bluuebunny/crossref_metadata_2025 huggingface dataset:
Fiber-Reinforced Polymer Repair and Strengthening of Structurally Deficient Piles
Authors: Sen Rajan , Mullins Gray , Shahawy Mohsen
Published: February 2008

The poor durability of conventional repairs has led to increased interest in the application of fiber-reinforced polymers (FRP) for repairing corroded concrete structures. The availability of resins that can cure under wet conditions has made it possible to consider FRP for repairing partially submerged piles. An overview is provided of a recently completed multiyear study that investigated this problem. In the project, laboratory studies were conducted to determine the effectiveness of FRP in corrosion repair, and two field demonstration projects were completed. A simple, new design method was developed and used for the design of the FRP wrap in the demonstration projects. Some of the issues related to pile repair are addressed, with particular attention to the newly developed design method.
Field Tests to Determine Static and Dynamic Response to Traffic Loads of Fiber-Reinforced Polyester No-Name Creek Bridge
Authors: Zhou Eric , Wang Youqi , Meggers David , Plunkett Jerry
Published: February 2008

No-Name Creek Bridge, built in Russell, Kansas, in 1996, is the first all-composite highway bridge in the United States. Its structural panels are built of glass fiber-reinforced polyester sandwich panels with honeycomb cores. The bridge surface is made of polymer concrete. Two static field tests were conducted, one shortly after its completion in 1996, the other in 1997. In September 2004, after 8 years of service, field tests were repeated to examine the environmental effect on the composite materials. Test results were compared with previous results. No significant change of the bridge rigidity was found after 8 years. In addition, dynamic response to moving traffic loads was investigated. An AASHTO Type 3 truck, with a gross weight of 70,340 lb, was used to apply the traffic load to the bridge. Four types of tests were conducted: static loading, crawl speed loading, moving traffic loading, and impact traffic loading. Dynamic factors and natural frequency were measured.
Interaction between Transport, Infrastructure, and Institutional Management
Authors: Gustafsson Inger
Published: February 2008

Ongoing research on how to support high-quality information for intermodal transport is reported. The research approach suggests that the interaction between the domains of transport, infrastructure, and institutional management is a step forward. This kind of interaction must be formalized and structured through a specific infrastructure, and someone must be responsible for the development and maintenance of this infrastructure. Research results of 54 semistructured interviews conducted as a prestudy for a port community system (PCS) in the Port of Gothenburg, Sweden, are used as empirical data. Results indicate that cooperation and information sharing within the port cluster are far from a highly integrated supply-chain management solution. Results also reveal major gaps regarding the recognition of each other's situation, especially between authorities and the shipping industry. With a PCS viewed as an interaction infrastructure, the approach of the Port of Gothenburg stresses the need for interaction among the different domains as well as the need for a strong initiator and developer. For the system to become successful, it must achieve a certain status as useful and trusted by the many who must update the system in a timely manner. For trust to be built into the system, development and implementation must be done in close cooperation with the many actors. The actors must think outside of their own systems; information crucial to each individual actor's operation also can be of value to others.
Optimization of Internal Transport Cycle in a Marine Container Terminal Managed by Straddle Carriers
Authors: Soriguera Francesc , Espinet Domenec , Robusté Francesc
Published: February 2008

Combined with the success of containerization, globalization has brought about tremendous increases in container transport around the world. Increased container transport leads to larger container ships, which increase demands on seaport container terminals and their equipment. In this situation, the success of container terminals depends on a fast transshipment process combined with reduced costs. It is thus necessary to optimize the three main logistic processes at seaport container terminals: loading and unloading container ships, storing containers, and receiving and delivering containers to and from the hinterland. In another process, the internal transport subsystem ensures the interconnection between previous logistic activities. The optimization of an internal transport cycle is presented for a marine container terminal managed by straddle carriers (SCs), which are among the most used technologies for container transfer. Three subsystems are analyzed in detail: landside transportation, container storage in the yard, and quayside transportation. The conflicts and decisions that arise from operations in these subsystems are analyzed, and optimization algorithms are proposed. Moreover, a simulation is run on Spain's Barcelona Container Terminal to test the algorithms and compare different SC operation strategies (e.g., single cycle versus double cycle) and different-sized fleets of handling equipment. The simulation model is explained in detail, and the main decision-making algorithms from the model are presented and formulated.
Characteristics of Drayage Operations at the Port of Houston, Texas
Authors: Harrison Robert , Hutson Nathan , West Jason , Wilke Julie
Published: February 2008

