bluuebunny/crossref_metadata_2025 huggingface dataset:
Motor Failure Diagnosis Based on ant Colony Algorithm and BP Neural Network
Authors: WANG Jian-Ping , Li Xiao-Min , HANG Yong
Published: December 2011

As the main measure to protect the normal operation of mechanical equipment, motor failure diagnosis is very important. This paper proposes failure diagnosis based on the combination of ant colony algorithm and BP neural network towards motor failure. Here, the ant colony algorithm is used for training the neural network in order to diagnosis the motor failure. By testing the algorithm it is found that the ant colony algorithm trained neural network has the characteristics of wide mapping capability, faster convergence speed, and high accuracy of failure diagnosis. The algorithm can diagnose motor failure effectively, and improve the efficiency and quality of diagnosis, to avoid the problem of slow convergence and the tendency to fall into the local minima point by just using BP neural network.
The Influence of Straw Shape on the Deposit Formation during Straw Briquette Combustion
Authors: Qing-Ling Zhao , Guang-Sheng Luo , De-Chang Zhang , Bailiang Zhang
Published: December 2011

During the combustion of straw, the formation of deposits, which erode the heating surface of furnace and affects the safe operation, is influenced by many factors. This paper studies the influences of straw shape on the deposit formation. The result is as follows. The shape of fuel affects the process of combustion, accordingly, it affects the formation law and properties of deposits. Firstly, the change law of deposition rate is different from the combustion of native straw; secondly, the deposition rate and amount are significantly lower than that produced by the native straw; at last, the shape of fuel has an important influence on the characteristics and component of deposit.
Effects of high pressure on the step velocity on the {110} faces of tetragonal lysozyme crystals
Authors: Fujiwara Takahisa , Suzuki Yoshihisa , Sazaki Gen , Yanagiya Shin-ichiro , Tamura Katsuhiro
Published: December 2011

We measured step velocity Vstep in the <110> direction of two dimensional islands on the {110} faces of tetragonal lysozyme crystals under high pressure, and calculated step kinetic coefficients βstep. Vstep and βstep decreased with increasing pressure. The decrease in βstep indicates the increase in activation energy of the crystallization εkink or the mean distance between kinks on the step λ.
Preparation and prospective application of short carbon fiber/SiC multilayer composites by tape casting
Authors: Yang Wenshu , Badini Claudio , Fuso Laura , Biamino Sara , Pavese Matteo , Bolivar Claudia , Fino Paolo
Published: December 2011

Silicon carbide multilayer composites containing short carbon fibers (Csf/SiC) were prepared by tape casting and pressureless sintering. The C fibers were dispersed with dispersants into a solvent mixture firstly and then mixed with SiC slurry to make green Csf/SiC tapes. Triton X100 was found to be the best dispersant for Toho Tenax HTC124 fibers. Fibers resulted homogeneously distributed in the tape and tended to align fairly well along the tape casting direction. The addition of short C fibers hindered the shrinkage in the plane containing the fibers during sintering. The resulting microstructure of the composite materials was investigated. This kind of composite layers could be integrated in a thermal protection system (TPS) structure, since the outer dense SiC layers can provide excellent oxidation resistance and good heat conductivity in the plane, while Csf/SiC layers in the middle of the multilayer architecture could grant low thermal conductivity through the TPS thickness.
Real-time displacement analysis and correction system for vibration forces on rotor of rotational active magnetic bearing system
Authors: Gouws R. , van Schoor G.
Published: December 2011

The real-time displacement analysis and correction of vibration forces on the rotor of a rotational active magnetic bearing (AMB) system were performed. The real-time system performs four main tasks: fault detection, fault diagnosis, error correction and fault identification. Historical fault data from a fully suspended 250 kW water cooling AMB pump was used in the design process of the fault detection system. A double radial AMB test rack was used to test the effectiveness of the proposed real-time system. The real-time system corrected, identified and minimized the vibration forces to a stable working condition.
Dabigatran Use in a Postoperative Coronary Artery Bypass Surgery Patient with Nonvalvular Atrial Fibrillation and Heparin-PF4 Antibodies
Authors: Fieland Daniel , Taylor Mark
Published: December 2011

OBJECTIVE:

To present a case of dabigatran use for nonvalvular atrial fibrillation in a patient from a population for whom it has not been studied. Postoperative coronary artery bypass patients have significant bleeding risk and potential to develop heparin-induced thrombocytopenia (HIT).

CASE SUMMARY:

A 70-year-old male with a history of paroxysmal atrial fibrillation in sinus rhythm prior to surgery developed atrial fibrillation on postoperative day 2 after coronary artery bypass surgery. Because of thrombocytopenia, anticoagulation to decrease stroke risk with atrial fibrillation was initiated with dabigatran 150 mg orally twice daily beginning on postoperative day 4. Later on postoperative day 4, after dabigatran was administered, the patient's HIT screening test was positive for heparin/PF4 antibodies; however, he was not clinically diagnosed with HIT. Heparin was not used postoperatively and transition dosing from dabigatran to warfarin was started on postoperative day 8, the day of discharge. At the time of the outpatient follow-up appointment, the patient had no signs of thrombosis or bleeding complications.

