923 resultados para project work


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This year the development of our project can be divided into two main clearly different parts, on one hand the laboratory work, where the sampled ceramic individuals has been prepared and analyzed and the elaboration of the data obtained during the excavation of 2007 has been finished and, on the other hand, the field work developed at the archaeological site during this specific year (2008).In the mark of the analytical work a significant number of ceramic individuals (144) from the different stratigraphical units from various areas of the excavation of Termez and Tchinguiz Tepe sampled duringthe new and previous field works has been archaeometrically characterized. This specific material includedindividuals dated into the Hellenistic and Sassanian period, which has been confirmed by C14dating upon organic samples.At the same time, in the mark of the field work of 2008 the archaeological record, already started tobe under study during the excavation of 2007, has been completed and two new archaeological recordshave been registered on of which is located in the area of Tchinguiz Tepe. For the archeological studythe information of the previous geophysical prospecting has been indisputably taken into considerationand the same methodology has been applied to crosscheck the latter archaeological results.

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A previous study sponsored by the Smart Work Zone Deployment Initiative, “Feasibility of Visualization and Simulation Applications to Improve Work Zone Safety and Mobility,” demonstrated the feasibility of combining readily available, inexpensive software programs, such as SketchUp and Google Earth, with standard two-dimensional civil engineering design programs, such as MicroStation, to create animations of construction work zones. The animations reflect changes in work zone configurations as the project progresses, representing an opportunity to visually present complex information to drivers, construction workers, agency personnel, and the general public. The purpose of this study is to continue the work from the previous study to determine the added value and resource demands created by including more complex data, specifically traffic volume, movement, and vehicle type. This report describes the changes that were made to the simulation, including incorporating additional data and converting the simulation from a desktop application to a web application.

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A laboratory study has been conducted with two aims in mind. The first goal was to develop a description of how a cutting edge scrapes ice from the road surface. The second goal was to investigate the extent, if any, to which serrated blades were better than un-serrated or "classical" blades at ice removal. The tests were conducted in the Ice Research Laboratory at the Iowa Institute of Hydraulic Research of the University of Iowa. A specialized testing machine, with a hydraulic ram capable of attaining scraping velocities of up to 30 m.p.h. was used in the testing. In order to determine the ice scraping process, the effects of scraping velocity, ice thickness, and blade geometry on the ice scraping forces were determined. Higher ice thickness lead to greater ice chipping (as opposed to pulverization at lower thicknesses) and thus lower loads. S~milabr ehavior was observed at higher velocities. The study of blade geometry included the effect of rake angle, clearance angle, and flat width. The latter were found to be particularly important in developing a clear picture of the scraping process. As clearance angle decreases and flat width increases, the scraping loads show a marked increase, due to the need to re-compress pulverized ice fragments. The effect of serrations was to decrease the scraping forces. However, for the coarsest serrated blades (with the widest teeth and gaps) the quantity of ice removed was significantly less than for a classical blade. Finer serrations appear to be able to match the ice removal of classical blades at lower scraping loads. Thus, one of the recommendations of this study is to examine the use of serrated blades in the field. Preliminary work (by Nixon and Potter, 1996) suggests such work will be fruitful. A second and perhaps more challenging result of the study is that chipping of ice is more preferable to pulverization of the ice. How such chipping can be forced to occur is at present an open question.

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The objective of this project was to promote and facilitate analysis and evaluation of the impacts of road construction activities in Smart Work Zone Deployment Initiative (SWZDI) states. The two primary objectives of this project were to assess urban freeway work-zone impacts through use of remote monitoring devices, such as radar-based traffic sensors, traffic cameras, and traffic signal loop detectors, and evaluate the effectiveness of using these devices for such a purpose. Two high-volume suburban freeway work zones, located on Interstate 35/80 (I-35/I-80) through the Des Moines, Iowa metropolitan area, were evaluated at the request of the Iowa Department of Transportation (DOT).

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Iowa faces a growing crisis in providing an adequate number of direct care workers for its again population. Direct care workers caring for the aging and disabled population are among those in our work force with the lowest wages and lack of access to health insurance. A survey of direct care workers conducted by the Iowa Caregivers Association in June of 2066 indicated that benefits ranked second only to wages in the reasons for job-hoping. A study of the direct care workforce in Vermont healthy insurance, ranked second only to wages, as important to attracting and keeping direct care workers.

