bluuebunny/crossref_metadata_2025 huggingface dataset:
Does Women's Attitudinal State Body Image Improve After One Session of Posture Correction Exercises?
Authors: Scarpa Stefano , Nart Alessandra , Gobbi Erica , Carraro Attilio
Published: September 2011

Physically active people are usually more satisfied with their bodies than are sedentary people (Davis, 2002), but the influences exerted by physical activity on body image (BI) are not clear. In the current study, the effects of a posture correction exercise (PCE) session on attitudinal
state BI were examined. We wanted to know if a single PCE session could have an immediate and positive influence on attitudinal state BI in women. Participants (217 women) were randomized into 2 groups either taking part in a PCE (experimental condition) or a reading-a-newspaper (RN; control
condition) session, in a cross-over design. Before and after PCE and RN sessions, participants completed the Body Image States Scale (Cash, Fleming, Alindogan, Steadman, & Whitehead, 2002), indicating their attitudinal state BI at that time. Results showed an immediate increase in state
BI scores after a 1-hour PCE session, suggesting that the acute effect of PCE causes an improvement in attitudinal state BI.
Gender and Treatment Comparisons in a Cohort Of Patients with Psychiatric Diagnoses
Authors: Nordén Tommy , Ivarsson Bo , Malm Ulf , Norlander Torsten
Published: September 2011

Our purpose in this study was to make group comparisons of the Swedish psychiatric patient cohort called Quality Star. The present study included 1,376 patients, 753 men and 623 women, recruited from 9 outpatient clinics over the space of 6 years. All participants had serious mental
illnesses, of which patients with a schizophrenia spectrum disorder were the majority. The 4 aspects studied were consumer satisfaction, life quality, social function, and symptoms. The study had 2 main outcomes: (a) women were more satisfied with the health care and had better functioning
than men, (b) patients treated according to the Integrated Care Program had better functioning and less severe symptoms than other patients. The differences between diagnosis groups were as expected.
Teachers As Role Models for Students' Learning Styles
Authors: Shein Paichi Pat , Chiou Wen-Bin
Published: September 2011

We used modeling advantage, a concept developed by Chiou and Yang (2006), to examine the likelihood that students will identify with a particular teaching model over other competing models. In this research we examined the effects of 2 kinds of teaching styles on students' learning
styles during the collaborative teaching of technical courses. Undergraduates in a 1-semester course (229 women, 264 men; M age = 20.8 years, SD = 1.5) were given pretests and posttests to investigate how their learning styles related to their teachers' learning styles. The findings
showed that the learning styles of students were associated with their role models, which reinforced Chiou and Yang's previous work with undergraduates in different subject areas. After a semester, the learning styles of students became congruent with those of their role models. Implications
and limitations of the study are discussed.
The Big Five Personality Traits And Risky Sport Participation
Authors: Tok Serdar
Published: September 2011

The purpose in this study was to examine differences between risky sport participants and nonparticipants using the Big Five (McCrae & Costa, 1997) personality traits. The sample included 328 individuals ranging in age from 18 to 53 (M = 23.42 and SD = 3.98). The Five
Factor Personality Inventory developed by Somer, Korkmaz, and Tatar (2002) was used to measure personality traits. The results showed that risky sport participants have significantly higher levels of extraversion and openness to experience and lower levels of conscientiousness and neuroticism.
The measurement of Big Five personality traits might be a valuable means of estimating individuals' tendency to participate in adventure/risky sport, which in turn could be used to promote adventure/risky sport tourism.
The Ideal Primary School Teacher
Authors: çermik Hülya
Published: September 2011

The qualities that an ideal primary school teacher has to have according to the view of 109 teacher trainees were investigated. Data were collected from an open-ended question in which the participants' views about the ideal primary school teacher and the reasoning behind those views
were explored. Content analysis, frequency analysis, and percentage techniques of the collected data resulted in 6 themes: ethical and humanistic values; teaching skills; cultural and scientific knowledge; personal qualities; interaction with society, environment, and parents; and self-values.
Simple Stochastic Model for Planning the Inventory of Spare Components Subject to Wear-out
Authors: Brezavšček Alenka
Published: September 2011

Simple Stochastic Model for Planning the Inventory of Spare Components Subject to Wear-out

We treat an industrial system which comprises of a number of identical components subject to wear-out. To support the system maintenance an appropriate inventory of spare components is needed. In order to plan the sufficient inventory of spare components, two variants of a simple stochastic model are developed. In both variants, the aim is to determine how many spare components are needed at the beginning of a planning interval to meet demand for corrective replacements during this interval. Under the first variant the acceptable probability of spare shortage during the planning interval is chosen as a decision variable. While in the second variant the adequate spare inventory level is assessed by taking into account the expected number of component failures within the planning interval. A comparison of both variants of the model shows that calculations involved in the second variant are simpler. However, it can only be used when the inventory of spare components can be planned for a relatively long period of time.

