WorldWideScience

Sample records for bleeding pavements

  1. Maintenance Solutions for Bleeding and Flushed Pavements Surfaced with a Seal Coat or Surface Treatment

    Science.gov (United States)

    2007-02-01

    This report summarizes the findings of research directed at identifying maintenance solutions for bleeding and : flushed asphalt pavements surfaced with seal coats or surface treatments. Although the basic mechanism associated with : both bleeding an...

  2. Bleeding

    Science.gov (United States)

    ... with problems in the joints, or gastrointestinal or urogenital tracts. Symptoms You may have symptoms such as: Blood ... may be internal bleeding or shock. Signs of infection develop, including increased pain, redness, swelling, yellow or ...

  3. Vaginal Bleeding

    Science.gov (United States)

    ... Gynecology. ACOG Practice Bulletin No. 128. Diagnosis of abnormal uterine bleeding in reproductive-aged women. Obstetrics and Gynecology. 2012;120:197. Kaunitz AM. Approach to abnormal uterine bleeding in nonpregnant reproductive-age women. http://www.uptodate. ...

  4. Perimenopausal Bleeding and Bleeding After Menopause

    Science.gov (United States)

    ... Patients About ACOG Perimenopausal Bleeding and Bleeding After Menopause Home For Patients Search FAQs Perimenopausal Bleeding and ... 2011 PDF Format Perimenopausal Bleeding and Bleeding After Menopause Gynecologic Problems What are menopause and perimenopause? What ...

  5. Rigid pavements distresses - pavement condition index evaluation

    OpenAIRE

    Pereira, Tiago David da Costa Prudente

    2014-01-01

    Pavements require maintenance in order to provide good service levels during their life period. Because of the significant costs of this operation and the importance of a proper planning, a pavement evaluation methodology, named Pavement Condition Index (PCI), was created by the U.S. Army Corps of Engineers. This methodology allows for the evaluation of the pavement condition along the life period, generally yearly, with minimum costs and, in this way, it is possible to plan the maintenance a...

  6. [Gastrointestinal bleeding].

    Science.gov (United States)

    Lanas, Ángel

    2015-09-01

    In the Digestive Disease Week in 2015 there have been some new contributions in the field of gastrointestinal bleeding that deserve to be highlighted. Treatment of celecoxib with a proton pump inhibitor is safer than treatment with nonselective NSAID and a proton pump inhibitor in high risk gastrointestinal and cardiovascular patients who mostly also take acetylsalicylic acid. Several studies confirm the need to restart the antiplatelet or anticoagulant therapy at an early stage after a gastrointestinal hemorrhage. The need for urgent endoscopy before 6-12 h after the onset of upper gastrointestinal bleeding episode may be beneficial in patients with hemodynamic instability and high risk for comorbidity. It is confirmed that in Western but not in Japanese populations, gastrointestinal bleeding episodes admitted to hospital during weekend days are associated with a worse prognosis associated with delays in the clinical management of the events. The strategy of a restrictive policy on blood transfusions during an upper GI bleeding event has been challenged. Several studies have shown the benefit of identifying the bleeding vessel in non varicose underlying gastric lesions by Doppler ultrasound which allows direct endoscopic therapy in the patient with upper GI bleeding. Finally, it has been reported that lower gastrointestinal bleeding diverticula band ligation or hemoclipping are both safe and have the same long-term outcomes. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

  7. Rectal Bleeding

    Science.gov (United States)

    ... rectal bleeding and any signs of shock: Rapid, shallow breathing Dizziness or lightheadedness after standing up Blurred ... shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research. © 1998-2018 Mayo ...

  8. Permeable pavement study (Edison)

    Data.gov (United States)

    U.S. Environmental Protection Agency — While permeable pavement is increasingly being used to control stormwater runoff, field-based, side-by-side investigations on the effects different pavement types...

  9. Saw & seal, airport pavement.

    Science.gov (United States)

    2009-05-01

    Due to extreme cold temperatures, hot bituminous pavements on Maines airports are subject to transverse : or thermal cracking. This can lead to poorly performing pavement structure causing heaving and : settlement problems. Studies have shown that...

  10. Pavement Subgrade Performance Study

    DEFF Research Database (Denmark)

    Zhang, Wei; Ullidtz, Per; Macdonald, Robin

    1998-01-01

    The report describes the second test in the Danish Road Testing Machine (RTM) under the International Pavement Subgrade Performance Study. Pavement response was measured in different layers, and compared to different theroretical values. Performance in terms of plastic strains, rutting...

  11. Quieter pavements guidance document

    Science.gov (United States)

    2013-02-01

    This report provides guidance and better practice recommendations to the National Park : Service for selecting pavement surfaces to minimize tire-pavement noise. The report : contains an overview of common technologies and methods for quieter pavemen...

  12. Concrete pavement joint deterioration.

    Science.gov (United States)

    2015-12-01

    Concrete pavements are an important part of our national infrastructure. In recent years the relatively small number of reported joints deteriorating prematurely in concrete pavements around Indiana has increased. Changes over the past 45 years in IN...

  13. Bleeding Disorders

    Science.gov (United States)

    ... study of intranasal desmopressin and oral tranexamic acid . British Journal of Haematology; 145(2): 212-220. Bleeding ... Ayisyen Français Polski Português Italiano Deutsch 日本語 فارسی English A federal government website managed by the Office ...

  14. Abnormal uterine bleeding

    Science.gov (United States)

    Anovulatory bleeding; Abnormal uterine bleeding - hormonal; Polymenorrhea - dysfunctional uterine bleeding ... ACOG committee opinion no. 557: Management of acute abnormal uterine bleeding in nonpregnant reproductive-aged women. Reaffirmed 2015. ACOG. ...

  15. Pavement Testing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Comprehensive Environmental and Structural AnalysesThe ERDC Pavement Testing Facility, located on the ERDC Vicksburg campus, was originally constructed to provide an...

  16. Pervious Pavement System Evaluation

    Science.gov (United States)

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, grade...

  17. Desert Pavement Studies

    National Research Council Canada - National Science Library

    Haff, Peter

    2003-01-01

    Combining plan view information from aerial photography showing details of stream channels on desert pavement surfaces with process-based erosion models, a high-resolution, synthetic topography DEM...

  18. Permeable pavement study (Edison)

    Science.gov (United States)

    While permeable pavement is increasingly being used to control stormwater runoff, field-based, side-by-side investigations on the effects different pavement types have on nutrient concentrations present in stormwater runoff are limited. In 2009, the U.S. EPA constructed a 0.4-ha parking lot in Edison, New Jersey, that incorporated permeable interlocking concrete pavement (PICP), pervious concrete (PC), and porous asphalt (PA). Each permeable pavement type has four, 54.9-m2, lined sections that direct all infiltrate into 5.7-m3 tanks enabling complete volume collection and sampling. This paper highlights the results from a 12-month period when samples were collected from 13 rainfall/runoff events and analyzed for nitrogen species, orthophosphate, and organic carbon. Differences in infiltrate concentrations among the three permeable pavement types were assessed and compared with concentrations in rainwater samples and impervious asphalt runoff samples, which were collected as controls. Contrary to expectations based on the literature, the PA infiltrate had significantly larger total nitrogen (TN) concentrations than runoff and infiltrate from the other two permeable pavement types, indicating that nitrogen leached from materials in the PA strata. There was no significant difference in TN concentration between runoff and infiltrate from either PICP or PC, but TN in runoff was significantly larger than in the rainwater, suggesting meaningful inter-event dry de

  19. Consideration of pavement roughness effects on vehicle-pavement interaction

    CSIR Research Space (South Africa)

    Steyn, WJvdM

    2001-07-01

    Full Text Available The aim of this paper is to present some of the results of the vehicle-pavement interaction project, mainly in terms of the expected effects of pavement roughness on the moving dynamic effects in pavement analysis and design. Background is provided...

  20. Flexible pavement rehabilitation using pulverization.

    Science.gov (United States)

    2008-06-01

    Pulverization is a roadway rehabilitation strategy that involves in-place recycling of the entire existing flexible pavement layer and some of the existing granular base layer (Figure 1). Pavement pulverization provides an alternative to conventional...

  1. Training development for pavement preservation.

    Science.gov (United States)

    2013-05-01

    This research project strives to help the Iowa Department of Transportation (DOT) fully achieve the full benefits of pavement : preservation through training on proper selection, design, and application of pavement preservation treatments. In some ca...

  2. Development of Enhanced Pavement Deterioration Curves

    OpenAIRE

    Ercisli, Safak

    2015-01-01

    Modeling pavement deterioration and predicting the pavement performance is crucial for optimum pavement network management. Currently only a few models exist that incorporate the structural capacity of the pavements into deterioration modeling. This thesis develops pavement deterioration models that take into account, along with the age of the pavement, the pavement structural condition expressed in terms of the Modified Structural Index (MSI). The research found MSI to be a significant input...

  3. Optimization and standardization of pavement management processes.

    Science.gov (United States)

    2004-08-01

    This report addresses issues related to optimization and standardization of current pavement management processes in Kentucky. Historical pavement management records were analyzed, which indicates that standardization is necessary in future pavement ...

  4. Permeable Pavements at Purdue

    OpenAIRE

    Knapp, Jim

    2013-01-01

    Two case studies will be presented describing sustainable drainage alternatives. The processes used for the 2nd Street project in Seymour will provide a comparison of the design processes for conventional and green infrastructure solutions. Purdue University will discuss a number of permeable pavement installations on campus and provide a map for viewing. Asphalt, concrete, and permeable paver options will be discussed.

  5. Advances in gastrointestinal bleeding.

    Science.gov (United States)

    Lanas, Ángel

    2016-09-01

    The main innovations of the latest meeting of the Gastroenterological Association (2016) concerning upper gastrointestinal bleeding from the clinician's perspective can be summarised as follows: a) The Glasgow-Blatchford scale has the best accuracy in predicting the need for surgical intervention and hospital mortality; b) Prognostic scales for non-variceal upper gastrointestinal bleeding are also useful for lower gastrointestinal bleeding; c) Preliminary data suggest that treatment with hemospray does not seem to be superior to current standard treatment in controlling active peptic ulcer bleeding; d) Either famotidine or a proton pump inhibitor may be effective in preventing haemorrhagic recurrence in patients taking aspirin, but this finding needs to be confirmed in further studies; e) There was confirmation of the need to re-introduce antiplatelet therapy as early as possible in patients with antiplatelet-associated gastrointestinal bleeding in order to prevent cardiovascular mortality; f) Routine clinical practice suggests that gastrointestinal or cardiovascular complications with celecoxib or traditional NSAIDs are very low; g) Dabigatran is associated with an increased incidence of gastrointestinal bleeding compared with apixaban or warfarin. At least half of the episodes are located in the lower gastrointestinal tract; h) Implant devices for external ventricular circulatory support are associated with early gastrointestinal bleeding in up to one third of patients; the bleeding is often secondary to arteriovenous malformations. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  6. Bleeding esophageal varices

    Science.gov (United States)

    ... amount of bleeding, the only symptom may be dark or black streaks in the stools. If larger amounts of bleeding occur, symptoms ... exam which may show: Bloody or black stool (in a rectal exam) Low ... the use of a camera on a flexible tube to examine the esophagus ...

  7. Assessment of Postmenopausal Bleeding

    Directory of Open Access Journals (Sweden)

    Chin-Yuan Hsu

    2008-06-01

    Full Text Available Postmenopausal bleeding is bleeding that occurs 12 or more months after the last menstrual period and accounts for 5% of all gynecologic office visits. While it is not always a symptom of cancer, the exclusion of endometrial hyperplasia and carcinoma is the key issue in the evaluation of patients with postmenopausal bleeding. The primary evaluation of postmenopausal women who present with abnormal uterine bleeding includes a medical history and a pelvic examination. Investigative studies, such as a uterine biopsy, ultrasound, hysteroscopy or dilation and curettage, may be required. Treatment will depend on the cause determined. The most important point is that irregular perimenopausal or postmenopausal bleeding should not be ignored or assumed to be a normal phenomenon.

  8. Incorporating Traffic Speed Deflection Data in Pavement Management Decision Making for Flexible Pavements

    OpenAIRE

    Thyagarajan, Senthilmurugan; Sivaneswaran, Nadarajah; Petros, Katherine

    2015-01-01

    Systematic pavement condition evaluation and development of an optimized set of pavement treatment strategies are two key tasks in the pavement management process that assists in making informed decisions on future construction actions. Current State Highway Agency's pavement management systems are primarily based on surface condition data, and surface cracking is mainly used as an indicator of the pavement structural condition. However, with effective pavement preservation activities that in...

  9. Abnormal Uterine Bleeding

    Science.gov (United States)

    ... uterine cancer isn’t the cause. Women after menopause Hormone replacement therapy is a common cause of uterine bleeding after menopause. Other causes include endometrial and uterine cancer. These ...

  10. Tire-Pavement Friction Characteristics with Elastic Properties of Asphalt Pavements

    Directory of Open Access Journals (Sweden)

    Miao Yu

    2017-11-01

    Full Text Available The skid-resisting performance of pavement is a critical factor in traffic safety. Recent studies primarily analyze this behavior by examining the macro or micro texture of the pavement. It is inevitable that skid-resistance declines with time because the texture of pavement deteriorates throughout its service life. The primary objective of this paper is to evaluate the use of different asphalt pavements, varying in resilience, to optimize braking performance on pavement. Based on the systematic dynamics of tire-pavement contact, and analysis of the tire-road coupled friction mechanism and the effect of enlarging the tire-pavement contact area, road skid resistance was investigated by altering the elastic modulus of asphalt pavement. First, this research constructed the kinetic contact model to simulate tire-pavement friction. Next, the following aspects of contact behaviors were studied when braking: tread deformation in the tangential pavement interface, actual tire-pavement contact in the course, and the frictional braking force transmitted from the pavement to the tires. It was observed that with improvements in pavement elasticity, the actual tire-pavement contact area increased, which gives us the ability to effectively strengthen the frictional adhesion of the tire to the pavement. It should not be overlooked that the improvement in skid resistance was caused by an increase in pavement elasticity. This research approach provides a theoretical basis and design reference for the anti-skid research of asphalt pavements.

  11. Pervious Pavement System Evaluation- Abstract

    Science.gov (United States)

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, gra...

  12. Premature asphalt concrete pavement cracking.

    Science.gov (United States)

    2015-06-01

    Recently, the Oregon Department of Transportation (ODOT) has identified hot mix asphalt concrete : (HMAC) pavements that have displayed top-down cracking within three years of construction. The objective of : the study was to evaluate the top-down cr...

  13. Pavement management using hyperspectral imagery

    Science.gov (United States)

    Ayalew, Balehager; Gomez, Richard B.; Roper, William E.; Carrasco, Oscar

    2003-08-01

    Public Works facilities require up-to-date information on the health status of the road network they maintain. However, roadway maintenance and rehabilitation involves the greatest portion of a municipality's annual operating budget. Government officials use various technologies such as a pavement management system to assist in making better decisions about their roadways systems, pavement condition, history, and projects. Traditionally, manual surveying has served as the method of obtaining this information. To better assist in decision-making, a regionally specific spectral library for urban areas is being developed and used in conjunction with hyperspecrtal imaging, to map urban materials and pavement conditions. A Geographical Information and Positioning System (GIS/GPS) will also be implemented to overlay relative locations. This paper will examine the benefits of using hyperspectral imaging over traditional methods of roadway maintenance and rehabilitation for pavement management applications. In doing so, we will identify spatial and spectral requirements for successful large-scale road feature extraction.

  14. Environmentally Friendly Pavements: final report

    OpenAIRE

    Aksnes, Jostein

    2009-01-01

    This final report presents the main results, advice and recommendations from the research and development program Environmentally Friendly Pavements run by the Norwegian Public Roads Administration (NPRA) in the period 2004-2009. The main focus of the project has been to optimise the environmental properties of road surfaces with respect to low road tyre noise and road dust emissions. The project has shown that: The tested environmentally friendly pavements give an initial noise r...

  15. Fracture mechanics in pavement design

    CSIR Research Space (South Africa)

    Denneman, E

    2009-07-01

    Full Text Available MODELLING FRACTURE IN PAVEMENT MATERIALS The cohesive crack approach can be incorporated in finite element method (FEM) to simulate fracture in pavement materials. In this paper an embedded discontinuity method (EDM) based on the work by Sancho et al... through elements, in other words, independent of nodal positions and element boundaries. The EDM was used for the numerical simulation of two examples of fracture tests on road materials from the literature. The model is applied to reproduce...

  16. Intelligent system for pavement management

    Science.gov (United States)

    Ferreira Brega, Jose R.; Alba Soria, Manoel H.; Marar, Joao F.; Sementille, Antonio C.

    1998-03-01

    This paper describes a method for the evaluation of pavement condition through artificial neural networks using the MLP backpropagation technique. Two of the most used procedures for detecting the pavement conditions were applied: the 'overall severity index' and the 'irregularity index.' Tests with the model demonstrated that the simulation with the neural network gives better results than the procedures recommended by the highway officials. This network may also be applied for the construction of a graphic computer environment.

  17. HYSTEROSCOPY IN POSTMENOPAUSAL BLEEDING.

    Science.gov (United States)

    Vardhan, S; Mohan, S; Ranjan, P

    2001-04-01

    The purpose of the present study was to evaluate the utility of hysteroscopy as a diagnostic tool in cases of postmenopausal bleeding. The study includes 42 cases presenting with postmenopausal bleeding on which hysterscopy was performed using rigid hysteroscope (CIRCON) with glycine 1.5% as the distension medium. In 17 of the 42 cases positive hysteroscopic findings were noted which included 2 cases of endometrial carcinoma, 2 cases of postmenopausal endometritis, 4 cases of endometrial polyp, 5 cases of endometrial hyperplasia, 1 case of submucous myoma and 3 cases of endocervical polyp whereas normal postmenopausal endometrium was noticed in rest of the 25 cases. Endometrial biopsy was done in all these cases so that the hysteroscopic findings could be corroborated with tissue diagnosis. Hysteroscopy along with directed endometrial biopsy proved to be a useful diagnostic aid in cases of postmenopausal bleeding.

  18. Calibration of PMIS pavement performance prediction models.

    Science.gov (United States)

    2012-02-01

    Improve the accuracy of TxDOTs existing pavement performance prediction models through calibrating these models using actual field data obtained from the Pavement Management Information System (PMIS). : Ensure logical performance superiority patte...

  19. Appraisal of the Causes of Pavement

    African Journals Online (AJOL)

    used environmental observations in addition to geotechnical test to study ... 1Department of Applied Geophysics, Federal University of Technology, Akure, Nigeria ... have contributed to the pavement failure. Keywords: Remote Sensing, Geotechnical Investigation, Road Pavement Failure, Basement Complex. Environment.

  20. Pervious Pavement System Evaluation-Poster

    Science.gov (United States)

    Pervious pavement is a low impact development stormwater control. The Environmental Protection Agency's Urban Watershed Management Branch is evaluating interlocking concrete pavingstone pervious pavement systems. The pavingstones themselves are impermeable, but the spaces between...

  1. Equivalent damage of loads on pavements

    CSIR Research Space (South Africa)

    Prozzi, JA

    2009-05-26

    Full Text Available This report describes a new methodology for the determination of Equivalent Damage Factors (EDFs) of vehicles with multiple axle and wheel configurations on pavements. The basic premise of this new procedure is that "equivalent pavement response...

  2. Dynamic contracting mechanism for pavement maintenance management

    NARCIS (Netherlands)

    Demirel, H.C.; De Ridder, H.A.J.

    2013-01-01

    Technological advances, financial possibilities and changes of demands have increasingly affected the pavement maintenance environment for outsourcing in recent years. This induces complexity in the contracting methods of pavement maintenance activities. Despite the fact that current contracting

  3. Minimization of reflection cracks in flexible pavements.

    Science.gov (United States)

    1977-01-01

    This report describes the performance of fabrics used under overlays in an effort to minimize longitudinal and alligator cracking in flexible pavements. It is concluded, although the sample size is small, that the treatments will extend the pavement ...

  4. Evaluation of pavement surface friction treatments.

    Science.gov (United States)

    2011-12-01

    The implementation of a pavement preservation program involves a learning curve with not only a determination to succeed, but : also the courage to fail. Also, successful implementation of pavement preservation program requires knowledge of the perfo...

  5. Serviceable pavement marking retroreflectivity levels : technical report.

    Science.gov (United States)

    2009-03-01

    This research addressed an array of issues related to measuring pavement markings retroreflectivity, factors : related to pavement marking performance, subjective evaluation process, best practices for using mobile : retroreflectometers, sampling pav...

  6. An approach to pavement management in Virginia.

    Science.gov (United States)

    1981-01-01

    The report summarizes the objectives and benefits of formal pavement management systems and outlines an approach believed by the author to be practical for Virginia. The management of Virginia interstate pavements and a proposed random-sampling plan ...

  7. Sustainable concrete pavements : a manual of practice.

    Science.gov (United States)

    2011-08-01

    Developed as a more detailed follow-up to a 2009 briefing document, Building Sustainable Pavement with Concrete, this guide provides a clear, concise, and cohesive discussion of pavement sustainability concepts and of recommended practices for maximi...

  8. Pavement performance evaluation, phase II : data collection.

    Science.gov (United States)

    2008-12-01

    Phase I and II of this study tested approximately 1500 rehabilitated pavements (asphalt and PCC) : throughout the State. These pavements ranged from 5 to 15 years old and were intended to develop a : snapshot of how various rehabilitations were perfo...

  9. Quantifying Evaporation in a Permeable Pavement System

    Science.gov (United States)

    Studies quantifying evaporation from permeable pavement systems are limited to a few laboratory studies and one field application. This research quantifies evaporation for a larger-scale field application by measuring the water balance from lined permeable pavement sections. Th...

  10. High Performance Concrete Pavement in Indiana

    OpenAIRE

    Nantung, Tommy E

    2011-01-01

    Until the early 1990s, curling and warping of Portland cement concrete pavement did not concern pavement engineers in many transportation agencies. Since beginning construction of the interstate system in the United States in the late 1950s through the late 1980s, the performance of Portland cement concrete pavement has been associated with properties of concrete as a pavement material. In those years developed standards and design guidelines emphasized better concrete materials and construct...

  11. Heavy Menstrual Bleeding

    Science.gov (United States)

    ... option. It also is used to treat endometrial cancer. After the uterus is removed, a woman can no longer get ... to stop or reduce menstrual bleeding. Endometrial Cancer: Cancer of the lining of the uterus. Endometrial Biopsy: A procedure in which a small ...

  12. Bleeding Disorders Treatment Options

    Science.gov (United States)

    ... rare bleeding disorders are usually made from human plasma and are treated to eliminate viruses like HIV and hepatitis B and C. ... concentrate (PCC) This concentrate is made from human plasma and ... (VKCFD). It is treated to eliminate viruses like HIV and hepatitis B and C. ...

  13. Impact of pavement conditions on crash severity.

    Science.gov (United States)

    Li, Yingfeng; Liu, Chunxiao; Ding, Liang

    2013-10-01

    Pavement condition has been known as a key factor related to ride quality, but it is less clear how exactly pavement conditions are related to traffic crashes. The researchers used Geographic Information System (GIS) to link Texas Department of Transportation (TxDOT) Crash Record Information System (CRIS) data and Pavement Management Information System (PMIS) data, which provided an opportunity to examine the impact of pavement conditions on traffic crashes in depth. The study analyzed the correlation between several key pavement condition ratings or scores and crash severity based on a large number of crashes in Texas between 2008 and 2009. The results in general suggested that poor pavement condition scores and ratings were associated with proportionally more severe crashes, but very poor pavement conditions were actually associated with less severe crashes. Very good pavement conditions might induce speeding behaviors and therefore could have caused more severe crashes, especially on non-freeway arterials and during favorable driving conditions. In addition, the results showed that the effects of pavement conditions on crash severity were more evident for passenger vehicles than for commercial vehicles. These results provide insights on how pavement conditions may have contributed to crashes, which may be valuable for safety improvement during pavement design and maintenance. Readers should notice that, although the study found statistically significant effects of pavement variables on crash severity, the effects were rather minor in reality as suggested by frequency analyses. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Pavement noise measurements in Poland

    Science.gov (United States)

    Zofka, Ewa; Zofka, Adam; Mechowski, Tomasz

    2017-09-01

    The objective of this study is to investigate the feasibility of the On-Board Sound Intensity (OBSI) system to measure tire-pavement noise in Poland. In general, sources of noise emitted by the modern vehicles are the propulsion noise, aerodynamic resistance and noise generated at the tire-pavement interface. In order to capture tire-pavement noise, the OBSI system uses a noise intensity probe installed in the close proximity of that interface. In this study, OBSI measurements were performed at different types of pavement surfaces such as stone mastic asphalt (SMA), regular asphalt concrete (HMA) as well as Portland cement concrete (PCC). The influence of several necessary OBSI measurement conditions were recognized as: testing speed, air temperature, tire pressure and tire type. The results of this study demonstrate that the OBSI system is a viable and robust tool that can be used for the quality evaluation of newly built asphalt pavements in Poland. It can be also applied to generate reliable input parameters for the noise propagation models that are used to assess the environmental impact of new and existing highway corridors.

  15. Vaginal or uterine bleeding - overview

    Science.gov (United States)

    ... Metrorrhagia and other menstrual conditions; Abnormal menstrual periods; Abnormal vaginal bleeding ... of regular ovulation (anovulation). Doctors call the problem abnormal uterine bleeding (AUB) . AUB is more common in teenagers and ...

  16. Geo synthetic-reinforced Pavement systems

    International Nuclear Information System (INIS)

    Zornberg, J. G.

    2014-01-01

    Geo synthetics have been used as reinforcement inclusions to improve pavement performance. while there are clear field evidence of the benefit of using geo synthetic reinforcements, the specific conditions or mechanisms that govern the reinforcement of pavements are, at best, unclear and have remained largely unmeasured. Significant research has been recently conducted with the objectives of: (i) determining the relevant properties of geo synthetics that contribute to the enhanced performance of pavement systems, (ii) developing appropriate analytical, laboratory and field methods capable of quantifying the pavement performance, and (iii) enabling the prediction of pavement performance as a function of the properties of the various types of geo synthetics. (Author)

  17. Pavement thickness evaluation using ground penetrating radar

    Science.gov (United States)

    Harris, Dwayne Arthur

    Accurate knowledge of pavement thickness is important information to have both at a network and project level. This information aids in pavement management and design. Much of the time this information is missing, out of date, or unknown for highway sections. Current technologies for determining pavement thickness are core drilling, falling weight deflectometer (FWD), and ground penetrating radar (GPR). Core drilling provides very accurate pin point pavement thickness information; however, it is also time consuming, labor intensive, intrusive to traffic, destructive, and limited in coverage. FWD provides nondestructive estimates of both a surface thickness and total pavement structure thickness, including pavement, base and sub-base. On the other hand, FWD is intrusive to traffic and affected by the limitations and assumptions the method used to estimate thickness. GPR provides pavement surface course thickness estimates with excellent data coverage at highway speed. Yet, disadvantages include the pavement thickness estimation being affected by the electrical properties of the pavement, limitations of the system utilized, and heavy post processing of the data. Nevertheless, GPR has been successfully utilized by a number of departments of transportation (DOTs) for pavement thickness evaluation. This research presents the GPR thickness evaluation methods, develops GPRPAVZ the software used to implement the methodologies, and addresses the quality of GPR pavement thickness evaluation.

  18. Pinworms and postmenopausal bleeding.

    OpenAIRE

    al-Rufaie, H K; Rix, G H; Pérez Clemente, M P; al-Shawaf, T

    1998-01-01

    The human pinworm Enterobius vermicularis is normally found within the human gastrointestinal tract. Pregnant females migrate out of their host's anus at night to lay their eggs perianally. As a consequence of this nocturnal migration some worms find their way into adjacent orifices, most commonly the female genitourinary tract, producing irritative symptoms such as vulvovaginitis. A case of pinworm infestation of the uterus presented as postmenopausal bleeding.

  19. Comparison of winter temperature profiles in asphalt and concrete pavements.

    Science.gov (United States)

    2014-06-01

    The objectives of this research were to 1) determine which pavement type, asphalt or concrete, has : higher surface temperatures in winter and 2) compare the subsurface temperatures under asphalt and : concrete pavements to determine the pavement typ...

  20. Minnesota Local Agency Pavement Marking : Mining Existing Data

    Science.gov (United States)

    2017-11-01

    Pavement marking is important for safety. Maximizing pavement marking performance in terms of increased retroreflectivity, within limited budget constraints, allows agencies to make better decisions toward providing more effective pavement marking pe...

  1. Texas flexible pavements overlays : review and analysis of existing databases.

    Science.gov (United States)

    2011-12-01

    Proper calibration of pavement design and rehabilitation performance models to : conditions in Texas is essential for cost-effective flexible pavement design. The degree of : excellence with which TxDOTs pavement design models is calibrated will d...

  2. Tuning in to pavement radio

    NARCIS (Netherlands)

    Ellis, S.D.K.

    1989-01-01

    This article describes a phenomenon known all over Africa, for which there is no really satisfactory term in English but which is summed up in the French term 'radio trottoir', literally 'pavement radio'. It may be defined as the popular and unofficial discussion of current affairs in Africa,

  3. The Concrete and Pavement Challenge

    Science.gov (United States)

    Roman, Harry T.

    2012-01-01

    The modern world is characterized by the extensive use of concrete and asphalt pavement. Periodically, these materials are replaced and the old materials disposed of. In this challenge, students will be asked to develop ways to reuse the old materials. It is important for students to understand how concrete and asphalt are made and applied, as…

  4. Mild bleeding disorders

    OpenAIRE

    PERROUD, V.

    2011-01-01

    Contrairement aux troubles hémorragiques sévères, les maladies hémorragiques modérées (Mild Bleeding Disorders = MBD) sont difficiles à diagnostiquer chez les enfants, car la limite entre le physiologique et le pathologique est mal définie et l'approche diagnostique est peu systématisée. Qu'entend-on par MBD ? On peut les définir comme des diathèses hémorragiques sans répercussion sévère sur la vie quotidienne et, en principe, sans risque vital : épistaxis, gingivorragies, rect...

  5. Feasibility of reclaimed asphalt pavement as aggregate in portland cement concrete pavements.

    Science.gov (United States)

    2013-11-01

    This research effort was focused on evaluating the feasibility of using minimally processed reclaimed : asphalt pavement (RAP) as aggregate replacement in concrete pavements. This research demonstrated : that concretes with up to 50 percent of the fi...

  6. Comparison of accelerated pavement test results with long term pavement behaviour and performance

    CSIR Research Space (South Africa)

    Jooste, FJ

    1997-08-01

    Full Text Available The aim of this study was to investigate the following:how accelerated pavement testing predictions compare with actual road behaviour and performance the relative influences of load and environmental factors on pavement deterioration and how well...

  7. An integrated pavement data management and feedback system (PAMS) : evaluation of pavement condition rating procedure.

    Science.gov (United States)

    1984-08-01

    This report describes an evaluation of a method for use in the Highway Needs Study pavement condition rating. The methods by which the Department generates and manages pavement condition data in the overall process of providing a network of highways ...

  8. Integration and Evaluation of Automated Pavement Distress Data in INDOT’s Pavement Management System

    Science.gov (United States)

    2017-05-01

    This study was in two parts. The first part established and demonstrated a framework for pavement data integration. This is critical for fulfilling QC/QA needs of INDOTs pavement management system, because the precision of the physical location re...

  9. Long-term pavement performance information management system : pavement performance database user reference guide

    Science.gov (United States)

    2003-11-01

    This document provides information to aid in understanding and using the Long-Term Pavement Performance (LTPP) program pavement performance database. This document provides an introduction to the structure of the LTPP program, the relational structur...

  10. Long-term pavement performance pavement loading user guide (LTPP PLUG).

    Science.gov (United States)

    2013-10-01

    "This guide addresses the selection and use of axle loading defaults for Mechanistic-Empirical Pavement Design : Guide (MEPDG) applications. The defaults were developed based on weigh-in-motion (WIM) data from the Long- : Term Pavement Performance (L...

  11. Application of the portable pavement seismic analyser (PSPA) for pavement analysis

    CSIR Research Space (South Africa)

    Steyn, WJVDM

    2007-07-01

    Full Text Available of pavement types, including Long-Term Pavement Performance (LTPP) sections and Heavy Vehicle Simulator (HVS) test sites. The data are analysed for repeatability, variability, isotropy, and ranges of seismic stiffness values. Information is provided...

  12. Advanced Pavement Design: Finite Element Modeling for Rigid Pavement Joints, Report II: Model Development

    National Research Council Canada - National Science Library

    Hammons, Michael

    1998-01-01

    .... The objective of this research was to obtain data on the response of the ng'id pavement slab-joint-foundation system by conducting laboratory-scale experiments on jointed rigid pavement models...

  13. MoDOT pavement preservation research program volume IV, pavement evaluation tools-data collection methods.

    Science.gov (United States)

    2015-10-01

    The overarching goal of the MoDOT Pavement Preservation Research Program, Task 3: Pavement Evaluation Tools Data : Collection Methods was to identify and evaluate methods to rapidly obtain network-level and project-level information relevant to :...

  14. Inverted base pavements: construction and performance

    KAUST Repository

    Papadopoulos, Efthymios

    2017-05-11

    Inverted base pavements involve a well-compacted granular aggregate base built between a thin asphalt concrete layer and a cement-treated base. Inverted base pavements can be constructed using conventional equipment and procedures but require proper quality control. This study reviews the extensive South African experience and case histories in the USA. Accumulating evidence suggests that inverted base pavements are a viable alternative and can outperform conventional pavements at a lower cost. Inverted base pavements rely on the complementary interaction between layers. The cement-treated base provides a stiff foundation for efficient compaction and constrains the deformation of the stress-sensitive granular aggregate base. The thin asphalt surface layer deforms as a membrane and develops low tensile stress. Additional large-scale field tests should be conducted to assess the performance of inverted base pavement designs in a wide range of conditions relevant to the USA.

  15. Cracking of open traffic rigid pavement

    OpenAIRE

    Niken Chatarina; Siswanto Yudi; Widodo; Tjahjono Elly

    2017-01-01

    The research is done by observing the growth of real structure cracking in Natar, Lampung, Indonesia compared to C. Niken’s et al research and literature study. The rigid pavement was done with open traffic system. There are two main crack types on Natar rigid pavement: cracks cross the road, and cracks spreads on rigid pavement surface. The observation of cracks was analyzed by analyzing material, casting, curing, loading and shrinkage mechanism. The relationship between these analysis and s...

  16. Bleeding in children with cancer

    African Journals Online (AJOL)

    Siluan early warning signs of childhood cancer, compiled by the South. African Children's Cancer Study Group (SACCSG). An increased risk of bleeding during the cancer treatment period is almost always present, due to the bone marrow suppressive effect of chemotherapy. Fortunately, death due to bleeding is rare these ...

  17. Treatment of acute variceal bleeding

    DEFF Research Database (Denmark)

    Bendtsen, Flemming; Krag, Aleksander Ahm; Møller, Søren

    2008-01-01

    to failure to control initial bleeding or early re-bleeding occurring in up to 30-40% of patients. Initial procedures are to secure and protect the airway, and administer volume replacement to stabilize the patient. Treatment with vasoactive drugs should be started as soon as possible, since a reduction...

  18. Evaluating life cycle costs of perpetual pavements in China using operational pavement management system

    Directory of Open Access Journals (Sweden)

    Saud A. Sultan

    2016-10-01

    Full Text Available Highway transportation is considered as vital factor in China’s economic growth; many high grade highways have been constructed in China during the last decades. The research and application of perpetual asphalt pavement (PP technology have been deployed in China since 2000. The semi-rigid pavement has been normally considered as typical pavement of high class highways in the design according to the Chinese experience. The objective of this research is to evaluate the performance of different Chinese perpetual pavements using operational pavement management system and to examine its suitability for use in the design and construction of more economical and durable pavements. It has been found that the use of thin asphalt layers over semi-rigid pavement foundation in PP structure will create more sustainable, economical, and durable PP structures in comparison with typical thick asphalt layers PP structures.

  19. Performance of upper gastrointestinal bleeding risk assessment scores in variceal bleeding

    DEFF Research Database (Denmark)

    Ngu, Jing H.; Laursen, Stig Borbjerg; Chin, YK

    2017-01-01

    Performance of upper gastrointestinal bleeding risk assessment scores in variceal bleeding: a prospective international multicenter study.......Performance of upper gastrointestinal bleeding risk assessment scores in variceal bleeding: a prospective international multicenter study....

  20. Appraisal of the Causes of Pavement

    African Journals Online (AJOL)

    INTRODUCTION. Pavement failures are very common features on. Nigeria in roads after few years of performance and often before attaining the design age. These roads are continuously reconstructed or rehabilitated without any effort made to identify factor(s) responsible for their perpetual failure. Pavement failures can ...

  1. Load Response Analysis of Asphalt Pavement

    Directory of Open Access Journals (Sweden)

    Xiao Zhijun

    2016-01-01

    Full Text Available Based on the filed data of Fuzhou test road, load response regulation of nonlinear pavement structure was analyzed in this paper; Mechanics software was adopted to analyze linear elastic and nonlinear of the pavement structure, analyzed results and road filed data were compared, and determine the correlation between them and the field data.

  2. Pervious Pavement System Evaluation-Paper

    Science.gov (United States)

    The use of a pervious pavement can be effective as a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete paver systems as a type of porous pavement. Although the pavers are impermeable, the spaces between the pave...

  3. Numerical Simulation of Tire-Pavement Interaction

    NARCIS (Netherlands)

    Srirangam, S.K.

    2015-01-01

    Good skid resistance of a pavement surface is essential for road safety. Loss of skid resistance can lead to property damage and loss of lives. Ever increasing need of driver safety poses challenges to the highway authorities to evaluate pavement conditions even more precisely under different

  4. Crackscope : automatic pavement cracking inspection system.

    Science.gov (United States)

    2008-08-01

    The CrackScope system is an automated pavement crack rating system consisting of a : digital line scan camera, laser-line illuminator, and proprietary crack detection and classification : software. CrackScope is able to perform real-time pavement ins...

