfactorily detailed images.

  11. Congestive heart failure in acromegaly: A review of 6 cases

    OpenAIRE

    Dutta, P.; Das, S; Bhansali, A; S K Bhadada; B V Rajesh; Reddy, K. S.; Vaiphei, K; K. K. Mukherjee; Pathak, A.; Shah, V N

    2012-01-01

    Background: Though cardiac involvement is common in acromegaly, overt congestive heart failure is uncommon. Materials and Methods: This is retrospective analysis of hospital record between 1996 and 2007. We analyzed records of 150 consecutive patients with acromegaly. We included the patients with acromegaly those who had overt congestive heart failure either at presentation or during the course of illness for the present analysis. The diagnosis of acromegaly and congestive cardiac failure we...

  12. Breeding soundness evaluation and reproductive management in ...

    African Journals Online (AJOL)

    management of 33 sport horses (14 mares and 19 stallions) belonging to Palace. Administration ... Body weight was significantly correlated with girth both in mares ... and sub-fertility in the mares in particular such as aging, stress, inbreeding,.

  13. Theories of lean management: an empirical evaluation.

    Science.gov (United States)

    Handel, Michael J

    2014-03-01

    Debates within organization theory traditionally argued the relative merits of bureaucracy but today there is broad agreement across different perspectives that bureaucratic organization is inefficient and outmoded. Despite their differences, post-bureaucratic and neo-liberal theories argue that organizations with relatively flat hierarchies and low management overhead are better adapted to current market requirements. Post-bureaucratic theory also argues that employees, as well as firms, benefit from leaner management structures. This paper investigates trends in managerial leanness, proposed explanations for such trends, and the consequences of leanness for firms and employees. Although there is a trend toward flatter management hierarchies, there is only weak support for current claims regarding both the causes and consequences of lean management. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. 交通需求的顽固增长与合理归位--组团式城市空间结构、哑铃式拥堵及治理%Obstinate Increasing and Reasonable Locating of Traffic Demand:Clustered Urban Spatial Structure,Dumbbell-Style Congestion and Management

    Institute of Scientific and Technical Information of China (English)

    黄承锋; 刘晓萌; 丁银; 张媛媛

    2015-01-01

    Unlike ring structure style congestion of mono-centric city,the spatial characteristic of clustered urban traffic congestion represented by Chongqing is “dumbbell-style”,but there is the tendency of ring structure style congestion.Excessively “intensive”and “high”space utilization,scattered industry layout,separation of living and working place,excessive consumption of vehicles inevitably result in obstinate increasing of traffic demand.The clustered urban traffic congestion management should combine industry agglomeration and cluster characteristics, i.e.,to maintain and optimize cluster characteristics exclusive to city;to develop correlative industry agglomeration and cluster and to integrate cluster service function avoiding scattered industry layout caused by transportation facilitation among clusters;to develop tandem type spatial combination of TOD urban traffic-urban organization with greater capacity transportation connecting clusters;finally different industries should be located in different clusters,and correlative industry clusters and their people should be located in one cluster with harmonious co-exsitance of industries and clusters.%不同于单中心城市的“圈层式拥堵”,以重庆市为代表的组团式城市交通拥堵的空间特点是“哑铃式拥堵”,但有向“圈层式拥堵”发展的不良趋势;空间利用过密及单质化倾向、产业布局分散、职住分离、城镇化快速推进、汽车消费过度及其顽固性必然引致交通需求的顽固增长。组团式城市交通拥堵治理的方向应是产业聚集与组团特质相结合:维持、优化城区特有的组团特质,在组团空间内部形成关联产业群聚集并实现组团服务功能的融合,避免组团间的交通便利化导致的产业分散布局,组团间使用大容量交通进行连接,形成 TOD 式“城市交通—城市组织”的空间串联组合,最终形成不同产业归位于不同组团、

  15. Congestion Control Based on Reliable Transmission in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Hua Sun

    2014-03-01

    Full Text Available A new congestion control method is proposed in this paper. It makes use of the combination of buffer queue length and its variation rate to estimate the degree of congestion. It divides the node states and adopts various bandwidth allocation strategies according to different states, which ensures the reliable transmission of emergent information. Firstly, this paper introduces the queue model with priorities, divides the services according to different data flows and makes a detailed introduction on congestion adjustment mechanism based on the above information. The simulation experiment shows that the congestion control mechanism in this paper can ensure the reliable transmission of emergency information in monitoring sensor networks

  16. A Review of Router based Congestion Control Algorithms

    Directory of Open Access Journals (Sweden)

    Vandana Kushwaha

    2013-11-01

    Full Text Available This paper presents a study of Router based Congestion control approaches in wired network. As network is considered as a distributed system, any problem arises in such a system requires a distributed solution. Thus for good congestion control in the network we also need a solution distributed at source as well as router ends. The purpose of this study is to review the router based Congestion control research for wired network and characterize the different approaches to Congestion control design, by considering their advantages and limitations.

  17. Role of connectivity in congestion and decongestion in networks

    CERN Document Server

    Gupte, N; Gupte, Neelima; Singh, Brajendra K.

    2005-01-01

    We study network traffic dynamics in a two dimensional communication network with regular nodes and hubs. If the network experiences heavy message traffic, congestion occurs due to finite capacity of the nodes. We discuss strategies to manipulate hub capacity and hub connections to relieve congestion and define a coefficient of betweenness centrality (CBC), a direct measure of network traffic, which is useful for identifying hubs which are most likely to cause congestion. The addition of assortative connections to hubs of high CBC relieves congestion very efficiently.

  18. MINIMUM CONGESTION SPANNING TREES IN BIPARTITE AND RANDOM GRAPHS

    Institute of Scientific and Technical Information of China (English)

    M.L Ostrovskii

    2011-01-01

    The first problem considered in this article reads: is it possible to find upper estimates for the spanning tree congestion in bipartite graphs, which are better than those for general graphs? It is proved that there exists a bipartite version of the known graph with spanning tree congestion of order n3/2, where n is the number of vertices. The second problem is to estimate spanning tree congestion of random graphs. It is proved that the standard model of random graphs cannot be used to find graphs whose spanning tree congestion has order greater than n3/2.

  19. Green supply chain: Simulating road traffic congestion

    Science.gov (United States)

    Jalal, Muhammad Zulqarnain Hakim Abd; Nawawi, Mohd Kamal Mohd; Laailatul Hanim Mat Desa, Wan; Khalid, Ruzelan; Khalid Abduljabbar, Waleed; Ramli, Razamin

    2017-09-01

    With the increasing awareness of the consumers about environmental issues, businesses, households and governments increasingly want use green products and services which lead to green supply chain. This paper discusses a simulation study of a selected road traffic system that will contribute to the air pollution if in the congestion state. Road traffic congestion (RTC) can be caused by a temporary obstruction, a permanent capacity bottleneck in the network itself, and stochastic fluctuation in demand within a particular sector of the network, leading to spillback and queue propagation. A discrete-event simulation model is developed to represent the real traffic light control (TLC) system condition during peak hours. Certain performance measures such as average waiting time and queue length were measured using the simulation model. Existing system uses pre-set cycle time to control the light changes which is fixed time cycle. In this research, we test several other combination of pre-set cycle time with the objective to find the best system. In addition, we plan to use a combination of the pre-set cycle time and a proximity sensor which have the authority to manipulate the cycle time of the lights. The sensors work in such situation when the street seems to have less occupied vehicles, obviously it may not need a normal cycle for green light, and automatically change the cycle to street where vehicle is present.

  20. Impact of Incidents on Traffic Congestion in Dar es Salaam City

    Directory of Open Access Journals (Sweden)

    David Mfinanga

    2013-06-01

    Full Text Available Poorly managed traffic incidents have largely contributed to congestion and delay in the city of Dar es Salaam. A thorough understanding of travel delays caused by incidents is therefore essential for effective countermeasures against the increasing congestion. The method used to determine delays in this research is based on the deterministic queuing theory. Information on incidents was obtained from traffic surveys, traffic police and road users. Counting of the number of vehicles passing the incident location was done on incident and incident-free days. The cumulative traffic counts on incident and incident-free days were then calculated and used to plot the queuing diagram used to determine incident induced delay. This method turned out to be a useful tool for estimating incident induced delay in areas with less sophisticated equipment i.e. where there are no sensors, CCTV cameras, etc. The method provided good estimates of incident induced delay which may help planners and transportation officials in better understanding incident related congestion and in selecting more effective countermeasures against incident related traffic congestion in the city. It was found out that the effects of incidents were different for the different zones, types of incidents and the periods the incident occurred. In addition to the incident duration and the number of vehicles affected, the impact of incidents also depended on availability of alternative routes, number of lanes on the road, discipline of the driver in manoeuvring at incident location and traffic control at the scene.

  1. Approaching Incast Congestion with Multi-host Ethernet Controllers

    CERN Document Server

    Jereczek, Grzegorz Edmund; The ATLAS collaboration

    2017-01-01

    The bursty many-to-one communication pattern, typical for data acquisition systems, but also present in datacenter networks, is particularly demanding for commodity TCP/IP and Ethernet technologies. We expand our study of building incast-resistant networks based on software switches running on commercial-off-the-shelf servers. In this paper we provide the estimates for costs and physical area required to build such a network. Our estimates indicate that our proposed design offers significant cost advantage over traditional solutions, but higher space utilisation. Next, we show how the latter can be improved with multi-host Ethernet controllers, as an alternative to typical network interface cards. This can also make software switching easier to adapt in datacenter as a solution for incast congestion. We confirm the capabilities for incast-avoidance by evaluating the performance of a reference platform.

  2. Congestive heart failure and cognitive functioning amongst older adults

    Directory of Open Access Journals (Sweden)

    Almeida Osvaldo P.

    2001-01-01

    Full Text Available BACKGROUND: Congestive heart failure is associated with decline in quality of life and, possibly, cognitive functions such as memory and attention. AIMS: The present study was designed to investigate the presence of cognitive impairment amongst patients with congestive heart failure (CHF. We hypothesised that CHF patients would have lower scores than elderly controls on general measures of cognitive functioning. METHODS AND RESULTS: We examined a sample of 50 consecutive patients admitted to hospital with CHF functional class III/IV and a convenience sample of 30 older adults assessed at the outpatient service of geriatric medicine of a teaching hospital in São Paulo, Brazil. All subjects were interviewed with the Cambridge Examination for Mental Disorders of the Elderly (CAMDEX, as well as the neuropsychological battery of the CAMDEX (CAMCOG, Mini-Mental State Examination (MMSE, Trail Making A and B, Digit Span, Digit Symbol, and Letter Cancellation Test. All CHF patients had left ventricular ejection fraction (EF below 45% and all controls above 65%. The cognitive performance of CHF patients was significantly worse than controls for all cognitive assessments. Twenty-seven of 50 CHF patients had a MMSE total score lower than 24, compared with only 10/30 controls (p=0.073. Similarly, 36/49 and 9/30 CHF subjects and controls respectively had CAMCOG scores below 80 (p<0.001. Cognitive scores were significantly associated with EF, which was the most robust predictor of cognitive impairment according to the CAMCOG in a logistic regression model. CONCLUSION: Our results indicate that CHF is associated with significant levels of cognitive impairment and show that mental performance is, at least partly, a consequence of EF. Physicians should be prepared to assess the mental state of patients, as poor cognitive functioning may interfere with treatment compliance and management plan.

  3. Evaluation of Professional Cloud Password Management Tools

    DEFF Research Database (Denmark)

    Schougaard, Daniel; Dragoni, Nicola; Spognardi, Angelo

    2016-01-01

    Strong passwords have been preached since decades. However,lot of the regular users of IT systems resort to simple and repetitive passwords, especially nowadays in the "service era". To help alleviate this problem, a new class of software grew popular: password managers. Since their introduction...

  4. Preoperative evaluation : risk management and implementation aspects

    NARCIS (Netherlands)

    Klei, W.A. van

    2002-01-01

    In preoperative risk management the anesthesiologist uses diagnostic information to estimate the probability of outcomes and to decide on the anesthetic strategy in a particular patient. The aim of this thesis was explore to what extent simple patient characteristics, particularly obtained from

  5. An evaluation of location management procedures

    NARCIS (Netherlands)

    Baumann, Frank V.; Niemegeers, Ignas G.

    1994-01-01

    This paper gives a comparative description of two scenarios for location management in a mobile telecommunications system. The first scenario uses fixed location and paging areas. Mobiles perform a location update as they enter a new location area. The second scenario uses a time-out based location

  6. Evaluation of wildlife management through organic farming

    DEFF Research Database (Denmark)

    Topping, Christopher John

    2011-01-01

    Organic farming has often been suggested as a way of increasing biodiversity in agricultural landscapes, but literature reports a variable success. The drivers in play are multi-factorial and include the particular species groups under consideration, the precise form of organic management, the la...

  7. Preoperative evaluation : risk management and implementation aspects

    NARCIS (Netherlands)

    Klei, W.A. van

    2002-01-01

    In preoperative risk management the anesthesiologist uses diagnostic information to estimate the probability of outcomes and to decide on the anesthetic strategy in a particular patient. The aim of this thesis was explore to what extent simple patient characteristics, particularly obtained from preo

  8. How Might We Strengthen Evaluation Capacity to Manage Evaluation Contracts?

    Science.gov (United States)

    Newcomer, Kathryn

    2004-01-01

    The laudatory goal of evaluation capacity building is quite timely, given the spotlight on the potential use of program evaluation in the current environment which emphasizes performance reporting and evidence-based policy. A question that quickly comes to mind is: Where do you start? A seemingly reasonable starting point is to assess…

  9. Evaluation and management of acute vascular trauma.

    Science.gov (United States)

    Salazar, Gloria M M; Walker, T Gregory

    2009-06-01

    With the technical advances and the increasing availability of sophisticated imaging equipment, techniques, and protocols, and with continually evolving transcatheter endovascular therapies, minimally invasive imaging and treatment options are being routinely used for the clinical management of trauma patients. Thus, the primary treatment algorithm for managing acute vascular trauma now increasingly involves the interventional radiologist or other endovascular specialist. Endovascular techniques represent an attractive option for both stabilizing and definitively treating patients who have sustained significant trauma, with resultant vascular injury. Endovascular treatment frequently offers the benefit of a focused definitive therapy, even in the presence of massive hemorrhage that allows for preservation of major vessels or injured solid organs and serves as an alternative to an open surgical intervention. This article presents an overview of various endovascular techniques that can be used for trauma patients presenting with vascular injuries.

  10. Environmental evaluation of plastic waste management scenarios

    DEFF Research Database (Denmark)

    Rigamonti, L.; Grosso, M.; Møller, Jacob

    2014-01-01

    The management of the plastic fraction is one of the most debated issues in the discussion on integrated municipal solid waste systems. Both material and energy recovery can be performed on such a waste stream, and different separate collection schemes can be implemented. The aim of the paper...... is to contribute to the debate, based on the analysis of different plastic waste recovery routes. Five scenarios were defined and modelled with a life cycle assessment approach using the EASEWASTE model. In the baseline scenario (P0) the plastic is treated as residual waste and routed partly to incineration...... with energy recovery and partly to mechanical biological treatment. A range of potential improvements in plastic management is introduced in the other four scenarios (P1–P4). P1 includes a source separation of clean plastic fractions for material recycling, whereas P2 a source separation of mixed plastic...

  11. Empirical Study of Accepted Gap and Lane Change Duration within Arterial Traffic under Recurrent and Non-Recurrent Congestion

    Directory of Open Access Journals (Sweden)

    Saravanan Gurupackiam

    2012-12-01

    Full Text Available This paper investigated variations in accepted gaps and lane change duration on arterial under recurrent and non-recurrent congestion. Descriptive statistics and best-fit distributions were obtained for the two parameters for both traffic conditions. Hypothesis testing using Mann-Whitney U-Test showed that the means of accepted gaps and lane change durations were statistically different between the two types of traffic’ conditions. The study found that during non-recurrent congestion, drivers on an average accepted smaller gaps but took longer lane change durations. Based on the fact that the data were collected for the same flow-rate (70-90 vehicles/minute in both traffic conditions and based on the literature, the reason for the above findings could be that, drivers get more frustrated during non-recurring congestion that they accept smaller gaps. Drivers visiting the study location for game day (non-recurrent exhibit different driver behavioral characteristics when compared to regular commuters (recurrent which could have also contributed to the statistical differences in the lane changing characteristics of two types of congestion. These findings have direct implications on the lane changing parameters used in microscopic traffic simulation and also help transportation planners and managers to understand driver behavior during recurrent and non-recurrent congestion and better manage the facilities.

  12. Software Maintenance Management Evaluation and Continuous Improvement

    CERN Document Server

    April, Alain

    2008-01-01

    This book explores the domain of software maintenance management and provides road maps for improving software maintenance organizations. It describes full maintenance maturity models organized by levels 1, 2, and 3, which allow for benchmarking and continuous improvement paths. Goals for each key practice area are also provided, and the model presented is fully aligned with the architecture and framework of software development maturity models of CMMI and ISO 15504. It is complete with case studies, figures, tables, and graphs.

  13. M/M/∞ transience: Tail asymptotics of congestion periods

    NARCIS (Netherlands)

    Mandjes, M.; Roijers, F.

    2009-01-01

    The c-congestion period, defined as a time interval in which the number of customers is larger than c all the time, is a key quantity in the design of communication networks. Particularly in the setting of M/M/∞ systems, the analysis of the duration of the congestion period, Dc, has attra

  14. A congestion alleviated scheme in optical burst switching network

    Institute of Scientific and Technical Information of China (English)

    Gang Wang; Hongxiang Wang; Yuefeng Ji

    2008-01-01

    An optical burst switching (OBS) network platform is established with a ring topology of three nodes. A congestion alleviated scheme using advanced token protocol and wavelength tunable receivers is demonstrated to optimize the network platform. Experimental results testify that this scheme can resist collision at the level of 0.1% congestion rate.

  15. Congestion in planar graphs with demands on faces

    CERN Document Server

    Naves, Guyslain

    2010-01-01

    We give an algorithm to route a multicommodity flow in a planar graph $G$ with congestion $O(\\log k)$, where $k$ is the maximum number of terminals on the boundary of a face, when each demand edge lie on a face of $G$. We also show that our specific method cannot achieve a substantially better congestion.

  16. Evaluating the Predictive Validity of Graduate Management Admission Test Scores

    Science.gov (United States)

    Sireci, Stephen G.; Talento-Miller, Eileen

    2006-01-01

    Admissions data and first-year grade point average (GPA) data from 11 graduate management schools were analyzed to evaluate the predictive validity of Graduate Management Admission Test[R] (GMAT[R]) scores and the extent to which predictive validity held across sex and race/ethnicity. The results indicated GMAT verbal and quantitative scores had…

  17. Evaluating the Predictive Validity of Graduate Management Admission Test Scores

    Science.gov (United States)

    Sireci, Stephen G.; Talento-Miller, Eileen

    2006-01-01

    Admissions data and first-year grade point average (GPA) data from 11 graduate management schools were analyzed to evaluate the predictive validity of Graduate Management Admission Test[R] (GMAT[R]) scores and the extent to which predictive validity held across sex and race/ethnicity. The results indicated GMAT verbal and quantitative scores had…

  18. Evaluating the performance of survey-based operational management procedures

    NARCIS (Netherlands)

    Pomarede, M.; Hillary, R.; Ibaibarriaga, L.; Bogaards, J.A.; Apostolaki, P.