The determination of an adequate number of spare components according to both variants of our model depends on the form of the probability density function of component failure times. Since the components are subject to wear-out, this function exhibits a peak-shaped form that can be described by different statistical density functions. Advantages and disadvantages of using the normal, lognormal, Weibull, and Gamma density function in our model are discussed. Among the probability density functions studied, the normal density function is found to be the most appropriate for calculations in our model. The applicability of both variants of the model is given through numerical examples using field data on electric locomotives of Slovenian Railways.
The Perspective of Business Process Outsourcing in Slovenian Organizations
Authors: Brcar Franc
Published: September 2011

The Perspective of Business Process Outsourcing in Slovenian Organizations

Business process management (BPM) and business process outsourcing (BPO) play an important role in organizations helping them ensure competitiveness and competitive advantages and increase efficiency and effectiveness. Our study analyzes the role of outsourcing in Slovenian organizations. Data was obtained through a survey and interpreted with descriptive statistics, frequency statistics and Wilcoxon's signed ranks test. According to the results of statistical analysis there is 95% reliability that the degree of outsourcing of business processes in Slovenian organizations will increase and this applies to most business processes. Thus we can conclude that Slovenian organizations are following the trends in global markets and are adjusting to them as well.
The effects of biological additives on the fermentation process and fibre composition of farm-scale grass silages
Authors: Lád František , Kubát Václav , Kadlec Jaromír , Čermák Bohuslav , Kobes Milan
Published: September 2011

The effects of biological additives on the fermentation process and fibre composition of farm-scale grass silages

The effects of bacterial and enzymatic additives on the course of fermentation process and on changes in the fibre composition of grass silages were investigated under farm-scale conditions over three years. Fourteen silages were prepared from die back grass stands in each of three variants, with no additive (control), with inoculants of lactic acid bacteria (LAB), and with LAB combined with cellulase and hemicellulase. The content of lactic acid was significantly (P<0.05) elevated, while the degree of proteolysis decreased (P<0.01) in both variants with the additives. The changes in the fermentation processes resulted in pH values about 4.8 and 4.3 in the control and the variants with additives, respectively. The qualitative parameters of fermentation were very similar for both the groups of additives.
Milk acetone determination by the photometrical method after microdiffusion and via FT infra-red spectroscopy
Authors: Hanuš Oto , Genčurová Václava , Zhang Yunhai , Hering Pavel , Kopecký Jaroslav , Jedelská Radoslava , Dolínková Alena , Motyčka Zdeněk
Published: September 2011

Milk acetone determination by the photometrical method after microdiffusion and via FT infra-red spectroscopy

Milk acetone (AC) and betahydroxybutyrate (BHB) are important indicators of the energy metabolism of cows (ketosis occurrence) and an effective method for their determination, with reliable results, is of great importance. The goal of this work was to investigate the infrared method MIR-FT in terms of its calibration for milk AC and to develop a usable procedure. The microdiffusion photometric (485 nm; Spekol 11) method was used with salicylaldehyde as a reference (Re) and mid infrared spectroscopy FT (MIR-FT: Lactoscope FT-IR, Delta; MilkoScan FT 6000, M-Sc) as an indirect method. The acetone addition to milk had no recovery using MIR-FT (Delta). The reference AC set must have acceptable statistics for good MIR-FT calibration (M-Sc) and they were: 10.1 ± 9.74 at a geometric mean of 7.26 mg l-1, and a variation range from 1.98 to 33.66 mg l-1. The AC correlation between Re and MIR-FT (Delta) was low at 0.32 (P>0.05 but the Log AC relationship between Re and MIR-FT (M-Sc) was markedly better at 0.80 (P<0.01). The conversion of >10 mg l-1 as an AC subclinical ketosis limit could be > -0.80 (feedback 0.158 mmol l-1 = 9.25 mg l-1) and > -1.66. This could be important for ketosis monitoring (using M-Sc).
Content of free fatty acids, lipolytic bacteria and somatic cells in relation to milking technology
Authors: Mikulová Magda
Published: September 2011

Content of free fatty acids, lipolytic bacteria and somatic cells in relation to milking technology

The contents of free fatty acids (FFA) and counts of total bacteria, psychrotrophic lipolytic bacteria (PLiBC) and somatic cells were determined in 150 samples of cow's bulk raw milk on 20 farms with three different milking technologies in South Bohemia during 2008-10. FFA were determined using an extraction-titration method. Within the compared technologies, the highest mean values of FFA (3.88 mmol 100 g-1; P<0.001) and PLiBC (696 CFU ml-1) were observed on farms with pipeline milking in stalls. The lowest mean FFA level (1.54 mmol 100 g-1) was determined on farms with an automatic milking system. Medium values were determined on farms with parlour milking.
Antibody production in sheep fed a diet containing brown seaweed
Authors: Konečný Roman , Trávníček Jan , Hasoňová Lucie , Plicka Jan , Kroupová Vlasta , Staňková Martina , Peksa Zdeněk
Published: September 2011