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90Y-labelled radiopharmaceuticals offer promising prospects for radionuclide therapies of tumours, e.g. radioimmunotherapies (RIT), (EANM, 2007), peptide receptor radiotherapies (PRRT), (Otte et al., 1998), and selective internal radiotherapies (SIRT), (Salem and Thurston, 2006). 90Y, an almost pure high-energy beta radiation emitter (Eβ,max = 2.28 MeV), is a favourable radionuclide for therapeutic purposes. However, when preparing and performing these therapies, high activities of 90Y (>1 GBq) are to be manipulated and technicians, physicians and nurses may receive high skin exposures to the hands. If radiation protection standards are low, the exposure of staff can exceed the annual skin dose limit of 500 mSv. Within a particular work package (WP4) of the ORAMED project, comprehensive measurements in nuclear medicine departments of several hospitals in 6 European countries were carried out. The study focussed on 90Y-labelled substances such as Zevalin® and DOTATOC to achieve a representative database on staff exposure. This paper summarises the most important results and conclusions for individual monitoring of skin exposure of staff.

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Incentive/disincentive clauses (I/D) are designed to award payments to contractors if they complete work ahead of schedule and to deduct payments if they exceed the completion time. A previously unanswered question is, “Did the costs of the actual work zone impacts that were avoided justify the incentives paid?” This report answers that question affirmatively based on an evaluation of 20 I/D projects in Missouri from 2008 to 2011. Road user costs (RUC) were used to quantify work zone impacts and included travel delays, vehicle operating costs, and crash costs. These were computed using work zone traffic conditions for partial-closure projects and detour volumes and routes for full-closure projects. Conditions during construction were compared to after construction. Crash costs were computed using Highway Safety Manual methodology. Safety Performance Functions produced annual crash frequencies that were translated into crash cost savings. In considering an average project, the percentage of RUC savings was around 13% of the total contract amount, or $444,389 of $3,464,620. The net RUC savings produced was around $7.2 million after subtracting the approximately $1.7 million paid in incentives. In other words, for every dollar paid in incentives, approximately 5.3 dollars of RUC savings resulted. I/D provisions were very successful in saving RUC for projects with full-closure, projects in urban areas, and emergency projects. Rural, non-emergency projects successfully saved RUC but not at the same level as other projects. The I/D contracts were also compared to all Missouri Department of Transportation contracts for the same time period. The results show that I/D projects had a higher on-time completion percentage and a higher number of bids per call than average projects. But I/D projects resulted in 4.52% higher deviation from programmed costs and possibly more changes made after the award. A survey of state transportation departments and contractors showed that both agreed to the same issues that affect the success of I/D contracts. Legal analysis suggests that liquidated damages is preferred to disincentives, since enforceability of disincentives may be an issue. Overall, in terms of work zone impact mitigation, I/D contracts are very effective at a relatively low cost.

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Supplementary cementitious materials (SCM) have become common parts of modern concrete practice. The blending of two or three cementitious materials to optimize durability, strength, or economics provides owners, engineers, materials suppliers, and contractors with substantial advantages over mixtures containing only portland cement. However, these advances in concrete technology and engineering have not always been adequately captured in specifications for concrete. Users need specific guidance to assist them in defining the performance requirements for a concrete application and the selection of optimal proportions of the cementitious materials needed to produce the required durable concrete. The fact that blended cements are currently available in many regions increases options for mixtures and thus can complicate the selection process. Both Portland and blended cements have already been optimized by the manufacturer to provide specific properties (such as setting time, shrinkage, and strength gain). The addition of SCMs (as binary, ternary, or even more complex mixtures) can alter these properties, and therefore has the potential to impact the overall performance and applications of concrete. This report is the final of a series of publications describing a project aimed at addressing effective use of ternary systems. The work was conducted in several stages and individual reports have been published at the end of each stage.

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Highway construction is among the most dangerous industries in the US. Internal traffic control design, along with how construction equipment and vehicles interact with the traveling public, have a significant effect on how safe a highway construction work zone can be. An integrated approach was taken to research work-zone safety issues and mobility, including input from many personnel, ranging from roadway designers to construction laborers and equipment operators. The research team analyzed crash data from Iowa work-zone incident reports and Occupational Safety and Health Administration data for the industry in conjunction with the results of personal interviews, a targeted work-zone ingress and egress survey, and a work-zone pilot project.

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The Capitol grounds have been evolving through planned and unplanned actions for more than 150 years. The 1857 Constitutio established Des Moines as the capital. The commissioners appointed to choose a site decided on land donated by Wilson Alexander Scott and Harrison Lyon. Located on the east side of the Des Moines River, on a gently rising hill, the site for the Iowa State Capitol began with fewer than 10 acres. The Old Brick Capitol was built in the center of that 10-acre plot, and the area to the north was used as a public park until work began on the present day Capitol. In 1884, the two-year process of moving from the Old Brick Capitol to the new Capitol began. The state commissioned John Weidenman to design the first formal decoration of the grounds. Weidenman’s plans for the west approach to the Capitol included planting statues, and walkways. The State held some additional land but not necessarily land adjacent to the Capitol. In 1909, legislation was passed, and in 1913, the Thirty-Fifth General Assembly enacted controversial legislation to acquire additional land. A commission was formed to locate a purposed monument honoring the long-serving U.S. Senator William B. Allison. E.L. Masqueray was hired as the architect expert focusing on the selection of a proper site for the proposed Allison Memorial. Masqueray’s plan detailed the placement of buildings and potential monuments. Growth of the Capitol Complex, as known today, began.

