A distribuição de riscos em concessões florestais: uma análise econômico-jurídica dos riscos recorrentes do inventário florestal amostral

A Lei 11.284/2006 é um importante marco legal da atividade de gestão florestal do Brasil. O manejo florestal sustentável de florestas públicas, até então exercido exclusivamente pelo Estado, passou a ser passível de concessão com o advento dessa Lei. A chamada “concessão florestal” se insere, portanto, na nova orientação político-econômica brasileira de “desestatização”, privilegiando o princípio da eficiência. Como resultado, a atividade de exploração sustentável de produtos florestais passa a ser transferida pelo Estado, por intermédio do Serviço Florestal Brasileiro, à iniciativa privada. Para o sucesso de uma concessão florestal, os licitantes interessados precisam de uma estimativa da capacidade produtiva da “Unidade de Manejo Florestal”. O estudo disponibilizado pelo Serviço Florestal Brasileiro para fazer essa estimativa é o inventário florestal que, resumidamente, tem a importante missão de antecipar às características vegetais de área que será objeto da concessão. E os resultados desse estudo são a principal fonte de informação para que o licitante calcule o valor que irá ofertar ao Poder Concedente. Ocorre que, por questões técnico-metodológicas que fogem ao conhecimento jurídico, os estudos de inventário florestal estão sujeitos a erros de grande escala, retratando, de maneira ilusória, a realidade da vegetação que compõe área que será concedida. Isto é um risco intrínseco à atividade de exploração sustentável de produtos florestais. Diante desse contexto, caberia ao Serviço Florestal Brasileiro administrar o risco do inventário florestal da maneira mais eficiente possível. Entretanto, não é isso que vem ocorrendo nos contratos de concessão florestal. Sobre a distribuição de riscos em contratos de concessão, a doutrina especializada no tema oferece critérios que, quando seguidos, possibilitam uma alocação dos riscos peculiares a cada atividade à parte que melhor tem condições de geri-los. Esses critérios aumentam a eficiência da concessão. Contudo, os contratos de concessão florestal até hoje celebrados não vêm considerando esses importantes critérios para uma eficiente distribuição de riscos. Como consequência, o risco do inventário florestal é, igualmente a outros inúmeros riscos, negligenciado por esses contratos, aumentando-se a ineficiência dos contratos de concessão. Diante desse panorama, os licitantes interessados na concessão adotam duas posturas distintas, ambas igualmente rejeitáveis: a postura do Licitante Conservador e a postura do Licitante Irresponsável. Esses perfis de licitantes geram, respectivamente, ineficiência à concessão e, caso o erro do inventário florestal efetivamente ocorra, a possibilidade de inviabilidade da concessão. Como resposta a isso – que é exatamente o “problema” que pretendo resolver –, proponho uma solução para melhor administrar o risco do inventário florestal. Essa solução, inspirada em uma ideia utilizada na minuta do contrato de concessão da Linha 4 do Metrô de São Paulo, e baseando-se nos critérios oferecidos pela doutrina para uma distribuição eficiente dos riscos, propõe algo novo: a fim de tornar a os contratos de concessão florestal mais eficientes, sugere-se que o risco do inventário florestal deve ser alocado na Administração Pública, e, caso o evento indesejável efetivamente ocorra (erro do inventário florestal), deve-se, por meio do reequilíbrio econômico-financeiro do contrato, ajustar o valor a ser pago pelo concessionário ao Poder Concedente. Como consequência dessa previsão contratual, as propostas dos licitantes serão mais eficientes, permitindo-se alcançar o objetivo primordial da Lei 11.284/2006: aumento da eficiência da exploração florestal sustentável e preservação do meio ambiente e dos recursos florestais.