Antibody production in sheep fed a diet containing brown seaweed

The study is aimed to determine the effects of brown seaweed supplement in diet on immunoglobulin (IgG) and specific tetanus toxoid (TT) antibody production in gimmers. The experiment took 280 days. The experimental group E (n=6) was given 71 mg of brown seaweed in its daily diet for the whole period of the experiment, whereas the control group had no supplements in its diet. On the 245th day of the experiment the animals were vaccinated with TT to find out if the levels of antibody production would vary. The revaccination of TT was done 15 days after that. Blood samples were collected 7, 14, 21, 30 and 35 days after the first vaccination. During the study no significant differences of IgG were recorded in the blood serum between group E and C. The results suggest, in agreement with findings of other authors, that the specific TT antibody production decreases by 16% to normal during brown seaweed feeding and should be taken in consideration during targeted immunization.
Morphological and histometric parameters of the thyroid gland in slaughter cattle
Authors: Peksa Zdeněk , Trávníček Jan , Dušová Hana , Konečný Roman , Hasoňová Lucie
Published: September 2011

Morphological and histometric parameters of the thyroid gland in slaughter cattle

The study presents an evaluation of morphological and histometric parameters of the thyroid gland of slaughtered cattle (29 cows, 10 bulls, 7 heifers and 4 calves). The thyroid gland of bulls contained 34.7% of large follicles while their content in cows and heifers was 32.6% and only 19.2%, respectively. The average follicle length was 162.0±19.8 μm in bulls, 153.5±24.8 μm in cows and 122.4±10.1 μm in heifers. The highest thyreocytes were found in heifers and bulls (9.45±1.17 and 9.42±1.50 μm, respectively) and the lowest in cows (8.46±2.13 μm). A positive relationship was determined between the iodine content of the thyroid gland and the percentage of large follicles (r = 0.55) while the relationship between iodine content and thyreocyte height was negative (r = -0.21). In the thyroid gland of older cows medium and large follicles with low cubic to flat thyreocytes were dominant. Some follicles contained necrotic thyreocytes and the cytoplasm contained lipofuscin. The results suggest the influence of an increased iodine content in the thyroid gland on follicle size and thyreocyte height.
Document Clustering - Concepts, Metrics and Algorithms
Authors: Tarczynski Tomasz
Published: September 2011

Document Clustering - Concepts, Metrics and Algorithms

Document clustering, which is also refered to astext clustering, is a technique of unsupervised document organisation. Text clustering is used to group documents into subsets that consist of texts that are similar to each orher. These subsets are called clusters. Document clustering algorithms are widely used in web searching engines to produce results relevant to a query. An example of practical use of those techniques are Yahoo! hierarchies of documents [1]. Another application of document clustering is browsing which is defined as searching session without well specific goal. The browsing techniques heavily relies on document clustering. In this article we examine the most important concepts related to document clustering. Besides the algorithms we present comprehensive discussion about representation of documents, calculation of similarity between documents and evaluation of clusters quality.
Challenges for Non-Cooperative Target Identification in a Bistatic Radar Configuration
Authors: Haumtratz Theresa , Lindenmeier Stefan , Schiller Joachim
Published: September 2011

Challenges for Non-Cooperative Target Identification in a Bistatic Radar Configuration

NCTI ("Non-Cooperative Target Identification") in a monostatic radar configuration has been investigated extensively within the past years but classification in a bi-/ multistatic configuration does not seem to have obtained much attention to date. Some differences between monostatic and bistatic radar pose challenges to NCTI, which have to be met especially if monostatic and bistatic data or data with differing bistatic angles are to be compared. In this paper these challenges will be discussed and some classification procedures will be introduced. By means of data from turntable measurements of three distinct ground vehicles, which have been conducted at Fraunhofer FHR, the influence of different radar constellations on classification performance will be described.
Intelligibility Threshold for Cued Speech in H.264 Video Conference
Authors: Heribanová Petra , Polec Jaroslav , Poctavek Ján , Mordelová Angela
Published: September 2011

Intelligibility Threshold for Cued Speech in H.264 Video Conference

This paper discusses the cued speech recognition methods in videoconference. Cued speech is a specific gesture language that is used for communication between deaf people. We define the criteria for sentence intelligibility according to answers of testing subjects (deaf people). In our tests we use 30 sample videos coded by H.264 codec with various bit-rates and various speed of cued speech. Additionally, we define the criteria for consonant sign recognizability in single-handed finger alphabet (dactyl) analogically to acoustics. We use another 12 sample videos coded by H.264 codec with various bit-rates in four different video formats. To interpret the results we apply the standard scale for subjective video quality evaluation and the percentual evaluation of intelligibility as in acoustics. From the results we construct the minimum coded bit-rate recommendations for every spatial resolution.
Estimation of Heart Rate Variability Fluctuations by Wavelet Transform
Authors: Popov Anton , Karplyuk Yevgeniy , Fesechko Volodymyr
Published: September 2011