    2010-01-01

    The design and evaluation of survey-based management strategies is addressed in this article, using three case-study fisheries: North Sea herring, Bay of Biscay anchovy and North Sea cod, with a brief history and the main management issues with each fishery outlined. A range of operational managemen

  19. China Accomplishes International Evaluation on Science Funding and Management Performance

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    On the occasion of the 25th anniversary of National Natural Science Foundation of China(NSFC ), the International Evaluation on Science Funding and Management Performance,which is so far the largest comprehensive performance assessment on science funding and management of science and technology,is completed successfully.

  20. 28 CFR 549.63 - Initial medical evaluation and management.

    Science.gov (United States)

    2010-07-01

    ... MANAGEMENT MEDICAL SERVICES Hunger Strikes, Inmate § 549.63 Initial medical evaluation and management. (a... hunger strike: (1) Measure and record height and weight; (2) Take and record vital signs; (3) Urinalysis... weight and vital signs at least once every 24 hours while the inmate is on a hunger strike....

  1. PI Stabilization for Congestion Control of AQM Routers with Tuning Parameter Optimization

    Directory of Open Access Journals (Sweden)

    S. Chebli

    2016-09-01

    Full Text Available In this paper, we consider the problem of stabilizing network using a new proportional- integral (PI based congestion controller in active queue management (AQM router; with appropriate model approximation in the first order delay systems, we seek a stability region of the controller by using the Hermite- Biehler theorem, which isapplicable to quasipolynomials. A Genetic Algorithm technique is employed to derive optimal or near optimal PI controller parameters.

  2. Quantifying non-recurring congestion impact on secondary incidents using probe vehicle data

    OpenAIRE

    Park, Hyoshin; Haghani, Ali; Hamedi, Masoud

    2013-01-01

    As a significant cost and externality to economic efficiency, congestion is partly caused by traffic incidents. For more systematic, planned and coordinated incident management, quantifying a primary incident’s impact on secondary incidents is crucial and challenging. Many thresholds have been suggested in defining the secondary incidents, but there is no universal acceptance of a definition and corresponding set of measurement parameters. Static threshold methods cannot consider the actual r...

  3. Concurrent Imitation Dynamics in Congestion Games

    CERN Document Server

    Ackermann, Heiner; Fischer, Simon; Hoefer, Martin

    2008-01-01

    Imitating successful behavior is a natural and frequently applied approach to trust in when facing scenarios for which we have little or no experience upon which we can base our decision. In this paper, we consider such behavior in atomic congestion games. We propose to study concurrent imitation dynamics that emerge when each player samples another player and possibly imitates this agents' strategy if the anticipated latency gain is sufficiently large. Our main focus is on convergence properties. Using a potential function argument, we how that our dynamics converge in a monotonic fashion to stable states. In such a state none of the players can improve its latency by imitating somebody else. As our main result, we show rapid convergence to approximate equilibria. At an approximate equilibrium only a small fraction of agents sustains a latency significantly above or below average. In particular, imitation dynamics behave like fully polynomial time approximation schemes (FPTAS). Fixing all other parameters, t...

  4. DYNAMIC CONGESTION CONTROL IN WDM OPTICAL NETWORK

    Directory of Open Access Journals (Sweden)

    Sangita Samajpati

    2013-02-01

    Full Text Available This paper is based on Wavelength Division Multiplexing (WDM optical networking. In this optical networking, prior to data transfer, lightpath establishment between source and destination nodes is usually carried out through a wavelength reservation protocol. This wavelength is reserved corresponding to a route between the source and destination and the route is chosen following any standard routing protocol based on shortest path. The backward reservation protocol is implemented initially. A fixed connected and weighted network is considered. The inputs of this implementation are the fixed network itself and its corresponding shortest path matrix. After this initial level of implementation, the average node usage over a time period is calculated and various thresholds for node usage are considered. Above threshold value, request arriving at that path selects its next shortest path. This concept is implemented on various wavelengths. The output represents the performance issues of dynamic congestion control.

  5. Demand and Congestion in Multiplex Transportation Networks

    Science.gov (United States)

    al-Awwad, Zeyad; Jiang, Shan; González, Marta C.

    2016-01-01

    Urban transportation systems are multimodal, sociotechnical systems; however, while their multimodal aspect has received extensive attention in recent literature on multiplex networks, their sociotechnical aspect has been largely neglected. We present the first study of an urban transportation system using multiplex network analysis and validated Origin-Destination travel demand, with Riyadh’s planned metro as a case study. We develop methods for analyzing the impact of additional transportation layers on existing dynamics, and show that demand structure plays key quantitative and qualitative roles. There exist fundamental geometrical limits to the metro’s impact on traffic dynamics, and the bulk of environmental accrue at metro speeds only slightly faster than those planned. We develop a simple model for informing the use of additional, “feeder” layers to maximize reductions in global congestion. Our techniques are computationally practical, easily extensible to arbitrary transportation layers with complex transfer logic, and implementable in open-source software. PMID:27657738

  6. Local debris congestion in the geosynchronous environment with population augmentation

    Science.gov (United States)

    Anderson, Paul V.; Schaub, Hanspeter

    2014-02-01

    Forecasting of localized debris congestion in the geostationary (GEO) regime is performed to investigate how frequently near-miss events occur for each of the longitude slots in the GEO ring. The present-day resident space object (RSO) population at GEO is propagated forward in time to determine current debris congestion conditions, and new probability density functions that describe where GEO satellites are inserted into operational orbits are harnessed to assess longitude-dependent congestion in "business-as-usual" launch traffic, with and without re-orbiting at end-of-life. Congestion forecasting for a 50-year period is presented to illustrate the need for appropriately executed mitigation measures in the GEO ring. Results indicate that localized debris congestion will double within 50 years under current 80% re-orbiting success rates.

  7. Congestion Control Strategy for Opportunistic Network Based on Message Values

    Directory of Open Access Journals (Sweden)

    Deng-yin Zhang

    2014-05-01

    Full Text Available To solve the congestion problem in opportunistic networks, a congestion control strategy based on message deleting and transferring(DATM is proposed. The congested node calculates the storage value of each message according to the forwarding probability and TTL of message, then deletes the message with the minimum storage value and transfers the message with the minimum forwarding probability to neighboring nodes. The neighboring nodes calculate the receiving value of the message according to the forwarding probability and free buffer capacity of this message. The congested node transfers the message to the neighboring node with the maximum receiving value. The message will be deleted when there is no neighboring node to receive it. The algorithm is more targeted at deleting messages. Besides, it combines the strategy of transferring message. Therefore, it can deal with the congestion more efficiently. The message arrival rate is improved significantly and the end-to-end delay is also reduced to some extent.

  8. Public Attitudes Towards Policy Instruments for Congestion Mitigation in Shanghai

    Institute of Scientific and Technical Information of China (English)

    Chen Hongfeng; Xiao Pu; Feng Xiangzhao; Li Fen

    2008-01-01

    Congestion causes many externalities for the society, including time delays, excessive fuel consumption, air pollution, noise and safety concerns. In Shanghai, various policy options have been explored, piloted or applied; however, not all of them may be understood and accepted by the public. A survey was conducted to investigate people's attitudes towards several policy options. The main findings reveal that Shanghai residents are resistant to certain policies, such as congestion charges, higher parking charges in congested areas and car restrictions. Instead, they favor public transport provisions. The paper suggests that there is a case for promoting public transport and more efficient trips when the car ownership is still low, and for investing in a policy of educating the public on the 'true' costs and causes of congestion before embarking on an intensive policy of congestion charges or restrictions.

  9. Fluctuation-induced traffic congestion in heterogeneous networks

    CERN Document Server

    Stepanenko, A S; Constantinou, C C; Lerner, I V

    2011-01-01

    In studies of complex heterogeneous networks, particularly of the Internet, significant attention was paid to analyzing network failures caused by hardware faults or overload, where the network reaction was modeled as rerouting of traffic away from failed or congested elements. Here we model another type of the network reaction to congestion -- a sharp reduction of the input traffic rate through congested routes which occurs on much shorter time scales. We consider the onset of congestion in the Internet where local mismatch between demand and capacity results in traffic losses and show that it can be described as a phase transition characterized by strong non-Gaussian loss fluctuations at a mesoscopic time scale. The fluctuations, caused by noise in input traffic, are exacerbated by the heterogeneous nature of the network manifested in a scale-free load distribution. They result in the network strongly overreacting to the first signs of congestion by significantly reducing input traffic along the communicati...

  10. Agent Reward Shaping for Alleviating Traffic Congestion

    Science.gov (United States)

    Tumer, Kagan; Agogino, Adrian

    2006-01-01

    Traffic congestion problems provide a unique environment to study how multi-agent systems promote desired system level behavior. What is particularly interesting in this class of problems is that no individual action is intrinsically "bad" for the system but that combinations of actions among agents lead to undesirable outcomes, As a consequence, agents need to learn how to coordinate their actions with those of other agents, rather than learn a particular set of "good" actions. This problem is ubiquitous in various traffic problems, including selecting departure times for commuters, routes for airlines, and paths for data routers. In this paper we present a multi-agent approach to two traffic problems, where far each driver, an agent selects the most suitable action using reinforcement learning. The agent rewards are based on concepts from collectives and aim to provide the agents with rewards that are both easy to learn and that if learned, lead to good system level behavior. In the first problem, we study how agents learn the best departure times of drivers in a daily commuting environment and how following those departure times alleviates congestion. In the second problem, we study how agents learn to select desirable routes to improve traffic flow and minimize delays for. all drivers.. In both sets of experiments,. agents using collective-based rewards produced near optimal performance (93-96% of optimal) whereas agents using system rewards (63-68%) barely outperformed random action selection (62-64%) and agents using local rewards (48-72%) performed worse than random in some instances.

  11. Cross-layer active predictive congestion control protocol for wireless sensor networks.

    Science.gov (United States)

    Wan, Jiangwen; Xu, Xiaofeng; Feng, Renjian; Wu, Yinfeng

    2009-01-01

    In wireless sensor networks (WSNs), there are numerous factors that may cause network congestion problems, such as the many-to-one communication modes, mutual interference of wireless links, dynamic changes of network topology and the memory-restrained characteristics of nodes. All these factors result in a network being more vulnerable to congestion. In this paper, a cross-layer active predictive congestion control scheme (CL-APCC) for improving the performance of networks is proposed. Queuing theory is applied in the CL-APCC to analyze data flows of a single-node according to its memory status, combined with the analysis of the average occupied memory size of local networks. It also analyzes the current data change trends of local networks to forecast and actively adjust the sending rate of the node in the next period. In order to ensure the fairness and timeliness of the network, the IEEE 802.11 protocol is revised based on waiting time, the number of the node's neighbors and the original priority of data packets, which dynamically adjusts the sending priority of the node. The performance of CL-APCC, which is evaluated by extensive simulation experiments. is more efficient in solving the congestion in WSNs. Furthermore, it is clear that the proposed scheme has an outstanding advantage in terms of improving the fairness and lifetime of networks.

  12. Congestion Control Algorithm for Non-Safety Messages in Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Shamsul Jamel Elias

    2014-03-01

    Full Text Available Recent development in Congestion control mechanism on non-safety applications in Vehicular Ad Hoc Networks (VANETs have heightened the need for sustainable and reliable networks. However, the key challenges with this kind of applications are in the events of intermittent connectivity and data collisions. Comparatively, the event-driven effect on both safety and non-safety applications have critically are rely on delay and reliability. To date, the WAVE protocol in VANETs is derived from the IEEE 802.11pMAC protocol section. However, far to little attention has been given to non-safety applications for instance twitter, SMS services, internet services etc. Hence, Infotainment applications are not applying inter-vehicle communications (IVC provide services such as comfort and driving assistance. In spite of that, Roadside-Vehicle Communications (RVC caters for information concerning repair notifications, remote diagnostics, context information, navigation information, and alerts system. In this paper, we show design model for existing congestion control algorithms problems. The impact of the strategy are evaluated as opposed to the performance of non-safety applications. Furthermore, researches are centered on investigation the advantages and drawbacks of congestion control algorithms. In final analysis, we proposed non-safety applications approaches as our future research domain for solving the congestion problems

  13. Cross-Layer Active Predictive Congestion Control Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Yinfeng Wu

    2009-10-01

    Full Text Available In wireless sensor networks (WSNs, there are numerous factors that may cause network congestion problems, such as the many-to-one communication modes, mutual interference of wireless links, dynamic changes of network topology and the memory-restrained characteristics of nodes. All these factors result in a network being more vulnerable to congestion. In this paper, a cross-layer active predictive congestion control scheme (CL-APCC for improving the performance of networks is proposed. Queuing theory is applied in the CL-APCC to analyze data flows of a single-node according to its memory status, combined with the analysis of the average occupied memory size of local networks. It also analyzes the current data change trends of local networks to forecast and actively adjust the sending rate of the node in the next period. In order to ensure the fairness and timeliness of the network, the IEEE 802.11 protocol is revised based on waiting time, the number of the node‟s neighbors and the original priority of data packets, which dynamically adjusts the sending priority of the node. The performance of CL-APCC, which is evaluated by extensive simulation experiments. is more efficient in solving the congestion in WSNs. Furthermore, it is clear that the proposed scheme has an outstanding advantage in terms of improving the fairness and lifetime of networks.

  14. Iliotibial band syndrome: evaluation and management.

    Science.gov (United States)

    Strauss, Eric J; Kim, Suezie; Calcei, Jacob G; Park, Daniel

    2011-12-01

    Iliotibial band syndrome is a common overuse injury typically seen in runners, cyclists, and military recruits. Affected patients report lateral knee pain associated with repetitive motion activities. The diagnosis is usually made based on a characteristic history and physical examination, with imaging studies reserved for cases of recalcitrant disease to rule out other pathologic entities. Several etiologies have been proposed for iliotibial band syndrome, including friction of the iliotibial band against the lateral femoral epicondyle, compression of the fat and connective tissue deep to the iliotibial band, and chronic inflammation of the iliotibial band bursa. The mainstay of treatment is nonsurgical; however, in persistent or chronic cases, surgical management is indicated.

  15. HRCT: hop-by-hop rate control technique for congestion control in wireless sensor network

    Science.gov (United States)

    Chakravarthi, Rekha; Cidambaram, Gomathy

    2011-12-01

    In Wireless Sensor Networks, congestion occurs when the traffic rate is high. This happens when the an event is detected in a network. Congestion causes packet loss thus degrading the performance of the network. Hence it necessitates to develop an effective congestion control technique. This paper focuses on congestion due to concurrent transmission. We have proposed an efficient protocol to detect and control congestion in a MAC. The occurrence of congestion is detected by calculating a new metrics called congestion scale. When the congestion scale exceeds the threshold value it intimates, that, congestion has occurred. Congestion notification signal is send to all the nodes. On receiving the notification signal all nodes adjust their transmission rate to control congestion. We have implemented Hop-by-Hop Rate Control Technique(HRCT) to control congestion and to guarantee both high throughput and minimum delay. This technique is implemented successfully in NS-2 simulator. Finally, simulation results have demonstrated the effectiveness of our proposed algorithm.

  16. Question of road traffic congestion and de-congestion in the Greater Johannesburg area: some perspectives

    CSIR Research Space (South Africa)

    Chakwizira, J

    2007-07-01

    Full Text Available . It encouraged car-pooling, flexi time and transportation for staff working over time, in an attempt to create alternative approaches to commuting patterns that help optimize transport time and density. Midtrain and Eskom (the largest electric utility) have... highlights the potential role and scope of telematics in resolving traffic congestion and decongestion within the GJA and the transportation field generally. 3.4 Short term interpolations and simulations 3.4.1 Car pooling and introduction...

  17. The related congestion failure estimating methodology and model in transportation networks

    Science.gov (United States)

    Yuan, PengCheng; Juan, ZhiCai

    2013-10-01

    Previous works about the probability-based transportation networks evaluation method mainly focus on the static reliability evaluation, they ascribe the stochastic of the travel time to the external long time factors (the traffic supply or the traffic demand). Under this situation, the link’s travel time related relationship can be inferred, and it is efficacious for planners or engineers to make a decision for a long time. Even though some evaluation methodologies about transportation networks’ real-time travel time reliability has been presented, these works assume that the link’s travel time is independent. In this paper we relax this assumption. Using the Gauss copula theory, we present a new method to evaluate the transportation networks’ real-time travel time reliability. The results show that it will overestimate the route or the networks’ travel time reliability when not considering the links’ travel time are related. Not only that, we deep the static reliability evaluation model to the dynamic, we also present the link and transportation network congestion failure evaluation model. Estimations from the model are compared to field-measured data. It shows that, under the error interval ±2 times, the link congestion failure model accuracy rate is above 90.3%, under the error interval ±0.05; the net congestion failure model accuracy rate is above 95%.

  18. Stem Cell Therapy for Congestive Heart Failure

    Directory of Open Access Journals (Sweden)

    Gunduz E

    2011-01-01

    Full Text Available IntroductionHeart failure is a major cardiovascular health problem. Coronary artery disease is the leading cause of congestive heart failure (CHF [1]. Cardiac transplantation remains the most effective long-term treatment option, however is limited primarily by donor availability, rejection and infections. Mechanical circulatory support has its own indications and limitations [2]. Therefore, there is a need to develop more effective therapeutic strategies.Recently, regenerative medicine has received considerable scientific attention in the cardiovascular arena. We report here our experience demonstrating the beneficial effects of cardiac stem cell therapy on left ventricular functions in a patient with Hodgkin’s lymphoma (HL who developed CHF due to ischemic heart disease during the course of lymphoma treatment. Case reportA 58-year-old male with relapsed HL was referred to our bone marrow transplantation unit in October 2009. He was given 8 courses of combination chemotherapy with doxorubicin, bleomycin, vincristine, and dacarbazine (ABVD between June 2008 and February 2009 and achieved complete remission. However, his disease relapsed 3 months after completing the last cycle of ABVD and he was decided to be treated with DHAP (cisplatin, cytarabine, dexamethasone followed autologous stem cell transplantation (SCT. After the completion of first course of DHAP regimen, he developed acute myocardial infarction (AMI and coronary artery bypass grafting (CABG was performed. After his cardiac function stabilized, 3 additional courses of DHAP were given and he was referred to our centre for consideration of autologous SCT. Computed tomography scans obtained after chemotherapy confirmed complete remission. Stem cells were collected from peripheral blood after mobilization with 10 µg/kg/day granulocyte colony-stimulating factor (G-CSF subcutaneously. Collection was started on the fifth day of G-CSF and performed for 3 consecutive days. Flow cytometric

  19. Evaluation and Management of Opioid Dependence in Pregnancy

    Science.gov (United States)

    Park, Eliza M; Meltzer-Brody, Samantha; Suzuki, Joji

    2017-01-01

    Background Opioid use disorders are a growing public health problem in the United States. Most women who are opioid dependent are of childbearing age and management of opioid dependence during pregnancy poses unique challenges. Assessment includes evaluation for addiction, withdrawal syndromes, and co-morbid psychiatric diagnoses. Consultation-liaison psychiatrists may also be involved in acute pain management, perinatal medication management, buprenorphine induction and stabilization. For the past four decades, the standard of care has included methadone maintenance, but the increasing use of buprenorphine creates new treatment issues and opportunities. Objective To educate consultation-liaison psychiatrists in emergency and obstetrical settings about the appropriate approach toward the evaluation and basic management of women with opioid dependence in pregnancy. Method The authors reviewed the consensus literature and all new treatment options on opioid dependence during pregnancy. Discussion In this review, the authors summarize known and emerging management strategies for opioid dependence in pregnancy pertinent to consultation-liaison psychiatrists. PMID:22902085

  20. Impact of Consultation on Hospital Outcomes and Resource Utilization for Patients with Acute Congestive Heart Failure.