Multiple testing in spatial epidemiology: a Bayesian approach

In this work we aim to propose a new approach for preliminary epidemiological studies on Standardized Mortality Ratios (SMR) collected in many spatial regions. A preliminary study on SMRs aims to formulate hypotheses to be investigated via individual epidemiological studies that avoid bias carried on by aggregated analyses. Starting from collecting disease counts and calculating expected disease counts by means of reference population disease rates, in each area an SMR is derived as the MLE under the Poisson assumption on each observation. Such estimators have high standard errors in small areas, i.e. where the expected count is low either because of the low population underlying the area or the rarity of the disease under study. Disease mapping models and other techniques for screening disease rates among the map aiming to detect anomalies and possible high-risk areas have been proposed in literature according to the classic and the Bayesian paradigm. Our proposal is approaching this issue by a decision-oriented method, which focus on multiple testing control, without however leaving the preliminary study perspective that an analysis on SMR indicators is asked to. We implement the control of the FDR, a quantity largely used to address multiple comparisons problems in the eld of microarray data analysis but which is not usually employed in disease mapping. Controlling the FDR means providing an estimate of the FDR for a set of rejected null hypotheses. The small areas issue arises diculties in applying traditional methods for FDR estimation, that are usually based only on the p-values knowledge (Benjamini and Hochberg, 1995; Storey, 2003). Tests evaluated by a traditional p-value provide weak power in small areas, where the expected number of disease cases is small. Moreover tests cannot be assumed as independent when spatial correlation between SMRs is expected, neither they are identical distributed when population underlying the map is heterogeneous. The Bayesian paradigm oers a way to overcome the inappropriateness of p-values based methods. Another peculiarity of the present work is to propose a hierarchical full Bayesian model for FDR estimation in testing many null hypothesis of absence of risk.We will use concepts of Bayesian models for disease mapping, referring in particular to the Besag York and Mollié model (1991) often used in practice for its exible prior assumption on the risks distribution across regions. The borrowing of strength between prior and likelihood typical of a hierarchical Bayesian model takes the advantage of evaluating a singular test (i.e. a test in a singular area) by means of all observations in the map under study, rather than just by means of the singular observation. This allows to improve the power test in small areas and addressing more appropriately the spatial correlation issue that suggests that relative risks are closer in spatially contiguous regions. The proposed model aims to estimate the FDR by means of the MCMC estimated posterior probabilities b i's of the null hypothesis (absence of risk) for each area. An estimate of the expected FDR conditional on data (\FDR) can be calculated in any set of b i's relative to areas declared at high-risk (where thenull hypothesis is rejected) by averaging the b i's themselves. The\FDR can be used to provide an easy decision rule for selecting high-risk areas, i.e. selecting as many as possible areas such that the\FDR is non-lower than a prexed value; we call them\FDR based decision (or selection) rules. The sensitivity and specicity of such rule depend on the accuracy of the FDR estimate, the over-estimation of FDR causing a loss of power and the under-estimation of FDR producing a loss of specicity. Moreover, our model has the interesting feature of still being able to provide an estimate of relative risk values as in the Besag York and Mollié model (1991). A simulation study to evaluate the model performance in FDR estimation accuracy, sensitivity and specificity of the decision rule, and goodness of estimation of relative risks, was set up. We chose a real map from which we generated several spatial scenarios whose counts of disease vary according to the spatial correlation degree, the size areas, the number of areas where the null hypothesis is true and the risk level in the latter areas. In summarizing simulation results we will always consider the FDR estimation in sets constituted by all b i's selected lower than a threshold t. We will show graphs of the\FDR and the true FDR (known by simulation) plotted against a threshold t to assess the FDR estimation. Varying the threshold we can learn which FDR values can be accurately estimated by the practitioner willing to apply the model (by the closeness between\FDR and true FDR). By plotting the calculated sensitivity and specicity (both known by simulation) vs the\FDR we can check the sensitivity and specicity of the corresponding\FDR based decision rules. For investigating the over-smoothing level of relative risk estimates we will compare box-plots of such estimates in high-risk areas (known by simulation), obtained by both our model and the classic Besag York Mollié model. All the summary tools are worked out for all simulated scenarios (in total 54 scenarios). Results show that FDR is well estimated (in the worst case we get an overestimation, hence a conservative FDR control) in small areas, low risk levels and spatially correlated risks scenarios, that are our primary aims. In such scenarios we have good estimates of the FDR for all values less or equal than 0.10. The sensitivity of\FDR based decision rules is generally low but specicity is high. In such scenario the use of\FDR = 0:05 or\FDR = 0:10 based selection rule can be suggested. In cases where the number of true alternative hypotheses (number of true high-risk areas) is small, also FDR = 0:15 values are well estimated, and \FDR = 0:15 based decision rules gains power maintaining an high specicity. On the other hand, in non-small areas and non-small risk level scenarios the FDR is under-estimated unless for very small values of it (much lower than 0.05); this resulting in a loss of specicity of a\FDR = 0:05 based decision rule. In such scenario\FDR = 0:05 or, even worse,\FDR = 0:1 based decision rules cannot be suggested because the true FDR is actually much higher. As regards the relative risk estimation, our model achieves almost the same results of the classic Besag York Molliè model. For this reason, our model is interesting for its ability to perform both the estimation of relative risk values and the FDR control, except for non-small areas and large risk level scenarios. A case of study is nally presented to show how the method can be used in epidemiology.

