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This project develops the environment for using the ATMIS simulation software developed under previous PATH projects (MOUs 39, 84, and 170) for real-time traffic simulation and scenario analysis with feedback from the real urban network. keywords: traffic simulation, databases, object-relation databases, dynasmart

This report provides an overview of the federally-sponsored Anaheim Advanced Traffic Control System Field Operations Test, and of the technical issues associated with the evaluation of SCOOT performance during this test. The primary FOT objective was the implementation and performance evaluation of adaptive traffic signal control technologies including an existing second generation approach, SCOOT, and a 1.5 generation control (1.5GC) approach under development. Also selected for implementation was a video traffic detection system (VTDS). The SCOOT evaluation was defined relative to existing, first generation UTCS-based control but using standard field detectorization rather than that normally associated with SCOOT. Furthermore, SCOOT was installed to operate in parallel to UTCS. The 1.5GC system was planned to be efficiently utilized to update baseline timing plans. The VTDS was planned for use as a low cost system detector for deployment in critical areas.Both SCOOT and the VTDS were implemented with some degree of success, with technical and institutional issues limiting expected performance. Technical issues that limited SCOOT performance included existing communication and controller systems of lower quality than anticipated. Corresponding institutional factors included inconsistent project management due to staff changes and delays due to contractual issues. Both SCOOT and a modified version of the VTDS are in current use in selected areas, with plans for system expansion.This evaluation report summarizes an introduction to the project, the evaluation objectives for Tasks A and B, and Task A of the three part evaluation project. Separate reports summarize Tasks B and C, assessment of institutional issues and the advanced Video Detection Systems, respectively

This Executive Summary provides an overview of the technical and institutional issues associated with the evaluation of the federally-sponsored Anaheim Advanced Traffic Control System Field Operations Test. The primary FOT objective was the implementation and performance evaluation of adaptive traffic signal control technologies including an existing second generation approach, SCOOT, and a 1.5 generation control (1.5GC) approach under development. Also selected for implementation was a video traffic detection system (VTDS).The SCOOT evaluation was defined relative to existing, first generation UTCS-based control but using standard field detectorization rather than that normally associated with SCOOT. Furthermore, SCOOT was installed to operate in parallel to UTCS. The 1.5GC system was planned to be efficiently utilized to update baseline timing plans. The VTDS was planned foruse as a low cost system detector for deployment in critical areas.Both SCOOT and the VTDS were implemented with some degree of success, with technical and institutional issues limiting expected performance. Technical issues which limited SCOOT performance included less than anticipated quality of existing communication and controller systems; corresponding institutional factors included inconsistent project management due to staff changes and delays due to contractual issues. Both SCOOT and a modified version of the VTDS are in current use in selected areas, with plans for system expansion.

This report provides an overview of the technical and institutional issues associated with the evaluation of the federally-sponsored Anaheim Advanced Traffic Control System Field Operations Test. The primary FOT objective was the implementation and performance evaluation of adaptive traffic signal control technologies including an existing second generation approach, SCOOT, and a 1.5 generation control (1.5GC) approach under development. Also selected for implementation was a video traffic detection system (VTDS). The SCOOT evaluation was defined relative to existing, first generation UTCS-based control but using standard field detectorization rather than that normally associated with SCOOT. Furthermore, SCOOT was installed to operate in parallel to UTCS. The 1.5GC system was planned to beefficiently utilized to update baseline timing plans. The VTDS was planned for use as a low cost system detector for deployment in critical areas.Both SCOOT and the VTDS were implemented with some degree of success, with technical and institutional issues limiting expected performance. Technical issues which limited SCOOT performance included less than anticipated quality of existing communication and controller systems; corresponding institutional factors included inconsistent project management due to staff changes and delays due to contractual issues. Both SCOOT and a modified version of the VTDS are in current use in selected areas, with plans for system expansion.This evaluation report summarizes Task B of the three part evaluation project. Separate reports summarize Task A and C, performance evaluations of the advanced traffic control technologies and the advanced Video Traffic Detection Systems, respectively.

This project will further adapt and enhance the previous research of relevance to event-based Advanced Traveler Information Systems (ATIS) and implement the algorithms for traffic management in Anaheim. The implementation involves the Caltrans-UCI ATMS research testbed framework at the UCI Institute of Transportation Studies, as well as the physical hardware available for communication to the city of Anaheim. The analytical algorithms proposed for use here include those for static and dynamic traffic assignment. and the modeling schemes used are the result of previous PATH and Testbed research projects on traffic simulation and driver behavioral response to information. The essential part of algorithmic research will be to adapt the network optimization algorithms to generate traffic rerouting plans, which involve aggregation of network paths and their translation to a format usable for changeable message signs existing in Anaheim. as well as other event-based information supply hardware. The implementation plan envisages a framework that is usable by the city for event-based congestion management, but its useis left to the city's decision. Key words: Advanced Traveler Information Systems, Optimal Routing, Dynamic Traffic Assignment, Changeable Message Signs

This report focuses on the DYNASMART simulation program presents a model that is capable of simulating large urban networks under various Advanced Traffic Management Systems (ATMS) and Advanced Traveler Information Systems (ATIS) strategies. It includes modules for driver responses to information and for capturing the dynamics of the network paths. The research also included the simulation study of a network in Orange County, California, where the benefits from candidate ATIS and ATMS strategies were evaluated. The DYNASMART model has evolved into a flexible tool that can be applied to evaluate information and control strategies in realistic urban networks in an efficient manner.