    Science.gov (United States)

    Varga, Zoltan; Sabzwari, Syed Ali Rafay; Abusaada, Khalid

    2017-07-01

    Consultation is an important tool for acquiring subspecialty support when managing patients with acute congestive heart failure (CHF). The effect of consultation on hospital outcomes and resource utilization in CHF is unknown. The objectives of our study were to determine the effect of consultation on outcomes in CHF and to evaluate factors affecting the frequency of consultation. Our study was a retrospective cohort study of patients admitted to Florida Hospital Orlando for CHF between January 1, 2011 and December 31, 2013. Data on demographics, number of consultations, length of stay (LOS), readmissions within 30 days, cost of care, and mortality were compared according to the number of consultations. For statistical analysis, analysis of variance, the χ(2) test, and multivariate linear regression analysis were used. Risk-adjusted outcomes were reported as observed/expected. A total of 1554 patients were included; 103 (6.6%) patients received no consultation; 482 (31%) received 1; 365 (23.5%) received 2; 229 (14%) received 3; and 375 (24%) received ≥4. Teaching service, age, and African American race were associated with decreased consultation (P consultation (P consultations (P consultations (P = 0.35 and 0.98, respectively). Increased consultation with patients with CHF is associated with increased costs and LOS without improved mortality or readmission rate. Decreased utilization of consultations by the teaching service suggests that there is an opportunity to decrease utilization of healthcare resources by streamlining the utilization of consultations.

  1. Eagle syndrome; radiological evaluation and management.

    Science.gov (United States)

    Kamal, Ahmed; Nazir, Rashed; Usman, Muhammad; Salam, Badar-us-; Sana, Farah

    2014-11-01

    Eagle syndrome is a rare condition where elongated temporal styloid processes, or calcified stylohyoid ligaments, are in conflict with the adjacent anatomical structures giving rise to a complex range of symptoms including otalgia, dysphagia, foreign body sensation in throat, pain along carotid artery distribution and others. Commonly, the syndrome is documented to be unilateral. However, bilateral cases are also reported though rarely. Multislice computed tomography scan with 3D reconstruction can be really helpful in diagnosing the elongated styloid processes and their mass effect on the surrounding adjacent anatomical structures. Scan is also helpful in deciding further management and guides the surgeon on how and from where to approach the surgery. We present here a case of a 37-years-old man with significantly enlarged and thickened bilateral styloid process causing significant characteristic symptoms.

  2. Evaluation and Management of Proximal Humerus Fractures

    Directory of Open Access Journals (Sweden)

    Ekaterina Khmelnitskaya

    2012-01-01

    Full Text Available Proximal humerus fractures are common injuries, especially among older osteoporotic women. Restoration of function requires a thorough understanding of the neurovascular, musculotendinous, and bony anatomy. This paper addresses the relevant anatomy and highlights various management options, including indication for arthroplasty. In the vast majority of cases, proximal humerus fractures may be treated nonoperatively. In the case of displaced fractures, when surgical intervention may be pursued, numerous constructs have been investigated. Of these, the proximal humerus locking plate is the most widely used. Arthroplasty is generally reserved for comminuted 4-part fractures, head-split fractures, or fractures with significant underlying arthritic changes. Reverse total shoulder arthroplasty is reserved for patients with a deficient rotator cuff, or highly comminuted tuberosities.

  3. [Evaluation and management of enuresis. An update].

    Science.gov (United States)

    Riccabona, M

    2010-07-01

    Enuresis is defined as nocturnal bed wetting for at least 2 nights per month in children older than 5 years. At this age the prevalence of enuresis is about 15-20%. More than 50% of these children show day time symptoms, such as frequency, urgency and incontinence (non-monosymptomatic enuresis). The other children are asymptomatic during day time and wet the bed during the night time (monosymptomatic enuresis). The main pathogenetic factors are nycturia, detrusor overactivity and reduced arousability. Psychological and psychiatric aspects, genetics and obstipation play an additional role in the etiology. Basic diagnostic investigations are mandatory before treatment. Clinical history, physical examination, sonography of the urinary tract, urinalysis and bladder diary are prerequisites before any therapeutic steps are taken. The cornerstones of primary enuresis therapy are general lifestyle advice, pharmacotherapy and alarm devices. Therapy-resistant children deserve further evaluation and a multidisciplinary therapy approach. After careful evaluation specific therapy is efficient in approximately 80% of patients.

  4. Evaluating Academic Journals without Impact Factors for Collection Management Decisions.

    Science.gov (United States)

    Dilevko, Juris; Atkinson, Esther

    2002-01-01

    Discussion of evaluating academic journals for collection management decisions focuses on a methodological framework for evaluating journals not ranked by impact factors in Journal Citation Reports. Compares nonranked journals with ranked journals and then applies this framework to a case study in the field of medical science. (LRW)

  5. Considerations in designing an evaluation system for adaptive delta management

    NARCIS (Netherlands)

    Hermans, L.M.; Maat, J.; Haasnoot, M.; Kwakkel, J.H.

    2014-01-01

    New planning approaches put new requirements on evaluation. A recent innovation in the water domain is adaptive delta management (ADM). ADM supports long-term planning in the face of uncertainty. This paper discusses the main considerations for the design of an evaluation system for ADM, departing f

  6. Economic evaluation of enhanced asthma management: a systematic review

    Directory of Open Access Journals (Sweden)

    Yong YV

    2014-12-01

    Full Text Available Objectives: To evaluate and compare full economic evaluation studies on the cost-effectiveness of enhanced asthma management (either as an adjunct to usual care or alone vs. usual care alone. Methods: Online databases were searched for published journal articles in English language from year 1990 to 2012, using the search terms ‘“asthma” AND (“intervene” OR “manage” AND (“pharmacoeconomics” OR “economic evaluation” OR “cost effectiveness” OR “cost benefit” OR “cost utility”’. Hand search was done for local publishing. Only studies with full economic evaluation on enhanced management were included (cost consequences (CC, cost effectiveness (CE, cost benefit (CB, or cost utility (CU analysis. Data were extracted and assessed for the quality of its economic evaluation design and evidence sources. Results: A total of 49 studies were included. There were 3 types of intervention for enhanced asthma management: education, environmental control, and self-management. The most cost-effective enhanced management was a mixture of education and self-management by an integrated team of healthcare and allied healthcare professionals. In general, the studies had a fair quality of economic evaluation with a mean QHES score of 73.7 (SD=9.7, and had good quality of evidence sources. Conclusion: Despite the overall fair quality of economic evaluations but good quality of evidence sources for all data components, this review showed that the delivered enhanced asthma managements, whether as single or mixed modes, were overall effective and cost-reducing. Whilst the availability and accessibility are an equally important factor to consider, the sustainability of the cost-effective management has to be further investigated using a longer time horizon especially for chronic diseases such as asthma.

  7. Evaluation of wholesale electric power market rules and financial risk management by agent-based simulations

    Science.gov (United States)

    Yu, Nanpeng

    As U.S. regional electricity markets continue to refine their market structures, designs and rules of operation in various ways, two critical issues are emerging. First, although much experience has been gained and costly and valuable lessons have been learned, there is still a lack of a systematic platform for evaluation of the impact of a new market design from both engineering and economic points of view. Second, the transition from a monopoly paradigm characterized by a guaranteed rate of return to a competitive market created various unfamiliar financial risks for various market participants, especially for the Investor Owned Utilities (IOUs) and Independent Power Producers (IPPs). This dissertation uses agent-based simulation methods to tackle the market rules evaluation and financial risk management problems. The California energy crisis in 2000-01 showed what could happen to an electricity market if it did not go through a comprehensive and rigorous testing before its implementation. Due to the complexity of the market structure, strategic interaction between the participants, and the underlying physics, it is difficult to fully evaluate the implications of potential changes to market rules. This dissertation presents a flexible and integrative method to assess market designs through agent-based simulations. Realistic simulation scenarios on a 225-bus system are constructed for evaluation of the proposed PJM-like market power mitigation rules of the California electricity market. Simulation results show that in the absence of market power mitigation, generation company (GenCo) agents facilitated by Q-learning are able to exploit the market flaws and make significantly higher profits relative to the competitive benchmark. The incorporation of PJM-like local market power mitigation rules is shown to be effective in suppressing the exercise of market power. The importance of financial risk management is exemplified by the recent financial crisis. In this

  8. Pipeline integrity handbook risk management and evaluation

    CERN Document Server

    Singh, Ramesh

    2013-01-01

    Based on over 40 years of experience in the field, Ramesh Singh goes beyond corrosion control, providing techniques for addressing present and future integrity issues. Pipeline Integrity Handbook provides pipeline engineers with the tools to evaluate and inspect pipelines, safeguard the life cycle of their pipeline asset and ensure that they are optimizing delivery and capability. Presented in easy-to-use, step-by-step order, Pipeline Integrity Handbook is a quick reference for day-to-day use in identifying key pipeline degradation mechanisms and threats to pipeline integrity. The book begins

  9. Pressure ulcers management: an economic evaluation.

    Science.gov (United States)

    Foglia, E; Restelli, U; Napoletano, A M; Coclite, D; Porazzi, E; Bonfanti, M; Croce, D

    2012-03-01

    Pressure ulcer management represents a growing problem for medical and social health care systems all over the world, particularly in European Union countries where the incidence of pressure ulcers in older persons (> 60 years of age) is predicted to rise. The aim of this study was to provide evidence for the lower impact on economic resources of using advanced dressings for the treatment of pressure ulcers with respect to conventional simple dressings. Two different models of analysis, derived from Activity Based Costing and Health Technology Assessment, were used to measure, over a 30-day period, the direct costs incurred by pressure ulcer treatment for community-residing patients receiving integrated home care. Although the mean cost per home care visit was higher in the advanced dressings patient group than in the simple dressings patient one (E 22.31 versus E 16.03), analysis of the data revealed that the cost of using advanced dressings was lower due to fewer home care visits (22 versus 11). The results underline the fact that decision-makers need to improve their understanding of the advantages of taking a long-term view with regards to the purchase and use of materials. This could produce considerable savings of resources in addition to improving treatment efficacy for the benefit of patients and the health care system.

  10. Measuring nurse managers' boundary spanning: development and psychometric evaluation.

    Science.gov (United States)

    Onishi, Mami

    2016-05-01

    To test the psychometric properties of a boundary spanning measure by nurse managers. The health-care environment requires hospital units to coordinate efforts autonomously across their boundaries and to manage relationships with other professionals, units and departments. Boundary spanning has become increasingly important for first-line nurse managers as unit gatekeepers; however, the available measures are limited. The 30-item instrument was developed from a literature review. Survey participants were 4918 nurses at 231 hospital units. Statistical analyses of construct validity and internal consistency were performed. Furthermore, the correlation between nurses' scores on the Nurse Managers Boundary Spanning Scale and nurses' evaluations of their managers were examined. Three factors and 26 items were derived from factor analyses: connecting and mediating, informing and feedback utilisation, and resource acquisition. Cronbach's subscales' alpha coefficients were above 0.9. Correlation analysis indicated that the Nurse Managers Boundary Spanning Scale score correlated with nurses' positive perceptions of their managers. This study demonstrates tentative support for the validity and reliability of the Nurse Managers Boundary Spanning Scale. Although further study is needed, the Nurse Managers Boundary Spanning Scale shows possibilities as a new measurement of nursing leadership. This study underscores measures to build on nurse managers' roles by building on the limited research available. © 2016 John Wiley & Sons Ltd.

  11. The evaluation and management of hirsutism.

    Science.gov (United States)

    Azziz, Ricardo

    2003-05-01

    Hirsutism is the presence of terminal (coarse) hairs in females in a male-like pattern, affecting between 5% and 15% of women, depending on definition. Hirsutism has a significant negative impact on psychosocial development and is usually a sign of an underlying endocrine abnormality-namely, androgen excess. The most common cause of androgen excess is the polycystic ovary syndrome (PCOS), with 21-hydroxylase-deficient nonclassic adrenal hyperplasia, the hyperandrogenic insulin-resistant acanthosis nigricans syndrome, androgen-secreting tumors, and androgenic drug intake occurring less frequently. However, although 70-80% of patients with androgen excess demonstrate hirsutism, this sign may be less prevalent among women of Asian extraction. Conversely, not all hirsute patients have evidence of detectable androgen excess, as 5-15% of these women have "idiopathic hirsutism," with normal ovulatory function and androgen levels. There is a strong familial predilection for hirsutism, primarily because the underlying endocrine disorders (eg, PCOS) and the factors regulating the development of hair growth (eg, androgen receptor activity, 5alpha-reductase activity) have a strong genetic component. The diagnostic evaluation of the potentially hirsute patient first involves confirming the presence of hirsutism and then excluding associated or etiological abnormalities and disorders (eg, ovulatory dysfunction, adrenal hyperplasia, diabetes, thyroid hormone abnormalities). Treatment should be undertaken using combination therapy, to possibly include 1) hormonal suppression (oral contraceptives, long-acting gonadotropin-releasing hormone analogues, and insulin sensitizers), 2) peripheral androgen blockade (spironolactone, flutamide, cyproterone acetate, or finasteride), and 3) mechanical/cosmetic amelioration and destruction of the unwanted hairs (electrology and, potentially, laser hair removal). The application of eflornithine hydrochloride 13.9% topical cream may also be

  12. Enhancing congestion control to address link failure loss over mobile ad-hoc network

    CERN Document Server

    Fard, Mohammad Amin Kheirandish; Aflaki, Mohammad

    2011-01-01

    Standard congestion control cannot detect link failure losses which occur due to mobility and power scarcity in multi-hop Ad-Hoc network (MANET). Moreover, successive executions of Back-off algorithm deficiently grow Retransmission Timeout (RTO) exponentially for new route. The importance of detecting and responding link failure losses is to prevent sender from remaining idle unnecessarily and manage number of packet retransmission overhead. In contrast to Cross-layer approaches which require feedback information from lower layers, this paper operates purely in Transport layer. This paper explores an end-to-end threshold-based algorithm which enhances congestion control to address link failure loss in MANET. It consists of two phases. First, threshold-based loss classification algorithm distinguishes losses due to link failure by estimating queue usage based on Relative One-way Trip Time (ROTT). Second phase adjusts RTO for new route by comparing capabilities of new route to the broken route using available i...

  13. Technical Evaluation Report 30: Vendor-Assisted Evaluation of a Learning Management System

    Directory of Open Access Journals (Sweden)

    Adrienne De Schutter

    2004-04-01

    Full Text Available A product evaluation was conducted of Desire2Learn, an online learning management system gaining popularity in educational institutions. Since an online trial version of the software was not available for evaluation, an inspection meeting with the vendor was arranged. This provided the evaluation team with an opportunity to examine the precautions necessary for ensuring the objectivity of a product evaluation based on vendor-supplied information. The report outlines the team’s use of evaluator-driven enquiry and a triangulated approach to information checking. The Desire2Learn product is assessed as a flexible and useful addition to the range of learning management system options.

  14. Evaluation and management of spinal epidural abscess.

    Science.gov (United States)

    DeFroda, Steven F; DePasse, J Mason; Eltorai, Adam E M; Daniels, Alan H; Palumbo, Mark A

    2016-02-01

    Spinal epidural abscess (SEA) is an uncommon and potentially catastrophic condition. SEA often presents a diagnostic challenge, as the "classic triad" of fever, spinal pain, and neurological deficit is evident in only a minority of patients. When diagnosis is delayed, irreversible neurological damage may ensue. To minimize morbidity, an appropriate level of suspicion and an understanding of the diagnostic evaluation are essential. Infection should be suspected in patients presenting with axial pain, fever, or elevated inflammatory markers. Although patients with no known risk factors can develop SEA, clinical concern should be heightened in the presence of diabetes, intravenous drug use, chronic renal failure, immunosuppressant therapy, or a recent invasive spine procedure. When the clinical profile is consistent with the diagnosis of SEA, gadolinium-enhanced magnetic resonance imaging of the spinal column should be obtained on an emergent basis to delineate the location and neural compressive effect of the abscess. Rapid diagnosis allows for efficient treatment, which optimizes the potential for a positive outcome.

  15. DOE methods for evaluating environmental and waste management samples.

    Energy Technology Data Exchange (ETDEWEB)

    Goheen, S C; McCulloch, M; Thomas, B L; Riley, R G; Sklarew, D S; Mong, G M; Fadeff, S K [eds.; Pacific Northwest Lab., Richland, WA (United States)

    1994-04-01

    DOE Methods for Evaluating Environmental and Waste Management Samples (DOE Methods) provides applicable methods in use by. the US Department of Energy (DOE) laboratories for sampling and analyzing constituents of waste and environmental samples. The development of DOE Methods is supported by the Laboratory Management Division (LMD) of the DOE. This document contains chapters and methods that are proposed for use in evaluating components of DOE environmental and waste management samples. DOE Methods is a resource intended to support sampling and analytical activities that will aid in defining the type and breadth of contamination and thus determine the extent of environmental restoration or waste management actions needed, as defined by the DOE, the US Environmental Protection Agency (EPA), or others.

  16. Controlling the consumption of customers via dynamic pricing and concept for network congestion management in the E-Energy project ''MeRegio''; Steuerung des Kundenverbrauchs mit Hilfe von dynamischen Tarifen und Konzept zur Engpassbeseitigung im E-Energy-Projekt ''MeRegio''

    Energy Technology Data Exchange (ETDEWEB)

    Papasjan, Frank; Backes, Juergen [EnBW Regional AG, Stuttgart (Germany); Kroepelin, Joern [EnBW Vertrieb GmbH, Stuttgart (Germany)

    2011-07-01

    The massive growth of volatile and partially distributed generation as it is requested for achieving the EU climate targets and the environmental concept of the German Federal Government means a big challenge for the future roles of sale, trade, transmission system operators and distribution system operators. The involved parties agree that in future a smart grid will be needed for providing for a stable system operation along with affordable cost for storage systems and network expansion. It is not clear however what the smart grid really will be composed of. In Germany the publicly funded programme ''E-Energy'' is driving 6 projects running between 2009 and 2012 and implementing different visions of a smart energy system. First results are available now - amongst others also from the project MeRegio which is in the focus of this report. The first part of the paper discusses the flexibility of consumption as observed among the thousand pioneer customers. It evaluates how sustainable the adaptions of the consumption to the dynamic tariffs and thus to the production based on renewable resources are. The second part of this paper deals with the concept designed to mitigate future grid congestions by economic incentives placed to a customer flexibility market for both generation and load. (orig.)

