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11.
The Florida Department of Transportation (FDOT) is in the process of implementing Pontis, a Bridge Management System, to provide decision support to engineers in the headquarters and district offices as they make routine policy, programming, and budgeting decisions regarding the preservation and improvement of the state’s bridges. As part of this effort, an ongoing research program is underway to adapt the system to FDOT needs as well as to advance the state of the art in several areas important to the Department. Most of the research results are organized around a new project-level decision support framework that complements and builds on Pontis’ existing network-level analysis. Specific new models include accident risk and user cost due to roadway width and alignment deficiencies; user cost of load capacity and vertical clearance restrictions, and moveable bridge openings; project-level prediction models for bridge element condition and costs; and prediction of economics of scale and scoping possibilities. The new models are built into a highly graphical spreadsheet model for decision support use. 相似文献
12.
Undergraduate software engineering education is now well established in many countries, and many of these degree programs have received formal accreditation by the relevant country's professional body for computing. SE 2004 represents an enormous effort by numerous individuals across the discipline. Its quality has been clearly recognized by the sponsoring organizations. The developmental team confidently looks forward to the volume's use and to your participation in future evaluations and in the next phase of development. The volume provides usable results for those in emerging economies who wish to enter the software engineering community, and we know that individual project members and the participating national bodies are ready to assist. 相似文献
13.
Mike Thompson 《今日电子》2008,(4):43-44
构建和维护合适的功率环境对系统的正确运行非常关键。对功率的控制和管理越来越受到重视,无论是简单的手持式便携设备,还是多服务器机架系统,都希望能够节省能耗、降低成本。 相似文献
14.
There are four ecologically important river catchments that contain candidate Special Areas of Conservation (cSACs) under the Habitats Directive in the Lake District National Park located in the North of England. These are the rivers Ehen, Kent, Derwent and Eden. For each cSAC, there are defined ecological criteria that include water quality targets to protect the designated species. Stretches of the riverine cSACs in each catchment are failing to meet these and other water quality targets. The Environment Agency commissioned a study of each catchment to provide the underpinning scientific knowledge to allow it to deliver its statutory obligations under the Habitats Directive. SIMCAT river water quality models were produced and used to predict the water quality impacts resulting from a number of water quality planning scenarios aimed at achieving full compliance with the Habitats Directive and other national and EEC water quality targets. The results indicated that further controls on effluent discharges will allow the majority of targets to be met but other sources of pollution will also need to be controlled. The outcome of the study also recognised that water quality improvements alone will not necessarily produce the required improvement to the ecological interest features in each cSAC. 相似文献
15.
Ronald R. Delyser Sheila S. Thompson Jerry Edelstein Corinne Lengsfeld Albert J. Rosa Paul J. Rullkoetter Robert Whitman Margaret Whitt 《工程教育杂志》2003,92(3):269-273
A team of faculty members at the University of Denver changed the learning environment in key courses in the Department of Engineering from predominately teacher centered to student centered. Through this funded project new grading methods were implemented, classrooms were renovated and wired with studio layouts to facilitate learning, the Engineering Circuits Laboratory was rewired and instrumented for automated data acquisition and reporting, and two new pedagogical approaches were developed. At the onset of the project, six goals were established related to student learning. The introduction of industry standard hardware and software provided students with unprecedented hands‐on experience and project related activities stimulated faculty innovations in other current and future courses. Assessment results indicate that the new grading system improved the clarity of expectations for students before assignments were given resulting in increased reported motivation for learning in many courses. Even though course GPAs did not always reflect higher achievement on graded work, faculty members firmly believe that deeper understanding was achieved because more complex material was assimilated. 相似文献
16.
MD Goldberg JR Canvin P Freestone C Andersen D Laoudj PH Williams IB Holland V Norris 《Canadian Metallurgical Quarterly》1997,79(6):315-322
In the bacterium Escherichia coli, H-NS-(H1, H1a) is a heat-stable protein with a molecular mass of 15.5 kDa involved in nucleoid organisation and gene regulation linked to certain signal transduction pathways. We have shown that, following addition of preparations of everted inner membrane vesicles, heat-stable cleavage products of approximately 10 kDa of H-NS are formed in vitro from newly synthesised, radio-labelled H-NS and from purified H-NS. The 15.5 kDa protein and its cleavage products were also recovered from a minicell system. These results raised the possibility that cleavage of H-NS is physiologically significant. However, the cleavage of H-NS observed appears to occur during cell breakage and to depend on the method of protein extraction and the presence of the outer membrane protease, OmpT. Nevertheless, the results indicate that H-NS may contain at least two separate domains with cleavage occurring between these domains at a preferred OmpT site. Failure to take account of H-NS cleavage in sample preparation and analysis can lead to serious underestimation of H-NS levels. 相似文献
17.