Port drayage—defined as a truck pickup from or delivery to a seaport, with the trip origin and destination in the same urban area—is a critical, yet comparatively understudied link in the intermodal supply chain. Because port dray trucks operate primarily in urban environments, they significantly affect congestion and air quality. Drayage industry characteristics at the Port of Houston Authority (POHA) in Texas are identified to help planners prepare for continually increasing container volumes, while considering the dual needs of maintaining profitability and reducing societal costs. Results are reported from interviews with drayage managers and a survey of 103 port drivers at the Port of Houston's Barbours Cut container terminal regarding demographics, working conditions, truck characteristics, route characteristics, and port operations. The study results then are compared with existing literature, most of which originates in the area of Los Angeles, California. Substantial variation is apparent in truck age and mileage. Although few drivers were unsatisfied with overall terminal efficiency, many had suggestions for improving efficiency. Results indicate that the industry is relatively stable, despite the increasing demands that stem from high container growth rates. Finally, methods whereby the dray fleet could be modernized through grants for air quality improvement are examined.
Potential for Economic Gains from Inland Water Transport in India
Authors: Sarkar P. K. , Mathur Veni , Maitri Vinay , Kalra Kanika
Published: February 2008

Even though India has 14,500 km of navigable waterways, inland water transport (IWT) plays only a marginal role in the transport sector. Although the total cargo market in 2000 was 1,000 billion tonne kilometers, cargo movement by IWT was only about 1.5 billion tonne kilometers (i.e., a modal share of 0.15%). In India, IWT has great potential as an economical and eco-friendly mode of transport, if the necessary infrastructure investment is made in fairways, terminals, vessels, and navigational aids. A pilot study was conducted on two major national waterways, NW1 (Ganges–Bhagirathi–Hoogly River system) and NW2 (Brahamaputra River system) to determine the viability of such investments, in terms of not only financial but also potential economic gains. Certain tangible gains were quantified along with intangible social and environmental benefits. Measured as economic internal rate of return (EIRR), the project feasibility was determined to be 17%, with a positive net present value of Rs 2,290 million (1 Re = $0.025 in 2007 U.S. dollars) and a benefit–cost ratio of 1.81 at a 10% discount rate. Thus, this project also meets the World Bank norms for feasibility of public utility projects (i.e., an EIRR of 5% or more). These findings reinforce the conclusion that the government of India should undertake rapid and massive efforts for national IWT development in its 10th and 11th Five Year Plans.
Demand Elasticity and Benefit Measurement in a Waterway Simulation Model
Authors: Wang Shiaau-Lir , Schonfeld Paul
Published: February 2008

Waterway simulation models can be used to evaluate system performance and optimize investment and operation decisions, provided the effects of such decisions on demand are properly considered. Some simulation models have considered demand changes due to seasonal variations, economic growth, congestion effects on travel times, and user responses to service interruptions—but not all of these factors together. An elastic demand relationship embedded in a simulation model is used to estimate the effects of changing service times and lock closures during the simulation. Because traffic demand and benefits may be significantly affected by the simulated decisions, evaluation or optimization of the system merely on the basis of total costs is unreasonable. Estimation of the benefits to waterway users also is demonstrated during simulation runs while accounting for the users' responses to lock closures and other factors that affect travel times. Specifically, the present worth of net benefits for the entire analysis period can be computed and used as the objective function for optimization. This approach can account for infrastructure construction and maintenance costs, the effects of service quality and interruptions on user costs, and possible mode shifts in response to waterway service quality.
Environmental Effects on Deformation and Smoothness Behavior of Early-Age Jointed Plain Concrete Pavements
Authors: Ceylan Halil , Kim Sunghwan , Gopalakrishnan Kasthurirangan , Wang Kejin
Published: February 2008

In this paper, a study of environmental effects on the deformation and smoothness behavior of jointed plain concrete pavement (JPCP) during its early age is presented. A newly constructed JPCP on US-34 near Burlington, Iowa, was instrumented and monitored during the critical time immediately following construction to identify its early-age behavior regarding temperature variations. The surface profiles were measured in diurnal cycles. The primary objective of this research was to investigate the effect of the early-age curling and warping behavior on the initial smoothness of newly constructed JPCPs. Variations in temperature during these critical periods were monitored by temperature sensors installed within the pavement test sections at the time of construction. The slab deformations associated with environmental loading were quantified, and the smoothness indices (international roughness index and ride number) were computed from measured pavement surface profiles. The changes in smoothness indices at different measurement times were investigated and compared with those obtained with finite-element simulations. On the basis of variations in measured and predicted smoothness indices, it was observed that the initial pavement smoothness might be influenced by curling and warping behavior of JPCPs (during the first 7 days after paving).
MnLayer
Authors: Khazanovich Lev , Wang Qiang (Chuck)
Published: February 2008