  5. Modelling Flexible Pavement Response and Performance

    DEFF Research Database (Denmark)

    Ullidtz, Per

    This textbook is primarily concerned with models for predicting the future condition of flexible pavements, as a function of traffic loading, climate, materials, etc., using analytical-empirical methods.......This textbook is primarily concerned with models for predicting the future condition of flexible pavements, as a function of traffic loading, climate, materials, etc., using analytical-empirical methods....

  6. Field cracking performance of airfield rigid pavements

    Directory of Open Access Journals (Sweden)

    Yusuf Mehta

    2017-08-01

    Full Text Available This paper discusses cracking in airport pavements as studied in Construction Cycle 6 of testing carried out at the National Airport Pavement Testing Facility by the Federal Aviation Administration. Pavements of three different flexural strengths as well as two different subgrades, a soft bituminous layer and a more rigid layer known as econocrete, were tested. In addition to this, cracking near two types of isolated transition joints, a reinforced edge joint and a thickened edge joint, was considered. The pavement sections were tested using a moving load simulating that of an aircraft. It has been determined that the degree of cracking was reduced as the flexural strength of the pavement was increased and that fewer cracks formed over the econocrete base than over the bituminous base. In addition, the thickened edge transition joint was more effective in preventing cracking at the edges compared to the reinforced edge joint.

  7. Fatigue and rutting lives in flexible pavement

    Directory of Open Access Journals (Sweden)

    Ahmed Ebrahim Abu El-Maaty Behiry

    2012-12-01

    Full Text Available Flexible pavement is designed based on axle load limits and climatic conditions. The Egyptian code has specified certain load limits that should not be exceeded. The overweight trucks cause severe deterioration to the pavement and thus reduce its life. The study aims at studying the effect of axle load increase, and the variation in pavement modulus, on the overall pavement life. The research uses the BISAR software and the Egyptian environmental and pavement materials conditions to estimate the tensile strains occurring under the asphalt concrete (AC layer and the compressive strains above the subgrade surface. The results revealed that tensile and compressive strain increased with increasing axle loads and decreased with increasing asphalt layer modulus thus the violating trucks should be unloaded when their weights exceed certain limits. Base thickness and subgrade resilient modulus were the key elements which control the equilibrium between fatigue and rutting lives.

  8. Theoretical Relationships Between Moduli for Soil Layers Beneath Concrete Pavements.

    Science.gov (United States)

    method of analysis used for rigid pavements and the elastic layer method of analysis used for both rigid and flexible pavements. Twenty-three pavement sections were selected to illustrate the usage of these relationships. These sections represent the widest possible variation of rigid pavement types for which sufficient materials data was available. For the sections studied and within the context of linear analysis, these relationships demonstrate that the peak pavement stress can usually be computed by either method

  9. Performance-Based Evaluation of Joint Sealants for Concrete Pavements

    OpenAIRE

    Khuri, Ramzi Emile

    1998-01-01

    Pavement concrete joints are the weakest locations in concrete pavement systems. They are man-made cracks to accommodate concrete slab expansion and contraction due to temperature fluctuations. Sealant is usually used in pavement joints to prevent roadway debris, deicing chemicals, and moisture from entering the joint. When sealant fails, the pavement deteriorates rapidly; and when joint sealant performs adequately, the pavement preserves its intended performance. In the field, joint seala...

  10. Side Effects: Bleeding and Bruising

    Science.gov (United States)

    Cancer treatments, such as chemotherapy and targeted therapy, can increase patients’ risk of bleeding and bruising, also called thrombocytopenia. Learn about steps to take if you are at increased risk of a low platelet count.

  11. Quantifying Evaporation in a Permeable Pavement System ...

    Science.gov (United States)

    Studies quantifying evaporation from permeable pavement systems are limited to a few laboratory studies and one field application. This research quantifies evaporation for a larger-scale field application by measuring the water balance from lined permeable pavement sections. The U.S. Environmental Protection Agency (USEPA) constructed a 0.4-ha parking lot in Edison, NJ, that incorporated three different permeable pavement types in the parking lanes – permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA). An impermeable liner installed 0.4 m below the driving surface in four 11.6-m by 4.74-m sections per each pavement type captures all infiltrating water and routes it to collection tanks that can contain events up to 38 mm. Each section has a design impervious area to permeable pavement area ratio of 0.66:1. Pressure transducers installed in the underdrain collection tanks measured water level for 24 months. Level was converted to volume using depth-to-volume ratios for individual collection tanks. Using a water balance approach, the measured infiltrate volume was compared to rainfall volume on an event-basis to determine the rainfall retained in the pavement strata and underlying aggregate. Evaporation since the previous event created additional storage in the pavement and aggregate layers. Events were divided into three groups based on antecedent dry period (ADP) and three, four-month categories of potential e

  12. Assessment of highway pavements using GPR

    Science.gov (United States)

    Plati, Christina; Loizos, Andreas

    2015-04-01

    Highway infrastructure is a prerequisite for a functioning economy and social life. Highways, often prone to congestion and disruption, are one of the aspects of a modern transport network that require maximum efficiency if an integrated transport network, and sustainable mobility, is to be achieved. Assessing the condition of highway structures, to plan subsequent maintenance, is essential to allow the long-term functioning of a road network. Optimizing the methods used for such assessment will lead to better information being obtained about the road and underlying ground conditions. The condition of highway structures will be affected by a number of factors, including the properties of the highway pavement, the supporting sub-base and the subgrade (natural ground), and the ability to obtain good information about the entire road structure, from pavement to subgrade, allows appropriate maintenance programs to be planned. The maintenance of highway pavements causes considerable cost and in many cases obstruction to traffic flow. In this situation, methods that provide information on the present condition of pavement structure non-destructively and economically are of great interest. It has been shown that Ground-Penetrating-Radar (GPR), which is a Non Destructive Technique (NDT), can deliver information that is useful for the planning of pavement maintenance activities. More specifically GPR is used by pavement engineers in order to determine physical properties and characteristics of the pavement structure, information that is valuable for the assessment of pavement condition. This work gives an overview on the practical application of GPR using examples from highway asphalt pavements monitoring. The presented individual applications of GPR pavement diagnostics concern structure homogeneity, thickness of pavement layers, dielectric properties of asphalt materials etc. It is worthwhile mentioning that a number of applications are standard procedures, either

  13. User's guide : pavement marking management system database.

    Science.gov (United States)

    2011-12-01

    Pavement markings play a critical role in maintaining a safe and efficient driving environment for road users, especially during nighttime conditions. The Texas Department of Transportation (TxDOT) spends millions of dollars each year for installatio...

  14. Permeable Pavement Research - Edison, New Jersey

    Science.gov (United States)

    This presentation provides the background and summary of results collected at the permeable pavement parking lot monitored at the EPA facility in Edison, NJ. This parking lot is surfaced with permeable interlocking concrete pavers (PICP), pervious concrete, and porous asphalt. ...

  15. Class C fly ash in pavements.

    Science.gov (United States)

    2010-07-01

    Portland cement is the most dominant material used in concrete pavements in the state of Nebraska. In order to improve performance, reduce cost, and advance sustainability, a percentage of the Portland cement is replaced with a recycled material know...

  16. Performance of I-57 recycled concrete pavements.

    Science.gov (United States)

    2009-01-01

    In 1986-1987 the Illinois Department of Transportation (IDOT) constructed a demonstration project on I-57 near Effingham, Illinois to evaluate the viability : of recycling an existing jointed reinforced concrete pavement for use as its primary aggreg...

  17. Pervious Pavement System Evaluation- Abstract 1

    Science.gov (United States)

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, gra...

  18. Long term monitoring of moisture under pavements.

    Science.gov (United States)

    2010-01-01

    Monitoring of the environmental instrumentation installed under select pavement sections constructed : by the Ohio Department of Transportation (ODOT) in 1995 on US 23 in Delaware County, Ohio was : continued. The measurements made consisted of soil ...

  19. Concrete pavement construction basics : tech notes.

    Science.gov (United States)

    2006-08-01

    This tech note has been produced for developers, consultants, and engineers planning concrete pavement construction projects, superintendents and supervisors who want a basic training aid and reference, and crew members new to the concrete paving ind...

  20. Noise measurements of highway pavements in Texas.

    Science.gov (United States)

    2009-10-01

    This report presents the results of noise testing performed on Texas pavements between May of 2006 and the : summer of 2008. Two field test methodologies were used: roadside noise measurement with SPL meters and onvehicle : sound intensity measuremen...

  1. Improving safety in pavement field testing.

    Science.gov (United States)

    2017-09-15

    The Florida Department of Transportation (FDOT) collects pavement condition and performance data each year, using both site-specific equipment that requires temporary traffic control (TTC) operations (either moving or closed operations) and full-size...

  2. Reformulated pavement remaining service life framework.

    Science.gov (United States)

    2013-11-01

    "Many important decisions are necessary in order to effectively provide and manage a pavement network. At the heart : of this process is the prediction of needed future construction events. One approach to providing a single numeric on : the conditio...

  3. Optimization of safety on pavement preservation projects.

    Science.gov (United States)

    2011-01-01

    To achieve a goal of reducing highway crash fatalities by 4% each year to improve roadway safety, the Georgia Department of Transportation (GDOT) is actively seeking opportunities to incorporate safety improvements into its current pavement preservat...

  4. On-road Bicycle Pavement Markings

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — A mile by mile breakdown of the on-street bicycle pavement markings installed within the City of Pittsburgh. These include bike lanes, shared lane markings...

  5. Revision of South African pavement design method

    CSIR Research Space (South Africa)

    Kannemeyer, L

    2015-08-01

    Full Text Available South Africa has a long pavement engineering history in terms of developing methodologies and solutions for supporting the local economy using available materials under specific environmental and socio-economic conditions. Over the past 10 years...

  6. Mechanistic flexible pavement overlay design program.

    Science.gov (United States)

    2009-07-01

    The current Louisiana Department of Transportation and Development (LADOTD) overlay thickness design method follows the Component : Analysis procedure provided in the 1993 AASHTO pavement design guide. Since neither field nor laboratory tests a...

  7. Life cycle assessment of asphalt pavement maintenance.

    Science.gov (United States)

    2014-01-01

    This study aims at developing a life cycle assessment (LCA) model to quantify the impact of pavement preservation on energy consumption and greenhouse gas (GHG) emissions. The construction stage contains material, manufacture, transportation and plac...

  8. Performance evaluation of precast prestressed concrete pavement.

    Science.gov (United States)

    2007-11-01

    This report describes in detail an experimental investigation of an innovative precast prestressed concrete pavement (PPCP) system used to rehabilitate a 1,000 ft. section of interstate highway located on the northbound lanes of I-57 near Charleston,...

  9. Development of Pavement Condition Index Model Using PAVER 6.5.7 for Flexible Pavement Urban Roads in Kerbala City

    OpenAIRE

    Hussein Ali Ewadh; Raid Rahman Almuhanna; Saja Jasim Alasadi

    2017-01-01

    The pavement condition index (PCI) is an important factor indicating pavement condition of roads. The pavement is one of the basic parts of the road infrastructure. Accordingly the aim of this paper is to develop a pavement condition index model using PAVER 6.5.7 for a flexible pavement urban roads in the Kerbala city center. The development model is depending on the PCI value of 109 sample sections having 57.8 km length, Data collected for pavement distress (type, dimension, and severity) w...

  10. Fusing complementary images for pavement cracking measurements

    International Nuclear Information System (INIS)

    Yao, Ming; Zhao, Zuyun; Xu, Bugao; Yao, Xun

    2015-01-01

    Cracking is a major pavement distress that jeopardizes road serviceability and traffic safety. Automated pavement distress survey (APDS) systems have been developed using digital imaging technology to replace human surveys for more timely and accurate inspections. Most APDS systems require special lighting devices to illuminate pavements and prevent shadows of roadside objects that distort cracks in the image. Most artificial lighting devices are laser based, and are either hazardous to unprotected people or require dedicated power supplies on the vehicle. This study was aimed to develop a new imaging system that can scan pavement surface at highway speed and determine the level of severity of pavement cracking without using any artificial lighting. The new system consists of dual line-scan cameras that are installed side by side to scan the same pavement area as the vehicle moves. Cameras are controlled with different exposure settings so that both sunlit and shadowed areas can be visible in two separate images. The paired images contain complementary details useful for reconstructing an image in which the shadows are eliminated. This paper intends to present (1) the design of the dual line-scan camera system, (2) a new calibration method for line-scan cameras to rectify and register paired images, (3) a customized image-fusion algorithm that merges the multi-exposure images into one shadow-free image for crack detection, and (4) the results of the field tests on a selected road over a long period. (paper)

  11. Coagulation management in massive bleeding.

    Science.gov (United States)

    Griffee, Matthew J; Deloughery, Thomas G; Thorborg, Per A

    2010-04-01

    To update readers on recent literature regarding treatment of coagulopathy for patients with life-threatening bleeding, highlighting emerging therapeutic options, controversial topics, and ongoing clinical trials. Massive transfusion protocols featuring immediate availability of blood products and multidisciplinary communication reduce mortality and conserve resources. There is a growing consensus that immediate administration of plasma and platelet units in a 1: 1: 1 ratio with red cell units reduces early mortality. Lyophilized and recombinant blood product components may have advantages over traditional blood products in certain clinical circumstances. Massive transfusion protocols standardize treatment of the coagulopathy of massive bleeding, leading to rapid restoration of hemostasis and decrease in early mortality.

  12. Managing oral bleeding in children with hereditary bleeding disorders

    African Journals Online (AJOL)

    All the patients presented with bleeding gingivae secondary to either physiologic processes of eruption, infective or traumatic dental conditions. The management of the patients was comprehensive with a multidisciplinary approach. The prevention of traumatic and infective dental conditions is an important part of oral health ...

  13. Thermal stability analysis under embankment with asphalt pavement and cement pavement in permafrost regions.

    Science.gov (United States)

    Junwei, Zhang; Jinping, Li; Xiaojuan, Quan

    2013-01-01

    The permafrost degradation is the fundamental cause generating embankment diseases and pavement diseases in permafrost region while the permafrost degradation is related with temperature. Based on the field monitoring results of ground temperature along G214 Highway in high temperature permafrost regions, both the ground temperatures in superficial layer and the annual average temperatures under the embankment were discussed, respectively, for concrete pavements and asphalt pavements. The maximum depth of temperature field under the embankment for concrete pavements and asphalt pavements was also studied by using the finite element method. The results of numerical analysis indicate that there were remarkable seasonal differences of the ground temperatures in superficial layer between asphalt pavement and concrete pavement. The maximum influencing depth of temperature field under the permafrost embankment for every pavement was under the depth of 8 m. The thawed cores under both embankments have close relation with the maximum thawed depth, the embankment height, and the service time. The effective measurements will be proposed to keep the thermal stabilities of highway embankment by the results.

  14. Thermal Stability Analysis under Embankment with Asphalt Pavement and Cement Pavement in Permafrost Regions

    Directory of Open Access Journals (Sweden)

    Zhang Junwei

    2013-01-01

    Full Text Available The permafrost degradation is the fundamental cause generating embankment diseases and pavement diseases in permafrost region while the permafrost degradation is related with temperature. Based on the field monitoring results of ground temperature along G214 Highway in high temperature permafrost regions, both the ground temperatures in superficial layer and the annual average temperatures under the embankment were discussed, respectively, for concrete pavements and asphalt pavements. The maximum depth of temperature field under the embankment for concrete pavements and asphalt pavements was also studied by using the finite element method. The results of numerical analysis indicate that there were remarkable seasonal differences of the ground temperatures in superficial layer between asphalt pavement and concrete pavement. The maximum influencing depth of temperature field under the permafrost embankment for every pavement was under the depth of 8 m. The thawed cores under both embankments have close relation with the maximum thawed depth, the embankment height, and the service time. The effective measurements will be proposed to keep the thermal stabilities of highway embankment by the results.

  15. How to reduce tire-pavement noise : better practices for constructing and texturing concrete pavement surfaces.

    Science.gov (United States)

    2012-08-01

    Concrete pavements can be designed and constructed to be as quiet as any other conventional pavement type in use today. This report : provides an overview of how this can be doneand done consistently. : In order to construct a quieter concrete pav...

  16. Demonstration of using quieter pavement in Death Valley National Park

    Science.gov (United States)

    2013-06-01

    Death Valley National Park provided an environment that allowed a demonstration of : quieter pavement use. Sound measurements near the tire-pavement interface, near the : road, and in areas of frequent human use were conducted and analyses performed ...

  17. Continuous real time measurement of pavement quality during construction.

    Science.gov (United States)

    2010-12-01

    Intelligent Compaction has been investigated as a means of improving the quality of asphalt pavements during their : construction. The long term performance of an asphalt pavement is directly related to its load bearing capability and : is determined...

  18. Laboratory fatigue evaluation of continuously fiber-reinforced concrete pavement.

    Science.gov (United States)

    2013-09-01

    Portland cement concrete (PCC) is the worlds most versatile construction material. PCC has : been in use in the United States for over 100 years. PCC pavement is generally constructed as : either continually reinforced concrete pavement (CRCP) or ...

  19. Evaluation of recycled concrete as aggregate in new concrete pavements.

    Science.gov (United States)

    2014-04-01

    This study evaluated the use of recycled concrete as coarse aggregate in new concrete pavements. : Recycled concrete aggregate (RCA) produced from demolished pavements in three geographically dispersed locations in Washington state were used to perfo...

  20. Mobile geographic information system solution for pavement condition surveys [summary].

    Science.gov (United States)

    2012-01-01

    The State Materials Office (SMO) of the Florida : Department of Transportation (FDOT) performs : annual Pavement Condition Surveys (PCS) of : the Departments extensive pavement network. : This work is performed by single-person crews in : inertial...

  1. Guidelines for PCC inputs to AASHTOWare Pavement ME.

    Science.gov (United States)

    2014-12-01

    The objective of this research study was to develop guidelines for portland cement concrete (PCC) material inputs to the : AASHTOWare Pavement ME Design program. The AASHTOWare Pavement ME Design is the software program used by the : Mississippi Depa...

  2. Long term pavement performance computed parameter : frost penetration

    Science.gov (United States)

    2008-11-01

    As the pavement design process moves toward mechanistic-empirical techniques, knowledge of seasonal changes in pavement structural characteristics becomes critical. Specifically, frost penetration information is necessary for determining the effect o...

  3. Predicting low-temperature cracking in asphalt pavements : [research brief].

    Science.gov (United States)

    2011-12-01

    In Wisconsin's winter climate, low temperatures can cause asphalt pavements to contract and crack, reducing their ride quality and service lives. To help engineers more accurately determine how well certain pavement designs will fare in such conditio...

  4. Effect of friction on rolling tire-pavement interaction

    Science.gov (United States)

    2010-11-01

    In this research, a three-dimensional (3-D) tire-pavement interaction model is developed using FEM to analyze the tire-pavement contact stress distributions at various rolling conditions (free rolling, braking/accelerating, and cornering). In additio...

  5. Precision and accuracy of mechanistic-empirical pavement design

    CSIR Research Space (South Africa)

    Theyse, HL

    2006-09-01

    Full Text Available The availability of mechanistic-empirical pavement design methods is increasing internationally. Although mechanistic-empirical design does offer some insight into pavement behaviour and performance, at least more so than empirical design methods...

  6. Advanced Automated Detection Analysis and Classification of Cracks in Pavement

    OpenAIRE

    Scott, Dennis

    2014-01-01

    Functional Session 5: Pavement Management Moderated by Akyiaa Hosten This presentation was held at the Pavement Evaluation 2014 Conference, which took place from September 15-18, 2014 in Blacksburg, Virginia. Presentation only

  7. Investigation clogging dynamic of permeable pavement systems using embedded sensors

    Science.gov (United States)

    Permeable pavement is a stormwater control measure commonly selected in both new and retrofit applications. However, there is limited information about the clogging mechanism of these systems that effects the infiltration. A permeable pavement site located at the Seitz Elementary...

  8. Performance and cost effectiveness of permeable friction course (PFC) pavements.

    Science.gov (United States)

    2013-02-01

    In this project, the research team evaluated the performance of Permeable Friction Courses (PFC) over time and compared it against other types of wearing surface pavement layers. Several pavement sections including Asphalt Rubber (AR) PFCs, Performan...

  9. Overlay design method based on visual pavement distress.

    Science.gov (United States)

    1978-01-01

    A method for designing the thickness of overlays for bituminous concrete pavements in Virginia is described. In this method the thickness is calculated by rating the amount and severity of observed pavement distress and determining the total accumula...

  10. Mechanistic flexible pavement overlay design program : tech summary.

    Science.gov (United States)

    2009-07-01

    The Louisiana Department of Transportation and Development (LADOTD) currently follows the 1993 : AASHTO pavement design guides component analysis method in its fl exible pavement overlay thickness : design. Such an overlay design method, how...

  11. Software offers transparent, straightforward assessment of pavement additives : research spotlight.

    Science.gov (United States)

    2015-04-01

    Adding new materials to pavement layers is a proven technique to : improve performance. Many types of additivesfrom engineered : polymers and acids to recycled pavement, crumb rubber, shingles : and glasshave been used to help construct better ...

  12. AASHTO mechanistic-empirical pavement design guide parametric study.

    Science.gov (United States)

    2012-03-01

    This study focuses on assessing the robustness of the AASHTO Mechanistic-Empirical Pavement Design Guide (MEPDG v 1.1) for rigid pavement : design projects in Wisconsin. The primary tasks conducted in this study included performing sensitivity analys...

  13. Overview of the South African mechanistic pavement design analysis method

    CSIR Research Space (South Africa)

    Theyse, HL

    1996-01-01

    Full Text Available A historical overview of the South African mechanistic pavement design method, from its development in the early 1970s to the present, is presented. Material characterization, structural analysis, and pavement life prediction are discussed...

  14. Evaluating the performance of sustainable perpetual pavements using recycled asphalt pavement in China

    Directory of Open Access Journals (Sweden)

    Saud A. Sultan

    2016-10-01

    Full Text Available The vast highways network in China is moving from the phase of construction to the phase of maintenance, and with the introduction of new technique of perpetual pavement in last decade, it is necessary to consider recycling as one of the promising solutions for rehabilitation of old asphalt concrete pavement and ultimately to convert them into perpetual pavements. The aim is to reuse the existing pavement materials for several reasons, mainly to preserve natural resources such as aggregates, and to satisfy economic requirements by reducing the cost of highway construction and rehabilitation. A detailed testing program has been carried out on recycled asphalt pavements materials (RAP to evaluate their mechanical and structural characteristics to be used for the construction and rehabilitation of road pavements. Different types of RAP mixes have been stabilized by Portland cement to find the most suitable one from the point of view of design, construction, economy and environment. The analysis of life cycle costs has been carried out using system analysis and management of pavement program (SAMP5. The analysis of life cycle costs showed that the use of Portland cements with small percentages improves the structural characteristics of recycled asphalt materials to be used as stabilized base pavement layers for new or rehabilitated old road pavements and also for the construction and rehabilitation of perpetual pavements. A large amount of savings in construction and rehabilitation cost has been achieved by the use of stabilized RAP materials in addition to important contributions to the environment and preserving of natural resources.

  15. Predictors of bleeding during heparin therapy.

    Science.gov (United States)

    Walker, A M; Jick, H

    1980-09-12

    Among 2,656 patients receiving heparin sodium therapy, bleeding was a dose-related phenomenon that occurred most commonly among women, severely ill patients, and patients who received asprin during heparin therapy. Except for dose, factors that predisposed patients to bleeding were more strongly associated with major bleeding than with minor bleeding. Heavy alcohol drinkers were at particularly high risk for major bleeding episodes during heparinization. The seven-day cumulative risk for any bleeding was 9.1%. Risk was greatest on the third day of heparin administration.

  16. Management of bleeding gastroduodenal ulcers

    DEFF Research Database (Denmark)

    Laursen, Stig Borbjerg; Jørgensen, Henrik Stig; Schaffalitzky de Muckadell, Ove B.

    2012-01-01

    -risk stigmata. Although selected patients can be discharged promptly after endoscopy, high-risk patients should be hospitalized for at least 3 days after endoscopic hemostasis. Patients with peptic ulcer bleeding who require secondary cardiovascular prophylaxis should start receiving acetylsalicylic acid (ASA...

  17. Abnormal uterine bleeding in perimenopause.

    Science.gov (United States)

    Goldstein, S R; Lumsden, M A

    2017-10-01

    Abnormal uterine bleeding is one of the commonest presenting complaints encountered in a gynecologist's office or primary-care setting. The wider availability of diagnostic tools has allowed prompt diagnosis and treatment of an increasing number of menstrual disorders in an office setting. This White Paper reviews the advantages and disadvantages of transvaginal ultrasound, blind endometrial sampling and diagnostic hysteroscopy. Once a proper diagnosis has been established, appropriate therapy may be embarked upon. Fortunately, only a minority of such patients will have premalignant or malignant disease. When bleeding is sufficient to cause severe anemia or even hypovolemia, prompt intervention is called for. In most of the cases, however, the abnormal uterine bleeding will be disquieting to the patient and significantly affect her 'quality of life'. Sometimes, reassurance and expectant management will be sufficient in such patients. Overall, however, in cases of benign disease, some intervention will be required. The use of oral contraceptive pills especially those with a short hormone-free interval, the insertion of the levonorgestrel intrauterine system, the incorporation of newer medical therapies including antifibrinolytic drugs and selective progesterone receptor modulators and minimally invasive treatments have made outpatient therapy increasingly effective. For others, operative hysteroscopy and endometrial ablation are proven therapeutic tools to provide both long- and short-term relief of abnormal uterine bleeding, thus avoiding, or deferring, hysterectomy.

  18. Evaluation of Procedures for Backcalculation of Airfield Pavement Moduli

    Science.gov (United States)

    2015-08-01

    surface and the base pavement is positively in good condition Cb = 0.8 if only reflective cracks or only joint reflective cracks are present on...backcalculation routine with the real pavement scenario.  Testing in proximity of cracks or joints results in measured deflection basins that... pavement (JPCP) 1 Plant mix (emulsified asphalt) material, cold-laid 20 Jointed reinforced concrete pavement (JRCP) 1 Cracked and seated PCC

  19. Pavement Condition Survey in Kagawa Prefecture using ROMDAS

    OpenAIRE

    Mohammad, Mamunur Rashid; 角川, 浩二

    2006-01-01

    Highway is one of the most important areas among the various facilities of infrastructure. Therefore, most of the organizations related to the infrastructure management system pay higher attention to the pavement which is the most important facility of highway management. An effective pavement management system (PMS) helps to carry out all the preservation and necessary maintenance operations of the pavement. In order to implement a pavement management system, data collection that indicates e...

  20. A fuzzy logic approach for pavement section classification

    OpenAIRE

    Mahmood, M; Rahman, M; Nolle, L; Mathavan, S

    2013-01-01

    Section classification is one of the primary challenges in any successful pavement management system. Sections are normally classified based on their pavement condition index in order to categorise as "good", "moderate" and "poor". Conventionally, this has been done by comparing various pavement distress data against threshold values. However, borderline values between two categories have significant influence on the subsequent pavement maintenance and rehabilitation decision. This study is t...

  1. AutoPAVER: A software package for automated pavement evaluation

    Science.gov (United States)

    Ginsberg, Mark D.; Shahin, M. Y.; Walther, Jeanette A.

    1990-07-01

    This research developed a method that improves data collection and reduces data entry times for Pavement Condition Index (PCI) surveys for use with PAVER, a pavement maintenance management system. The method, AutoPAVER, is a microcomputer software package used to analyze pictures of pavement surfaces and to forward the resulting analysis to PAVER. The user works interactively with the system to identify and classify pavement distresses. Distress measurement and data entry are done on the computer.

  2. Pavement Condition Survey in Kagawa Prefecture using ROMDAS

    OpenAIRE

    Mohammad Mamunur Rashid; 角川, 浩二

    2005-01-01

    Highway is one of the most important areas among the various facilities of infrastructure. Therefore, most of the organizations related to the infrastructure management system pay higher attention to the pavement which is the most important facility of highway management. An effective pavement management system (PMS) helps to carry out all the preservation and necessary maintenance operations of the pavement. In order to implement a pavement management system, data collection that indicates e...

  3. Precast concrete pavement - systems and performance review

    Science.gov (United States)

    Novak, Josef; Kohoutková, Alena; Křístek, Vladimír; Vodička, Jan

    2017-09-01

    Long-term traffic restrictions belong to the key disadvantages of conventional cast-in-plane concrete pavements which have been used for technical structures such as roads, parking place and airfield pavements. As a consequence, the pressure is put on the development of such systems which have short construction time, low production costs, long-term durability, low maintenance requirements etc.. The paper presents the first step in the development of an entirely new precast concrete pavement (PCP) system applicable to airfield and highway pavements. The main objective of the review of PCP systems is to acquire a better understanding of the current systems and design methods used for transport infrastructure. There is lack of information on using PCP systems for the construction of entirely new pavements. To most extensive experience is dated back to the 20th century when hexagonal slab panels and system PAG were used in the Soviet Union for the military airfields. Since cast-in-situ pavements became more common, the systems based on precast concrete panels have been mainly utilized for the removal of damaged sections of existing structures including roads, highways etc.. Namely, it concerns Fort Miller Super Slab system, Michigan system, Uretek Stitch system and Kwik system. The presented review indicates several issues associated with the listed PCP systems and their applications to the repair and rehabilitation of existing structures. Among others, the type of manufacturing technology, particularly the position of slots for dowel bars, affects the durability and performance of the systems. Gathered information serve for the development of a new system for airfield and highway pavement construction.

  4. Design and construction of PCC pavements. Volume 2, design features and practices that influence performance of pavements

    Science.gov (United States)

    1998-10-01

    A study has been conducted to evaluate and analyze Portland cement concrete (PCC) pavements in order to develop recommendations for the design and construction of long-lived concrete pavements. In involved a detailed evaluation and analysis of the PC...

  5. Design and construction of PCC pavements, volume 2 : design features and practices that influence performance of pavements.

    Science.gov (United States)

    1998-10-01

    A study has been conducted to evaluate and analyze portland cement concrete (PCC) pavements in order to : develop recommendations for the design and construction of long-lived concrete pavements. It involved a : detailed evaluation and analysis of th...

  6. Design and construction of PCC pavements. Volume 1, summary of design features and construction practices that influence performance of pavements

    Science.gov (United States)

    1998-04-01

    A study has been conducted to evaluate and analyze Portland cement concrete (PCC) pavements in order to develop recommendations for the design and construction of long-lived concrete pavements. In involved a detailed evaluation and analysis of the PC...

  7. Evaluation of current Louisiana flexible pavement structures using PMS data and new mechanistic-empirical pavement design guide : tech summary.

    Science.gov (United States)

    2012-04-01

    The new Mechanistic-Empirical Pavement Design Guide (MEPDG) developed under the National Cooperative Highway : Research Program (NCHRP) Project 1-37A represents a major change as compared to the 1993 AASHTO Pavement : Design Guide. MEPDG provides a r...

  8. Evaluation of current Louisiana flexible pavement structures using PMS data and new M-E pavement design guide.

    Science.gov (United States)

    2010-10-01

    The proposed study uses the new MEPDG together with data available from LADOTDs Pavement Management System (PMS) and other data sources from LADOTDs main frame to evaluate typical flexible pavement structures currently used and to make changes ...

  9. Spontaneous Bleeding Associated with Ginkgo biloba

    Science.gov (United States)

    Bent, Stephen; Goldberg, Harley; Padula, Amy; Avins, Andrew L

    2005-01-01

    BACKGROUND Ginkgo biloba (ginkgo) is a herbal remedy used by over 2% of the adult population in the United States. Several review articles have suggested that ginkgo may increase the risk of bleeding. OBJECTIVE To report a case of bleeding associated with using ginkgo, to systematically review the literature for similar case reports, and to evaluate whether using ginkgo is causally related to bleeding. DATA SOURCES We searched MEDLINE, EMBASE, IBIDS, and the Cochrane Collaboration Database from 1966 to October 2004 with no language restrictions. REVIEW METHODS Published case reports of bleeding events in persons using ginkgo were selected. Two reviewers independently abstracted a standard set of information to assess whether ginkgo caused the bleeding event. RESULTS Fifteen published case reports described a temporal association between using ginkgo and a bleeding event. Most cases involved serious medical conditions, including 8 episodes of intracranial bleeding. However, 13 of the case reports identified other risk factors for bleeding. Only 6 reports clearly described that ginkgo was stopped and that bleeding did not recur. Bleeding times, measured in 3 reports, were elevated when patients were taking ginkgo. CONCLUSION A structured assessment of published case reports suggests a possible causal association between using ginkgo and bleeding events. Given the widespread use of this herb and the serious nature of the reported events, further studies are needed. Patients using ginkgo, particularly those with known bleeding risks, should be counseled about a possible increase in bleeding risk. PMID:16050865

  10. Knowledge Discovery and Pavement Performance : Intelligent Data Mining

    NARCIS (Netherlands)

    Miradi, M.

    2009-01-01

    The main goal of the study was to discover knowledge from data about asphalt road pavement problems to achieve a better understanding of the behavior of them and via this understanding improve pavement quality and enhance its lifespan. Four pavement problems were chosen to be investigated; raveling

  11. Estimating the benefits of improved drainage on pavement ...

    African Journals Online (AJOL)

    The drainage quality is an important parameter which affects the performance of highway pavements. In India, since last few years considerable importance has been given to the drainage as per of pavement. A poor quality of drainage results in premature deterioration of the pavement structure and necessitating large ...

  12. Effect of training algorithms on neural networks aided pavement ...

    African Journals Online (AJOL)

    Routine pavement maintenance necessitates present structural diagnosis and condition evaluation of pavements by employing non-destructive test equipment such as the Falling Weight Deflectometer (FWD). FWD testing of pavements involves measuring time-domain surface deflections resulting from applied impulse ...

  13. Effect of age of permeable pavements on their infiltration function

    NARCIS (Netherlands)

    Terry Lucke; ir. Floris Boogaard; Simon Beecham

    2013-01-01

    This study describes field investigations designed to compare the infiltration capacities of 55 permeable pavement systems installed in the Netherlands and in Australia. The ages of the pavements varied from 1 to 12 years. Using infiltrometer testing, the performance of the pavements has been

  14. Future design of perpetual pavements for New Mexico.

    Science.gov (United States)

    2009-12-29

    This study provides guidance for future designs of perpetual pavements in New Mexico. The perpetual pavement in this study refers to only hot mix asphalt (HMA) pavement sections designed for a useful life of 50 years or more without having major dist...

  15. Pavement sound absorption measurements in the U.S.

    Science.gov (United States)

    2012-08-19

    In the U.S., the topic of pavement sound absorption in regard to tire-pavement noise has shown increased interest and research over the last several years. Four types of pavement sound absorption measurements with various applications are discussed: ...

  16. Effectiveness of various public private partnership pavement rehabilitation treatments: A big data informatics survival analysis of pavement service life : final report.

    Science.gov (United States)

    2017-09-29

    Past research efforts have used a wide variety of methodological approaches to analyze pavement performance indicators, pavement rehabilitation treatments, and pavement service life. Using big data informatics methods, the intent of this study is to ...

  17. Vitamin K deficiency bleeding of the newborn

    Science.gov (United States)

    Vitamin K deficiency bleeding of the newborn (VKDB) is a bleeding disorder in babies. It most often develops shortly ... A lack of vitamin K may cause severe bleeding in newborn babies. Vitamin K plays an important role in blood clotting. Babies often have a ...

  18. Gastrointestinal Bleeding Secondary to Calciphylaxis

    Science.gov (United States)

    Gupta, Nancy; Haq, Khwaja F.; Mahajan, Sugandhi; Nagpal, Prashant; Doshi, Bijal

    2015-01-01

    Patient: Female, 66 Final Diagnosis: Calciphylaxis Symptoms: Gastrointesinal haemorrhage Medication: None Clinical Procedure: Hemodialysis • blood transfusions Specialty: Gastroenterology and Hepatology Objective: Rare disease Background: Calciphylaxis is associated with a high mortality that approaches 80%. The diagnosis is usually made when obvious skin lesions (painful violaceous mottling of the skin) are present. However, visceral involvement is rare. We present a case of calciphylaxis leading to lower gastrointestinal (GI) bleeding and rectal ulceration of the GI mucosa. Case Report: A 66-year-old woman with past medical history of diabetes mellitus, hypertension, end-stage renal disease (ESRD), recently diagnosed ovarian cancer, and on hemodialysis (HD) presented with painful black necrotic eschar on both legs. The radiograph of the legs demonstrated extensive calcification of the lower extremity arteries. The hospital course was complicated with lower GI bleeding. A CT scan of the abdomen revealed severe circumferential calcification of the abdominal aorta, celiac artery, and superior and inferior mesenteric arteries and their branches. Colonoscopy revealed severe rectal necrosis. She was deemed to be a poor surgical candidate due to comorbidities and presence of extensive vascular calcifications. Recurrent episodes of profuse GI bleeding were managed conservatively with blood transfusion as needed. Following her diagnosis of calciphylaxis, supplementation with vitamin D and calcium containing phosphate binders was stopped. She was started on daily hemodialysis with low calcium dialysate bath as well as intravenous sodium thiosulphate. The clinical condition of the patient deteriorated. The patient died secondary to multiorgan failure. Conclusions: Calciphylaxis leading to intestinal ischemia/perforation should be considered in the differential diagnosis in ESRD on HD presenting with abdominal pain or GI bleeding. PMID:26572938

  19. Antifibrinolytics for heavy menstrual bleeding.

    Science.gov (United States)

    Lethaby, A; Farquhar, C; Cooke, I

    2000-01-01

    Heavy menstrual bleeding (HMB) is an important cause of ill health in women. Medical therapy, with the avoidance of possibly unnecessary surgery, is an attractive treatment option. A wide variety of medications are available to reduce heavy menstrual bleeding but there is considerable variation in practice and uncertainty about the most appropriate therapy. Plasminogen activators are a group of enzymes that cause fibrinolysis (the dissolution of clots). An increase in the levels of plasminogen activators has been found in the endometrium of women with heavy menstrual bleeding compared to those with normal menstrual loss. Plasminogen activator inhibitors (antifibrinolytic agents) have therefore been promoted as a treatment for heavy menstrual bleeding. There has been a reluctance to prescribe tranexamic acid due to possible side effects of the drugs such as an increased risk of thrombogenic disease (deep venous thrombosis). Long term studies in Sweden, however, have shown that the rate of incidence of thrombosis in women treated with tranexamic acid is comparable with the spontaneous frequency of thrombosis in women. To determine the effectiveness of antifibrinolytics in achieving a reduction in heavy menstrual bleeding. All studies which might describe randomised controlled trials of antifibrinolytic therapy for the treatment of heavy menstrual bleeding were obtained by electronic searches of MEDLINE 1966-1997, EMBASE 1980-1997 and the Cochrane Library. Companies producing antifibrinolytics and experts within the field were contacted for reference lists and information on unpublished trials. Randomised controlled trials in women of reproductive age treated with antifibrinolytic agents versus placebo, no treatment or any other medical (non-surgical) therapy for regular heavy menstrual bleeding within either the primary, family planning or specialist clinic settings. Women with post menopausal bleeding, intermenstrual bleeding, iatrogenic or pathological causes of

  20. Optical microtopographic inspection of asphalt pavement surfaces

    Science.gov (United States)

    Costa, Manuel F. M.; Freitas, E. F.; Torres, H.; Cerezo, V.

