10 research outputs found

    Asset Valuation: A Performance Measure for Comprehensive Infrastructure Asset Management

    Get PDF
    Asset valuation is an essential component of effective asset management. It is an important method to demonstrate proper management of public assets and effective utilization of government’s budgets. Several government regulatory bodies mandate agencies to report their Tangible Capital Assets’ (TCA) values within their annual statement. For example, the Canadian Public Sector Accounting Board (PSAB), the Governmental Accounting Standard Board (GASB) and the New Zealand International Financial Reporting Standards (NZ IFRS), to name a few. Although some limited research has been conducted on incorporating asset value into asset management systems, there is no comprehensive work done to date to incorporate asset valuation in asset management. An integration method is imperative to manage assets in the most optimized cost-effective ways while maintaining or enhancing the value of these assets. Integrating asset value in asset management strengthens the asset management framework by integrating financial and engineering reporting. In addition, agencies have traditionally made investment decisions for individual assets separately. Independent management systems have traditionally been developed to manage assets, in particular pavements and bridges, the two main transportation assets. The lack of integration between management systems may be due to restrictions associated with funding and/or limitations to the agency’s ability to compare data objectively across asset types. Deciding how to best allocate limited resources across these various asset classes to provide acceptable performance poses a persistent and difficult challenge for agencies. Asset value holds a great promise to be incorporated in asset management as a performance measure that translates infrastructure condition in monetary terms that can be easily communicated and understood by the stakeholders (agency, policy makers, users, etc.). Therefore, asset value can be viewed as a common performance measure for integration mechanism between competing asset management systems. vi The objective of this research is to develop a methodology that integrates asset value as a performance measure in asset management decision making. This thesis introduces an asset management methodology that aims to arrive at an optimum value-based asset management plan of maintaining infrastructure assets taking into account budgetary and performance constraints. To achieve this objective, an Asset Value Index (AVI) that integrates asset value and value-driver performance measures and associated thresholds and Level of Service (LOS) requirements is proposed. The Multi-Attribute Utility Theory (MAUT) is used to develop the proposed AVI. In order to incorporate asset value in asset management and develop the AVI, a comprehensive and analytical analysis of various asset valuation methods is conducted. Based on the analysis, challenges of incorporating asset management are identified and addressed by the proposed Asset Value Loss ratio (AVL) as an integration means. To demonstrate the proposed methodology, a case study from the Ministry of Transportation of Ontario (MTO) second generation Pavement Management System (PMS2) is presented. An overview of MTO road assets network is presented and analyzed. In addition, the various components of the proposed methodology are demonstrated through the case study. Furthermore, the outcome of the implementation of the proposed AVI is compared to optimization output, Do-Nothing output as well as needs assessment output. Furthermore, building on the proposed methodology presented, a value-based cross asset management methodology is presented using the AVI as a common integration measure. A case study of pavements and bridges based on data obtained from the 7th International Conference of Managing Pavement Assets (ICMPA 7) is used to illustrate the proposed methodology

    The epidemiology of HIV-1 and other STDs in trucking workers in Kenya: preparations for HIV-1 vaccine trials