Layered elastic theory (LET) has been used successfully for many years in the design and analysis of asphalt pavements. An attractive feature of this approach is its ability to represent the layered-pavement structure with variable interface conditions between consecutive layers. Several computer programs (BISAR, WESLEA, and JULEA) for the analysis of pavement systems were developed on the basis of LET. A new Mechanistic–Empirical Pavement Design Guide (MEPDG) procedure was recently developed by NCHRP under AASHTO sponsorship. It requires that layered elastic analysis be performed more than 1,000 times for a single design simulation of a flexible (asphalt) pavement, which makes the flexible design process extremely time consuming. An important step toward reducing the time needed to use the MEPDG software is improvement in the computational efficiency of the layered elastic analysis. In this paper, a new layered elastic analysis program, MnLayer, is presented. Several improvements in the numerical evaluation of the inverse Hankel transform of the layered elastic solutions were implemented into the program. A comprehensive comparison of MnLayer with two widely used layered elastic analysis programs demonstrated that MnLayer's accuracy matches or exceeds the accuracy of these other programs while its computational time is as little as 1/20 of theirs.
Effect of Measured Three-Dimensional Tire–Pavement Contact Stress on Pavement Response at Asphalt Surface
Authors: Luo Rong , Prozzi Jorge A.
Published: February 2008

Top-down cracking results from horizontal strains at the pavement surface that are caused by high wheel loads. When horizontal strains are calculated, the tire–pavement contact stress is assumed to be equal to the tire inflation pressure and to be distributed uniformly over a circular area. In reality, tire–pavement contact stress is distributed nonuniformly over a noncircular area. Actual contact stresses vary along the longitudinal and transverse directions. For precise assessment of the effect of actual three-dimensional (3-D) contact stress on pavement response, this study evaluates the horizontal strains at the surface of the asphalt layer produced by measured 3-D nonuniform stresses. The analysis evaluates five wheel loads, five tire inflation pressures, and 12 pavement structures. A multilayer linear elastic computer program, CIRCLY, was used to estimate horizontal strains in the longitudinal and transverse directions. CIR-CLY's ability to handle normal and shear stresses at the pavement surface makes it a preferred tool compared with finite element models, which are more data and computational demanding. Strain distributions due to uniform stress were also calculated for comparative purposes. The results show that horizontal strains at the pavement surface are compressive within the contact area and tensile at the edge of or outside the contact area. The vertical contact stress and transverse contact stress have significant effects on the longitudinal strains. The vertical stress dominates the developed transverse strains. Two models were developed to estimate the surface critical horizontal strains in the longitudinal and transverse directions. These equations could serve as a tool for determination of critical combinations of asphalt thickness, wheel load, and tire pressure that the uniform stress model would grossly misestimate.
Implications of Uncertainty in Distress Measurement for Calibration of Mechanistic–Empirical Performance Models
Authors: Schwartz Charles W.
Published: February 2008

Discrepancies between mechanistic–empirical (M-E) model predictions and observed field performance are conventionally attributed solely to errors in the predicted pavement distresses. However, significant uncertainty may be inherent in the measured pavement distresses due to spatial variability, sampling errors, and measurement error. A statistical approach is described for correcting field calibration for the influence of measurement uncertainty. This statistical formulation quantifies the hidden but systematic downward bias in the distresses predicted by the “calibrated” model because of uncertainty in the distress measurements. Perhaps more important, the formulation enables quantitative evaluation of the true predictive accuracy of distress prediction models by correcting for the confounding influence of uncertainty in distress measurement. Application of the methodology is illustrated through flexible pavement rutting and rigid pavement faulting data from the calibration of the M-E pavement distress models originally developed in NCHRP Project 1-37A.
Assessment of Urban Traffic Infractions in Kuwait
Authors: Al-Saleh Omar I. , Koushki Parviz A.
Published: February 2008

This research was undertaken to assess contemporary trends in driver infractions of traffic rules and regulations, in general, and the influence of driver use of mobile telephones (cell phones) while in motion, in particular. Findings have substantiated the general belief that infractions of traffic rules and regulations are on the rise, that many go undetected and unreported, that young drivers violate traffic rules and regulations more than their older counterparts, and that generally users of mobiles while in motion violated other traffic rules and regulations more frequently than their counterparts who did not use mobiles while driving. Comprehensive, continuous, and coordinated driver training, safety awareness, and education along with strict enforcement are essential to curb the rising trends in accidents and infractions of traffic rules and regulations.
Research on Pedestrian Behavior and Traffic Characteristics at Unsignalized Midblock Crosswalk
Authors: Shi Jiangang , Chen Yanyan , Ren Futian , Rong Jian
Published: February 2008

