The Convergence Scheme on Network Utility Maximization in Wireless Multicast Networks

With the ever-increasing wireless data application recently, considerable efforts have been focused on the designof distributed explicit rate scheme based on Network Utility Maximization (NUM) or wireless multi-hop meshnetworks. This paper describes a novel wireless multi-hop multicast flow control scheme for wireless meshnetworks via 802.11, which is based on the distributed self-turning Optimal Proportional plus Second-orderDifferential (OPSD) controller. The control scheme, which is located at the sources in the wireless multicastnetworks, can ensure short convergence time by regulating the transmission rate. We further analyze thetheoretical aspects of the proposed algorithm. Simulation results demonstrate the efficiency of the proposedscheme in terms of fast response time, low packet loss and error ration

Bike Lane Design: the Context Sensitive Approach

In these days of increasing congestion on roads, bicycles continue to provide a valuable contribution to mobility in Europe. Their relatively small size and low cost enable them to blend efficiently into in the traffic flow while needing less space compared to other vehicles. However, cyclists form one of the most vulnerable groups of road users. So the design of safe infrastructures for all travellers categories, included the cyclists, becomes a primary requirement. To obtain these results, a Context Sensitive Design approach is a very useful tool. In this way, in fact, it is possible to examine a project or existing road, reporting its crash potential and safety performances and detecting its deficiencies, taking into consideration communities and lands which it passes through. In this paper the authors, starting from results collected on a bike lane placed in Rimini, provide useful results for designers, construction and maintenance contractors, in order to obtain safe bike lanes

Quality of Service Oriented Access Point Selection Framework for Large Wi-Fi Networks

This paper addresses the problem of Access Point (AP) selection in large Wi-Fi networks. Unlike current solutions that rely on Received Signal Strength (RSS) to determine the best AP that could serve a wireless user’s request, we propose a novel framework that considers the Quality of Service (QoS) requirements of the user’s data flow. The proposed framework relies on a function reflecting the suitability of a Wi-Fi AP to satisfy the QoS requirements of the data flow. The framework takes advantage of the flexibility and centralised nature of Software Defined Networking (SDN). A performance comparison of this algorithm developed through an SDN-based simulator shows significant achievements against other state of the art solutions in terms of provided QoS and improved wireless network capacity

Disaster Med Public Health Prep

Objective:The objectives of this study were to: validate current capacity estimates for radiological emergency response by collecting time motion observations from stations that would be used for screening and decontaminating populations, and use collected times to evaluate potential impact on current throughput calculations.Methods:Time observations were collected at 11 functional radiation exercises across the country and aggregated for analysis for population monitoring activities, including contamination screening, decontamination, and registration. Collected times were compared to published estimates in current planning guidance, and evaluated to determine the suitability of using exercise observations to estimate throughput capacity.Results:2532-time observations were collected from 11 functional exercises. Of those, 2380 were validated and used for analysis. Contamination screening times varied greatly from current guidance, ranging from 19% below to 267% above existing estimates. Measurements indicate that capacity to perform contamination screening is significantly overestimated when using current estimates of service times and calculations when compared to observed aggregate service times.iConclusion:Aggregate service time data presented in this study can be used to yield a more realistic estimate of capacity to respond to a radiation event.CC999999/Intramural CDC HHSUnited States

Development of Optimal Control Strategies for Freeway Work Zone Operations

To improve traffic mobility and safety on highway segments plagued by work zone activities, transportation professionals in recent years have focused on exploring the potentials of using various merge and speed control strategies to regulate traffic flows. This study is focused on developing an advanced dynamic merge and variable speed limit controls for work zone applications, including an integration of both controls for best use of their strengths in maximizing throughputs and minimizing speed variance in traffic flows. With respect to the merge control, this study has developed an advanced dynamic late merge (DLM) control model and its operation algorithm, based on the optimized control thresholds that take into account the interactions between the speed, flow, and available work zone capacity. The proposed DLM control allows potential users to select the control variables and to determine their optimal thresholds in response to traffic flow dynamics. On regulating the approaching vehicle speeds, this study has developed a dynamic variable speed limit (VSL) control model and its operation algorithm. The proposed VSL system has adopted the maximization of work-zone throughput as its control objective with some embedded safety related constraints with such a system, one can optimize the sequence of transition speeds for approaching vehicles in the work zone, and dynamically adjusted the set of displayed speeds so as to effectively respond to potential demand variation. To best operate the DLM and VSL controls under various congested work zone conditions, this study has also explored the potential of integrating those two control strategies in work-zone operations. The logic of an integrated control is to facilitate the merging maneuvers and minimize potential collisions with the VSL during the DLM operation period, and to coordinate the sequence of VSM messages generated from both control algorithms. The numerical experiments have demonstrated that the integrated control can take full advantage of the strengths from both DLM and VSL controls, and offer the operational environment that is likely to yield a higher traffic throughput and lower speed variance than those operated independently

