bluuebunny/crossref_metadata_2025 huggingface dataset:
Aconselhamento em contracepção: grupo de capacitação de profissionais médicos do Programa de Saúde da Família
Authors: Santos Manoel Antônio dos , Vieira Elisabeth Meloni
Published: October 2008

Analisam-se as potencialidades de uma intervenção em grupo com o propósito de capacitar médicos residentes do Programa de Saúde da Família (PSF) para aconselhamento em contracepção. Ancorados no pressuposto da incorporação da sexualidade nessa área, os autores trabalharam com estratégias que se destinam a sensibilizar os profissionais para ouvir as questões sexuais que estão subentendidas na orientação para a contracepção. Foi utilizada metodologia qualitativa. O corpus foi construído com base na técnica de observação participante e consistiu em relatos provenientes da transcrição das notas do diário de campo da coordenadora do grupo. Observou-se que a possibilidade de compartilhar saber, numa relação de horizontalidade, favoreceu a revisão de crenças e valores que sustentam a prática médica, ajudando profissionais a transcenderem uma visão tecnicista da orientação em contracepção.
Educação em serviço para profissionais de saúde do Serviço de Atendimento Móvel de Urgência (SAMU): relato da experiência de Porto Alegre-RS
Authors: Ciconet Rosane Mortari , Marques Giselda Quintana , Lima Maria Alice Dias da Silva
Published: October 2008

Relata-se a experiência realizada no Serviço de Atendimento Móvel de Urgência Samu 192, da Secretaria Municipal de Saúde de Porto Alegre - RS, quanto ao trabalho desenvolvido pelo Núcleo de Educação Permanente em Urgências. Consta das principais necessidades e dos principais avanços encontrados no desenvolvimento das atividades, apresentando uma reflexão crítica do processo desenvolvido. Reconhece-se que implantar e manter processos de Educação Permanente em Urgências junto aos Samu é de fundamental relevância para a qualificação dos serviços, entretanto, registram-se as dificuldades na sua execução, especialmente devidas à forma da organização do trabalho no componente pré-hospitalar móvel. Conclui-se que investir na educação incorporada à rotina de trabalho como um processo efetivo, contínuo e ajustado às necessidades do cotidiano e da evolução da estratégia constitui prioridade de gestão e de avaliação de sua qualidade.
Da tristeza à depressão: a transformação de um mal-estar em adoecimento no trabalho
Authors: Brant Luiz Carlos , Minayo-Gomez Carlos
Published: October 2008

No trabalho pós-industrial, a tristeza tornou-se um tabu. Em contextos de competitividade, trabalhar e viver têm deixado as pessoas tristes. Buscamos reconstruir e compreender a trajetória que vai da expressão da tristeza ao diagnóstico de depressão em um estudo qualitativo, tendo como método de análise a hermenêutica-dialética. Entrevistamos 13 trabalhadores, 13 gestores e oito técnicos da saúde de uma empresa. Realizamos, também, análise documental de house organs. Constatamos que o adoecimento se iniciava quando gestores encaminhavam pessoas tristes para o setor médico, onde eram tratadas e medicalizadas como depressivas. Algumas informações entre gestores e técnicos da saúde revelavam deslizes éticos. O diagnóstico de depressão eximia a empresa da responsabilidade na configuração daquela vida triste. Concluímos que esse diagnóstico constitui uma forma de não ressignificar a tristeza e sua relação com o trabalho. É uma ferida ética que implica excluir aquele que não apresenta semblante de bem-estar.
Giant cystic malignant pheochromocytoma invading right hepatic lobe: report on two cases
Authors: Costa Sergio Renato Pais , Cabral Nivaldo Marques , Abhrão Ademir Torres , Costa Ricardo Borges da , Silva Lilian Mary da , Lupinacci Renato Arioni
Published: October 2008

CONTEXT: Cystic pheochromocytomas are uncommon neuroendocrine tumors that originate from the adrenal medulla. Differing from the more frequent solid pheochromocytomas, which produce catecholamines and present adrenergic syndrome, cystic pheochromocytomas may not produce these. Their symptoms are generally associated with an abdominal mass or even pain, particularly if the mass attains large dimensions. Similarly, radiological diagnosis may also be difficult. Right-side lesions may be confounded with cystic hepatic tumors or even retroperitoneal sarcomas with cystic areas, using radiological methods. Sometimes, there may be a preoperative diagnosis of malignancy. Invasion of organs in this region (i.e. liver or kidney), or even the presence of a large retroperitoneal mass (of uncertain origin) with which multiple organs are involved, may be indicative of malignant origin. CASE REPORT: Two cases of giant cystic pheochromocytoma that invaded the right hepatic lobe are described. These presented as abdominal masses. Both cases were malignant. They were treated by radical right nephrectomy plus right hepatectomy.
Round pneumonia: a rare condition mimicking bronchogenic carcinoma. Case report and review of the literature
Authors: Camargo José Jesus de Peixoto , Camargo Spencer Marcantonio , Machuca Tiago Noguchi , Perin Fabíola Adélia
Published: October 2008