Sulforhodamine B (C27H30N2O7S2) (SRB) is a fluorescent dye commonly used for in-vitro cytotoxicity monitoring, which under standard conditions, does not undergo natural degradation and remains in water as such. We report on mesoporous In2S3 as an efficient photocatalytic agent for the degradation of this dye. Mesoporous In2S3 nanopowders were synthesized using a wet chemistry approach at a temperature of 30 °C. The synthesized nanopowders had preferential orientation along the (222) plane with an average crystallite size of ~ 4 nm. The pore size in the nanopowdered material was found to vary with the stoichiometry of the precursor solution. The photocatalytic degradation efficiency was found to vary with the pore size of the In2S3 nanopowder. The highest rate constant of 4.58 x 10-3 min-1 for SRB degradation was recorded for the sample with an average pore size of 1.79 nm. The mesoporous In2S3 demonstrates a degradation efficiency of ~ 91% under direct sunlight (~720 lux) and ~ 42.3% under the halogen light source (320 lux). [ABSTRACT FROM AUTHOR]

Sulforhodamine B (C27H30N2O7S2) (SRB) is a fluorescent dye commonly used for in-vitro cytotoxicity monitoring, which under standard conditions, does not undergo natural degradation and remains in water as such. We report on mesoporous In2S3 as an efficient photocatalytic agent for the degradation of this dye. Mesoporous In2S3 nanopowders were synthesized using a wet chemistry approach at a temperature of 30 °C. The synthesized nanopowders had preferential orientation along the (222) plane with an average crystallite size of ~ 4 nm. The pore size in the nanopowdered material was found to vary with the stoichiometry of the precursor solution. The photocatalytic degradation efficiency was found to vary with the pore size of the In2S3 nanopowder. The highest rate constant of 4.58 x 10-3 min-1 for SRB degradation was recorded for the sample with an average pore size of 1.79 nm. The mesoporous In2S3 demonstrates a degradation efficiency of ~ 91% under direct sunlight (~720 lux) and ~ 42.3% under the halogen light source (320 lux). [ABSTRACT FROM AUTHOR]

This paper takes a fresh look at the arguments against path-enumeration algorithms for the traffic assignment problem and provides the results of a gradient projection method. The motivation behind the research is the orders of magnitude improvement in the availability of computer storage over the last decade. Faster assignment algorithms are necessary for real-time traffic assignment under several of the proposed Advanced Traffic Management System (ATMS) strategies, and path-based solutions are preferred. Our results show that gradient projection converges in 1/10 iterations than the conventional Frank-Wolfe algorithm. The computation time improvement is of the same order for small networks, but reduces as the network size increases. We discuss the computer implementation issues carefully, and provide schemes to achieve a 10-fold speed-up for larger networks also. We have used the algorithm for networks of up to 2000 nodes on a typical computer work station, and we discuss certain data structures to save storage and solve the assignment problem for even a 5000 node network.

The design and implementation of Advanced Traveller Information Systems (ATIS) providing real-time enroute information to drivers should follow insightful analyses into the dynamics of driver decisions and the resulting traffic flow under information to prevent counter-intuitive and counter-productive results. An important yet often neglected aspect of this problem is the distribution of benefits both over the driver population and for different origins and destinations in the network. This paper presents modifications to and an application of DYNASMART (DYnamic Network Assignment Simulation Model for Advanced Road Telematics) for this problem. DYNASMART is a simulation framework for ATIS experiments which incorporates: 1) real-time traffic flow and control simulation, 2) dynamic network path processing, and 3) microscopic consideration of driver response to information. A boundedly-rational behavioral model is assumed for driver route-choice under non-prescriptive route information. The information strategies are based on multiple paths rather than a single shortest path. Initial paths of drivers were generated from dynamic equilibrium assignments using the CONTRAM program and used as input to DYNASMART. ATIS-equipped drivers change their paths based on a behavioral model (with stochastically assigned parameters) and provided information, while unequipped drivers change routes based on self-observation of traffic conditions. The application presented involves the evaluation of ATIS strategies to alleviate traffic congestion due to spectators leaving a major sports event at Anaheim Stadium. A dynamic traffic demand matrix was estimated from partial link-counts. Interesting insights are derived regarding the higher benefits from ATIS to drivers on congested parts of the network. Robustness of the benefits under various information supply strategies and behavioral scenarios are also discussed.