    2017-08-01

    Microtopographic and rugometric characterization of surfaces is routinely and effectively performed non-invasively by a number of different optical methods. Rough surfaces are also inspected using optical profilometers and microtopographer. The characterization of road asphalt pavement surfaces produced in different ways and compositions is fundamental for economical and safety reasons. Having complex structures, including topographically with different ranges of form error and roughness, the inspection of asphalt pavement surfaces is difficult to perform non-invasively. In this communication we will report on the optical non-contact rugometric characterization of the surface of different types of road pavements performed at the Microtopography Laboratory of the Physics Department of the University of Minho.

  1. Interim revision of the South African Mechanistic-Empirical pavement design method for flexible pavements

    CSIR Research Space (South Africa)

    Theyse, HL

    2011-09-01

    Full Text Available an interim revision of the SAMDM recommending increased contact stress values at the tyre-pavement interface; updated unbound material characterisation parameters; effective stress analysis for unbound material; and revised damage models for estimating...

  2. Mechanistic-Empirical Pavement Design Guide Flexible Pavement Performance Prediction Models Volume I Executive Research Summary

    Science.gov (United States)

    2007-08-01

    The objective of this research study was to develop performance characteristics or variables (e.g., ride quality, rutting, : fatigue cracking, transverse cracking) of flexible pavements in Montana, and to use these characteristics in the : implementa...

  3. Mechanistic-Empirical Pavement Design Guide Flexible Pavement Performance Prediction Models Volume II Reference Manual

    Science.gov (United States)

    2007-08-01

    The objective of this research study was to develop performance characteristics or variables (e.g., ride quality, rutting, : fatigue cracking, transverse cracking) of flexible pavements in Montana, and to use these characteristics in the : implementa...

  4. Tyre-pavement interface contact stresses on flexible pavements - quo vadis?

    CSIR Research Space (South Africa)

    De Beer, Morris

    2004-09-01

    Full Text Available on tyre inflation pressure on this route is also given. The paper also discusses an improved definition of the actual tyre/pavement interaction of modern heavy vehicles and their loads on the current flexible road infrastructure....

  5. Development of Pavement Condition Index Model Using PAVER 6.5.7 for Flexible Pavement Urban Roads in Kerbala City

    Directory of Open Access Journals (Sweden)

    Hussein Ali Ewadh

    2017-08-01

    Full Text Available The pavement condition index (PCI is an important factor indicating pavement condition of roads. The pavement is one of the basic parts of the road infrastructure. Accordingly the aim of this paper is to develop a pavement condition index model using PAVER 6.5.7 for a flexible pavement urban roads in the Kerbala city center. The development model is depending on the PCI value of 109 sample sections having 57.8 km length, Data collected for pavement distress (type, dimension, and severity were used to find PCI. The filtering and outlier analysis was done by using a polynomial (fourth-degree constrained least squared for statistical process. These processes were done by (PAVER 6.5.7 software. The result of the prediction model of PCI shows that it is valid to be used in the prediction of the condition of pavement for the same family type

  6. Lower Gastrointestinal Bleeding in Children.

    Science.gov (United States)

    Sahn, Benjamin; Bitton, Samuel

    2016-01-01

    This article provides an overview of the evaluation and management of lower gastrointestinal bleeding (LGIB) in children. The common etiologies at different ages are reviewed. Conditions with endoscopic importance for diagnosis or therapy include solitary rectal ulcer syndrome, polyps, vascular lesions, and colonic inflammation and ulceration. Diagnostic modalities for identifying causes of LGIB in children include endoscopy and colonoscopy, cross-sectional and nuclear medicine imaging, video capsule endoscopy, and enteroscopy. Pre-endoscopic preparation and decision-making unique to pediatrics is highlighted. The authors conclude with a summary of current and emerging therapeutic hemostatic techniques that can be used in pediatric patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Integration of pavement cracking prediction model with asset management and vehicle-infrastructure interaction models.

    Science.gov (United States)

    2015-01-01

    Not long after the construction of a pavement or a new pavement surface, various : forms of deterioration begin to accumulate due to the harsh effects of traffic loading : combined with weathering action. In a recent NEXTRANS project, a pavement crac...

  8. Multi-resolution information mining and a computer vision approach to pavement condition distress analysis.

    Science.gov (United States)

    2014-07-01

    Pavement Condition surveys are carried out periodically to gather information on pavement distresses that will guide decision-making for maintenance and preservation. Traditional methods involve manual pavement inspections which are time-consuming : ...

  9. Evaluation of Long-Life Concrete Pavement Practices for Use in Florida : [Summary

    Science.gov (United States)

    2012-01-01

    Current Florida construction practices produce asphalt pavements with a service life of 12 to 20 years before needing rehabilitation; concrete pavements are typically designed for 20 years. However, pavements with much longer design lives are possibl...

  10. Evaluation of Long-Life Concrete Pavement Practices for Use in Florida

    Science.gov (United States)

    2012-11-01

    Current Florida construction practices produce asphalt pavements with a service life of 12 to 20 years before needing rehabilitation; concrete pavements are typically designed for 20 years. However, pavements with much longer design lives are possibl...

  11. Determination of coefficient of thermal expansion effects on Louisiana's PCC pavement design.

    Science.gov (United States)

    2011-12-01

    With the development of the Mechanistic Empirical Pavement Design Guide (MEPDG) as a new pavement design tool, the : coefficient of thermal expansion (CTE) is now considered a more important design parameter in estimating pavement : performance inclu...

  12. Determination of coefficient of thermal expansion for Portland Cement Concrete pavements for MEPDG Implementation

    Science.gov (United States)

    2012-10-01

    The Coefficient of Thermal Expansion (CTE) is an important parameter in Portland Cement Concrete (PCC) pavement analysis and design as it is directly proportional to the magnitude of temperature-related pavement deformations throughout the pavement s...

  13. Measurement, Construction, and Maintenance of Skid-Resistant Airport Pavement Surfaces

    Science.gov (United States)

    1997-03-18

    This advisory circular (AC) contains guidelines and procedures for the design : and construction of skid-resistant pavement, pavement evaluation with friction : measuring equipment, and maintenance of high skid-resistant pavements. 45p.

  14. On-board sound intensity tire-pavement noise study in North Carolina.

    Science.gov (United States)

    2011-12-01

    "This research investigated tire-pavement noise on various types of pavements across North Carolina by using On- : Board Sound Intensity (OBSI) method. To mitigate traffic noise, quieter pavement may provide advantages that : noise barriers cannot. T...

  15. Developing a network-level structural capacity index for structural evaluation of pavements.

    Science.gov (United States)

    2013-03-01

    The objective of this project was to develop a structural index for use in network-level pavement evaluation to facilitate : the inclusion of the pavements structural condition in pavement management applications. The primary goal of network-level...

  16. Predicting pavement condition index using international roughness index in Washington DC.

    Science.gov (United States)

    2014-09-01

    A number of pavement condition indices are used to conduct pavement management assessments, two of which are the : International Roughness Index (IRI) and Pavement Condition Index (PCI). The IRI is typically measured using specialized : equipment tha...

  17. Cracking of open traffic rigid pavement

    Directory of Open Access Journals (Sweden)

    Niken Chatarina

    2017-01-01

    Full Text Available The research is done by observing the growth of real structure cracking in Natar, Lampung, Indonesia compared to C. Niken’s et al research and literature study. The rigid pavement was done with open traffic system. There are two main crack types on Natar rigid pavement: cracks cross the road, and cracks spreads on rigid pavement surface. The observation of cracks was analyzed by analyzing material, casting, curing, loading and shrinkage mechanism. The relationship between these analysis and shrinkage mechanism was studied in concrete micro structure. Open traffic make hydration process occur under vibration; therefore, fresh concrete was compressed and tensioned alternately since beginning. High temperature together with compression, cement dissociation, the growth of Ca2+ at very early age leads abnormal swelling. No prevention from outside water movement leads hydration process occur with limited water which caused spreads fine cracks. Limited water improves shrinkage and plastic phase becomes shorter; therefore, rigid pavement can’t accommodate the abnormal swelling and shrinking alternately and creates the spread of cracks. Discontinuing casting the concrete makes both mix under different condition, the first is shrink and the second is swell and creates weak line on the border; so, the cracks appear as cracks across the road.

  18. Permeable pavement research – Edison, New Jersey

    Science.gov (United States)

    These are the slides for the New York City Concrete Promotional Council Pervious Concrete Seminar presentation. The basis for the project, the monitoring design and some preliminary monitoring data from the permeable pavement parking lot at the Edison Environmental Center are pre...

  19. Development of New Bituminous Pavement Design Method

    DEFF Research Database (Denmark)

    Ullidtz, Per

    The report and work of COST Action 333 sets in place the foundation for a coherent, cost-effective and harmonised European pavement design method. In order to do this, the work programme focused on information gathering, identification of requirements and the selection of the necessary design...

  20. "Full-Scale Testing of Pavement Response"

    DEFF Research Database (Denmark)

    Ullidtz, Per; Ekdahl, Peter

    1998-01-01

    methods for determining stresses, strains and deflections in pavement structurers.Falling Weight Deflectometer (FWD) test were done on the test sections, and stresses and strains were measured both under FWD loading and under a rolling wheel load. Different back-analysis procedures were used to derive...

  1. Microstructural pavement material characterization: some examples

    CSIR Research Space (South Africa)

    Mgangira, Martin B

    2008-07-01

    Full Text Available The utilisation of advanced measurement techniques should assist in the characterization of pavement materials at a micro-scale. The motivating factor for such an approach is that material properties at the micro-level have a critical role...

  2. Texas perpetual pavements : new design guidelines.

    Science.gov (United States)

    2010-06-01

    Since 2001, the State of Texas has been designing and constructing perpetual pavements : on some of its heavily trafficked highways where the expected 20-year truck-traffic estimate of : 18 kip ESALs is in excess of 30 million (TxDOT, 2001). To date,...

  3. Relationship between road pavement failures, engineering indices ...

    African Journals Online (AJOL)

    This article presents the results of a study carried out to relate the frequency of pavement failures, the engineering indices of the subgrade materials and the underlying geology. The results show a high variability in the indices such as the liquid limit, LL, the plasticity index, PI, the maximum dry density, MDD, the optimum ...

  4. The Reflective Cracking in Flexible Pavements

    Directory of Open Access Journals (Sweden)

    Pais Jorge

    2013-07-01

    Full Text Available Reflective cracking is a major concern for engineers facing the problem of road maintenance and rehabilitation. The problem appears due to the presence of cracks in the old pavement layers that propagate into the pavement overlay layer when traffic load passes over the cracks and due to the temperature variation. The stress concentration in the overlay just above the existing cracks is responsible for the appearance and crack propagation throughout the overlay. The analysis of the reflective cracking phenomenon is usually made by numerical modeling simulating the presence of cracks in the existing pavement and the stress concentration in the crack tip is assessed to predict either the cracking propagation rate or the expected fatigue life of the overlay. Numerical modeling to study reflective cracking is made by simulating one crack in the existing pavement and the loading is usually applied considering the shear mode of crack opening. Sometimes the simulation considers the mode I of crack opening, mainly when temperature effects are predominant.

  5. Pavement behaviour under the super single tyre

    CSIR Research Space (South Africa)

    Viljoen, AW

    1982-06-01

    Full Text Available Pavement behaviour under the super single tyre (SST) was investigated and compared with that under a conventional dual tyre (CDT). Contact areas and contact pressures over a range of loading conditions were measured and compared. Two approaches were...

  6. Lessons learned : pavement marking warranty contract.

    Science.gov (United States)

    2013-12-01

    In 2012, UDOT implemented a performance-based warranty on a portion of an I-15 pavement marking : project. The awarded contract requested a contractor warranty on the implemented markings for a total : duration of six years. This is the first time th...

  7. [APPROACH TO PATIENTS WITH GASTROINTESTINAL BLEEDING].

    Science.gov (United States)

    Nikolić, M; Hanževački, M; Jurčić, P; Budimir, I; Ljubičić, N

    2015-11-01

    In the developed Western countries, despite the accumulation of knowledge about the causes and treatment of gastrointestinal bleeding, as well as the experience of gastroenterologists-endoscopists using sophisticated endoscopic devices, the number of hospitalizations and mortality rates has not declined as expected. The most likely explanations are the following: aging population, increased prevalence of alcoholic liver cirrhosis, gastroesophageal reflux disease and obesity, Helicobacter pylori antibiotic resistance, using dual anti-aggregation therapy, anticoagulants, and excessive use of nonsteroidal anti-inflammatory drugs. The aim of this paper is to show the incidence and the most common signs and symptoms of gastrointestinal bleeding. The aim is also to present initial clinical evaluation, diagnostic methods, the main causes of gastrointestinal bleeding, endoscopic hemostatic modalities and treatment of bleeding from the upper and lower gastrointestinal tract. Using the MEDLINE and Ovid databases, we searched the meta-analyses and systematic reviews published in English during the 2005-2015 period. Meta-analyses included results of randomized, double-blind studies on adults treated for gastrointestinal bleeding. Included were guidelines of the European and American Society of Gastroenterological Endoscopy, as well as recent expert work. In this review, we bring the state-of-the-art on gastrointestinal bleeding, new classification of gastrointestinal bleeding from the upper, mid and lower gut, controversy of nasogastric tube placement, use of prokinetic agents and inhibitor proton pumps in acute gastrointestinal bleeding from the upper tract, restrictive transfusion strategy, useful clinical stratification of the severity of bleeding, indications for hospitalization and outcome of using the clinical bleeding score, proper use of gastroprotection in patients at a high risk of peptic ulcer, the need of initial endoscopy, variceal assessment in newly diagnosed

  8. Management of bleeding gastroduodenal ulcers

    DEFF Research Database (Denmark)

    Laursen, Stig Borbjerg; Jørgensen, Henrik Stig; Schaffalitzky de Muckadell, Ove B

    2012-01-01

    Description: A multidisciplinary group of Danish experts developed this guideline on management of bleeding gastroduodenal ulcers. Sources of data included published studies up to March 2011. Quality of evidence and strength of recommendations have been graded. The guideline was approved by the D......Description: A multidisciplinary group of Danish experts developed this guideline on management of bleeding gastroduodenal ulcers. Sources of data included published studies up to March 2011. Quality of evidence and strength of recommendations have been graded. The guideline was approved...... by the Danish Society of Gastroenterology and Hepatology September 4, 2011. Recommendations: Recommendations emphasize the importance of early and efficient resuscitation. Endoscopy should generally be performed within 24 hours, reducing operation rate, rebleeding rate and duration of in-patient stay. When...... in achieving endoscopic hemostasis. Use of endoscopic monotherapy with epinephrine injection is not recommended. Intravenous high-dose proton pump inhibitor (PPI) therapy for 72 hours after successful endoscopic hemostasis is recommended as it decreases both rebleeding rate and mortality in patients with high...

  9. Gastric ulcer bleeding: diagnosis by computed tomography

    International Nuclear Information System (INIS)

    Voloudaki, Argyro; Tsagaraki, Kaliopi; Mouzas, John; Gourtsoyiannis, Nickolas

    1999-01-01

    A case of CT demonstration of a bleeding gastric ulcer is presented, in a patient with confusing clinical manifestations. Abdominal CT was performed without oral contrast medium administration, and showed extravasation of intravenous contrast into a gastric lumen distended with material of mixed attenuation. It is postulated that if radiopaque oral contrast had been given, peptic ulcer bleeding would probably have been masked. CT demonstration of gastric ulcer bleeding, may be of value in cases of differential diagnostic dilemmas

  10. Digital image processing as a tool for pavement distress evaluation

    Science.gov (United States)

    Georgopoulos, A.; Loizos, A.; Flouda, A.

    The information obtained through accurate condition assessment of pavement surface distress data is needed as an essential input to any decision making process concerning pavement management policy. At the same time technological advances in automated inspection systems provide the opportunity to automate the collection and evaluation of the pavement surface condition. In this paper a method developed jointly by the Laboratories of Highway Engineering and Photogrammetry of the National Technical University of Athens is described and proposed. The method involves digital image processing techniques to provide suitable digital imagery as input to specialised software developed especially for this project. This software determines objectively and fully automatically the type, the extent and the severity of surface crackings for flexible road pavements. The proposed method presenten substantial agreement, when compared with systematic visual ratings of existing pavement crackings carried out according to the internationally accepted requirements for airfield and road pavement of the Federal Aviation Administration (FAA).

  11. Management of acute gastric varices bleeding

    Directory of Open Access Journals (Sweden)

    Chen-Jung Chang

    2013-10-01

    Full Text Available Gastroesophageal varices bleeding is a major complication in patients with cirrhosis. Gastric varices (GVs occur in approximately 20% of patients with portal hypertension. However, GV bleeding develops in only 25% of patients with GV and requires more transfusion and has higher mortality than esophageal variceal (EV bleeding. The best strategy for managing acute GV bleeding is similar to that of acute EV bleeding, which involves airway protection, hemodynamic stabilization, and intensive care. Blood transfusion should be cautiously administered in order to avoid rebleeding. Vasoactive agents such as terlipressin or somatostatin should be used when GV bleeding is suspected. Routine use of prophylactic antibiotics reduces bacterial infection and lowers rebleeding rates. By administering endoscopic cyanoacrylate injection, the initial hemostasis rate achieved is at least 90% in most cases; the average mortality rate of GV bleeding is approximately 10–30% and the rebleeding rate is between 22% and 37%. Although endoscopic injection of cyanoacrylate is superior to sclerotherapy and band ligation, and has remained the treatment of choice for treating acute GV bleeding, the outcome of this treatment is still unsatisfactory. New treatment options, such as thrombin injection, transjugular intrahepatic portosystemic shunts, or balloon-occluded retrograde transvenous obliteration, have shown promising results for acute GV bleeding. However, randomized controlled trials are needed to compare the efficacy of these therapies with cyanoacrylate.

  12. [Gastrointestinal bleeding, NSAIDs, aspirin and anticoagulants].

    Science.gov (United States)

    Lanas, Ángel

    2014-09-01

    The studies presented at the recent American Congress of Gastroenterology in the field of non-variceal upper gastrointestinal bleeding (associated or not to NSAIDs or ASA use) have not been numerous but interesting. The key findings are: a) rabeprazole, the only PPI that had few studies in this field, is effective in the prevention of gastric ulcers; b) famotidine could also be effective in the prevention of complications by AAS; c) the new competitive inhibitors of the acid potassium pump are effective (as much as PPIs) on the recurrence of peptic ulcers by ASA; d) early endoscop (<8 h) in non-variceal upper gastrointestinal bleeding seems to offer no better results than those made in the first 24 h; e) endoscopic therapy in Forrest 1a ulcers does not obliterate the bleeding artery in 30% of cases and is the cause of bleeding recurrence; f) alternative therapies with glue or clotting products are being increasingly used in endoscopic therapy of gastrointestinal bleeding; g) liberal administration of blood in the GI bleeding is associated with poor prognosis; h) lesions of the small intestine are frequent cause of gastrointestinal bleeding when upper endoscopy shows no positive stigmata; and i) capsule endoscopy studies have high performance in gastrointestinal bleeding of obscure origin, if performed early in the first two days after the beginning of the bleeding episode. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  13. Serendipity in scintigraphic gastrointestinal bleeding studies

    International Nuclear Information System (INIS)

    Goergen, T.G.

    1983-01-01

    A retrospective review of 80 scintigraphic bleeding studies performed with Tc-99m sulfur colloid or Tc-99m labeled red blood cells showed five cases where there were abnormal findings not related to bleeding. In some cases, the abnormalities were initially confused with bleeding or could obscure an area of bleeding, while in other cases, the abnormalities represented additional clinical information. These included bone marrow replacement related to tumor and radiation therapy, hyperemia related to a uterine leiomyoma and a diverticular abscess, and a dilated abdominal aorta (aneurysm). Recognition of such abnormalities should prevent an erroneous diagnosis and the additional information may be of clinical value

  14. Serendipity in scintigraphic gastrointestinal bleeding studies

    Energy Technology Data Exchange (ETDEWEB)

    Goergen, T.G.

    1983-09-01

    A retrospective review of 80 scintigraphic bleeding studies performed with Tc-99m sulfur colloid or Tc-99m labeled red blood cells showed five cases where there were abnormal findings not related to bleeding. In some cases, the abnormalities were initially confused with bleeding or could obscure an area of bleeding, while in other cases, the abnormalities represented additional clinical information. These included bone marrow replacement related to tumor and radiation therapy, hyperemia related to a uterine leiomyoma and a diverticular abscess, and a dilated abdominal aorta (aneurysm). Recognition of such abnormalities should prevent an erroneous diagnosis and the additional information may be of clinical value.

  15. COMPARISON OF LIFE CYCLE ASSESSMENT TOOLS FOR ROAD PAVEMENT INFRASTRUCTURE

    OpenAIRE

    OLIVEIRA DOS SANTOS , Joao Miguel; THYAGARAJAN , Senthilmurugan; KEIJZER , Elisabeth; FERNANDEZ FLORES , Rocio; FLINTSCH , Gerardo

    2017-01-01

    Road pavements have considerable environmental burdens associated with their initial construction, maintenance, and usage, which has led the pavement stakeholder community to congregate efforts to better understand and mitigate these negative effects. Life cycle assessment (LCA) is a versatile methodology to quantify the effect of decisions regarding the selection of resources and processes. However, there is a considerable variety of tools for conducting pavement LCA. The objective of this p...

  16. Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash

    OpenAIRE

    Yoshitake, Isamu; Ishida, Takeo; Fukumoto, Sunao

    2015-01-01

    Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone pow...

  17. Incorporating moving dynamic tyre loads in pavement design and analysis

    CSIR Research Space (South Africa)

    Steyn, WJvdM

    2000-07-01

    Full Text Available at the University of Pretoria. 4 REAL LIFE TYRE LOADS Characterisation Pavement loading has been shown by various authors to be a dynamic (time-dependent) phenomenon (Divine, 1997; Cebon, 1999). A pavement experiences a vehicle as a moving, time-varying set... is that caused by the pavement roughness-induced movement of the vehicle. This is traditionally termed dynamic pavement loading (Divine, 1997). Tyre load definitions Four types of tyre loading can be identified: 1. A load that is independent of time...

  18. Environmentally friendly pavements: Results from noise measurements 2005-2008

    OpenAIRE

    Berge, Truls Svenn; Haukland, Frode; Ustad, Asbjørn

    2009-01-01

    CPX-measurements (tyre A) have been performed on a wide range of ordinary dense Norwegian road pavements and special test pavements, as part of the R&D project “Environmental friendly pavements” initiated by the Norwegian Public Roads Administration. The following conclusions can be made from the investigation:- New dense asphalt concrete pavements can give a tyre/road noise level (CPX) of 4-8 dB(A) lower noise level, compared to a chosen reference level for a pavement of type AC 0/1...

  19. Study on Flexible Pavement Failures in Soft Soil Tropical Regions

    Science.gov (United States)

    Jayakumar, M.; Chee Soon, Lee

    2015-04-01

    Road network system experienced rapid upgrowth since ages ago and it started developing in Malaysia during the colonization of British due to its significant impacts in transportation field. Flexible pavement, the major road network in Malaysia, has been deteriorating by various types of distresses which cause descending serviceability of the pavement structure. This paper discusses the pavement condition assessment carried out in Sarawak and Sabah, Malaysia to have design solutions for flexible pavement failures. Field tests were conducted to examine the subgrade strength of existing roads in Sarawak at various failure locations, to assess the impact of subgrade strength on pavement failures. Research outcomes from field condition assessment and subgrade testing showed that the critical causes of pavement failures are inadequate design and maintenance of drainage system and shoulder cross fall, along with inadequate pavement thickness provided by may be assuming the conservative value of soil strength at optimum moisture content, whereas the exiting and expected subgrade strengths at equilibrium moisture content are far below. Our further research shows that stabilized existing recycled asphalt and base materials to use as a sub-base along with bitumen stabilized open graded base in the pavement composition may be a viable solution for pavement failures.

  20. Crack identification for rigid pavements using unmanned aerial vehicles

    Science.gov (United States)

    Bahaddin Ersoz, Ahmet; Pekcan, Onur; Teke, Turker

    2017-09-01

    Pavement condition assessment is an essential piece of modern pavement management systems as rehabilitation strategies are planned based upon its outcomes. For proper evaluation of existing pavements, they must be continuously and effectively monitored using practical means. Conventionally, truck-based pavement monitoring systems have been in-use in assessing the remaining life of in-service pavements. Although such systems produce accurate results, their use can be expensive and data processing can be time consuming, which make them infeasible considering the demand for quick pavement evaluation. To overcome such problems, Unmanned Aerial Vehicles (UAVs) can be used as an alternative as they are relatively cheaper and easier-to-use. In this study, we propose a UAV based pavement crack identification system for monitoring rigid pavements’ existing conditions. The system consists of recently introduced image processing algorithms used together with conventional machine learning techniques, both of which are used to perform detection of cracks on rigid pavements’ surface and their classification. Through image processing, the distinct features of labelled crack bodies are first obtained from the UAV based images and then used for training of a Support Vector Machine (SVM) model. The performance of the developed SVM model was assessed with a field study performed along a rigid pavement exposed to low traffic and serious temperature changes. Available cracks were classified using the UAV based system and obtained results indicate it ensures a good alternative solution for pavement monitoring applications.

  1. Performance of recycled asphalt concrete airport pavement surfaces

    Science.gov (United States)

    Cline, G. D.; Hironaka, M. C.

    1986-10-01

    The objective of this research was to make an assessment of the relative performance of recycled versus new asphalt concrete pavement surfaces constructed for airport facilities. To make this assessment, pavement condition index (PCI) surveys and tests on core samples from the hot-mix recycled pavements located on the airports at Needles, California, and Valley City, North Dakota were conducted. Both pavements have a condition rating of very good. The survey and test data were compared with those for recycled highway and virgin material Navy airfield pavements. The recycle pavement at Needles is performing as good as those Navy pavements constructed with virgin material. The recycled pavement at Valley City has a higher deterioration rate than the Navy pavements but this could be attributed to the harsh climate found in North Dakota. The results of this study show that hot-mix recycling was successful at these airports but additional studies are required to determine the applicability of Asphalt Concrete (AC) recycling for reconstruction at all airports.

  2. Identification of Pavement Distress Types and Pavement Condition Evaluation Based on Network Level Inspection for Jazan City Road Network

    OpenAIRE

    M Mubaraki

    2014-01-01

    The first step in establishing a pavement management system (PMS) is road network identification. An important feature of a PMS is the ability to determine the current condition of a road network and predict its future condition. Pavement condition evaluation may involve structure, roughness, surface distress, and safety evaluation. In this study, a pavement distress condition rating procedure was used to achieve the objectives of this study. The main objectives of this study were to identify...

  3. Massive rectal bleeding from colonic diverticulosis | Olokoba ...

    African Journals Online (AJOL)

    Objectives: This is to describe a case of colonic diverticulosis causing massive rectal bleeding in an elderly Nigerian man. Case report: We highlight a case of a 79 year old man who presented with massive rectal bleeding due to colonic diverticulosis from our centre. Colonoscopy identified multiple diverticula in the ...

  4. Gastrointestinal bleeding following NSAID ingestion in children

    African Journals Online (AJOL)

    presented with GI bleeding following ingestion of NSAID. Two female children ... users of NSAIDs [2]. The risk and the magnitude of. NSAID-induced GI injury in children are uncertain. Here, we report two cases of GI bleeding in children following NSAID use. .... Nonsteroidal anti-inflammatory drug induced gastrointestinal ...

  5. Rectal bleeding in children: endoscopic evaluation revisited

    NARCIS (Netherlands)

    de Ridder, Lissy; van Lingen, Anna V.; Taminiau, Jan A. J. M.; Benninga, Marc A.

    2007-01-01

    Objectives Rectal bleeding is an alarming event both for the child and parents. It is hypothesized that colonoscopy instead of sigmoidoscopy and adding esophago-gastro-duodenoscopy in case of accompanying complaints, improves the diagnostic accuracy in children with prolonged rectal bleeding. Study

  6. RESEARCH Endoscopic injection sclerotherapy for bleeding varices ...

    African Journals Online (AJOL)

    Portal hypertension due to intrahepatic disease or extrahepatic portal vein obstruction (EHPVO) is an important cause of upper gastro- intestinal bleeding in children. About 50% of children with EHPVO present with bleeding from oesophageal varices.1-3 Improvements in the management of children with intrahepatic ...

  7. Duodenal diverticular bleeding: an endoscopic challenge

    Directory of Open Access Journals (Sweden)

    Eduardo Valdivielso-Cortázar

    Full Text Available Duodenal diverticula are an uncommon cause of upper gastrointestinal bleeding. Until recently, it was primarily managed with surgery, but advances in the field of endoscopy have made management increasingly less invasive. We report a case of duodenal diverticular bleeding that was endoscopically managed, and review the literature about the various endoscopic therapies thus far described.

  8. Dysfunctional Uterine Bleeding (DUB) (For Teens)

    Science.gov (United States)

    ... Feelings Expert Answers Q&A Movies & More for Teens Teens site Sitio para adolescentes Body Mind Sexual Health ... English Español Abnormal Uterine Bleeding (AUB) KidsHealth / For Teens / Abnormal Uterine Bleeding (AUB) What's in this article? ...

  9. Massive rectal bleeding from colonic diverticulosis

    African Journals Online (AJOL)

    ABEOLUGBENGAS

    Objectives: This is to describe a case of colonic diverticulosis causing massive rectal bleeding in an elderly Nigerian man. ... also oozing blood. He was worked up, and had surgery for hemicolectomy due to massive blood loss following failure of initial conservative management. .... bleeding patterns observed in fifty cases.

  10. Microorganism Removal in Permeable Pavement Parking Lots ...

    Science.gov (United States)

    Three types of permeable pavements (pervious concrete, permeable interlocking concrete pavers, and porous asphalt) were monitored at the Edison Environmental Center in Edison, New Jersey for indicator organisms such as fecal coliform, enterococci, and E. coli. Results showed that porous asphalt had much lower concentration in monitored infiltrate compared to pervious concrete and permeable interlocking concrete pavers. Concentrations of monitored organisms in infiltrate from porous asphalt were consistently below the bathing water quality standard. Fecal coliform and enterococci exceeded bathing water quality standards more than 72% and 34% of the time for permeable interlocking concrete pavers and pervious concrete, respectively. Purpose is to evaluate the performance of permeable pavement in removing indicator organisms from infiltrating stormwater runoff.

  11. Transarterial embolization of acute intercostal artery bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Jae Ik; Park, Auh Whan; Lee, Seon Joo [Inje University College of Medicine, Busan (Korea, Republic of); Ko, Gi Young; Yoon, Hyun Ki [University of Ulsan College of Medicine, Seoul (Korea, Republic of); Yoon, Chang Jin [Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Shin, Tae Beom [Donga University College of Medicine, Busan (Korea, Republic of); Kim, Young Hwan [Kyimyung University School of Medicine, Daegu (Korea, Republic of)

    2005-09-15

    To report our experiences of transarterial embolization for acute intercostal artery bleeding. A retrospectively analysis of the causes, clinical manifestations, angiographic findings and transarterial embolization technique in 8 patients with acute intercostal artery bleeding, with a review of the anatomical basis. The causes of intercostal artery bleeding were iatrogenic and traumatic in 88 and 12% of cases, respectively. Active bleeding from the collateral intercostal or posterior intercostal arteries was angiographically demonstrated in 75 and 25% of cases, respectively. Transarterial embolization successfully achieved hemostasis in all cases. However, two patient with hypovolemic shock expired due to a massive hemothorax, despite successful transarterial embolization. Intercostal access should be performed through the middle of the intercostal space to avoid injury to the collateral intercostal artery. Transarterial embolization is an effective method for the control of intercostal artery bleeding.

  12. Applications of observational techniques in pavement engineering

    CSIR Research Space (South Africa)

    Steyn, WJVDM

    2007-05-01

    Full Text Available used to obtain these images. Higher resolution images are available through the Agricultural Research Council (ARC) AGIS (Agricultural Geo-Referenced Information System) site. This site provides detailed information on soil, terrain, geology, climate... pavement to be either under- or over-estimated. A further aspect that requires attention during the process of obtaining the images for observational analysis is to ensure that all images are clearly identifiable through a system that would lead...

  13. Pavement cells and the topology puzzle.

    Science.gov (United States)

    Carter, Ross; Sánchez-Corrales, Yara E; Hartley, Matthew; Grieneisen, Verônica A; Marée, Athanasius F M

    2017-12-01

    D'Arcy Thompson emphasised the importance of surface tension as a potential driving force in establishing cell shape and topology within tissues. Leaf epidermal pavement cells grow into jigsaw-piece shapes, highly deviating from such classical forms. We investigate the topology of developing Arabidopsis leaves composed solely of pavement cells. Image analysis of around 50,000 cells reveals a clear and unique topological signature, deviating from previously studied epidermal tissues. This topological distribution is established early during leaf development, already before the typical pavement cell shapes emerge, with topological homeostasis maintained throughout growth and unaltered between division and maturation zones. Simulating graph models, we identify a heuristic cellular division rule that reproduces the observed topology. Our parsimonious model predicts how and when cells effectively place their division plane with respect to their neighbours. We verify the predicted dynamics through in vivo tracking of 800 mitotic events, and conclude that the distinct topology is not a direct consequence of the jigsaw piece-like shape of the cells, but rather owes itself to a strongly life history-driven process, with limited impact from cell-surface mechanics. © 2017. Published by The Company of Biologists Ltd.

  14. Microtexture diagnostics of asphalt pavement surfaces

    Science.gov (United States)

    Florková, Zuzana; Pepucha, L.'ubomír

    2017-09-01

    The microtexture of asphalt pavement surface is an essential parameter from the traffic safety point of view and it closely relates to a geometrical, petrological and physical properties of aggregate particle used in asphalt pavement. Microtexture has a significant influence for assurance basic friction values between tire and pavement in relation to a skid resistance properties. Therefore, the microtexture detecting methods are necessary. The British pendulum tester measurements have been carried out on selected sections of roads with different asphalt surfaces. Individual grains of aggregates were taken from the surface of each section from the sliding path and also from the core sample after the extraction. The laboratory profilometry measurements have been practiced on these aggregate samples and subsequently the surface microtexture was investigated based on commonly used texture characteristics and the filtration approach was applied in calculation process. The results have shown the degradation of microtexture values occurs due to polishing of aggregate under loading from traffic in relation to the type of used aggregate. Some correlation between BPN values and texture characteristics was found.

  15. Portland cement concrete pavement best practices summary report.

    Science.gov (United States)

    2010-08-01

    This report summarizes the work and findings from WA-RD 744. This work consisted of four separate efforts related to best practices for portland cement concrete (PCC) pavement design and construction: (1) a review of past and current PCC pavement, (2...

  16. Soil Properties And Pavement Performance In The Nigerian Rainforest

    African Journals Online (AJOL)

    The geotechnical properties of the sub-structure of the Shagamu-Ore-Benin pavement were studied in an attempt to identifying the quality of construction materials and the pavement performance. The sub-structure soil materials were collected from the field and were taken to the laboratory for particle size analysis, Atterberg ...

  17. Inclusion of LCCA in Alaska flexible pavement design software manual.

    Science.gov (United States)

    2012-10-01

    Life cycle cost analysis is a key part for selecting materials and techniques that optimize the service life of a pavement in terms of cost and performance. While the Alaska : Flexible Pavement Design software has been in use since 2004, there is no ...

  18. Estimating the benefits of improved drainage on pavement ...

    African Journals Online (AJOL)

    user

    The drainage quality is an important parameter which affects the performance of highway pavements. In India ... pavement performance and maintenance needs; and (iii) to quantify the benefits in terms of cost due to the improved drainage ...... Jain was the founder Head of Excellence in Transportation Systems (CTRANS),.

  19. Soil Properties And Pavement Performance In The Nigerian ...

    African Journals Online (AJOL)

    The geotechnical properties of the sub-structure of the Shagamu-Ore-Benin pavement were studied in an attempt to identifying the quality of construction materials and the pavement performance. The sub-structure soil materials were collected from the field and were taken to the laboratory for particle size analysis, Atterberg ...

  20. Long-term Metal Performance of Three Permeable Pavements

    Science.gov (United States)

    EPA constructed a 4,000-m2 parking lot surfaced with three permeable pavements (permeable interlocking concrete pavers, pervious concrete, and porous asphalt) on the Edison Environmental Center in Edison, NJ in 2009. Samples from each permeable pavement infiltrate were collected...