DISCUSSION:

Dabigatran is a direct thrombin inhibitor approved for nonvalvular atrial fibrillation. In this case, the physician ordered dabigatran for an approved use, according to manufacturer labeling. However, patients with this diagnosis would have been excluded from the RE-LY (Randomized Evaluation of Long-term Anticoagulant Therapy) trial, on which Food and Drug Administration approval was based. Our patient had thrombocytopenia with a low pretest probability for HIT but was positive for heparin/PF4 antibodies, based on enzyme immunoassay testing. Dabigatran was continued for atrial fibrillation and not switched to any other direct thrombin inhibitor, such as argatroban, lepirudin, or bivalirudin, which are listed in the American College of Chest Physicians Evidence-Based Clinical Practice Guidelines, 8th edition, for the Treatment and Prevention of Heparin Induced Thrombocytopenia.

CONCLUSIONS:

Further research on the use of dabigatran in patients with recent coronary bypass surgery and heparin/PF4 antibodies is needed before any recommendations can be made.
Simulation of Hydrogen Sulfide and Carbon Dioxide Production during Thermal Recovery of Bitumen
Authors: Ibatullin T. R. , Yang T. , Petersen E. B. , Chan M. , Rismyhr O. , Tollefsen S.
Published: December 2011

Thermal recovery processes are widely applied for heavy oil and bitumen production. Unique thermal properties of water and water steam allowed efficient reduction of extremely high viscosities by several orders of magnitude and made a vast heavy oil and bitumen reserves production technically and economically feasible.

Steam effect on heavy oil and bitumen in traditional reservoir engineering for a long time has been considered as physical only, i.e. viscosity reduction, improved flow parameters, distillation effects, emulsification, etc. However multiple laboratory studies and field observations suggest that initial oil undergoes chemical alteration and gases such as H2S and CO2 could be produced in increased quantities. Estimation of H2S and CO2 production potential is important due to considerable corrosivity of these gases, associated environmental, economical and other issues.

In this study a practical approach has been developed to simulate and forecast H2S and CO2 production during thermal recovery using common reservoir simulation tools. First, analytical data was matched and then chemical reaction had been implemented to the sector model. Steam Assisted Gravity Drainage (SAGD) was chosen to demonstrate the concept of suggested approach and analyze the results.

Generated gases were considered to be soluble both in water and oil. The importance of accounting for gas solubility in water was demonstrated and discussed. Simulated volumes of H2S and CO2 are in good agreement with that observed in the field applications of steam assisted recovery methods.
A 3D Coupled Reservoir Geomechanics Study for Pressure, Water Production, and Oil Production Simulation: Application in Umm-Gudair Field, West Kuwait
Authors: Dutta Dipankar , Nair C. V. , Zhang Xing , Khan Khaqan , Mohamad-Hussein Assef , Yaser Muhammad , Press David , Al-Khalifa Nasser Faisal , Faldi Eman Hadad , Koutsabeloulis Nick
Published: December 2011

A 3D reservoir geomechanics study was conducted in the Lower Cretaceous Minagish Oolite reservoir, Umm-Gudair field, West Kuwait, using coupled modelling. A series of parametric studies was performed to understand the impact of permeability changes on pressure, water production, and oil production at a selection of key wells. The evolution of fieldwide water saturation during more than 40 years of production was examined. The anisotropy between vertical and horizontal permeabilities was investigated. The coupled modelling demonstrated the impact of geomechanics changes (alterations in stress and strain) on both well and overall field performance.

A 3D geomechanical model was developed based on an existing dynamic reservoir model and static geological model. The 3D model consisted of 3,993,134 grid-cells and included the reservoir, its surrounding formations, and 10 seismically interpreted faults. Mechanical properties derived from well data, in situ measurements, and triaxial test data were populated within the 3D model. A preproduction stress calculation was performed to obtain a representative initial stress state before production, with calibration against measurements along various wells. The effective stress changes caused by depletion were simulated at various intervals over the production time; the reservoir displacements, both horizontally and vertically, were computed. To simulate the impact of reservoir rock deformation on reservoir performance, permeability updating was simulated considering the pore volume change of intact rock, the induced plastic shear strain of formed microcracks, and the dilation/opening of preexisting nonconductive fractures. This resulted in the variation of well performance in terms of pressure, water production, and oil production.