The focus of this research project was to develop a new simulation framework for analyzing traffic networks with Advanced Traveler Information Systems (ATIS) and/or Advanced Traffic Management Systems ( ATMS). The report describes the development of DYNASMART (DYnamic Network Assignment-Simulation Model for Advanced Road Telematics). The report is presented as follows: Chapter 1 discusses the simulation approach of DYNASMART and explains the traffic control features incorporated in it during the research. Chapter 2 discuss the simulations performed with a trial network with ATMS controls. Chapter 3 concentrates on the ATIS simulations on the Anaheim network. Results from the simulations of traffic management for special-events traffic from the Anaheim stadium are presented in Chapter 4, followed by overall conclusions.

This paper presents a unique integrated approach to meter placement and state estimation to ensure the network observability of active distribution systems. It includes observability checking, minimum measurement utilization, network state estimation, and trade-off evaluation between the number of real measurements used and the accuracy of the estimated state. In network parameter estimation, observability assessment is a preliminary task. It is handled by data analysis and filtering followed by calculation of the triangular factors of the singular, symmetric gain matrix using an algebraic method. Usually, to cover the deficiency of essential real measurements in distribution systems, huge numbers of virtual measurements are used. These pseudo measurements are calculated values, which are based on the network parameters, real measurements, and forecasted load/generation. Due to the application of a huge number of pseudo-measurements, large margins of error exists in the calculation phase. Therefore, there is still a high possibility of having large errors in estimated states, even though the network is classified as being observable. Hence, an integrated approach supported by forecasting is introduced in this work to overcome this critical issue. Finally, estimation of the trade-off in accuracy with respect to the number of real measurements used has been evaluated in order to justify the method’s practical application. The proposed method is applied to a Danish network, and the results are discussed.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.solener.2009.01.016 Byline: K.G. Deepa (a), R. Jayakrishnan (a), K.P. Vijayakumar (a), C. Sudha Kartha (a), V. Ganesan (b) Keywords: CuInSe.sub.2; Vacuum evaporation; Stoichiometry; Photoluminescence Abstract: CuInSe.sub.2 thin films were prepared using sequential vacuum evaporation of In, Se and Cu at moderately low substrate temperatures, avoiding any treatment using toxic H.sub.2Se gas. The samples were annealed at 400[degrees]C at a pressure of 10.sup.-5 mbar to form CuInSe.sub.2. Structural, optical, electrical, compositional and morphological characterizations were carried out on these films. We could obtain highly stoichiometric film, using this simple method, without opting for co-evaporation or high substrate temperature for deposition. Author Affiliation: (a) Thin Film Photovoltaic Division, Department of Physics, Cochin University of Science and Technology, Kochi-682022, India (b) UGC-DAE Consortium for Scientific Research, University Campus, Indore, India Article History: Received 31 August 2008; Revised 19 January 2009; Accepted 26 January 2009 Article Note: (miscellaneous) Communicated by: Associate Editor Takhir Razykov

A multi-faceted energy intensive technology that can be used for water disinfection and synthesis of electrolysed water (EW) is the need of the hour to achieve a sustainable post COVID 19 water management strategy. Direct sunlight driven processes are legislatively green technologies and hold the key in environmental sustenance. The development of a laboratory proto type reactor powered by a photovoltaic module for the treatment open source river water is described in this paper. This paper reports on the efficacy of the developed proto type technology for multipurpose application namely: (1) the production of Electrolysed water (EW) in a cost efficient manner using direct sunlight and (2) the removal of organic impurity from water using direct sunlight without the use of any photo catalyst or membrane. The prototype reactor utilizes chemical spray pyrolysis deposited highly photo-conducting indium sulphide thin films grown on fluorine doped tin oxide (F:SnO2) substrate (coated using chemical spray pyrolysis technique in-house) as the photo electrode. Dissolved organic matter arising in river water has distinctive fluorescence properties, and this research has utilized it to identify dissolved organic substances in both random samples and treated water. The work proves that photovoltaic module powered electrolytic reactors consisting of In2S3 electrodes can be used for treatment of river water. A diaphragm free, energy intensive route for the production of electrolysed water with the use of non-hazardous NaCl as the electrolyte has been demonstrated here. We conclude that In2S3 electrodes can be used for non-photo catalytic reduction of humic-derived impurities in river water. These results are also encouraging on the prospects of treating Nitrates present in the river water. The likes of techniques as described in this report that do not use photo catalyst or membranes may pave way for real time photovoltaic module powered floating reactors that can decontaminate water bodies on a large scale. The technique used by us demonstrates that a chlorine free route can be optimized for the synthesis of EW eliminating the production of large amounts of wastewater with high levels of biological oxygen demand (BOD). [ABSTRACT FROM AUTHOR]