  17. Building an Evaluative Culture: The Key to Effective Evaluation and Results Management

    Science.gov (United States)

    Mayne, John

    2009-01-01

    As many reviews of results-based performance systems have noted, a weak evaluative culture in an organization undermines attempts at building an effective evaluation and/or results management regime. This article sets out what constitutes a strong evaluative culture where information on performance results is deliberately sought in order to learn…

  18. Evaluating the Readiness of Iranian Research Centers in Knowledge Management

    Directory of Open Access Journals (Sweden)

    Nasrin D. Mamaghani

    2011-01-01

    Full Text Available Problem statement: Knowledge and its management are considered as a foundation for creating competitive advantages in organizations. Most of large companies have allocated plenty of resources to Knowledge Management (KM because they believe Knowledge and its management is a foundation for creating competitive advantages in organizations. However, implementing knowledge management projects in an organization requires essential organizational changes. The main purpose of this study was to explore KM success factors of Iranian research center to make a basis for evaluating the readiness of KM in them. Approach: In this study, success factors of knowledge management were extracted from literature review on papers represented between 1997 and 2009. Then the factors were categorized and effective and critical success factors in each group were determined. The results were validated and analyzed by a questionnaire through binomial test and approved by an expert panel. Results: The study revealed that KM success factors of Iranian research centers are: Knowledge strategy, management support, motivational encouragements to share knowledge, suitable technical infrastructure. It is obvious that continuous attention of management to these factors is vital for the success of knowledge management in organizations. Conclusions: Based on results, to improve current situation of KM in Iranian research center, KM and its benefits should be represented to managers to attract their support in organization. Then KM should be employed in strategic program of organization. Besides, implementing the projects of KM should be accompanied with reward and motivational systems to facilitate knowledge sharing and create proper organizational culture.

  19. Cell therapy in congestive heart failure

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Congestive heart failure (CHF) has emerged as a major worldwide epidemic and its main causes seem to be the aging of the population and the survival of patients with post-myocardial infarction. Cardiomyocyte dropout (necrosis and apoptosis) plays a critical role in the progress of CHF; thus treatment of CHF by exogenous cell implantation will be a promising medical approach. In the acute phase of cardiac damage cardiac stem cells (CSCs) within the heart divide symmetrically and/or asymmetrically in response to the change of heart homeostasis, and at the same time homing of bone marrow stem cells (BMCs) to injured area is thought to occur, which not only reconstitutes CSC population to normal levels but also repairs the heart by differentiation into cardiac tissue. So far, basic studies by using potential sources such as BMCs and CSCs to treat animal CHF have shown improved ventricular remodelling and heart function. Recently, however, a few of randomized, double-blind, placebo-controlled clinical trials demonstrated mixed results in heart failure with BMC therapy during acute myocardial infarction.

  20. Research on Prediction of Traffic Congestion State

    Directory of Open Access Journals (Sweden)

    Zhao Jun

    2015-01-01

    Full Text Available This method of prediction using the data mining to analyze huge amounts of data as a preferred tool has been widely used in various fields. In the midst of it, the routine traffic data exists in a large number of isolated data in real time without establishing relationships with other data, and detects the amount of data which is greater than that at present. The usage of these data which is relatively shallow requires an in-depth analysis of its data model. Therefore, this paper uses a fuzzy clustering analysis method of feature points to study the traffic flow, uses a Markov decision chain model to study traffic jams, uses quantitative sample points based on the information entropy to calculate traffic flow trends and uses a heuristic prediction model to predict the road con-gestion. Through the simulation experiment which verifies the correctness of the model, this research is to advance the development of the road and to provide a basis for a dredging plan.

  1. Re-Thinking the TCP Congestion Control Design in Network Simulators

    OpenAIRE

    Hume, Allison

    2016-01-01

    In contrast to live hardware testbeds, which are evaluated largely on performance, network simulators are primarily used to test and validate new protocols and algorithms. As such, a network simulator should be designed to be modular, extensible, re-usable, and robust. This work examines the design of TCP congestion control in the ns-3 network simulator and presents a new design, not specific to ns-3, that will be more modular and extensible. We also demonstrate that the implementation in the...

  2. The impact of the congestion charging scheme on air quality in London. Part 1. Emissions modeling and analysis of air pollution measurements.

    Science.gov (United States)

    Kelly, Frank; Anderson, H Ross; Armstrong, Ben; Atkinson, Richard; Barratt, Ben; Beevers, Sean; Derwent, Dick; Green, David; Mudway, Ian; Wilkinson, Paul

    2011-04-01

    On February 17, 2003, a congestion charging scheme (CCS*) was introduced in central London along with a program of traffic management measures. The scheme operated Monday through Friday, 7 AM to 6 PM. This program resulted in an 18% reduction in traffic volume and a 30% reduction in traffic congestion in the first year (2003). We developed methods to evaluate the possible effects of the scheme on air quality: We used a temporal-spatial design in which modeled and measured air quality data from roadside and background monitoring stations were used to compare time periods before (2001-2002) and after (2003-2004) the CCS was introduced and to compare the spatial area of the congestion charging zone (CCZ) with the rest of London. In the first part of this project, we modeled changes in concentrations of oxides of nitrogen (NOx), nitrogen dioxide (NO2), and PM10 (particles with a mass median aerodynamic diameter advantages and limitations. The placement of monitoring sites and the availably of traffic count data were also identified as key issues. The most compelling lesson we take away from this study is that such work is impossible to undertake without a coherent multi-disciplinary team of skilled researchers. In conclusion, our study suggests that the introduction of the CCS in 2003 was associated with small temporal changes in air pollutant concentrations in central London compared with outer areas. However, attributing the cause of these changes to the CCS alone is not appropriate because the scheme was introduced at a time when other traffic and emissions interventions, which might have had a more concentrated effect in central London, were also being implemented.

  3. Evaluation of Workflow Management Systems - A Meta Model Approach

    Directory of Open Access Journals (Sweden)

    Michael Rosemann

    1998-11-01

    Full Text Available The automated enactment of processes through the use of workflow management systems enables the outsourcing of the control flow from application systems. By now a large number of systems, that follow different workflow paradigms, are available. This leads to the problem of selecting the appropriate workflow management system for a given situation. In this paper we outline the benefits of a meta model approach for the evaluation and comparison of different workflow management systems. After a general introduction on the topic of meta modeling the meta models of the workflow management systems WorkParty (Siemens Nixdorf and FlowMark (IBM are compared as an example. These product specific meta models can be generalized to meta reference models, which helps to specify a workflow methodology. Exemplary, an organisational reference meta model is presented, which helps users in specifying their requirements for a workflow management system.

  4. Management effectiveness evaluation in protected areas of southern Ecuador.

    Science.gov (United States)

    López-Rodríguez, Fausto; Rosado, Daniel

    2017-04-01

    Protected areas are home to biodiversity, habitats and ecosystem as well as a critical component of human well-being and a generator of leisure-related revenues. However, management is sometimes unsatisfactory and requires new ways of evaluation. Management effectiveness of 36 protected areas in southern Ecuador have been assessed. The protected areas belong to three categories: Heritage of Natural Areas of the Ecuadorian State (PANE), created and funded by the State, Areas of Forest and Protective Vegetation (ABVP), created but no funded by the State, and private reserves, declared and funded by private entities. Management effectiveness was evaluated by answers of managers of the protected areas to questionnaires adapted to the socio-economic and environmental characteristics of the region. Questions were classified into six elements of evaluation: context, planning, inputs, processes, outputs and outcomes as recommended by IUCN. Results were classified into four levels: unsatisfactory, slightly satisfactory, satisfactory and very satisfactory. The PANE areas and private reserves showed higher management effectiveness levels (satisfactory and very satisfactory) than ABVP areas, where slightly satisfactory and unsatisfactory levels prevailed. Resources availability was found as the main reason behind this difference. The extension, age and province of location were found irrelevant. Outputs, inputs and processes require main efforts to improve management effectiveness. Improving planning and input in the PANE areas and inputs and outcomes on ABVP areas is necessary to obtain a similar result in all areas.

  5. Comparison of Active Queue Management Congestion Control Algorithms Based on NS%基于ns的主动队列管理拥塞控制算法的比较

    Institute of Scientific and Technical Information of China (English)

    赵雪梅; 牛秦洲; 侯辉

    2008-01-01

    主动式队列管理(Active Queue Management, AQM)技术是IETF(The Internet Engineering Task Force)为了解决Internet拥塞控制问题而提出的一种路由器缓存管理技术.本文详细分析了RED算法、BLUE算法以及基于RED改进策略的SRED算法三种算法的优缺点,并在NS2中对它们的性能进行了仿真和比较.仿真结果表明RED和SRED性能都要优于BLUE算法.

  6. Application of a theoretical model to evaluate COPD disease management

    Directory of Open Access Journals (Sweden)

    Asin Javier D

    2010-03-01

    Full Text Available Abstract Background Disease management programmes are heterogeneous in nature and often lack a theoretical basis. An evaluation model has been developed in which theoretically driven inquiries link disease management interventions to outcomes. The aim of this study is to methodically evaluate the impact of a disease management programme for patients with chronic obstructive pulmonary disease (COPD on process, intermediate and final outcomes of care in a general practice setting. Methods A quasi-experimental research was performed with 12-months follow-up of 189 COPD patients in primary care in the Netherlands. The programme included patient education, protocolised assessment and treatment of COPD, structural follow-up and coordination by practice nurses at 3, 6 and 12 months. Data on intermediate outcomes (knowledge, psychosocial mediators, self-efficacy and behaviour and final outcomes (dyspnoea, quality of life, measured by the CRQ and CCQ, and patient experiences were obtained from questionnaires and electronic registries. Results Implementation of the programme was associated with significant improvements in dyspnoea (p Conclusions The application of a theory-driven model enhances the design and evaluation of disease management programmes aimed at improving health outcomes. This study supports the notion that a theoretical approach strengthens the evaluation designs of complex interventions. Moreover, it provides prudent evidence that the implementation of COPD disease management programmes can positively influence outcomes of care.

  7. Application of a theoretical model to evaluate COPD disease management.

    Science.gov (United States)

    Lemmens, Karin M M; Nieboer, Anna P; Rutten-Van Mölken, Maureen P M H; van Schayck, Constant P; Asin, Javier D; Dirven, Jos A M; Huijsman, Robbert

    2010-03-26

    Disease management programmes are heterogeneous in nature and often lack a theoretical basis. An evaluation model has been developed in which theoretically driven inquiries link disease management interventions to outcomes. The aim of this study is to methodically evaluate the impact of a disease management programme for patients with chronic obstructive pulmonary disease (COPD) on process, intermediate and final outcomes of care in a general practice setting. A quasi-experimental research was performed with 12-months follow-up of 189 COPD patients in primary care in the Netherlands. The programme included patient education, protocolised assessment and treatment of COPD, structural follow-up and coordination by practice nurses at 3, 6 and 12 months. Data on intermediate outcomes (knowledge, psychosocial mediators, self-efficacy and behaviour) and final outcomes (dyspnoea, quality of life, measured by the CRQ and CCQ, and patient experiences) were obtained from questionnaires and electronic registries. Implementation of the programme was associated with significant improvements in dyspnoea (p model showed associations between significantly improved intermediate outcomes and improvements in quality of life and dyspnoea. The application of a theory-driven model enhances the design and evaluation of disease management programmes aimed at improving health outcomes. This study supports the notion that a theoretical approach strengthens the evaluation designs of complex interventions. Moreover, it provides prudent evidence that the implementation of COPD disease management programmes can positively influence outcomes of care.

  8. Decrease of cardiac chaos in congestive heart failure

    Science.gov (United States)

    Poon, Chi-Sang; Merrill, Christopher K.

    1997-10-01

    The electrical properties of the mammalian heart undergo many complex transitions in normal and diseased states. It has been proposed that the normal heartbeat may display complex nonlinear dynamics, including deterministic chaos,, and that such cardiac chaos may be a useful physiological marker for the diagnosis and management, of certain heart trouble. However, it is not clear whether the heartbeat series of healthy and diseased hearts are chaotic or stochastic, or whether cardiac chaos represents normal or abnormal behaviour. Here we have used a highly sensitive technique, which is robust to random noise, to detect chaos. We analysed the electrocardiograms from a group of healthy subjects and those with severe congestive heart failure (CHF), a clinical condition associated with a high risk of sudden death. The short-term variations of beat-to-beat interval exhibited strongly and consistently chaotic behaviour in all healthy subjects, but were frequently interrupted by periods of seemingly non-chaotic fluctuations in patients with CHF. Chaotic dynamics in the CHF data, even when discernible, exhibited a high degree of random variability over time, suggesting a weaker form of chaos. These findings suggest that cardiac chaos is prevalent in healthy heart, and a decrease in such chaos may be indicative of CHF.

  9. Individual Tradable Permit Market And Traffic Congestion: An Experimental Study

    Directory of Open Access Journals (Sweden)

    Kean Siang Ch’ng

    2012-01-01

    Full Text Available The increasing vehicular traffic and the consequent over-consumption have emerged as the results of rapid motorization and urbanization throughout the world. Variety of measures have been attempted to deal with the vehicular problems. This paper was intended to investigate the potential of an individual tradable permit system in an experimental two-sided repeated double auction market to overcome over-consumption through road demand management. The auction began with the local authority distributing access rights to the vehicular owners. The owners could either use up the permit or to purchase permit from the open market. The latter allowed usage beyond the owner’s quota. The system showed that traders exhibited strong dependence on reservation price and there were significant transfers of permit from low-value users to high-value users: low-value owners sold access rights to high-value owners. Consequently, in the peak hours, the permit price increased owing to high demand, so the cost of using the road was high during congestion. This created incentive for low-value drivers to postpone their trips and resold permits in the peak hours to gain profit. The results showed the delayer pays principle, in which drivers who valued highly had to pay drivers who were willing to stay off the road during peak hours.

  10. Measurement of effective renal plasma flow in congestive heart failure

    Energy Technology Data Exchange (ETDEWEB)

    Tauxe, W.N.; Dubovsky, E.V.; Mantle, J.A.; Dustan, H.P.; Logic, J.R.

    1981-12-01

    In the management of patients with congestive heart failure (CHF), it is often desirable to have precise knowledge of overall renal function, including the effective renal plasma flow (ERPF). It has long been recognized that ERPF is diminished in CHF. Since glomerular filtration rate is often decreased to a much lesser extent, other noninvasive procedures such as the measurement of creatinine clearances may not be entirely suitable. ERPF determination by the single plasma sampling (SPS) method affords a rapid, simple, noninvasive, and economical technique that is quite accurate and reproducible. A SPS method has been well-tested in patients following renal transplantation plus a wide variety of nephrological disorders. We have been concerned whether the SPS method would be valid in volume expanded patients. In 28 determinations of ERPF in patients with CHF, and in five patients who did not have CHF, we have found the SPS estimation of ERPF to yield results that are not clinically significantly different from those obtained by the detailed compartmental analysis method. The volumes of /sup 131/I-orthoiodohippurate (OIH) distribution were found to be somewhat higher in CHF than in controls, but fractional rate constants were proportionately lower so that intercompartmental flow rates and OIH concentrations were not different from controls. Therefore, the SPS estimation of ERPF is valid in patients with CHF and may be useful in monitoring the renal effects of various hemodynamic and pharmacological interventions.

  11. Congested Link Inference Algorithms in Dynamic Routing IP Network

    Directory of Open Access Journals (Sweden)

    Yu Chen

    2017-01-01

    Full Text Available The performance descending of current congested link inference algorithms is obviously in dynamic routing IP network, such as the most classical algorithm CLINK. To overcome this problem, based on the assumptions of Markov property and time homogeneity, we build a kind of Variable Structure Discrete Dynamic Bayesian (VSDDB network simplified model of dynamic routing IP network. Under the simplified VSDDB model, based on the Bayesian Maximum A Posteriori (BMAP and Rest Bayesian Network Model (RBNM, we proposed an Improved CLINK (ICLINK algorithm. Considering the concurrent phenomenon of multiple link congestion usually happens, we also proposed algorithm CLILRS (Congested Link Inference algorithm based on Lagrangian Relaxation Subgradient to infer the set of congested links. We validated our results by the experiments of analogy, simulation, and actual Internet.

  12. Traffic congestion and the lifetime of networks with moving nodes

    Science.gov (United States)

    Yang, Xianxia; Li, Jie; Pu, Cunlai; Yan, Meichen; Sharafat, Rajput Ramiz; Yang, Jian; Gakis, Konstantinos; Pardalos, Panos M.

    2017-01-01

    For many power-limited networks, such as wireless sensor networks and mobile ad hoc networks, maximizing the network lifetime is the first concern in the related designing and maintaining activities. We study the network lifetime from the perspective of network science. In our model, nodes are initially assigned a fixed amount of energy moving in a square area and consume the energy when delivering packets. We obtain four different traffic regimes: no, slow, fast, and absolute congestion regimes, which are basically dependent on the packet generation rate. We derive the network lifetime by considering the specific regime of the traffic flow. We find that traffic congestion inversely affects network lifetime in the sense that high traffic congestion results in short network lifetime. We also discuss the impacts of factors such as communication radius, node moving speed, routing strategy, etc., on network lifetime and traffic congestion.

  13. A global take on congestion in urban areas

    CERN Document Server

    Barthelemy, Marc

    2016-01-01

    We analyze the congestion data collected by a GPS device company (TomTom) for almost 300 urban areas in the world. Using simple scaling arguments and data fitting we show that congestion during peak hours in large cities grows essentially as the square root of the population density. This result, at odds with previous publications showing that gasoline consumption decreases with density, confirms that density is indeed an important determinant of congestion, but also that we need urgently a better theoretical understanding of this phenomena. This incomplete view at the urban level leads thus to the idea that thinking about density by itself could be very misleading in congestion studies, and that it is probably more useful to focus on the spatial redistribution of activities and residences.

  14. Influence of periodic traffic congestion on epidemic spreading

    Science.gov (United States)

    Zheng, Muhua; Ruan, Zhongyuan; Tang, Ming; Do, Younghae; Liu, Zonghua

    2016-11-01

    In the metropolis, traffic congestion has become a very serious problem, especially in rush hours. This congestion causes people to have more chance to contact each other and thus will accelerate epidemic spreading. To explain this observation, we present a reaction-diffusion (RD) model with a periodic varying diffusion rate to represent the daily traveling behaviors of human beings and its influence to epidemic spreading. By extensive numerical simulations, we find that the epidemic spreading can be significantly influenced by traffic congestion where the amplitude, period and duration of diffusion rate are the three key parameters. Furthermore, a brief theory is presented to explain the effects of the three key parameters. These findings suggest that except the normal ways of controlling contagion in working places and long-distance traveling, controlling the contagion in daily traffic congestion may be another effective way to reduce epidemic spreading.