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In the last decade, Intelligent Transportation Systems (ITS) have increasingly been deployed in work zones by state departments of transportation. Also known as smart work zone systems they improve traffic operations and safety by providing real-time information to travelers, monitoring traffic conditions, and managing incidents. Although there have been numerous ITS deployments in work zones, a framework for evaluating the effectiveness of these deployments does not exist. To justify the continued development and implementation of smart work zone systems, this study developed a framework to determine ITS effectiveness for specific work zone projects. The framework recommends using one or more of five performance measures: diversion rate, delay time, queue length, crash frequency, and speed. The monetary benefits and costs of ITS deployment in a work zone can then be computed using the performance measure values. Such ITS computations include additional considerations that are typically not present in standard benefit-cost computations. The proposed framework will allow for consistency in performance measures across different ITS studies thus allowing for comparisons across studies or for meta analysis. In addition, guidance on the circumstances under which ITS deployment is recommended for a work zone is provided. The framework was illustrated using two case studies: one urban work zone on I-70 and one rural work zone on I-44, in Missouri. The goals of the two ITS deployments were different – the I-70 ITS deployment was targeted at improving mobility whereas the I-44 deployment was targeted at improving safety. For the I-70 site, only permanent ITS equipment that was already in place was used for the project and no temporary ITS equipment was deployed. The permanent DMS equipment serves multiple purposes, and it is arguable whether that cost should be attributed to the work zone project. The data collection effort for the I-70 site was very significant as portable surveillance captured the actual diversion flows to alternative routes. The benefit-cost ratio for the I-70 site was 2.1 to 1 if adjusted equipment costs were included and 6.9 to 1 without equipment costs. The safety-focused I-44 ITS deployment had an estimated benefit-cost ratio of 3.2 to 1.

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This year the development of our project can be divided into two main clearly different parts, on one hand the laboratory work, where the sampled ceramic individuals has been prepared and analyzed and the elaboration of the data obtained during the excavation of 2007 has been finished and, on the other hand, the field work developed at the archaeological site during this specific year (2008).In the mark of the analytical work a significant number of ceramic individuals (144) from the different stratigraphical units from various areas of the excavation of Termez and Tchinguiz Tepe sampled duringthe new and previous field works has been archaeometrically characterized. This specific material includedindividuals dated into the Hellenistic and Sassanian period, which has been confirmed by C14dating upon organic samples.At the same time, in the mark of the field work of 2008 the archaeological record, already started tobe under study during the excavation of 2007, has been completed and two new archaeological recordshave been registered on of which is located in the area of Tchinguiz Tepe. For the archeological studythe information of the previous geophysical prospecting has been indisputably taken into considerationand the same methodology has been applied to crosscheck the latter archaeological results.

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The purpose of this project was to determine the optimal hole pattern needed for undersealing work, and also to determine if it is feasible to underseal a roadway with existing longitudinal subdrains without plugging the subdrain system. At the test site the hole pattern had little effect on the grout distribution. It was found that the hole pattern, to be effective, must locate existing voids and that holes must extend at least 2 in. (5 cm) below the underside of the pavement. It appeared that pavements can be undersealed without significant damage to the existing subdrains, but special care is needed to assure that excess grout is not injected into the drainage system. Recommendations are made concerning the hole pattern, grout efflux time, and procedures for minimizing the risk of plugging the subdrains with grout.

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This document contains a discussion of the reasons why the project did not succeed. A detailed discussion of the steps taken by the Iowa Department of Transportation to make the experiment work are contained in this document, along with recommendations for future projects.

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This report describes a new approach to the problem of scheduling highway construction type projects. The technique can accurately model linear activities and identify the controlling activity path on a linear schedule. Current scheduling practices are unable to accomplish these two tasks with any accuracy for linear activities, leaving planners and manager suspicious of the information they provide. Basic linear scheduling is not a new technique, and many attempts have been made to apply it to various types of work in the past. However, the technique has never been widely used because of the lack of an analytical approach to activity relationships and development of an analytical approach to determining controlling activities. The Linear Scheduling Model (LSM) developed in this report, completes the linear scheduling technique by adding to linear scheduling all of the analytical capabilities, including computer applications, present in CPM scheduling today. The LSM has tremendous potential, and will likely have a significant impact on the way linear construction is scheduled in the future.