DETC2008-49526 PLATFORM STRATEGIES FOR A SUPPLIER IN THE AIRCRAFT ENGINE INDUSTRY

ABSTRACT The utilization of a platform strategy has become a competitive priority in many industries, most notably in the automotive industry. Naturally, many firms in other industries are adopting this strategy with different modifications and degrees of implementation. However, little research covers the application of platform development in a supplier and/or small batch production environment. The adaptation of a platform strategy in these settings, by a supplier in the aircraft engine industry, is the focal point of this paper. Based on platform development literature and the characteristics of the aircraft engine industry and the company studied advantages and hindrances for platform strategies have been ruled out. Interviews with involved people within the company studied have further clarified different perspectives on platforms and their possible utilization. Based on the analysis of collected information it is proposed that a possible platform strategy would include: a technology platform, incorporating general knowledge on core technology assets embodied in either humans, organizations, processes, information or methods; and a product platform, incorporating product specific elements that could be re-used when developing new components for a particular product line

Environ Int

Following a radiological or nuclear emergency, workers, responders and the public may be internally contaminated with radionuclides. Screening, monitoring and assessing any internal contamination and providing necessary medical treatment, especially when a large number of individuals are involved, is challenging. Experience gained and lessons learned from the management of previous incidents would help to identify gaps in knowledge and capabilities on preparedness for and response to radiation emergencies. In this paper, eight large-scale and five workplace radiological and nuclear incidents are reviewed cross 14 technical areas, under the broader topics of emergency preparedness, emergency response and recovery processes. The review findings suggest that 1) new strategies, algorithms and technologies are explored for rapid screening of large populations; 2) exposure assessment and dose estimation in emergency response and dose reconstruction in recovery process are supported by complementary sources of information, including 'citizen science'; 3) surge capacity for monitoring and dose assessment is coordinated through national and international laboratory networks; 4) evidence-based guidelines for medical management and follow-up of internal contamination are urgently needed; 5) mechanisms for international and regional access to medical countermeasures are investigated and implemented; 6) long-term health and medical follow up programs are designed and justified; and 7) capabilities and capacity developed for emergency response are sustained through adequate resource allocation, routine non-emergency use of technical skills in regular exercises, training, and continuous improvement.001/WHO_/World Health OrganizationInternational/CC999999/Intramural CDC HHSUnited States

Hydrodynamic Evaluation and Characterization of Capillary Channeled Polymer (C-CP) Fibers as a Stationary Phase in HPLC of Macromolecules

High Performance Liquid Chromatography (HPLC) is the most used analytical technique for the separation of samples in solution. HPLC of has progressed with successive use of new supports such as silica, polysaccharides, monoliths, and organic polymers. Although porous silica phases are very effective in small molecule separations, they suffer from certain drawbacks including pH stability, chemical robustness, high backpressure, and slow mass transfer for macromolecule separations. Thus, the most protein separations are carried out using nonporous, partially porous, and superficially porous phases to overcome mass transfer limitations. As a competing methodology, fiber based polymer support/stationary phases are also developed for protein separations. Capillary-channeled polymer (C-CP) fibers are being developed and characterized in the Marcus laboratory as a platform for variety of separations, predominantly for HPLC separation of macromolecules. C-CP fibers interdigitate to form a network-like structure when they are packed in a column that enables high fluid transport efficiency with low backpressure characteristics. This feature was successfully utilized for macromolecule separations with increased mass transfer characteristics at high linear velocities. In this study polypropylene (PP) C-CP fibers were utilized to evaluate the zone-broadening process of C-CP fiber columns, leading to the optimization of fiber diameter, column dimensions, and packing density (interstitial fraction) for analytical chromatographic separations. The optimized results were applied successfully for the separation of three-protein suite under reversed phase (RP) gradient conditions. Microbore PP C-CP columns were employed for rapid RP HPLC of proteins, evaluating the roles of column length, linear velocity, and radial compression on the separation performance. Nylon-6 C-CP fiber packed columns were characterized as substrates for the downstream processing of bio-macromolecules. An evaluation of adsorption and desorption characteristics of lysozyme on nylon-6 fibers have been investigated with the aim of determining frontal throughput and % yield. The results presented here show lot of promise in developing C-CP fibers as a combined support/stationary phase for bio-macromolecule separations