Estimation of Heart Rate Variability Fluctuations by Wavelet Transform

Technique for separate estimation of fast and slow fluctuations in the heart rate signal is developed. The orthogonal dyadic wavelet transform is used to separate the slow heart rate changes in approximation part of decomposition and fast changes in detail parts. Experimental results using the recordings from persons practicing Chi meditation demonstrated the applicability of estimation heart rate fluctuations with the proposed approach.
Enterprisewide Information Management System for Transportation Right-of-Way Activities
Authors: Sambana Kavya , Hancock Kathleen L.
Published: September 2011

Given the current state of technology–with service-oriented architecture, decentralized information, and desktop access to cloud computing and data management–enterprise systems for managing the information associated with business operations are necessary for improving efficiency and quality while optimizing resources. In transportation agencies, this situation is particularly true in the data-intense real estate offices that purchase and manage right-of-way property before construction. A structure is presented for a logical model of an enterprisewide information management system for transportation right-of-way activities. The business processes are based on the federal requirements as mandated by law and outlined in the Project Development Guide of FHWA's Office of Real Estate Services for appraisal, acquisition, relocation, and property management. The logical model is developed with the use of unified modeling language, which is considered to be a standard computer system modeling language rich in well-defined graphical notations for representing complex systems and provides the structure for developing an operational information management software program.
Analytic Hierarchy Process and Geographic Information Systems to Identify Optimal Transit Alignments
Authors: Brunner I Made , Kim Karl , Yamashita Eric
Published: September 2011

Honolulu, Hawaii, like other urbanized centers, is struggling to solve problems of transportation supply and demand. One proposed solution is construction of a fixed-rail transit system along the east-west corridor, to connect the western part of the county to the downtown work zones. Setting up a transit alignment that meets technical, social, economical, and environmental considerations is a challenge. This study coupled the technologies of analytic hierarchy process (AHP) and geographic information systems (GIS) to assist in the decision-making process of determining optimal transit alignment between the competing Salt Lake and Airport alignments in Honolulu. The goal of the AHP structure was to determine the location for the transit alignment: technical, social, economical, and environmental considerations are the criteria, and suitability levels are the alternatives. A uniform grid structure was developed: thematic maps related to the independent variables were converted into a 0.1-square-mile grid map. The grid data and survey results were entered into the AHP structure to produce an index of suitability that could be plotted in the GIS environment to indicate optimal alignments for the rail transit system on the basis of public preferences and technical criteria.
Multidimensional Data Mining of Traffic Anomalies on Large-Scale Road Networks
Authors: Gonzalez Hector , Han Jiawei , Ouyang Yanfeng , Seith Sebastian
Published: September 2011

The identification and characterization of traffic anomalies on massive road networks is a vital component of traffic monitoring and control. Anomaly identification can be used to reduce congestion, increase safety, and provide transportation engineers with better information for traffic forecasting and road network design. However, because of the size, complexity, and dynamics of transportation networks, automating such a process is challenging. A multidimensional mining framework is proposed; it can be used to identify a concise set of anomalies from massive traffic monitoring data and then overlay, contrast, and explore such anomalies in multidimensional space. The framework is based on the development of two novel methods: (1) efficient anomaly mining stemming from the discovery of the atypical fragment (a compact representation of a set of abnormal traffic patterns happening across a sequence of connected road segments, possibly spanning multiple roads, and occurring at overlapping time intervals) and (2) a multidimensional anomaly overlay model that enables the clustering of multiple atypical fragments according to different criteria (e.g., severity, topology, or spatiotemporal characteristics). The atypical fragment provides a concise, global view of the traffic anomaly situation, whereas the framework for anomaly overlay provides the power of online analytical processing to facilitate the discovery of patterns associated with different anomaly types and the navigation of anomalies at multilevel abstraction.
Seasonal Autoregressive Integrated Moving Average and Support Vector Machine Models
Authors: Zhang Ning , Zhang Yunlong , Lu Haiting
Published: September 2011