CONTEXT: Round pneumonia is a condition usually described in children, with few reports addressing adult patients. It is an oval-shaped consolidation that, due to its radiological appearance, simulates bronchogenic carcinoma. Its evolution tends to be benign, although diagnostic dilemmas have sometimes required exploratory thoracotomy. Deaths caused by this condition have even been reported. To the best of our knowledge, there have been 31 previous cases of round pneumonia in adults reported in the English and Portuguese-language literature, of which only one was completely asymptomatic. CASE REPORT: The case of a 54-year-old female patient presenting a lung mass found on routine imaging evaluation is reported. Respiratory symptoms and signs were absent, but the patient had a significant history of smoking. Her physical examination gave normal results. On chest radiographs, a mass located in the middle third of the right lung was observed. Three weeks after the initial evaluation, the patient was admitted for a complete evaluation and for staging of a pulmonary malignancy, but repeated chest radiographs showed complete resolution.
Spatial variability: drained and undrained deviatoric load response
Authors: Kim H.-K. , Santamarina J. C.
Published: October 2008

Geotechnical properties vary in space. Geostatistical parameters such as the mean, the standard deviation and the correlation length are characteristic for each sediment and formation history. The effects of spatial variability on the drained and undrained shear response of soils are investigated using numerical parametric studies where multiple realisations are tested for selected geostatistical parameters. Results show that the mean undrained shear strength decreases as spatial variability and correlation length increase. Spatial variability prompts strain localisation along neighbouring weak zones under both drained and undrained loading. Heterogeneous contractive media show internal homogenisation during drained deviatoric loading, and the drained shear resistance evolves towards the critical state; media with higher variability and longer correlation length require higher strain to attain internal homogenisation. Anisotropy in spatial correlation causes anisotropy in shear strength. An intermediate drainage condition emerges in spatially varying media whereby local drainage may develop during globally undrained shear; local drainage affects the load–deformation response.
Modelling the landfill process using GasSim2
Authors: Clewes H. , Fuggles E. , Davies S. , Gregory R. G.
Published: October 2008

The prediction of landfill gas generation is an important exercise for both operators and regulators of landfill sites. The GasSim2 model, developed for this purpose by Golder Associates (UK) Ltd on behalf of the Environment Agency, is used to predict gas generation and subsequent emissions to air and land in order to assess whether emissions exceed acceptable limits. A number of other models for the prediction of landfill processes exist, and they have evolved significantly over the last decade. In order to compare individual models' strengths and weaknesses and therefore enable further development, a formal framework was designed by researchers at Southampton University. A challenge was set to modellers to predict the performance of a laboratory experiment on biodegradable waste. The data provided, including waste composition, cellulose and hemicellulose content, leachate recirculation and experimental layout, were manipulated to fit into GasSim2. A number of difficulties were experienced in modelling, including scaling the laboratory experiment to the required scale of the model, categorisation of the waste stream and the length of the model timestep. Model results indicate a potential for gas production of 17·7–47·6 m3/t dry waste per year initially, decreasing over time.
Ecological consequences of the Three Gorges Dam: insularization affects foraging behavior and dynamics of rodent populations
Authors: Wang Jianzhu , Huang Jianhui , Wu Jianguo , Han Xingguo , Lin Guanghui
Published: October 2008

A number of permanent and seasonal islands will be formed when the world's largest dam, China's Three Gorges Dam, begins to operate at full capacity in 2009. The possible effects of this large‐scale habitat insularization on biodiversity and ecosystem processes have attracted considerable attention from scientists around the globe. We investigated the species composition and distribution of rodent populations at two geographic locations in the Three Gorges Reservoir Area through field surveys and determined the dietary composition of dominant rodent species using stable isotope techniques. Our results show that the total rodent density on the islands was significantly higher than that of mainland areas. Stable isotope analysis revealed that the dietary composition of rodents was more diverse on islands than at nearby mainland sites. Moreover, the island populations had greater overlap in food sources than did the mainland populations, suggesting more intense competition for food in the newly insularized habitats. Thus, habitat fragmentation due to the construction of the Three Gorges Dam may substantially increase intra‐ and interspecific competition among local rodent populations, leading to further changes in species composition and biodiversity.
Innovative assessment tools to improve water quality and watershed management in farming areas
Authors: Merot Philippe , Aurousseau Pierre , Gascuel-Odoux Chantal , Durand Patrick
Published: October 2008

A lot of initiatives for improving water quality have been developed over the last 15 y in Brittany in response to degradation induced by intensive farming and under the pressure of European policy and environmental organizations. This has involved the partnerships of farmer organizations, organizations in charge of rural affairs, research and formation institutes, and environmental nongovernmental organizations. In this paper, we present 2 complementary aspects of an original, and possibly efficient, water policy within the framework of water management in a medium-sized watershed, including 1) development of new methods of diagnostic and decision support based on participative approaches and 2) development of new methods to assess the current status and effect of alternative scenarios, taking into account the complexity of a system with strong agricultural and hydrological variability and a relatively long response time. The 1st series of methods, which deals with the buffering capacity of landscape structures, is close to a social learning approach; the 2nd illustrates the importance, for policy makers, of a precisely defined protocol for data monitoring and analysis and of the use of spatially distributed and dynamic models when water policy is based on an obligation of results. In spite of the coexistence of all the necessary constituents of a coherent policy, it seems difficult to build. The state of current water quality illustrates the importance and limitations of incentive policy.
Letter: The Bailout and What Next
Authors: Ho Lok Sang
Published: October 2008