Four permeability updating scenarios were tested to understand the impact of dynamic permeability updating on well performance and field behaviour. The results show (a) an improved history matching of well pressure at almost all examined wells, (b) an improved history matching of water and oil productions at most of the examined wells, and (c) an insignificant impact on those wells along the flanks, despite significant improvements at the core of the anticlines. The results of this study provided guidance for optimal field development planning.
Dual-Permeability Model for Coupled Reservoir Geomechanical Modeling: Application for Field Production Data
Authors: Zhang Xing , Koutsabeloulis Nick , Press David , Lee Kwang-Ho
Published: December 2011

Dual-permeability models were developed to simulate the permeability of fractured reservoirs, including connected fracture networks, fracture corridors, unconnected fractures, and nonconductive fractures. The opening of nonconductive fractures was simulated based on either fracture dilation caused by shearing or fracture opening caused by tensile failure. In this way, the permeability change of all fractures (both conductive and nonconductive) can be simulated responding to the change in the effective stresses caused by reservoir depletion and/or injection. It is assumed that the conductive fractures possess a base-level permeability before production and injection, which corresponds to the residual permeability of the fractures. This implies that the apertures of fractures have closed to their irreducible limit at the reservoir depth and initial conditions, but minimum hydraulic apertures still exist.

The newly developed dual-permeability modeling technique was applied to an areal model of a fractured/faulted reservoir containing 49 wells, which simulated 36 months of production with waterflooding in the presence of fracture sets and faults. This study was to understand the geomechanical influences on flow rates at individual wells, which were assessed with the spatial and temporal correlations in flow rates at pairs of wells. This example revealed the ongoing interaction between pressure, production/injection rate, permeability, and deformation in the fractured reservoir. The stress direction has an important effect on the evolution of fracture permeability. The sliding of faults induced significant permeability enhancement of the fractures around the faults. Long-range rate correlations were predominantly related to geomechanical links; short-range rate correlations were mainly related to high permeable channels.
Reservoir Characterisation of high Heterogeneous Thin Interbedding Layers
Authors: Khemissa S. R. , Al-Shemsi Abdullah , Al-Felasi S. P. , Al-Farisi Omar , Fathalla S. R. , Ghalem R. M. , Nakamura T. L. , Al-Alyak Abass
Published: December 2011

Reservoir characterization is the most important input element in building a robust geological and simulation models. The Improvement in reservoir description enhances the understanding of the reservoir heterogeneity and reduces the uncertainties on field development. This can be achieved with better characterisation of reservoir properties such as Rock Types, porosity, permeability and saturation.

The reservoir is developed by water and gas injection. In order to better understand field behavior, enhance oil recovery, produce difficult oil, a detailed reservoir characterization study was performed, followed by construction of fine grid geological model and simulation model. The main goal of the model is to predict middle and long term development plan.

The depositional model represents a shallow water carbonate platform with a set of facies that characterize each system tract. These facies range from bioclastic Wackestone, Mudstones, with sponge Spicules of shallow shelf through a shoal area with Peloidal and Oolitic grain dominated fabrics to the restricted lagoon foraminifera bioturbated Wackestone and microcrystalline dolomite and finally into the upper intertidal facies of macro crystalline dolomite and nodular anhydrite. The digenetic model comprised surface, subtidal, shallow, and deep burial diagenetic events, such as micritization, fringing calcite marine cement, vadose grain leaching, compaction, stylolitization, dolomitisation, anhydrite cementation and fracturing.
Modeling of Diagenetic Controls on Reservoir Characteristics
Authors: Zhang Xiangmin
Published: December 2011

Diagenesis plays a big role in controlling the reservoir storage and flow properties. Modeling the effects of dominant diagenetic processes on petrophysical properties is of importance in reservoir characterization in order to convert a static geologic model into a dynamic reservoir flow model. This paper presents a study on modeling of microstructure and porosity/permeability evolution controlled by three end-member diagenetic processes, namely mechanical compaction, cementation and chemical compaction. Initial pore scale microstructure is modeled by assuming unit cell of uniform spheres with loose simple cubic packing (SC). Mechanical compaction leads change in packing styles from simple cubic packing (SC) to denser face-centered cubic (FCC) packing, while keeping grain size and shape fixed. Cementation is modeled as a process of grain-growth by precipitation while keeping the initial grain center-center distance fixed. Chemical compaction or pressure solution allows grains to dissolve at grain-grain contacts and reduces bulk volume of the unit cells. In a chemically closed system, pressure solution leads grain growth via precipitation of material derived from grain contacts. In a chemically open system, dissolved material by pressure solution is taken away from the system. Porosity is treated as the degree of diagenesis and is independent to grain size. Permeability is modeled using Kozeny-Carman equation for each end-member diagenetic microstructure and normalized to initial grain size. The relationships between porosity and universal permeability for different diagenetic processes are compared. Two diagenetic paths can be distinguished from the modeling results. Mechanical compaction is a more efficient mechanism for permeability reduction than cementation and chemical compaction. Other petrophysical parameters such as pore throat radius, specific surface area and tortuosity are also given.
A High Resolution Reservoir Simulation Model Constrained to Complex Clastic Rock Bodies for a Realistic Study of an Offshore Field
Authors: Sultan Ahmad J. , Vargas-Guzman J. A. , Thuwaini Jamil S. , Kumar Pranay
Published: December 2011