Predictions of short-term traffic volume support proactive transportation management and traveler information services. To address the periodicity, nonlinearity, uncertainty, and complexity of short-term traffic forecasting, seasonal autoregressive integrated moving average (SARIMA) and support vector machine (SVM) models are often used separately to forecast the time series of traffic flow. SARIMA can discover intrinsic relations (correlations) in time series data, especially fit for modeling seasonal, stochastic time series. In contrast, SVM has a strong nonlinear mapping ability for input and output, appropriate for solving complex, nonlinear problems. The few combined schemes that have been presented previously tend to be complicated. A simple and effective novel hybrid methodology that combines the SARIMA and SVM models is proposed to take advantage of the individual strengths of the two models. Two key issues in building a hybrid model process are discussed: identification of SVM input dimensions via SARIMA and parameter optimization of the hybrid model with particle swarm optimization. Experimental results with real-world data sets indicated that the hybrid model was superior to the individual SARIMA or SVM model in terms of root mean square error and mean absolute percentage error for the prediction of the short-term traffic flow.
Comparison of Earthwork Computation Methods
Authors: Hintz Cassie , Vonderohe Alan P.
Published: September 2011

Modern technologies for data collection, data processing, and highway design allow for accurate representation of terrain-specific information to support volume computations for earthwork. These technologies support the representation of existing ground, design, and final as-built surfaces that can be overlaid and differenced to obtain volumes. However, most state highway agencies still use, or even specify, the average-end-area method, which relies on a coarse abstraction of cross sections. Results of an investigation of three highway design and construction data sets indicated, as expected, that when the cross-section interval was decreased, average-end-area volumes approached those computed by the surface-to-surface method. There could be exceptions, explainable by coincidence of the arbitrary cross-section interval and random variability of the terrain. Study results indicated that differences between the two methods could approach 5% when the cross-section interval was 100 ft. On one of the tested data sets, this difference in construction costs represented $112,500 for fill and $95,800 for cut.
Application of IntelliDrive Information System to Enhance High-Speed Intersection Safety
Authors: Yi Ping
Published: September 2011

Traffic safety at high-speed intersections remains a critical problem in traffic operations and control. Although advance detectors are used to respond to varying traffic demands, most detectors (loops or video) in use today are placed at fixed points at intersection approaches according to the roadway design speed. Because the location and size of a dilemma zone vary with changes in traffic and roadway conditions (e.g., excessive speeds or reduced roadway friction on wet or icy pavement), the permanent placement of detectors offers limited protection for approaching vehicles. The vehicle-tracking capability of the IntelliDrive system is investigated as a solution to provide vehicle data at high-speed intersections. By obtaining constant speed information of the approaching vehicle, the system determines and provides the most needed protection zone for the vehicle to reduce traffic conflicts. When properly designed, the intersection operates more safely and, in some cases, more efficiently because unneeded time extensions can be eliminated. The effectiveness of the proposed vehicle protection concept is demonstrated in a case study, in which the probability of max-out and the reliability of dilemma zone protection are analyzed and compared with those of a fixed detector scheme.
Managing Trams and Traffic at Intersections with Hook Turns
Authors: Currie Graham , Reynolds James
Published: September 2011

Signalized intersections with trams in mixed traffic are problematic because of conflicts with traffic making opposing turns and the delays that they cause for trams. In Melbourne, Australia, an approach called a hook turn, used for more than 50 years, removes this barrier because turning traffic must wait in curbside lanes to make turns when signals for the side road turn green. This paper presents a review of the hook turn and explores operations and safety impacts. Hook-turn styles of maneuvers are in use for buses in Australia, traffic in China and the United States (Illinois), and bikes and motorcycles in several countries. In each case, hook turns relocate opposing turns to improve intersection safety and efficiency. Operational analysis of the traffic impacts of hook turns in Melbourne suggest that they act to reduce congestion because turning traffic does not delay through vehicles. In addition, 38% of drivers tend to avoid hook turns; that decision acts to increase intersection capacity. An analysis of tram delay suggests a savings of 11.25 s to 15.64 s per tram and of three to five trams being added to the fleet compared with the number needed in an operation without hook turns, or between Aust$15 million (US$12.9 million, in 2010 dollars) and Aust$25 million (US$21.5 million) in fleet capital costs. A series of safety analyses with crash data and conflict point analysis demonstrates that intersections with hook turns have better safety performance than conventional intersections. Hook turns act to improve intersection operations and safety with trams in the Melbourne context. However, challenges with driver understanding and compliance are major barriers to adoption of hook turns in other areas.
Analysis and Mitigation of Safety Issues at Curbside Tram Stops
Authors: Currie Graham , Tivendale Knowles , Scott Richard
Published: September 2011