  1. Engineering properties of common subgrade soils below pavement ...

    African Journals Online (AJOL)

    This paper reports findings of laboratory testing of common sub-grade soils in pavement structures in Kenya. The materials were collected from different parts of the country. The results are intended to form a database for use by practicing engineers and researchers in the field of pavement engineering. The investigated ...

  2. Innovations in concrete pavements for a sustainable infrastructure

    NARCIS (Netherlands)

    Pradena, M.; Houben, L.J.M.

    2014-01-01

    Concrete pavements (CPs) are durable and they do not need periodic invasive maintenance interventions. Nevertheless, CPs are hardly chosen when only initial costs, instead of life-cycle costs, are considered in the evaluation. Nowadays, there are innovations in Jointed Plain Concrete Pavements

  3. I-81 in-place pavement recycling project.

    Science.gov (United States)

    2014-08-01

    During the 2011 construction season, the Virginia Department of Transportation (VDOT) completed an in-place pavement : recycling project to rehabilitate a section of pavement on I-81 near Staunton, Virginia. The project consisted of a 3.66-mile : sec...

  4. Initial investigation into development of accelerated pavement evaluation (APE) vehicle

    CSIR Research Space (South Africa)

    Steyn, WJvdM

    2002-08-01

    Full Text Available . This is the option of using the HVS to proof-test a newly constructed or in-service pavement or even to only evaluate the pavement response qualitatively over a very short period. The problem addressed in this report is investigate the opportunity to develop a method...

  5. 3D Tyre/Road pavement contact stress measurements

    CSIR Research Space (South Africa)

    De Beer, Morris

    2010-10-01

    Full Text Available The CSIR’s proprietary Stress-in-Motion (SIM) measurements provide rational descriptions of 1D, 2D and 3D tyre/road pavement stresses for: Road pavement design testing and evaluation, as well as tyre design, testing and evaluation....

  6. Assessing Asphalt and Concrete Pavement Surface Texture in the Field

    Directory of Open Access Journals (Sweden)

    Saad I. Sarsam

    2016-06-01

    Full Text Available The incorporation of safety characteristics into the traditional pavement structural design or in the functional evaluation of pavement condition has not been established yet. The design has focused on the structural capacity of the roadway so that the pavement can withstand specific level of repetitive loading over the design life. On the other hand, the surface texture condition was neither included in the AASHTO design procedure nor in the present serviceability index measurements. The pavement surface course should provide adequate levels of friction and ride quality and maintain low levels of noise and roughness. Many transportation departments perform routine skid resistant testing, the type of equipment used for testing varies depending on the preference of each transportation department. It was felt that modeling of the surface texture condition using different methods of testing may assist in solving such problem. In this work, Macro texture and Micro texture of asphalt and cement concrete pavement surface have been investigated in the field using four different methods (The Sand Patch Method, Outflow Time Method, British Pendulum Tester and Photogrammetry Technique. Two different grain sizes of sand have been utilized in conducting the Sand Patch while the Micro texture was investigated using the British Pendulum tester method at wet pavement surface conditions. The test results of the four methods were correlated to the skid number. It was concluded that such modeling could provide instant data in the field for pavement condition which may help in pavement maintenance management.

  7. Effects of street tree shade on asphalt concrete pavement performance

    Science.gov (United States)

    E.G. McPherson; J. Muchnick

    2005-01-01

    Forty-eight street segments were paired into 24 high-and low-shade pairs in Modesto, California, U.S. Field data were collected to calculate a Pavement Condition Index (PCI) and Tree Shade Index (TSI) for each segment. Statistical analyses found that greater PCI was associated with greater TSI, indicating that tree shade was partially responsible for reduced pavement...

  8. Highway pavement failure induced by poor soil geotechnical ...

    African Journals Online (AJOL)

    X-ray diffraction studies showed the presence of abundant kaolinite peaks and a subdued goethite peak without any trace of montmorrilonite. The presence of excess fines in the pavement construction materials (soils) contributed to the failure of the highway pavement at this locality. The low CBR value is also a noted cause ...

  9. Endoscopic management of bleeding peptic ulcers

    International Nuclear Information System (INIS)

    Farooqi, J.I.; Farooqi, R.J.

    2001-01-01

    Peptic ulcers account for more than half of the cases of non variceal upper gastrointestinal (GI) bleeding and therefore, are the focus of most of the methods of endoscopic hemostasis. Surgical intervention is now largely reserved for patients in whom endoscopic hemostasis has failed. A variety of endoscopic techniques have been employed to stop bleeding and reduce the risk of rebleeding, with no major differences in outcome between these methods. These include injection therapy, fibrin injection, heater probe, mono polar electrocautery, bipolar electrocautery, lasers and mechanical hemo clipping. The most important factor in determining outcome after gastrointestinal bleeding is rebleeding or persistent bleeding. The endoscopic appearance of an ulcer, however, provides the most useful prognostic information for bleeding. Recurrent bleeding after initial endoscopic hemostasis occurs in 15-20% of patients with a bleeding peptic ulcer. The best approach to these patients remains controversial; the current options are repeat endoscopic therapy with the same or a different technique, emergency surgery or semi elective surgery after repeat endoscopic hemostasis. The combination of epinephrine injection with thermal coagulation may be more effective than epinephrine injection alone. Newer modalities such as fibrin injection or the application of hemo clips appear promising and comparative studies are awaited. (author)

  10. THROMBIN GENERATION AND BLEEDING IN HEMOPHILIA A

    Science.gov (United States)

    Brummel-Ziedins, Kathleen E.; Whelihan, Matthew F.; Gissel, Matthew; Mann, Kenneth G.; Rivard, Georges E.

    2012-01-01

    Introduction Hemophilia A displays phenotypic heterogeneity with respect to clinical severity. Aim To determine if tissue factor (TF)-initiated thrombin generation profiles in whole blood in the presence of corn trypsin inhibitor (CTI) are predictive of bleeding risk in hemophilia A. Methods We studied factor(F) VIII deficient individuals (11 mild, 4 moderate and 12 severe) with a well-characterized five-year bleeding history that included hemarthrosis, soft tissue hematoma and annual FVIII concentrate usage. This clinical information was used to generate a bleeding score. The bleeding scores (range 0–32) were separated into three groups (bleeding score groupings: 0, 0 and ≤9.6, >9.6), with the higher bleeding tendency having a higher score. Whole blood collected by phlebotomy and contact pathway suppressed by 100μg/mL CTI was stimulated to react by the addition of 5pM TF. Reactions were quenched at 20min by inhibitors. Thrombin generation, determined by ELISA for thrombin – antithrombin was evaluated in terms of clot time (CT), maximum level (MaxL) and maximum rate (MaxR) and compared to the bleeding score. Results Data are shown as the mean±SD. MaxL was significantly different (phemophilia A. PMID:19563500

  11. Causes of lower gastrointestinal bleeding on colonoscopy

    International Nuclear Information System (INIS)

    Rehman, A.U.; Gul, R.; Khursheed, L.; Hadayat, R.

    2017-01-01

    Background: Bleeding from anus is usually referred as rectal bleeding but actually rectal bleeding is defined as bleeding from lower colon or rectum, which means bleeding from a place distal to ligament of Treitz. This study was conducted to determine the frequency of different causes of rectal bleeding in patients at Ayub Teaching Hospital, Abbottabad. Methods: One hundred and seventy-five patients with evidence of rectal bleed, without gender discrimination were selected by non-probability convenient sampling from the out-patient department and general medical wards. Patients with suspected upper GI source of bleeding; acute infectious bloody diarrhoea and any coagulopathy were excluded from the study. All patients were subjected to fibre optic colonoscopy after preparation of the gut and findings were recorded. Where necessary, biopsy samples were also taken. Diagnosis was based on colonoscopic findings. Results: A total of 175 patients (92 males and 83 females) with mean age 35.81±9.18 years were part of the study. Colonoscopy showed abnormal findings in 150 (85.7%) patients. The commonest diagnosis was haemorrhoids, which was found in 39 (22.3%) patients. It was followed by inflammatory bowel disease (IBD) in 30 (17.1%) patients, solitary rectal ulcer in 13 (7.4%) patients and polyps in 25 (14.3%) patients. Other less frequent findings were non-specific inflammation and fungating growths in rectum. Conclusion: Haemorrhoids was the leading cause of bleeding per rectum in this study, followed by evidence of IBD while infrequent findings of polyps and diverticuli indicate that these are uncommon in this region. (author)

  12. Application of WIM to pavement design. Effect of WIM accuracy

    Directory of Open Access Journals (Sweden)

    J. Leal Bermejo

    2017-03-01

    Full Text Available Weigh-in-motion (WIM techniques can provide data on vehicle and axle weights when they are travelling at full highway speeds. In this paper, the application of WIM data to the design of road pavements is described and the effect of WIM load data accuracy on the estimate of pavement service life is analysed. Thus, the main factors affecting WIM accuracy are explained, especially those related to vehicle-pavement interaction. Afterwards, a trial that has been conducted to evaluate the effect of WIM load data accuracy on pavement life prediction will be presented. The results obtained show that the errors in axle load measurements can lead to higher errors in pavement life estimates.

  13. Compressor bleed cooling fluid feed system

    Science.gov (United States)

    Donahoo, Eric E; Ross, Christopher W

    2014-11-25

    A compressor bleed cooling fluid feed system for a turbine engine for directing cooling fluids from a compressor to a turbine airfoil cooling system to supply cooling fluids to one or more airfoils of a rotor assembly is disclosed. The compressor bleed cooling fluid feed system may enable cooling fluids to be exhausted from a compressor exhaust plenum through a downstream compressor bleed collection chamber and into the turbine airfoil cooling system. As such, the suction created in the compressor exhaust plenum mitigates boundary layer growth along the inner surface while providing flow of cooling fluids to the turbine airfoils.

  14. Evaluation of current Louisiana flexible pavement structures using PMS data and new mechanistic-empirical pavement design guide.

    Science.gov (United States)

    2012-04-01

    The new Mechanistic-Empirical Pavement Design Guide (MEPDG) developed under the National Cooperative Highway Research Program (NCHRP) Project 1-37A represents a major change as compared to the 1993 AASHTO Pavement Design Guide. The MEPDG provides a r...

  15. Photocatalytic pavement blocks. Air purification by pavement blocks. Final results of the research at BRRC

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    The use of materials can influence to a large extent the environmental impact of traffic and of road infrastructure. Especially in urban areas, where the risk on smog formation during hot summer days is high, the use of photocatalytic pavement blocks can reduce the air pollution significantly. A project on environmental friendly concrete pavement blocks is conducted at the Belgian Road Research Centre. The use of photocatalytic material in the surface of pavement blocks to obtain air purifying materials is investigated. In contact with light, TiO2 as photocatalyst, is able to reduce the NO and NO2 content in the air, caused by the exhaust of traffic. The efficiency is tested on pavement blocks, but the technique can as well be applied on other road elements (e.g. noise reducing walls, linear elements) or as a coating on new materials or existing structures. At the previous TRA conference in Gotenborgh, Sweden, the principle of photocatalysis was presented. In this paper, emphasis will be put on the final results of the 4-year project obtained in laboratory as well as on site at the Leien of Antwerp (10,000 m{sup 2}). The results indicate a durable efficiency towards NOx reduction, which is in favour for the diminishing of the risk on ozone formation. However, the precise translation from the laboratory towards the site is still in question. The results obtained during the project are discussed in this paper.

  16. Reconsideration of tyre-pavement input parameters for the structural design of flexible pavements

    CSIR Research Space (South Africa)

    De Beer, Morris

    2006-08-01

    Full Text Available which have higher inflation pressures and hence higher contact stresses than was previously the case. The aim of this paper is to highlight the variabilities associated with actual measured three-dimensional tyre-pavement contact loading/stress regimes...

  17. Pavement noise research : modeling of quieter pavements in Florida, final report, October 19, 2009.

    Science.gov (United States)

    2009-10-01

    The research on noise created by the tire/pavement interface, while relatively new, has seen considerable interest over the past few years because of the potential benefits and a general desire by the public for quieter highways. The Florida Departme...

  18. Pavement structure mechanics response of flexible on semi-flexible overlay that based on the old cement concrete pavement damage

    Directory of Open Access Journals (Sweden)

    Jiang Ruinan

    2015-01-01

    Full Text Available The old cement pavement damage status directly affect the design of the paving renovation. Based on the state of the old road investigation, combined with the research data at home and abroad, use the control index that average deflection, deflection value and CBR value to determine the reasonable time to overlay. Draw up the typical pavement structure according to the principle of combination of old cement pavement overlay structure design, and calculated that the tensile stress and shear stress in asphalt layer ,semi-flexible layer and the tensile in the old cement pavement adopting BISA3.0 statics finite element analysis model when modulus in the old road was diminishing. Use the computed result to analyses the influence of old road damage condition the influence of pavement structure.

  19. Mechanistic-Empirical Pavement Design Guide Flexible Pavement Performance Prediction Models Volume III Field Guide - Calibration and User's Guide for the Mechanistic-Empirical Pavement Design Guide

    Science.gov (United States)

    2007-08-01

    The objective of this research study was to develop performance characteristics or variables (e.g., ride quality, rutting, : fatigue cracking, transverse cracking) of flexible pavements in Montana, and to use these characteristics in the : implementa...

  20. AL Amyloidosis Complicated by Persistent Oral Bleeding

    Directory of Open Access Journals (Sweden)

    Luiz Antonio Liarte Marconcini

    2015-01-01

    Full Text Available A case of amyloid light chain (AL amyloidosis is presented here with uncontrolled bleeding after a nonsurgical dental procedure, most likely multifactorial in nature, and consequently treated with a multidisciplinary approach.

  1. Gastrointestinal Bleeding: MedlinePlus Health Topic

    Science.gov (United States)

    ... peptic ulcers , tears or inflammation in the esophagus, diverticulosis and diverticulitis , ulcerative colitis and Crohn's disease , colonic ... PubMed (National Library of Medicine) Article: Small intestinal diverticulum with bleeding: Case report and literature review. Article: ...

  2. Fibrinogen concentrate for bleeding - a systematic review

    DEFF Research Database (Denmark)

    Lunde, J; Stensballe, J; Wikkelsø, A

    2014-01-01

    included a control group. Three out of 11 found a reduction in transfusion requirements while mortality was reduced in two and bleeding in one. In the available RCTs, which all have substantial shortcomings, we found a significant reduction in bleeding and transfusions requirements. However, data......Fibrinogen concentrate as part of treatment protocols increasingly draws attention. Fibrinogen substitution in cases of hypofibrinogenaemia has the potential to reduce bleeding, transfusion requirement and subsequently reduce morbidity and mortality. A systematic search for randomised controlled...... determined to be of high risk of bias and none reported a significant effect on mortality. Two RCTs found a significant reduction in bleeding and five RCTs found a significant reduction in transfusion requirements. The 23 non-randomised studies included a total of 2825 patients, but only 11 of 23 studies...

  3. CLSM bleed water reduction test results

    International Nuclear Information System (INIS)

    Langton, C.A.; Rajendran, N.

    1997-01-01

    Previous testing by BSRI/SRTC/Raytheon indicated that the CLSM specified for the Tank 20 closure generates about 6 gallons (23 liters) of bleed water per cubic yard of material (0.76 m3).1 This amount to about 10 percent of the total mixing water. HLWE requested that the CLSM mix be optimized to reduce bleed water while maintaining flow. Elimination of bleed water from the CLSM mix specified for High-Level Waste Tank Closure will result in waste minimization, time savings and cost savings. Over thirty mixes were formulated and evaluated at the on-site Raytheon Test Laboratory. Improved low bleed water CLSM mixes were identified. Results are documented in this report

  4. Identification of Pavement Distress Types and Pavement Condition Evaluation Based on Network Level Inspection for Jazan City Road Network

    Directory of Open Access Journals (Sweden)

    M Mubaraki

    2014-06-01

    Full Text Available The first step in establishing a pavement management system (PMS is road network identification. An important feature of a PMS is the ability to determine the current condition of a road network and predict its future condition. Pavement condition evaluation may involve structure, roughness, surface distress, and safety evaluation. In this study, a pavement distress condition rating procedure was used to achieve the objectives of this study. The main objectives of this study were to identify the common types of distress that exist on the Jazan road network (JRN, either on main roads or secondary roads, and to evaluate the pavement condition based on network level inspection. The study was conducted by collecting pavement distress types from 227 sample units on main roads and 500 sample units from secondary roads. Data were examined through analysis of common types of distress identified in both main and secondary roads. Through these data, pavement condition index (PCI for each sample unit was then calculated. Through these calculations, average PCIs for the main and secondary roads were determined. Results indicated that the most common pavement distress types on main roads were patching and utility cut patching, longitudinal and transverse cracking, polished aggregate, weathering and raveling, and alligator cracking. The most common pavement distress types on secondary roads were weathering and raveling, patching and utility cut patching, longitudinal and transverse cracking, potholes, and alligator cracking. The results also indicated that 65% of Jazan's main road network has an average pavement condition rating of very good while only 30% of Jazan's secondary roads network has an average pavement condition.

  5. Management of patients with ulcer bleeding.

    Science.gov (United States)

    Laine, Loren; Jensen, Dennis M

    2012-03-01

    This guideline presents recommendations for the step-wise management of patients with overt upper gastrointestinal bleeding. Hemodynamic status is first assessed, and resuscitation initiated as needed. Patients are risk-stratified based on features such as hemodynamic status, comorbidities, age, and laboratory tests. Pre-endoscopic erythromycin is considered to increase diagnostic yield at first endoscopy. Pre-endoscopic proton pump inhibitor (PPI) may be considered to decrease the need for endoscopic therapy but does not improve clinical outcomes. Upper endoscopy is generally performed within 24h. The endoscopic features of ulcers direct further management. Patients with active bleeding or non-bleeding visible vessels receive endoscopic therapy (e.g., bipolar electrocoagulation, heater probe, sclerosant, clips) and those with an adherent clot may receive endoscopic therapy; these patients then receive intravenous PPI with a bolus followed by continuous infusion. Patients with flat spots or clean-based ulcers do not require endoscopic therapy or intensive PPI therapy. Recurrent bleeding after endoscopic therapy is treated with a second endoscopic treatment; if bleeding persists or recurs, treatment with surgery or interventional radiology is undertaken. Prevention of recurrent bleeding is based on the etiology of the bleeding ulcer. H. pylori is eradicated and after cure is documented anti-ulcer therapy is generally not given. Nonsteroidal anti-inflammatory drugs (NSAIDs) are stopped; if they must be resumed low-dose COX-2-selective NSAID plus PPI is used. Patients with established cardiovascular disease who require aspirin should start PPI and generally re-institute aspirin soon after bleeding ceases (within 7 days and ideally 1-3 days). Patients with idiopathic ulcers receive long-term anti-ulcer therapy.

  6. Engine bleed air reduction in DC-10

    Science.gov (United States)

    Newman, W. H.; Viele, M. R.

    1980-01-01

    An 0.8 percent fuel savings was achieved by a reduction in engine bleed air through the use of cabin air recirculation. The recirculation system was evaluated in revenue service on a DC-10. The cabin remained comfortable with reductions in cabin fresh air (engine bleed air) as much as 50 percent. Flight test verified the predicted fuel saving of 0.8 percent.

  7. Helping mothers survive bleeding after birth

    DEFF Research Database (Denmark)

    Nelissen, Ellen; Ersdal, Hege; Ostergaard, Doris

    2014-01-01

    OBJECTIVE: To evaluate "Helping Mothers Survive Bleeding After Birth" (HMS BAB) simulation-based training in a low-resource setting. DESIGN: Educational intervention study. SETTING: Rural referral hospital in Northern Tanzania. POPULATION: Clinicians, nurse-midwives, medical attendants, and ambul......OBJECTIVE: To evaluate "Helping Mothers Survive Bleeding After Birth" (HMS BAB) simulation-based training in a low-resource setting. DESIGN: Educational intervention study. SETTING: Rural referral hospital in Northern Tanzania. POPULATION: Clinicians, nurse-midwives, medical attendants...

  8. Transcatheter emboilization therapy of massive colonic bleeding

    International Nuclear Information System (INIS)

    Shin, G. H.; Oh, J. H.; Yoon, Y.

    1996-01-01

    To evaulate the efficacy and safety of emergent superselective transcatheter embolization for controlling massive colonic bleeding. Six of the seven patients who had symptom of massive gastrointestinal bleeding underwent emergent transcatheter embolization for control of the bleeding. Gastrointestinal bleeding in these patients was originated from various colonic diseases: rectal cancer(n=1), proctitis(n=1), benign ulcer(n=1), mucosal injury by ventriculoperitoneal shunt(n=1), and unknown(n=2). All patients except one with rectal cancer were critically ill. Superselective embolization were done by using Gelfoam particles and/or coils. The vessels embolized were ileocolic artery(n=1). superior rectal artery(n=2), inferior rectal artery (n=1), and middle and inferior rectal arteries(n=1). Hemostasis was successful immediately in all patients. Two underwnet surgery due to recurrent bleeding developed 3 days after the procedure(n=1) or in associalion with underlying rectal cancer(n=1). On surgical specimen of two cases, there was no mucosal ischemic change. Transcatheter embolization is a safe and effective treatment of method for the control of massive colonic bleeding

  9. [Hysteroscopic polypectomy, treatment of abnormal uterine bleeding].

    Science.gov (United States)

    de Los Rios, P José F; López, R Claudia; Cifuentes, P Carolina; Angulo, C Mónica; Palacios-Barahona, Arlex U

    2015-07-01

    To evaluate the effectiveness of the hysteroscopic polypectomy in terms of the decrease of the abnormal uterine bleeding. A cross-sectional and analytical study was done with patients to whom a hysteroscopic polypectomy was done for treating the abnormal uterine bleeding, between January 2009 and December 2013. The response to the treatment was evaluated via a survey given to the patients about the behavior of the abnormal uterine bleeding after the procedure and about overall satisfaction. The results were obtained after a hysteroscopic polypectomy done to 128 patients and were as follows. The average time from the polypectomy applied until the survey was 30.5 months, with a standard deviation of 18 months. 67.2% of the patients reported decreased abnormal uterine bleeding and the 32.8% reported a persistence of symptoms. On average 82.8% of the. patients were satisfied with the treatment. Bivariate and multivariate analysis showed no association between the variables studied and no improvement of abnormal uterine bleeding after surgery (polypectomy). There were no complications. Hysteroscopic polypectomy is a safe surgical treatment, which decreases on two of three patients the abnormal uterine bleeding in the presence of endometrial polyps, with an acceptable level of satisfaction.

  10. Fatigue Behavior of Modified Asphalt Concrete Pavement

    Directory of Open Access Journals (Sweden)

    saad I. Sarsam

    2016-02-01

    Full Text Available Fatigue cracking is the most common distress in road pavement. It is mainly due to the increase in the number of load repetition of vehicles, particularly those with high axle loads, and to the environmental conditions. In this study, four-point bending beam fatigue testing has been used for control and modified mixture under various micro strain levels of (250 μƐ, 400 μƐ, and 750 μƐ and 5HZ. The main objective of the study is to provide a comparative evaluation of pavement resistance to the phenomenon of fatigue cracking between modified asphalt concrete and conventional asphalt concrete mixes (under the influence of three percentage of Silica fumes 1%, 2%, 3% by the weight of asphalt content, and (changing in the percentage of asphalt content by (0.5% ± from the optimum. The results show that when Silica fumes content was 1%, the fatigue life increases by 17%, and it increases by 46% when Silica fumes content increases to 2%, and that fatigue life increases to 34 % when Silica fumes content increases to 3% as compared with control mixture at (250 μƐ, 20°C and optimum asphalt content. From the results above, we can conclude the optimum Silica fumes content was 2%. When the asphalt content was 4.4%, the fatigue life has increased with the use of silica fumes by (50%, when asphalt content was 5.4%, the additives had led to increasing the fatigue life by (69%, as compared with the conventional asphalt concrete pavement.

  11. Bleeding and starving: fasting and delayed refeeding after upper gastrointestinal bleeding.

    Science.gov (United States)

    Fonseca, Jorge; Meira, Tânia; Nunes, Ana; Santos, Carla Adriana

    2014-01-01

    Early refeeding after nonvariceal upper gastrointestinal bleeding is safe and reduces hospital stay/costs. The aim of this study was obtaining objective data on refeeding after nonvariceal upper gastrointestinal bleeding. From 1 year span records of nonvariceal upper gastrointestinal bleeding patients that underwent urgent endoscopy: clinical features; rockall score; endoscopic data, including severity of lesions and therapy; feeding related records of seven days: liquid diet prescription, first liquid intake, soft/solid diet prescription, first soft/solid intake. From 133 patients (84 men) Rockall classification was possible in 126: 76 score ≥5, 50 score gastrointestinal bleeding patients must be refed earlier, according to guidelines.

  12. Antifibrinolytics for heavy menstrual bleeding.

    Science.gov (United States)

    Bryant-Smith, Alison C; Lethaby, Anne; Farquhar, Cindy; Hickey, Martha

    2018-04-15

    Heavy menstrual bleeding (HMB) is an important physical and social problem for women. Oral treatment for HMB includes antifibrinolytic drugs, which are designed to reduce bleeding by inhibiting clot-dissolving enzymes in the endometrium.Historically, there has been some concern that using the antifibrinolytic tranexamic acid (TXA) for HMB may increase the risk of venous thromboembolic disease. This is an umbrella term for deep venous thrombosis (blood clots in the blood vessels in the legs) and pulmonary emboli (blood clots in the blood vessels in the lungs). To determine the effectiveness and safety of antifibrinolytic medications as a treatment for heavy menstrual bleeding. We searched the Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO and two trials registers in November 2017, together with reference checking and contact with study authors and experts in the field. We included randomized controlled trials (RCTs) comparing antifibrinolytic agents versus placebo, no treatment or other medical treatment in women of reproductive age with HMB. Twelve studies utilised TXA and one utilised a prodrug of TXA (Kabi). We used standard methodological procedures expected by Cochrane. The primary review outcomes were menstrual blood loss (MBL), improvement in HMB, and thromboembolic events. We included 13 RCTs (1312 participants analysed). The evidence was very low to moderate quality: the main limitations were risk of bias (associated with lack of blinding, and poor reporting of study methods), imprecision and inconsistency.Antifibrinolytics (TXA or Kabi) versus no treatment or placeboWhen compared with a placebo, antifibrinolytics were associated with reduced mean blood loss (MD -53.20 mL per cycle, 95% CI -62.70 to -43.70; I² = 8%; 4 RCTs, participants = 565; moderate-quality evidence) and higher rates of improvement (RR 3.34, 95% CI 1.84 to 6.09; 3 RCTS, participants = 271; moderate-quality evidence). This suggests that

  13. Viscoelastic Pavement Modeling with a Spreadsheet

    DEFF Research Database (Denmark)

    Levenberg, Eyal

    2016-01-01

    The aim herein was to equip civil engineers and students with an advanced pavement modeling tool that is both easy to use and highly adaptive. To achieve this, a mathematical solution for a layered viscoelastic half-space subjected to a moving load was developed and subsequently implemented...... in a spreadsheet environment. The final program can consider up to five fully bonded layers, each isotropic, homogeneous and weightless. The top layer (as well as others if desired) is linear viscoelastic, while the remaining layers are linear elastic. The load is applied vertically to the surface of the system...

  14. The Inhabitants of the Historical Pavement

    DEFF Research Database (Denmark)

    2016-01-01

    Video: 5 min.This excerpt from the shortfilm Accumulations (2016) is part of Espen Lunde Nielsens PhD-project Architectural Probes of the Infraordinary (2013-2016). The shortfilm explores the (infra-)ordinary versus the extraordinary collective memory of the built environment: From cathedrals...... and boulevards to kiosks and cigarette packs.This particular excerpt presents a framed view of a quasi-historical pavement in downtown Chicago and the coming and going of people. Some are passing by without paying much attention, for others it is their daily workplace and for some an exotic starting point...

  15. The leaf phenophase of deciduous species altered by land pavements

    Science.gov (United States)

    Chen, Yuanyuan; Wang, Xiaoke; Jiang, Bo; Li, Li

    2018-02-01

    It has been widely reported that the urban environment alters leaf and flowering phenophases; however, it remains unclear if land pavement is correlated with these alterations. In this paper, two popular deciduous urban trees in northern China, ash (Fraxinus chinensis) and maple (Acer truncatum), were planted in pervious and impervious pavements at three spacings (0.5 m × 0.5 m, 1.0 m × 1.0 m, and 2.0 m × 2.0 m apart). The beginning and end dates of the processes of leaf budburst and senescence were recorded in spring and fall of 2015, respectively. The results show that leaf budburst and senescence were significantly advanced in pavement compared to non-pavement lands. The date of full leaf budburst was earlier by 0.7-9.3 days for ash and by 0.3-2.3 days for maple under pavements than non-pavements, respectively. As tree spacing increases, the advanced days of leaf budburst became longer. Our results clearly indicate that alteration of leaf phenophases is attributed to land pavement, which should be taken into consideration in urban planning and urban plant management.

  16. Flood Mitigation by Permeable Pavements in Chinese Sponge City Construction

    Directory of Open Access Journals (Sweden)

    Maochuan Hu

    2018-02-01

    Full Text Available It is important to evaluate the effectiveness of permeable pavements on flood mitigation at different spatial scales for their effective application, for example, sponge city construction in China. This study evaluated the effectiveness of three types of permeable pavements (i.e., permeable asphalts (PA, permeable concretes (PC, and permeable interlocking concrete pavers (PICP on flood mitigation at a community scale in China using a hydrological model. In addition, the effects of clogging and initial water content in permeable pavements on flood mitigation performance were assessed. The results indicated that in 12 scenarios, permeable pavements reduced total surface runoff by 1–40% and peak flow by 7–43%, respectively. The hydrological performance of permeable pavements was limited by clogging and initial water content. Clogging resulted in the effectiveness on total surface runoff reduction and peak flow reduction being decreased by 62–92% and 37–65%, respectively. By increasing initial water content at the beginning of the simulation, the effectiveness of total runoff reduction and peak flow reduction decreased by 57–85% and 37–67%, respectively. Overall, among the three types of permeable pavements, PC without clogging had the best performance in terms of flood mitigation, and PICP was the least prone to being clogged. Our findings demonstrate that both the type and the maintenance of permeable pavements have significant effects on their performance in the flood mitigation.

  17. Pavement cracking measurements using 3D laser-scan images

    International Nuclear Information System (INIS)

    Ouyang, W; Xu, B

    2013-01-01

    Pavement condition surveying is vital for pavement maintenance programs that ensure ride quality and traffic safety. This paper first introduces an automated pavement inspection system which uses a three-dimensional (3D) camera and a structured laser light to acquire dense transverse profiles of a pavement lane surface when it carries a moving vehicle. After the calibration, the 3D system can yield a depth resolution of 0.5 mm and a transverse resolution of 1.56 mm pixel −1 at 1.4 m camera height from the ground. The scanning rate of the camera can be set to its maximum at 5000 lines s −1 , allowing the density of scanned profiles to vary with the vehicle's speed. The paper then illustrates the algorithms that utilize 3D information to detect pavement distress, such as transverse, longitudinal and alligator cracking, and presents the field tests on the system's repeatability when scanning a sample pavement in multiple runs at the same vehicle speed, at different vehicle speeds and under different weather conditions. The results show that this dedicated 3D system can capture accurate pavement images that detail surface distress, and obtain consistent crack measurements in repeated tests and under different driving and lighting conditions. (paper)

  18. Surgical treatment of massive upper gastrointestinal bleeding in ...

    African Journals Online (AJOL)

    Acute upper gastrointestinal bleeding is a potentially life-threatening abdominal emergency condition. More immediately life-threatening is massive upper gastrointestinal bleeding resulting in cardiovascular compromise causing dizziness, syncope and shock. The causes of upper gastrointestinal bleeding include bleeding ...

  19. Predicting major bleeding in patients with noncardioembolic stroke on antiplatelets: S2TOP-BLEED.

    Science.gov (United States)

    Hilkens, Nina A; Algra, Ale; Diener, Hans-Christoph; Reitsma, Johannes B; Bath, Philip M; Csiba, Laszlo; Hacke, Werner; Kappelle, L Jaap; Koudstaal, Peter J; Leys, Didier; Mas, Jean-Louis; Sacco, Ralph L; Amarenco, Pierre; Sissani, Leila; Greving, Jacoba P

    2017-08-29

    To develop and externally validate a prediction model for major bleeding in patients with a TIA or ischemic stroke on antiplatelet agents. We combined individual patient data from 6 randomized clinical trials (CAPRIE, ESPS-2, MATCH, CHARISMA, ESPRIT, and PRoFESS) investigating antiplatelet therapy after TIA or ischemic stroke. Cox regression analyses stratified by trial were performed to study the association between predictors and major bleeding. A risk prediction model was derived and validated in the PERFORM trial. Performance was assessed with the c statistic and calibration plots. Major bleeding occurred in 1,530 of the 43,112 patients during 94,833 person-years of follow-up. The observed 3-year risk of major bleeding was 4.6% (95% confidence interval [CI] 4.4%-4.9%). Predictors were male sex, smoking, type of antiplatelet agents (aspirin-clopidogrel), outcome on modified Rankin Scale ≥3, prior stroke, high blood pressure, lower body mass index, elderly, Asian ethnicity, and diabetes (S 2 TOP-BLEED). The S 2 TOP-BLEED score had a c statistic of 0.63 (95% CI 0.60-0.64) and showed good calibration in the development data. Major bleeding risk ranged from 2% in patients aged 45-54 years without additional risk factors to more than 10% in patients aged 75-84 years with multiple risk factors. In external validation, the model had a c statistic of 0.61 (95% CI 0.59-0.63) and slightly underestimated major bleeding risk. The S 2 TOP-BLEED score can be used to estimate 3-year major bleeding risk in patients with a TIA or ischemic stroke who use antiplatelet agents, based on readily available characteristics. The discriminatory performance may be improved by identifying stronger predictors of major bleeding. © 2017 American Academy of Neurology.

  20. Development of Improved Mechanistic Deterioration Models for Flexible Pavements

    DEFF Research Database (Denmark)

    Ullidtz, Per; Ertman, Hans Larsen

    1998-01-01

    The paper describes a pilot study in Denmark with the main objective of developing improved mechanistic deterioration models for flexible pavements based on an accelerated full scale test on an instrumented pavement in the Danish Road Tessting Machine. The study was the first in "International...... Pavement Subgrade Performance Study" sponsored by the Federal Highway Administration (FHWA), USA. The paper describes in detail the data analysis and the resulting models for rutting, roughness, and a model for the plastic strain in the subgrade.The reader will get an understanding of the work needed...

  1. Validation of theoretical models through measured pavement response

    DEFF Research Database (Denmark)

    Ullidtz, Per

    1999-01-01

    mechanics was quite different from the measured stress, the peak theoretical value being only half of the measured value.On an instrumented pavement structure in the Danish Road Testing Machine, deflections were measured at the surface of the pavement under FWD loading. Different analytical models were...... then used to derive the elastic parameters of the pavement layeres, that would produce deflections matching the measured deflections. Stresses and strains were then calculated at the position of the gauges and compared to the measured values. It was found that all analytical models would predict the tensile...

  2. Dynamic Modeling of Pavements with Application to Deflection Measurements

    DEFF Research Database (Denmark)

    Madsen, Stine Skov

    Pavement surface deflection measurements are the primary means of evaluating the bearing capacity of a pavement. The most common type of device used for measuring pavement surface deflections is the Falling Weight Deflectometer (FWD). However, increasing attention has been given to the Rolling Wheel...... with different speeds is needed. In this thesis a new Finite Element formulation for transient dynamic loading of a layered half space is developed. Equations are derived in 2D and 3D and include efficient absorbing boundary conditions in the form of the Perfectly Matched Layer (PML) which ensures capability...

  3. An Innovative Cellular Automata Technique for Mapping Cracking Pattern of Airport Pavement

    Directory of Open Access Journals (Sweden)

    Yin Fucheng

    2017-01-01

    Full Text Available In this study, an innovative cellular automata (CA technique was proposed for mapping cracking pattern of the airport pavement. The CA technique was developed to establish a numerical model describing the effect of boundary condition of pavement on zones (CA cells within the pavement. A state function was used to describe the state values in the cells within the CA lattice. The correction coefficient principle is used as the criterion of zone similarity and the corresponding technique is proposed to find similar zones within and between pavements. Three pavement models, HRS, MRS and LRS, tested in FAA, USA, are set as the base pavements to map the cracking patterns of pavements with different sizes from the base pavements. The mapped cracking patterns of unseen pavements are empirically verified by referring to the relative experimental models.

  4. The comparisons of computational models of pavement due to the dynamic load act

    Directory of Open Access Journals (Sweden)

    Valašková Veronika

    2017-01-01

    Full Text Available Finite element method (FEM is frequently used to solve current problems of the structural mechanics in engineering practice. The dynamic interaction of the two systems is one of the topics that can be solved using FEM. To simplify the solution of the interaction, it is possible to divide the system in two independent subsystems, vehicle and pavement. Computing software ADINA, based on the principles of the finite element modelling, was adopted to solve the given problem. The results from the first computational model can be used as the inputs for the second model. To analyse stress state of the pavement with different composition, three specific types of pavements were selected – concrete pavement, semi-rigid pavement and flexible pavement. The pavements represent the typical pavement types used for the regular road structures. This article is focused on the analysis of the stress state and the displacements of the pavement induced by the moving load from the traffic.

  5. An assessment of the feasibility of developing and implementing an automated pavement distress survey system incorporating digital image processing.

    Science.gov (United States)

    1997-01-01

    The rational allocation of pavement maintenance resources requires the periodic assessment of the condition of all pavements. Traditional manual pavement distress surveys, which are based on visual inspection, are labor intensive, slow, and expensive...

  6. Laboratory data to determine impact of coarse aggregate type and cementitious materials on design thickness of PCC pavements.

    Science.gov (United States)

    2016-12-01

    The Mississippi Department of Transportation (MDOT) needed mechanical and volume change properties of portland cement concrete (PCC) pavement in order to implement pavement thickness design procedures of the Mechanistic-Empirical Pavement Design Guid...