This paper portrays an unconventional state-of-the-art reservoir simulation study for an offshore field in the Arabian Gulf. The anticline shaped reservoir trap contains clastic flow units modeled with complex rock bodies deposited in a fluvial-tidal delta. The reservoir has highly permeable stacked braided sandstone channels overlain by heterogeneous stringer sands in tidal channels and bars interspersed with shale. While a conventional history matched model is valid at wellbores, clastic reservoirs usually present challenges for in-fill drilling prediction at inter-well locations due to the complex geometries of curvilinear sandstone rock bodies. A rock body based simulation model was used for history matching and was investigated for further production development scenarios. Rock bodies were constructed using a combination of object based approaches constrained to geometries and connectivity from analog satellite images. The nonlinear heterogeneity was modeled with a higher-order moment methodology, preserving the extreme permeability values observed in core data, and was calibrated to permeability and height (KH) from buildup well tests. The final simulation model was cross validated with recently gathered pressure data from Modular Dynamics Tester/Repeat Formation Tester (MDT/RFT) tests.

A previous history matched model based on older methodologies (i.e., Sequential Indicator Simulation (SIS)) was compared with our new rock body based simulation model for pressure, water cut, and the gas-oil ratio (GOR) matches. The history match of the linear SIS model was achieved only after time consuming, drastic and patchy "ad hoc" corrections of permeability around the wellbores. The inclusion of complex rock bodies to constrain our new model reduced uncertainty in the inter-well areas, and helped in achieving better history match that ensures reliable production forecast for the stringer sands. The paper comprises the numerical details, comparisons and validation relevant to the study. In addition, production scenarios were evaluated and compared. The rock bodies and higher-order heterogeneity based model revealed that by placing the wells with the adequate orientation and spacing, targeting the sand bodies is paramount to improve the recovery from the field.
A Model of Dynamic Tax Planning with an Application to Estate Freezes
Authors: Klassen Kenneth J. , Sansing Richard C.
Published: December 2011

This paper develops a model of dynamic tax planning in which the implementation of a tax plan involves exercising an option to execute an irreversible investment or financing structure transaction. The model considers four aspects of such transactions and shows that transactions are deferred if the tax savings from the transaction are lower or if the time horizon over which the transaction can be executed is longer. Deferral is also increasing in cost of a future unfavorable event to which the irreversibility of the transaction limits one's ability to respond, but may increase or decrease with a change in the probability that an unfavorable event occurs. We apply the model to a common estate freeze tax plan in Canada. Undertaking an estate freeze requires a private company's owner-manager to choose how one's business assets are to be distributed at death. In contrast to the conventional wisdom regarding the timing of this strategy, we find that waiting to implement the strategy is often optimal. We test the model using data on family-owned businesses in Canada and find strong support for the model's predictions.
Feminine Authorship and Women's Education in Citius, Altius, Fortius Journal (1959-1976)
Authors: Isidori Emanuele , Peña María , Pedraz Miguel
Published: December 2011

Feminine Authorship and Women's Education in Citius, Altius, Fortius Journal (1959-1976)

This article approaches women's scientific and humanistic production in the journal Citius, Altius, Fortius. Based on several previous bibliometric and thematic studies - where the journal's epistemological orientation and ideological and editorial trajectory were analyzed - this research aims to highlight and analyze the role of women who collaborate in the journal in order to set these representations. The article deals particularly with women's conceptions as physical activity practitioners.

Descriptive, comparative and content analysis techniques have been used, emphasizing ideological discourse. In conclusion we point out the disproportion of women's scientific production, which shows males' dominant position in physical activity studies at that time.

The very female authors' perspective about sportswomen is in fact an accommodative, and even a servile, position towards the dominant physicaleducative and sport discourses.
Simplified Model of Road-User Costs for Portuguese Highways
Authors: Santos Bertha Maria Batista dos , de Picado-Santos Luís Guilherme , Cavaleiro Victor Manuel Pissarra
Published: December 2011

When evaluating road design, maintenance, and rehabilitation, the Portuguese Road Administration does not consider road-user costs. A simplified model of road-user costs for highway networks and the selection of input values for Portuguese conditions were defined, with 2006 as the base year for calculations. The steps in defining the model were the analysis of the most important models of current road-user costs to provide the conceptual framework for a simplified and new model; the characterization of Portuguese highways by input data definition; and the inventory of official sources, formulations, and definition directives for input data. With the simplified formulation, user costs can be integrated in management frameworks in an easy, fast, and reliable way. A consideration of extended transport costs (construction, maintenance, and user costs) will allow a more accurate life-cycle economic analysis and will contribute to the sustainability of road infrastructure. Two applications of the model to Portuguese road networks under concession are presented.
Performance Modeling of Infrastructure Condition Data with Maintenance Intervention
Authors: Gao Lu , Aguiar-Moya José Pablo , Zhang Zhanmin
Published: December 2011