Evaluación de la distribución de riesgos en los distintos modelos de asociación público-privada para la provisión de infraestructura carretera en México

México es de los pocos países en el mundo que ha realizado dos grandes programas para la construcción de autopistas en colaboración con el sector privado. El primero, fue realizado entre 1989 y 1994, con resultados adversos por el mal diseño del esquema de concesiones; y, el segundo con mejores resultados, en operación desde 2003 mediante nuevos modelos de asociación público-privada (APP). El objetivo de la presente investigación es estudiar los modelos de asociación público-privada empleados en México para la provisión de infraestructura carretera, realizando el análisis y la evaluación de la distribución de riesgos entre el sector público y privado en cada uno de los modelos con el propósito de establecer una propuesta de reasignación de riesgos para disminuir el costo global y la incertidumbre de los proyectos. En la primera parte se describe el estado actual del conocimiento de las asociaciones público-privadas para desarrollar proyectos de infraestructura, incluyendo los antecedentes, la definición y las tipologías de los esquemas APP, así como la práctica internacional de programas como el modelo británico Private Finance Initiative (PFI), resultados de proyectos en la Unión Europea y programas APP en otros países. También, se destaca la participación del sector privado en el financiamiento de la infraestructura del transporte de México en la década de 1990. En los capítulos centrales se aborda el estudio de los modelos APP que se han utilizado en el país en la construcción de la red de carreteras de alta capacidad. Se presentan las características y los resultados del programa de autopistas 1989-94, así como el rescate financiero y las medidas de reestructuración de los proyectos concesionados, aspectos que obligaron a las autoridades mexicanas a cambiar la normatividad para la aprobación de los proyectos según su rentabilidad, modificar la legislación de caminos y diseñar nuevos esquemas de colaboración entre el gobierno y el sector privado. Los nuevos modelos APP vigentes desde 2003 son: nuevo modelo de concesiones para desarrollar autopistas de peaje, modelo de proyectos de prestación de servicios (peaje sombra) para modernizar carreteras existentes y modelo de aprovechamiento de activos para concesionar autopistas de peaje en operación a cambio de un pago. De estos modelos se realizaron estudios de caso en los que se determinan medidas de desempeño operativo (niveles de tráfico, costos y plazos de construcción) y rentabilidad financiera (tasa interna de retorno y valor presente neto). En la última parte se efectúa la identificación, análisis y evaluación de los riesgos que afectaron los costos, el tiempo de ejecución y la rentabilidad de los proyectos de ambos programas. Entre los factores de riesgo analizados se encontró que los más importantes fueron: las condiciones macroeconómicas del país (inflación, producto interno bruto, tipo de cambio y tasa de interés), deficiencias en la planificación de los proyectos (diseño, derecho de vía, tarifas, permisos y estimación del tránsito) y aportaciones públicas en forma de obra. Mexico is one of the few countries in the world that has developed two major programs for highway construction in collaboration with the private sector. The first one was carried out between 1989 and 1994 with adverse outcomes due to the wrong design of concession schemes; and, the second one, in operation since 2003, through new public-private partnership models (PPPs). The objective of this research is to study public-private partnership models used in Mexico for road infrastructure provision, performing the analysis and evaluation of risk’s distribution between the public and the private sector in each model in order to draw up a proposal for risk’s allocation to reduce the total cost and the uncertainty of projects. The first part describes the current state of knowledge in public-private partnership to develop infrastructure projects, including the history, definition and types of PPP models, as well as international practice of programs such as the British Private Finance Initiative (PFI) model, results in the European Union and PPP programs in other countries. Also, it stands out the private sector participation in financing of Mexico’s transport infrastructure in 1990s. The next chapters present the study of public-private partnerships models that have been used in the country in the construction of the high capacity road network. Characteristics and outcomes of the highway program 1989-94 are presented, as well as the financial bailout and restructuring measures of the concession projects, aspects that forced the Mexican authorities to change projects regulations, improve road’s legislation and design new schemes of cooperation between the Government and the private sector. The new PPP models since 2003 are: concession model to develop toll highways, private service contracts model (shadow toll) to modernize existing roads and highway assets model for the concession of toll roads in operation in exchange for a payment. These models were analyzed using case studies in which measures of operational performance (levels of traffic, costs and construction schedules) and financial profitability (internal rate of return and net present value) are determined. In the last part, the analysis and assessment of risks that affect costs, execution time and profitability of the projects are carried out, for both programs. Among the risk factors analyzed, the following ones were found to be the most important: country macroeconomic conditions (inflation, gross domestic product, exchange rate and interest rate), deficiencies in projects planning (design, right of way, tolls, permits and traffic estimation) and public contributions in the form of construction works.