Lok Sang Ho argues that the bailout plan merely buys time. Other policies to stop the hemorrhage stemming from the housing market and to restore interest in home-buying in the short term are necessary.
Herd Behavior and Contagion in Financial Markets
Authors: Cipriani Marco , Guarino Antonio
Published: October 2008

We study a sequential trading financial market where there are gains from trade, that is, where informed traders have heterogeneous private values. We show that an informational cascade (i.e., a complete blockage of information) arises and prices fail to aggregate information dispersed among traders. During an informational cascade, all traders with the same preferences choose the same action, following the market (herding) or going against it (contrarianism). We also study financial contagion by extending our model to a two-asset economy. We show that informational cascades in one market can be generated by informational spillovers from the other. Such spillovers have pathological consequences, generating long-lasting misalignments between prices and fundamentals.
Ex Post Private Information and Monopolistic Screening
Authors: Krahmer Daniel , Strausz Roland
Published: October 2008

This paper investigates how additional ex post private information by the agent affects the equilibrium outcome of the monopolistic screening model. In general, the principal always weakly benefits when the agent receives additional private information after the contracting stage. Instead, both the agent's equilibrium payoffs and allocative efficiency may, due to the principal's concerns about information rents, increase or decrease. Moreover, we obtain the result that optimal contracts may involve lying offtheequilibrium path and show that this exacerbates bunching in the monopolistic screening problem.
Inhibition of Dipeptidyl Peptidase-4 by Vildagliptin During Glucagon-Like Peptide 1 Infusion Increases Liver Glucose Uptake in the Conscious Dog
Authors: Edgerton Dale S. , Johnson Kathryn M.S. , Neal Doss W. , Scott Melanie , Hobbs Charles H. , Zhang Xia , Duttaroy Alokesh , Cherrington Alan D.
Published: October 2008

OBJECTIVE—This study investigated the acute effects of treatment with vildagliptin on dipeptidyl peptidase-4 (DPP-4) activity, glucagon-like peptide 1 (GLP-1) concentration, pancreatic hormone levels, and glucose metabolism. The primary aims were to determine the effects of DPP-4 inhibition on GLP-1 clearance and on hepatic glucose uptake.

RESEARCH DESIGN AND METHODS—Fasted conscious dogs were studied in the presence (n = 6) or absence (control, n = 6) of oral vildagliptin (1 mg/kg). In both groups, GLP-1 was infused into the portal vein (1 pmol · kg−1 · min−1) for 240 min. During the same time, glucose was delivered into the portal vein at 4 mg · kg−1 · min−1 and into a peripheral vein at a variable rate to maintain the arterial plasma glucose level at 160 mg/dl.

RESULTS—Vildagliptin fully inhibited DPP-4 over the 4-h experimental period. GLP-1 concentrations were increased in the vildagliptin-treated group (50 ± 3 vs. 85 ± 7 pmol/l in the portal vein in control and vildagliptin-treated dogs, respectively; P < 0.05) as a result of a 40% decrease in GLP-1 clearance (38 ± 5 and 22 ± 2 ml · kg−1 · min−1, respectively; P < 0.05). Although hepatic insulin and glucagon levels were not significantly altered, there was a tendency for plasma insulin to be greater (hepatic levels were 73 ± 10 vs. 88 ± 15 μU/ml, respectively). During vildagliptin treatment, net hepatic glucose uptake was threefold greater than in the control group. This effect was greater than that predicted by the change in insulin.

CONCLUSIONS—Vildagliptin fully inhibited DPP-4 activity, reduced GLP-1 clearance by 40%, and increased hepatic glucose disposal by means beyond the effects of GLP-1 on insulin and glucagon secretion.
The Darkening Cloud of Diabetes
Authors: Eurich Dean T. , Gamble John-Michael , Simpson Scot H. , Johnson Jeffrey A.
Published: October 2008

OBJECTIVE—We aimed to evaluate the changes in cardiovascular-related health care utilization (drug therapies, hospitalizations) and mortality for the diabetic population during a 9-year period in Saskatchewan, Canada.

RESEARCH DESIGN AND METHODS—We identified annual diabetes prevalence rates for people aged ≥30 years between 1993 and 2001 from the administrative databases of Saskatchewan Health. Annual rates of evidence-based drug therapies (antihypertensives, ACE inhibitors, β-blockers, calcium channel blockers, 3-hydroxy-3-metaglutaryl coenzyme A reductase inhibitors [statins]), hospitalizations for cerebrovascular and cardiac events, and all-cause mortality were estimated. Rates were direct age and sex standardized using the 2001 Canadian population, and trends over time were assessed using Joinpoint regression.

