905 resultados para Development of large software systems,


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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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This report is on state-of-the-art research efforts specific to infrastructure inventory/data collection with sign inventory as a case study. The development of an agency-wide sign inventory is based on feature inventory and location information. Specific to location, a quick and simple location acquisition tool is critical to tying assets to an accurate location-referencing system. This research effort provides a contrast between legacy referencing systems (route and milepost) and global positioning system- (GPS-) based techniques (latitude and longitude) integrated into a geographic information system (GIS) database. A summary comparison of field accuracies using a variety of consumer grade devices is also provided. This research, and the data collection tools developed, are critical in supporting the Iowa Department of Transportation (DOT) Statewide Sign Management System development effort. For the last two years, a Task Force has embarked on a comprehensive effort to develop a sign management system to improve sign quality, as well as to manage all aspects of signage, from request, ordering, fabricating, installing, maintaining, and ultimately removing, and to provide the ability to budget for these key assets on a statewide basis. This effort supported the development of a sign inventory tool and is the beginning of the development of a sign management system to support the Iowa DOT efforts in the consistent, cost effective, and objective decision making process when it comes to signs and their maintenance.

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The Iowa Department of Transportation (Iowa DOT) currently performs wetland mitigation on a project-by-project basis. At the same time, other agencies like the Iowa Department of Natural Resources and Natural Resource Conservation Service are performing wetland restoration projects, and counties and cities may be mitigating wetland losses as well. This project examined the feasibility of developing cooperative wetland mitigation projects in order to utilize state and local resources more efficiently to benefit both Iowa and local communities. The project accomplished the following objectives: (1) Identified and characterized cooperative wetland mitigation programs nationwide; (2) Developed a needs assessment through a survey of state, county, and large city agencies in Iowa to describe wetland mitigation programs and determine challenges with mitigation and program improvements, including long-term risks associated with maintenance and monitoring programs; (3) Surveyed state, county, and city agencies and organizations to identify resources available for developing cooperative mitigation projects and procedures; (4) Developed a conceptual framework for cooperative wetland mitigation.

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The following paper introduces a new approach to the analysis of offensive game in football. Therefore, the main aim of this study was to create an instrument for collecting information for the analysis of offensive action and interactions game. The observation instrument that was used to accomplish the main objective of this work consists of a combination of format fields (FC) and systems of categories (SC). This methodology is a particular strategy of the scientific method that has as an objective to analyse the perceptible behaviour that occurs in habitual contexts, allowing them to be formally recorded and quantified and using an ad hoc instrument in order to obtain a behaviour systematic registration that, since they have been transformed in quantitative data with the necessary reliability and validity determined level, will allow analysis of the relations between these behaviours. The codifications undertaken to date in various games of football have shown that it serves the purposes for which it was developed, allowing more research into the offensive game methods in football.

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Since 1978 the concept of longitudinal edge drains along Iowa primary and Interstate highways has been accepted as a cost-effective way of prolonging pavement life. Edge-drain installations have increased over the years, reaching a total of nearly 3,000 mi by 1989. With so many miles of edge drain installed, the development of a system for inspection and evaluation of the drains became essential. Equipment was purchased to evaluate 4-in.-diameter and geocomposite edge drains. Initial evaluations at various sites supported the need for a postconstruction inspection program to ensure that edge-drain installations were in accord with plans and specifications. Information disclosed by video inspections in edge drains and in culverts was compiled on videotape to be used as an informative tool for personnel in the design, construction, and maintenance departments. Video evaluations have influenced changes in maintenance, design, and construction inspection for highway drainage systems in Iowa.

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The results of several large multicenter CMR studies were reported in 2012, thus, constantly corroborating the evidence on CMR performance. In this review, we present results of the MR-IMPACT programme and the CE-MARC study, which demonstrated the superiority of perfusion-CMR over gated SPECT for the workup of suspected CAD, the currently available data from the European CMR registry, comprising almost 30,000 patients from 57 participating centers in 15 European countries, and finally, the results of the Advisa-MRI study, which documented the safety of a MRI-compatible pacemaker system. These large trials and others set the basis for the recommendations in the new European guidelines on heart failure to use CMR as a first line method if echocardiographic quality is inadequate or the etiology of heart failure is unclear.