Gender and health inequalities: intersections with other relevant axes of oppression

The risk of disease, disability, and mortality as well as access to health services are unfairly distributed among the population, with certain groups bearing an unequally larger burden of ill health and poorer access to care due to gender, sexual identity/orientation, ethnic background, or class. According to the WHO Commission on Social Determinants of Health (CSDH), these health inequalities emanate from socioeconomic and political factors (governance, cultural values, macroeconomic policies), which generate a set of socioeconomic positions in society according to which populations are stratified based on gender, ethnicity, education, income, or other factors. These societal inequalities influence people’s material and psychosocial circumstances as well as behavioral and biological factors, which in turn impact on health inequalities. Tackling gender, race/ethnic, and socioeconomic inequalities in society is thus recognized as the most powerful action to cope with unequal health risks distribution, and social innovations focusing on these ‘root causes’ are needed in order to prevent and stop endemic social inequalities and social exclusion in health within low-income as well as high-income countries. Increasing existing knowledge and making visible the health status of the most vulnerable and invisible groups are critical in order to contribute to this imperative challenge.

Transfer, distribution and bioaccumulation of microcystins in the aquatic food web in Lake Taihu, China, with potential risks to human health

In this paper, accumulation and distribution of microcystins (MCs) was examined monthly in six species of fish with different trophic levels in Meiliang Bay, Lake Taihu, China, from June to November 2005, Microcystins were analyzed by liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS). Average recoveries of spiked fish samples were 67.7% for MC-RR, 85.3% for MC-YR, and 88.6% for MC-LR. The MCs (MC-RR+MC-YR+MC-LR) concentration in liver and gut content was highest in phytoplanktivorous fish, followed by omnivorous fish, and was lowest in carnivorous fish; while MCs concentration in muscle was highest in omnivorous fish, followed by phytoplanktivorous fish, and was lowest in carnivorous fish. This is the first study reporting MCs accumulation in the gonad of fish in field. The main uptake of MC-YR in fish seems to be through the gills from the dissolved MCs. The WHO limit for tolerable daily intake was exceeded only in common carp muscle. (C) 2008 Elsevier B.V. All rights reserved.

Distribution and bioaccumulation of microcystins in water columns: A systematic investigation into the environmental fate and the risks associated with microcystins in Meiliang Bay, Lake Taihu