RESULTS—From 1993 to 2001, diabetes prevalence increased 34% (4.7–6.5%, P < 0.001) with the highest rates in men and those aged ≥65 years. The rate of increase in diabetes prevalence appeared to slow in those aged <65 years (P < 0.01 for trend). Significant increased use of evidence-based drug therapies was observed (41% increase in antihypertensive agents, 97% increase in ACE inhibitors, 223% increase in statin therapies; all P < 0.05 for trend). During this period, both cerebrovascular and cardiac-related hospitalizations declined by 36% (9.5 vs. 6.1 per 1,000) and 19% (38.0 vs. 30.6 per 1,000) (P < 0.05 for trends), respectively, with similar reductions regardless of sex. No change in all-cause mortality was observed (17.7 vs. 17.8 deaths per 1,000; P > 0.05).

CONCLUSIONS—During our period of study, there was an increase in the utilization of evidenced-based drug therapies in people with diabetes and reductions in cardiovascular-related hospitalizations. Despite this, we observed no change in all-cause mortality.
Asymptotic expressions for remainder terms of some quadrature rules
Authors: Ujević Nenad , Bilić Nataša
Published: October 2008

Asymptotic expressions for remainder terms of the mid-point, trapezoid and Simpson’s rules are given. Corresponding formulas with finite sums are also given.
A general construction of nonseparable multivariate orthonormal wavelet bases
Authors: Karoui Abderrazek
Published: October 2008

The construction of nonseparable and compactly supported orthonormal wavelet bases of L
2(R
n); n ≥ 2, is still a challenging and an open research problem. In this paper, we provide a special method for the construction of such wavelet bases. The wavelets constructed by this method are dyadic wavelets. Also, we show that our proposed method can be adapted for an eventual construction of multidimensional orthogonal multiwavelet matrix masks, candidates for generating multidimensional multiwavelet bases.
New Challenges in Dynamical Systems: The Networked Case
Authors: Bauer Peter
Published: October 2008

New Challenges in Dynamical Systems: The Networked Case

This paper describes new technical challenges that arise from networking dynamical systems. In particular, the paper takes a look at the underlying phenomena and the resulting modeling problems that arise in such systems. Special emphasis is placed on the problem of synchronization, since this problem has not received as much attention in the literature as the phenomena of packet drop, delays, etc. The paper then discusses challenges arising in prominent areas such as congestion control, sensor networks, as well as vehicle networks and swarms.
New Self-Checking Booth Multipliers
Authors: Hunger Marc , Marienfeld Daniel
Published: October 2008

New Self-Checking Booth Multipliers

This work presents the first self-checking Booth-3 multiplier and a new self-checking Booth-2 multiplier using parity prediction. We propose a method which combines error-detection of Booth-3 (or Booth-2) decoder cells and parity prediction. Additionally, code disjointness is ensured by reusing logic for partial product generation. Parity prediction is applied to a carry-save-adder with the standard sign-bit extension. In this adder almost all cells have odd fanouts and faults are detected by the parity. Only one adder cell has an even fanout in the case of Booth-3 multiplication. Especially, for even-number Booth-2 multipliers parity prediction becomes efficient. Since that prediction slightly differs from previous work which describes CSA-folded adders, formulas to predict the parity are developed here. The proposed multipliers are compared experimentally with existing solutions. Only 102% of the area of Booth-2 without error detection is needed for the self-checking Booth-3 multiplier.
Address Sequences and Backgrounds with Different Hamming Distances for Multiple Run March Tests
Authors: Yarmolik Svetlana
Published: October 2008

Address Sequences and Backgrounds with Different Hamming Distances for Multiple Run March Tests

It is widely known that pattern sensitive faults are the most difficult faults to detect during the RAM testing process. One of the techniques which can be used for effective detection of this kind of faults is the multi-background test technique. According to this technique, multiple-run memory test execution is done. In this case, to achieve a high fault coverage, the structure of the consecutive memory backgrounds and the address sequence are very important. This paper defines requirements which have to be taken into account in the background and address sequence selection process. A set of backgrounds which satisfied those requirements guarantee us to achieve a very high fault coverage for multi-background memory testing.
On the Development of SCILAB Compatible Software for the Analysis and Control of Repetitive Processes
Authors: Hładowski Łukasz , Cichy Błażej , Gałkowski Krzysztof , Rogers Eric
Published: October 2008

On the Development of SCILAB Compatible Software for the Analysis and Control of Repetitive Processes

In this paper further results on the development of a Scilab compatible software package for the analysis and control of repetitive processes is described. The core of the package consists of a simulation tool which enables the user to inspect the response of a given example to an input, design a control law for stability and/or performance, and also simulate the response of a controlled process to a specified reference signal.
An Automatic Hybrid Method for Retinal Blood Vessel Extraction
Authors: Yang Yong , Huang Shuying , Rao Nini
Published: October 2008