  15. Proposed congestion control method for cloud computing environments

    CERN Document Server

    Kuribayashi, Shin-ichi

    2012-01-01

    As cloud computing services rapidly expand their customer base, it has become important to share cloud resources, so as to provide them economically. In cloud computing services, multiple types of resources, such as processing ability, bandwidth and storage, need to be allocated simultaneously. If there is a surge of requests, a competition will arise between these requests for the use of cloud resources. This leads to the disruption of the service and it is necessary to consider a measure to avoid or relieve congestion of cloud computing environments. This paper proposes a new congestion control method for cloud computing environments which reduces the size of required resource for congested resource type instead of restricting all service requests as in the existing networks. Next, this paper proposes the user service specifications for the proposed congestion control method, and clarifies the algorithm to decide the optimal size of required resource to be reduced, based on the load offered to the system. I...

  16. Algorithm of urban road congestion pricing with game theory%城市道路交通拥挤收费的博弈分析

    Institute of Scientific and Technical Information of China (English)

    朱广芹; 佟光霁; 代磊磊

    2009-01-01

    在分析城市道路交通拥挤收费基本原理的基础上,应用博弈论的分析方法,针对用户之间的出行、管理者和用户之间的拥挤收费进行了博弈分析,探讨了影响道路拥挤收费的因素,设计了基于博弈模型的拥挤收费算法.结果表明:该算法可以给出不同程度拥挤道路收费的数值区间,对道路拥挤收费定价和交通管理有一定的实用价值.%This paper applied game theory method to analyze the relations between travelers and travelers with managers based on the economic analysis of urban road congestion pricing, then discussed the influencing factors of road congestion pricing. An algorithm of congestion pricing was designed based on game theory.The results showed that the algorithm might benefit the road congestion pricing and traffic management because it could compute congestion toll with the extent of road congestion.

  17. Congestion aware forwarding in delay tolerant and social opportunistic networks

    OpenAIRE

    Radenkovic, Milena; Grundy, Andrew

    2011-01-01

    We propose an approach for opportunistic forwarding that supports optimization of multipoint high volume data flow transfer while maintaining high buffer availability and low delays. This paper explores a number of social, buffer and delay heuristics to offload the traffic from congested parts of the network and spread it over less congested parts of the network in order to keep low delays, high success ratios and high availability of nodes. We conduct an extensive set of experiments for asse...

  18. Road Pricing, Traffic Congestion and Economic Welfare: A Note

    OpenAIRE

    Ingo Böbel; Casimir de Rham

    2004-01-01

    Only recently, the subject of road pricing to reduce traffic congestion gained increasing importance in Europe. This paper uses a standard microeconomic approach to show that road user price charging to avoid traffic congestion is optimal from a society’s point of view as it improves economic efficiency of allocating a scarce resource (road space) by reducing the welfare loss (as being measured by a loss in consumer surplus) for everyone in the society.

  19. An evaluation of management strategies for Atlantic tuna stocks

    Directory of Open Access Journals (Sweden)

    L. T. Kell

    2003-04-01

    Full Text Available International agreements for the International Commission for the Conservation of Atlantic Tunas (ICCAT convention area imply that Atlantic tuna stocks should be managed by strategies based on maximum sustainable yield (MSY; however, there is concern whether this will actually ensure sustainability with sufficiently high probability consistent with the principals of the precautionary approach. Therefore, the performance of MSY management strategies based on current assessment procedures was evaluated using a computer simulation framework. The framework includes the data collection, assessment, prediction, and management processes, as well as the implementation of management regulations. It therefore provides an integrated way to evaluate the relative importance of and the interactions between each component of the system with regard to the overall success of the management strategy. The study elucidates guidelines about assessment and management that are general enough to be applied to all tunas in the Atlantic Ocean. It does so by comparing different hypotheses about management and assessment for three stocks (North Atlantic albacore, Atlantic bigeye and East Atlantic skipjack, which are representative of the variety encountered (i.e. from data rich to poor and tropical to temperate waters in ICCAT stocks. Management performance was especially sensitive to the carrying capacity of the stock. The type of proxy used for MSY was more important to the success of the procedure than the frequency of assessment or the number of indices used in the assessment. Whilst the procedure was successful at achieving the management objectives for albacore, it was only partially successful for bigeye and was too conservative for skipjack.

  20. Performance measurement for supply chain management and evaluation criteria determination for reverse supply chain management

    Science.gov (United States)

    Kongar, N. Elif

    2004-12-01

    Today, since customers are able to obtain similar-quality products for similar prices, the lead time has become the only preference criterion for most of the consumers. Therefore, it is crucial that the lead time, i.e., the time spent from the raw material phase till the manufactured good reaches the customer, is minimized. This issue can be investigated under the title of Supply Chain Management (SCM). An efficiently managed supply chain can lead to reduced response time for customers. To achieve this, continuous observation of supply chain efficiency, i.e., a constant performance evaluation of the current SCM is required. Widely used conventional performance measurement methods lack the ability to evaluate a SCM since the supply chain is a dynamic system that requires a more thorough and flexible performance measurement technique. Balanced Scorecard (BS) is an efficient tool for measuring the performance of dynamic systems and has a proven capability of providing the decision makers with the appropriate feedback data. In addition to SCM, a relatively new management field, namely reverse supply chain management (RSCM), also necessitates an appropriate evaluation approach. RSCM differs from SCM in many aspects, i.e., the criteria used for evaluation, the high level of uncertainty involved etc., not allowing the usage of identical evaluation techniques used for SCM. This study proposes a generic Balanced Scorecard to measure the performance of supply chain management while defining the appropriate performance measures for SCM. A scorecard prototype, ESCAPE, is presented to demonstrate the evaluation process.

  1. Local empathy provides global minimization of congestion in communication networks.

    Science.gov (United States)

    Meloni, Sandro; Gómez-Gardeñes, Jesús

    2010-11-01

    We present a mechanism to avoid congestion in complex networks based on a local knowledge of traffic conditions and the ability of routers to self-coordinate their dynamical behavior. In particular, routers make use of local information about traffic conditions to either reject or accept information packets from their neighbors. We show that when nodes are only aware of their own congestion state they self-organize into a hierarchical configuration that delays remarkably the onset of congestion although leading to a sharp first-order-like congestion transition. We also consider the case when nodes are aware of the congestion state of their neighbors. In this case, we show that empathy between nodes is strongly beneficial to the overall performance of the system and it is possible to achieve larger values for the critical load together with a smooth, second-order-like, transition. Finally, we show how local empathy minimize the impact of congestion as much as global minimization. Therefore, here we present an outstanding example of how local dynamical rules can optimize the system's functioning up to the levels reached using global knowledge.

  2. Local Empathy provides Global Minimization of Congestion in Communication Networks

    CERN Document Server

    Meloni, Sandro

    2010-01-01

    We present a novel mechanism to avoid congestion in complex networks based on local knowledge of traffic conditions and the ability of routers to self-coordinate their dynamical behavior. In particular, routers make use of local information about traffic conditions to either reject or accept information packets from their neighbors. We show that when nodes are only aware of their own congestion state they self-organize into a hierarchical configuration that delays remarkably the onset of congestion although, leading to a sharp first-order like congestion transition. We also consider the case when nodes are aware of the congestion state of their neighbors. In this case, we show that empathy between nodes is strongly beneficial to the overall performance of the system and it is possible to achieve larger values for the critical load together with a smooth, second-order like, transition. Finally, we show how local empathy minimize the impact of congestion as much as global minimization. Therefore, here we presen...

  3. Local empathy provides global minimization of congestion in communication networks

    Science.gov (United States)

    Meloni, Sandro; Gómez-Gardeñes, Jesús

    2010-11-01

    We present a mechanism to avoid congestion in complex networks based on a local knowledge of traffic conditions and the ability of routers to self-coordinate their dynamical behavior. In particular, routers make use of local information about traffic conditions to either reject or accept information packets from their neighbors. We show that when nodes are only aware of their own congestion state they self-organize into a hierarchical configuration that delays remarkably the onset of congestion although leading to a sharp first-order-like congestion transition. We also consider the case when nodes are aware of the congestion state of their neighbors. In this case, we show that empathy between nodes is strongly beneficial to the overall performance of the system and it is possible to achieve larger values for the critical load together with a smooth, second-order-like, transition. Finally, we show how local empathy minimize the impact of congestion as much as global minimization. Therefore, here we present an outstanding example of how local dynamical rules can optimize the system’s functioning up to the levels reached using global knowledge.

  4. A theory of traffic congestion at moving bottlenecks

    Science.gov (United States)

    Kerner, Boris S.; Klenov, Sergey L.

    2010-10-01

    The physics of traffic congestion occurring at a moving bottleneck on a multi-lane road is revealed based on the numerical analyses of vehicular traffic with a discrete stochastic traffic flow model in the framework of three-phase traffic theory. We find that there is a critical speed of a moving bottleneck at which traffic breakdown, i.e. a first-order phase transition from free flow to synchronized flow, occurs spontaneously at the moving bottleneck, if the flow rate upstream of the bottleneck is great enough. The greater the flow rate, the higher the critical speed of the moving bottleneck. A diagram of congested traffic patterns at the moving bottleneck is found, which shows regions in the flow-rate-moving-bottleneck-speed plane in which congested patterns emerge spontaneously or can be induced through large enough disturbances in an initial free flow. A comparison of features of traffic breakdown and resulting congested patterns at the moving bottleneck with known ones at an on-ramp (and other motionless) bottleneck is made. Nonlinear features of complex interactions and transformations of congested traffic patterns occurring at on- and off-ramp bottlenecks due to the existence of the moving bottleneck are found. The physics of the phenomenon of traffic congestion due to 'elephant racing' on a multi-lane road is revealed.

  5. Optimal structure of complex networks for minimizing traffic congestion.

    Science.gov (United States)

    Zhao, Liang; Cupertino, Thiago Henrique; Park, Kwangho; Lai, Ying-Cheng; Jin, Xiaogang

    2007-12-01

    To design complex networks to minimize traffic congestion, it is necessary to understand how traffic flow depends on network structure. We study data packet flow on complex networks, where the packet delivery capacity of each node is not fixed. The optimal configuration of capacities to minimize traffic congestion is derived and the critical packet generating rate is determined, below which the network is at a free flow state but above which congestion occurs. Our analysis reveals a direct relation between network topology and traffic flow. Optimal network structure, free of traffic congestion, should have two features: uniform distribution of load over all nodes and small network diameter. This finding is confirmed by numerical simulations. Our analysis also makes it possible to theoretically compare the congestion conditions for different types of complex networks. In particular, we find that network with low critical generating rate is more susceptible to congestion. The comparison has been made on the following complex-network topologies: random, scale-free, and regular.

  6. Traffic flooding the low countries: How the Dutch cope with motorway congestion

    NARCIS (Netherlands)

    Bovy, P.H.L.

    1998-01-01

    The road congestion problem in The Netherlands is addressed. Focus is on congestion development and congestion patterns on the Dutch motonA/ays. In order to understand the nature and extent of motorway congestion a description is given of the special features of the Dutch motorway network. Special a

  7. Nationwide SIP Telephony Network Design to Prevent Congestion Caused by Disaster

    Science.gov (United States)

    Satoh, Daisuke; Ashitagawa, Kyoko

    We present a session initiation protocol (SIP) network design for a voice-over-IP network to prevent congestion caused by people calling friends and family after a disaster. The design increases the capacity of SIP servers in a network by using all of the SIP servers equally. It takes advantage of the fact that equipment for voice data packets is different from equipment for signaling packets in SIP networks. Furthermore, the design achieves simple routing on the basis of telephone numbers. We evaluated the performance of our design in preventing congestion through simulation. We showed that the proposed design has roughly 20 times more capacity, which is 57 times the normal load, than the conventional design if a disaster were to occur in Niigata Prefecture struck by the Chuetsu earthquake in 2004.

  8. Investigation on TCP/IP Congestion Control in Optical Burst Switched (OBS Network

    Directory of Open Access Journals (Sweden)

    Ms. Payal Daryani

    2012-03-01

    Full Text Available Transport Control Protocol (TCP is the dominant protocol in modern communication networks, in which the issues of reliability, flow, and congestion control must be handled efficiently. In this review paper an analytical switching is used to exploit the huge bandwidth of optical fibers for future high speed internet backbone. It carries multiple packets, in their turn. Different aggregation schemes have been considered and evaluated.TCP performance greatly depends on the TCP congestion window behavior that is related to loss events occurring in the optical burst switched network, there is a special term called traffic shaping by which we control over the network according to the network load .that means we increase or decrease the send rate according to the network demand.

  9. Research on traffic congestion mechanism and countermeasures based on dynamic traffic assignment

    Institute of Scientific and Technical Information of China (English)

    PEI Yu-long; LANG Yi-shun

    2005-01-01

    Traffic congestion is widely distributed around a network. Generally, to analyze traffic congestion, static traffic capacity is adopted. But dynamic characteristics must be studied because congestion is a dynamic process. A Dynamic Traffic Assignment modeling fundamental combined with an urban congestion analysis method is studied in this paper. Three methods are based on congestion analysis, and the stochastic user optimal DTA models are especially considered. Correspondingly, a dynamic system optimal model is suggested for responding congestion countermeasures and an ideal user optimal model for predicted congestion countermeasure respectively.

  10. Monitoring road traffic congestion using a macroscopic traffic model and a statistical monitoring scheme

    KAUST Repository

    Zeroual, Abdelhafid

    2017-08-19

    Monitoring vehicle traffic flow plays a central role in enhancing traffic management, transportation safety and cost savings. In this paper, we propose an innovative approach for detection of traffic congestion. Specifically, we combine the flexibility and simplicity of a piecewise switched linear (PWSL) macroscopic traffic model and the greater capacity of the exponentially-weighted moving average (EWMA) monitoring chart. Macroscopic models, which have few, easily calibrated parameters, are employed to describe a free traffic flow at the macroscopic level. Then, we apply the EWMA monitoring chart to the uncorrelated residuals obtained from the constructed PWSL model to detect congested situations. In this strategy, wavelet-based multiscale filtering of data has been used before the application of the EWMA scheme to improve further the robustness of this method to measurement noise and reduce the false alarms due to modeling errors. The performance of the PWSL-EWMA approach is successfully tested on traffic data from the three lane highway portion of the Interstate 210 (I-210) highway of the west of California and the four lane highway portion of the State Route 60 (SR60) highway from the east of California, provided by the Caltrans Performance Measurement System (PeMS). Results show the ability of the PWSL-EWMA approach to monitor vehicle traffic, confirming the promising application of this statistical tool to the supervision of traffic flow congestion.

  11. Highly Dynamic and Adaptive Traffic Congestion Avoidance in Real-Time Inspired by Honey Bee Behavior

    Science.gov (United States)

    Wedde, Horst F.; Lehnhoff, Sebastian; van Bonn, Bernhard; Bay, Z.; Becker, S.; Böttcher, S.; Brunner, C.; Büscher, A.; Fürst, T.; Lazarescu, A. M.; Rotaru, E.; Senge, S.; Steinbach, B.; Yilmaz, F.; Zimmermann, T.

    Traffic congestions have become a major problem in metropolitan areas world-wide, within and between cities, to an extent where they make driving and transportation times largely unpredictable. Due to the highly dynamic character of congestion building and dissolving this phenomenon appears even to resist a formal treatment. Static approaches, and even more their global management, have proven counterproductive in practice. Given the latest progress in VANET technology and the remarkable commercially driven efforts like in the European C2C consortium, or the VSC Project in the US, allow meanwhile to tackle various aspects of traffic regulation through VANET communication. In this paper we introduce a novel, completely decentralized multi-agent routing algorithm (termed BeeJamA) which we have derived from the foraging behavior of honey bees. It is highly dynamic, adaptive, robust, and scalable, and it allows for both avoiding congestions, and minimizing traveling times to individual destinations. Vehicle guidance is provided well ahead of every intersection, depending on the individual speeds. Thus strict deadlines are imposed on, and respected by, the BeeJamA algorithm. We report on extensive simulation experiments which show the superior performance of BeeJamA over conventional approaches.

  12. [Intraoperative fluid therapy in infants with congestive heart failure due to intracranial pial arteriovenous fistula].

    Science.gov (United States)

    Arroyo-Fernández, F J; Calderón-Seoane, E; Rodríguez-Peña, F; Torres-Morera, L M

    2016-05-01

    Pial arteriovenous fistula is a rare intracranial congenital malformation (0.1-1: 100,000). It has a high blood flow between one or more pial arteries and drains into the venous circulation. It is usually diagnosed during the childhood by triggering an intracranial hypertension and/or congestive heart failure due to left-right systemic shunt. It is a rare malformation with a complex pathophysiology. The perioperative anaesthetic management is not well established. We present a 6-month-old infant diagnosed with pial arteriovenous fistula with hypertension and congestive heart failure due to left-right shunt. He required a craniotomy and clipping of vascular malformation. Anaesthetic considerations in patients with this condition are a great challenge. It must be performed by multidisciplinary teams with experience in paediatrics. The maintenance of blood volume during the intraoperative course is very important. Excessive fluid therapy can precipitate a congestive heart failure or intracranial hypertension, and a lower fluid therapy may cause a tissue hypoxia due to the bleeding. Copyright © 2015 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  13. Evaluation of two communication strategies to improve udder health management

    NARCIS (Netherlands)

    Jansen, J.; Renes, R.J.; Lam, T.J.G.M.

    2010-01-01

    Worldwide, programs to improve udder health are implemented using communication tools and methods that inform and persuade dairy farmers. This study evaluated 2 communication strategies used in a mastitis control program in the Netherlands. To improve farmers’ udder health management, tools such as

  14. Evaluation of two communication strategies to improve udder health management

    NARCIS (Netherlands)

    Jansen, J.; Renes, R.J.; Lam, T.J.G.M.

    2010-01-01

    Worldwide, programs to improve udder health are implemented using communication tools and methods that inform and persuade dairy farmers. This study evaluated 2 communication strategies used in a mastitis control program in the Netherlands. To improve farmers’ udder health management, tools such as

  15. Management Reviewing Literature: An Evaluation of Selected Characteristics.

    Science.gov (United States)

    Rehman, Sajjad ur

    1987-01-01

    Reports results of a study which compared the treatment of selected characteristics of the reviewing literature of management in professional and trade journals. The characteristics examined included lag time, review length, descriptive or analytic nature of reviews, positive or negative evaluations, and affiliation of the reviewer. (CLB)

  16. Course Evaluation: Reconfigurations for Learning with Learning Management Systems

    Science.gov (United States)

    Park, Ji Yong

    2014-01-01

    The introduction of online delivery platforms such as learning management systems (LMS) in tertiary education has changed the methods and modes of curriculum delivery and communication. While course evaluation methods have also changed from paper-based in-class-administered methods to largely online-administered methods, the data collection…

  17. Crisis Management in Youth Leadership - an Evaluation of Paul's ...

    African Journals Online (AJOL)

    Crisis Management in Youth Leadership - an Evaluation of Paul's teaching in 1 ... The men, women and youths constitute the lay members of the church with ... to face the challenges in the leadership cadre for the teaming population of the ...