    Get PDF
    A cohort of HIV-1 seronegative male trucking company workers was established in the Kenyan coastal city of Mombasa, for the purposes of preparing them for HIV-1 preventive vaccine trials. The cohort was one of only three prospective male cohorts which have published data on heterosexual HIV-1 acquisition in sub-Saharan Africa, the continent most affected by this pandemic. HIV-1 seroincidence was measured and correlates of HIV-1 acquisition, including other STDs, were examined. Results of almost three year's of follow-up, and data on anticipated acceptance of the conditions of an HIV-1 vaccine trial are presented. o The baseline seroprevalence for antibodies to HIV-1 was 17% and the prevalence of active syphilis was 4.5%. o HIV-1 seroincidence was 4.0% per annum in 990 person years of follow-up. Multivariate Hazard analysis revealed a strong association between HIV-1 acquisition and occupation of driver or assistant (HR 4.0, 95% CI: 2.1-7.9), any sex with a partner other than a spouse (HR 4.2, 95% CI: 1.3-13.6), and a trend towards higher incidence with uncircumcised status (HR 2.0, 95% CI: 0.9-4.6). No association between STD and HIV-1 acquisition was found with an observed incidence of symptomatic gonococcal and non-gonococcal urethral discharge of 18.2% per annum, and 4.3% per annum for genital ulcer disease. o There were highly significant declines in extramarital sexual contacts from 50% to 40% in three month follow-up time blocks (p<0.001), and sex worker contacts from 12% to 6% (p=0.001), in a time trends analysis which included 494 person- years of follow-up. No significant change in condom use was recorded over time. Consistent (100%) condom use remained at approximately 30% of men engaging in extramarital sex with a partner other than a spouse. o Highly significant declines in the incidence of observed and reported sexually transmitted diseases were measured over the course of follow-up (p<0.001) in the first 494 person-years of follow-up. In the absence of data from the general population, it is not possible to attribute these declines to the behavioural and treatment interventions of the project, but it does document that the climate is right for behaviour change, and decrease in STD acquisition, in men in this setting. o Prevalence of symptomatic and asymptomatic urethral infections {N gonorrhoeae, C trachomatis, or T vaginalis) was 11.5% in a cross-sectional study which included HIV-1 seropositive men, following the documented decline in symptomatic STDs. Over two thirds of infections were asymptomatic. The leucocyte esterase dipstick (LED) urine screening test for urethral inflammation had a sensitivity of 55% and a specificity of 82%, in asymptomatic men. The LED test was the most accurate predictor of asymptomatic urethral infection. Risk assessment on the basis of demographic and behavioural characteristics did not prove useful. T vaginalis was the most common urethral infection and was associated with older age. o Eighty six per cent of 201 HIV-1 seronegative men interviewed in a vaccine acceptability survey stated that they felt at personal risk of HIV infection, and 84%) of men declared interest in participation in an HIV preventive vaccine trial. However, 17% of men stated that they would increase risk behaviour if they pai'ticipated in an HIV vaccine trial

    Token or full member of the team? : an examination of the utilization and status of women in combat arms positions in the armed forces of Canada, the United Kingdom and the United States of America

    Get PDF
    It is argued in this thesis that because of the androcentric nature of the military institution women in combat arms positions in the armed forces of Canada, the United Kingdom and the United States of America are or will be tokens. In order to investigate and support the hypothesis several areas of literature had to be examined and interviews undertaken with military policy-makers/advisers, recruiters and retired female brigadier generals.Chapter One examines the broad body of literature in the field of military sociology. This chapter details the history of the evolution of the military from a mercenary force to mass armies sustained by conscription through to all-volunteer forces. It also exammes the effect of technology on the military, the changing role of the military in society, and theories of occupationalization versus the institutionalization/professionalization of the armed forces.Chapter Two examines and critiques the notions of inherent female pacifism and inherent male aggression expounded within some of the feminist literature. By detailmg a cross-cultural history of women warriors and female combatants the aforementioned notions are dismissed as untenable. Chapter Three continues with a presentation of the history of the utilization of women in the armed forces of the three countries from their first unofficial presence as "camp-followers" to the present day expanded roles in combat positions.In Chapter Four the theories of tokenism utilized in this thesis are detailed. This chapter presents and assesses the definitions of "token" and "tokenism". A review of the literature of women in male-dominated occupations and women in the military as "tokens" is also undertaken.The fifth chapter details the methodology utilized in this thesis. The fieldwork and questionnaire developmental processes, the interview questionnaires, details of the respondents and the locations of the interviews, and problems encountered in the research are presented.Chapter Six involves a presentation of the results of the interviews with military policymakers/ advisers, recruiters and retired female general officers. The results are presented on a person-by-person basis followed by overall generalizations and generalizations based on country and occupational category all of which provide the impetus for the supporting of the hypothesis.It is in the eighth chapter that theory is applied to practice in that the theories and definitions of tokens and tokenism are applied to the results of the interviews and supplemented by defence document studies to support the hypothesis that because of the androcentric nature of the military institution women in combat arms positions in the armed forces of Canada, the United Kingdom and the United States of America are or will be tokens