18.
INTRODUCTION: Steady-state Na/K pump current (Ip) in adult guinea pig ventricular myocytes was studied to determine the effect on the Na/K pump of transmembrane Na leak, membrane potential, and pipette Na concentration. METHODS AND RESULTS: Using conventional whole cell, patch clamp techniques, Ip was identified as either Ko-sensitive or ouabain-sensitive current when most other membrane currents were inhibited. Control experiments showed that there were no Ko-sensitive currents other than Ip under the conditions of our experiments. Ip was found to be similar to that reported by others being voltage dependent between -130 and 0 mV and having a half maximal activation by Nai of 28 mM. Ouabain sensitivity was also measured, and it was found that there were two binding sites with the high affinity site comprising 5% to 10% of the total and having an apparent affinity 1000-fold higher than the low affinity site. Apparent affinity of both sites was shifted about 10-fold (higher affinity) by increasing Nai from 10 to 85 mM. When internally perfused with 0 Na solution, Na leak through the membrane was found to be linearly related to Na/K pump activity. In contrast to prior suggestions, Ip was not correlated with series resistance when there was a large transmembrane Na gradient. CONCLUSION: These data suggest that, under conditions of high transmembrane Na gradient, Na leak through the membrane plays a significant role in determining Na/K pump activity. 相似文献
19.
Cervical involvement is one of the major prognostic factors in carcinoma of the endometrium confined to the uterus. The purpose of this study was to determine whether intrauterine ultrasound with a high-frequency miniature probe can depict the degree of cervical involvement of the disease. Thirty-two women with endometrial carcinoma underwent preoperative transvaginal and intrauterine sonography. By both scans, the degree of cervical involvement was prospectively evaluated. Sonograms were compared with the findings from histologic examination. Intrauterine sonography was completed in 30 of the 32 patients. In these 30 patients, the degree of cervical involvement (none, endocervical gland, or cervical stroma) based on transvaginal scan was correct in 23 cases (77%), and that based on intrauterine scan was correct in 26 cases (87%). Three tumors with endocervical glandular involvement were correctly diagnosed by intrauterine sonography, whereas they were incorrectly diagnosed by transvaginal scan. The specificity and positive predictive value of intrauterine sonography for the assessment of the presence of cervical stromal invasion are 100% (26/26 and 3/3, respectively). Although this study is preliminary, our experience with intrauterine sonography shows that it has potential for assessing cervical stromal invasion in endometrial carcinoma. 相似文献
20.
JR Stout TJ Housh GO Johnson TK Evetovich DB Smith 《Canadian Metallurgical Quarterly》1997,76(4):363-367
Brucella abortus strain RB51 was recently approved as an official brucellosis calfhood vaccine for cattle by the Animal and Plant Health Inspection Service branch of the United States Department of Agriculture. Currently available serologic surveillance tests for B. abortus do not detect seroconversion following SRB51 vaccination. The purpose of this study was to evaluate a dot-blot assay using gamma-irradiated strain RB51 bacteria for its specificity and sensitivity to detect antibody responses of cattle vaccinated with strain RB51. Dot-blot titers of sera at a recommended dosage (10(10) colony-forming units) were similar to those of sera from cattle vaccinated with similar numbers of B. abortus strain 19 and greater (P < 0.05) than titers of nonvaccinated cattle. In the first 12 weeks after vaccination with 10(10) colony-forming units of strain RB51, the RB51 dot-blot assay had 100% specificity for titers of 80 or less and a 53% sensitivity for titers of 160 or greater. Sensitivity of the RB51 dot-blot assay peaked at 4 weeks after vaccination with 10(10) colony-forming units of strain RB51. Dot-blot responses of sera from cattle vaccinated with a reduced dosage of strain RB51 (10(9) colony-forming units) did not differ (P > 0.05) from titers of sera from nonvaccinated cattle. Following intraconjunctival challenge with B. abortus strain 2308, titers on the RB51 dot-blot assay did not differ (P > 0.05) between nonvaccinated cattle and cattle vaccinated at calfhood with strain 19 or strain RB51. 相似文献