  18. Evaluation and management of the patient with postoperative facial paralysis.

    Science.gov (United States)

    Hadlock, Tessa

    2012-05-01

    Postoperative facial paralysis comprises a spectrum of injuries ranging from mild, temporary weakness to severe, permanent paralysis, affecting as little as one muscle group to as much as the full hemiface. Herein is presented an introductory review of iatrogenic facial paralysis, from initial evaluation and decision making to the full range of conservative and operative management.

  19. Open Source Library Management Systems: A Multidimensional Evaluation

    Science.gov (United States)

    Balnaves, Edmund

    2008-01-01

    Open source library management systems have improved steadily in the last five years. They now present a credible option for small to medium libraries and library networks. An approach to their evaluation is proposed that takes account of three additional dimensions that only open source can offer: the developer and support community, the source…

  20. Open Source Library Management Systems: A Multidimensional Evaluation

    Science.gov (United States)

    Balnaves, Edmund

    2008-01-01

    Open source library management systems have improved steadily in the last five years. They now present a credible option for small to medium libraries and library networks. An approach to their evaluation is proposed that takes account of three additional dimensions that only open source can offer: the developer and support community, the source…

  1. Rotator Cuff Disease and Injury--Evaluation and Management.

    Science.gov (United States)

    Williams, Randy

    This presentation considers the incidence, evaluation, and management of rotator cuff disease and injury. Pathogenesis, symptoms, physical findings, treatment (therapeutic and surgical), and prevention are discussed. It is noted that rotator cuff problems, common in athletes, are usually related to an error in training or lack of training. They…

  2. Management Education Program Evaluation: An Empirical Study in Mainland China

    Science.gov (United States)

    Sou, Gryphon; Zhou, Pinqiu

    2007-01-01

    Background: With the accession of the PRC to the WTO, Chinese education market is open to the educational service providers of the foreign countries. They are keen to offer MBA Degree programs to the Career Managers in the Mainland. Aims: This research studies program evaluation and so forth the quality assessment of a MBA degree program in the…

  3. Evaluation of volcanic risk management in Merapi and Bromo Volcanoes

    Science.gov (United States)

    Bachri, S.; Stöetter, J.; Sartohadi, J.; Setiawan, M. A.

    2012-04-01

    Merapi (Central Java Province) and Bromo (East Java Province) volcanoes have human-environmental systems with unique characteristics, thus causing specific consequences on their risk management. Various efforts have been carried out by many parties (institutional government, scientists, and non-governmental organizations) to reduce the risk in these areas. However, it is likely that most of the actions have been done for temporary and partial purposes, leading to overlapping work and finally to a non-integrated scheme of volcanic risk management. This study, therefore, aims to identify and evaluate actions of risk and disaster reduction in Merapi and Bromo Volcanoes. To achieve this aims, a thorough literature review was carried out to identify earlier studies in both areas. Afterward, the basic concept of risk management cycle, consisting of risk assessment, risk reduction, event management and regeneration, is used to map those earlier studies and already implemented risk management actions in Merapi and Bromo. The results show that risk studies in Merapi have been developed predominantly on physical aspects of volcanic eruptions, i.e. models of lahar flows, hazard maps as well as other geophysical modeling. Furthermore, after the 2006 eruption of Merapi, research such on risk communication, social vulnerability, cultural vulnerability have appeared on the social side of risk management research. Apart from that, disaster risk management activities in the Bromo area were emphasizing on physical process and historical religious aspects. This overview of both study areas provides information on how risk studies have been used for managing the volcano disaster. This result confirms that most of earlier studies emphasize on the risk assessment and only few of them consider the risk reduction phase. Further investigation in this field work in the near future will accomplish the findings and contribute to formulate integrated volcanic risk management cycles for both

  4. University Knowledge Management Tool for Academic Research Activity Evaluation

    Directory of Open Access Journals (Sweden)

    Mihaela OPREA

    2011-01-01

    Full Text Available The implementation of an efficient university knowledge management system involves the de-velopment of several software tools that assist the decision making process for the three main activities of a university: teaching, research, and management. Artificial intelligence provides a variety of techniques that can be used by such tools: machine learning, data mining, text mining, knowledge based systems, expert systems, case-based reasoning, decision support systems, intelligent agents etc. In this paper it is proposed a generic structure of a university knowledge management system, and it is presented an expert system, ACDI_UPG, developed for academic research activity evaluation, that can be used as a decision support tool by the university knowledge management system for planning future research activities according to the main objectives of the university and of the national / international academic research funding organizations.

  5. Evaluation of Teachers' Opinions About Effective Classroom Management Practices

    Directory of Open Access Journals (Sweden)

    Soner DOĞAN

    2014-12-01

    Full Text Available The aim of this study is to evaluate teacher behaviour in creating an effective classroom management process with regard to the views of the teachers working in primary and secondary schools. This is a qualitative study in which the case study design was used. The related literature was scanned and 9 open-ended questions were prepared. These questions that based on maximum variation sampling method were posed to 18 teachers. The data were collected by interview forms and were examined by descriptive and content analysis methods. According to the findings obtained, teachers have stated that pre-determination of classroom rules, asking for students' advices, lecturing in a planned manner, planned teaching, various methods, communication skills, time management, being a model and transitions between activities affect the process of classroom management positively; while punishment affects it in a partly positive way and the differences among the discipline perceptions affect the classroom management negatively

  6. Evaluation in health: participatory methodology and involvement of municipal managers

    Science.gov (United States)

    de Almeida, Cristiane Andrea Locatelli; Tanaka, Oswaldo Yoshimi

    2016-01-01

    ABSTRACT OBJECTIVE To analyze scopes and limits of the use of participatory methodology of evaluation with municipal health managers and administrators. METHODS Qualitative research with health policymakers and managers of the Comissão Intergestores Regional (CIR – Regional Interagency Commission) of a health region of the state of Sao Paulo in Brazil. Representatives from seven member cities participated in seven workshops facilitated by the researchers, with the aim of assessing a specific problem of the care line, which would be used as a tracer of the system integrality. The analysis of the collected empirical material was based on the hermeneutic-dialectic methodology and aimed at the evaluation of the applied participatory methodology, according to its capacity of promoting a process of assessment capable to be used as a support for municipal management. RESULTS With the participatory approach of evaluation, we were able to promote in-depth discussions with the group, especially related to the construction of integral care and to the inclusion of the user’s perspective in decision-making, linked to the search for solution to concrete problems of managers. By joint exploration, the possibility of using data from electronic information systems was opened, as well as information coming directly from the users of the services, to enhance discussions and negotiations between partners. The participants were disbelievers of the replication potential of this type of evaluation without the direct monitoring of the academy, given the difficulty of organizing the process in everyday life, already taken by emergency and political issues. CONCLUSIONS Evaluations of programs and services carried out within the Regional Interagency Commission, starting from the local interest and facilitating the involvement of its members by the use of participatory methodologies, can contribute to the construction of integral care. To the extent that the act of evaluating stay

  7. Development of potential methods for testing congestion control algorithm implemented in vehicle to vehicle communications.

    Science.gov (United States)

    Hsu, Chung-Jen; Fikentscher, Joshua; Kreeb, Robert

    2017-03-21

    Objective A channel congestion problem might occur when the traffic density increases since the number of basic safety messages carried on the communication channel also increases in vehicle-to-vehicle communications. A remedy algorithm proposed in SAE J2945/1 is designed to address the channel congestion issue by decreasing transmission frequency and radiated power. This study is to develop potential test procedures for evaluating or validating the congestion control algorithm. Methods Simulations of a reference unit transmitting at a higher frequency are implemented to emulate a number of Onboard Equipment (OBE) transmitting at the normal interval of 100 milliseconds (10 Hz). When the transmitting interval is reduced to 1.25 milliseconds (800 Hz), the reference unit emulates 80 vehicles transmitting at 10 Hz. By increasing the number of reference units transmitting at 800 Hz in the simulations, the corresponding channel busy percentages are obtained. An algorithm for GPS data generation of virtual vehicles is developed for facilitating the validation of transmission intervals in the congestion control algorithm. Results Channel busy percentage is the channel busy time over a specified period of time. Three or four reference units are needed to generate channel busy percentages between 50% and 80%, and five reference units can generate channel busy percentages above 80%. The proposed test procedures can verify the operation of congestion control algorithm when channel busy percentages are between 50% and 80%, and above 80%. By using GPS data generation algorithm, the test procedures can also verify the transmission intervals when traffic densities are 80 and 200 vehicles in the radius of 100 m. A suite of test tools with functional requirements is also proposed for facilitating the implementation of test procedures. Conclusions The potential test procedures for congestion control algorithm are developed based on the simulation results of channel busy

  8. Serum Levels of Soluble Fas Ligand and Soluble Fas Receptor in Patients with Chronic Congestive Heart Failure

    Institute of Scientific and Technical Information of China (English)

    李刚; 令狐华; 魏良明

    2002-01-01

    @@ To understand the pathophysiologic significances of soluble Fas Ligand (sFasL) and soluble Fas receptor (sFas) in chronic congestive heart failure (CHF) and to determine the relationship of circulating levels of sFasL and sFas to the severity of CHF, the serum sFasL and sfas levels were evaluated in patients with CHF.

  9. METHODOLOGY FOR EVALUATION OF QUALITY MANAGEMENT SYSTEM EFFICIENCY

    Directory of Open Access Journals (Sweden)

    D. A. Yamnaja

    2010-01-01

    Full Text Available The National Technical Committee on standardization “Quality Control” has proposed a mechanism for evaluation of quality management system efficiency while applying experts’ appraisal by points – ТК РБ 4.2-МР-16–2002 which has a number of disadvantages and which is complicated for being used at enterprises. A methodology for evaluation of quality management system efficiency has been developed on the basis of a qualimetric approach to the formation of an experts’ group, working out of estimation scales and their realization, ТК РБ 4.2-МР-16–2002 propositions. The methodology has been put to evaluation test at the enterprise which is dealing with manufacturing and repair of railway products and can be applied at mechanical engineering and other enterprises

  10. [Development and clinical evaluation of an anesthesia information management system].

    Science.gov (United States)

    Feng, Jing-yi; Chen, Hua; Zhu, Sheng-mei

    2010-09-21

    To study the design, implementation and clinical evaluation of an anesthesia information management system. To record, process and store peri-operative patient data automatically, all kinds of bedside monitoring equipments are connected into the system based on information integrating technology; after a statistical analysis of those patient data by data mining technology, patient status can be evaluated automatically based on risk prediction standard and decision support system, and then anesthetist could perform reasonable and safe clinical processes; with clinical processes electronically recorded, standard record tables could be generated, and clinical workflow is optimized, as well. With the system, kinds of patient data could be collected, stored, analyzed and archived, kinds of anesthesia documents could be generated, and patient status could be evaluated to support clinic decision. The anesthesia information management system is useful for improving anesthesia quality, decreasing risk of patient and clinician, and aiding to provide clinical proof.

  11. Demand Side Management Performance Evaluation for Commercial Enterprises

    Directory of Open Access Journals (Sweden)

    Jun Dong

    2016-10-01

    Full Text Available Demand Side Management in power systems plays an important role in ensuring a reliable power supply and protecting the environment. Demand Side Management in the commercial sector is vital for sustainable development during China’s industrial restructuring. A hybrid multi-criteria decision making framework for evaluating Demand Side Management performance of commercial enterprises is proposed from a sustainability perspective. A fuzzy Analytic Hierarchy Process is employed to determine the weights of the criteria and a fuzzy technique for order preference by similarity to an ideal solution is applied to rank Demand Side Management performance. An evaluation index system is built, containing economic, social, environmental and technical criteria associated with 15 sub-criteria. Four groups of expert panels from government departments, research institutions, electricity utilities and commercial enterprises gave judgments on criteria weights and criteria performances for alternatives. The effectiveness of the proposed hybrid framework was demonstrated through a case study in Beijing, in which Demand Side Management performances of four alternatives were ranked. Sensitivity analysis results indicate that the hybrid framework is robust.

  12. Evaluating the effectiveness of pediatric pain management guidelines.

    Science.gov (United States)

    Habich, Michele; Wilson, Deeanna; Thielk, Dana; Melles, Grace L; Crumlett, Hillary S; Masterton, Joyce; McGuire, Julie

    2012-08-01

    In response to unit nursing quality and patient satisfaction concerns, the shared governance councils identified opportunities to improve overall assessment and management of pain in hospitalized pediatric patients. Together, the unit-shared governance councils evaluated current practice and reviewed the literature to develop comprehensive Pediatric Pain Assessment and Management Guidelines. The purpose of this study was to evaluate the effectiveness of implementing an evidence-based pain assessment and management guideline on nurses' knowledge, ability to assess and manage the patients' pain, and patient/family satisfaction with staff's management of pain. This intervention study with a pre-post design included three assessment intervals described as baseline and 3 and 6 months after guideline implementation. The sample included pediatric and pediatric intensive care unit (PICU) nursing staff, retrospective chart reviews of pediatric and PICU patients, and patient/parent satisfaction scores. No differences were found between nurses' knowledge and attitudes regarding pain before and after implementation of the guideline. Significant increases in pain assessment, use of correct tool, and reassessment were found following implementation. Although improving, there was no difference in patient/family satisfaction after guideline implementation. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Evaluating Effect of Knowledge Management Strategy on Human Resource Management Performance Using BSC Approach

    Directory of Open Access Journals (Sweden)

    Hossein Mansoori

    2012-02-01

    Full Text Available This research provided a model for evaluating the effect of knowledge management strategy on human resource management performance in higher education institutes and academic libraries. This research was a descriptive survey. According to the research literature and expert opinions, in human resource level, 38 indicators were produced for evaluating KM, then these indicators were classified in 10 total factors in terms of balanced scorecard approach. The results of evaluating knowledge management in Yazd academic libraries showed that, this strategy on customer perspectives, internal processes, learning and growth perspective had a good performance. But in terms of financial and Labor productivity indicators and training programs it did not have a good outcome for Yazd academic libraries.

  14. Evaluating herbivore management outcomes and associated vegetation impacts

    Directory of Open Access Journals (Sweden)

    Rina C.C. Grant

    2011-05-01

    Full Text Available African savannas are characterised by temporal and spatial fluxes that are linked to fluxes in herbivore populations and vegetation structure and composition. We need to be concerned about these fluxes only when management actions cause the system to shift towards a less desired state. Large herbivores are a key attribute of African savannas and are important for tourism and biodiversity. Large protected areas such as the Kruger National Park (KNP manage for high biodiversity as the desired state, whilst private protected areas, such as those adjacent to the KNP, generally manage for high income. Biodiversity, sustainability and economic indicators are thus required to flag thresholds of potential concern (TPCs that may result in a particular set of objectives not being achieved. In large conservation areas such as the KNP, vegetation changes that result from herbivore impact, or lack thereof, affect biodiversity and TPCs are used to indicate unacceptable change leading to a possible loss of biodiversity; in private protected areas the loss of large herbivores is seen as an important indicator of economic loss. Therefore, the first-level indicators aim to evaluate the forage available to sustain grazers without deleteriously affecting the vegetation composition, structure and basal cover. Various approaches to monitoring for these indicators were considered and the importance of the selection of sites that are representative of the intensity of herbivore use is emphasised. The most crucial step in the adaptive management process is the feedback of information to inform management decisions and enable learning. Feedback loops tend to be more efficient where the organisation’s vision is focused on, for example, economic gain, than in larger protected areas, such as the KNP, where the vision to conserve biodiversity is broader and more complex.Conservation implications: In rangeland, optimising herbivore numbers to achieve the management

  15. Qualitative research on the factors affecting long-term compliance to weight management of patients with congestive heart failure%充血性心力衰竭患者体质量管理长效依从性影响因素的质性研究

    Institute of Scientific and Technical Information of China (English)

    鞠阳; 王琪; 仇静波; 汪小华; 蒋青; 陆敏霞; 杨小芳

    2013-01-01

    目的 探讨充血性心力衰竭(congestive heart failure,CHF)患者体质量管理长效依从性的影响因素,为提高患者依从性提供依据.方法 应用强化理论对18例参与体质量管理≥6个月的CHF患者进行半结构式访谈,并采用Colaizzi分析程序对访谈资料进行整理和分析.结果 归纳为3个主题:(1)体质量管理行为产生的促发因素,包括对疾病的正确感知和自我效能;(2)体质量管理行为维持的正强化因素:包括早期获益、再入院、随访、家人和社会支持;(3)体质量管理行为维持的负强化因素包括长期未获益和身心障碍.上述因素的作用导致50%访谈对象的体质量管理长效依从性呈动态性波动变化.结论 医护人员应在随访过程中及时发现CHF患者依从性的变化,分析影响其依从性的因素,从而把握最佳干预时机,采取针对性、多形式、多角度的健康教育以提高依从性.%Objective To explore factors affecting long-term compliance to weight management (WM) of patients with congestive heart failure (CHF)and to provide evidence for improving patients' compliance.Methods In-depth semi-structured interviews based on reinforcement theory were conducted among 18 CHF patients who received WM intervention over 6 months.The data were analyzed by Colaizzi analysis program.Results Three themes were found:precipitating factors such as the correct perception of disease and self-efficacy,the factors of positive reinforcement such as early gains from WM,readmission,follow-up,family and social support,as well as the factors of negative reinforcement such as gaining nothing during long period,physical and mental disorders.These above factors made long-term compliance to WM of 50% of the participants dynamic and fluctuant.Conclusions Medical staff should identify patients'compliance at different stages in time during follow-up,analyze the factors that affect their compliance,and then grasp the optimal timing

  16. New Knowledge Network Evaluation Method for Design Rationale Management

    Institute of Scientific and Technical Information of China (English)

    JING Shikai; ZHAN Hongfei; LIU Jihong; WANG Kuan; JIANG Hao; ZHOU Jingtao

    2015-01-01

    Current design rationale (DR) systems have not demonstrated the value of the approach in practice since little attention is put to the evaluation method of DR knowledge. To systematize knowledge management process for future computer-aided DR applications, a prerequisite is to provide the measure for the DR knowledge. In this paper, a new knowledge network evaluation method for DR management is presented. The method characterizes the DR knowledge value from four perspectives, namely, the design rationale structure scale, association knowledge and reasoning ability, degree of design justification support and degree of knowledge representation conciseness. The DR knowledge comprehensive value is also measured by the proposed method. To validate the proposed method, different style of DR knowledge network and the performance of the proposed measure are discussed. The evaluation method has been applied in two realistic design cases and compared with the structural measures. The research proposes the DR knowledge evaluation method which can provide object metric and selection basis for the DR knowledge reuse during the product design process. In addition, the method is proved to be more effective guidance and support for the application and management of DR knowledge.