  7. Predictive design procedures, VESYS users manual : an interim design method for flexible pavements using the VESYS structural subsystem

    Science.gov (United States)

    1978-01-01

    This manual has been written to provide the pavement manager and design engineer with a ready reference of procedures to predict the structural responses and hence the integrity of flexible pavements. A pavement section of known geometry is chosen, a...

  8. Long-term Performance of Granular Bases Including the Effect of Wet-Dry Cycles on Inverted Base Pavement Performance

    Science.gov (United States)

    2017-06-01

    The main objective of this study was to advance the understanding of alternative pavement designs. In particular, potential techniques such as inverted base pavements (IBP) have increased the importance of granular aggregate bases (GAB) in pavement s...

  9. Cost-Effective Pavement Performance Management of Indiana's Enhanced National Highway System through Strategic Modification of the Pavement Rehabilitation Treatment Trigger Values

    OpenAIRE

    Noureldin, Menna; Fricker, Jon D.; Sinha, Kumares C.

    2015-01-01

    Cost-Effective Pavement Performance Management of Indiana's Enhanced National Highway System through Strategic Modification of the Pavement Rehabilitation Treatment Trigger Values Presented during Session 3: Policy and Funding, moderated by Magdy Mikhail, at the 9th International Conference on Managing Pavement Assets (ICMPA9) in Alexandria, VA. Includes conference paper and PowerPoint slides.

  10. Climate change, energy, sustainability and pavements

    International Nuclear Information System (INIS)

    Gopalakrishnan, Kasthurirangan; Steyn, Wynand JvdM; Harvey, John

    2014-01-01

    Provides an integrated perspective on understanding the impacts of climate change, energy and sustainable development on transportation infrastructure systems. Presents recent technological innovations and emerging concepts in the field of green and sustainable transportation infrastructure systems with a special focus on highway and airport pavements. Written by leading experts in the field. Climate change, energy production and consumption, and the need to improve the sustainability of all aspects of human activity are key inter-related issues for which solutions must be found and implemented quickly and efficiently. To be successfully implemented, solutions must recognize the rapidly changing socio-techno-political environment and multi-dimensional constraints presented by today's interconnected world. As part of this global effort, considerations of climate change impacts, energy demands, and incorporation of sustainability concepts have increasing importance in the design, construction, and maintenance of highway and airport pavement systems. To prepare the human capacity to develop and implement these solutions, many educators, policy-makers and practitioners have stressed the paramount importance of formally incorporating sustainability concepts in the civil engineering curriculum to educate and train future civil engineers well-equipped to address our current and future sustainability challenges. This book will prove a valuable resource in the hands of researchers, educators and future engineering leaders, most of whom will be working in multidisciplinary environments to address a host of next-generation sustainable transportation infrastructure challenges.

  11. Climate change, energy, sustainability and pavements

    Energy Technology Data Exchange (ETDEWEB)

    Gopalakrishnan, Kasthurirangan [Iowa State Univ., Ames, IA (United States). Dept. of Civil, Construction and Environmental Engineering; Steyn, Wynand JvdM [Pretoria Univ. (South Africa). Dept. of Civil Engineering; Harvey, John (ed.) [California Univ., Davis, CA (United States). Dept. of Civil and Environmental Engineering

    2014-07-01

    Provides an integrated perspective on understanding the impacts of climate change, energy and sustainable development on transportation infrastructure systems. Presents recent technological innovations and emerging concepts in the field of green and sustainable transportation infrastructure systems with a special focus on highway and airport pavements. Written by leading experts in the field. Climate change, energy production and consumption, and the need to improve the sustainability of all aspects of human activity are key inter-related issues for which solutions must be found and implemented quickly and efficiently. To be successfully implemented, solutions must recognize the rapidly changing socio-techno-political environment and multi-dimensional constraints presented by today's interconnected world. As part of this global effort, considerations of climate change impacts, energy demands, and incorporation of sustainability concepts have increasing importance in the design, construction, and maintenance of highway and airport pavement systems. To prepare the human capacity to develop and implement these solutions, many educators, policy-makers and practitioners have stressed the paramount importance of formally incorporating sustainability concepts in the civil engineering curriculum to educate and train future civil engineers well-equipped to address our current and future sustainability challenges. This book will prove a valuable resource in the hands of researchers, educators and future engineering leaders, most of whom will be working in multidisciplinary environments to address a host of next-generation sustainable transportation infrastructure challenges.

  12. Automated management for pavement inspection system (AMPIS)

    Science.gov (United States)

    Chung, Hung Chi; Girardello, Roberto; Soeller, Tony; Shinozuka, Masanobu

    2003-08-01

    An automated in-situ road surface distress surveying and management system, AMPIS, has been developed on the basis of video images within the framework of GIS software. Video image processing techniques are introduced to acquire, process and analyze the road surface images obtained from a moving vehicle. ArcGIS platform is used to integrate the routines of image processing and spatial analysis in handling the full-scale metropolitan highway surface distress detection and data fusion/management. This makes it possible to present user-friendly interfaces in GIS and to provide efficient visualizations of surveyed results not only for the use of transportation engineers to manage road surveying documentations, data acquisition, analysis and management, but also for financial officials to plan maintenance and repair programs and further evaluate the socio-economic impacts of highway degradation and deterioration. A review performed in this study on fundamental principle of Pavement Management System (PMS) and its implementation indicates that the proposed approach of using GIS concept and its tools for PMS application will reshape PMS into a new information technology-based system providing a convenient and efficient pavement inspection and management.

  13. Application of Conductive Materials to Asphalt Pavement

    Directory of Open Access Journals (Sweden)

    Hai Viet Vo

    2017-01-01

    Full Text Available Snow-melting pavement technique is an advanced preservation method, which can prevent the forming of snow or ice on the pavement surface by increasing the temperature using an embedded heating system. The main scope of this study is to evaluate the impact of conductive additives on the heating efficiency. The electrical resistivity and thermal conductivity were considered to investigate effects of conductive additives, graphite, and carbon fibers on the snow-melting ability of asphalt mixtures. Also, the distribution of the conductive additives within the asphalt concrete body was investigated by microstructural imaging. An actual test was applied to simulate realistic heating for an asphalt concrete mixture. Thermal testing indicated that graphite and carbon fibers improve the snow-melting ability of asphalt mixes and their combination is more effective than when used alone. As observed in the microstructural image, carbon fibers show a long-range connecting effect among graphite conductive clusters and gather in bundles when added excessively. According to the actual test, adding the conductive additives helps improve snow-melting efficiency by shortening processing time and raising the surface temperature.

  14. Interventions for treating post-extraction bleeding.

    Science.gov (United States)

    Kumbargere Nagraj, Sumanth; Prashanti, Eachempati; Aggarwal, Himanshi; Lingappa, Ashok; Muthu, Murugan S; Kiran Kumar Krishanappa, Salian; Hassan, Haszelini

    2018-03-04

    Post-extraction bleeding (PEB) is a recognised, frequently encountered complication in dental practice, which is defined as bleeding that continues beyond 8 to 12 hours after dental extraction. The incidence of post-extraction bleeding varies from 0% to 26%. If post-extraction bleeding is not managed, complications can range from soft tissue haematomas to severe blood loss. Local causes of bleeding include soft tissue and bone bleeding. Systemic causes include platelet problems, coagulation disorders or excessive fibrinolysis, and inherited or acquired problems (medication induced). There is a wide array of techniques suggested for the treatment of post-extraction bleeding, which include interventions aimed at both local and systemic causes. This is an update of a review published in June 2016. To assess the effects of interventions for treating different types of post-extraction bleeding. Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 24 January 2018), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 12), MEDLINE Ovid (1946 to 24 January 2018), Embase Ovid (1 May 2015 to 24 January 2018) and CINAHL EBSCO (1937 to 24 January 2018). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. We searched the reference lists of relevant systematic reviews. We considered randomised controlled trials (RCTs) that evaluated any intervention for treating PEB, with male or female participants of any age, regardless of type of teeth (anterior or posterior, mandibular or maxillary). Trials could compare one type of intervention with another, with placebo, or with no treatment. Three pairs of review authors independently screened search records. We obtained full papers for potentially relevant trials. If data had been extracted

  15. Secondary electric power generation with minimum engine bleed

    Science.gov (United States)

    Tagge, G. E.

    1983-01-01

    Secondary electric power generation with minimum engine bleed is discussed. Present and future jet engine systems are compared. The role of auxiliary power units is evaluated. Details of secondary electric power generation systems with and without auxiliary power units are given. Advanced bleed systems are compared with minimum bleed systems. A cost model of ownership is given. The difference in the cost of ownership between a minimum bleed system and an advanced bleed system is given.

  16. Reliability measures in managing GI bleeding.

    Science.gov (United States)

    Sonnenberg, Amnon

    2012-06-01

    Multiple procedures and devices are used in a complex interplay to diagnose and treat GI bleeding. To model how a large variety of diagnostic and therapeutic components interact in the successful management of GI bleeding. The analysis uses the concept of reliability block diagrams from probability theory to model management outcome. Separate components of the management process are arranged in a serial or parallel fashion. If the outcome depends on the function of each component individually, such components are modeled to be arranged in series. If components complement each other and can mutually compensate for each of their failures, such components are arranged in a parallel fashion. General endoscopy practice. Patients with GI bleeding of unknown etiology. All available endoscopic and radiographic means to diagnose and treat GI bleeding. Process reliability in achieving hemostasis. Serial arrangements tend to reduce process reliability, whereas parallel arrangements increase it. Whenever possible, serial components should be bridged and complemented by additional alternative (parallel) routes of operation. Parallel components with low individual reliability can still contribute to overall process reliability as long as they function independently of other pre-existing alternatives. Probability of success associated with individual components is partly unknown. Modeling management of GI bleeding by a reliability block diagram provides a useful tool in assessing the impact of individual endoscopic techniques and administrative structures on the overall outcome. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  17. [Update on non-variceal gastrointestinal bleeding].

    Science.gov (United States)

    Lanas, Ángel

    2013-10-01

    This article summarizes the main studies in the field of non-variceal gastrointestinal bleeding reported in the last American Congress of Gastroenterology (Digestive Disease Week) in 2013. Some of these studies have provided new knowledge and expertise in areas of uncertainty. In this context and among other findings, it has been reported that the administration of a proton pump inhibitor (PPI) prior to endoscopy or the early performance of endoscopy-within 6 hours of admission in patients with upper gastrointestinal bleeding (UGIB) (or colonoscopy within 24 hours in patients with lower gastrointestinal bleeding)-does not improve the prognosis of the event. It has also been reported that oral administration of a PPI after endoscopic hemostasis may produce a similar outcome to that of intravenously administered PPI in patients with upper gastrointestinal bleeding (UGIB). In the field of endoscopic therapy, the use of radiofrequency ablation for antral vascular ectasia is of interest. Regarding UGIB and nonsteroidal antiinflammatory drugs (NSAIDs), new data confirm the risk of cardiovascular events by stopping treatment with acetylsalicylic acid (ASA) after an episode of UGIB, the increased risk of UGIB when associating gastrotoxic drugs, and the need to identify both the gastrointestinal and cardiovascular risks of each NSAID and coxib when prescribing these agents. Finally, there is evidence that both environmental and genetic factors are involved in individual susceptibility to gastrointestinal bleeding. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  18. Effect of friction on rolling tire-pavement interaction.

    Science.gov (United States)

    2010-11-01

    Accurate modeling of tirepavement contact behavior (i.e., distribution of contact tractions at the : interface) plays an important role in the analysis of pavement performance and vehicle driving safety. : The tirepavement contact is essentiall...

  19. Longitudinal cracking in widened portland cement concrete pavements.

    Science.gov (United States)

    2013-02-01

    The Wisconsin Department of Transportation constructed certain concrete pavements with lane widths greater : than the standard 12 feet in order to reduce stress and deflection caused by vehicle tires running near the edge of : the concrete slabs. Man...

  20. Portland cement concrete pavement restoration : final summary report.

    Science.gov (United States)

    1988-07-01

    This final summary report is comprised of an Initial Construction Report; a Final Report; and two Interim Reports. These reports document the construction of Louisiana's Portland Cement Concrete Pavement Restoration project and its performance during...

  1. Use of nonwoven geotextiles as interlayers in concrete pavement systems.

    Science.gov (United States)

    2009-05-01

    This document describes the potential use of nonwoven geotextile materials as interlayers in concrete pavement systems, particularly unbonded overlays, in the United States. It briefly discusses Germanys experience, availability and cost of nonwov...

  2. Prediction of thermal behavior of pervious concrete pavements in winter.

    Science.gov (United States)

    2017-05-15

    Because application of pervious concrete pavement (PCPs) has extended to cold-climate regions of the United States, the safety and : mobility of PCP installations during the winter season need to be maintained. Timely application of salt, anti-icing,...

  3. Inferring pavement layer properties from a moving measurement platform

    DEFF Research Database (Denmark)

    Andersen, Sebastian; Levenberg, Eyal; Andersen, M.B.

    2017-01-01

    This work offered a new method for accessing the mechanical properties of pavement layers based on data obtained by a moving measurement platform. The method has the following features: (i) calculations are based on tracking distances to a point on the pavement surface, (ii) measurements...... are not required outside the zone of load influence, and (iii) possibility to access absolute pavement deflections. First, the envisioned platform-design and required readings were presented; next, the interpretation method was outlined and then applied to synthetic (computer-generated) data. Perfect convergence...... was achieved when the correct pavement model and accurate input data were employed. Also, when artificial errors were introduced for assessing sensitivities, only small deviations were generated. Based on these promising outcomes the method will be further studied and developed to support the construction...

  4. Laboratory evaluation of characteristics of recycled asphalt pavement in Kansas.

    Science.gov (United States)

    2011-09-01

    The main objective of this research was to evaluate characteristics of milled Recycled Asphalt : Pavements (RAP) collected from selected milled roadways in Kansas. The RAP was collected from three : selected milled roadways including K-25 in Grant Co...

  5. Forensic analysis of asphaltic pavement failures in Ghana: case histories

    CSIR Research Space (South Africa)

    Ampadu, SIK

    2015-08-01

    Full Text Available Many newly constructed asphaltic pavements in Ghana have suffered premature failures shortly after opening to traffic. In all cases, available records from the road agencies appeared to show that the roads were constructed in accordance...

  6. Mobile geographic information system (GIS) solution for pavement condition surveys.

    Science.gov (United States)

    2012-06-28

    This report discusses the design and implementation of a software-based solution that will improve the data collection processes during the Pavement Condition Surveys (PCS) conducted by the State Materials Office (SMO) of the Florida Department of Tr...

  7. Implementation of warm-mix asphalt mixtures in Nebraska pavements.

    Science.gov (United States)

    2012-07-01

    The primary objective of this research is to evaluate the feasibility of several WMA mixtures as potential asphalt paving : mixtures for Nebraska pavements. To that end, three well-known WMA additives (i.e., Sasobit, Evotherm, and Advera : synthetic ...

  8. Evaluation of reclaimed asphalt pavement for surface mixtures.

    Science.gov (United States)

    2012-03-01

    The Indiana Department of Transportation has successfully used Reclaimed Asphalt Pavement (RAP) for decades because of its economic : and environmental benefits. Because of uncertainties regarding the types of aggregates contained in RAP and their re...

  9. Evaluation of reclaimed asphalt pavement for surface mixtures : [technical summary].

    Science.gov (United States)

    2012-01-01

    The Indiana Department of Transportation (INDOT) has successfully used Reclaimed Asphalt Pavement (RAP) for decades because of its economic and environmental benefits. However, until recently, INDOT has disallowed the use of RAP in asphalt surface mi...

  10. Evaluation of construction strategies for PCC pavement rehabilitation projects.

    Science.gov (United States)

    2010-09-30

    This study investigated project management level solutions to optimizing resources, minimizing costs : (including user costs) and time for PCC pavement rehabilitation projects. This study extensively : evaluated the applicability of the Construction ...

  11. Evaluation of transverse joint forming methods for PCC pavement.

    Science.gov (United States)

    2006-01-01

    The members of the Iowa Concrete Paving Association, the National Concrete Pavement Technology Center Research Committee, and : the Iowa Highway Research Board commissioned a study to examine alternative ways of developing transverse joints in portla...

  12. Recycling Old PCC Pavement - Performance Evaluation of FAI 57 Inlays

    Science.gov (United States)

    1993-02-01

    This report details the construction and performance monitoring efforts of two demonstration projects proposed in an experimental features work plan entitled Recycling Old PCC Pavement". The objectives of this experimental feature were to evaluate th...

  13. Long term monitoring of moisture under pavements : executive summary report.

    Science.gov (United States)

    2010-01-01

    The research : program consisted of three : distinct : activities. The first activity was a continuation of : the monitoring of environmental instrumentation : under select pavement sections constructed by the : Ohio Department of Transportation (ODO...

  14. Texas pavement preservation center two-year summary report.

    Science.gov (United States)

    2011-08-01

    Established August 11, 2005, The TPPC serves the broad range of needs of the Texas Department of Transportation (TxDOT), and other agencies within the highway community by promoting awareness of pavement preservation as a feasible and practical maint...

  15. Texas pavement preservation center four-year summary report.

    Science.gov (United States)

    2009-07-04

    The Texas Pavement Preservation Center (TPPC), in joint collaboration with the Center for Transportation Research (CTR) of the University of Texas at Austin and the Texas Transportation Institute (TTI) of Texas A&M University, promotes the use of pav...

  16. Tack coat optimization for HMA overlays : accelerated pavement test report.

    Science.gov (United States)

    2009-02-01

    Interface bonding between hot-mix asphalt (HMA) overlays and Portland cement concrete (PCC) pavements is one : of the most significant factors affecting overlay service life. This study was performed to quantify the effects of HMA type, : tack coat t...

  17. Evaluation of the use of snowplowable raised pavement markers.

    Science.gov (United States)

    2009-04-01

    The objective of this study was to evaluate the effectiveness and durability of snowplowable raised pavement markers (RPM) installed on the RPM system in Kentucky. The durability evaluation dealt wit the marker housing. : The data show that continued...

  18. Use of nondestructive evaluation to detect moisture in flexible pavements.

    Science.gov (United States)

    2006-01-01

    The purpose of this study was to identify the currently available nondestructive evaluation technology that holds the greatest potential to detect moisture in flexible pavements and then apply the technology in multiple locations throughout Virginia....

  19. Evaluation of portable retroreflectometer for use on pavement marking materials.

    Science.gov (United States)

    1981-01-01

    The subjective rating of the night visibility of pavement marking materials is difficult as it can be influenced by many variables. In an attempt to provide an improved method of determining the night visibility of these materials, a portable retrore...

  20. Development of an automated pavement crack sealing system.

    Science.gov (United States)

    2010-12-01

    Pavement crack sealing operations remain predominantly manual due to the challenges associated with automation. The research : performed by the Georgia Tech Research Institute in conjunction with the Georgia Department of Transportation has proved in...

  1. Recycled tires as coarse aggregate in concrete pavement mixtures.

    Science.gov (United States)

    2013-07-01

    The reuse potential of tire chips as coarse aggregates in pavement concrete was examined in this research by : investigating the effects of low- and high-volume tire chips on fresh and hardened concrete properties. One concrete : control mixture was ...

  2. Iowa pavement asset management decision-making framework.

    Science.gov (United States)

    2015-10-01

    Most local agencies in Iowa currently make their pavement treatment decisions based on their limited experience due primarily to : lack of a systematic decision-making framework and a decision-aid tool. The lack of objective condition assessment data...

  3. Evaluation of acceptance strength tests for concrete pavements.

    Science.gov (United States)

    2005-06-30

    The North Carolina Department of Transportation has used traditionally flexural strength tests for acceptance : testing of Portland cement concrete pavements. This report summarizes a research project implemented to : investigate the feasibility of u...

  4. Airport Pavement Design For The Boeing 777 Airplane

    Science.gov (United States)

    1995-10-22

    The purpose of this advisory circular is to provide thickness design standards : for pavements intended to serve the Boeing 777 airplane. A new method of design : based on layered elastic analysis has been developed to calculate design : thickness fo...

  5. Rehabilitation design of flexible pavements in South Africa.

    CSIR Research Space (South Africa)

    De Beer

    1997-01-01

    Full Text Available This report contains a set of practical course notes on the Rehabilitation Design of flexible pavements in southern Africa based on extensive research by various researchers and / or practitioners in South Africa. The course is intended...

  6. Pavement subgrade MR design values for Michigan's seasonal changes : appendices.

    Science.gov (United States)

    2009-07-22

    The resilient modulus (MR) of roadbed soil plays an integral role in the design of pavement systems. Currently, the various regions of the Michigan Department of Transportation (MDOT) use different procedures to determine the MR values. Most of these...

  7. Investigation clogging dynamic of permeable pavement systems using embeded sensors

    Data.gov (United States)

    U.S. Environmental Protection Agency — Permeable pavement is a stormwater control measure commonly selected in both new and retrofit applications. However, there is limited information about the clogging...

  8. Metal concentrations from permeable pavement parking lot in Edison, NJ

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency constructed a 4000-m2 parking lot in Edison, New Jersey in 2009. The parking lot is surfaced with three permeable pavements...

  9. Investigation of temperature correction for tire/pavement noise measurements

    Science.gov (United States)

    2010-11-01

    The Volpe Center Acoustics Facility, in support of the Federal Highway Administration, : investigated the influence of temperature on tire/pavement noise in order to provide guidance on correcting for temperature variations in measured sound levels. ...

  10. Deicer usage on concrete and asphalt pavements in Utah.

    Science.gov (United States)

    2014-06-01

    The objectives of this research were to 1) compile winter maintenance data for the Utah Department of : Transportation (UDOT) to directly compare concrete and asphalt pavements with regards to deicer usage and 2) : determine if there is a statistical...

  11. Life cycle and economic efficiency analysis: durable pavement markings.

    Science.gov (United States)

    2009-07-01

    This project examined the life cycle and economic efficiency of two pavement marking : materials inlaid tape and thermoplastic to find the most economical product for specific : traffic and weather conditions. Six locations in the state of Ma...

  12. Sustainable Mitigation of Stormwater Runoff Through Fully Permeable Pavement

    Science.gov (United States)

    2018-03-01

    This report presents the implementation of new design method developed using mechanistic-empirical design approach by University of California Pavement Research Center (UCPRC) through building two test sections at California State University Long Bea...

  13. Safety performance evaluation of converging chevron pavement markings : final report.

    Science.gov (United States)

    2014-12-01

    The objectives of this study were (1) to perform a detailed safety analysis of converging chevron : pavement markings, quantifying the potential safety benefits and developing an understanding of the : incident types addressed by the treatment, and (...

  14. Project Level Performance Database for Rigid Pavements in Texas, II

    Science.gov (United States)

    2011-08-01

    Over the years, the Texas Department of Transportation (TxDOT) has built a number of CRCP (continuously reinforced : concrete pavement) experimental sections to investigate the effects of design, materials, and construction variables on CRCP : struct...

  15. Inverted base pavements : new field test and design catalogue.

    Science.gov (United States)

    2014-01-01

    The current economic situation has severely affected the US road infrastructure and funding has become : inadequate for either maintenance or future growth. : The inverted base pavement structure is a promising alternative to achieve high quality roa...

  16. ANALYSIS OF GROUP MAINTENANCE STRATEGY -ROAD PAVEMENT AND SEWERAGE PIPES-

    Science.gov (United States)

    Tanimoto, Keishi; Sugimoto, Yasuaki; Miyamoto, Shinya; Nada, Hideki; Hosoi, Yoshihiko

    Recently, it is critical to manage deteriorating sewerage and road facilities efficiently and strategically. Since the sewerage pipes are mostly installed under road pavement, the works for the replacement of the sewerage pipes are partially common to the works for the road. This means that the replacement cost can be saved by coordinating the timing of the replacements by sewerage pipe and road pavement. The purpose of the study is to develop the model based on Markov decision process to derive the optimal group maintenance policy so as to minimize lifecycle cost. Then the model is applied to case study area and demonstrated to estimate the lifecycle cost using statistical data such as pipe replacement cost, road pavement rehabilitation cost, and state of deterioration of pipes and road pavement.

  17. Benefit cost models to support pavement management decisions.

    Science.gov (United States)

    2012-06-01

    A critical role of pavement management is to provide decision makers with estimates of the required budget level to achieve specific steady-state network conditions, and to recommend the best allocation of available budget among competing needs for m...

  18. Bleeding stomal varices in portal hypertension

    Directory of Open Access Journals (Sweden)

    Karen Tran-Harding, MD

    2018-04-01

    Full Text Available We report a case of a 50-year-old man with a history of liver cirrhosis and colon cancer post end colostomy presenting to the emergency department with stomal bleeding and passage of clots into the colostomy bag. The patient was treated with transjugular intrahepatic portosystemic shunt (TIPS and concomitant embolization of the stomal varices via the TIPS shunt using N-butyl cyanoacrylate mixed with ethiodol. Although stomal variceal bleeding is uncommon, this entity can have up to 40% mortality upon initial presentation, given the challenges in diagnosis and management. Currently, there are no established standard treatments for stomal variceal bleeding. In addition, to the best of our knowledge, there are no cases in the current literature in which treatment of this entity is performed with a combination of TIPS shunt placement and N-butyl cyanoacrylate variceal embolization. Keywords: Stomal varices, TIPS, Cirrhosis, Colon cancer, Embolization, NBCA

  19. Radiotherapy in benign uterine bleeding disorders

    International Nuclear Information System (INIS)

    Ryberg, M.; Pettersson, F.; Lundell, M.

    1989-01-01

    Radiotherapy was earlier a method of choice for treatment of benign bleeding disorders (metropathia), especially in woman of high surgical risk. During the period 1912 to 1977 933 women with benign bleeding disorders were treated at Radiumhemmet with intracavitary brachytherapy or external irradiation or a combination of both. The result with regard to cure of the uterine bleedings was good (48%). Hormonal withdrawal symptoms after treatment were noted in 45% of the patients. In the long term follow up an increased risk of cardiovascular death was found in women treated before menopause. Malignant tumours occurred in 107 cases versus 90.2 expected. The estimated ovarian dose of ionizing radiation varied from 3.5 Gy to 6.0 Gy for the three standard techniques. Two women gave birth to a healthy child 4 and 5 years after intracavitary radium treatment. The estimated absorbed dose to the ovaries in these two women were 1 Gy and 4 Gy, respectively

  20. Somatostatin analogues for acute bleeding oesophageal varices

    DEFF Research Database (Denmark)

    Gøtzsche, Peter C.; Hrobjartsson, A.

    2008-01-01

    BACKGROUND: Somatostatin and its derivatives are sometimes used for emergency treatment of bleeding oesophageal varices in patients with cirrhosis of the liver. OBJECTIVES: To study whether somatostatin or its analogues improve survival or reduce the need for blood transfusions in patients...... with bleeding oesophageal varices. SEARCH STRATEGY: PubMed and The Cochrane Library were searched (November 2007). Reference lists of publications, contacts with authors. SELECTION CRITERIA: All randomised trials comparing somatostatin or analogues with placebo or no treatment in patients suspected of acute...... or recent bleeding from oesophageal varices. DATA COLLECTION AND ANALYSIS: The outcome measures extracted were: mortality, blood transfusions, use of balloon tamponade, initial haemostasis and rebleeding. Intention-to-treat analyses including all randomised patients were conducted if possible; a random...

  1. Hemospray application in nonvariceal upper gastrointestinal bleeding

    DEFF Research Database (Denmark)

    Smith, Lyn A; Stanley, Adrian J; Bergman, Jacques J

    2013-01-01

    in combination with other hemostatic modalities at the endoscopists' discretion. RESULTS: Sixty-three patients (44 men, 19 women), median age 69 (range, 21 to 98) years with NVUGIB requiring endoscopic hemostasis were treated with TC-325. There were 30 patients with bleeding ulcers and 33 with other NVUGIB......BACKGROUND: Hemospray TM (TC-325) is a novel hemostatic agent licensed for use in nonvariceal upper gastrointestinal bleeding (NVUGIB) in Europe. GOALS: We present the operating characteristics and performance of TC-325 in the largest registry to date of patients presenting with NVUGIB in everyday...... pathology. Fifty-five (87%) were treated with TC-325 as monotherapy; 47 [85%; 95% confidence interval (CI), 76%-94%] of them achieved primary hemostasis, and rebleeding rate at 7 days was 15% (95% CI, 5%-25%). Primary hemostasis rate for TC-325 in patients with ulcer bleeds was 76% (95% CI, 59%-93%). Eight...

  2. Application of surplus and waste materials in roads pavement making

    OpenAIRE

    Mousavi, S. M.; Fazli, A. H.; Rouzmehr, F.

    2011-01-01

    Nowadays there are a lot of problems about surpluses and debris made by humans all around the world. Lots of these surpluses seriously harm our natural environment. Reuse of this kind of materials in other processes like building constructions or pavement help our natural environment in every aspect. Asphalt concrete is the main part of pavements in most parts of the world with an increasing rate of production in need of more ways and roads. In this paper we will provide...

  3. Flood Mitigation by Permeable Pavements in Chinese Sponge City Construction

    OpenAIRE

    Maochuan Hu; Xingqi Zhang; Yim Ling Siu; Yu Li; Kenji Tanaka; Hong Yang; Youpeng Xu

    2018-01-01

    It is important to evaluate the effectiveness of permeable pavements on flood mitigation at different spatial scales for their effective application, for example, sponge city construction in China. This study evaluated the effectiveness of three types of permeable pavements (i.e., permeable asphalts (PA), permeable concretes (PC), and permeable interlocking concrete pavers (PICP)) on flood mitigation at a community scale in China using a hydrological model. In addition, the effects of cloggin...

  4. Automatic Pavement Crack Recognition Based on BP Neural Network

    OpenAIRE

    Li, Li; Sun, Lijun; Ning, Guobao; Tan, Shengguang

    2014-01-01

    A feasible pavement crack detection system plays an important role in evaluating the road condition and providing the necessary road maintenance. In this paper, a back propagation neural network (BPNN) is used to recognize pavement cracks from images. To improve the recognition accuracy of the BPNN, a complete framework of image processing is proposed including image preprocessing and crack information extraction. In this framework, the redundant image information is reduced as much as possib...

  5. Research of cost aspects of cement pavements construction

    Science.gov (United States)

    Bezuglyi, Artem; Illiash, Sergii; Tymoshchuk, Oleksandr

    2017-09-01

    The tendency to increasing traffic volume on public roads and to increased axle loads of vehicles makes the road scientists to develop scientifically justified methods for preserving the existing and developing the new transport network of Ukraine. One of the options for solving such issues is the construction of roads with rigid (cement concrete) pavement. However, any solution must be justified considering technical and economic components. This paper presents the results of the research of cost aspects of cement pavements construction.

  6. Evaluation of pavement skid resistance using high speed texture measurement

    Directory of Open Access Journals (Sweden)

    Jay N. Meegoda

    2015-12-01

    Full Text Available Skid resistance is an important parameter for highway designs, construction, management, maintenance and safety. The purpose of this manuscript is to propose the correlation between skid resistance, which is measured as skid resistance trailer, and mean profile depth (MPD or the macro surface texture, which is measured by vehicle mounted laser, so that highway agencies can predict the skid resistance of pavement without the use of expensive and time consuming skid resistance trailer, which also causes disruption of traffic in use. In this research skid numbers and MPD from 5 new asphalt pavements and 4 old asphalt pavements were collected using a locked wheel skid trailer and a vehicle mounted laser. Using the data collected, a correlation between the skid number (SN40R collected by locked wheel skid tester and the texture data or MPD collected by a vehicle mounted laser operating at highway speeds was developed. The proposed correlation for new pavements was positive for MPD values less than 0.75 mm to reach a peak SN40R value, then there was a negative correlation as the MPD increases until the MPD value was equal to 1.1 mm and beyond the MPD value of 1.1 mm to the maximum value of 1.4 mm, SN40R value remained almost constant. There were significant data scatter for the MPD value of 0.8 mm. To explain these results, water film thickness during the friction test was calculated and the critical MPD was defined. The effect of sealed water pool on the SN40R was discussed. The test result showed a similar trend for older asphalt pavements, but with lower SN40R values due to the polishing of pavement micro-texture by traffic. Hence, a reduction factor was proposed for older pavements based on cumulative traffic volume for the above correlation to predict the skid resistance of older pavements.

  7. Successful Management of Neobladder Variceal Bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Atwal, Dinesh; Chatterjee, Kshitij, E-mail: kchatterjee@uams.edu [University of Arkansas for Medical Sciences, Department of Internal Medicine, Residency Program: Slot 634 (United States); Osborne, Scott [University of Arkansas for Medical Sciences, Division of Interventional Radiology, Department of Radiology (United States); Kakkera, Krishna; Deas, Steven [University of Arkansas for Medical Sciences, Department of Internal Medicine, Residency Program: Slot 634 (United States); Li, Ruizong [University of Arkansas for Medical Sciences, Division of Interventional Radiology, Department of Radiology (United States); Erbland, Marcia [University of Arkansas for Medical Sciences, Department of Internal Medicine, Residency Program: Slot 634 (United States)

    2016-10-15

    Hematuria from a neobladder can occur due to a variety of pathologies including tumors, stones, and fistulas. Variceal bleeding in a neobladder is a very rare condition with only one case reported in literature. We present a case of a patient with cirrhosis and portal hypertension and an ileocolic orthotopic neobladder presenting with hematuria. Computed tomographic angiography showed dilated varices around the neobladder which were successfully embolized. To the best of our knowledge, this is the first report case of variceal bleeding in a neobladder successfully managed with the combination of TIPS (transjugular intrahepatic portosystemic shunt) procedure and embolization.

  8. Endovascular management of acute bleeding arterioenteric fistulas

    DEFF Research Database (Denmark)

    Leonhardt, H.; Mellander, S.; Snygg, J.

    2008-01-01

    . All had massive persistent bleeding with hypotension despite volume substitution and transfusion by the time of endovascular management. Outcome after treatment of these patients was investigated for major procedure-related complications, recurrence, reintervention, morbidity, and mortality. Mean...... follow-up time was 3 months (range, 1-6 months). All massive bleeding was controlled by occlusive balloon catheters. Four fistulas were successfully sealed with stent-grafts, resulting in a technical success rate of 80%. One patient was circulatory stabilized by endovascular management but needed...

  9. Endovascular management of acute bleeding arterioenteric fistulas

    DEFF Research Database (Denmark)

    Leonhardt, H.; Mellander, S.; Snygg, J.

    2008-01-01

    follow-up time was 3 months (range, 1-6 months). All massive bleeding was controlled by occlusive balloon catheters. Four fistulas were successfully sealed with stent-grafts, resulting in a technical success rate of 80%. One patient was circulatory stabilized by endovascular management but needed...... reintervention. The in-hospital mortality was 20% and the 30-day mortality was 40%. The midterm outcome was poor, due to comorbidities or rebleeding, with a mortality of 80% within 6 months. In conclusion, endovascular repair is an efficient and safe method to stabilize patients with life-threatening bleeding...

  10. Pavement Response to Variable Tyre Pressure of Heavy Vehicles

    Directory of Open Access Journals (Sweden)

    Arshad Ahmad Kamil

    2016-01-01

    Full Text Available In recent years, the effect of overinflated tyre pressure and increased heavy vehicles’ axle load on flexible pavements has become a subject of great concern because of the higher stress levels induced and damage caused to road pavements. This paper aims to evaluate the effect of variable tyre inflation pressures (using actual tyre contact/footprint area to determine the responses of flexible pavement. A full scale experiment was conducted on a heavy vehicle with 1:1:2 axle configuration, 10 R 20 tyre size and attached trailer with constant axle load. Measurements were made for actual tyre-pavement contact area. KENPAVE linear elastic program was then used to analyse the effects of the measured actual tyre-pavement contact area and the results was compared using conventional circular tyre contact area. A comparative analysis was then made between the actual contact area and the conventional circular tyre contact area. It was found that high tyre inflation pressure produce smaller contact area, giving more detrimental effect on the flexible pavement. It was also found that the temperature of tyres when the heavy vehicles are operational give less significant impact on tyre inflation pressure for the Malaysian climate.

  11. Effect of speed hump characteristics on pavement condition

    Directory of Open Access Journals (Sweden)

    Talaat Ali Abdel-Wahed

    2017-02-01

    Full Text Available Speed humps are the most common type of traffic calming devices due to their low cost and easy installation. However, in many Egyptian roads, considerable number of these humps is randomly placed without proper engineering studies and justifications. Deterioration of pavement condition is observed near these humps. This paper presents a case study applied to collect and analyze visual inspection data for the reason of evaluating the impact of speed humps on pavement condition on intercity rural roads. The paper used 52 speed humps located in an intercity two-lane, two-way road that connects two cities, Tahta and Gerga, in Upper Egypt. The total length of this road is about 34 km. Pavement condition index (PCI, in road sections, near speed humps in the two directions of travel were calculated from the visual inspection measurements. The characteristics of each speed hump (width, height, and distance from preceding hump were measured. Using statistical analyses, the correlations between the pavement conditions and hump characteristics were examined. Regression analysis models were developed to represent the relationships between pavement conditions and hump characteristics. Generally, the results proved that the pavement conditions are greatly influenced by the presence of speed humps and hump characteristics.

  12. Noise emission of concrete pavement surfaces produced by diamond grinding

    Directory of Open Access Journals (Sweden)

    Jens Skarabis

    2015-04-01

    Full Text Available In Germany, diamond grinding is frequently used to improve the evenness and skid resistance of concrete pavement surfaces. Since diamond grinding has been observed to affect tyre/pavement noise emission favourably, the relationship among surface texture, concrete composition and noise emission of concrete pavement surfaces has been systematically investigated. The simulation program SPERoN was used in a parameter study to investigate the main factors which affect noise emission. Based on the results of the simulations, textured concrete surfaces were produced by using a laboratory grinding machine. As well as the composition of the concrete, the thickness and spacing of the diamond blades were varied. The ability of the textured surfaces to reduce noise emission was assessed from the texture characteristics and air flow resistance of textured surfaces measured in the laboratory. It was found that concrete composition and, in particular, the spacing of the blades affected the reduction in noise emission considerably. The noise emission behaviour of numerous road sections was also considered in field investigations. The pavement surfaces had been textured by diamond grinding during the last years or decades. The results show that diamond grinding is able to provide good, durable noise-reducing properties. Several new pavement sections were investigated using thicknesses and spacings of the blades similar to those used in the laboratory to optimize noise emission reduction. It is concluded that diamond grinding is a good alternative to exposed aggregate concrete for the production of low-noise pavement surfaces.