An Automatic Hybrid Method for Retinal Blood Vessel Extraction

The extraction of blood vessels from retinal images is an important and challenging task in medical analysis and diagnosis. This paper presents a novel hybrid automatic approach for the extraction of retinal image vessels. The method consists in the application of mathematical morphology and a fuzzy clustering algorithm followed by a purification procedure. In mathematical morphology, the retinal image is smoothed and strengthened so that the blood vessels are enhanced and the background information is suppressed. The fuzzy clustering algorithm is then employed to the previous enhanced image for segmentation. After the fuzzy segmentation, a purification procedure is used to reduce the weak edges and noise, and the final results of the blood vessels are consequently achieved. The performance of the proposed method is compared with some existing segmentation methods and hand-labeled segmentations. The approach has been tested on a series of retinal images, and experimental results show that our technique is promising and effective.
Numerical calculations of behaviour of ship double-bottom structure during grounding
Authors: Niklas Karol
Published: October 2008

Numerical calculations of behaviour of ship double-bottom structure during grounding

The idea of the CORET project consists in adding, to the existing construction, special polymer-concrete coatings intended for the increasing of ship's capability against losing structural tightness during collision or grounding. In order to correctly design the protective barriers, to perform relevant numerical simulations is necessary. The elaborating of numerical models of ship structure behaviour during collision is very complicated and requires auxiliary simulations (on submodels) to be performed. This paper is devoted to elaborating a numerical model of a fragment of ship double-bottom structure. On the basis of experimental tests it was possible to verify and calibrate the numerical model which may be used in further design work aimed at the increasing of crashworthiness of structure during collision.
Calculation of oil outflow from fuel oil tanks of a containership with polymer coatings applied to double bottom tanks — in the light of Resolution MEPC. 141(54) of IMO
Authors: Wtadziński Grzegorz , Rutkowski Zbigniew
Published: October 2008

Calculation of oil outflow from fuel oil tanks of a containership with polymer coatings applied to double bottom tanks — in the light of Resolution MEPC. 141(54) of IMO

Introduction of the semi-elastic barrier into fuel tanks rise environmental protection level in case of ship collision or grounding. Last law regulations requires change of localisation of fuel tanks in ship structure in a such way to increasing distance between fuel and surounding water. Application of semielastic barrier into fuel tank make possible to localise fuel tanks in double bottomspace. Calculation of hipothetical outflow of fuel from damaged fuel tan in case of application of senielastic barier is presented.
Heavy metal content in soil and consumption yield in the vicinity of petrochemical plant
Authors: Karaczun Zbigniew , Indeka Leonard , Obidoska Grażyna
Published: October 2008

Heavy metal content in soil and consumption yield in the vicinity of petrochemical plant

The research on soil and consumption yield quality at the impact zone of the petrochemical plant in Płock (ZRiP), conducted in the 1970s and 80s, proved that the emissions from the plant threatened the agricultural production within the area. As the emission levels from the ZRiP have significantly dropped in recent years, analyses were conducted in order to assess the current content of Cd, Cr, Cu, Ni, Pb and Zn in soils as well as in wheat grain and potato tuber cultivated within the area. The results showed that the soils were not contaminated with above mentioned heavy metals, but the level of cadmium was exceeded in potato tubers collected from three research points and in wheat grain collected from one point.
Use of computed tomography to evaluate a fracture associated with a subchondral pedal bone cyst in a horse
Authors: Del Chicca F. , Kuemmerle J. M. , Ossent P. , Nitzl D. , Fuerst A. , Ohlerth S.
Published: October 2008

The radiological examination of bone lesions can be challenging, considering the complex superimposition of the 3D anatomy of a region on to a 2D image. This report describes the findings achievable with different diagnostic imaging modalities (radiography, arthrography, spiral computed tomography) and the correlation with thepost mortemand histopathological findings in a horse with a fracture associated with an osseous cyst‐like lesion in the third phalanx. CT was highly superior to radiography to evaluate the spatial configuration and completeness of the fracture, relationship between the fracture and osseous cyst‐like lesion, architecture of the cyst, presence of its communication with the joint and secondary degenerative joint disease. In conclusion, CT represents an asset in these cases for an accurate prognosis and therapy.
Proposed Mathematical Model for Daily and Seasonal Thermal Bridge Displacements
Authors: Arsoy Sami
Published: October 2008

A change in temperature causes a material to change length. Like most structures, bridges are subject to daily and seasonal thermal displacement cycles due to varying temperatures. In conventional bridges, expansion joints and seatings are used to accommodate these displacements. In integral bridges, the expansion joints are eliminated, and this results in rigid connections; hence, the superstructure, the bridge abutments, and the piles undergo varying displacements during each temperature cycle. To understand the temperature-induced soil–structure interactions, a realistic thermal displacement model that considers the realistic temperature variation cycles is necessary. This study discusses first the factors affecting bridge temperature variations and then a practical treatment of these effects in the design stage. The proposed mathematical model for thermal bridge displacement patterns considers the realistic changes in both daily and seasonal temperature cycles over time and the construction temperature. The usability, practicality, and importance of the model are verified by large-scale laboratory tests on segments of a bridge abutment supported by two pile types. The study shows that the proposed method is practical and capable of detecting detrimental effects induced by daily thermal displacement cycles. Potential uses of the proposed method are also discussed via a numerical example in which temperature and thermal displacement patterns measured for a real bridge are compared with estimates from the proposed model. This model was found to compare well with the measured data.
New Aesthetic Type T-1F Bridge Rail from the Texas Department of Transportation
Authors: Williams William
Published: October 2008