  17. Traffic conflict assessment for non-lane-based movements of motorcycles under congested conditions

    Directory of Open Access Journals (Sweden)

    Long Xuan Nguyen

    2014-03-01

    Full Text Available Traffic conflict under congested conditions is one of the main safety issues of motorcycle traffic in developing countries. Unlike cars, motorcycles often display non-lane-based movements such as swerving or oblique following of a lead vehicle when traffic becomes congested. Very few studies have quantitatively evaluated the effects of such non-lane-based movements on traffic conflict. Therefore, in this study we aim to develop an integrated model to assess the traffic conflict of motorcycles under congested conditions. The proposed model includes a concept of safety space to describe the non-lane-based movements unique to motorcycles, new features developed for traffic conflict assessment such as parameters of acceleration and deceleration, and the conditions for choosing a lead vehicle. Calibration data were extracted from video clips taken at two road segments in Ho Chi Minh City. A simulation based on the model was developed to verify the dynamic non-lane-based movements of motorcycles. Subsequently, the assessment of traffic conflict was validated by calculating the probability of sudden braking at each time interval according to the change in the density of motorcycle flow. Our findings underscore the fact that higher flow density may lead to conflicts associated with a greater probability of sudden breaking. Three types of motorcycle traffic conflicts were confirmed, and the proportions of each type were calculated and discussed.

  18. FOUR-YEAR-OLD NAMSAN TUNNEL CONGESTION PRICING SCHEME IN SEOUL

    Directory of Open Access Journals (Sweden)

    Bongsoo SON, Ph. D.

    2002-01-01

    Full Text Available The purpose of this paper is to evaluate the effectiveness of the congestion pricing scheme at Namsan #1 and #3 tunnels in downtown Seoul four years after its implementation. The effectiveness of the scheme was measured by the changes of various traffic impacts. The traffic volume of the two tunnels was reduced by up to 25% for the first month. After that time, the traffic volume started to increase again and then exceeded the previous volume level. However, average travel speed of the two tunnel corridors improved by up to 74%. The overall traffic volume of the four alternative routes was increased; nevertheless, their average travel speed increased as well. The number of carpool vehicles occupied by 3 or more persons including the driver during the peak periods was remarkably increased. Before the congestion fee charging, toll-charged vehicles amounted to 68.5% of the total traffic volume of the two tunnels, and then the share dropped to 29% afterwards. The empirical analysis results for the effectiveness of the congestion pricing scheme are very promising.

  19. A Novel Congestion Avoidance Technique for Simultaneous Real-Time Medical Data Transmission.

    Science.gov (United States)

    Yaakob, Naimah; Khalil, Ibrahim

    2016-03-01

    The use of wireless body sensor networks (WBSN) in medical services aims at providing continuous monitoring of patients' physiological data. However, the scarce resources in WBSN nodes limit their capabilities to cope with massive traffic during multiple, simultaneous data transmissions. This will create a high tendency for congestion, causing severe performance degradation. Congestion may lead to high number of packet loss and unbounded delay which are critical and may lead to wrong diagnosis. This paper, therefore, aims at improving this limitation using a novel congestion avoidance technique to avoid losing real-time and life-critical medical data (e.g., electrocardiogram and electroencephalography) which are vital for diagnosis. The main idea is to integrate the existing rate control scheme of relaxation theory (RT) with a method known as max-min fairness (MMF) to achieve better performance. The MMF can be accomplished using a progressive filling algorithm, which cuts-down excessive sending rates that may overwhelme the limited buffer in WBSN. This paper builds upon our prior study, which provides a preliminary analysis of RT technique in single node. Our current technique integrates the MMF phase to enhance RT performance when the transmission rates exceed certain threshold. Performance evaluation on RT-MMF technique shows remarkable performance improvements, while maintaining the desired quality of service.

  20. REDUCTION IN PROBABILITY OF TRAFFIC CONGESTION ON HIGH-CLASS ROAD USING RAMP ACCESS CONTROL

    Directory of Open Access Journals (Sweden)

    R. Yu. Lagerev

    2016-01-01

    Full Text Available Мerging traffic junctions on high-class roads are considered as bottlenecks in the network and quality of their operation determines a probability for formation of traffic congestions. Investigations on congestion situations in the merging zones of ramp and freeway traffic flows have demonstrated that queuing ramp traffic flow leads to formation of so called “turbulence” effect due to re-arrangement of transport facilities and reduction in their speed on main road direction. Having high queuing traffic flow on main road the “turbulence” component can result in formation of an impact blow in the main traffic flow. It has been proved that an impact of the ramp traffic flow on congestion probability is higher in comparison with main road traffic flow. The paper makes it possible to establish that some transport facilities moving along a high-way simul taneously occupy two lanes in the merging traffic zones and they reduce capacity of the used road section. It is necessary to take into account this specific feature and it is necessary to pay attention to it in the zones of “turbulence” effect formation. The paper presents main approaches, methodology, principles and stages required for access control of high-class roads which are directed on higher quality of their operation including improvement of road traffic safety. The paper proposes a methodоlogy that allows to evaluate and optimize ramp control in the context of a transport queue length minimization at adjoining ramps for the purposes of probability reduction in transport congestion.

  1. Analytical Study of Pre-Congestion Notification (PCN Techniques

    Directory of Open Access Journals (Sweden)

    Marwah Almasri

    2012-08-01

    Full Text Available Maintaining the quality of service (QOS and controlling the network congestion are quite complicated tasks. They cause degrading the performance of the network, and disturbing the continuous communication process. To overcome these issues, one step towards this dilemma has been taken in form of Pre-congestion notification (PCN technique. PCN uses a packet marking technique within a PCN domain over IP networks. It is notified by egress node that works as guard at entry point of network. Egress node gives feedback to communicating servers whether rate on the link is exceeded than configured admissible threshold or within the limit. Based on this feedback, admission decisions are taken to determine whether to allow/block new coming flows or terminate already accepted. The actual question is about selection of right algorithm for PCN domain. In this paper, we investigate the analytical behavior of some known PCN algorithms. We make slide modifications in originality of PCN algorithms without disquieting working process in order to employ those within similar types of scenarios. Our goal is to simulate them either in highly congested or less congested realistic scenarios. On the basis of simulation done in ns2, we are able to recommend each PCN algorithm for specific conditions. Finally, we develop a benchmark that helps researchers and scientific communities to pick the right algorithm. Furthermore, the benchmark is designed to achieve specific objectives according to the users’ requirements without congesting the network.

  2. Traffic Congestion Detection and Avoidance using Vehicular Communication

    Directory of Open Access Journals (Sweden)

    Ajay Narendrabhai Upadhyaya

    2015-01-01

    Full Text Available Traffic congestion is a serious problem in big cities. With the number of vehicles increasing rapidly, especially in cities whose economy is booming, the situation is getting even worse. Drivers, unaware of congestion ahead eventually join it and increase the severity of it. The ability of a driver to know the traffic conditions on the roads ahead enables him/her to seek alternate routes through which time and fuel can be saved. Due to recent advancements in vehicular technologies, vehicular communication has emerged. The objective of this work is to check feasibility of using infrastructure based vehicular communication for detecting and avoiding traffic congestion. In this paper we propose a Signal Agent (SA and Car Agent(CAbased approach for detecting and avoiding traffic congestion. We analyze performance of the proposed approach for two different road network scenarios using simulations: structured grid network (like Gandhinagar City of Gujarat, India and apart of typical city road network ( Tiwan city. With the proposed approach we get reduction of 10.05% in trip duration of vehicles, reduction of 10.08% in number of vehicles in entire traffic road network and 9.82% in heavy traffic area. In an accident scenario, about 72.63% vehicles changed their route due to awareness of congestion. Error in trip time estimation and vehicle count estimation is observed to be less than 1%.

  3. Towards Scalable Distributed Framework for Urban Congestion Traffic Patterns Warehousing

    Directory of Open Access Journals (Sweden)

    A. Boulmakoul

    2015-01-01

    Full Text Available We put forward architecture of a framework for integration of data from moving objects related to urban transportation network. Most of this research refers to the GPS outdoor geolocation technology and uses distributed cloud infrastructure with big data NoSQL database. A network of intelligent mobile sensors, distributed on urban network, produces congestion traffic patterns. Congestion predictions are based on extended simulation model. This model provides traffic indicators calculations, which fuse with the GPS data for allowing estimation of traffic states across the whole network. The discovery process of congestion patterns uses semantic trajectories metamodel given in our previous works. The challenge of the proposed solution is to store patterns of traffic, which aims to ensure the surveillance and intelligent real-time control network to reduce congestion and avoid its consequences. The fusion of real-time data from GPS-enabled smartphones integrated with those provided by existing traffic systems improves traffic congestion knowledge, as well as generating new information for a soft operational control and providing intelligent added value for transportation systems deployment.

  4. A Novel Congestion Detection Scheme in TCP Over OBS Networks

    KAUST Repository

    Shihada, Basem

    2009-02-01

    This paper introduces a novel congestion detection scheme for high-bandwidth TCP flows over optical burst switching (OBS) networks, called statistical additive increase multiplicative decrease (SAIMD). SAIMD maintains and analyzes a number of previous round-trip time (RTTs) at the TCP senders in order to identify the confidence with which a packet loss event is due to network congestion. The confidence is derived by positioning short-term RTT in the spectrum of long-term historical RTTs. The derived confidence corresponding to the packet loss is then taken in the developed policy for TCP congestion window adjustment. We will show through extensive simulation that the proposed scheme can effectively solve the false congestion detection problem and significantly outperform the conventional TCP counterparts without losing fairness. The advantages gained in our scheme are at the expense of introducing more overhead in the SAIMD TCP senders. Based on the proposed congestion control algorithm, a throughput model is formulated, and is further verified by simulation results.

  5. Distributed Optimal Control of Smart Electricity Grids With Congestion Management

    NARCIS (Netherlands)

    Nguyen, Dinh Bao; Scherpen, Jacquelien M.A.; Bliek, F

    2017-01-01

    In this paper, we consider the balancing problem in a hierarchical market-based structure for smart energy grids that is based on the Universal Smart Energy Framework. The large-scale introduction of renewable, intermittent energy sources in the power system can create a mismatch between the forecas

  6. Distributed Optimal Control of Smart Energy Grids with Congestion Management

    NARCIS (Netherlands)

    Nguyen, Dinh Bao; Scherpen, Jacquelien M.A.; Kramer, Hendrik; Bliek, F; Larsen, Gunn; Carloni, Raffaella; Jeltsema, Dimitri; Lazar, ircea

    2016-01-01

    One of the big challenges in the transition towards smart grids is how to deal with the intermittent nature of renewable energy resources such as wind or solar energy. For example, a prediction of the electricity supply and demand is typically made a day ahead, but the actual supply during operation

  7. Congestion management in a smart grid via shadow prices

    DEFF Research Database (Denmark)

    Biegel, Benjamin; Andersen, Palle; Stoustrup, Jakob

    2012-01-01

    We consider a distribution grid interconnecting a number of consumers with flexible power consumption. Each consumer is under the jurisdiction of exactly one balancing responsible party (BRP), who buys energy at a day-ahead electricity market on behalf of the consumer. We illustrate how BRPs can ...

  8. Performance management in the Slovak higher education system: preliminary evaluation

    Directory of Open Access Journals (Sweden)

    Juraj Nemec

    2007-10-01

    Full Text Available The aim of our paper is a preliminary evaluation of the introduction of performance management and performance financing arrangements in the Slovak higher education system – accreditation and formula based performance financing. This evaluation will be mainly based on the assessment of short-term impacts of the above mentioned instruments and is expected to invite further professional discussion. We feel that the data and brief analysis included are sufficient enough to show that the Slovak system represents a typical example of the potential of performance management and performance financing being significantly limited, if not destroyed. Not only because of improperly defined indicators, which are too much input and quantity orientated, but very much also due to a lack of resources (the ratio of public expenditures for higher education to the GDP in Slovakia is significantly below EU average, as well as the politicization of the system.

  9. Evaluation of dairy effluent management options using multiple criteria analysis.

    Science.gov (United States)

    Hajkowicz, Stefan A; Wheeler, Sarah A

    2008-04-01

    This article describes how options for managing dairy effluent on the Lower Murray River in South Australia were evaluated using multiple criteria analysis (MCA). Multiple criteria analysis is a framework for combining multiple environmental, social, and economic objectives in policy decisions. At the time of the study, dairy irrigation in the region was based on flood irrigation which involved returning effluent to the river. The returned water contained nutrients, salts, and microbial contaminants leading to environmental, human health, and tourism impacts. In this study MCA was used to evaluate 11 options against 6 criteria for managing dairy effluent problems. Of the 11 options, the MCA model selected partial rehabilitation of dairy paddocks with the conversion of remaining land to other agriculture. Soon after, the South Australian Government adopted this course of action and is now providing incentives for dairy farmers in the region to upgrade irrigation infrastructure and/or enter alternative industries.

  10. Evaluation of Dairy Effluent Management Options Using Multiple Criteria Analysis

    Science.gov (United States)

    Hajkowicz, Stefan A.; Wheeler, Sarah A.

    2008-04-01

    This article describes how options for managing dairy effluent on the Lower Murray River in South Australia were evaluated using multiple criteria analysis (MCA). Multiple criteria analysis is a framework for combining multiple environmental, social, and economic objectives in policy decisions. At the time of the study, dairy irrigation in the region was based on flood irrigation which involved returning effluent to the river. The returned water contained nutrients, salts, and microbial contaminants leading to environmental, human health, and tourism impacts. In this study MCA was used to evaluate 11 options against 6 criteria for managing dairy effluent problems. Of the 11 options, the MCA model selected partial rehabilitation of dairy paddocks with the conversion of remaining land to other agriculture. Soon after, the South Australian Government adopted this course of action and is now providing incentives for dairy farmers in the region to upgrade irrigation infrastructure and/or enter alternative industries.

  11. NOTION, ELEMENTS AND EVALUATION OF HUMAN RESOURCES MANAGMENT IN SPORT

    Directory of Open Access Journals (Sweden)

    Milorad M. Drobac

    2009-11-01

    Full Text Available Principal object of the author’s research in work is identification of notion, cru- cial elements and evaluation of human resources management in general and apart in sport. From the beginning of usage of term “human resources management”, we use foretoken “strategic” that has especially signified meaning. Strategic approach to the exploration of this problem points to the fact that human resources are from particularly significance for all forms of human organization (firms, associations, institutions etc., regardless are we talking about economy, social activity, politics, science, sport or any other area of human activity. Experience shows that, in our society, we mainly considered human resources management from the aspect of formulation and implementation of strategy in any shape and segment of altogether human activity, but we pay a little interest to the control, or in other words evaluation of human resources performance. What is attained in world rela- tions, on the human resources management plan, admonish and binds that we must ac- cept employees in our environment (it implies sport as an equal partner in management

  12. Analysis and Improvement of TCP Congestion Control Mechanism Based on Global Optimization Model

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Network flow control is formulated as a global optimization problem of user profit. A general global optimization flow control model is established. This model combined with the stochastic model of TCP is used to study the global rate allocation characteristic of TCP. Analysis shows when active queue manage ment is used in network TCP rates tend to be allocated to maximize the aggregate of a user utility function Us (called Us fairness). The TCP throughput formula is derived. An improved TCP congestion control mecha nism is proposed. Simulations show its throughput is TCP friendly when competing with existing TCP and its rate change is smoother. Therefore, it is suitable to carry multimedia applications.

  13. A perspective on sympathetic renal denervation in chronic congestive heart failure.

    Science.gov (United States)

    Madanieh, Raef; El-Hunjul, Mohammed; Alkhawam, Hassan; Kosmas, Constantine E; Madanieh, Abed; Vittorio, Timothy J

    2016-01-01

    Medical therapy has indisputably been the mainstay of management for chronic congestive heart failure. However, a significant percentage of patients continue to experience worsening heart failure (HF) symptoms despite treatment with multiple therapeutic agents. Recently, catheter-based interventional strategies that interrupt the renal sympathetic nervous system have shown promising results in providing better symptom control in patients with HF. In this article, we will review the pathophysiology of HF for better understanding of the interplay between the cardiovascular system and the kidney. Subsequently, we will briefly discuss pivotal renal denervation (RDN) therapy trials in patients with resistant hypertension and then present the available evidence on the role of RDN in HF therapy.

  14. Role and Importance of Evaluation in Management Enterprise

    Directory of Open Access Journals (Sweden)

    Mihaela NICOARA

    2012-11-01

    Full Text Available In determining the enterprise value is assessed, are taken into account all areas that help to generate future profits in the întreprindrii evaluated, respectively. In this respect, a special role is managerial decision.This is the main tool to achieve business objectives, which should be based on past actual situation of the enterprise, the current existing ralitatile on forecasting ability, but also work with other specialisti.Rezultatele assessment is an important source of decision management.

  15. [Initial evaluation and management of paroxysmal supraventricular tachycardia].

    Science.gov (United States)

    Rujic, Dragana; Sundbøll, Jens; Tofig, Bawer Jalal; Nielsen, Jens Cosedis; Pareek, Manan

    2016-01-18

    The paroxysmal supraventricular tachycardias (SVT) are commonly encountered arrhythmias and include atrioventricular nodal re-entrant tachycardia, atrioventricular reciprocating tachycardia, and focal atrial tachycardia. These tachycardias share several clinical features as well as similar management strategies. The probable mechanism of paroxysmal SVT can often be diagnosed from the clinical findings and a 12-lead ECG. This review describes the initial evaluation and treatment of patients with paroxysmal SVT, including distinctive features from the most important differential diagnoses.

  16. Comparative Evaluation of Supply Chain Management Strategies: A Simulation Approach

    OpenAIRE

    Chan, FTS

    2002-01-01

    Supply chain management has become one of the most important sources of competitive advantage in different industries. For years, researchers have investigated the various processes within supply chain. There has been an increasing attention placed on performance, design and analysis of supply chain. However, the supply chain is a complex model so it is difficult to analyze the performance of a supply chain philosophically. To evaluate the control mechanism for a supply chain, simulation is o...

  17. Methods of Human Resource Management Evaluation and Directions for Their Improvement in Large Enterprises of Latvia

    OpenAIRE

    Peiseniece, Līga

    2011-01-01

    The goal of the dissertation „Methods of Human Resource Management Evaluation and Directions for Their Improvement in Large Enterprises of Latvia” is to establish new methods for efficiency evaluation of human resource management to improve processes of human resource management in large enterprises of Latvia. The first chapter covers the nature and methods of evaluation of human resource management. The necessity of evaluation of human resource management has been based ...

  18. Performance study of Active Queue Management methods: Adaptive GRED, REDD, and GRED-Linear analytical model

    Directory of Open Access Journals (Sweden)

    Hussein Abdel-jaber

    2015-10-01

    Full Text Available Congestion control is one of the hot research topics that helps maintain the performance of computer networks. This paper compares three Active Queue Management (AQM methods, namely, Adaptive Gentle Random Early Detection (Adaptive GRED, Random Early Dynamic Detection (REDD, and GRED Linear analytical model with respect to different performance measures. Adaptive GRED and REDD are implemented based on simulation, whereas GRED Linear is implemented as a discrete-time analytical model. Several performance measures are used to evaluate the effectiveness of the compared methods mainly mean queue length, throughput, average queueing delay, overflow packet loss probability, and packet dropping probability. The ultimate aim is to identify the method that offers the highest satisfactory performance in non-congestion or congestion scenarios. The first comparison results that are based on different packet arrival probability values show that GRED Linear provides better mean queue length; average queueing delay and packet overflow probability than Adaptive GRED and REDD methods in the presence of congestion. Further and using the same evaluation measures, Adaptive GRED offers a more satisfactory performance than REDD when heavy congestion is present. When the finite capacity of queue values varies the GRED Linear model provides the highest satisfactory performance with reference to mean queue length and average queueing delay and all the compared methods provide similar throughput performance. However, when the finite capacity value is large, the compared methods have similar results in regard to probabilities of both packet overflowing and packet dropping.