For the purpose of understanding the environmental fate of microcystins (MCs) and the potential health risks caused by toxic cyanobacterial blooms in Lake Taihu, a systematic investigation was carried out from February 2005 to January 2006. The distribution of MCs in the water column, and toxin bioaccumulations in aquatic organisms were surveyed. The results suggested that Lake Taihu is heavily polluted during summer months by toxic cyanobacterial blooms (with a maximum biovolume of 6.7 x 10(8) cells/L) and MCs. The maximum concentration of cell-bound toxins was 1.81 mg/g (DW) and the dissolved MCs reached a maximum level of 6.69 mu g/L. Dissolved MCs were always found in the entire water column at all sampling sites throughout the year. Our results emphasized the need for tracking MCs not only in the entire water column but also at the interface between water and sediment. Seasonal changes of MC concentrations in four species of hydrophytes (Eichhornic crassipes, Potamogeton maackianus, Alternanthera philoxeroides and Myriophyllum spicatum) ranged from 129 to 1317, 147 to 1534, 169 to 3945 and 124 to 956 ng/g (DW), respectively. Toxin accumulations in four aquatic species (Carassius auratus auratu, Macrobrachium nipponensis, Bellamya aeruginosa and Cristaria plicata) were also analyzed. Maximum toxin concentrations in the edible organs and non-edible visceral organs ranged from 378 to 730 and 754 to 3629 ng/g (DW), respectively. Based on field studies in Lake Taihu, risk assessments were carried out, taking into account the WHO guidelines and the tolerable daily intake (TDI) for MCs. Our findings suggest that the third largest lake in China poses serious health threats when serving as a source of drinking water and for recreational use. In addition, it is likely to be unsafe to consume aquatic species harvested in Lake Taihu due to the high-concentrations of accumulated MCs. (C) 2007 Elsevier Ltd. All rights reserved.

Choosing a random distribution with prescribed risks

We describe several simulation algorithms that yield random probability distributions with given values of risk measures. In case of vanilla risk measures, the algorithms involve combining and transforming random cumulative distribution functions or random Lorenz curves obtained by simulating rather general random probability distributions on the unit interval. A new algorithm based on the simulation of a weighted barycentres array is suggested to generate random probability distributions with a given value of the spectral risk measure.

Distribution of major health risks: findings from the global burden of disease study

Background Most analyses of risks to health focus on the total burden of their aggregate effects. The distribution of risk-factor-attributable disease burden, for example by age or exposure level, can inform the selection and targeting of specific interventions and programs, and increase cost-effectiveness. Methods and Findings For 26 selected risk factors, expert working groups conducted comprehensive reviews of data on risk-factor exposure and hazard for 14 epidemiological subregions of the world, by age and sex. Age-sex-subregion-population attributable fractions were estimated and applied to the mortality and burden of disease estimates from the World Health Organization Global Burden of Disease database. Where possible, exposure levels were assessed as continuous measures, or as multiple categories. The proportion of risk-factor-attributable burden in different population subgroups, defined by age, sex, and exposure level, was estimated. For major cardiovascular risk factors (blood pressure, cholesterol, tobacco use, fruit and vegetable intake, body mass index, and physical inactivity) 43%-61% of attributable disease burden occurred between the ages of 15 and 59 y, and 87% of alcohol-attributable burden occurred in this age group. Most of the disease burden for continuous risks occurred in those with only moderately raised levels, not among those with levels above commonly used cut-points, such as those with hypertension or obesity. Of all disease burden attributable to being underweight during childhood, 55% occurred among children 1-3 standard deviations below the reference population median, and the remainder occurred among severely malnourished children, who were three or more standard deviations below median. Conclusions Many major global risks are widely spread in a population, rather than restricted to a minority. Population-based strategies that seek to shift the whole distribution of risk factors often have the potential to produce substantial reductions in disease burden.

A disztribúció kiszervezéséhez kapcsolódó ellátási és működési kockázatok (Supply and operational risks in the outsourcing of distribution management)

A cikk célja, hogy elemző bemutatását adja az ellátási láncok működéséhez, különösen a disztribúciós tevékenység kiszervezéséhez kapcsolódó működési kockázatoknak. Az írás első része az irodalomkutatás eredményeit feldolgozva az ellátási láncok kockázati kitettségének növekedése mögött rejlő okokat törekszik feltárni, s röviden bemutatja a vállalati kockázatkezelés lehetséges lépéseit e téren. A cikk második gondolati egysége mélyinterjúk segítségével összefoglalja és rendszerezi a disztribúció kiszervezéséhez kapcsolódó kockázatokat, számba veszi a kapcsolódó kockázatkezelési lehetőségeket, s bemutatja a megkérdezett vállalatok által alkalmazott kockázat-megelőzési alternatívákat. ______ The aim of this paper is to introduce operational risks of supply chains, especially risks deriving from the outsourcing of distribution management. Based on literature review the first part of the paper talks about the potential reasons of increasing global supply chain risks, and the general business activities of risk assessment. Analyzing the results of semi-structured qualitative interviews, the second part summarizes the risks belonging to the outsourcing of distribution and introduces the potential risk assessment and avoidance opportunities and alternatives in practice.