  13. Influence of pavement condition on horizontal curve safety.

    Science.gov (United States)

    Buddhavarapu, Prasad; Banerjee, Ambarish; Prozzi, Jorge A

    2013-03-01

    Crash statistics suggest that horizontal curves are the most vulnerable sites for crash occurrence. These crashes are often severe and many involve at least some level of injury due to the nature of the collisions. Ensuring the desired pavement surface condition is one potentially effective strategy to reduce the occurrence of severe accidents on horizontal curves. This study sought to develop crash injury severity models by integrating crash and pavement surface condition databases. It focuses on developing a causal relationship between pavement condition indices and severity level of crashes occurring on two-lane horizontal curves in Texas. In addition, it examines the suitability of the existing Skid Index for safety maintenance of two-lane curves. Significant correlation is evident between pavement condition and crash injury severity on two-lane undivided horizontal curves in Texas. Probability of a crash becoming fatal is appreciably sensitive to certain pavement indices. Data suggested that road facilities providing a smoother and more comfortable ride are vulnerable to severe crashes on horizontal curves. In addition, the study found that longitudinal skid measurement barely correlates with injury severity of crashes occurring on curved portions. The study recommends exploring the option of incorporating lateral friction measurement into Pavement Management System (PMS) databases specifically at curved road segments. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Feasibility of perpetual pavement stage construction in China: A life cycle cost analysis

    Directory of Open Access Journals (Sweden)

    Zhongyin Guo

    2016-12-01

    Full Text Available The main objective of pavement design and management is to build sustainable pavement structure with minimum costs during its whole life. There are many uncertainties in the process of pavement design pertaining many of its variables, such as future traffic estimation, long time behavior of materials, future weights and types of traveling vehicles, availability of funds etc. Therefore, it is important to apply pavement stage construction technique during the process of pavement design and management to minimize the risk associated with these uncertainties. From the beginning of 2000, the research and application of perpetual asphalt pavement (PP technology has been deployed in China. The semi rigid base for asphalt pavement has been normally considered as typical component of high class highways in the design according to the Chinese experience since 1997. The research objective is to apply pavement stage construction for the evaluation of life cycle costs of Chinese perpetual and traditional semi rigid pavements using operational pavement management system in addition to examine its suitability for design and construction of more economical and durable flexible pavements. It has been found that the stage construction of asphalt layers in PP over semi rigid pavement foundation will create more sustainable and trusted pavement structures in spite of 2–5% increase in present total cost.

  15. Improve the quality and service life of water-based pavement marking paints on pavements with high-iron aggregates.

    Science.gov (United States)

    2015-08-01

    White pavement paint marking on airport runways was being discolored by rust-like staining. Discoloration is a critical safety : problem because white paint indicates runways and yellow paint is used for taxiways and aircraft parking. When the white ...

  16. 0-6683 : develop a pavement project evaluation index to support the 4-year pavement management plan.

    Science.gov (United States)

    2013-08-01

    A pavement management plan (PMP) identifies : candidate maintenance and rehabilitation (M&R) : projects for a particular roadway network over a : multi-year planning period. The PMP is a living : document because projects are reevaluated and : reprio...

  17. Evaluation and Development of Pavement Scores, Performance Models and Needs Estimates for the TXDOT Pavement Management Information System : Final Report

    Science.gov (United States)

    2012-10-01

    This project conducted a thorough review of the existing Pavement Management Information System (PMIS) database, : performance models, needs estimates, utility curves, and scores calculations, as well as a review of District practices : concerning th...

  18. Scintigraphic pattern of small bowel bleeding

    International Nuclear Information System (INIS)

    Anshu Rajnish Sharma; Charan, S.; Silva, I.

    2004-01-01

    Introduction: Small intestine is the longest part of gastrointestinal tract. Intra-luminal haemorrhage occurring anywhere in its long and tortuous course is difficult to trace. It is relatively inaccessible to endoscopic evaluation. Upper GI endoscopy can see only up to distal duodenum, whereas colonoscope can view maximum of 30 centimeters of terminal ileum after negotiating the scope through ileo-caecal valve. Hence, localization of bleeding source from small bowel remains a difficult clinical problem. This group of patients can be evaluated with scintigraphy for localizing the site of bleeding before undergoing either angiography or surgery. To our best of knowledge, there is no study, which has utilized scintigraphy for evaluation of small bowel bleed exclusively. The present study has been designed to know the efficacy of 99mTc-RBC scintigraphy in detecting small bowel bleed and to know whether it can differentiate between jejunal and ileal bleeding ? Materials and methods: Thirteen patients presenting with lower gastrointestinal bleeding (malena) were enrolled for the study. In all cases, upper GI endoscopy (UGIE) was unremarkable. Colonoscopic examination was either negative or suspected bleeding occurring proximal to ileo-caecal valve. Thus, in these patients, it is presumed clinically that bleeding is originating from small bowel. Barium meal follow through (BMFT) studies, however, could not delineate any etiological lesion in these patients. There were 8 men and 5 women (mean age 48 years). All patients were anemic (Hb- 6 gm%) and mean 3 units of blood were transfused.These patients were subjected to Tc-99m labeled red blood cells scintigraphy (15 mci, in-vivo method) for localization of source of bleeding. The scintiscan was acquired in two phases. A first pass phase acquired at a rate of 2 seconds per frame for 60 seconds followed by acquisition of static abdominal images (500 K, 256 x 256 matrix) at 5 minutes intervals up to 90 minutes on LFOV gamma

  19. Prospective analysis of delayed colorectal post-polypectomy bleeding.

    Science.gov (United States)

    Park, Soo-Kyung; Seo, Jeong Yeon; Lee, Min-Gu; Yang, Hyo-Joon; Jung, Yoon Suk; Choi, Kyu Yong; Kim, Hungdai; Kim, Hyung Ook; Jung, Kyung Uk; Chun, Ho-Kyung; Park, Dong Il

    2018-01-17

    Although post-polypectomy bleeding is the most frequent complication after colonoscopic polypectomy, only few studies have investigated the incidence of bleeding prospectively. The aim of this study was to investigate the incidence of delayed post-polypectomy bleeding and its associated risk factors prospectively. Patients who underwent colonoscopic polypectomy at Kangbuk Samsung Hospital from January 2013 to December 2014 were prospectively enrolled in this study. Trained nurses contacted patients via telephone 7 and 30 days after polypectomy and completed a standardized questionnaire regarding the development of bleeding. Delayed post-polypectomy bleeding was categorized as minor or major and early or late bleeding. Major delayed bleeding was defined as a > 2-g/dL drop in the hemoglobin level, requiring hospitalization for control of bleeding or blood transfusion; late delayed bleeding was defined as bleeding occurring later than 24 h after polypectomy. A total of 8175 colonoscopic polypectomies were performed in 3887 patients. Overall, 133 (3.4%) patients developed delayed post-polypectomy bleeding. Among them, 90 (2.3%) and 43 (1.1%) patients developed minor and major delayed bleeding, respectively, and 39 (1.0%) patients developed late delayed bleeding. In the polyp-based multivariate analysis, young age ( 10 mm (OR 2.45; 95% CI 1.38-4.36) were significant risk factors for major delayed bleeding, while young age (< 50 years; OR 2.6; 95% CI 1.35-5.12) and immediate bleeding (OR 3.3; 95% CI 1.49-7.30) were significant risk factors for late delayed bleeding. Young age, aspirin use, polyp size, and immediate bleeding were found to be independent risk factors for delayed post-polypectomy bleeding.

  20. The Multifactorial Nature of Thromboembolic and Bleeding ...

    African Journals Online (AJOL)

    Background: Thromboembolic and bleeding complications are the main causes of morbidity and mortality in patients with mechanical heart valves1. The risk factors for these complications in Tanzania have not been established. Methods: A retrospective cohort study was conducted among patients with mechanical heart ...

  1. Dysfunctional uterine bleedings of a climacteric period

    International Nuclear Information System (INIS)

    Prilepskaya, V.N.

    1993-01-01

    Climacteric period of some women is complicated by dysfunctional uterine bleedings (DUB). Bearing in mind the fact that DUBS are caused by disorder of estrin rhysmic secretion, the paper presents the methods of differential diagnostics for investigations into functional disorders in the hypothalamus -hypophysis - ovaries - uterus system. The preference is given to roentgenologic and radioimmunologic diagnostic methods

  2. Systemic causes of heavy menstrual bleeding

    NARCIS (Netherlands)

    Verschueren, Sophie

    2017-01-01

    Heavy menstrual bleeding (HMB) is a common problem in fertile women. In addition to local factors, such as a polyp or a uterine fibroid, systemic causes may lead to HMB. These systemic causes are discussed in this thesis. For years, women with HMB were tested underlying thyroid disorder, but our

  3. Thromboembolic and Bleeding Complications among Patients with ...

    African Journals Online (AJOL)

    Objective: This study was conducted to determine the incidence of thromboembolic and bleeding complications among patients with mechanical heart valves operated from 1990 to 2003 attending the Muhimbili National Hospital. Study design: This was a retrospective cohort study conducted at the cardiac, anticoagulation ...

  4. RESEARCH Endoscopic injection sclerotherapy for bleeding varices ...

    African Journals Online (AJOL)

    RESEARCH. 884 November 2012, Vol. 102, No. 11 SAMJ. Endoscopic injection sclerotherapy for bleeding varices in children with intrahepatic and extrahepatic portal venous ... Progress has been made in developing newer endoscopic techniques ... a sclerosant, usually 0.5 - 0.75 ml per injection, at multiple (up to.

  5. Massive rectal bleeding from colonic diverticulosis

    African Journals Online (AJOL)

    ABEOLUGBENGAS

    barium enema studies have indicated increasing world prevalence ... Other diagnostic modalities include barium enema, computerised ... This is in contrast to the findings in our patient when colonoscopy was carried out, in which the diverticula were more at the descending colon-left sided, and were found to be bleeding.

  6. An unusual cause of lower gastrointestinal bleeding: ' '

    African Journals Online (AJOL)

    Summary. This is an unusual case report of a 60-year-old man who presented with massive rectal bleeding due to angiomatous formation. ' He was also found to be cirrhosis and to have an ectopic left kidney in the ... attribuable a la formation angiomateuse. On a decouvert qu' ... challenging experience to the treating team.

  7. Management of Acute Bleeding Per Rectum

    Directory of Open Access Journals (Sweden)

    Benita K.T. Tan

    2004-01-01

    Conclusion: Perianal conditions contributed to the majority of acute patient admissions. Colonic causes of bleeding were less common and were most stable. There were differences in the frequencies of aetiologies in our population compared to Western populations. Understanding the common pathologies and outcomes guides the management of our patients.

  8. Endometrial biopsy findings in postmenopausal bleeding

    International Nuclear Information System (INIS)

    Sarfraz, T.; Tariq, H.

    2007-01-01

    To study endometrial histopathology in women presenting with postmenopausal bleeding. A two-year study from January 2003 to December 2004 of 100 cases of postmenopausal bleeding was conducted at Combined Military Hospital, Sialkot. The histopathology of endometrial biopsy specimens was done to find out the causes of postmenopausal bleeding in these ladies. All these 100 patients had confirmed menopause and the average age was 55 years and above. The most common histopathological diagnosis was senile endometrial atrophy (27%), followed by simple cystic hyperplasia in (17%). Three cases of simple cystic hyperplasia had coexistent ovarian tumors. Glandular hyperplasia without atypia was seen in 6% and with atypia in 4%. Other causes were endometritis (13%), endometrial polyps (8%), proliferative phase endometrium (6%) and secretary phase endometrium (5%). Endometrial carcinoma was seen in (6%) cases, (8%) biopsy specimens were non-representative. Although senile endometrial atrophy was most commonly found in these ladies but a significant percentage of endometrial hyperplasia and endometrial cancer implies the need for investigating all cases of postmenopausal bleeding. Bimanual examination and pelvic ultrasonography should be combined with endometrial sampling so that rare pelvic pathologies may not be missed. (author)

  9. Continued bleeding following acute intracerebral hemorrhage

    NARCIS (Netherlands)

    Brouwers, H.B.

    2014-01-01

    In this Ph.D. thesis, ‘Continued bleeding following acute intracerebral hemorrhage’, we have discussed the background literature, risk factors, and underlying biology of hematoma expansion, as well as the clinical applicability of the CT angiography (CTA) 'spot sign' as an imaging marker of this

  10. First trimester bleeding and maternal cardiovascular morbidity

    DEFF Research Database (Denmark)

    Lykke, Jacob A; Langhoff-Roos, Jens

    2012-01-01

    First trimester bleeding without miscarriage is a risk factor for complications later in the pregnancy, such as preterm delivery. Also, first trimester miscarriage has been linked to subsequent maternal ischemic heart disease. We investigated the link between maternal cardiovascular disease prior...

  11. Managing Chemotherapy Side Effects: Bleeding Problems

    Science.gov (United States)

    ... nurse: 1. What problems should I call you about? 2. How long should I wait for the bleeding to stop before I call you or go to the emergency room? 3. Is it okay to drink beer, wine, or other drinks with alcohol? Yes No, don’ ...

  12. Medical treatment for heavy menstrual bleeding

    Directory of Open Access Journals (Sweden)

    Yi-Jen Chen

    2015-10-01

    Full Text Available Heavy menstrual bleeding, or menorrhagia, is subjectively defined as a “complaint of a large amount of bleeding during menstrual cycles that occurs over several consecutive cycles” and is objectively defined as menstrual blood loss of more than 80 mL per cycle that is associated with an anemia status (defined as a hemoglobin level of <10 g/dL. During their reproductive age, more than 30% of women will complain of or experience a heavy amount of bleeding, which leads to a debilitating health outcome, including significantly reduced health-related quality of life, and a considerable economic burden on the health care system. Although surgical treatment might be the most important definite treatment, especially hysterectomy for those women who have finished bearing children, the uterus is still regarded as the regulator and controller of important physiological functions, a sexual organ, a source of energy and vitality, and a maintainer of youth and attractiveness. This has resulted in a modern trend in which women may reconsider the possibility of organ preservation. For women who wish to retain the uterus, medical treatment may be one of the best alternatives. In this review, recent trends in the management of women with heavy menstrual bleeding are discussed.

  13. Modeling of interaction between steel and concrete in continuously reinforced concrete pavements : final report.

    Science.gov (United States)

    2016-01-01

    Continuously reinforced concrete pavement (CRCP) contains continuous longitudinal reinforcement with no transverse : expansion within the early life of the pavement and can continue to develop cracks in the long-term. The : accurate modeling of CRCPs...

  14. Typical and darkened Portland cement concrete pavement: temperature, moisture, and roughness analyses : final report.

    Science.gov (United States)

    2017-01-01

    The objectives of this research were to 1) investigate the effects of lower concrete albedo on the thermal behavior of concrete pavement by directly comparing temperatures and moisture contents of typical and darkened concrete pavements and 2) invest...

  15. Update to Permeable Pavement Research at the Edison Environmental Center - proceedings

    Science.gov (United States)

    The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavements including interlocking concrete permeable pavers, p...

  16. Update to Permeable Pavement Research at the Edison Environmental Center - abstract

    Science.gov (United States)

    Abstract The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavement including: interlocking concrete permeable pavers...

  17. Update to permeable pavement research at the Edison Environmental Center - slides

    Science.gov (United States)

    Abstract: The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavement including: interlocking concrete permeable paver...

  18. Evaluating the Effect of Slab Curling on IRI for South Carolina Concrete Pavements

    Science.gov (United States)

    2010-10-01

    Concrete pavements are known to curl due to a temperature gradient within the concrete caused by both daily : and seasonal temperature variations. This research project measured the magnitude of concrete pavement slab : curling of two newly construct...

  19. Engineering properties of stabilized subgrade soils for implementation of the AASHTO 2002 pavement design guide.

    Science.gov (United States)

    2009-06-01

    A comprehensive laboratory study was undertaken to determine engineering properties of cementitiously stabilized common subgrade soils in Oklahoma for the design of roadway pavements in accordance with the AASHTO 2002 Mechanistic-Empirical Pavement D...

  20. Standard nomenclature and methods for describing the condition of pavements draft TRH 6

    CSIR Research Space (South Africa)

    Curtayne, PC

    2009-01-26

    Full Text Available The need for describing the condition of pavements occurs frequently in highway engineering. Accurate descriptions are a prerequisite for establishing procedures with which to evaluate the various aspects of the pavement condition. A variety...

  1. Effectiveness of noise barriers installed adjacent to transverse grooved concrete pavement.

    Science.gov (United States)

    2009-10-16

    In recent years the Ohio Department of Transportation (ODOT) has reconstructed a number of roadways where asphalt pavements were replaced with random transverse grooved concrete pavements. Upon completion, residents living adjacent to the reconstruct...

  2. Evaluation of concrete pavements with materials-related distress : appendix G.

    Science.gov (United States)

    2010-03-02

    An evaluation of cores sampled from six concrete pavements was performed. Factors contributing to pavement distress observed in the field were determined, including expansive alkali-silica reactivity and freeze-thaw deterioration related to poor entr...

  3. Best practices and performance assessment for preventive maintenance treatments for Virginia pavements.

    Science.gov (United States)

    2015-08-01

    Preventive maintenance has the potential to improve network condition by retarding future pavement deterioration. This : report outlines guidelines for implementing a preventive maintenance policy for bituminous pavements. : Preventive maintenance tr...

  4. Long-term pavement performance program manual for profile measurements and processing

    Science.gov (United States)

    2008-11-01

    This manual describes operational procedures for measuring longitudinal pavement profiles for the Long-Term Pavement Performance (LTPP) Program using the International Cybernetics Corporation (ICC) road profiler, Face Company Dipstick, and the rod an...

  5. Effect of drainage in unbound aggregate bases on flexible pavement performance.

    Science.gov (United States)

    2008-05-01

    It has been well demonstrated that a positive subsurface drainage is beneficial in enhancing pavement performance and thus extending pavement service life. Typical permeable base materials include asphalt/cement-treated, open-graded aggregates and un...

  6. Mechanistic-empirical design concepts for continuously reinforced concrete pavements in Illinois.

    Science.gov (United States)

    2009-04-01

    The Illinois Department of Transportation (IDOT) currently has an existing jointed plain concrete pavement : (JPCP) design based on mechanistic-empirical (M-E) principles. However, their continuously reinforced concrete : pavement (CRCP) design proce...

  7. Evaluating the effects of concrete pavement curling and warping on ride quality.

    Science.gov (United States)

    2015-09-01

    Construction of a jointed concrete pavement on US 34 near Greeley, Colorado in 2012 led to an investigation of slab curling : and warping that appeared to be contributing to undesirable levels of pavement roughness. Specifically, the westbound lanes ...

  8. Winter tenting of highway pavements : test program and discussion of causes and mechanisms

    Science.gov (United States)

    2000-10-28

    Tenting consists of localized frost heaving in the immediate vicinity of transverse pavement cracks. It produces a highly irregular riding : surface, leads to premature pavement-surface deterioration, occurs on highways designed for high traffic volu...

  9. Recycled Portland cement concrete pavements : Part II, state-of-the art summary.

    Science.gov (United States)

    1979-01-01

    This report constitutes a review of the literature concerning recycling of portland cement concrete pavements by crushing the old pavement and reusing the crushed material as aggregate in a number of applications. A summary of the major projects cond...

  10. Long-term infiltration capacity of different types of permeable pavements.

    Science.gov (United States)

    2017-08-01

    Permeable pavements such as porous asphalt, pervious concrete and permeable interlocking concrete pavers are relatively novel alternatives to conventional pavement that allow rain and snowmelt to infiltrate, thereby reducing runoff, flooding and nonp...

  11. Determination of coefficient of thermal expansion effects on Louisiana's PCC pavement design : technical summary report.

    Science.gov (United States)

    2011-12-01

    The coefficient of thermal expansion (CTE) has been widely considered as a fundamental property of : Portland cement concrete (PCC) pavement but has never played an important role in the thickness design : procedure for PCC pavement until recently. I...

  12. Implementation of Rolling Wheel Deflectometer (RWD) in PMS and Pavement Preservation : Tech Summary

    Science.gov (United States)

    2012-08-01

    Evaluation of pavement structural capacity and integrity is an important component of the Pavement Management : System (PMS) to assist in the selection of suitable maintenance and rehabilitation strategies. The falling weight : defl ectometer (FWD) i...

  13. MDOT innovation leading to faster, longer-lasting pavement repairs : research spotlight.

    Science.gov (United States)

    2015-01-01

    Current methods of patching pavement must evolve to meet increasing mobility demands. : To address this need, MDOT has been testing a new generation of rapid set full-depth : pavement repair materials. Initial results are promising. The new materials...

  14. Top-down cracking of rigid pavements constructed with fast setting hydraulic cement concrete

    CSIR Research Space (South Africa)

    Heath, AC

    2009-01-29

    Full Text Available Jointed plain concrete pavement (JPCP) test sections were constructed using fast setting hydrualic cement concrete (FSHCC) as part of the California accelerated pavement testing program (CAL/APT). Many of the longer slabs cracked under environmental...

  15. Long term validation of an accelerated polishing test procedure for HMA pavements.

    Science.gov (United States)

    2013-04-01

    The Ohio Department of Transportation (ODOT) has set strategic goals to improve driving safety by maintaining : smooth pavement surfaces with high skid resistance. ODOT has taken the initiative to monitor pavement : friction on Ohio roadways and reme...

  16. Transition from manual to automatic rutting measurements : effect on pavement serviceability index values.

    Science.gov (United States)

    2010-06-01

    The Pavement Serviceability Index (pSn is used by New Mexico Department of Transportation : (NMDOT) to express the serviceability level of a pavement section at the network level. The PSI : is calculated with distress ratings (including rutting) and ...

  17. Evaluation of concrete pavements with materials-related distress : appendix C.

    Science.gov (United States)

    2010-03-02

    An evaluation of cores sampled from six concrete pavements was performed. Factors contributing to pavement distress observed in the field were determined, including expansive alkali-silica reactivity and freeze-thaw deterioration related to poor entr...

  18. Texas flexible pavements and overlays : data analysis plans and reporting format.

    Science.gov (United States)

    2012-01-01

    This five-year project was initiated to collect materials and pavement performance data on a minimum of 100 : highway test sections around the State of Texas, incorporating flexible pavements and overlays. Besides being used to : calibrate and valida...

  19. Evaluation of concrete pavements with materials-related distress : appendix B.

    Science.gov (United States)

    2010-02-02

    An evaluation of cores sampled from six concrete pavements was performed. Factors contributing to pavement distress observed in the field were determined, including expansive alkali-silica reactivity and freeze-thaw deterioration related to poor entr...

  20. Using recycled concrete as aggregate in concrete pavements to reduce materials cost.

    Science.gov (United States)

    2013-08-01

    The main objective of this project was to evaluate the effects of using aggregate produced from crushed concrete pavement as a replacement for natural (virgin) coarse aggregate in pavement mixtures. A total of ten different concrete mixtures containi...

  1. Considerations for rigid vs. flexible pavement designs when allowed as alternate bids : technical report.

    Science.gov (United States)

    2009-08-01

    This report documents the research conducted for the Texas Department of Transportation (TxDOT) : concerning the use of pavement alternates. The scope of the project includes reviewing the state-of-thepractice : in methods used for pavement type sele...

  2. A methodology to support the development of 4-year pavement management plan.

    Science.gov (United States)

    2014-07-01

    A methodology for forming and prioritizing pavement maintenance and rehabilitation (M&R) projects was developed. : The Texas Department of Transportation (TxDOT) can use this methodology to generate defensible and cost-effective : 4-year pavement man...

  3. Alternate bidding strategies for asphalt and concrete pavement projects utilizing life cycle cost analysis (LCCA).

    Science.gov (United States)

    2012-07-01

    Recent changes in pavement materials costs have impacted the competitive environment relative to the : determination of the most cost effective pavement structure for a specific highway project. In response, State : highway agencies have renewed thei...

  4. Effect of Michigan multi-axle trucks on pavement distress and profile: volume 2.

    Science.gov (United States)

    2009-02-01

    With the adoption of the new mechanistic-empirical pavement design method and the employment of axle load spectra, the question of evaluating the pavement damage resulting from different axle and truck configurations has become more relevant. In part...

  5. Effect of Michigan multi-axle trucks on pavement distress and profile: volume 3.

    Science.gov (United States)

    2009-02-01

    With the adoption of the new mechanistic-empirical pavement design method and the employment of axle load : spectra, the question of evaluating the pavement damage resulting from different axle and truck configurations has : become more relevant. In ...

  6. Effect of Michigan multi-axle trucks on pavement distress and profile : volume 1.

    Science.gov (United States)

    2009-02-01

    With the adoption of the new mechanistic-empirical pavement design method and the employment of axle load : spectra, the question of evaluating the pavement damage resulting from different axle and truck configurations has : become more relevant. In ...

  7. Nondestructive pavement evaluation using finite element analysis based soft computing models.

    Science.gov (United States)

    2009-09-15

    Evaluating structural condition of existing, in-service pavements constitutes annually a major part of the : maintenance and rehabilitation activities undertaken by State Highway Agencies (SHAs). Accurate : estimation of pavement geometry and layer m...

  8. Texas flexible pavements and overlays : calibration plans for M-E models and related software.

    Science.gov (United States)

    2013-06-01

    This five-year project was initiated to collect materials and pavement performance data on a minimum of 100 highway test sections around the State of Texas, incorporating flexible pavements and overlays. Besides being used to calibrate and validate m...

  9. Effectiveness of noise barriers installed adjacent to transverse grooved concrete pavement : executive summary report.

    Science.gov (United States)

    2009-10-16

    In recent years the Ohio Department of Transportation (ODOT) has reconstructed a number of roadways where asphalt pavements were replaced with concrete pavements which were finished with a random transverse grooved surface texture (ODOT specification...

  10. Assessment of asphalt concrete reinforcement grid in flexible pavements : final report.

    Science.gov (United States)

    2016-05-01

    This report investigated the application of accepted methods of pavement structural evaluation to independently assess the potential structural benefit of asphalt geogrid reinforcement of an operational flexible highway pavement. The asphalt interlay...

  11. Evaluation of concrete pavements with materials-related distress : appendix E.

    Science.gov (United States)

    2010-03-02

    An evaluation of cores sampled from six concrete pavements was performed. Factors contributing to pavement distress observed in the field were determined, including expansive alkali-silica reactivity and freeze-thaw deterioration related to poor entr...

  12. Performance evaluation of Arizona's LTPP SPS-5 project : strategic study of rehabilitation of asphalt concrete pavements.

    Science.gov (United States)

    2015-06-01

    As part of the Long Term Pavement Performance (LTPP) Program, the Arizona Department of Transportation : (ADOT) constructed 11 Specific Pavement Study5 (SPS5) test sections on Interstate 8 near Casa Grande. The : SPS5 project studied a varie...

  13. Performance evaluation of Arizona's LTPP SPS-2 project : strategic study of structural factors for rigid pavements.

    Science.gov (United States)

    2015-10-01

    As part of the Long Term Pavement Performance (LTPP) Program, Arizona Department of Transportation : (ADOT) constructed 21 Specific Pavement Studies 2 (SPS-2) test sections on Interstate 10 near Buckeye, : Arizona, to study a variety of structural se...

  14. Simulation of dynamic traffic loading based on accelerated pavement testing (APT)

    CSIR Research Space (South Africa)

    Steyn, WJvdM

    2004-03-01

    Full Text Available The objective of this paper is to introduce the latest Heavy Vehicle Simulator (HVS) technology as part of the South African Accelerated Pavement Testing (APT) efforts, its capabilities and expected impact on road pavement analysis....

  15. Toward using tire-road contact stresses in pavement design and analysis

    CSIR Research Space (South Africa)

    De Beer, Morris

    2012-10-01

    Full Text Available Optimization of road pavement design, especially towards the surface of the pavement, requires a more rational approach to modeling of truck tire-road contact stresses. Various road surfacing failures are given in this paper as examples...

  16. Towards using tire-road contact stresses in pavement design and analysis

    CSIR Research Space (South Africa)

    De Beer, Morris

    2011-09-01

    Full Text Available Optimization of road pavement design, especially towards the surface of the pavement, requires a more rational approach to modeling of truck tire-road contact stresses. Various road surfacing failures are given in this paper as examples...

  17. Flexible and composite structures for premium pavements. Volume 2, Design manual

    Science.gov (United States)

    1980-11-01

    This design manual presents the results of a detailed study to identify and design flexible and composite pavement configurations which will perform as premium or "zero-maintenance" pavements. This manual includes identification and classification of...

  18. Risk Factors for Post-TAVI Bleeding According to the VARC-2 Bleeding Definition and Effect of the Bleeding on Short-Term Mortality: A Meta-analysis.

    Science.gov (United States)

    Wang, Jiayang; Yu, Wenyuan; Jin, Qi; Li, Yaqiong; Liu, Nan; Hou, Xiaotong; Yu, Yang

    2017-04-01

    In this study we investigated the effect of post-transcatheter aortic valve implantation (TAVI) bleeding (per Valve Academic Research Consortium-2 [VARC-2] bleeding criteria) on 30-day postoperative mortality and examined the correlation between pre- or intraoperative variables and bleeding. Multiple electronic literature databases were searched using predefined criteria, with bleeding defined per Valve Academic Research Consortium-2 criteria. A total of 10 eligible articles with 3602 patients were included in the meta-analysis. The meta-analysis revealed that post-TAVI bleeding was associated with a 323% increase in 30-day postoperative mortality (odds risk [OR]; 4.23, 95% confidence interval [CI], 2.80-6.40; P Risk Evaluation (EuroSCORE), aortic valve area, mean pressure gradient, left ventricular ejection fraction, preoperative hemoglobin and platelet levels, and study design had no significant effects on the results of the meta-analysis. Post-TAVI bleeding, in particular, major bleeding/life-threatening bleeding, increased 30-day postoperative mortality. Transapical access was a significant bleeding risk factor. Preexisting AF independently correlated with TAVI-associated bleeding, likely because of AF-related anticoagulation. Recognition of the importance and determinants of post-TAVI bleeding should lead to strategies to improve outcomes. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  19. THERMOELECTRIC SEMICONDUCTOR DEVICE FOR CAUTERY OF BLEEDING

    Directory of Open Access Journals (Sweden)

    Denis V. Yevdulov

    2017-01-01

    Full Text Available Abstract. Objectives The aim of the work is to study the possibilities for using a semiconductor device to cauterise bleeding by means of cooling (cryocautery. Method The study is based on methods for approximate modeling of heat exchange processes. Results The construction of a device for cauterisation of bleeding, the actuating element of which consists of a thermoelectric battery operating in cooling mode at the time of blood flow cautery and in heating mode when removing the device from the damaged area, is considered. A model of a device, realised on the basis of the solution of the problem of solidification of a viscous liquid by the method of L.S. Leibenson, is proposed, taking into account the electro- and thermo-physical characteristics of the thermoelectric battery cold source. As a result of the numerical experiment, the dependence of the duration of the ice crust formation on tissues 1 mm thick (which corresponds to the cauterisation of bleeding is obtained on the value of the supply current of the thermoelectric battery. With increasing current, the duration of the ice crust formation is reduced; this can be of the order of 160 s at 5 A. It was demonstrated that the selection of thermoelectric battery parameters and current should be guided by medical norms and standards in order to avoid frostbite in the tissues adjacent to the bleeding zone. Conclusion The special design of thermoelectric device provides an effective technical means for cauterising bleeding by freezing (cryocautery, providing high intensity of cooling, shortenened thrombus formation duration, and eliminating painful sensations when removing the device from a damaged area. 

  20. Endovascular Management of Acute Bleeding Arterioenteric Fistulas

    International Nuclear Information System (INIS)

    Leonhardt, Henrik; Mellander, Stefan; Snygg, Johan; Loenn, Lars

    2008-01-01

    The objective of this study was to review the outcome of endovascular transcatheter repair of emergent arterioenteric fistulas. Cases of abdominal arterioenteric fistulas (defined as a fistula between a major artery and the small intestine or colon, thus not the esophagus or stomach), diagnosed over the 3-year period between December 2002 and December 2005 at our institution, were retrospectively reviewed. Five patients with severe enteric bleeding underwent angiography and endovascular repair. Four presented primary arterioenteric fistulas, and one presented a secondary aortoenteric fistula. All had massive persistent bleeding with hypotension despite volume substitution and transfusion by the time of endovascular management. Outcome after treatment of these patients was investigated for major procedure-related complications, recurrence, reintervention, morbidity, and mortality. Mean follow-up time was 3 months (range, 1-6 months). All massive bleeding was controlled by occlusive balloon catheters. Four fistulas were successfully sealed with stent-grafts, resulting in a technical success rate of 80%. One patient was circulatory stabilized by endovascular management but needed immediate further open surgery. There were no procedure-related major complications. Mean hospital stay after the initial endovascular intervention was 19 days. Rebleeding occurred in four patients (80%) after a free interval of 2 weeks or longer. During the follow-up period three patients needed reintervention. The in-hospital mortality was 20% and the 30-day mortality was 40%. The midterm outcome was poor, due to comorbidities or rebleeding, with a mortality of 80% within 6 months. In conclusion, endovascular repair is an efficient and safe method to stabilize patients with life-threatening bleeding arterioenteric fistulas in the emergent episode. However, in this group of patients with severe comorbidities, the risk of rebleeding is high and further intervention must be considered

  1. Developing A Framework for Low-Volume Road Implementation of Pervious Concrete Pavements

    OpenAIRE

    Sonia Rahman, BSc; Andrew B. Northmore, MASc, EIT; Vimy Henderson, PhD, PEng; Susan L. Tighe, PhD, PEng

    2015-01-01

    Pervious concrete pavement is one of the promising pavement technologies, as it can help overcome traditional pavement environmental impacts, assist with stormwater management, and provide an effective low impact development solution. There are many benefits associated with pervious concrete pavement such as assisting with water filtration, absorbing heavy metals and reducing pollution. The most significant aspect, which draws the attention of environmental agencies and cities and municipalit...

  2. Pavement Condition Survey in Kagawa Prefecture by ROMDAS<研究成果報告>

    OpenAIRE

    MAMUNUR, RASHID Mohammad; 角川, 浩二

    2006-01-01

    Highway is one of the most important areas among the various facilities of infrastructure. Therefore, most of the organizations related to the infrastructure management system pay higher attention to the pavement which is the most important facility of highway management. An effective pavement management system (PMS) helps to carry out all the preservation and necessary maintenance operations of the pavement. In order to implement a pavement management system, data collection that indicates e...

  3. Evaluation of portland cement concrete pavement with high slag content cement.

    Science.gov (United States)

    2013-10-01

    The performance of a section of concrete pavement built with 30 percent Ground Granulated Blast Furnace Slag (GGBFS) is compared to a control section of concrete pavement built with 25 percent GGBFS to determine if the higher slag content pavement is...

  4. Evaluation of the MIT-Scan-T2 for non-destructive PCC pavement thickness determination.

    Science.gov (United States)

    2008-07-01

    The MIT-Scan-T2 device is marketed as a non-destructive way to determine pavement thickness on both : HMA and PCC pavements. PCC pavement thickness determination is an important incentivedisincentive : measurement for the Iowa DOT and contractors. Th...

  5. Integrating Pavement Crack Detection and Analysis Using Autonomous Unmanned Aerial Vehicle Imagery

    Science.gov (United States)

    2015-03-27

    INTEGRATING PAVEMENT CRACK DETECTION AND ANALYSIS USING AUTONOMOUS UNMANNED AERIAL VEHICLE...protection in the United States. AFIT-ENV-MS-15-M-195 INTEGRATING PAVEMENT CRACK DETECTION AND ANALYSIS USING AUTONOMOUS UNMANNED AERIAL...APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. AFIT-ENV-MS-15-M-195 INTEGRATING PAVEMENT CRACK DETECTION AND ANALYSIS USING AUTONOMOUS

  6. ANALYSIS AND EVALUATION OF QUALITATIVE PARAMETERS OF HIGHWAY ASPHALT CONCRETE PAVEMENTS IN LITHUANIA

    Directory of Open Access Journals (Sweden)

    E. Petkevicius

    2006-01-01

    Full Text Available The quality of pavements is evaluated by the presence of such defects as: pot-holes, cracks, runs and others. An outward exhibition of defects is pavement evenness. The paper contains correlation dependences between evenness and defects. The critical pavement conditions when it is necessary to execute repair works are determined in the paper.

  7. Effects of moving dynamic tyre loads on tyre-pavement contact stresses

    CSIR Research Space (South Africa)

    Steyn, WJvdM

    2002-01-01

    Full Text Available The purpose of this paper is to indicate the effect that moving dynamic tyre loads has on the tyre-pavement contact stresses used in pavement analysis. Traditionally tyre loads (in pavement analysis) are modelled as constant loads applied through...

  8. Prediction of IRI in short and long terms for flexible pavements: ANN and GMDH methods

    NARCIS (Netherlands)

    Ziari, H.; Sobhani, J.; Ayoubinejad, J.; Hartmann, Timo

    2015-01-01

    Prediction of pavement condition is one of the most important issues in pavement management systems. In this paper, capabilities of artificial neural networks (ANNs) and group method of data handling (GMDH) methods in predicting flexible pavement conditions were analysed in three levels: in 1 year,

  9. Systematic review: tranexamic acid for upper gastrointestinal bleeding

    DEFF Research Database (Denmark)

    Klingenberg, S.L.; Langholz, S.E.; Gluud, Lise Lotte

    2008-01-01

    BACKGROUND: Tranexamic acid may reduce upper gastrointestinal bleeding and stabilize patients before endoscopic treatments. AIM: To review randomized trials on tranexamic acid for upper gastrointestinal bleeding. METHODS: Manual and electronic searches of The Cochrane Library, MEDLINE, EMBASE and...