Pedestrians are vulnerable road users of the traffic system. In China, many pedestrians lack a knowledge of traffic rules and are not fully aware of safety problems. A high-risk area for pedestrians, the unsignalized midblock crosswalk is a conflict zone between pedestrians and through vehicles. In this paper, behaviors and traffic characteristics of pedestrians walking through the unsignalized midblock crosswalk without being disturbed by other pedestrians are analyzed. The data, including pedestrian speed, waiting delay, and clustering, are obtained by counting and measuring with a video camera. Pedestrian behaviors are analyzed with the use of comparisons between various categories and through statistics analysis. Pedestrian behaviors are interpreted further by analyzing pedestrians’ tactics when they cross the street and the valid gap in the vehicle flow, based on observations and measurements of pedestrians starting to walk across and of vehicle arrivals. Finally, the similarities and differences between this research and other research is explained by comparing pedestrian speed studies. Results of this research will not only help improve research on pedestrian characteristics at interrupted pedestrian facilities but will also help in developing traffic safety audit work and related countermeasures.
Comprehensive System of Road Safety Management
Authors: Li Ning , Chen Wenling
Published: February 2008

One person is killed every 5 minutes, and one is injured every minute on China's roads: China is the world leader in traffic deaths and injuries. Crash characteristics reveal that a mixed traffic environment, poor driver behavior, and a high percentage of nonvehicle occupant victims contribute to the poor measures. An uncoordinated institutional structure is identified as the most critical problem in China's road safety management. Current safety management in China is characterized by fine–incentive enforcement and remains weak in engineering and other measures. There remains room for transportation agencies to play a stronger role in China's road safety management. This paper argues that improving road safety in China calls for a comprehensive road safety management system (RSMS) with a coordinated institutional structure, complete and accurate safety data, comprehensive and effective safety programs, and strong and efficient safety legislation. The four key components of an RSMS are illustrated based on road safety management practices in the United States, which provide a benchmark for analyzing the current road safety management system in China.
Determinants of Changes in Mobility and Travel Patterns in Developing Countries
Authors: Srinivasan Karthik K. , Bhargavi P. V. Lakshmi , Ramadurai Gitakrishnan , Muthuram Vidhya , Srinivasan Sumeeta
Published: February 2008

This study analyzes changes in sociodemographic, activity, land use, and mobility patterns and their effects on travel dimensions in the context of a developing country. More specifically, increase in vehicle ownership (both two-wheelers and cars) and changes in mode choice over time are observed and analyzed with the use of household data from Chennai, India. Three sources of dynamics are analyzed: exogenous variable dynamics, sensitivity changes over time, and the influence of lagged and persistent effects. The key drivers of growth in travel demand include the increase in vehicle ownership, the number of workers, and the increase in female drivers. The influence of social and technological factors on vehicle ownership and mode choice such as peer pressure and mobile phone ownership are also significant. In addition, the effect of land use, accessibility, and activity has been investigated. Results show significant evidence of differences in travel decisions across different user segments (on the basis of driving knowledge and vehicle–worker ratio) and over time. The proposed disaggregate models provide a reasonably good description (goodness of fit is 47% to 64%) of the observed changes in travel patterns. The findings and results assume importance in the context of increasing congestion, declining public transportation share, and the imminent need for enhancing urban transportation system capacity in cities of developing countries.
Commute Mode Choice in a Developing Country
Authors: Srinivasan Karthik K. , Pradhan Gautam N. , Naidu G. Maheswara
Published: February 2008

This paper investigates mode choice decisions of workers in Chennai City, a metropolis in India. Mode choice in developing countries such as India may differ significantly from their developed counterparts in several respects. These differences pertain to vehicle types (two-wheelers versus four-wheelers), vehicle ownership levels and growth, wide variation in socioeconomic characteristics, perception of subjective factors, and variability in choice set, among other factors. Toward understanding these differences, this paper investigates the role of the following factors on mode choice: (a) differences between mode choice propensity for two-wheelers and four-wheelers; (b) differences in sensitivity to travel time and cost across different user groups based on captivity effects [captive (no vehicles), semicaptive (fewer vehicles than workers), and choice segments]; (c) alternative means of representing the unavailability or infeasibility of some alternatives to some users; and (d) the influence of subjective factors. To achieve these objectives, a series of disaggregate mode choice models are developed to capture the aforementioned effects, on the basis of data from 550 workers in Chennai City. Six alternatives are considered: two-wheeler, car, bus, train, nonmotorized, and other modes. The empirical results underscore significant variations in two-wheeler and car choice propensities. Furthermore, significant differences in sensitivity to travel time, cost, and vehicle availability are observed across different user segments. The cost sensitivity to various modes reduces as the commute distance increases. Results indicate that disregarding the aforementioned effects can lead to poor model fit, biased coefficients, and erroneous forecasts. These findings have important implications for the evaluation of transit ridership improvement strategies and demand forecasting in developing countries.
Land and Transportation Development in China
Authors: Yang Jiawen , Feng Changchun , Cao Guangzhong
Published: February 2008