    An Annotated Bibliography of Objective Pilot Performance Measures

    Get PDF
    FINAL REPORT - February-September 1981Author William F. Moroney taught at NPS in Operations Research and Naval Aviation Safety. Author Ted R. Mixon was a student in Operations Research.[Robert] Buckout's review in 1962 was the last comprehensive examination of the pilot performance measurement PPM literature. This annotated bibliography attempts to 1 gather the PPM literature written subsequent to 1962 into one source 2 describe the scenarios and measures used in collecting PPM data and 3 summarize the major premises and findings of each article. A variety of sources including computer aided literature search were used to identify candidate articles. Ultimately all referenced material was divided into three categories 1 objective pilot performance measurement 2 subjective pilot performance measures and 3 general analysis and review articles. The objective performance measure category was arranged as follows Field Conditions, Simulator Conditions, Laboratory Conditions, and Combination of Field Conditions, Simulator andor Laboratory Conditions. For each of the objective measure articles reviewed, the following parameters were reported subjects, equipment, scenario, measures and summary. For the subjective measures and general analysis and review articles the authors abstract was generally duplicated. In addition to the 189 articles addressing objective performance measurement, 30 articles dealing with subjective measures and 143 related analyses and review articles are contained in the bibliography.Approved for public release; distribution is unlimited

    Transport demand in China : estimation, projection, and policy assessment

    Get PDF
    Thesis: Ph. D. in Engineering Systems, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, 2018.Cataloged from PDF version of thesis. "Some pages in the original document contain text that runs off the edge of the page"--Disclaimer Notice page.Includes bibliographical references.China's rapid economic growth in the twenty-first century has driven, and been driven by, concomitant motorization and growth of passenger and freight mobility, leading to greater energy demand and environmental impacts. In this dissertation I develop methods to characterize the evolution of passenger transport demand in a rapidly-developing country, in order to support projection and policy assessment. In Essay #1, I study the role that vehicle tailpipe and fuel quality standards ("emissions standards") can play vis-à-vis economy-wide carbon pricing in reducing emissions of pollutants that lead to poor air quality. I extend a global, computable general equilibrium (CGE) model resolving 30 Chinese provinces by separating freight and passenger transport subsectors, road and non-road modes, and household-owned vehicles; and then linking energy demand in these subsectors to a province-level inventory of primary pollutant emissions and future policy targets. While climate policy yields an air quality co-benefit by inducing shifts away from dirtier fuels, this effect is weak within the transport sector. Current emissions standards can drastically reduce transportation emissions, but their overall impact is limited by transport's share in total emissions, which varies across provinces. I conclude that the two categories of measures examined are complementary, and the effectiveness of emissions standards relies on enforcement in removing older, higher-polluting vehicles from the roads. In Essay #2, I characterize Chinese households' demand for transport by estimating the recently-developed, Exact affine Stone index (EASI) demand system on publicly-available data from non-governmental, social surveys. Flexible, EASI demands are particularly useful in China's rapidly-changing economy and transport system, because they capture ways that income elasticities of demand, and household transport budgets, vary with incomes; with population and road network densities; and with the supply of alternative transport modes. I find transport demand to be highly elastic ([epsilon][subscript x] = 1.46) at low incomes, and that income-elasticity of demand declines but remains greater than unity as incomes rise, so that the share of transport in households' spending rises monotonically from 1.6 % to 7.5 %; a wider, yet lower range than in some previous estimates. While no strong effects of city-level factors are identified, these and other non-income effects account for a larger portion of budget share changes than rising incomes. Finally, in Essay #3, I evaluate the predictive performance of the EASI demand system, by testing the sensitivity of model fit to the data available for estimation, in comparison with the less flexible, but widely used, Almost Ideal demand system (AIDS). In rapidly-evolving countries such as China, survey data without nationwide coverage can be used to characterize transport systems, but the omission of cities and provinces could bias results. To examine this possibility, I estimate demand systems on data subsets and test their predictions against observations for the withheld fraction. I find that simple EASI specifications slightly outperform AIDS under cross-validation; these offer a ready replacement in standalone and CGE applications. However, a trade-off exists between accuracy and the inclusion of policy-relevant covariates when data omit areas with high values of these variables. Also, while province-level fixed-effects control for unobserved heterogeneity across units that may bias parameter estimates, they increase prediction error in out-of-sample applications-revealing that the influence of local conditions on household transport expenditure varies significantly across China's provinces. The results motivate targeted transport data collection that better spans variation on city types and attributes; and the validation technique aids transport modelers in designing and validating demand specifications for projection and assessment.by Paul Natsuo Kishimoto.Ph. D. in Engineering System