This research examines safety issues at curbside tram stops in Melbourne, Australia. Tram passengers wait on the curb and access trams arriving in the middle of the road by walking across unprotected traffic lanes. Auto traffic rules say stop when trams do but are the only protections for tram passengers crossing at curbside stops. Melbourne has 1,785 curbside tram stops (61% of all stops), including local, arterial, interchange, and terminus stops, with various risk exposures. Previous research identifies the curbside tram stop as being more dangerous than other stop designs. Accident data show that from 1999 to 2009 between 38 and 53 pedestrian accidents occurred near tram stops each year (no trend). Ridership growth means that accident rates per rider have fallen 50% in 10 years. Most accidents are not serious; however, one fatality occurs triennially (all involve individuals aged 55 years or older). A high share of accidents involves children and teenagers, and 65% occur at curbside stops, with most occurring at terminus and transfer stops. Mitigation measures are developed and evaluated. Overall investment in platform stops, greater separation of passengers at stops, and the use of formal pedestrian crossings are recommended. Barriers and increases in the widths of safety zones are recommended, as is narrowing roads to reduce driver speeds, including the use of general traffic restriction measures and the use of warning signs on trams. Closing curbside stops is also highlighted as a useful measure on all criteria. Overall research demonstrates that curbside stops have inherent safety concerns but that mitigation measures are available at various levels of cost and effectiveness. More research about stop safety in streetcar contexts is needed, and areas for this are suggested.
Rail Transit Safety
Authors: Nelson David O. , Streit Adamson E.
Published: September 2011

In December 2009, the U.S. Department of Transportation proposed to establish and enforce minimum federal safety standards for rail transit systems to correct the status quo with 27 state programs responsible for rail safety and the resulting inconsistency in practices and effectiveness. In the study described in this paper, a statistical analysis of publicly available safety data was conducted to address two questions empirically: (a) How safe is rail transit compared with other modes of transport? (b) Does a statistically significant record of inconsistent safety exist among rail transit agencies? The analysis found that travel by rail transit was generally safer than travel by automobile or truck, but statistically significant long-term differences in safety records existed in the array of domestic heavy rail and light rail operations. However, a detailed review of the findings showed the difficulty in assigning these differences because of inconsistent regulation and enforcement, as some of the most profound differences were found in agencies that operate in the same state under the same regulatory regime. Finally, the analysis found that incident and injury rates were statistically poor predictors of fatality rates. This finding suggested that rail transit fatalities were so infrequent that existing information concerning rates of incidents and injuries had little or no statistical value in predicting the incidence of fatal accidents. Further statistical analysis of fatality rates might be fruitful.
Valuing Rail Transit
Authors: Guerra Erick
Published: September 2011

A certain acrimony pervades the long-standing debate over the costs and benefits of public rail transportation in the United States. Some people seem opposed to all rail transit all the time, whereas others support any and every rail project, despite sometimes high costs and low ridership. With much debate focused on pricing automobile externalities, transportation choice, and rail's external benefits, surprisingly few studies assess which rail transit systems create net positive social welfare. If consumer benefits alone do not justify the high cost of a transit investment, what would the external value of a passenger trip have to be to do so? Combining fare, ridership, operating, and capital cost data for 24 transit agencies’ heavy or light rail systems or both, this paper makes back-of-the-envelope estimates of how transit systems’ rider benefits compare with operating deficits. Urban rail systems may not be optimal from a transportation system or economic cost–benefit perspective, but they clearly create value for consumers and society. Given a low, but commonly applied, elasticity of −0.3 and a linear demand curve, two transit systems create net social welfare gains solely on the basis of consumer surplus. At least 10 others likely provide net benefits when economic externalities are accounted for. At an elasticity of −0.6, no system provides net social welfare gains if externalities are not accounted for. At least five systems are unlikely to provide net economic benefits, even given generous assumptions about external and rider benefits.
Electric Power Supply for Commuter Rail
Authors: Allen John G. , Aurelius John P. , Black Joseph
Published: September 2011

Electrification offers many advantages for commuter railroads. But to derive electrification's full benefits, the traction power supply must meet demand. Several factors should cause commuter rail properties to assess their traction power investment needs: aging generation, transmission, and distribution systems; new cars with improved amenities and higher acceleration rates; and the addition of train starts. The traction power on all North America's electric commuter railroads and on certain overseas properties where shortfalls have occurred is reviewed. Preventive action may be appropriate on some North American properties to guarantee steady supplies of traction power. Strategies for managing power demand are discussed. Traction power is vitally important for electrified commuter railroads, because any failure to provide all necessary electricity can have serious consequences for speed and reliability.
Driving to Suburban Rail Stations
Authors: Vijayakumar Nithya , El-Geneidy Ahmed M. , Patterson Zachary
Published: September 2011

Current research focuses on pedestrian access to transit; however, commuter trains in outlying urban regions serve populations in low-density areas where many people drive rather than walk to transit services. The determinants that influence how far people are willing to drive to train stations and the factors that determine boardings at suburban train stations have not been formally studied. This paper models suburban commuter travel demand by use of the 2003 Montreal, Quebec, Canada, origin–destination survey and onboard survey data from the Agence Métropolitaine de Transport to identify characteristics of individual trips and station characteristics that influence the driving distance to commuter rail and demand at stations. The models show that methods for estimating pedestrian access distance and number of boardings per transit stop can easily be transferred to estimating driving access distance and the number of boardings per station in the park-and-ride context. The model for passenger boardings by station can be used for estimating either demand for a planned station or the effect of service interventions (e.g., parking spots) on boardings at existing stations. The paper also shows that these approaches can be a valuable tool to transit planners interested in increasing passenger demand on commuter rail through a better understanding of service characteristics.
Identification and Tracking of Highway Bridge Maintenance
Authors: Hearn George , Johnson Bruce V.
Published: September 2011