  10. 14 CFR 23.1109 - Turbocharger bleed air system.

    Science.gov (United States)

    2010-01-01

    ... Induction System § 23.1109 Turbocharger bleed air system. The following applies to turbocharged bleed air... vapors following any probable failure or malfunction of the engine exhaust, hydraulic, fuel, or oil...

  11. Bleeding in cancer patients and its treatment: a review.

    Science.gov (United States)

    Johnstone, Candice; Rich, Shayna E

    2017-12-18

    Bleeding is a common problem in cancer patients, related to local tumor invasion, tumor angiogenesis, systemic effects of the cancer, or anti-cancer treatments. Existing bleeds can also be exacerbated by medications such as bevacizumab, nonsteroidal anti-inflammatory drugs (NSAIDs), and anticoagulants. Patients may develop acute catastrophic bleeding, episodic major bleeding, or low-volume oozing. Bleeding may present as bruising, petechiae, epistaxis, hemoptysis, hematemesis, hematochezia, melena, hematuria, or vaginal bleeding. Therapeutic intervention for bleeding should start by establishing goals of care, and treatment choice should be guided by life expectancy and quality of life. Careful thought should be given to discontinuation of medications and reversal of anticoagulation. Interventions to stop or slow bleeding may include systemic agents or transfusion of blood products. Noninvasive local treatment options include applied pressure, dressings, packing, and radiation therapy. Invasive local treatments include percutaneous embolization, endoscopic procedures, and surgical treatment.

  12. Breast cancer recurrence after reoperation for surgical bleeding

    DEFF Research Database (Denmark)

    Pedersen, Rikke Nørgaard; Bhaskaran, K; Heide-Jørgensen, U

    2017-01-01

    BACKGROUND: Bleeding activates platelets that can bind tumour cells, potentially promoting metastatic growth in patients with cancer. This study investigated whether reoperation for postoperative bleeding is associated with breast cancer recurrence. METHODS: Using the Danish Breast Cancer Group d...

  13. Recycled asphalt pavement – fly ash geopolymer as a sustainable stabilized pavement material

    Science.gov (United States)

    Horpibulsuk, S.; Hoy, M.; Witchayaphong, P.; Rachan, R.; Arulrajah, A.

    2017-11-01

    Strength, durability, microstructure and leachate characteristics of Recycled Asphalt Pavement and Fly Ash (RAP-FA) geopolymers and RAP-FA blends as a sustainable pavement material are evaluated in this paper. The strength development of the stabilized materials with and without effect wetting-drying (w-d) cycles was determined by Unconfined Compression Strength (UCS) test. The mineralogical and microstructural changes of the stabilized material were analyzed by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The leachability of the heavy metals were measured by Toxicity Characteristic Leaching Procedure (TCLP) and compared with international standard. The results show that both RAP-FA blend and RAP-FA geopolymer increase with increasing the number of w-d cycles (C), reaching its peak at 6 w-d cycles. The XRD and SEM analyses indicate that the strength development of RAP-FA blend occurs due to stimulation of the chemical reaction between the high amount to Calcium in RAP and the high amount of Silica and Alumina in FA leaching to production of Calcium Aluminium (Silicate) Hydrate, while the geopolymerization reaction is observed in RAP-FA geopolymer. For C> 6, the significant macro- and micro-cracks developed during w-d cycles cause strength reduction for both RAP-FA blend and geopolymer. The TCLP results demonstrate that there is no environmental risk for these stabilized materials. Furthermore, FA-geopolymer can reduce the leachability of heavy metal in RAP-FA blend. The outcome from this research confirms the viability of using RAP-FA blend and RAP-FA geopolymer as alternative sustainable pavement materials.

  14. Stormwater quality of spring-summer-fall effluent from three partial-infiltration permeable pavement systems and conventional asphalt pavement.

    Science.gov (United States)

    Drake, Jennifer; Bradford, Andrea; Van Seters, Tim

    2014-06-15

    This study examined the spring, summer and fall water quality performance of three partial-infiltration permeable pavement (PP) systems and a conventional asphalt pavement in Ontario. The study, conducted between 2010 and 2012, compared the water quality of effluent from two Interlocking Permeable Concrete Pavements (AquaPave(®) and Eco-Optiloc(®)) and a Hydromedia(®) Pervious Concrete pavement with runoff from an Asphalt control pavement. The usage of permeable pavements can mitigate the impact of urbanization on receiving surface water systems through quantity control and stormwater treatment. The PP systems provided excellent stormwater treatment for petroleum hydrocarbons, total suspended solids, metals (copper, iron, manganese and zinc) and nutrients (total-nitrogen and total-phosphorus) by reducing event mean concentrations (EMC) as well as total pollutant loadings. The PPs significantly reduced the concentration and loading of ammonia (NH4(+)+NH3), nitrite (NO2(-)) and organic-nitrogen (Org-N) but increased the concentration and loading of nitrate (NO3(-)). The PP systems had mixed performances for the treatment of phosphate (PO4(3-)). The PP systems increased the concentration of sodium (Na) and chloride (Cl) but EMCs remained well below recommended levels for drinking water quality. Relative to the observed runoff, winter road salt was released more slowly from the PP systems resulting in elevated spring and early-summer Cl and Na concentrations in effluent. PP materials were found to introduce dissolved solids into the infiltrating stormwater. The release of these pollutants was verified by additional laboratory scale testing of the individual pavement and aggregate materials at the University of Guelph. Pollutant concentrations were greatest during the first few months after construction and declined rapidly over the course of the study. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Urban evaporation rates for water-permeable pavements.

    Science.gov (United States)

    Starke, P; Göbel, P; Coldewey, W G

    2010-01-01

    In urban areas the natural water balance is disturbed. Infiltration and evaporation are reduced, resulting in a high surface runoff and a typical city climate, which can lead to floods and damages. Water-permeable pavements have a high infiltration rate that reduces surface runoff by increasing the groundwater recharge. The high water retention capacity of the street body of up to 51 l/m(2) and its connection via pores to the surface lead to higher evaporation rates than impermeable surfaces. A comparison of these two kinds of pavements shows a 16% increase in evaporation levels of water-permeable pavements. Furthermore, the evaporation from impermeable pavements is linked directly to rain events due to fast-drying surfaces. Water-permeable pavements show a more evenly distributed evaporation after a rain event. Cooling effects by evaporative heat loss can improve the city climate even several days after rain events. On a large scale use, uncomfortable weather like sultriness or dry heat can be prevented and the urban water balance can be attenuated towards the natural.

  16. Update to Permeable Pavement Research at the Edison ...

    Science.gov (United States)

    The EPA’s Urban Watershed Management Branch (UWMB) has been monitoring the permeable pavement demonstration site at the Edison Environmental Center, NJ since 2010. This site has three different types of permeable pavements including interlocking concrete permeable pavers, pervious concrete, and porous asphalt. The permeable pavements are limited to parking spaces while adjacent driving lanes are impermeable and drain to the permeable surfaces. The parking lot is instrumented for continuous monitoring with thermistors and water content reflectometers that measure moisture as infiltrate passes through the storage gallery beneath the permeable pavements into the underlying native soil. Each permeable surface of the parking lot has four lined sections that capture infiltrate in tanks for water quality analyses; these tanks are capable of holding volumes up to 4.1 m3, which represents up to 38 mm (1.5 in.) for direct rainfall on the porous pavement and runoff from adjacent driving lanes that drain into the permeable surface.Previous technical releases concerning the demonstration site focused on monitoring techniques, observed chloride and nutrient concentrations, surface hydrology, and infiltration and evaporation rates. This presentation summarizes these past findings and addresses current water quality efforts including pH, solids analysis, total organic carbon, and chemical oxygen demand. Stormwater runoff continues to be a major cause of water pollution in

  17. Experimental Study on Color Durability of Color Asphalt Pavement

    Science.gov (United States)

    Ning, Shi; Huan, Su

    2017-06-01

    Aiming at the poor Color durability and the lack of research on Color asphalt pavement, spraying an anti-tire trace seal resin emulsion on the surface, a Color durable asphalt pavement was proposed. After long-term rolling and long-term aging test, the Color durability was evaluated by RGB function in Photoshop and trace residue rate formula. Test results proved that the Evaluation method was simple and effective. After long-term rolling, the Color of the road surface tends to a constant value. Spraying the emulsion on the road surface can resist tire traces. After long-term aging test, the resistance to tire traces was increased by 26.6% compared with the conventional type, while the former was 44.1% higher than the latter without long-term aging. The Color durable asphalt pavement can effectively improve the ability of Color asphalt pavement to resist tire traces, and significantly improve the Color durability of Color asphalt pavement.

  18. Automatic Pavement Crack Recognition Based on BP Neural Network

    Directory of Open Access Journals (Sweden)

    Li Li

    2014-02-01

    Full Text Available A feasible pavement crack detection system plays an important role in evaluating the road condition and providing the necessary road maintenance. In this paper, a back propagation neural network (BPNN is used to recognize pavement cracks from images. To improve the recognition accuracy of the BPNN, a complete framework of image processing is proposed including image preprocessing and crack information extraction. In this framework, the redundant image information is reduced as much as possible and two sets of feature parameters are constructed to classify the crack images. Then a BPNN is adopted to distinguish pavement images between linear and alligator cracks to acquire high recognition accuracy. Besides, the linear cracks can be further classified into transversal and longitudinal cracks according to the direction angle. Finally, the proposed method is evaluated on the data of 400 pavement images obtained by the Automatic Road Analyzer (ARAN in Northern China and the results show that the proposed method seems to be a powerful tool for pavement crack recognition. The rates of correct classification for alligator, transversal and longitudinal cracks are 97.5%, 100% and 88.0%, respectively. Compared to some previous studies, the method proposed in this paper is effective for all three kinds of cracks and the results are also acceptable for engineering application.

  19. Fatigue Life Assessment of Orthotropic Steel Deck with UHPC Pavement

    Directory of Open Access Journals (Sweden)

    Xu Jiang

    2017-01-01

    Full Text Available In recent years, a number of large-span bridges with orthotropic steel decks were constructed in China. With increasing traffic volumes and higher wheel loads, many fatigue cracks developed at the welds and the edge of cut-out holes. This paper aims at presenting the numerical analysis on the fatigue performance of the orthotropic steel deck using ultrahigh performance concrete (UHPC overlay as the deck pavement instead of the conventional asphalt concrete pavement. By using finite element method (FEM model, stress distribution at fatigue sensitive locations under the action of wheel loads is characterized and the obtained stress ranges indicate that the UHPC pavement significantly reduces the magnitude of the stress peak valued. A suggested truck stream model based on the weigh-in-motion (WIM data of four bridges in China is employed to calculate the stress variation at specific fatigue details. Furthermore, the fatigue damage accumulation at fatigue details under the UHPC and conventional asphalt concrete pavement is studied based on Miner’s linear cumulative damage rule and the rain-flow method. The results indicate that the UHPC pavement on the orthotropic steel deck can extend the service lives of the concerned regions over 100 years, but the fatigue lives will reduce significantly when the elastic modulus of UHPC decreases to 50% of the original value.

  20. Perpetual pavement – absorbing stress and functional maintenance

    Directory of Open Access Journals (Sweden)

    Rong Gao

    2017-03-01

    Full Text Available Perpetual Pavement combines the well documented smoothness and safety advantages of asphalt with an advanced, multi-layer paving design process, that with routine maintenance, extends the useful life of a roadway. Perpetual provides long lasting road and smoothness for the construction purposes. This study has the design key points of perpetual pavement based on the idea of life cycle, which has a new direction for the new highway construction, reconstruction and expansion. First, the structure of long life pavement design is studied to analyze the effect of stress absorbing layer. Second, researches on stress absorbing layer from the aspects of raw materials, mix proportion are implemented. Third, the design index of stress absorbing layer is determined by the shear strength test. The results show that the design idea of composite perpetual pavement can be realized by reasonable design of the stress absorbing layer and carrying out the surface functional maintenance can ensure the pavement to avoid structural damage in the operation stage.

  1. A User Friendly Software for Rigid Pavement Design

    Directory of Open Access Journals (Sweden)

    Aydın Kıcı

    2017-12-01

    Full Text Available Concrete pavements as concrete road slab, appear as a strong alternative for flexible superstructures especially because of their low cost for maintenance and repair and the high performance they show under heavy axle loads. The design of these concrete road slabs is quite different from the traditional concrete and reinforced concrete structures’ design. In the design for this kind of pavements, traffic conditions should be defined properly and considered an addition to the concrete and platform properties. There have been designing methods developed based on both experimental and mechanic foundations for concrete pavements. The most important ones of these methods are AASHTO (1993 and PCA (1984. In both design methods, it’s significant to know the maximum deflections and maximum strains the vehicles’ loads cause on the pavement. The calculation of this maximum deflections and maximum strains can be done via the finite element method or the closed formulas which have been developed by Westergaard. In this study, a user-friendly software has been developed based on AASHTO 1993, PCA 1984 design methods and Westergaard formulas. Thanks to this software, the user who wants to design the concrete pavement as concrete road slab can obtain the essential parameters automatically by entering the required data for the design.

  2. 14 CFR 23.1111 - Turbine engine bleed air system.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Turbine engine bleed air system. 23.1111... Induction System § 23.1111 Turbine engine bleed air system. For turbine engine bleed air systems, the following apply: (a) No hazard may result if duct rupture or failure occurs anywhere between the engine port...

  3. Colonoscopic examination of rectal bleeding in children: A report of ...

    African Journals Online (AJOL)

    Rectal bleeding in children is a frightening and cause of great concern, and of parental anxiety. In this report, we present the value of colonoscopy to unravel the diagnostic conundrum often associated with rectal bleeding in children. Key words: Children, colonoscopy, juvenile polyps, rectal bleeding ...

  4. Leech as a cause of abnormal vaginal bleeding: Presentation of ...

    African Journals Online (AJOL)

    Leech bites are a recognized cause of bleeding from any human orifice upon exposure to water which is infested with leeches. A high level of suspicion is necessary to make the diagnosis and institute cost-effective definitive treatment for leech bite induced bleeding including vaginal bleeding as has been revealed by the ...

  5. No increased systemic fibrinolysis in women with heavy menstrual bleeding

    NARCIS (Netherlands)

    Wiewel-Verschueren, S.; Knol, H. M.; Lisman, T.; Bogchelman, D. H.; Kluin-Nelemans, J. C.; van der Zee, A.G.J.; Mulder, A.B.; Meijer, K.

    BackgroundBleeding disorders have been recognized as important etiologic or contributory factors in women with heavy menstrual bleeding. Fibrinolysis in the endometrium plays a role in heavy menstrual bleeding. It is unknown whether increased systemic fibrinolysis might also increase the risk of

  6. Small intestinal diverticulum with bleeding: Case report and literature review.

    Science.gov (United States)

    Zhao, Lifang; Lu, Wei; Sun, Yinping; Liang, Junrong; Feng, Shanshan; Shi, Yongquan; Wu, Qiong; Wang, Jianhong; Wu, Kaichun

    2018-03-01

    Small intestinal diverticulum with bleeding is an important reason for obscure gastrointestinal bleeding (OGB) , in addition to tumor and vascular diseases. Small intestinal diverticulum with bleeding is difficult to detect by barium meal and angiographic methods and has been regarded as an important cause of obscure gastrointestinal tract bleeding in adolescents. Because of its complicated etiology and non-specific clinical manifestations, it is relatively difficult to detect small intestinal diverticulum with bleeding, especially in patients with a large amount of bleeding and hemodynamic instability. This retrospective study collects clinical statistics of 19 patients admitted to our hospital from January 2010 to December 2016. Patients who had small intestinal diverticulum patients with bleeding were included in this study. Patients who were taking anticoagulants were excluded DIAGNOSES:: Small intestinal diverticulum patients with bleeding. This retrospective study describes the clinical features of patients with small intestinal diverticulum whose main symptom was gastrointestinal bleeding and analyze the literature on this topic, with particular reference to the clinical characteristics, pathological features, and choice of examination methods. Small intestinal diverticulum with bleeding is a common cause of obscure gastrointestinal bleeding, but it is difficult to detect using normal examination methods. For patients with repeated gastrointestinal bleeding and no positive results found on gastroscopy and colonoscopy, endoscopy of the small intestine and CTE with contrast can be considered as a diagnostic modality.

  7. Development of a pavement management system for Virginia : final report on phase I : application and verification of a pilot pavement condition inventory for Virginia interstate flexible pavements.

    Science.gov (United States)

    1984-01-01

    The study reported here addresses some of the earlier phases in the development of a pavement management system for the state of Virginia. Among the issues discussed are the development of an adequate data base and the implementation of a condition r...

  8. Helping mothers survive bleeding after birth

    DEFF Research Database (Denmark)

    Nelissen, Ellen; Ersdal, Hege; Ostergaard, Doris

    2014-01-01

    OBJECTIVE: To evaluate "Helping Mothers Survive Bleeding After Birth" (HMS BAB) simulation-based training in a low-resource setting. DESIGN: Educational intervention study. SETTING: Rural referral hospital in Northern Tanzania. POPULATION: Clinicians, nurse-midwives, medical attendants, and ambul......OBJECTIVE: To evaluate "Helping Mothers Survive Bleeding After Birth" (HMS BAB) simulation-based training in a low-resource setting. DESIGN: Educational intervention study. SETTING: Rural referral hospital in Northern Tanzania. POPULATION: Clinicians, nurse-midwives, medical attendants...... low (3% pass rate for basic delivery and management of postpartum hemorrhage). CONCLUSIONS: The HMS BAB simulation-based training has potential to contribute to education of health care providers. We recommend a full day of training and validation of the facilitators to improve the training....

  9. Treatment and prognosis in peptic ulcer bleeding.

    Science.gov (United States)

    Laursen, Stig Borbjerg

    2014-01-01

    Peptic ulcer bleeding is a frequent cause of admission. Despite several advances in treatment the 30-day mortality seems unchanged at a level around 11%. Use of risk scoring systems is shown to be advantageous in the primary assessment of patients presenting with symptoms of peptic ulcer bleeding. Studies performed outside Denmark have demonstrated that use of risk scoring systems facilitates identification of low-risk patients suitable for outpatient management. Nevertheless, these systems have not been implemented for routine use in Denmark. This is mainly explained by concerns about the external validity due to considerable inter-country variation in patients' characteristics. In recent years, transcatheter arterial embolization (TAE) has become increasingly used for achievement of hemostasis in patients with peptic ulcer bleeding not responding to endoscopic therapy. As rebleeding is associated with poor outcome TAE could, in theory, also be beneficial as a supplementary treatment in patients with ulcer bleeding responding to endoscopic therapy. This has not been examined previously. Several studies have concluded that peptic ulcer bleeding is associated with excess long-term mortality. These findings are, however, questioned as the studies were based on life-table analysis, unmatched control groups, or did not perform adequate adjustment for comorbidity. Treatment with blood transfusion is, among patients undergoing cardiac bypass surgery, shown to increase the long-term mortality. Despite frequent use of blood transfusion in treatment of peptic ulcer bleeding a possible adverse effect of on long-term survival has not been examined in these patients. The aims of the present thesis were: 1. To examine which risk scoring system is best at predicting need of hospital-based intervention, rebleeding, and mortality in patients presenting with upper gastrointestinal bleeding (Study I) 2. To evaluate if supplementary transcatheter arterial embolization (STAE) after

  10. [Bleeding gastric inflammatory fibroid polyp (Vanek's tumor)].

    Science.gov (United States)

    Guţu, E; Ghidirim, Gh; Mişin, I; Iakovleva, Iraida; Vozian, M

    2010-01-01

    Inflammatory fibroid polyp's (IFP) or Vanek tumor of the gastrointestinal tract represents a relatively unusual entity. IFP is an extremely rare cause of upper gastrointestinal bleeding. We report herein a case of a 30-year-old woman who had a gastric IFP complicated by gastrointestinal bleeding and obstructive symptoms. The lesion was mistaken on endoscopic, radiologic examination and in the operating room for a gastrointestinal stromal tumor (GIST). Preoperative endoscopic examination revealed a protruding oval-shaped submucosal lesion (approximately 7 cm in size) of the gastric antrum, with ulceration of the mucosal surface. Multiple endoscopic biopsies were negative for neoplastic changes. Barium meal study disclosed a large tumor in the prepyloric area of the stomach. Presumptive preoperative diagnosis was GIST. Subtotal Bilroth II gastrectomy en bloc with the mass and lymphadenectomy was performed. Surprisingly, the final histological diagnosis was IFP. Postoperative course was uneventful and no recurrences were observed during 4 years follow-up. With reference to case report, the etiology, diagnosis and treatment strategy of IFP will be discussed. This case highlights an unusual presentation of IFP. Although bleeding may represent a rare complication due IFP, it should be considered in the differential diagnosis of upper gastrointestinal hemorrhage of uncertain etiology.

  11. Geo synthetic-reinforced Pavement systems; Sistemas de pavimentos reforzados con geosinteticos

    Energy Technology Data Exchange (ETDEWEB)

    Zornberg, J. G.

    2014-02-01

    Geo synthetics have been used as reinforcement inclusions to improve pavement performance. while there are clear field evidence of the benefit of using geo synthetic reinforcements, the specific conditions or mechanisms that govern the reinforcement of pavements are, at best, unclear and have remained largely unmeasured. Significant research has been recently conducted with the objectives of: (i) determining the relevant properties of geo synthetics that contribute to the enhanced performance of pavement systems, (ii) developing appropriate analytical, laboratory and field methods capable of quantifying the pavement performance, and (iii) enabling the prediction of pavement performance as a function of the properties of the various types of geo synthetics. (Author)

  12. Treatment Modalities in Adolescents Who present With Heavy Menstrual Bleeding.

    Science.gov (United States)

    Alaqzam, Tasneem S; Stanley, Angela C; Simpson, Pippa M; Flood, Veronica H; Menon, Seema

    2018-03-07

    This study sought to determine the relationship of bleeding disorders to iron deficiency anemia. Additionally, this study was undertaken to examine all current treatment modalities used in a menorrhagia clinic with respect to heavy menstrual bleeding management to identify the most effective options for menstrual management in the setting of an underlying bleeding disorder. DESIGN, SETTING, PARTICIPANT, INTERVENTION, AND MAIN OUTCOME MEASURES: Retrospective chart review of adolescent <21 years with heavy menstrual bleeding attending a multidisciplinary hematology-adolescent gynecology clinic. Information included demographics, bleeding diathesis, hematologic parameters, treatment, and the diagnosis was extracted from each chart. Subjects were grouped into two categories based on the diagnosis of a bleeding disorder. Hemoglobin level, iron deficiency anemia, and need for transfusion were compared between a bleeding disorder and no bleeding disorder group. Subjects were grouped into categories depending on hormonal modality and treatment success of the groups were compared. 73 subjects tested for a bleeding disorder. Of the subjects completing testing, 34 (46%) were diagnosed with a bleeding disorders. 39 (54%) subjects had heavy menstrual bleeding due to other causes. There was no significant difference in hemoglobin between those with and without a bleeding disorder. Iron deficiency anemia was significantly higher in subjects without bleeding disorder. When comparing hormone therapy success, the levonorgestrel IUD (LNG-IUD) (89%) had the highest rate of menstrual suppression followed by norethindrone acetate 5-10mg/day (83%), and the transdermal patch (80%). All subjects using both tranexamic acid and hormonal therapy had 100% achievement of menstrual suppression. A high frequency of bleeding disorder was found in those tested. Subjects with a bleeding disorder were less likely to present with severe anemia requiring blood transfusion and less likely to have iron

  13. Comparing Bleeding Risk Assessment Focused on Modifiable Risk Factors Only Versus Validated Bleeding Risk Scores in Atrial Fibrillation

    DEFF Research Database (Denmark)

    Guo, Yutao; Zhu, Hang; Chen, Yundai

    2018-01-01

    predictive ability for major bleeding (c-index 0.63, 95% confidence interval 0.56-0.69) and intracranial hemorrhage (0.72, 0.65-0.79) but nonsignificantly (and poorly) predicted extracranial bleeding (0.55, 0.54-0.56; P = .361). The HAS-BLED score was superior to predict bleeding events compared...

  14. Bleeding risk in 'real world' patients with atrial fibrillation: comparison of two established bleeding prediction schemes in a nationwide cohort

    DEFF Research Database (Denmark)

    Olesen, J B; Lip, G Y H; Hansen, P R

    2011-01-01

    Oral anticoagulation (OAC) in patients with atrial fibrillation (AF) is a double-edged sword, because it decreases the risk of stroke at the cost of an increased risk of bleeding. We compared the performance of a new bleeding prediction scheme, HAS-BLED, with an older bleeding prediction scheme...

  15. Pavement Subgrade Performance Study in the Danish Road Testing Machine

    DEFF Research Database (Denmark)

    Ullidtz, Per; Ertman Larsen, Hans Jørgen

    1997-01-01

    Most existing pavement subgrade criteria are based on the AASHO Road Test, where only one material was tested and for only one climatic condition. To study the validity of these criteria and to refine the criteria a co-operative research program entitled the "International Pavement Subgrade...... Performance Study" was sponsored by the FHWA with American, Finnish and Danish partners. This paper describes the first test series which was carried out in the Danish Road Testing Machine (RTM).The first step in this program is a full scale test on an instrumented pavement in the Danish Road Testing Machine....... Pressure gauges and strain cells were installed in the upper part of the subgrade, for measuring stresses and strains in all three directions. During and after construction FWD testing was carried out to evaluate the elastic parameters of the materials. These parameters were then used with the theory...

  16. Application of Artificial Intelligence for Optimization in Pavement Management

    Directory of Open Access Journals (Sweden)

    Reus Salini

    2015-07-01

    Full Text Available Artificial intelligence (AI is a group of techniques that have quite a potential to be applied to pavement engineering and management. In this study, we developed a practical, flexible and out of the box approach to apply genetic algorithms to optimizing the budget allocation and the road maintenance strategy selection for a road network. The aim is to provide an alternative to existing software and better fit the requirements of an important number of pavement managers. To meet the objectives, a new indicator, named Road Global Value Index (RGVI, was created to contemplate the pavement condition, the traffic and the economic and political importance for each and every road section. This paper describes the approach and its components by an example confirming that genetic algorithms are very effective for the intended purpose.

  17. Effects of Pavement Skid Resistance on Traffic Accidents

    Directory of Open Access Journals (Sweden)

    Abdullah I. Al-Mansour

    2006-12-01

    Full Text Available The Ministry of Transport (MOT in the Kingdom of Saudi Arabia had collected a massive amount of friction measurements using a Mu-meter covering most of the major highway network in the kingdom. Traffic accident data of 89 high accident rate locations from four main different highway classes were extracted from the MOT accident records. Pavement skid resistance for the selected locations was determined from the pavement skid resistance records. The objective of this paper is to utilize these data to investigate the effects of pavement skid resistance on traffic accidents. The analysis included establishing relationships between skid resistance and accident number, accident significance and accident density. It was determined that a decreasing skid resistance leads to an increase in traffic accidents. Acritical value of skid resistance was also established based on number, significance and density of accidents.

  18. Design prediction of pavement skid resistance from laboratory tests

    Science.gov (United States)

    Parcells, W. H.; Metheny, T. M.; Maag, R. G.

    1980-08-01

    Methods for preevaluating aggregates and paving mixtures so that predictions can be made covering skid resistance properties of proposed and in service pavement types are discussed. A correlation was established between the field testing using the data from the British Portable Tester and the Locked Wheel Pavement Friction Trailer at speeds of 40 and 55 mph. Core samples were extracted from the Locked Wheel Tester Skid Path and subjected to wear on the small wheel circular track with periodic surface friction testing. The final step was to remix and remold the cored pavement samples or make samples with new materials to obtain an 'as new' surface and again subject these samples to wear on the small wheel circular track with periodic testing.

  19. Pavement maintenance optimization model using Markov Decision Processes

    Science.gov (United States)

    Mandiartha, P.; Duffield, C. F.; Razelan, I. S. b. M.; Ismail, A. b. H.

    2017-09-01

    This paper presents an optimization model for selection of pavement maintenance intervention using a theory of Markov Decision Processes (MDP). There are some particular characteristics of the MDP developed in this paper which distinguish it from other similar studies or optimization models intended for pavement maintenance policy development. These unique characteristics include a direct inclusion of constraints into the formulation of MDP, the use of an average cost method of MDP, and the policy development process based on the dual linear programming solution. The limited information or discussions that are available on these matters in terms of stochastic based optimization model in road network management motivates this study. This paper uses a data set acquired from road authorities of state of Victoria, Australia, to test the model and recommends steps in the computation of MDP based stochastic optimization model, leading to the development of optimum pavement maintenance policy.

  20. Determination of Pavement Rehabilitation Activities through a Permutation Algorithm

    Directory of Open Access Journals (Sweden)

    Sangyum Lee

    2013-01-01

    Full Text Available This paper presents a mathematical programming model for optimal pavement rehabilitation planning. The model maximized the rehabilitation area through a newly developed permutation algorithm, based on the procedures outlined in the harmony search (HS algorithm. Additionally, the proposed algorithm was based on an optimal solution method for the problem of multilocation rehabilitation activities on pavement structure, using empirical deterioration and rehabilitation effectiveness models, according to a limited maintenance budget. Thus, nonlinear pavement performance and rehabilitation activity decision models were used to maximize the objective functions of the rehabilitation area within a limited budget, through the permutation algorithm. Our results showed that the heuristic permutation algorithm provided a good optimum in terms of maximizing the rehabilitation area, compared with a method of the worst-first maintenance currently used in Seoul.

  1. Factors Influencing Stormwater Mitigation in Permeable Pavement

    Directory of Open Access Journals (Sweden)

    Chun Yan Liu

    2017-12-01

    Full Text Available Permeable pavement (PP is used worldwide to mitigate surface runoff in urban areas. Various studies have examined the factors governing the hydrologic performance of PP. However, relatively little is known about the relative importance of these governing factors and the long-term hydrologic performance of PP. This study applied numerical models—calibrated and validated using existing experimental results—to simulate hundreds of event-based and two long-term rainfall scenarios for two designs of PP. Based on the event-based simulation results, rainfall intensity, rainfall volume, thickness of the storage layer and the hydraulic conductivity of the subgrade were identified as the most influential factors in PP runoff reduction. Over the long term, PP performed significantly better in a relatively drier climate (e.g., New York, reducing nearly 90% of runoff volume compared to 70% in a relatively wetter climate (e.g., Hong Kong. The two designs of PP examined performed differently, and the difference was more apparent in the relatively wetter climate. This study generated insights that will help the design and implementation of PP to mitigate stormwater worldwide.

  2. Jejunal Diverticula Causing Unusual Massive Lower Gastrointestinal Bleeding

    Directory of Open Access Journals (Sweden)

    Chiong-Hee Wong

    2008-09-01

    Full Text Available Jejunal diverticula are rare and difficult to diagnose. They are often asymptomatic, but they may infrequently cause serious acute complications, such as diverticulitis with or without perforation, volvulus, intussusception, or hemorrhage. Hemorrhage of jejunal diverticula usually presents as lower gastrointestinal bleeding. Diverticula with bleeding may be associated with some anticoagulants, antiplatelets or nonsteroidal antiinflammatory agents in the elderly. In our case, upper gastroscopy and colonoscopy could not easily disclose the bleeding. Selective mesenteric angiography is the gold standard for diagnosis of active and fatal bleeding. The management of a bleeding jejunal diverticulum is surgical resection of the involved segment of jejunum.

  3. [ENDOSCOPIC INJECTION TREATMENT OF BLEEDING PEPTIC ULCER

    Science.gov (United States)

    Díaz, Freddy; Contardo, Carlos; Román, Rossana; Eduardo, Vesco; Dávalos, Milagros; Velásquez, Hermes; Soriano, César; Espejo, Hernán

    1997-01-01

    BACKGROUND: Objectives were two. (1) to determine theefficiency of the endoscopic injection therapy (EIT) in patients suffering from bleeding caused by peptic ulcer disease with high risk of recurrence, and (2) to recognize clinical and endoscopical risk factors that influence recurrence of hemorrhage and mortality from this pathology. METHODS: This is a retrospective study that included 121 patients, who were admitted by a unit specialized in managing gastrointestinal hemorrhage owing to peptic ulcer with active bleeding or non-bleeding visible vessel, and who underwent EIT with epinephrine between March, 1994 and February, 1996.RESULTS: Initial success was achieved in 119 patients who underwent EIT (99,1%). Bleeding persisted in one patient (0,9%), and in another one, EIT was not sucessful because of inaccessible location. Definite hemostasis was achieved in 93 patients (77,5%) and there was recurrence in 28 cases (23,5%). Twenty-six patients underwent surgical therapy (21,5%). The univariable analysis showed that hemorrhage recurrence was related to the presence of shock (p = 0,002), hematemesis (p = 0,2), age over 60 (p = 0,009), number of blood units transfused (p = 0,00000) and ulcer diameter larger than 2 cm (p = 0,018). The global mortality in our patients was of 10%, and surgical mortality was of 34,6%. Factors significantly related to mortality were hemorrhage recurrence (p = 0,000003), presence of concomitant disease (p = 0,05), and presence of gastric ulcer (p = 0,021), in addition to age (over 60), presence of shock and ulcer diameter larger than 2 cm (p = 0,05).CONCLUSION: EIT is a valuable procedure for the treatment of hemorrhage caused by peptic ulcer with high risk of recurrence (active hemorrhage or visible vessel), with a definite hemostasis of 77,5%. The presence of shock, hematemesis, age over 60, transfusion requirements of more than 3 blood units, and ulcer diameter of more than 2 cm are factors that increase the probability of hemorrhage

  4. Numerical Study of Tire Hydroplaning Based on Power Spectrum of Asphalt Pavement and Kinetic Friction Coefficient

    Directory of Open Access Journals (Sweden)

    Shengze Zhu

    2017-01-01

    Full Text Available Hydroplaning is a driving phenomenon threating vehicle’s control stability and safety. It happens when tire rolls on wet pavement with high speed that hydrodynamic force uplifts the tire. Accurate numerical simulation to reveal the mechanism of hydroplaning and evaluate the function of relevant factors in this process is significant. In order to describe the friction behaviors of tire-pavement interaction, kinetic friction coefficient curve of tire rubber and asphalt pavement was obtained by combining pavement surface power spectrum and complex modulus of tread rubber through Persson’s friction theory. Finite element model of tire-fluid-pavement was established in ABAQUS, which was composed of a 225-40-R18 radial tire and three types of asphalt pavement covered with water film. Mechanical responses and physical behaviors of tire-pavement interaction were observed and compared with NASA equation to validate the applicability and accuracy of this model. Then contact force at tire-pavement interface and critical hydroplaning speed influenced by tire inflation pressure, water film thickness, and pavement types were investigated. The results show higher tire inflation pressure, thinner water film, and more abundant macrotexture enhancing hydroplaning speed. The results could be applied to predict hydroplaning speed on different asphalt pavement and improve pavement skid resistance design.

  5. Deterioration modeling for condition assessment of flexible pavements considering extreme weather events

    Science.gov (United States)

    Hashemi Tari, Yasamin; Shahini Shamsabadi, Salar; Birken, Ralf; Wang, Ming

    2015-04-01

    Accurate pavement management systems are essential for states' Department Of Transportation and roadway agencies to plan for cost-effective maintenance and repair (M and R) strategies. Pavement deterioration model is an imperative component of any pavement management system since the future budget and M and R plans would be developed based on the predicted pavement performance measures. It is crucial for the pavement deterioration models to consider the factors that significantly aggravate the pavement condition. While many studies have highlighted the impact of different environmental, load, and pavement's structure on the life cycle of the pavement, effect of extreme weather events such as Floods and Snow Storms have often been overlooked. In this study, a pavement deterioration model is proposed which would consider the effect of traffic loads, climate conditions, and extreme weather events. Climate, load and performance data has been compiled for over twenty years and for eight states using the Long Term Pavement Performance (LTPP) and National Oceanic and Atmospheric Administration (NOAA) databases. A stepwise regression approach is undertaken to quantify the effect of the extreme weather events, along with other influential factors on pavement performance in terms of International Roughness Index (IRI). Final results rendered more than 90% correlation with the quantified impact values of extreme weather events.

  6. Study on the Vehicle Dynamic Load Considering the Vehicle-Pavement Coupled Effect

    Science.gov (United States)

    Xu, H. L.; He, L.; An, D.

    2017-11-01

    The vibration of vehicle-pavement interaction system is sophisticated random vibration process and the vehicle-pavement coupled effect was not considered in the previous study. A new linear elastic model of the vehicle-pavement coupled system was established in the paper. The new model was verified with field measurement which could reflect the real vibration between vehicle and pavement. Using the new model, the study on the vehicle dynamic load considering the vehicle-pavement coupled effect showed that random forces (centralization) between vehicle and pavement were influenced largely by vehicle-pavement coupled effect. Numerical calculation indicated that the maximum of random forces in coupled model was 2.4 times than that in uncoupled model. Inquiring the reason, it was found that the main vibration frequency of the vehicle non-suspension system was similar with that of the vehicle suspension system in the coupled model and the resonance vibration lead to vehicle dynamic load increase significantly.

  7. Functionality enhancement of industrialized optical fiber sensors and system developed for full-scale pavement monitoring.

    Science.gov (United States)

    Wang, Huaping; Liu, Wanqiu; He, Jianping; Xing, Xiaoying; Cao, Dandan; Gao, Xipeng; Hao, Xiaowei; Cheng, Hongwei; Zhou, Zhi

    2014-05-19

    Pavements always play a predominant role in transportation. Health monitoring of pavements is becoming more and more significant, as frequently suffering from cracks, rutting, and slippage renders them prematurely out of service. Effective and reliable sensing elements are thus in high demand to make prognosis on the mechanical properties and occurrence of damage to pavements. Therefore, in this paper, various types of functionality enhancement of industrialized optical fiber sensors for pavement monitoring are developed, with the corresponding operational principles clarified in theory and the performance double checked by basic experiments. Furthermore, a self-healing optical fiber sensing network system is adopted to accomplish full-scale monitoring of pavements. The application of optical fiber sensors assembly and self-healing network system in pavement has been carried out to validate the feasibility. It has been proved that the research in this article provides a valuable method and meaningful guidance for the integrity monitoring of civil structures, especially pavements.