Aesthetic bridge railings that are Test Level 3 (TL-3) crashworthy have great appeal. As part of the project described here, the author worked closely with other designers from the Texas Department of Transportation to design, develop, and crash test an aesthetic and crashworthy bridge rail that meets NCHRP Report 350 TL-3 requirements. The aesthetic features of this bridge rail are easy to construct and repair. The bridge rail elements are mechanically attached to the posts and are not welded, to make the railing easier to construct and repair. The posts are fabricated from steel plate and are attractive and easy to construct. The rail elements, fabricated from high-strength aluminum, are attached to the steel posts after those are installed. The rail elements can be adjusted once in place and are also standardized highway barrier hardware. As a result of some simple and cost-effective curb reinforcement details developed as part of this project, damage to the concrete curb and deck was minimal from the crash testing. In addition, from previous testing, a TL-3 crashworthy transition had already been tested and approved for this new aesthetic bridge rail design. This bridge rail design is currently being implemented on new construction in Texas. This paper presents an overall review of the design of the aesthetic bridge rail, details of the design, aspects of construction, and results from the crash testing of the T-1F bridge rail.
Advancements of New Narrows Suspension Bridge Design in Tacoma, Washington
Authors: Serzan Kenneth , Spoth Thomas
Published: October 2008

The suspended superstructure of the new Tacoma Narrows Suspension Bridge in Washington State consists of twin welded steel trusses with a continuous and integral orthotropic steel deck measuring over 1 mi in length. AASHTO M270 Grade 50 HPS 50W and HPS 70W steels are the materials of choice. The truss elements are fabricated of both closed-box and open I-sections. The bridge, including major components of the stiffening truss, was designed to allow for a future lower roadway or light-rail transit system. This paper discusses the design aspects of this 5,400-ft suspended superstructure, including the development of design details to satisfy performance requirements for serviceability, fatigue, wind, and seismic loading. Global superstructure and local component computer modeling techniques are presented as they relate to force, fatigue, and displacement demands and overall structural performance for the 150-year design service life. Fabrication and lessons learned are also discussed.
Impact Echo Data from Bridge Deck Testing
Authors: Gucunski Nenad , Slabaugh Greg , Wang Zhe , Fang Tong , Maher Ali
Published: October 2008

Accurate assessment of the condition of bridges leads to their economic management. Ultrasonic seismic methods can be successfully used for this purpose through evaluation of changes in material characteristics and detection of the development of defects and zones of deterioration. The impact echo (IE) method is of special benefit in evaluation of corrosion-induced deck delamination, due to the method's nondestructive nature, speed of evaluation, and ability to detect delaminated zones at various stages of deterioration: from initial to progressed and developed. The traditional approach in condition assessment of bridge decks by IE on the basis of review of individual test point records and a new automated approach based on three-dimensional (3-D) data visualization are presented. The developed 3-D visualization platform allows both the advanced presentation and interpretation of IE data. The data presentation is provided as 3-D translucent visualizations of reflectors in a bridge deck section and horizontal and vertical cross sections through all distinctive zones, including a zone of delamination. The associated interpretation platform allows both (a) the overall assessment of the condition of the deck, through cumulative distributions and histograms of reflection intensity, and (b) identification of deteriorated zones of the deck for repair or rehabilitation in an efficient and intuitive way. The visualization platform effectively enables an IE device to be used as a type of bridge deck sonar device.
Impact Echo Data Analysis Based on Duration and Bandwidth of Signal Components
Authors: Algernon Daniel
Published: October 2008

Impact echo (IE) is successfully applied for the nondestructive evaluation of concrete structures. Its principle is based on the use of longitudinal waves generated by the elastic impact of a steel sphere. However, this impact creates other wave types such as Rayleigh and shear waves. Especially when IE is applied on structures with compact dimensions, the effects of these waves become crucial. The separation of the different signal components and the definition of effective criteria to distinguish between them are therefore highly relevant. In this study, the duration and attenuation of the different signal components are explained and used to distinguish between the actual measurement information and interfering effects caused by reflections at the boundaries. An explanation is offered for why the different components of an IE signal have different characteristics in regard to their duration over time. Furthermore, a procedure is introduced that makes use of the relation between the signal duration in the time domain and the bandwidth in the frequency domain. It therefore avoids the application of a rather complex time– frequency analysis. This characteristic is demonstrated on simple sinusoidal signals in a first step and then applied to data collected from IE measurements. Because of the low computation effort and the fact that only few input parameters have to be chosen, this method is also applicable to whole scan lines composed of a large number of measurement points and the imaging of the results.
Field Measurements and Numerical Analyses of Double-Layer Pipe Roof Reinforcement in a Shallow Multiarch Tunnel
Authors: Yang J. S. , Gou D. M. , Zhang Y. X.
Published: October 2008