An overview of practices for highway bridge maintenance of state transportation departments (DOTs) in the United States is presented. DOT practices are given in the areas of identification of maintenance needs, numbering systems for maintenance actions, performance and priority measures related to maintenance, and data systems engaged by maintenance. The overview finds that DOTs have similar work procedures for identification and tracking of maintenance needs and somewhat similar approaches to performance and priority measures, but dissimilar practices in numbering systems for maintenance actions. Most DOTs use one or more individualized data systems to track maintenance work, monitor network-level performance, and evaluate maintenance work plans. The information presented is one product of studies of bridge maintenance decision making and bridge database development.
Bridge Maintenance in New York City
Authors: Yanev Bojidar , Richards George
Published: September 2011

The Bridge Division of the New York City Department of Transportation was established in 1988. The Bridge Division oversees the expenditure of billions of dollars from public funding sources (federal, state, and local) for the rehabilitation of the nearly 800 city bridges, including the landmark East River crossings (Brooklyn, Williamsburg, Manhattan, and Queens-borough), and a number of critically important movable bridges (Third Avenue, Willis Avenue, and 145th Street). At the time the Bridge Division was established, a concentrated effort was made to determine the needs of the bridge network for systematic preventive maintenance. Optimizing the expenditures allocated to these two fundamental bridge engineering activities has shown them to be complementary and competitive as primary methods in management of transportation networks. This paper reviews the progress of bridge management thinking and practices as they followed the similarly complementary and competitive top-down and ground-up paths, at the network and project levels, respectively, up to the present.
Estimating the Timing of Rehabilitation and Replacement of Bridge Elements
Authors: Sobanjo John
Published: September 2011

The core component of infrastructure management systems is life-cycle costing, typically used to justify the appropriate actions to the infrastructure at the best times during service life. This paper presents the results of a study on the timing of such actions, with emphasis on state-maintained highway bridges in Florida. Using historical cost data of maintenance, repair, rehabilitation, and replacement of bridge elements, the authors present and discuss basic statistical summaries of the age of bridges when the actions were applied. From the concept of age replacement models, an estimate was computed for the optimal ages at which to rehabilitate or replace some bridge elements. Weibull-type distributions were obtained as the best-fitting probability distributions of the time until a failure. “Failure time” is a term borrowed from operations research, where it implies the end of service life of items or systems, but here it means when it is necessary to repair or replace a bridge element. Optimization was then performed according to reliability models developed to minimize the average long-run costs per year on rehabilitation and replacement of the bridge elements. Advantages and limitations of the results are discussed. The proposed methodology has good potential to help the bridge manager estimate service life of bridge elements, with a consideration of the repair policy. Limitations to the direct implementation of the methodology exist, but some improvement can be achieved with future research.
Condition Survey of Older West Virginia Bridge Decks Constructed with Epoxy-Coated Reinforcing Bars
Authors: Lawler John S. , Krauss Paul D. , Kurth Jonah , McDonald David
Published: September 2011

Chloride-induced corrosion of steel reinforcing bars is a major cause of deterioration in concrete bridge decks in northern climates. Corrosion-resistant epoxy-coated reinforcing (ECR) bars were introduced in the 1970s. In 1993, the West Virginia Department of Transportation (DOT) performed surveys of bridge decks treated with ECR and uncoated bars built in the mid-1970s. While deterioration was observed on uncoated bar decks, deterioration of decks built with ECR was found to be limited. The current investigation consisted of a questionnaire and review of the condition reports of the decks examined by the West Virginia DOT in 1993, followed by field condition surveys of six decks built with ECR to determine how the ECR was performing. The six bridge decks inspected were in good to excellent condition, with the exception of two spans of Bridge 2930, which were reinforced with uncoated black bars. The decks with ECR exhibited less than 0.15% corrosion-induced deterioration. Any deterioration observed on ECR decks was concentrated at cracks or construction joints. All actively corroding ECR bars had an average coating thickness less than 7 mil (0.007 in.), the current minimum specified thickness. Decks reinforced with uncoated black bars included in the 1993 study had an initial service life of 18 to 21 years, and an overlay was applied to all of these decks to address corrosion-related damage. The decks constructed with ECR are now 33 to 35 years old, and none have required rehabilitation to address corrosion-related deterioration.
Neurocognitive function before and after surgery for insular gliomas
Authors: Wu Adam S. , Witgert Mariana E. , Lang Frederick F. , Xiao Lianchun , Bekele B. Nebiyou , Meyers Christina A. , Ferson David , Wefel Jeffrey S.
Published: September 2011

Object

Insular gliomas can be resected with acceptable rates of neurological morbidity, but little is known with regard to impairment of higher-order neurocognitive functions. The frequency and functional impact of neurocognitive deficits in patients with gliomas has until recently been underappreciated. The authors therefore examined neurocognitive function in patients with insular gliomas and compared the findings in this group to those in a matched control group of patients with gliomas in nearby brain regions.