This paper presents an economics perspective to help make city governments’ involvement in land and transportation development in urban China understandable. Chinese city government plays a monopolistic role in land supply because of the current land ownership by the state and the management power of the city government. City government behaves like a profit-maximizing organization because of the revenue assignment and service responsibility under the current public finance scheme. Conditioned on these institutional elements and responding to an incentive structure that lacks public involvement, rational city governments have pursued continuous new town development and neglected updating infrastructure in the older parts of cities. Road infrastructure has been emphasized, but transit investment has been neglected. Without changing the basic institutions such as land ownership, public involvement and land revenue spending regulations are essential to make city governments more responsive to the demand from the urban public.
Effect of Seat Belt Use on Road Accidents in Thailand
Authors: Boontob Nuttapong , Tanaboriboon Yordphol , Kanitpong Kunnawee , Suriyawongpaisal Paibul
Published: February 2008

This research was conducted to investigate the factors influencing seat belt use in Thailand. An additional aim was to analyze the effect of seat belt use in motor vehicle crashes with the use of injury data from hospitals. Significant factors influencing seat belt use were determined through field observations and a questionnaire survey. Seat belt use was observed to be higher in passenger cars than in pickups; lower seat belt use was observed for females, and drivers’ use of seat belts was considerably higher than that of front seat passengers and passengers in the rear seat position. Statistical analysis from the questionnaire survey found that the sex, age, education, income, vehicle type, seating position, seat belt installation, and average travel time and the interaction between age and seating position, education and income, and vehicle type and seating position significantly affect seat belt use. Probability of survival and severity index analysis found that unbelted car users could have a severity rate 67.5% higher than those who are belted. From the odds ratio analysis, car users who are unbelted have a higher fatality risk than those who are belted, as shown in the odds ratio 1.54. Fatality reduction analysis shows that with seat belt use, 35 of every 100 crash fatalities could be prevented. This study shows that by maximizing seat belt use, lives lost due to road crash injuries could be reduced annually.
Field Evaluation of New Pedestrian Crossing in Trinidad and Tobago
Authors: Mutabazi Madaniyo , Dindial Rondell
Published: February 2008

The walking mode is receiving more attention today because of its advantages over motorized transport modes, especially for short trips. However, pedestrians are the most vulnerable road users, more so in developing countries. Most pedestrian crashes in Trinidad are reported to involve a pedestrian crossing the roadway. Conventional zebra crossings are used to help pedestrians cross roadways safely; however, most drivers in Trinidad hardly yield to pedestrians who want to cross the road. The government has introduced a new pedestrian zebra crossing intended to increase the rate of drivers yielding to pedestrians. As part of the evaluation of the new crossing, observations of driver behavior were made at several of these crossings. The proportion of drivers stopping for pedestrians who have stepped in the crossing increased from 4% at crossings in which the flashing lights were not yet activated to 22% at crossings in which flashing lights were activated. Corresponding proportions for drivers who do not stop or slow to allow pedestrians to cross the road were 25% and 17%, respectively. Activation of flashing lights at zebra crossings in Trinidad has increased the proportion of drivers stopping for pedestrians and reduced the proportion of drivers who do not stop or slow down to allow pedestrians to cross the road.
Modeling of Vehicle Ownership
Authors: Sillaparcharn Pattarathep
Published: February 2008

This paper aims to address some important issues concerning the rapid growth in vehicle ownership and how different types of vehicles interact, especially in a country undergoing rapid economic development, such as Thailand. The forecasts of such growth are important for road building, traffic management, strategic transport decision making, travel demand forecasts, and other policy issues at the regional and national level. For those reasons, a series of vehicle ownership models that include (a) car, (b) motorcycle, (c) truck and heavy goods vehicle, and (d) bus and coach models is proposed, developed, and presented. These models are built on limited aggregate data, both time series and cross-sectional, and are disaggregated spatially by province, with non–log-linear weighted least squares regression. Basically, the inputs required are forecast gross provincial products per capita and population level. The model of vehicle ownership is applicable to the conventional four-stage transport model as an add-on before the trip generation stage. All proposed models have good statistical properties, that is, all statistically significant coefficients and high adjusted R2 value and good fits within 12% of observed values during the base years. The model of car ownership gives reasonable income elasticities regarding car ownership and a sensible saturation level when compared with other studies. The forecast for a case of increasing income shows that the car ownership level will increase together with the truck level. However, as people own more cars, motorcycle and bus ownership levels will decrease.
Chinese Edition of Transit-Oriented Development
Authors: Zhang Ming
Published: February 2008

Transit-oriented development (TOD) is a strategy to integrate transit and land use by focusing development around a transit station. Its principles are gaining increasing popularity worldwide in the global effort toward sustainable transportation. This paper attempts to answer two questions: Why do Chinese cities need TOD? How can TOD principles developed in the U.S. context be put into operation in urban China? The paper first introduces factors motivating communities in the United States to pursue TOD. Trends in China's urban expansion and travel growth are then reviewed, with a case made for TOD in the Chinese setting with the use of integrated land use–transit development. Next, the paper presents an operational TOD model derived from the experience of developing around transit in Hong Kong, Taipei, and mainland Chinese cities. The model is characterized as five D's squared, or 5D2, which includes differentiated density, dockized district, delicate design, diverse destination, and distributed dividends. It is emphasized that for sustainable transit, TOD should be applied as a composite policy combining land use, transportation, and transit finance.
Empirical Analysis of Commute Trip Chaining
Authors: Yang Min , Wang Wei , Chen Xuewu , Wan Tao , Xu Renting
Published: February 2008