The longitudinal deformations of the pipe roof in the entrance of a shallow multiarch tunnel of Tujiangchong were monitored by a series of strain gauges, and the working mechanism of the pipe roof was analyzed according to the field test results. A three-dimensional finite difference code, FLAC3D, was adopted to simulate the deformation of the pipe roof and to evaluate its effect on ground surface settlement. Both the calculated and numerical results fit the field observations quite well. The numerical results indicated that a double-layer pipe roof provided a restraining effect on ground movement and helped to reduce the tunnel deformation and corresponding ground surface settlement. Ground settlement directly above the crown could be reduced by 40% to 50% compared with the settlement induced by tunneling without any pipe roof reinforcement. This project provided a successful case history of using double-layer pipe roof reinforcement in a shallow multiarch tunnel construction.
Using Warm-Mix Asphalt Technology to Incorporate High Percentage of Reclaimed Asphalt Pavement Material in Asphalt Mixtures
Authors: Mallick Rajib B. , Kandhal Prithvi S. , Bradbury Richard L.
Published: October 2008

The use of reclaimed asphalt pavement (RAP) helps save natural resources and money. The percentage of RAP that can be utilized successfully in hot-mix recycling is primarily dictated by practical considerations. To avoid deterioration of the aged binder, RAP should not be exposed to relatively high temperatures. This study investigated the feasibility of using a warm-mix asphalt (WMA) additive, Sasobit H8, in successfully recycling hot-mix asphalt (HMA) with 75% RAP at a lower temperature. A control HMA was prepared with extracted aggregates and PG (performance grade) 64-28 binder at 150°C. Another HMA was produced with PG 52-28 binder at 135°C. Two WMA mixes were prepared with Sasobit H8 at 125°C, one with PG 52-28 and the other with PG 42-42 binder. Samples with design asphalt content were compacted by using 75 gyrations of the Superpave gyratory compactor. Their voids, tensile strength at −10°C, rutting potential at 60°C, and moduli at 0°C, 25°C, and 40°C (at different times) were determined and compared. The moduli samples were subjected to 60°C in between the tests. The results show that it is possible to produce mixes with 75% RAP with similar air voids as virgin mixes at lower than conventional temperatures using 1.5% Sasobit. The addition of a significantly lower grade of binder, PG 42-42, at a rate of 1.5% by weight of mix produced a mix that is most comparable with a virgin mix.
Effect of Reclaimed Asphalt Pavement (Proportion and Type) and Binder Grade on Asphalt Mixtures
Authors: Li Xinjun , Marasteanu Mihai O. , Williams R. Christopher , Clyne Timothy R.
Published: October 2008

Reclaimed asphalt pavement (RAP) has been used in the United States for more than 25 years because of the benefits in costs and environmental stewardship. The recent substantial increases in asphalt prices have led asphalt technologists to examine the increase in RAP use. The evaluation of the performance of the asphalt mixture containing RAP is therefore a priority for the asphalt materials community. This paper investigates the effect of RAP percentage and sources on the properties of asphalt mixtures. Ten asphalt mixtures, including two different RAP sources, three RAP content percentages (0%, 20%, 40%), and two different asphalt binders (PG 58-28 and PG 58-34) were investigated in this study. The complex dynamic modulus was performed on all mixtures at different temperatures and frequencies, and semicircular bend (SCB) fracture testing was performed for all mixtures at three low temperatures. Experimental results indicate that asphalt mixtures containing RAP have higher dynamic modulus values than the control mixtures containing no RAP. The stiffer asphalt binder was found to result in higher dynamic modulus values for both the control and the RAP-modified mixtures. Experimental data also show that the RAP source is not a significant factor for the dynamic modulus at low temperatures, although it significantly affects dynamic modulus values at high temperatures. In addition to test temperature, the RAP percentage was found to significantly affect the SCB fracture resistance of mixtures. However, for the dynamic modulus, values for the softer binder were higher than for the stiffer one at low temperatures. No significant statistical relationship between dynamic modulus and fracture energy was found.
Evaluating Airline Service Quality by Data Envelopment Analysis
Authors: Higgins Kevin M. , Lawphongpanich Siriphong , Mahoney John F. , Yin Yafeng
Published: October 2008

Data envelopment analysis (DEA) is used to evaluate the service quality of airlines. Although DEA can handle more, four quality factors available from the Air Travel Consumer Report, maintained by the U.S. Department of Transportation (USDOT), are the focus: fractions of flights that were on time, passengers with reservations who were denied boarding, passengers who reported mishandled baggage, and passengers who filed complaints with USDOT. Instead of relying on weights established by surveying the opinions of industry experts and frequent flyers, DEA uses an optimization technique to evaluate the service quality of each airline relative to others. To illustrate, data from Calendar Years 2000 to 2006 were used to compute the monthly service qualities of domestic airlines. Results from these data suggest that DEA rankings are similar to those based on the airline quality rating. The latter appeared in the media for more than a decade.
Segmentation and Positioning Analysis for International Air Travel Market
Authors: Wen Chieh-Hua , Lai Shan-Ching , Yeh Wen-Ya
Published: October 2008