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The murine gut epithelium contains a large population of thymus-derived intraepithelial lymphocytes (IELs), including both conventional CD4(+) and CD8alphabeta(+) T cells (expressing T-cell receptor alphabeta [TCRalphabeta]) and unconventional CD8alphaalpha(+) T cells (expressing either TCRalphabeta or TCRgammadelta). Whereas conventional IELs are widely accepted to arise from recirculation of activated CD4(+) and CD8alphabeta(+) T cells from the secondary lymphoid organs to the gut, the origin and developmental pathway of unconventional CD8alphaalpha IELs remain controversial. We show here that CD4-Cre-mediated inactivation of c-Myc, a broadly expressed transcription factor with a wide range of biologic activities, selectively impairs the development of CD8alphaalpha TCRalphabeta IELs. In the absence of c-Myc, CD4(-) CD8(-) TCRalphabeta(+) thymic precursors of CD8alphaalpha TCRalphabeta IELs are present but fail to develop on adoptive transfer in immunoincompetent hosts. Residual c-Myc-deficient CD8alphaalpha TCRalphabeta IEL display reduced proliferation and increased apoptosis, which correlate with significantly decreased expression of interleukin-15 receptor subunits and lower levels of the antiapoptotic protein Bcl-2. Transgenic overexpression of human BCL-2 resulted in a pronounced rescue of CD8alphaalpha TCRalphabeta IEL in c-Myc-deficient mice. Taken together, our data support a model in which c-Myc controls the development of CD8alphaalpha TCRalphabeta IELs from thymic precursors by regulating interleukin-15 receptor expression and consequently Bcl-2-dependent survival.

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Often, road construction causes the need to create a work zone. In these scenarios, portable concrete barriers (PCBs) are typically installed to shield workers and equipment from errant vehicles as well as prevent motorists from striking other roadside hazards. For an existing W-beam guardrail system installed adjacent to the roadway and near the work zone, guardrail sections are removed in order to place the portable concrete barrier system. The focus of this research study was to develop a proper stiffness transition between W-beam guardrail and portable concrete barrier systems. This research effort was accomplished through development and refinement of design concepts using computer simulation with LS-DYNA. Several design concepts were simulated, and design metrics were used to evaluate and refine each concept. These concepts were then analyzed and ranked based on feasibility, likelihood of success, and ease of installation. The rankings were presented to the Technical Advisory Committee (TAC) for selection of a preferred design alternative. Next, a Critical Impact Point (CIP) study was conducted, while additional analyses were performed to determine the critical attachment location and a reduced installation length for the portable concrete barriers. Finally, an additional simulation effort was conducted in order to evaluate the safety performance of the transition system under reverse-direction impact scenarios as well as to select the CIP. Recommendations were also provided for conducting a Phase II study and evaluating the nested Midwest Guardrail System (MGS) configuration using three Test Level 3 (TL-3) full-scale crash tests according to the criteria provided in the Manual for Assessing Safety Hardware, as published by the American Association of Safety Highway and Transportation Officials (AASHTO).

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This project utilized information from ground penetrating radar (GPR) and visual inspection via the pavement profile scanner (PPS) in proof-of-concept trials. GPR tests were carried out on a variety of portland cement concrete pavements and laboratory concrete specimens. Results indicated that the higher frequency GPR antennas were capable of detecting subsurface distress in two of the three pavement sites investigated. However, the GPR systems failed to detect distress in one pavement site that exhibited extensive cracking. Laboratory experiments indicated that moisture conditions in the cracked pavement probably explain the failure. Accurate surveys need to account for moisture in the pavement slab. Importantly, however, once the pavement site exhibits severe surface cracking, there is little need for GPR, which is primarily used to detect distress that is not observed visually. Two visual inspections were also conducted for this study by personnel from Mandli Communications, Inc., and the Iowa Department of Transportation (DOT). The surveys were conducted using an Iowa DOT video log van that Mandli had fitted with additional equipment. The first survey was an extended demonstration of the PPS system. The second survey utilized the PPS with a downward imaging system that provided high-resolution pavement images. Experimental difficulties occurred during both studies; however, enough information was extracted to consider both surveys successful in identifying pavement surface distress. The results obtained from both GPR testing and visual inspections were helpful in identifying sites that exhibited materials-related distress, and both were considered to have passed the proof-of-concept trials. However, neither method can currently diagnose materials-related distress. Both techniques only detected the symptoms of materials-related distress; the actual diagnosis still relied on coring and subsequent petrographic examination. Both technologies are currently in rapid development, and the limitations may be overcome as the technologies advance and mature.