    Estudio comparativo de biocerámicas de fosfato cálcico para regeneración ósea: efectos de la estructura cristalina y de la micro y nanoporosidad

    Get PDF
    En esta tesis se ha estudiado la influencia de la micro y macroporosidad y de la estructura superficial en biocer√°micas de HA y ő≤-TCP para regeneraci√≥n √≥sea. Se han sintetizado y caracterizado granulados de ambas composiciones qu√≠micas, con densidades del 97% y con porosidad igualada (47%). Estos materiales, Bio-Oss¬ģ y KeraOs¬ģ se han implantado en defectos generados en calotas de conejos. Transcurridas 16 semanas, se ha realizado un an√°lisis histomorfom√©trico del porcentaje de hueso neoformado y de material remanente. Las formas porosas optimizan la neoformaci√≥n √≥sea. La composici√≥n qu√≠mica y la distribuci√≥n de poros intervienen en la formaci√≥n √≥sea, no pudiendo considerarse de forma aislada. Los materiales de ő≤-TCP tienen una tasa de reabsorci√≥n mayor. En la fabricaci√≥n de materiales para regeneraci√≥n √≥sea, hay que adecuar el porcentaje y tama√Īo de poro a la composici√≥n qu√≠mica para que su tasa de reabsorci√≥n est√° acorde con la velocidad de formaci√≥n √≥sea

    GIS based analysis of agricultural biomass

    Get PDF
    Zur Absch√§tzung von regionalen Bioenergiepotenzialen wurden das Biomasse-Ertragsmodell (Biomass Yield Model BYM) entwickelt und in Brandenburg, Deutschland und Europa angewendet. Dazu wurden die erforderlichen Modelleingansparameter (Anbaufl√§chen landwirtschaftlicher Kulturen, Geodaten zum bodenspezifischen Ertragsniveau sowie Niederschlagssummen nach Vegetationszeiten von Winter- und Sommerfr√ľchten) f√ľr die unterschiedlichen Skalenebenen abgeleitet und validiert. Die Potenzialanalysen sind auf eine standortangepasste, nachhaltige Landwirtschaft, den Anbau von regional ausgewogenen Fruchtfolgen und eine ausgeglichene oder positive Humusbilanz ausgerichtet. Unter Ber√ľcksichtigung des regionalen Verbrauchs an Saatgut, Nahrungs- und Futtermitteln werden Bioenergiepotenziale f√ľr Biokraftstoffe, Biogas und landwirtschaftliche Reststoffe regional differenziert modelliert. Es k√∂nnen klimatische und landwirtschaftliche Szenarien sowie Rohstoff-Konkurrenzen im Einzugsbereich der Bioenergieanlagen berechnet und standortspezifisch differenziert visualisiert werden.The biomass yield model BYM was developed to assess regional bioenergy targets and the achievement of which. The model delivers regionally differentiated biomass potentials for biofuel, biogas and agricultural residues. They are aligned to a locally adapted agricultural management systems taking good practice guidelines, regionally adapted crop rotations and humus balances into account. An estimation of regional consumption of seed, food and feed were considered as well. Scenarios enable the visualization of differences in the climatic conditions, agricultural management practices as well as competitive biomass consumption. Additionally, the catchment area of bioenergy plants can be represented. As model input parameters the following were developed and validated at the scales of federal state Brandenburg, Germany and Europe: the acreage of crops, soil productivity level and growing season precipitation of winter and summer crops. The model basic yield functions have been adapted to the precipitation time series
    corecore