Accurate prediction of infrastructure condition is critical to infrastructure management agencies. Reliable and accurate predictions of infrastructure conditions save significant amounts of money for infrastructure management agencies through better planning of maintenance and rehabilitation activities. A good performance model relies heavily on the quality of the data collected and stored in the infrastructure management system. However, records of maintenance treatments are sometimes unavailable in the inventory. As a result, it is difficult to determine if a sudden increase in condition is caused by a maintenance intervention or by random measurement errors. Agencies with this problem usually filter the data set by removing possible outliers, subjecting the data to several quality control checks. For example, the change in condition may be considered a measurement error if the magnitude of the change is less than a given threshold. However, determination of the threshold value is sometimes arbitrary and may lead to bias in the development of performance models. A robust performance modeling technique was developed to address this problem. The proposed methodology captures the infrastructure deterioration rate without filtering of any data points. This method also calculates the probability that a data point is affected by maintenance intervention. Roughness data from the Long-Term Pavement Performance database is used to demonstrate the proposed methodology.
Model of Relationship between Interstate Crash Occurrence and Geometrics
Authors: Venkataraman Narayan S. , Ulfarsson Gudmundur F. , Shankar Venky , Oh Junseok , Park Minho
Published: December 2011

This paper proposes the use of a random parameter negative binomial (NB) model for the analysis of crash counts. With the use of a 9-year, continuous panel of histories of total crash frequencies on Interstate highways in Washington State for 1999 to 2007, a random parameter NB model was estimated to account for parameter correlations, panel effects that contributed to intrasegment temporal variations, and between-site effects. Interstate geometric variables, such as lighting type proportions by length, shoulder width proportions, lane cross-section proportions, and curvature variables, were used in the model specification. Curvature variables included the number of horizontal curves in a segment, the number of vertical curves in a segment, the shortest horizontal curve in a segment length, the largest degree of curvature in a segment, the smallest vertical curve gradient, and the largest vertical curve gradient in a segment. Segments were analyzed at the interchange and the noninterchange levels. A total of 1,153 directional segments of the seven Washington State Inter-states were analyzed. The analysis yielded a statistical model of crash frequency on the basis of 10,377 observations. Several curvature effects were found to be random, which meant that they varied from segment to segment. Although, for example, the numbers of horizontal and vertical curves in a segment were fixed-parameter effects, the largest degree of curvature, as well as the smallest and largest vertical curve gradient variables, were random parameters. The logarithm of average daily travel and the median and point lighting proportions were also found to be random parameters. These results suggested that segment-specific insights into crash frequency occurrence could be improved for appropriate design policy and prioritization.
Safety Performance Functions for Bicycle Crashes in New Zealand and Australia
Authors: Turner Shane , Wood Graham , Hughes Tim , Singh Rohit
Published: December 2011

After decades of decline, recreational and commuter cycling are becoming more popular in many Australasian cities. This renewed popularity is encouraging from the perspectives of sustainable transport and public health. A major concern to governments at all levels, however, is the higher crash risk that cyclists face, compared with drivers or passengers in motor vehicles, particularly when cyclists ride on roads. Transportation professionals should understand the level of risk that cyclists face within various parts of the road network and the measures that can be employed to mitigate that risk. This paper presents research findings from three main safety studies undertaken in New Zealand with the use of data from cities in New Zealand and in Adelaide, Australia. The research involved both generalized linear modeling and before–after, control–impact methods. Across the various studies, crash, traffic, and cycle volumes and layout data were collected for urban road links, traffic signals, and roundabouts. Flow-only models demonstrated a safety-in-numbers effect: crash risk per cyclist was shown to be lower as cycle volumes increased. When other variables were added to the models, it was possible to understand the impact on various crash types of factors such as road section length, motor vehicle speed, visibility, presence and type of cycle facilities, and lane and road width. Before-and-after analysis was employed to help identify the presence of any bias in the sites that had received cycle facilities. Research findings were mixed on the capacity of cycle facilities to improve safety. Well-designed facilities of adequate width and painted with color appeared to perform best.
Characterization of Moisture Transport and Its Effect on Deformations in Jointed Plain Concrete Pavement
Authors: Wei Ya , Hansen Will
Published: December 2011

Many aspects of concrete durability and performance are influenced by moisture conditions in concrete. Although the importance of moisture effect on concrete pavement has been widely recognized, moisture deformations and stresses were usually ignored in pavement analysis because of a lack of comprehensive understanding of moisture transport properties and difficulties in characterizing their magnitudes. Three moisture transport processes and their effects on internal relative humidity distributions along slab depth, thought to be the major factors affecting concrete pavement deformations and stresses, are discussed. The processes are drying shrinkage and associated nonuniform humidity distribution within the top few inches of a slab, self-desiccation caused by hydration and associated uniform humidity distribution within the entire slab cross section, and water absorption caused by capillary suction and associated nonuniform humidity distribution within the bottom portion of the slab. Experiments and simulations showed that the total humidity loss was a result of self-desiccation and external drying; excessive warping in jointed concrete pavement was caused by simultaneous top surface drying and bottom surface water absorption. Pore discontinuity caused capillary suction at the bottom surface to produce a steep moisture gradient and associated moisture warping. A new methodology was proposed for characterizing moisture-related deformations in slab on ground on the basis of a relationship of shrinkage versus relative pore humidity for concrete. This relationship was obtained from autogenous shrinkage results, which related free shrinkage deformations of a concrete to its internal humidity volumetric aggregate concentration. The proposed methodology provides for a simple postprocessing of moisture-related deformations in slabs on grade.
Survey of Models to Locate Sensors to Estimate Traffic Flows
Authors: Gentili Monica , Mirchandani Pitu B.
Published: December 2011