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Recent reports indicate that of the over 25,000 bridges in Iowa, slightly over 7,000 (29%) are either structurally deficient or functionally obsolete. While many of these bridges may be strengthened or rehabilitated, some simply need to be replaced. Before implementing one of these options, one should consider performing a diagnostic load test on the structure to more accurately assess its load carrying capacity. Frequently, diagnostic load tests reveal strength and serviceability characteristics that exceed the predicted codified parameters. Usually, codified parameters are very conservative in predicting lateral load distribution characteristics and the influence of other structural attributes. As a result, the predicted rating factors are typically conservative. In cases where theoretical calculations show a structural deficiency, it may be very beneficial to apply a "tool" that utilizes a more accurate theoretical model which incorporates field-test data. At a minimum, this approach results in more accurate load ratings and many times results in increased rating factors. Bridge Diagnostics, Inc. (BDI) developed hardware and software that are specially designed for performing bridge ratings based on data obtained from physical testing. To evaluate the BDI system, the research team performed diagnostic load tests on seven "typical" bridge structures: three steel-girder bridges with concrete decks, two concrete slab bridges, and two steel-girder bridges with timber decks. In addition, a steel-girder bridge with a concrete deck previously tested and modeled by BDI was investigated for model verification purposes. The tests were performed by attaching strain transducers on the bridges at critical locations to measure strains resulting from truck loading positioned at various locations on the bridge. The field test results were used to develop and validate analytical rating models. Based on the experimental and analytical results, it was determined that bridge tests could be conducted relatively easy, that accurate models could be generated with the BDI software, and that the load ratings, in general, were greater than the ratings, obtained using the codified LFD Method (according to AASHTO Standard Specifications for Highway Bridges).

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Currently, individuals including designers, contractors, and owners learn about the project requirements by studying a combination of paper and electronic copies of the construction documents including the drawings, specifications (standard and supplemental), road and bridge standard drawings, design criteria, contracts, addenda, and change orders. This can be a tedious process since one needs to go back and forth between the various documents (paper or electronic) to obtain information about the entire project. Object-oriented computer-aided design (OO-CAD) is an innovative technology that can bring a change to this process by graphical portrayal of information. OO-CAD allows users to point and click on portions of an object-oriented drawing that are then linked to relevant databases of information (e.g., specifications, procurement status, and shop drawings). The vision of this study is to turn paper-based design standards and construction specifications into an object-oriented design and specification (OODAS) system or a visual electronic reference library (ERL). Individuals can use the system through a handheld wireless book-size laptop that includes all of the necessary software for operating in a 3D environment. All parties involved in transportation projects can access all of the standards and requirements simultaneously using a 3D graphical interface. By using this system, users will have all of the design elements and all of the specifications readily available without concerns of omissions. A prototype object-oriented model was created and demonstrated to potential users representing counties, cities, and the state. Findings suggest that a system like this could improve productivity to find information by as much as 75% and provide a greater sense of confidence that all relevant information had been identified. It was also apparent that this system would be used by more people in construction than in design. There was also concern related to the cost to develop and maintain the complete system. The future direction should focus on a project-based system that can help the contractors and DOT inspectors find information (e.g., road standards, specifications, instructional memorandums) more rapidly as it pertains to a specific project.