Given the churning mass of congestion in most Chinese cities, a better understanding of simple and complex trip-chaining decision making is essential to transportation researchers and policy makers in China. Using the travel data collected in the city of Shangyu (a small city in east China), this paper develops an empirical framework to examine how individual–household sociodemographics, location factors, work schedule, and mode choice affect the individual choice between simple and complex commute trip chains. Besides descriptive statistics, cross tabulation and logistic regression are used in this research. Empirical results show that members of dual-worker households, office workers or employees in service trades, middle-aged or older workers, residents in the center of the old city or a new district, commuters using flexible modes, and workers with late work start or ending times are more likely to make complex commute trip chains.
Range Imaging as Emerging Optical Three-Dimension Measurement Technology
Authors: Teizer Jochen , Kahlmann Timo
Published: February 2008

In recent years, the need for accurate and fast visualization, modeling, and simulation of construction and transportation environments has increased the interest in optical three-dimensional (3-D) imaging technologies. This demand has led to development of a variety of enabling range sensing systems based on passive (light) and active (laser) range scanning approaches. The many existing and emerging range imaging technologies differ greatly, however, in their functional principles and specifications. One problem is the absence of a standard terminology that allows the advantages and disadvantages of each system to be understood easily. The intention here is to classify optical range imaging techniques and investigate the differences in working methods and characteristics. In particular, 3-D video range imaging cameras as state-of-the-art, large-field-of-view, high-resolution, and high-speed range sensing devices are put into perspective with existing 3-D measurement approaches. Additional focus is given to efforts to calibrate 3-D range imaging cameras, as their prototype development status currently limits their applicability to the field because of inaccurate measurements or other ambient limitations. Application-oriented experimental results and developments in range data processing methods are presented and demonstrate that 3-D video range cameras have reached a range accuracy level that allows them to be applied to some construction and transportation work tasks, for example, to improve safety in heavy equipment operation or to generate rapid 3-D, as-built models of entire scenes.
Quality Assurance of Mix Properties of Hot-Mix Asphalt Concrete
Authors: Turochy Rod E. , Parker Frazier
Published: February 2008

A typical component of highway construction quality assurance programs is the process by which highway construction elements are sampled and tested to ensure compliance with specifications and other project requirements. Results of contractor-performed tests of mix properties of hot-mix asphalt (HMA) concrete are increasingly used in the acceptance decision by many state departments of transportation (DOTs). Results of tests performed by contractors and state DOTs in Florida, North Carolina, and California consistently indicate that differences between contractors and state DOT test results for HMA concrete are statistically significant for most mix properties. Furthermore, these comparisons consistently indicate less variable and more favorable contractor test results, relative to specification limits, that give more favorable acceptance outcomes. Details of quality assurance processes (sampling and testing frequencies, verification procedures, and acceptance procedures) seem to have little, if any, effect on comparisons. Those findings provide information for state DOTs to consider in structuring their quality assurance programs, specifically the use of contractor-performed tests for acceptance decisions.
Effect of Performance Warranties on Cost and Quality of Asphalt Pavements
Authors: Shuler Scott , Aschenbrener Tim , DeDios Robert
Published: February 2008

Colorado began experimenting with performance warranties on asphalt pavements in 1998. The warranty specification on the first projects was developed with the help of the asphalt paving industry and consisted of a 3-year period in which the contractor was responsible for several forms of pavement distress. In exchange for this risk, the contractor was allowed to choose materials and methods for constructing the pavements. A study documented the cost–benefit relationship for these projects during the warranty period and beyond and compared the performance of these projects with comparable nonwarranty pavements. Cost comparisons include the initial hot-mix asphalt, maintenance, pavement evaluation team, weigh-in-motion station, and construction engineering. An analysis was also conducted on the competition, performance, and use of experimental features. The results of this analysis showed no significant difference in competition or performance of the warranty projects when compared with the control projects, and the difference in cost of the warranty projects when compared with the nonwarranty projects was determined to be negligible. The greatest difference in cost identified between the warranty and nonwarranty projects was for weigh-in-motion station installation and maintenance. These stations were installed to verify traffic levels during the warranty period on the first projects. This cost was approximately 3% of the overall project cost. Many lessons were learned on these projects, and recommendations were made to improve the current specification and increase the warranty periods to 5 and 10 years.
Rehabilitation after extra-articular stabilisation of cranial cruciate ligament rupture in dogs
Authors: Jerre S.
Published: February 2008