  19. A Community Hospital's Evaluation of Alarm Management Safety Factors.

    Science.gov (United States)

    Kurnat-Thoma, Emma; Shah, Kayuri

    2016-12-01

    The Joint Commission's 2014 National Patient Safety Goals required hospitals to evaluate alarm safety in 2014-2015 and implement alarm safety policies. The aim of this study was to assess common alarm management safety factors in our 187-bed community hospital. Two weeks' worth of IV pump report data was evaluated to characterize 33 IV pump alarm types. Hospital and IV pump noise was measured, and an alarm management nurse survey was conducted. There were 8731 total IV pump alarms/alerts (24-hour mean, 623.6) across 6 units. The 2-minute idle alarm accounted for 32.4% of all total IV alarms/alerts, suggestive of high levels of nurse multitasking and nurse work interruptions. IV pump volumes contributed to overall hospital noise. Survey data identified patient units and alarm safety practices needing additional support. Characterization of IV pump alarms/alerts is an emerging area of scientific inquiry. Findings indicate the need for organizations to evaluate alarm burden and alarm management safety practices to reduce alarm fatigue risks.

  20. Management strategy evaluation applied to coral reef ecosystems in support of ecosystem-based management

    NARCIS (Netherlands)

    Weijerman, M.; Fulton, Elizabeth A.; Brainard, Russell E.

    2016-01-01

    Ecosystem modelling is increasingly used to explore ecosystem-level effects of changing environmental conditions and management actions. For coral reefs there has been increasing interest in recent decades in the use of ecosystem models for evaluating the effects of fishing and the efficacy of ma

  1. Increasing Intelligence in Inter-Vehicle Communications to Reduce Traffic Congestions: Experiments in Urban and Highway Environments

    Science.gov (United States)

    Filho, Geraldo P. R.; Guidoni, Daniel L.; Pessin, Gustavo; Villas, Leandro A.; Ueyama, Jó

    2016-01-01

    Intelligent Transportation Systems (ITS) rely on Inter-Vehicle Communication (IVC) to streamline the operation of vehicles by managing vehicle traffic, assisting drivers with safety and sharing information, as well as providing appropriate services for passengers. Traffic congestion is an urban mobility problem, which causes stress to drivers and economic losses. In this context, this work proposes a solution for the detection, dissemination and control of congested roads based on inter-vehicle communication, called INCIDEnT. The main goal of the proposed solution is to reduce the average trip time, CO emissions and fuel consumption by allowing motorists to avoid congested roads. The simulation results show that our proposed solution leads to short delays and a low overhead. Moreover, it is efficient with regard to the coverage of the event and the distance to which the information can be propagated. The findings of the investigation show that the proposed solution leads to (i) high hit rate in the classification of the level of congestion, (ii) a reduction in average trip time, (iii) a reduction in fuel consumption, and (iv) reduced CO emissions PMID:27526048

  2. Increasing Intelligence in Inter-Vehicle Communications to Reduce Traffic Congestions: Experiments in Urban and Highway Environments.

    Science.gov (United States)

    Meneguette, Rodolfo I; Filho, Geraldo P R; Guidoni, Daniel L; Pessin, Gustavo; Villas, Leandro A; Ueyama, Jó

    2016-01-01

    Intelligent Transportation Systems (ITS) rely on Inter-Vehicle Communication (IVC) to streamline the operation of vehicles by managing vehicle traffic, assisting drivers with safety and sharing information, as well as providing appropriate services for passengers. Traffic congestion is an urban mobility problem, which causes stress to drivers and economic losses. In this context, this work proposes a solution for the detection, dissemination and control of congested roads based on inter-vehicle communication, called INCIDEnT. The main goal of the proposed solution is to reduce the average trip time, CO emissions and fuel consumption by allowing motorists to avoid congested roads. The simulation results show that our proposed solution leads to short delays and a low overhead. Moreover, it is efficient with regard to the coverage of the event and the distance to which the information can be propagated. The findings of the investigation show that the proposed solution leads to (i) high hit rate in the classification of the level of congestion, (ii) a reduction in average trip time, (iii) a reduction in fuel consumption, and (iv) reduced CO emissions.

  3. Involvement of systemic venous congestion in heart failure.

    Science.gov (United States)

    Rubio Gracia, J; Sánchez Marteles, M; Pérez Calvo, J I

    2017-04-01

    Systemic venous congestion has gained significant importance in the interpretation of the pathophysiology of acute heart failure, especially in the development of renal function impairment during exacerbations. In this study, we review the concept, clinical characterisation and identification of venous congestion. We update current knowledge on its importance in the pathophysiology of acute heart failure and its involvement in the prognosis. We pay special attention to the relationship between abdominal congestion, the pulmonary interstitium as filtering membrane, inflammatory phenomena and renal function impairment in acute heart failure. Lastly, we review decongestion as a new therapeutic objective and the measures available for its assessment. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Medicina Interna (SEMI). All rights reserved.

  4. Congestion induced by the structure of multiplex networks

    CERN Document Server

    Solé-Ribalta, Albert; Arenas, Alex

    2016-01-01

    Multiplex networks are representations of multilayer interconnected complex networks where the nodes are the same at every layer. They turn out to be good abstractions of the intricate connectivity of multimodal transportation networks, among other types of complex systems. One of the most important critical phenomena arising in such networks is the emergence of congestion in transportation flows. Here we prove analytically that the structure of multiplex networks can induce congestion for flows that otherwise will be decongested if the individual layers were not interconnected. We provide explicit equations for the onset of congestion and approximations that allow to compute this onset from individual descriptors of the individual layers. The observed cooperative phenomenon reminds the Braess' paradox in which adding extra capacity to a network when the moving entities selfishly choose their route can in some cases reduce overall performance. Similarly, in the multiplex structure, the efficiency in transport...

  5. Using Crowd Sensed Data as Input to Congestion Model

    DEFF Research Database (Denmark)

    Lehmann, Anders; Gross, Allan

    2016-01-01

    . To get accurate and timely information on traffic congestion, and by extension information on air pollution, near real time traffic models are needed. We present in this paper an implementation of the Restricted Stochastic User equilibrium model, that is capable to model congestions for very large Urban......Emission of airborne pollutants and climate gasses from the transport sector is a growing problem, both in indus- trialised and developing countries. Planning of urban transport system is essential to minimise the environmental, health and economic impact of congestion in the transport system...... traffic systems, in less than an hour. The model is implemented in an open source database system, for easy interface with GIS resources and crowd sensed transportation data....

  6. Road Transport Congestion Costs Calculations-Adaptation to Engineering Approach

    Directory of Open Access Journals (Sweden)

    Marjan Lep

    2008-01-01

    Full Text Available The article represents so called “engineering” approach for computing the total road transport congestion costs. According to economic welfare theory, the total costs of transport congestion are defined as dead weight loss (DWL of infrastructure use. With a set of equations DWL could be formulated in a mathematical way. Because such form of equation is not directly applicable for concrete road network calculations it should be transformed into “engineering” form, which comprises transport engineering related data as classified road links, traffic volumes, passenger unit costs, etc. The equation is well applicable on the interurban road network; adaptations are needed for the urban road network cost calculations, where time losses are not so much related to the link travel time. The final equation was derived for the purposes of national road congestion cost calculation.

  7. Reliability and Congestion Effects on Embedded Cost of Transmission Services

    Science.gov (United States)

    Shooshtari, Alireza Tavakoli; Joorabian, Mahmood; Milani, Armin Ebrahimi

    2011-06-01

    The aim of this paper is to make a novel method for calculating the investment cost of Transmission services. It should be noted that some considerations such as used capacity, profits of reliability and profits of decreasing congestion-the money allocated to transmission services- are also taken into account. The proposed method is tested on an 8 bus test system. All simulations are done in MATLAB environment, and MATPOWER is used for Power Flow Analysis. In order to verify the proposed method, the optimal results are compared with the pervious techniques. Therefore, the proposed technique in the paper has important effects on investment on transmission network by improving the profits of reliability and decreasing congestion. Furthermore, simulations show that increasing maximum acceptable level of current will decrease the profit of decreasing congestion.

  8. A Circuit Simulation Technique for Congested Network Traffic Assignment Problem

    Science.gov (United States)

    Cho, Hsun-Jung; Huang, Heng

    2007-12-01

    The relation between electrical circuit and traffic network has been proposed by Sasaki and Inouye, but they proposed link cost function is a linear function which cannot present the congestion situation. Cho and Huang extended the link cost function to a nonlinear function which can explain the congested network. In this paper, we proposed a foremost and novel approach to solve the traffic assignment problem (TAP) by simulating the electrical circuit network which consists of nonlinear link cost function models. Comparing with the solutions of Frank-Wolfe algorithm, the simulation results are nearly identical. Thus, the simulation of a network circuit model can be applied to solve network traffic assignment problems. Finally, two examples are proposed, and the results confirmed that electrical circuit simulation is workable in solving congested network traffic assignment problems.

  9. Training evaluation: a case study of training Iranian health managers

    Directory of Open Access Journals (Sweden)

    Butcher Christopher

    2009-03-01

    Full Text Available Abstract Background The Ministry of Health and Medical Education in the Islamic Republic of Iran has undertaken a reform of its health system, in which-lower level managers are given new roles and responsibilities in a decentralized system. To support these efforts, a United Kingdom-based university was contracted by the World Health Organization to design a series of courses for health managers and trainers. This process was also intended to develop the capacity of the National Public Health Management Centre in Tabriz, Iran, to enable it to organize relevant short courses in health management on a continuing basis. A total of seven short training courses were implemented, three in the United Kingdom and four in Tabriz, with 35 participants. A detailed evaluation of the courses was undertaken to guide future development of the training programmes. Methods The Kirkpatrick framework for evaluation of training was used to measure participants' reactions, learning, application to the job, and to a lesser extent, organizational impact. Particular emphasis was put on application of learning to the participants' job. A structured questionnaire was administered to 23 participants, out of 35, between one and 13 months after they had attended the courses. Respondents, like the training course participants, were predominantly from provincial universities, with both health system and academic responsibilities. Interviews with key informants and ex-trainees provided supplemental information, especially on organizational impact. Results Participants' preferred interactive methods for learning about health planning and management. They found the course content to be relevant, but with an overemphasis on theory compared to practical, locally-specific information. In terms of application of learning to their jobs, participants found specific information and skills to be most useful, such as health systems research and group work/problem solving. The least

  10. Tournament MAC with Constant Size Congestion Window for WLAN

    CERN Document Server

    Galtier, Jerome

    2007-01-01

    In the context of radio distributed networks, we present a generalized approach for the Medium Access Control (MAC) with fixed congestion window. Our protocol is quite simple to analyze and can be used in a lot of different situations. We give mathematical evidence showing that our performance is tight, in the sense that no protocol with fixed congestion window can do better. We also place ourselves in the WiFi/WiMAX framework, and show experimental results enlightening collision reduction of 14% to 21% compared to the best known other methods. We show channel capacity improvement, and fairness considerations.

  11. Congestion estimation technique in the optical network unit registration process.

    Science.gov (United States)

    Kim, Geunyong; Yoo, Hark; Lee, Dongsoo; Kim, Youngsun; Lim, Hyuk

    2016-07-01

    We present a congestion estimation technique (CET) to estimate the optical network unit (ONU) registration success ratio for the ONU registration process in passive optical networks. An optical line terminal (OLT) estimates the number of collided ONUs via the proposed scheme during the serial number state. The OLT can obtain congestion level among ONUs to be registered such that this information may be exploited to change the size of a quiet window to decrease the collision probability. We verified the efficiency of the proposed method through simulation and experimental results.

  12. Congestion in a city with a central bottleneck

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Palma, André de

    2010-01-01

    , travelers sort according to their distance to the destination. We construct a welfare maximizing tolling regime, which eliminates congestion. All travelers located beyond a critical distance from the CBD gain from tolling, even when toll revenues are not redistributed, while nearby travelers lose. We......We consider dynamic congestion in an urban setting where trip origins are spatially distributed. All travelers must pass through a downtown bottleneck in order to reach their destination in the CBD. Each traveler chooses departure time to maximize general concave scheduling utility. At equilibrium...

  13. Gene transfer for congestive heart failure: update 2013.

    Science.gov (United States)

    Tang, Tong; Hammond, H Kirk

    2013-04-01

    Congestive heart failure is a major cause of morbidity and mortality with increasing social and economic costs. There have been no new high impact therapeutic agents for this devastating disease for more than a decade. However, many pivotal regulators of cardiac function have been identified using cardiac-directed transgene expression and gene deletion in preclinical studies. Some of these increase function of the failing heart. Altering the expression of these pivotal regulators using gene transfer is now either being tested in clinical gene transfer trials, or soon will be. In this review, we summarize recent progress in cardiac gene transfer for clinical congestive heart failure.

  14. Current Concepts of Pelvic Congestion and Chronic Pelvic Pain

    Science.gov (United States)

    2001-01-01

    Chronic pelvic pain in women is a common and disabling illness caused by numerous organic pathologies usually accompanied by varying psychological dysfunctions. Many patients may receive misdiagnosis, misdirected therapies, or do not seek help at all. Pelvic congestion may be responsible for pain in patients without more common diseases, such as endometriosis and pelvic adhesions, among others. Our view of this condition is evolving. In the United States, this medical condition remains controversial. More recent research from the United Kingdom has caused a fresh look at the diagnosis and treatment of chronic pelvic pain produced by pelvic congestion. Potentially, many patients may benefit from a reconsideration of this approach. PMID:11394421

  15. Congestion in a city with a central bottleneck

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Palma, André de

    2010-01-01

    We consider dynamic congestion in an urban setting where trip origins are spatially distributed. All travelers must pass through a downtown bottleneck in order to reach their destination in the CBD. Each traveler chooses departure time to maximize general concave scheduling utility. At equilibrium......, travelers sort according to their distance to the destination. We construct a welfare maximizing tolling regime, which eliminates congestion. All travelers located beyond a critical distance from the CBD gain from tolling, even when toll revenues are not redistributed, while nearby travelers lose. We...

  16. Research and Implementation of Congestion Control Scheme in ForCES Router

    Directory of Open Access Journals (Sweden)

    Bangzhi Xiao

    2013-10-01

    Full Text Available With packet input rate rise ceaselessly, FoCES system will finally be congested. In order to solve this problem, aiming at the common local congestion and global congestion, this paper proposed a local congestion control strategy based on scheduling and a global congestion control mode based on the linkage between CE and FE. These two congestion control schemes can independently run inside the system, and also can operate simultaneously. Making that the forwarding rate, throughout and packet loss all have a great improvement in the FE end.

  17. Research on Urban Road Traffic Congestion Charging Based on Sustainable Development

    Science.gov (United States)

    Ye, Sun

    Traffic congestion is a major problem which bothers our urban traffic sustainable development at present. Congestion charging is an effective measure to alleviate urban traffic congestion. The paper first probes into several key issues such as the goal, the pricing, the scope, the method and the redistribution of congestion charging from theoretical angle. Then it introduces congestion charging practice in Singapore and London and draws conclusion and suggestion that traffic congestion charging should take scientific plan, support of public, public transportation development as the premise.

  18. 25 CFR 900.40 - When are Indian tribe or tribal organization management standards and management systems evaluated?

    Science.gov (United States)

    2010-04-01

    ... evaluated by an independent auditor through the annual single agency audit report that is required by the... Organization Management Systems General § 900.40 When are Indian tribe or tribal organization management...

  19. Evaluation of expected outcomes of nursing interventions to address the nursing diagnosis of fatigue among patients with congestive heart failure Evaluación de las intervenciones y de los resultados esperados para el diagnóstico de enfermería fatiga, en pacientes con insuficiencia cardiaca congestiva Avaliação das intervenções e dos resultados esperados para o diagnóstico de enfermagem fadiga, em portadores de insuficiência cardíaca

    Directory of Open Access Journals (Sweden)

    Cinthia Calsinski de Assis

    2007-09-01

    Full Text Available OBJECTIVE: To evaluate expected outcomes of nursing interventions to address the nursing diagnosis of fatigue. METHODS: A cross-sectional quasi-experimental design was used. The sample consisted of 30 coronary care unit in-patient with congestive heart failure and fatigue. A specific tool designed for this study was used to collect specific data on outcomes of nursing interventions to manage the nursing diagnosis of fatigue. RESULTS: Nursing interventions to manage patients' fatigue had positive outcomes. CONCLUSION: The use of the nursing process to identify the nursing diagnosis of fatigue, design and implement specific nursing interventions, and evaluate patient outcomes leads to quality nursing care.OBJETIVO: Evaluar los resultados alcanzados después de las intervenciones de enfermería para el diagnóstico de enfermería Fatiga. MÉTODOS Se trata de un estudio, cuasi-experimental, tiempo serie y transversal, realizado en un Hospital Universitario por medio de la implementación de intervenciones y evaluación diaria de los resultados en 30 pacientes con diagnóstico de insuficiencia cardiaca y de enfermería fatiga, internados en la Unidad de Cardiología y UCI Coronaria. Fue elaborado un instrumento de recolección de datos compuesto por intervenciones y resultados de enfermería. RESULTADOS: Fue observada buena evolución de todos los indicadores evaluados. Las intervenciones de enfermería alcanzaron de manera satisfactoria los resultados esperados. CONCLUSIÓN: Al sistematizar la asistencia de enfermería, alcanzamos resultados favorables en sus evidencias clínicas.OBJETIVO: Avaliar os resultados alcançados após intervenções de enfermagem para o diagnóstico de enfermagem Fadiga. MÉTODOS: Estudo, quase-experimental, tempo série e transversal, realizado em Hospital Universitário por meio da implementação de intervenções e avaliação diária dos resultados em 30 pacientes com diagnóstico de insuficiência cardíaca e de

  20. Further Thought on the Analysis of Urban Traffic Congestion Based on TDM: Taking Nanjing City as Example%基于TDM的城市交通拥挤分析的进一步思考——以南京市为例

    Institute of Scientific and Technical Information of China (English)

    苗滕

    2011-01-01

    Targeted at the exiting situation of urban traffic congestion, focusing on the essence of urban traffic congestion, based on the urban traffic congestion TDM analysis, and from the angle of long-term traffic management, this paper puts forward the control measures of urban traffic congestion.%本文针对城市交通拥挤现状,立足城市交通拥挤的实质,基于TDM城市交通拥挤分析,从中长期交通拥挤治理的角度,提出城市交通拥挤的治理措施.