The development of ground impact models for the analysis of the risks associated with Unmanned Aircraft Operations over inhabited areas

With the emergence of Unmanned Aircraft Systems (UAS) there is a growing need for safety standards and regulatory frameworks to manage the risks associated with their operations. The primary driver for airworthiness regulations (i.e., those governing the design, manufacture, maintenance and operation of UAS) are the risks presented to people in the regions overflown by the aircraft. Models characterising the nature of these risks are needed to inform the development of airworthiness regulations. The output from these models should include measures of the collective, individual and societal risk. A brief review of these measures is provided. Based on the review, it was determined that the model of the operation of an UAS over inhabited areas must be capable of describing the distribution of possible impact locations, given a failure at a particular point in the flight plan. Existing models either do not take the impact distribution into consideration, or propose complex and computationally expensive methods for its calculation. A computationally efficient approach for estimating the boundary (and in turn area) of the impact distribution for fixed wing unmanned aircraft is proposed. A series of geometric templates that approximate the impact distributions are derived using an empirical analysis of the results obtained from a 6-Degree of Freedom (6DoF) simulation. The impact distributions can be aggregated to provide impact footprint distributions for a range of generic phases of flight and missions. The maximum impact footprint areas obtained from the geometric template are shown to have a relative error of typically less than 1% compared to the areas calculated using the computationally more expensive 6DoF simulation. Computation times for the geometric models are on the order of one second or less, using a standard desktop computer. Future work includes characterising the distribution of impact locations within the footprint boundaries.

Assessing of circuit breaker restrike risks using computer simulation and wavelet analysis

A breaker restrike is an abnormal arcing phenomenon, leading to a possible breaker failure. Eventually, this failure leads to interruption of the transmission and distribution of the electricity supply system until the breaker is replaced. Before 2008, there was little evidence in the literature of monitoring techniques based on restrike measurement and interpretation produced during switching of capacitor banks and shunt reactor banks in power systems. In 2008 a non-intrusive radiometric restrike measurement method and a restrike hardware detection algorithm were developed by M.S. Ramli and B. Kasztenny. However, the limitations of the radiometric measurement method are a band limited frequency response as well as limitations in amplitude determination. Current restrike detection methods and algorithms require the use of wide bandwidth current transformers and high voltage dividers. A restrike switch model using Alternative Transient Program (ATP) and Wavelet Transforms which support diagnostics are proposed. Restrike phenomena become a new diagnostic process using measurements, ATP and Wavelet Transforms for online interrupter monitoring. This research project investigates the restrike switch model Parameter „A. dielectric voltage gradient related to a normal and slowed case of the contact opening velocity and the escalation voltages, which can be used as a diagnostic tool for a vacuum circuit-breaker (CB) at service voltages between 11 kV and 63 kV. During current interruption of an inductive load at current quenching or chopping, a transient voltage is developed across the contact gap. The dielectric strength of the gap should rise to a point to withstand this transient voltage. If it does not, the gap will flash over, resulting in a restrike. A straight line is fitted through the voltage points at flashover of the contact gap. This is the point at which the gap voltage has reached a value that exceeds the dielectric strength of the gap. This research shows that a change in opening contact velocity of the vacuum CB produces a corresponding change in the slope of the gap escalation voltage envelope. To investigate the diagnostic process, an ATP restrike switch model was modified with contact opening velocity computation for restrike waveform signature analyses along with experimental investigations. This also enhanced a mathematical CB model with the empirical dielectric model for SF6 (sulphur hexa-fluoride) CBs at service voltages above 63 kV and a generalised dielectric curve model for 12 kV CBs. A CB restrike can be predicted if there is a similar type of restrike waveform signatures for measured and simulated waveforms. The restrike switch model applications are used for: computer simulations as virtual experiments, including predicting breaker restrikes; estimating the interrupter remaining life of SF6 puffer CBs; checking system stresses; assessing point-on-wave (POW) operations; and for a restrike detection algorithm development using Wavelet Transforms. A simulated high frequency nozzle current magnitude was applied to an Equation (derived from the literature) which can calculate the life extension of the interrupter of a SF6 high voltage CB. The restrike waveform signatures for a medium and high voltage CB identify its possible failure mechanism such as delayed opening, degraded dielectric strength and improper contact travel. The simulated and measured restrike waveform signatures are analysed using Matlab software for automatic detection. Experimental investigation of a 12 kV vacuum CB diagnostic was carried out for the parameter determination and a passive antenna calibration was also successfully developed with applications for field implementation. The degradation features were also evaluated with a predictive interpretation technique from the experiments, and the subsequent simulation indicates that the drop in voltage related to the slow opening velocity mechanism measurement to give a degree of contact degradation. A predictive interpretation technique is a computer modeling for assessing switching device performance, which allows one to vary a single parameter at a time; this is often difficult to do experimentally because of the variable contact opening velocity. The significance of this thesis outcome is that it is a non-intrusive method developed using measurements, ATP and Wavelet Transforms to predict and interpret a breaker restrike risk. The measurements on high voltage circuit-breakers can identify degradation that can interrupt the distribution and transmission of an electricity supply system. It is hoped that the techniques for the monitoring of restrike phenomena developed by this research will form part of a diagnostic process that will be valuable for detecting breaker stresses relating to the interrupter lifetime. Suggestions for future research, including a field implementation proposal to validate the restrike switch model for ATP system studies and the hot dielectric strength curve model for SF6 CBs, are given in Appendix A.