Patients at the Blue Star Foundation animal hospital in Gothenburg, Sweden, underwent a procedure with an extracapsular suture technique for cranial cruciate ligament rupture. Two groups were compared; one of the groups received rehabilitation by the owner, and the other received professional rehabilitation by a trained physiotherapists. The dogs where reexamined at four, 12 and 24 weeks postoperatively. The results were ‘good’ in both groups but a difference was not seen between the groups. This study shows that in the dogs with a body weight of between 25 and 50 kg with cranial cruciate ligament rupture, the extracapsular suture technic gives good results, provided that the dogs are actively walked on the leash postoperativly.
An in vitro comparison of a 2.7/3.5 mm hybrid plate alone and combined with crossed K-wires for canine pancarpal arthrodesis
Authors: Bailey R. , Shields A. , Bennett D. , Arnott J. L.
Published: February 2008

Several techniques have been described for canine pancarpal arthrodesis (PCA) with dorsal plating becoming the most accepted method for ease of placement despite the proposed biomechanical disadvantages. The aim of this study was to compare the biomechanical effects of the addition of crossed K-wires to a standard 2.7/3.5 mm hybrid PCA plate. A 2.7/3.5 mm hybrid PCA plate, alone and combined with crossed K-wires were tested. Six pairs of cadaver forelimbs were collected from medium-sized dogs with an average weight of 24 kg by elbow disarticulation. The limbs were potted and fixed in an Instron load cell (Instron, High Wycombe, UK) and axially loaded to failure. Load displacement data and mode of failure were recorded and stiffness, yield load and ultimate load at failure were calculated. The yield load (kN) of the plate and K-wire construct (1.278 ± 0.11) was significantly higher than for the plate construct alone (1.002 ± 0.07) (p = 0.00056). However, the differences between the two constructs in stiffness and failure loads were not significant
Histiocytic sarcoma of the stifle in a dog with cranial cruciate ligament failure and TPLO treatment
Authors: Simko E. , Harasen G.
Published: February 2008

A 10-year-old spayed female Golden Retriever was admitted with chronic lameness of the right hind limb. A tibial plateau leveling osteotomy (TPLO) had been performed on this leg approximately three years previously. A progressively growing soft tissue mass, affecting the right stifle, previously treated with TPLO was biopsied and found to be a histiocytic sarcoma. Previously proposed links between the development of neoplasia in the stifle region and the presence of chronic synovitis, osteotomy, orthopaedic implants, and specifically the Slocum TPLO plate, are briefly discussed.
Surgical treatment of shoulder instability
Authors: Duhautois B. , Pucheu B.
Published: February 2008

This study evaluates 76 cases of shoulder instability in dogs, functional outcome after treatment, and the effectiveness of medial biceps tendon transposition using a metallic staple. Clinical examinations of the shoulder were performed and radiographs were taken. Conservative treatment or surgery (biceps tendon transposition or arthrodesis) was then opted for on the basis of type of instability, associated lesions and dog (age, weight, behaviour). Long-term functional outcome was categorized as ‘excellent’, ‘good’, ‘average’ or ‘poor’. In our series, the most frequently affected breed was the Poodle (13%). Humeral head intermitent displacement was either medial (80%), lateral (19%) or cranial (1%). On clinical examination, 97% of the animals experienced pain. In anaesthetised dogs, shoulder instability was observed in 90% of the population. Muscle atrophy (33%) and associated radiographic lesions (34%) were less frequent. Ninety-five percent of the dogs were treated surgically, either by bicipital tendon transposition (81%) or by shoulder arthrodesis (19%). Results were ‘good’ to ‘excellent’ in 25% of the animals treated conservatively, and in 84.5% and 87.5%, respectively, in those treated by tendon transposition and arthrodesis. Complications did not arise from the use of a metallic staple to anchor the tendon during medial transposition. Tendon transposition or arthrodesis resulted in a good functional outcome in more than 80% of the dogs with shoulder instability. During the medial transposition, the biceps tendon was easily and effectively stabilized using a metallic staple.
Dexamethasone induces apoptosis in proliferative canine tendon cells and chondrocytes
Authors: Hossain M. A. , Park J. , Choi S. H. , Kim G.
Published: February 2008