With the advent of intelligent transportation systems, transportation networks have a considerable amount of traffic detectors, and large amounts of streaming data are available to manage and plan a multi-modal network and provide real-time traffic information to travelers. The related problem of optimally locating sensors on the network to estimate flows has been the object of growing interest in the past few years. Available sensors use various technologies and measure different aspects of traffic flows. This paper classifies sensor location problems in the literature in two categories: the sensor location flow-observability problem and the sensor location flow-estimation problem. This paper reviews the existing contributions for the latter of the two problem types and presents a unifying bilevel optimization framework in which the upper level addresses the location decisions and the lower level addresses the estimation variables. Several directions for future research are discussed.
Integrated Traffic–Communication Simulation Evaluation Environment for IntelliDrive Applications Using SAE J2735 Message Sets
Authors: Park Hyungjun , Miloslavov Adelin , Lee Joyoung , Veeraraghavan Malathi , Park Byungkyu , Smith Brian Lee
Published: December 2011

Vehicle-to-vehicle and vehicle-to-infrastructure communications made possible by IntelliDrive will enable new transportation applications and services. To understand and quantify potential benefits from Intelli-Drive applications, these applications should be evaluated before field deployment. An IntelliDrive simulation environment was developed; it replicated precise vehicular movements, incorporated IntelliDrive wireless communications based on wireless access in vehicular environments–dedicated short-range communication standards, and simulated real IntelliDrive message sets defined in the Society of Automotive Engineers J2735 standard. A case study of a prototype lane changing advisory algorithm revealed that communication delays were not likely to be a significant factor and showed maximum delays of only 55 ms for the basic safety message (BSM) and 1.3 ms for the a la carte message (ACM). The probability of successful communication can affect evaluation results. For example, for a lane changing advisory algorithm, the probability of successful transmission of a series of required messages—three BSMs and one ACM—was only 50% when fewer than 120 vehicles were within a communication radius of 50 m. This result implied a significant degradation in algorithm performance. The results demonstrate the feasibility of integrating traffic and communication simulation models and the need to consider both components in IntelliDrive evaluation.
Impact of Bicycle Lane Characteristics on Exposure of Bicyclists to Traffic-Related Particulate Matter
Authors: Kendrick Christine M. , Moore Adam , Haire Ashley , Bigazzi Alexander , Figliozzi Miguel , Monsere Christopher M. , George Linda
Published: December 2011

Bicycling as a mode of transportation is increasingly seen as a healthy alternative to motorized transportation modes. However, in congested urban areas, the health benefits of bicycling can be diminished by the negative health effects associated with inhalation of particulate matter. Particles of small size (ultrafine particles <0.1 μm) are the most harmful, even during short-duration exposure. Because vehicular exhaust is the major source of ultrafine particles, the impact of traffic levels and bicycle lane characteristics on exposure of bicyclists was studied. Ultrafine particle exposure concentrations were compared in two settings: (a) a traditional bicycle lane adjacent to the vehicular traffic lanes and (b) a cycle track design with a parking lane separating bicyclists from vehicular traffic lanes. Traffic measurements were made alongside air quality measurements. The cycle track design mitigated ultrafine particle exposure concentrations for cyclists. Results showed statistically significant differences in terms of exposure levels for the two bike facilities, as well as correlations between traffic levels and exposure level differences. Results also suggested that ultrafine particle levels and spatial distribution were sensitive to proximity to signalized intersections. Findings of this research indicated that, in high traffic areas, bicycle facility design had the potential to lower air pollution exposure levels of bicyclists.
Evaluation of Shared Lane Markings in Cambridge, Massachusetts
Authors: Hunter William W. , Srinivasan Raghavan , Thomas Libby , Martell Carol A. , Seiderman Cara B.
Published: December 2011