A recommendation system for predicting risks across multiple business process instances

This paper proposes a recommendation system that supports process participants in taking risk-informed decisions, with the goal of reducing risks that may arise during process execution. Risk reduction involves decreasing the likelihood and severity of a process fault from occurring. Given a business process exposed to risks, e.g. a financial process exposed to a risk of reputation loss, we enact this process and whenever a process participant needs to provide input to the process, e.g. by selecting the next task to execute or by filling out a form, we suggest to the participant the action to perform which minimizes the predicted process risk. Risks are predicted by traversing decision trees generated from the logs of past process executions, which consider process data, involved resources, task durations and other information elements like task frequencies. When applied in the context of multiple process instances running concurrently, a second technique is employed that uses integer linear programming to compute the optimal assignment of resources to tasks to be performed, in order to deal with the interplay between risks relative to different instances. The recommendation system has been implemented as a set of components on top of the YAWL BPM system and its effectiveness has been evaluated using a real-life scenario, in collaboration with risk analysts of a large insurance company. The results, based on a simulation of the real-life scenario and its comparison with the event data provided by the company, show that the process instances executed concurrently complete with significantly fewer faults and with lower fault severities, when the recommendations provided by our recommendation system are taken into account.

Volatile organic compounds: Characteristics, distribution and sources in urban schools

Long term exposure to organic pollutants, both inside and outside school buildings may affect children’s health and influence their learning performance. Since children spend significant amount of time in school, air quality, especially in classrooms plays a key role in determining the health risks associated with exposure at schools. Within this context, the present study investigated the ambient concentrations of Volatile Organic Compounds (VOCs) in 25 primary schools in Brisbane with the aim to quantify the indoor and outdoor VOCs concentrations, identify VOCs sources and their contribution, and based on these; propose mitigation measures to reduce VOCs exposure in schools. One of the most important findings is the occurrence of indoor sources, indicated by the I/O ratio >1 in 19 schools. Principal Component Analysis with Varimax rotation was used to identify common sources of VOCs and source contribution was calculated using an Absolute Principal Component Scores technique. The result showed that outdoor 47% of VOCs were contributed by petrol vehicle exhaust but the overall cleaning products had the highest contribution of 41% indoors followed by air fresheners and art and craft activities. These findings point to the need for a range of basic precautions during the selection, use and storage of cleaning products and materials to reduce the risk from these sources.

Compliance with seafood safety standards within the Vietnamese finfish capture distribution chain

This thesis examined the level of food safety compliance with government regulations and investigated routes of microbiological contaminations in raw finfish within Vietnamese domestic seafood distribution chains. Findings from direct observation, microbiological analysis and employee surveys were synthesized to identify the main factors affecting food safety and hygiene practices of fish distributors. The studies produced clear recommendations for food safety management in the domestic distribution chains. The findings may contribute to national efforts to decrease the risks of fish-borne illness for consumers in Vietnam.