  8. New findings regarding the significance of pavement skid resistance for road safety on Swiss freeways.

    Science.gov (United States)

    Lindenmann, H P

    2006-01-01

    The significance of the influence of poor pavement skid resistance values on accident frequency in wet pavement conditions has been the object of many studies over several years. The various investigations have produced very diverse findings. Only seldom, however, has detailed consideration been given to the central question of whether pavement skid resistance is a decisive parameter in the occurrence of local accident "black spots." Until now, the focus has been more on describing a relationship between pavement skid resistance and accident frequency. In the course of the network-wide survey of the states of pavements and of accident occurrence on Switzerland's freeways from 1999 to 2003, it emerged that a relationship with inadequate pavement skid resistance was provable for only a small proportion of accident black spots. These findings were used to frame a guideline for authorities and highway operators about how to treat skid resistance when assessing pavements and accident occurrence on freeways.

  9. Finite element analysis of GFRP reinforced concrete pavement under static load

    Science.gov (United States)

    Li, Shiping; Hu, Chunhua

    2018-02-01

    GFRP was more corrosion resistant than traditional reinforced, it is lightweight, high strength thermal expansion coefficient is more close to the concrete and a poor conductor of electromagnetic. Therefore, the use of GFRP to replace the traditional reinforcement in concrete pavement application has excellent practical value. This paper uses ANSYS to establish delamination and reinforcement of Pavement model and analyzed response of GFRP concrete and ordinary concrete pavement structural mechanics on effects of different factors under the action of static. The results showed that under static load, pavement surface layer presented similar changes on stress of surface layer, vertical and horizontal deformation in two kinds of pavement structure, but indicators of GFRP reinforced concrete pavement were obviously better than that of ordinary concrete pavement.

  10. Functionality Enhancement of Industrialized Optical Fiber Sensors and System Developed for Full-Scale Pavement Monitoring

    Directory of Open Access Journals (Sweden)

    Huaping Wang

    2014-05-01

    Full Text Available Pavements always play a predominant role in transportation. Health monitoring of pavements is becoming more and more significant, as frequently suffering from cracks, rutting, and slippage renders them prematurely out of service. Effective and reliable sensing elements are thus in high demand to make prognosis on the mechanical properties and occurrence of damage to pavements. Therefore, in this paper, various types of functionality enhancement of industrialized optical fiber sensors for pavement monitoring are developed, with the corresponding operational principles clarified in theory and the performance double checked by basic experiments. Furthermore, a self-healing optical fiber sensing network system is adopted to accomplish full-scale monitoring of pavements. The application of optical fiber sensors assembly and self-healing network system in pavement has been carried out to validate the feasibility. It has been proved that the research in this article provides a valuable method and meaningful guidance for the integrity monitoring of civil structures, especially pavements.

  11. Accelerated pavement testing efforts using the heavy vehicle simulator

    CSIR Research Space (South Africa)

    Du Plessis, Louw

    2017-10-01

    Full Text Available of the University of Costa Rica and the Mexico Institute of Trans- portation amongst others. Brief descriptions of HVS research and summaries of key results from these programs are provided. Planned research is covered where available. � 2017 Chinese Society...-empirical design models using laboratory materials testing characterization and real, long-term pavement performance monitoring and analysis data.https://doi.org/10.1016/j.ijprt.2017.09.016 1996-6814/� 2017 Chinese Society of Pavement Engineering. Production...

  12. Thin, applied surfacing for improving skid resistance of concrete pavements

    Science.gov (United States)

    Scholer, C. F.

    1980-12-01

    The use of select aggregate in a thin wearing surface of portland cement mortar to prolone or restore a concrete pavement's ability to develop high friction was accomplished. Two fine aggregates, blast furnace slag and lightweight expanded shale were found to exhibit skid resistance greater than the other aggregates evaluated. The British polishing wheel was used in the laboratory evaluation of aggregate to simulate wear. The need for a method of restoring friction to a worn, but otherwise sound concrete pavement led to a field evaluation of several different techniques for placing a very thin overlay. The successful method was a broomed, very thin layer of mortar, 3 mm thick.

  13. A pavement Moisture Accelerated Distress (MAD) identification system, volume 2

    Science.gov (United States)

    Carpenter, S. H.; Darter, M. I.; Dempsey, B. J.

    1981-09-01

    A users manual is designed which provides the engineer with a rational method of examining a pavement and determining rehabilitation needs that are related to the causes of the existing distress, particularly moisture related distress. The key elements in this procedure are the MAD Index developed in Volume 1, the Pavement Condition Index (PCI) and the Moisture Distress Index (MDI). Step by step procedures are presented for calculating each parameter. Complete distress identification manuals are included for asphalt surfaced highways and jointed reinforced concrete highways with pictures and descriptions of all major distress types. Descriptions of the role moisture plays in the development of each distress type are included.

  14. Risk factors for severity and recurrence of colonic diverticular bleeding

    Directory of Open Access Journals (Sweden)

    Joaquim Natércia

    Full Text Available Background: Colonic diverticular bleeding is the most common cause of lower gastrointestinal bleeding. Risk factors related to severity and repeated bleeding episodes are not completely clearly defined. Objective: To characterize a Portuguese population hospitalized due to colonic diverticular bleeding and to identify the clinical predictors related to bleeding severity and rebleeding. Methods: Retrospective analysis of all hospitalized patients diagnosed with colonic diverticular bleeding from January 2008 to December 2013 at our institution. The main outcomes evaluated were bleeding severity, defined as any transfusion support requirements and/or signs of hemodynamic shock, and 1-year recurrence rate. Results: Seventy-four patients were included, with a mean age of 75.7 ± 9.5 years; the majority were male (62.2%. Thirty-six patients (48.6% met the criteria for severe bleeding; four independent risk factors for severe diverticular bleeding were identified: low hemoglobin level at admission (≤ 11 g/dL; OR 18.8, older age (≥ 75 years; OR 4.7, bilateral diverticular location (OR 14.2 and chronic kidney disease (OR 5.6. The 1-year recurrence rate was 12.9%. We did not identify any independent risk factor for bleeding recurrence in this population. Conclusion: In this series, nearly half of the patients hospitalized with diverticular bleeding presented with severe bleeding. Patients with low hemoglobin levels, older age, bilateral diverticular location and chronic kidney disease had a significantly increased risk for severe diverticular bleeding. In addition, a small number of patients rebled within the first year after the index episode, although we could not identify independent risk factors associated with the recurrence of diverticular bleeding.

  15. Bearing capacity evaluation of rubblized concrete pavements

    Directory of Open Access Journals (Sweden)

    González, M.

    2009-03-01

    Full Text Available The paper presents the findings of a research work performed on a real scale concrete pavement project where Rubblizing technology was used for its structural rehabilitation. Rubblizing may be defined as a fracture technique in which a concrete pavement slab is transformed in a granular base with a very high Modulus. This technique, fractures the concrete slab in angular pieces by using a concentrated dynamic load of low amplitude and high frequency. The research work was based on field study on the rehabilitation of 5 km motorway. The structural evaluations where made, before, during and after one year construction. Measurements and site evaluation where made by using DCP, Light Weight Deflectometer and FWD (on top of asphalt layer and excavating inside pits. The structural capacity of the Rubblized layer was evaluated through theoretical analysis. Because of the anisotropic properties of the Rubblized layer the results are presented using AASHTO structural layer coefficient. The structural layer coefficients recommended are between the range of 0.25 and 0.30 for concrete slabs with thickness grater than 220 mm.El trabajo presenta los resultados de un estudio a escala real de la capacidad estructural de un firme de hormigón rehabilitado utilizando la técnica de Rubblizing. La técnica de Rubblizing ha sido traducida como el pulverizado del firme de hormigón pero, es más bien un efecto combinado de trituración y fracturación de la losa de hormigón en todo su espesor para convertir esta en una base granular de alto módulo. Esta tecnica fractura la losa de hormigón en trozos angulares y entrelazados empleando una carga dinámica concentrada, de baja amplitud y alta frecuencia. La investigación se basó en el estudio de la rehabilitación de 5 km de autopista. Los estudios de la capacidad estructural fueron realizados durante, al término y un año después de la construcción. Para las mediciones y evaluaciones de terreno se utilizó, el

  16. An Unusual Case of Gastrointestinal Bleeding

    Directory of Open Access Journals (Sweden)

    Kristin N. Fiorino

    2011-01-01

    Full Text Available A 10-year-old boy presented with a 3-day history of worsening abdominal pain, fever, emesis and melena. Abdominal ultrasound revealed a right upper quadrant mass that was confirmed by computed tomography angiogram (CTA, which showed an 8 cm well-defined retroperitoneal vascular mass. 123Iodine metaiodobenzylguanidine (123MIBG scan indicated uptake only in the abdominal mass. Subsequent biopsy revealed a paraganglioma that was treated with chemotherapy. This case represents an unusual presentation of a paraganglioma associated with gastrointestinal (GI bleeding and highlights the utility of CTA and 123MIBG in evaluation and treatment.

  17. An unusual case of gastrointestinal bleeding.

    Science.gov (United States)

    Fiorino, Kristin N; Lestini, Brian; Nichols, Kim E; Anupindi, Sudha A; Maqbool, Asim

    2011-01-01

    A 10-year-old boy presented with a 3-day history of worsening abdominal pain, fever, emesis and melena. Abdominal ultrasound revealed a right upper quadrant mass that was confirmed by computed tomography angiogram (CTA), which showed an 8 cm well-defined retroperitoneal vascular mass. (123)Iodine metaiodobenzylguanidine ((123)MIBG) scan indicated uptake only in the abdominal mass. Subsequent biopsy revealed a paraganglioma that was treated with chemotherapy. This case represents an unusual presentation of a paraganglioma associated with gastrointestinal (GI) bleeding and highlights the utility of CTA and (123)MIBG in evaluation and treatment.

  18. An Unusual Case of Gastrointestinal Bleeding

    Science.gov (United States)

    Fiorino, Kristin N.; Lestini, Brian; Nichols, Kim E.; Anupindi, Sudha A.; Maqbool, Asim

    2011-01-01

    A 10-year-old boy presented with a 3-day history of worsening abdominal pain, fever, emesis and melena. Abdominal ultrasound revealed a right upper quadrant mass that was confirmed by computed tomography angiogram (CTA), which showed an 8 cm well-defined retroperitoneal vascular mass. 123Iodine metaiodobenzylguanidine (123MIBG) scan indicated uptake only in the abdominal mass. Subsequent biopsy revealed a paraganglioma that was treated with chemotherapy. This case represents an unusual presentation of a paraganglioma associated with gastrointestinal (GI) bleeding and highlights the utility of CTA and 123MIBG in evaluation and treatment. PMID:22606522

  19. Endoscopic hemostasis state of the art - Nonvariceal bleeding.

    Science.gov (United States)

    Goelder, Stefan Karl; Brueckner, Juliane; Messmann, Helmut

    2016-02-25

    New endoscopic techniques for hemostasis in nonvariceal bleeding were introduced and known methods further improved. Hemospray and Endoclot are two new compounds for topical treatment of bleeding. Initial studies in this area have shown a good hemostatic effect, especially in active large scale oozing bleeding, e.g., tumor bleedings. For further evaluation larger prospective studies comparing the substanced with other methods of endoscopic hemostasis are needed. For localized active arterial bleeding primary injection therapy in the area of ​​bleeding as well as in the four adjacent quadrants offers a good method to reduce bleeding activity. The injection is technically easy to learn and practicable. After bleeding activity is reduced the bleeding source can be localized more clearly for clip application. Today many different through-the-scope (TTS) clips are available. The ability to close and reopen a clip can aid towards good positioning at the bleeding site. Even more important is the rotatability of a clip before application. Often multiple TTS clips are required for secure closure of a bleeding vessel. One model has the ability to use three clips in series without changing the applicator. Severe arterial bleeding from vessels larger than 2 mm is often unmanageable with these conventional methods. Here is the over-the-scope-clip system another newly available method. It is similar to the ligation of esophageal varices and involves aspiration of tissue into a transparent cap before closure of the clip. Thus a greater vascular occlusion pressure can be achieved and larger vessels can be treated endoscopically. Patients with severe arterial bleeding from the upper gastrointestinal tract have a very high rate of recurrence after initial endoscopic treatment. These patients should always be managed in an interdisciplinary team of interventional radiologist and surgeons.

  20. Finite element simulation of structural performance on flexible pavements with stabilized base/treated subbase materials under accelerated loading : tech summary.

    Science.gov (United States)

    2011-12-01

    Accelerated pavement testing (APT) has been increasingly used by state highway agencies in recent years for evaluating pavement : design and performance through applying a simulative heavy vehicular load to the pavement section under controlled fi el...

  1. Summary report on the performance of open graded friction course quieter pavements : I-5 Lynnwood, SR-520 Medina, I-405 Bellevue.

    Science.gov (United States)

    2013-09-01

    This document summarizes the acoustic properties and pavement performance of three asphalt quieter pavement projects. Each of the projects included open graded friction course pavement built with sections of crumb rubber and polymer modified asphalt ...

  2. Inferring pavement layer properties from a moving measurement platform

    DEFF Research Database (Denmark)

    Andersen, Sebastian; Levenberg, Eyal; Andersen, M.B.

    2017-01-01

    was achieved when the correct pavement model and accurate input data were employed. Also, when artificial errors were introduced for assessing sensitivities, only small deviations were generated. Based on these promising outcomes the method will be further studied and developed to support the construction...

  3. Nitrogen Transformations in Three Types of Permeable Pavement

    Science.gov (United States)

    In 2009, USEPA constructed a 0.4-ha (1-ac) parking lot at the Edison Environmental Center in Edison, NJ, that incorporated three different permeable pavement types - permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA). The driving lanes...

  4. Use of noncontact sensors for paving operations on airport pavements

    Science.gov (United States)

    Lenngren, Carl A.

    1999-01-01

    The Swedish National Road Administration has been using a laser range finder system for assessing longitudinal and transversa profiles of pavements for a number of years. The Civil Administration has expressed interest in trying automated methods for surveying airfield runways. Regardless of sampling method, the data re used as input for computer aided design of new pavement surfaces. Typically, the output will consist of tables and maps of where to pave and mill the old pavement surface. Adjusting an old surface to perfectly smooth standards may require continuously changing the new pavement layer thickness. Traditionally, this was often carried out with mechanical devices, usually in direct touch with a wire. Some manufacturers now offer non-contact devices for pavers such as ultra sound sensors as an alternative to the mechanical sensors thus eliminating the need for setting up sires. The method was tested in late 1997 after the output data were converted for a design to be read directly by a paver control unit. A larger test was done in the summer of 1998. The results were promising and the Royal Swedish Fortifications Administration decided to try the method on a taxiway in 1999. The present paper describes some of the experiences obtained with this method and computer controlled equipment in general.

  5. A review on automated pavement distress detection methods

    NARCIS (Netherlands)

    Coenen, Tom B.J.; Golroo, Amir

    2017-01-01

    In recent years, extensive research has been conducted on pavement distress detection. A large part of these studies applied automated methods to capture different distresses. In this paper, a literature review on the distresses and related detection methods are presented. This review also includes

  6. Road Materials and Pavement Design, volume 18, issue 1

    CSIR Research Space (South Africa)

    De Beer, Morris

    2017-01-01

    Full Text Available and Pavement Design Volume 18, 2017 - Issue 1 Editorial Board Page ebi | Published online: 03 Oct 2016 http://dx.doi.org/10.1080/14680629.2016.1244475 Editors-in-Chief Hervé DI BENEDETTO - University of Lyon/ENTPE, Vaulx-en-Velin, France Andrew Charles...

  7. Road Materials and Pavement Design, volume 18, issue 2

    CSIR Research Space (South Africa)

    De Beer, Morris

    2017-03-01

    Full Text Available and Pavement Design Volume 18, 2017 - Issue 2 Editorial Board Page ebi | Published online: 03 Oct 2016 http://dx.doi.org/10.1080/14680629.2016.1244475 Editors-in-Chief Hervé DI BENEDETTO - University of Lyon/ENTPE, Vaulx-en-Velin, France Andrew Charles...

  8. Weed occurrence on pavements in five North European towns

    NARCIS (Netherlands)

    Melander, B.; Holst, N.; Grundy, A.; Kempenaar, C.; Riemens, M.M.; Verschwele, A.; Hansson, D.

    2009-01-01

    Weeds on pavements in urban areas are unwanted mainly because they cause an untidy appearance or sometimes structural damage. Glyphosate has been the principal weed control method for years, but policies in several European towns have changed to lower dependence on herbicides. Instead, less

  9. Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash

    Science.gov (United States)

    Yoshitake, Isamu; Ishida, Takeo; Fukumoto, Sunao

    2015-01-01

    Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone powder was added to improve the early strength; flexural strength at two days reached 3.5 MPa, the minimum strength for traffic service in Japan. The matured fly ash concrete made with a cement content of 200 kg/m3 achieved a flexural strength almost equal to that of the control concrete without fly ash. Additionally, Portland cement made from the tested fly ash concrete was tested to confirm recyclability, with the cement quality meeting the Japanese classification of ordinary Portland cement. Limestone-based recyclable fly ash concrete pavement is, thus, a preferred material in terms of sustainability. PMID:28793518

  10. Common Characteristics of Good and Poorly Performing PCC Pavements

    Science.gov (United States)

    1998-01-01

    This report documents the analysis and findings of a study to identify the site conditions and design/construction features of concrete pavements (JPCP, JRCP, CRCP) that lead to good performance and those that lead to poor performance. Data from Long...

  11. Use of fiber reinforced concrete for concrete pavement slab replacement.

    Science.gov (United States)

    2014-03-01

    Unlike ordinary concrete pavement, replacement concrete slabs need to be open to traffic within 24 hours (sooner in : some cases). Thus, high early-strength concrete is used; however, it frequently cracks prematurely as a result of high : heat of hyd...

  12. Pavement Distress at Road Intersections: A Case Study | Owuama ...

    African Journals Online (AJOL)

    Road intersection represents a major geometric feature of road networks. The rate at which road intersections fail, relative to the entry legs, is exceptionally high hence the need to examine the probable causes. A case was investigated by studying traffic behaviors and pavement conditions at selected intersections.

  13. Classification of mountain bike trails using vehicle-pavement ...

    African Journals Online (AJOL)

    Various mountain bike trails exist in South Africa, but their difficulty ratings are generally unknown. By classifying the trails, risk of injury and uncertainty can be limited as information are provided on the difficulty of the trail. In creating a Trail Classification System (TCS) the principles of Vehicle-Pavement Interaction (V-PI) can ...

  14. Characterization of Bitumen Extracted from used Asphalt Pavement ...

    African Journals Online (AJOL)

    The objectives of the research were principally to characterize extracted bitumen from Used Asphalt Pavement (UAP) on twelve selected roads through the determination of engineering properties (penetration and viscosity) and establishment of appropriate mathematical relationship between principal parameters of the ...

  15. Texas perpetual pavements : experience overview and the way forward.

    Science.gov (United States)

    2010-07-01

    Since 2001, the State of Texas has been designing and constructing perpetual pavements on some of its heavily : trafficked highways where the expected 20-year truck-traffic estimate of 18 kip ESALs is in excess of 30 million. To : date, there are 10 ...

  16. Evaluation of the life shortening of flexible pavements | Bavandpour ...

    African Journals Online (AJOL)

    One of the reasons of life shortening of pavements operation is designing regardless of their administrative facts. The amount of transferred load between the layers depends on various factors such as the degree of adhesion and internal friction between the layers. If these layers limit by using proper bonding and sufficient ...

  17. Forensic Investigation of Premature Failure of a Roadway Pavement ...

    African Journals Online (AJOL)

    Tests conducted on the pavement layers of the failed road included moisture content, particle size distribution of soil samples, Atterberg limit tests, in-situ density and dynamic cone penetrometer (DCP) tests. An empirical equation from published literature was used to compute the California bearing ratio (CBR) of various ...

  18. ANALYSES OF THE INFLUENCE OF MATERIAL CHARACTERISTICS ON PAVEMENT DESIGN

    Directory of Open Access Journals (Sweden)

    Nino Vukobratović

    2017-01-01

    Full Text Available Currently, only empirical design methods are used in the application of well-known standards for pavement structure design. Given this fact, it is assumed that material characteristics correspond to average quality materials. Thus, the aim of this study included examining the influence of material characteristics on pavement design analyzing changes in the cement bound base layer (CBL characteristics with respect to the occurrence of cracks and changes in the asphalt layer given typical seasonal changes. The study involved varying CBL modulus as 15 GPa, 10 GPa, and 5 GPa. Additionally, the moduli of asphalt layers were varied from 6 MPa to 2 MPa to simulate real conditions in pavement structure life. The analyses indicated that there was a significant difference in pavement behavior with respect to changes in material characteristics. Given these significant differences, it is extremely important to properly define material characteristics while using empirical design methods. Proper material characterization combined with the utilization of empirical and analytical methods increases the possibility of reducing layers thickness to design cost-effective structures.

  19. Experimental continuously reinforced concrete pavement parameterization using nondestructive methods

    Directory of Open Access Journals (Sweden)

    L. S. Salles

    Full Text Available ABSTRACT Four continuously reinforced concrete pavement (CRCP sections were built at the University of São Paulo campus in order to analyze the pavement performance in a tropical environment. The sections short length coupled with particular project aspects made the experimental CRCP cracking be different from the traditional CRCP one. After three years of construction, a series of nondestructive testing were performed - Falling Weight Deflectometer (FWD loadings - to verify and to parameterize the pavement structural condition based on two main properties: the elasticity modulus of concrete (E and the modulus of subgrade reaction (k. These properties estimation was obtained through the matching process between real and EverFE simulated basins with the load at the slab center, between two consecutive cracks. The backcalculation results show that the lack of anchorage at the sections end decreases the E and k values and that the longitudinal reinforcement percentage provides additional stiffness to the pavement. Additionally, FWD loadings tangential to the cracks allowed the load transfer efficiency (LTE estimation determination across cracks. The LTE resulted in values above 90 % for all cracks.

  20. Investigation of causes of failures of flexible pavements: a case ...

    African Journals Online (AJOL)

    The visual inspection of the pavement showed that due to the hardening of the bitumen and overloading, cracks and potholes were very common for the whole stretch of the road. Axle load data revealed that, there has been a tendency to exceed the maximum allowed axle load limits, especially until 19th august, 1999, after ...

  1. Optimisation of the Crack Pattern in Continuously Reinforced Concrete Pavements

    NARCIS (Netherlands)

    Ren, D.

    2015-01-01

    Recent field investigations on several new Continuously Reinforced Concrete Pavements (CRCP) in Belgium indicate that its crack pattern is characterized by low mean crack spacing along with a high percentage of clusters of closely spaced cracks. Field surveys also indicate that it is difficult to

  2. Evaluating Pavement Cracks with Bidimensional Empirical Mode Decomposition

    Directory of Open Access Journals (Sweden)

    Nii Attoh-Okine

    2008-05-01

    Full Text Available Crack evaluation is essential for effective classification of pavement cracks. Digital images of pavement cracks have been analyzed using techniques such as fuzzy set theory and neural networks. Bidimensional empirical mode decomposition (BEMD, a new image analysis method recently developed, can potentially be used for pavement crack evaluation. BEMD is an extension of the empirical mode decomposition (EMD, which can decompose nonlinear and nonstationary signals into basis functions called intrinsic mode functions (IMFs. IMFs are monocomponent functions that have well-defined instantaneous frequencies. EMD is a sifting process that is nonparametric and data driven; it does not depend on an a priori basis set. It is able to remove noise from signals without complicated convolution processes. BEMD decomposes an image into two-dimensional IMFs. The present paper explores pavement crack detection using BEMD together with the Sobel edge detector. A number of images are filtered with BEMD to remove noise, and the residual image analyzed with the Sobel edge detector for crack detection. The results are compared with results from the Canny edge detector, which uses a Gaussian filter for image smoothing before performing edge detection. The objective is to qualitatively explore how well BEMD is able to smooth an image for more effective edge detection with the Sobel method.

  3. Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash

    Directory of Open Access Journals (Sweden)

    Isamu Yoshitake

    2015-08-01

    Full Text Available Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone powder was added to improve the early strength; flexural strength at two days reached 3.5 MPa, the minimum strength for traffic service in Japan. The matured fly ash concrete made with a cement content of 200 kg/m3 achieved a flexural strength almost equal to that of the control concrete without fly ash. Additionally, Portland cement made from the tested fly ash concrete was tested to confirm recyclability, with the cement quality meeting the Japanese classification of ordinary Portland cement. Limestone-based recyclable fly ash concrete pavement is, thus, a preferred material in terms of sustainability.

  4. Fatigue and rutting strain analysis of flexible pavements designed ...

    African Journals Online (AJOL)

    ELO

    elastic analysis are that; i) The pavement structure is regarded as a linear elastic multilayered system in which the stress-strain solution of the material are characterized by the Young's modulus of. Elasticity E and poison's ratio µ. ii) Each layer has a finite thickness h except the lower. Ekwulo and Eme 413. P. µ1 = 0.5, h1, E1.

  5. Representative volume element of asphalt pavement for electromagnetic measurements

    Directory of Open Access Journals (Sweden)

    Terhi Pellinen

    2015-02-01

    Full Text Available The motivation for this study was to investigate the representative volume element (RVE needed to correlate the nondestructive electromagnetic (EM measurements with the conventional destructive asphalt pavement quality control measurements. A large pavement rehabilitation contract was used as the test site for the experiment. Pavement cores were drilled from the same locations where the stationary and continuous Ground Penetrating Radar (GPR measurements were obtained. Laboratory measurements included testing the bulk density of cores using two methods, the surface-saturated dry method and determining bulk density by dimensions. Also, Vector Network Analyzer (VNA and the through specimen transmission configuration were employed at microwave frequencies to measure the reference dielectric constant of cores using two different footprint areas and therefore volume elements. The RVE for EM measurements turns out to be frequency dependent; therefore in addition to being dependent on asphalt mixture type and method of obtaining bulk density, it is dependent on the resolution of the EM method used. Then, although the average bulk property results agreed with theoretical formulations of higher core air void content giving a lower dielectric constant, for the individual cores there was no correlation for the VNA measurements because the volume element seizes deviated. Similarly, GPR technique was unable to capture the spatial variation of pavement air voids measured from the 150-mm drill cores. More research is needed to determine the usable RVE for asphalt.

  6. Evaluation of concrete inlay for continuously reinforced concrete pavement rehabilitation.

    Science.gov (United States)

    2010-06-01

    In 1996, WisDOT constructed a concrete inlay test section on I43 in Manitowoc County. The existing pavement was CRCP constructed in 1978 and was badly deteriorated with punchouts. In the area of the 2777foot test section, the existing paveme...

  7. Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash.

    Science.gov (United States)

    Yoshitake, Isamu; Ishida, Takeo; Fukumoto, Sunao

    2015-08-21

    Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone powder was added to improve the early strength; flexural strength at two days reached 3.5 MPa, the minimum strength for traffic service in Japan. The matured fly ash concrete made with a cement content of 200 kg/m3 achieved a flexural strength almost equal to that of the control concrete without fly ash. Additionally, Portland cement made from the tested fly ash concrete was tested to confirm recyclability, with the cement quality meeting the Japanese classification of ordinary Portland cement. Limestone-based recyclable fly ash concrete pavement is, thus, a preferred material in terms of sustainability.

  8. High-volume recycled materials for sustainable pavement construction.

    Science.gov (United States)

    2017-05-01

    The main objective of this research is to evaluate the feasibility of using high-volume recycled materials for concrete production in rigid pavement. The goal was to replace 50% of the solids with recycled materials and industrial by-products. The pe...

  9. Fatigue and rutting strain analysis of flexible pavements designed ...

    African Journals Online (AJOL)

    The layered elastic analysis of pavements designed using three known CBR methods; the Asphalt Institute, the National Crushed Stone Association and the Nigerian CBR methods were carried out to evaluate their fatigue strain and rutting deformation characteristics. The elastic properties of the materials were determined.

  10. Road Materials and Pavement Design, 30 May 2017

    CSIR Research Space (South Africa)

    De Beer, Morris

    2017-01-01

    Full Text Available and Pavement Design Vol. 18, Issue 1 2017 http://www.tandfonline.com/toc/trmp20/18/1?nav=tocList Editorial board EDITORS-IN-CHIEF Hervé Di Benedetto - University of Lyon / ENTPE, Vaulx-en-Velin, France Andrew Charles Collop - De Montfort University...

  11. Performances of Metal Concentrations from Three Permeable Pavement Infiltrates

    Science.gov (United States)

    The U.S. Environmental Protection Agency constructed a 4000-m2 parking lot in Edison, New Jersey in 2009. The parking lot is surfaced with three permeable pavements [permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA)]. Samples of each p...

  12. PROTOTYPE WEB-BASED EXPERT SYSTEM FOR FLEXIBLE PAVEMENT MAINTENANCE

    Directory of Open Access Journals (Sweden)

    ABDALRHMAN MILAD

    2017-11-01

    Full Text Available The paper describes the development of a prototype web-based expert knowledge system that can be used to maintain flexible pavement within a tropical region. This prototype system provides the advantages of using existing web-based expert system technology. Currently, deterioration of asphalt pavement layers is one of the biggest problems in Malaysia and requires maintenance to ensure that the roads remain open and able to guarantee the regularity, punctuality, and safety of all transport services. According to this process, the knowledge collection that has acquired and the date concerning to domain expert system of the development web-based system was launched with knowledge representation IF and THEN rules and coded by PHP programming. The web pages that support the user interface are created using a framework consisting of HTML, CSS, and J-Query. The prototype web-based expert system uses the knowledge of a pavement maintenance expert, or a specialist in pavement problem remediation, to emulate a portion of their professional reasoning abilities, which it can then use to assist with the maintenance of existing roads and enhance the efficiency and accuracy of the professional engineers tasked with the assessment of all available remedies. Thus, the system increases the performance level of the engineers in analysing, discerning and customising the information that will assist decision makers throughout the project, so the probability that the right decision and treatment are implemented at the right time is increased.

  13. sensitivity analysis on flexible road pavement life cycle cost model

    African Journals Online (AJOL)

    user

    Sensitivity analysis is a tool used in the assessment of a model's performance. This study examined the application of sensitivity analysis on a developed flexible pavement life cycle cost model using varying discount rate. The study area is Effurun, Uvwie Local Government Area of Delta State of Nigeria. In order to ...

  14. Measuring Carbon Footprint of Flexible Pavement Construction Project in Indonesia

    Science.gov (United States)

    Hatmoko, Jati Utomo Dwi; Hidayat, Arif; Setiawati, Apsari; Prasetyo, Stefanus Catur Adi

    2018-02-01

    Road infrastructure in Indonesia is mainly dominated by flexible pavement type. Its construction process, however, has raised concerns in terms of its environment impacts. This study aims to track and measure the carbon footprint of flexible pavement. The objectives are to map the construction process in relation to greenhouse gas (GHG) emissions, to quantify them in terms of carbon dioxide equivalents (CO2e) as generated by the process of production and transportation of raw materials, and the operation of plant off-site and on-site project. Data collection was done by having site observations and interviews with project stakeholders. The results show a total emissions of 70.888 tonnes CO2e, consisting of 34.248 tonnes CO2e (48.31%) off-site activities and 36.640 tonnes CO2e (51.687%) on-site activities. The two highest CO2e emissions were generated by the use of plant for asphalt concrete laying activities accounted 34.827 tonnes CO2e (49.130%), and material transportation accounted 24.921 (35.155%). These findings provide a new perspective of the carbon footprint in flexible pavement and suggest the urgent need for the use of more efficient and environmentally friendly plant in construction process as it shows the most significant contribution on the CO2e. This study provides valuable understanding on the environmental impact of typical flexible pavement projects in Indonesia, and further can be used for developing green road framework.

  15. Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Bryer, P.J.; Scoggins, M.; McClintock, N.L. [Lamar University, Beaumont, TX (United States). Dept. of Biology

    2010-05-15

    Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, & 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P < 0.0001) between treatments in addition to specific taxa responses, displaying a clear negative relationship with the amount of coal-tar sealant flake. These results support the hypothesis that coal-tar pavement sealants contain bioavailable PAHs that may harm aquatic environments.

  16. Effects of Interlocking and Supporting Conditions on Concrete Block Pavements

    Science.gov (United States)

    Mahapatra, Geetimukta; Kalita, Kuldeep

    2018-02-01

    Concrete Block Paving (CBP) is widely used as wearing course in flexible pavements, preferably under light and medium vehicular loadings. Construction of CBP at site is quick and easy in quality control. Usually, flexible pavement design philosophy is followed in CBP construction, though it is structurally different in terms of small block elements with high strength concrete and their interlocking aspects, frequent joints and discontinuity, restrained edge etc. Analytical solution for such group action of concrete blocks under loading in a three dimensional multilayer structure is complex and thus, the need of conducting experimental studies is necessitated for extensive understanding of the load—deformation characteristics and behavior of concrete blocks in pavement. The present paper focuses on the experimental studies for load transfer characteristics of CBP under different interlocking and supporting conditions. It is observed that both interlocking and supporting conditions affect significantly on the load transfer behavior in CBP structures. Coro-lock block exhibits better performance in terms of load carrying capacity and distortion behavior under static loads. Plate load tests are performed over subgrade, granular sub-base (GSB), CBP with and without GSB using different block shapes. For an example case, the comparison of CBP with conventional flexible pavement section is also presented and it is found that CBP provides considerable benefit in terms of construction cost of the road structure.

  17. Cost-benefit analysis - noise barriers and quieter pavements

    Science.gov (United States)

    2014-01-01

    This report presents the results of one TQA Follow-up event, a workshop titled Cost Benefit Analysis Noise Barriers and Quieter Pavements, which was organized by the DOT Volpe Center and hosted by the NAE at the National Academies Keck Center, Wa...

  18. Effect Analysis of Vehicle System Parameters on Dynamic Response of Pavement

    Directory of Open Access Journals (Sweden)

    Rong-xia Xia

    2015-01-01

    Full Text Available In order to study the damage of a semirigid pavement under vehicle loads with varied parameters, the random dynamic loads applied on the pavement by a running vehicle were computed with two degrees of freedom, quarter-vehicle model, and then a three-dimensional finite element analysis model of semirigid asphalt pavement was established. With the peak stress index of each pavement layer, the effect of varied vehicle parameters on pavement response was studied. The results indicated that the stress wave frequency of each pavement layer was similar to that of the dynamic random load, and, with increased pavement depth, the wave effect decreased. The pavement response increased with increased suspension stiffness and tire stiffness and decreased with increased suspension damping and tire damping. Furthermore, compared to the stiffness, the response variation induced by the damping was orders of magnitude lower. Compared with the traditional time response analysis method, the peak response analysis of the pavement structure was more scientific, rational, and intuitive, which could be useful for the study of vehicle-pavement interaction and road damage.

  19. An assessment of the skid resistance effect on traffic safety under wet-pavement conditions.

    Science.gov (United States)

    Pardillo Mayora, José M; Jurado Piña, Rafael

    2009-07-01

    Pavement-tire friction provides the grip that is required for maintaining vehicle control and for stopping in emergency situations. Statistically significant negative correlations of skid resistance values and wet-pavement accident rates have been found in previous research. Skid resistance measured with SCRIM and crash data from over 1750km of two-lane rural roads in the Spanish National Road System were analyzed to determine the influence of pavement conditions on safety and to assess the effects of improving pavement friction on safety. Both wet- and dry-pavement crash rates presented a decreasing trend as skid resistance values increased. Thresholds in SCRIM coefficient values associated with significant decreases in wet-pavement crash rates were determined. Pavement friction improvement schemes were found to yield significant reductions in wet-pavement crash rates averaging 68%. The results confirm the importance of maintaining adequate levels of pavement friction to safeguard traffic safety as well as the potential of pavement friction improvement schemes to achieve significant crash reductions.

  20. Nutrient infiltrate concentrations from three permeable pavement types.

    Science.gov (United States)

    Brown, Robert A; Borst, Michael

    2015-12-01

    While permeable pavement is increasingly being used to control stormwater runoff, field-based, side-by-side investigations on the effects different pavement types have on nutrient concentrations present in stormwater runoff are limited. In 2009, the U.S. EPA constructed a 0.4-ha parking lot in Edison, New Jersey, that incorporated permeable interlocking concrete pavement (PICP), pervious concrete (PC), and porous asphalt (PA). Each permeable pavement type has four, 54.9-m(2), lined sections that direct all infiltrate into 5.7-m(3) tanks enabling complete volume collection and sampling. This paper highlights the results from a 12-month period when samples were collected from 13 rainfall/runoff events and analyzed for nitrogen species, orthophosphate, and organic carbon. Differences in infiltrate concentrations among the three permeable pavement types were assessed and compared with concentrations in rainwater samples and impervious asphalt runoff samples, which were collected as controls. Contrary to expectations based on the literature, the PA infiltrate had significantly larger total nitrogen (TN) concentrations than runoff and infiltrate from the other two permeable pavement types, indicating that nitrogen leached from materials in the PA strata. There was no significant difference in TN concentration between runoff and infiltrate from either PICP or PC, but TN in runoff was significantly larger than in the rainwater, suggesting meaningful inter-event dry deposition. Similar to other permeable pavement studies, nitrate was the dominant nitrogen species in the infiltrate. The PA infiltrate had significantly larger nitrite and ammonia concentrations than PICP and PC, and this was presumably linked to unexpectedly high pH in the PA infiltrate that greatly exceeded the optimal pH range for nitrifying bacteria. Contrary to the nitrogen results, the PA infiltrate had significantly smaller orthophosphate concentrations than in rainwater, runoff, and infiltrate from PICP