Shared lane markings (sharrows) convey the message that motorists and cyclists must share the travel way on which they are operating. The purpose of the markings is to create improved conditions for bicycling by clarifying where cyclists are expected to ride and reminding motorists to expect cyclists on the road. A before–after evaluation was conducted to compare how cyclists and motorists operated on a street with parallel parking in Cambridge, Massachusetts, with no markings versus with sharrows placed 10 ft (3.05 m) from the curb. This evaluation, which was part of a broader FHWA study on sharrows, was intended to help determine whether an alternative to the 11-ft (3.4-m) spacing recommended in the 2009 version of the Manual on Uniform Traffic Control Devices would be effective. Operational and safety measures for bicyclists and motorists were examined. Overall, safety effects appeared to be associated with the installation of the sharrows placed 10 ft (3.05 m) from the curb. Perhaps the most important effect was the 14-in. (36-cm) increase in spacing between motor vehicles in the travel lane and parked motor vehicles when no bicycles were present. This effect increased the operating space for bicyclists. Many variables related to the interaction of bicycles and motor vehicles also showed positive operational and safety effects.
Cyclopiazonic acid attenuates the divalent cations and augments the mRNA level of iNOS in the liver and kidneys of chickens
Authors: Akbari P. , Malekinejad H. , Rahmani F. , Rezabakhsh A. , Fink-Gremmels J.
Published: December 2011

An investigation was carried out into the occurrence of cyclopiazonic acid (CPA) producing fungi, the level of CPA contamination in chickens' diet, CPA effects on serum levels of divalent cations, on nitric oxide (NO) content and mRNA level of inducible nitric oxide synthase (iNOS) in the liver and kidney of chickens, as well as the cellular and molecular pathways of CPA toxicity. Mycological and HPLC analyses were used to determine the mycobiota and CPA level, respectively. The mycological studies revealed that 34.46 and 23.07% of the isolated fungi were Aspergillus flavus and Penicillium cyclopium, respectively. HPLC analyses showed the highest (0.95±0.35 μg/g) and lowest (0.08±0.03 μg/g) levels of CPA in maize and mix diet, respectively. For toxicological studies, male chickens (Ross 308) were assigned to the control and test groups (n=8), which received normal saline and 10, 25 and/or 50 μg/kg CPA for 28 days. The effects of CPA on NO content of the liver and kidneys were determined using the Griess reaction, and the effects on the serum level of divalent cations were established using commercially available kits. The effects of CPA on the mRNA level of iNOS were investigated using RT-PCR. CPA lowered the serum level of divalent cations, while NO contents were enhanced significantly (P<0.05). The mRNA level of iNOS in birds of the CPA test groups showed a reverse relationship with NO increase. These data suggest that CPA producing fungi along with CPA contamination in chickens' diet result in hepatic and renal disorders. Moreover, CPA induced disorders might contribute to the biochemical alterations such as NO increase that is reversely associated with mRNA level of iNOS.
Fortificaciones e implantación romana entre La Serena y la Vega del Guadiana: el Castejón de las Merchanas (Don Benito, Badajoz) y su contexto territorial
Authors: Mayoral Herrera Victorino , Celestino Pérez Sebastián , Salas Tovar Ernesto , Bustamante Álvarez Macarena
Published: December 2011

El Castejón de las Merchanas es un asentamiento fortificado que se localiza en el curso medio del valle del río Guadamez (Don Benito, Badajoz, España), en los límites de la comarca de La Serena. El buen estado de conservación y la monumentalidad de sus restos hacen que una labor exhaustiva de documentación ofrezca un gran caudal de datos sobre su estructura, funcionalidad y posible adscripción cronológica. Los resultados de dicha labor son confrontados con el conocimiento que actualmente se tiene de las llamadas fortificaciones en altura de la Serena, analizándose sus criterios de localización, diseño, técnica constructiva y materiales arqueológicos. Se propone un modelo de control estratégico del territorio y su contextualización en el proceso de «romanización » del suroeste peninsular.
IEEE802.21 Assisted Fast Re-Authentication Scheme over GSABA
Authors: Mussabbir Qazi Bouland , Owens Thomas
Published: December 2011

To satisfy customer demand for a high performance “global” mobility service, network operators are facing the need to evolve to a converged “all-IP” centric heterogeneous access infrastructure. However, the integration of such heterogeneous access networks brings major mobility issues. Dynamic service bootstrapping and authorization mechanisms must be in place to efficiently deploy a mobility service, which will allow only legitimate users to access the service. Authentication, access, and accounting based authentication mechanisms like Extensible Authentication Protocol (EAP) incur signalling overheads due to large Round Trip Times (RTTs). As a result, overall handover latency also increases. A fast re-authentication scheme is presented in this chapter, which utilizes IEEE802.21 Media Independent Handover (MIH) services to minimize the EAP authentication process delays and reduce the overall handover latency. In this way, it is shown that the demands mobility places on availability can broadly be met, leaving only the generic issues of Internet availability.
Forensic Investigative Process for Situational Awareness in Information Security
Authors: Ali Khidir Mohamed , Owens Thomas
Published: December 2011

As a starting point for the development of a common visualization of the forensics process by the members of an investigating team, this chapter provides algorithms that provide guidance and step by step instructions on how to deal with computer forensics and the investigations they carry out. A general introductory overview of computer forensics is provided, and the framework of a forensic investigation is summarized. On the basis of this framework, three algorithms are provided, one for each phase of a forensic investigation, which cover the different aspects of computer forensics and address key elements to be considered when attacked systems are investigated.
Stress Reduction at the Worksite: An Evaluation of Two Methods
Authors: Goodspeed Ronald B. , DeLucia Ann G.
Published: December 2011