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The main function of a roadway culvert is to effectively convey drainage flow during normal and extreme hydrologic conditions. This function is often impaired due to the sedimentation blockage of the culvert. This research sought to understand the mechanics of sedimentation process at multi-box culverts, and develop self-cleaning systems that flush out sediment deposits using the power of drainage flows. The research entailed field observations, laboratory experiments, and numerical simulations. The specific role of each of these investigative tools is summarized below: a) The field observations were aimed at understanding typical sedimentation patterns and their dependence on culvert geometry and hydrodynamic conditions during normal and extreme hydrologic events. b) The laboratory experiments were used for modeling sedimentation process observed insitu and for testing alternative self-cleaning concepts applied to culverts. The major tasks for the initial laboratory model study were to accurately replicate the culvert performance curves and the dynamics of sedimentation process, and to provide benchmark data for numerical simulation validation. c) The numerical simulations enhanced the understanding of the sedimentation processes and aided in testing flow cases complementary to those conducted in the model reducing the number of (more expensive) tests to be conducted in the laboratory. Using the findings acquired from the laboratory and simulation works, self-cleaning culvert concepts were developed and tested for a range of flow conditions. The screening of the alternative concepts was made through experimental studies in a 1:20 scale model guided by numerical simulations. To ensure the designs are effective, performance studies were finally conducted in a 1:20 hydraulic model using the most promising design alternatives to make sure that the proposed systems operate satisfactory under closer to natural scale conditions.

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Stage-discharge relations constitute a viable, alternative technique for estimating accurately flow for ungaged sites. In this research, we have utilized pressure transducers and Large Scale Particle Image Velocimetry techniques to develop stage-discharge relations at eleven sites in the Hungry Canyon Area (HCA) of southwestern Iowa under different hydrologic conditions. We have employed these data to calibrate and verify an established hydrologic model and then we have used this model to provide a stage discharge relation for different hydrologic conditions (i.e. rating curves). The benefits of the project are numerous including that the discharge data will be used for a number of purposes, including operational decision making in the HCA about the design of water-control and conveyance structures, input for hydraulic and hydrologic models, and calculation of sediment and other water quality constituents transport and “loads”, and for decision making. This project has also pointed out the difficulties in measuring flows in ungaged streams with ice jams, steep banks, erodible beds, and floating debris.

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The appearance of immunoreactive alpha-melanotropin (alpha-MSH) and adrenocorticotropin (ACTH) during development was studied in 3 areas of the rat brain--cerebral hemispheres, midbrain and hindbrain--from embryonic day (ED) 13-14 until day 21 postnatally. The alpha-MSH content in vivo was always highest in the midbrain; a peak content at birth was followed by a transient decline and a later, higher plateau from postnatal day 7 onwards. The alpha-MSH content in the cerebral hemispheres rose progressively after birth reaching a peak at day 21. Values in the hindbrain rose at day 3 and changed relatively sue taken at ED 15-16 showed a gradual increase in alpha-MSH content over the 20 days. The alpha-MSH content of hindbrain cultures remained at constant low levels, while no alpha-MSH was detectable in cerebral hemisphere cultures. ACTH appeared in vivo earlier than alpha-MSH and was detectable in embryonic brains at ED 13-14. A transient rise was seen at ED 17-18 and major peaks at birth, day 2 and day 3, in the midbrain, hemispheres and hindbrain, respectively. In vitro, the ACTH content increased in all brain regions during the first 5 days in culture and showed no further change thereafter. Comparisons of the in vivo and in vitro development of alpha-MSH and ACTH demonstrate that (i) these two peptide systems are independent in respect to their localization and time of appearance; (ii) they undergo maturation both in vivo and in vitro; (iii) epigenetic factors, such as interactions with other neurotransmitter systems may modulate the developmental pattern of these two peptides.

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Large slope failures in fractured rocks are often controlled by the combination of pre-existing tectonic fracturing and brittle failure propagation in the intact rock mass during the pre-failure phase. This study focuses on the influence of fold-related fractures and of post-folding fractures on slope instabilities with emphasis on Turtle Mountain, located in SW Alberta (Canada). The structural features of Turtle Mountain, especially to the south of the 1903 Frank Slide, were investigated using a high-resolution digital elevation model combined with a detailed field survey. These investigations allowed the identification of six main discontinuity sets influencing the slope instability and surface morphology. According to the different deformation phases affecting the area, the potential origin of the detected fractures was assessed. Three discontinuity sets are correlated with the folding phase and the others with post-folding movements. In order to characterize the rock mass quality in the different portions of the Turtle Mountain anticline, the geological strength index (GSI) has been estimated. The GSI results show a decrease in rock mass quality approaching the fold hinge area due to higher fracture persistence and higher weathering. These observations allow us to propose a model for the potential failure mechanisms related to fold structures.