Dexamethasone (Dexa) has been commonly used in humans and domestic animals, particularly in the treatment of tendon injuries and cartilage degeneration. However, it is often associated with tendon rupture and impaired tendon and cartilage healing. In the present study, we investigated Dexa’s in vitro effects on the growth of cell proliferation and the induction of apoptosis in canine Achilles tendon cells and chondrocytes. Cell proliferation after treatment with Dexa for two to six days was quantified by a 2,3-bis{2-methoxy- 4-nitro-5-sulfophenyl}-2H-tetrazolium-5-carboxyanilide inner salt assay (XTT). The results showed that Dexa could inhibit the proliferation of tendon cells and chondrocytes at increasing concentrations (0.1–50 μg/ml) compared with untreated cells. Cell apoptosis was induced by Dexa, as evidenced by the typical nuclear apoptosis using Hoechst 33258 staining. Dexa increased the apoptosis of canine tendon cells and chondrocytes in a time-dependent manner. In canine tendon cells and chondrocytes that were treated with 25 and 50 μg/ml concentration of Dexa, the number of condensed apoptotic nuclei was significantly increased. In addition, culturing with Dexa and the glucocorticoid receptor blocker, mifepristone, significantly arrested apoptosis of tendon cells and chondrocytes. Based on our in vitro data, we hypothesized that in vivo treatment with glucocorticoids may diminish the proliferation of tendon and cartilage cells by increasing apoptosis and suppressing the proliferation. Our findings suggest that Dexa could be used with caution in dogs with articular or tendon problems.
Meniscal injury following initial cranial cruciate ligament stabilization surgery in 26 dogs (29 stifles)
Authors: Hulse D. , Kerwin S. C. , Peycke L. E. , Case J. B.
Published: February 2008

Objective: To describe clinical signs, arthroscopic findings, and outcome in a group of dogs undergoing second look arthroscopy for the treatment of meniscal tears following original surgery to correct a CCL deficient stifle joint. Methods: The medical records of 26 dogs from the Veterinary Teaching Hospital at Texas A&M University and the Veterinary Orthopedic Center (Round Rock, Texas) that had second look arthroscopy for lameness following an original surgical procedure were reviewed. Pre-operative clinical findings, 2nd look arthroscopic findings and owner assessed outcome were documented. Results: Postliminary bucket handle tears of the medial meniscus were detected in 22 (75.9%) cases. Other postliminary meniscal injuries included frayed caudal horn tears of the medial meniscus 6 (20.7%), and longitudinal tears of the lateral meniscus 1 (3.4%). An audible or palpable click was present in 27.6% of cases. An improvement or resolution of lameness was reported in 96.5% of cases reported. In conclusion, tears of the medial meniscus are a significant cause of lameness in dogs subsequent to surgery for cranial crucial ligament ruptures. Increased lameness or acute onset of lameness after surgery for cranial crucial rupture is a consistent finding. In rare cases, a palpable or audible click will be appreciated. Arthroscopic evaluation and partial meniscectomy improve or resolve lameness in the majority of cases. Clinical significance: Sudden or increased lameness in dogs with historical CCL stabilization surgery should be evaluated and treated arthroscopically for postliminary meniscal injury if another cause for lameness can not be determined.
The biomechanical properties of the feline femur
Authors: Moens N. M. M. , Runciman R. J. , Holmberg D. L. , Monteith G. M. , Gibson T. W. G.
Published: February 2008

The purpose of this study was to determine the biomechanical properties of feline long bone by testing cadaver bone from mature cats in compression, threepoint bending, notch sensitivity and screw pull-out strength. The determination of these properties is of clinical relevance with regard to the forces resulting in long bone fractures in cats as well as the behaviour and failure mode of surgical implants utilized for fracture stabilization and repair in the cat. Cadaveric cat femurs were tested in compression, three-point bending and in three-point bending after the addition of a 2.0 mm screw hole. Cortical screws, 2.7 mm in diameter, were inserted in cadaveric cat femur samples for screw pullout testing. The mean maximum load to failure of mid diaphyseal feline femurs tested in compression was 4201 ± 1218 N. Statistical analysis of the parameter of maximum load tested in compression revealed a statistical difference between sides (p=0.02), but not location (p=0.07), or location by side (p=0.12). The maximum strength of mid diaphyseal feline femurs tested in compression was 110.6 ± 26.6 MPa. The modulus of elasticity of mid-diaphyseal cat femurs tested in compression was determined to be 5.004 ± 0.970 GPa. The mean maximum load to failure of feline femurs tested in three-point bending was 443 ± 98 N. The mean maximum load to failure of feline femurs tested in three-point bending after a 2.0 mm diameter hole was drilled in the mid-diaphyseal region of each sample through both cortices was 471 ± 52 N. The mean maximum load required for screw pull-out of 2.7 mm cortical screws placed in feline femurs tested in tension was 886 ± 221 N. This data should be suitable for investigating fracture biomechanics and the testing of orthopaedic constructs commonly used for fracture stabilization in the feline patient.
Catalytic Dehydrogenation of o‐Alkylated or o‐Alkoxylated Iodoarenes with Concomitant Hydrogenolysis
Authors: Motti Elena , Catellani Marta
Published: February 2008

Palladium‐catalyzed dehydrogenation of suitable chains bonded to an ortho position of an iodoarene has been achieved by two methods both involving oxidative addition of the iodoarene to palladium(0) and palladacycle formation under mild conditions.