Traditionally, optimization of diamond interchange timings has been done with PASSER III for standard and special diamond phasing sequences. PASSER III is limited because it is designed for undersaturated conditions. It applies vertical stacking of queues and is not capable of modeling queue spillback conditions in its current form. This deficiency is addressed by the arterial signal coordination software (ASCS), whose capabilities in timing diamond interchanges in under-saturated and oversaturated conditions are presented here. ASCS consists of three modules: ( a) input module, a user interface through which volume and geometry inputs can be provided to the program; ( b) optimization module, a genetic algorithm-based optimization routine that can optimize signal timings; and ( c) analysis module, which consists of a bandwidth analysis routine and a delay analysis routine (DAR). The DAR is a mesoscopic simulator that applies a second-by-second analysis of flows for modeling flows accurately. DAR applies horizontal stacking of queues and shock wave analysis to estimate the performance of traffic operations. Validation of ASCS for oversaturated arterial links against PASSER III and CORSIM was conducted. The results indicate that delay and throughput estimation in ASCS are realistic. The genetic algorithm-based optimization routine in ASCS was applied to estimate diamond interchange timings for three scenarios. Where queue spillback occurred, ASCS clearly outperformed PASSER III. ASCS produced near-optimal results for all scenarios studied.
Obscure gastrointestinal bleeding (GIB) in patients with continuous-flow left ventricular assist devices (CF-LVAD) is common. Capsule endoscopy (CE) can be used in the diagnosis of obscure GIB. Safety and outcomes of CE in patients with CF-LVAD are unknown. The aim is to define the safety and outcomes of CE in this population. Paitents with CF-LVAD undergoing CE at a single center between 2007 and 2014 were retrospectively reviewed. Thirty-four CE studies were performed. Positive CE occurred in 19 studies. No clinically significant cardiac events occurred. Medical intervention was the most common management strategy. Rebleeding after CE occurred in 10 patients. Patients with active bleeding or lesions such as arteriovenous malformations (AVM) incurred a higher risk of rebleeding, transfusion, and repeated endoscopy. CE is safe in patients with CF-LVAD. The risk of rebleeding was more common in patients with active bleeding or AVM lesions although this result did not reach statistical significance.
Guidelines were developed for designing freeway on-ramps in which ramp metering is envisioned. More specifically, design issues were probed for ramps in which the ramp meter utilizes a queue detector to identify and prevent a queue of vehicles from blocking the upstream intersection. First, the benefits of ramp metering operation were delineated, and general design considerations were then drawn up. Finally, design criteria were developed for three distance requirements for freeway on-ramps: safe stopping distance, storage distance, and acceleration distance.
The objective of this study was to develop a methodology for assessing the impact of road construction that could be used to (a) predict the network-level impact of road construction projects, (b) identify critical roadway segments and corridors in which the impacts of construction are expected to be the most severe, and (c) compare alternative construction scenarios and schedules. Dynamic traffic assignment formed the basis of an approach to assess the regional impact of road construction and compare alternative construction schedule scenarios. The application of the model was illustrated with the use of a hypothetical case of two road construction projects in the roadway system of El Paso, Texas.
Helicobacter pylori infection is strongly associated with low-grade gastric lymphoma, commonly known as mucosa-associated lymphoid tissue (MALT) lymphoma. H. pylori eradication leads to complete remission in 80% of early stage MALT lymphomas. The treatment for early stage H. pylori-negative gastric MALT lymphoma is evolving. Rituximab, a chimeric anti-CD20 antibody, has shown response rates of approximately 50% with minimal toxicity in patients with B-cell non-Hodgkin lymphoma. We describe herein the clinical, endoscopic, and histologic features of a patient with H. pylori-negative gastric MALT lymphoma treated successfully with rituximab.
Abstract-This paper investigates the resource allocation problem for a type of workflows in pervasive computing. These workflows are abstracted from the enterprise-level applications in the business or commerce area. The activities in these workflows require not only computing resources, but also human resources. Human involvement introduces additional security concerns. When we plan/allocate resource capacities, we often assume that when a task is allocated to a resource, the resource will accept the task and start the execution once the processor becomes available. However, the security policies impose further constraints on task executions, and therefore may affect both application-and system-oriented performance. Authorization is a important aspect in security. This paper investigates the issue of allocating resources for running workflows under the role-based authorization control, which is one of the most popular authorization mechanisms. By taking into account the authorization constraints, the resource allocation strategies are developed in this paper for both human resources and computing resources. In the allocation strategy for human resources, the optimization equation is constructed subject to the constraint of the budget available to hire human resources. Then the optimization equation is solved to obtain the number of human resources allocated to each authorization role. The allocation strategy for computing resources calculates not only the number of computing resources, but also the proportion of processing capacity in each resource allocated to serve the tasks assuming each role. The simulation experiments have been conducted to verify the effectiveness of the developed allocation strategies. The experimental results show that the allocation strategy developed in this paper outperforms the traditional allocation strategies, which do not consider authorization constraints, in terms of both average response time and resource utilization.
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