Market segmentation for international air travel is explored, and how airline passenger perception positions air carriers is identified. Data for the empirical study were collected from international airline passengers who flew to Tokyo from Taipei. Factor analysis was initially performed to categorize service attributes of airlines into four underlying factors: onboard amenity, ground service, flight safety and corporate image, and travel cost and time. Cluster analysis divided the air passenger travel market into three distinct segments. For each market segment, correspondence analysis produced perceptual maps that reveal the positioning of the airlines and their attributes. Managerial implications of the empirical findings are discussed.
Development of Frost and Thaw Depth Predictors for Decision Making about Variable Load Restrictions
Authors: Baïz Sarah , Tighe Susan L. , Haas Carl T. , Mills Brian , Perchanok Max
Published: October 2008

Low-volume roads covering the northern part of Ontario, Canada, are a critical asset; they enable the movement of goods from remote resource areas to markets. However, challenged by a combination of heavy, low-frequency traffic loading and a high number of freeze-thaw cycles for which most have not been structurally designed, such highways often experience seasonal damage and premature traffic-induced deterioration. To mitigate these impacts, the Ontario Ministry of Transportation and other departments of transportation place seasonal load restrictions (SLRs) every year during the spring thaw. For economic reasons, the duration of SLRs is usually fixed in advance and is not applied according to conditions in a particular year. Rigidity in the schedule may result in economic losses because the payload can be unnecessarily restricted or pavement deterioration can occur. The latest attempts to address this issue include the use of climatic and deflection data to assess the bearing capacity of the roadway better. The use of frost and thaw depth predictors to track spring thaw weakening could improve the scheduling of load restrictions. On the basis of field data captured in Northern Ontario, a good correlation was found between the amount of frost depth in the pavement and weather conditions monitored by road weather information systems. An empirical methodology for site-specific calibration of the predictors is proposed, and the steps toward its development and the calculation algorithms are detailed.
Evaluating Climate Change Impact on Low-Volume Roads in Southern Canada
Authors: Tighe Susan L. , Smith James , Mills Brian , Andrey Jean
Published: October 2008

Information extracted from global climate models suggests that average temperatures and annual precipitation will increase over the next several decades, with potential implications for pavement performance and design. With Canadian data from the Long-Term Pavement Performance program, the Mechanistic-Empirical Pavement Design Guide was used to quantify the impacts of projected climatic changes on pavement performance of low-volume roads at six sites. A series of analyses was conducted to assess the impact of pavement structure, material characteristics, traffic loads, and changes in climate on incremental and terminal pavement deterioration and performance. Results suggest that rutting (asphalt, base, and subbase layers) and both longitudinal and alligator cracking will be exacerbated by climate change, with transverse cracking becoming less of a problem. In general, maintenance, rehabilitation, and reconstruction will be required earlier in the design life; however, the effects of climate change were found to be modest relative to effects of regional baseline climate differences and increased future traffic. For road authorities, key adaptations will relate to when and how to modify current design and maintenance practices. Pavement engineers should be encouraged to develop a protocol for considering potential climate change in the development and evaluation of future designs and maintenance programs. Incorporating other climate-related road infrastructure issues– for instance those associated with concrete pavements; surface-treated roads; and airfields bridges, and culverts–would be beneficial. At a minimum, long time series of historic climatic and road weather observations (e.g., >30 years) should be incorporated into analyses of pavement deterioration and assignment of performance graded materials.
Sensor Technology for Decision Support of Spring Load Restrictions
Authors: Yu Xinbao , Liu Nina , Yu Xiong (Bill) , Li Ning
Published: October 2008

Spring load restrictions (SLR) are commonly used as a pavement preservation strategy in cold regions. Implementation of SLR has been found to bring about significant economic benefits by extending the pavement service life. Monitoring the degree of soil freeze-thaw status is crucial for making sound decisions on SLR implementation. Current tools to assist this decision are limited; they are unreliable and unable to provide timely data. As a result, the decisions on starting and ending of SLR, as well as the magnitude of load restrictions, are highly subjective. There remains room to optimize the benefits of this important transportation policy. A sensor and analysis method based on the time domain reflectometry (TDR) principle was developed that can accurately measure the degree of soil freeze-thaw status. Interesting results were obtained by using this technology to study the effects of freeze-thaw on soil mechanical behaviors. This sensor technology can assist in the implementation of SLR by (a) helping set the duration of SLR from accurately determining the degree of soil freeze-thaw status and (b) optimizing the level of road restrictions to optimize the cost and benefit between pavement preservation and freight industry. A field implementation of this technology is being conducted at Mn/Road, the world's largest and most comprehensive outdoor roadway laboratory.