Methods

Thirty-three patients with WHO Grade II or III insular gliomas participated in neuropsychological evaluations before and after resection. To establish whether the pattern of neurocognitive performance was different from that of other patients with tumors in neighboring areas, patients with insular tumors were matched with control patients for age, educational level, preoperative Karnofsky Performance Scale score, tumor side, grade, and volume. The control group comprised patients in whom gliomas had been resected from frontal, temporal, and parietal areas near the insula. Baseline pre- and postoperative neurocognitive test results were compared between and within groups.

Results

Preoperative neurocognitive impairment was common in both insular and control groups. Patients with insular tumors had significantly worse preoperative performance on naming tests. In both groups, postoperative decline occurred in most neurocognitive domains. There were no statistically significant differences between patients in the insular and control groups with regard to rates of postoperative decline on any test. However, there were trends suggesting differential cognitive performance postoperatively, because patients with insular tumors were more likely to experience greater decline in learning and memory. Neurological morbidity was similar to prior rates reported in the literature.

Conclusions

Few statistically significant differences in cognitive function were observed between patients in the insular and control groups at either the pre- or postoperative evaluation, although there was a trend for patients with insular tumors to exhibit greater postoperative decline in learning and memory. Although technically more challenging, surgery for insular region glioma appears feasible without profound neurological or cognitive morbidity for many patients.
Aggressive course of multiple de novo cavernous malformations
Authors: Flemming Kelly D. , Bovis George K. , Meyer Fredric B.
Published: September 2011

The risk of hemorrhage from an intracerebral cavernous malformation has been estimated at 2%–4% per year. In patients with multiple cavernous malformations, typically there are 1 or 2 dominant lesions that result in symptoms. This report highlights an unusual case of recurrent hemorrhage from de novo cavernous malformations.

This 35-year-old man had a generalized seizure in 2007. Magnetic resonance imaging performed at the time showed multiple hemorrhagic lesions suggestive of cavernous malformations. Two years later, the patient had clinical symptoms referable to a midbrain hemorrhage. This lesion was not present on 2007 standard and gradient echo images. One year later, the patient had another clinical hemorrhage at the cervical medullary junction. This lesion was also not present on earlier imaging. Genetic testing was negative for the known familial types of cavernous malformation. A lesion was biopsied to ensure correct diagnosis, and the results were pathologically consistent with a cavernous malformation. The patient had a fourth clinical hemorrhage in 2011 from a separate lesion. All hemorrhage symptoms were mild, and he returned to normal functioning and work after each hemorrhage.

This case highlights several unusual features of the known natural history of intracerebral cavernous malformations. In this case, resection of the hemorrhagic lesion would not have altered future hemorrhage risk since each new hemorrhage was from a de novo lesion.
Study of a large-scale dry slab avalanche and the extent of damage to a cedar forest in the Makunosawa valley, Myoko, Japan
Authors: Takeuchi Yukari , Torita Hiroyuki , Nishimura Koichi , Hirashima Hiroyuki
Published: September 2011

Abstarct

Accurate measurements of snow avalanche flows in forests are rare. To understand how forests can stop avalanches, we study a mixed flowing avalanche that stopped in a cedar (Cryptomeria japonica) forest in Japan. The large-scale dry slab avalanche occurred in the Makunosawa valley in Myoko on 17 February 2008 and damaged many trees. The site contains a geophone and other devices to detect avalanche activity. A nearby meteorological station provides weather information. Post-event observations were made of the scale of the avalanche and tree damage. These showed that the avalanche released from the east-southeast-facing slope at 1700 ma.s.l. Snow debris reached ~770ma.s.l; the horizontal runout distance was ~3000 m. The area of the runout zone was ~10 ha, and the snow water equivalent of debris was 400–1500 mm. The mass of the avalanche was roughly estimated at 5–10×107 kg (1–2×105m3). We used snowpack simulation models to estimate the height of the fracture zone. The simulations revealed that a faceted snow layer formed at 2 m and the stability index was 0.5 (poor) at the time of the avalanche release, due to heavy snowfall. We estimated the avalanche velocity from the bending stress of the broken cedar trees, in order to verify the effect of forests in reducing avalanche velocity. The avalanche was estimated to flow into the forest at a velocity of >26–31ms–1, with a 17 m high powder snow layer and a dense-flow layer <2m in height. It appears to have slowed down and stopped at ~130m after penetrating the upper edge of the forest.