Stress is estimated to cost industry between 75 and 100 billion dollars annually as a result of absenteeism, medical claims and diminished productivity. Two types of stress management programs were studied to evaluate their effectiveness at the worksite. The Time-Life Stress Management Program and a Myers-Briggs Personality Type approach were used. The Time-Life program was given to 113 participants, and 35 participated in the Myers-Briggs program. Baseline stress (strain) scores were obtained using a standardized strain survey instrument. Follow-up strain scores were obtained six to eight months after baseline for 62 percent of the individuals. Both groups showed significant reductions in follow-up strain scores when compared to baseline. Reductions in strain were greater in the group with higher baseline strain scores (Time-Life). Worksite stress management programs have the potential to reduce strain among employees for at least six to eight months.
Fitness Awards: Do They Accomplish Their Intended Objectives?
Authors: Corbin Charles B. , Lovejoy Peter Y. , Steingard Paul , Emerson Richard
Published: December 2011

Considerable attention has recently been focused on awards as a means of motivating children and youth to take fitness tests and to become physically active. This research was conducted to determine the number of youth who actually achieve standards for earning the various fitness awards, the extent to which award earners are successful in achieving other recognition for physical performance, and the relative contribution of various fitness components to earning fitness awards. A total of 1,774 youths (1,227 males and 547 females) ranging in age from 14 to 17 served as subjects in the study. Subjects completed items commonly included in national fitness test batteries, as well as a questionnaire indicating the extent of their athletic accomplishments. Results indicate that very few subjects met criteria for earning fitness awards, and those who did meet these criteria also received recognition for success in athletics. Further, those subjects who met award criteria had discriminant function profiles characterized by power, agility, and speed. These profiles were effective in classifying, and thus predicting, which subjects would be successful in earning awards. Questions should be raised about the motivational effectiveness of awards based on exclusive normative standards since these awards go primarily to those with athletic prowess and motor fitness.
Th2 Cytokine Levels Distort the Association of IL-10 and IFN-γwith Allergic Phenotypes
Authors: Zhang Guicheng , Hayden Catherine M. , Goldblatt Jack , Holt Patrick , Le Souëf Peter N.
Published: December 2011

The expression of allergic phenotypes involves complex inter-relationships among several Th2 and Th1 cytokines as well as the regulator cytokine interleukin (IL)-10. These direct or indirect interrelationships may distort the true associations of cytokine responses with these phenotypes. In this study, we aimed to clarify the effects of the regulatory cytokine IL-10 and Th1 cytokine interferon-gamma (IFN-γ) on allergic phenotypes after adjusting for the correlations with Th2 cytokines. After adjusting for Th2 cytokines, IL-10 and IFN-γwere protective against atopy. Adjusted levels of IL-10 and IFN-γstimulated with house-dust mite (HDM) were significantly lower in atopics than non-atopics, for IL-10 adjusting for IL-5 (P=0.002), IL-13 (P=0.012), IL-9 (P=0.016), and IL-4 (P=0.043), and for IFN-γadjusting for IL-5 (P=0.005), IL-13 (P=0.005), and IL-9 (P=0.037). IL-10 and IFN-γlevels stimulated with phytohaemagglutinin (PHA) and staphylococcal enterotoxin B (SEB) exhibited a similar pattern. The adjusted levels of IL-10 and IFN-γstimulated with HDM, PHA or SEB were all significantly negatively correlated with total serum IgE, except for IFN-γstimulated with SEB. Levels of Th2 cytokines distort the associations of IL-10 and IFN-γwith allergic phenotypes. Removing the covariance with Th2 cytokines, both IL-10 and IFN-γwere protective against atopy.
Diagnostic Potential of Distortion Product Otoacoustic Emissions in Noninvasive Assessment of Elevated Intracranial Pressure: Different Patterns of DPOAE Alterations in the Guinea Pig
Authors: Strassen Ulrich , Deppe Christoph , Mees Klaus , Plesnila Nikolaus , Canis Martin , Strieth Sebastian , Olzowy Bernhard
Published: December 2011

Distortion product otoacoustic emissions (DPOAEs) have been proposed for monitoring the intracranial pressure (ICP) noninvasively. Aim of this study was to establish an animal model in the guinea pig for a detailed characterisation of ICP-related DPOAE alterations. In guinea pigs, the ICP was elevated experimentally and the DPOAE levels were continuously monitored. Two different patterns of DPOAE level changes were observed: (1) a decrease of few decibels affecting mainly the frequency = 2 kHz with instant recovery after normalization of ICP, probably related to alterations of middle ear sound transmission; (2) a more pronounced level decrease affecting all frequencies, combined with a second decrease and prolonged recovery after ICP normalization, which might be related to alterations of the cochlear blood flow. Alterations of the levels of DPOAEs might not only provide information about ICP but also indicate critical
ICP-induced reductions of the cochlear and the cerebral perfusion pressure.