Household epidemic models with varying infection response

This paper is concerned with SIR (susceptible--infected--removed) household epidemic models in which the infection response may be either mild or severe, with the type of response also affecting the infectiousness of an individual. Two different models are analysed. In the first model, the infection status of an individual is predetermined, perhaps due to partial immunity, and in the second, the infection status of an individual depends on the infection status of its infector and on whether the individual was infected by a within- or between-household contact. The first scenario may be modelled using a multitype household epidemic model, and the second scenario by a model we denote by the infector-dependent-severity household epidemic model. Large population results of the two models are derived, with the focus being on the distribution of the total numbers of mild and severe cases in a typical household, of any given size, in the event that the epidemic becomes established. The aim of the paper is to investigate whether it is possible to determine which of the two underlying explanations is causing the varying response when given final size household outbreak data containing mild and severe cases. We conduct numerical studies which show that, given data on sufficiently many households, it is generally possible to discriminate between the two models by comparing the Kullback-Leibler divergence for the two fitted models to these data.

Analysis of a stochastic SIR epidemic on a random network incorporating household structure

This paper is concerned with a stochastic SIR (susceptible-infective-removed) model for the spread of an epidemic amongst a population of individuals, with a random network of social contacts, that is also partitioned into households. The behaviour of the model as the population size tends to infinity in an appropriate fashion is investigated. A threshold parameter which determines whether or not an epidemic with few initial infectives can become established and lead to a major outbreak is obtained, as are the probability that a major outbreak occurs and the expected proportion of the population that are ultimately infected by such an outbreak, together with methods for calculating these quantities. Monte Carlo simulations demonstrate that these asymptotic quantities accurately reflect the behaviour of finite populations, even for only moderately sized finite populations. The model is compared and contrasted with related models previously studied in the literature. The effects of the amount of clustering present in the overall population structure and the infectious period distribution on the outcomes of the model are also explored.

Threshold behaviour and final outcome of an epidemic on a random network with household structure

This paper considers a stochastic SIR (susceptible-infective-removed) epidemic model in which individuals may make infectious contacts in two ways, both within 'households' (which for ease of exposition are assumed to have equal size) and along the edges of a random graph describing additional social contacts. Heuristically-motivated branching process approximations are described, which lead to a threshold parameter for the model and methods for calculating the probability of a major outbreak, given few initial infectives, and the expected proportion of the population who are ultimately infected by such a major outbreak. These approximate results are shown to be exact as the number of households tends to infinity by proving associated limit theorems. Moreover, simulation studies indicate that these asymptotic results provide good approximations for modestly-sized finite populations. The extension to unequal sized households is discussed briefly.

Household portfolio allocation, risk attitudes and credit constraints : evidence from the eurozone

Mestrado em Economia Monetária e Financeira

Increasing the value of household appliances by adding a heat pump system

Historically, domestic tasks such as preparing food and washing and drying clothes and dishes were done by hand. In a modern home many of these chores are taken care of by machines such as washing machines, dishwashers and tumble dryers. When the first such machines came on the market customers were happy that they worked at all! Today, the costs of electricity and customers’ environmental awareness are high, so features such as low electricity, water and detergent use strongly influence which household machine the customer will buy. One way to achieve lower electricity usage for the tumble dryer and the dishwasher is to add a heat pump system. The function of a heat pump system is to extract heat from a lower temperature source (heat source) and reject it to a higher temperature sink (heat sink) at a higher temperature level. Heat pump systems have been used for a long time in refrigerators and freezers, and that industry has driven the development of small, high quality, low price heat pump components. The low price of good quality heat pump components, along with an increased willingness to pay extra for lower electricity usage and environmental impact, make it possible to introduce heat pump systems in other household products. However, there is a high risk of failure with new features. A number of household manufacturers no longer exist because they introduced poorly implemented new features, which resulted in low quality and product performance. A manufacturer must predict whether the future value of a feature is high enough for the customer chain to pay for it. The challenge for the manufacturer is to develop and produce a high-performance heat pump feature in a household product with high quality, predict future willingness to pay for it, and launch it at the right moment in order to succeed. Tumble dryers with heat pump systems have been on the market since 2000. Paper I reports on the development of a transient simulation model of a commercial heat pump tumble dryer. The measured and simulated results were compared with good similarity. The influence of the size of the compressor and the condenser was investigated using the validated simulation model. The results from the simulation model show that increasing the cylinder volume of the compressor by 50% decreases the drying time by 14% without using more electricity.  Paper II is a concept study of adding a heat pump system to a dishwasher in order to decrease the total electricity usage. The dishwasher, dishware and water are heated by the condenser, and the evaporator absorbs the heat from a water tank. The majority of the heat transfer to the evaporator occurs when ice is generated in the water tank. An experimental setup and a transient simulation model of a heat pump dishwasher were developed. The simulation results show a 24% reduction in electricity use compared to a conventional dishwasher heated with an electric element. The simulation model was based on an experimental setup that was not optimised. During the study it became apparent that it is possible to decrease electricity usage even more with the next experimental setup.

Evaluation of the environmental benefits of recycling materials in the moving parts of a wind turbine using the life cycle assessment (LCA)

Wind energy is evaluated positively, from the environmental point of view, considering the wind a renewable resource to produce electricity, avoiding the use of fossil resources during operation, but not much has been studied about the impacts associated with the materials of the wind turbines. This study aims to contribute to an improved understanding of the environmental implications of the materials in the moving parts of a wind turbine and how the Eco strategies as recycling are increasingly adopted to ensure the minimization of environmental impacts. First, we investigate the moving parts of a wind turbine highlighting possible hot spots of impacts. Second, we assess the benefit of introducing recycling materials instead of the originals. © Research India Publications.

Iowa City: Apartment & Condominium Recycling, January 30, 2015

The city of Iowa city is continually working to improve the community's recycling services and options. The city services about 15,000 households, single family home and multifamily homes with four units or fewer with curbside pick ups of refuse, dual-stream recycling and yard waste as well as electronics and bulky waste by appointment.

Iowa State Park Recycling Research Study, 2012

The Department of Natural Resources’ mission of “Leading Iowans in caring for our natural resources” provides the framework within which the Iowa State Park Recycling Research Study was conducted. Recycling at home and in places of business is becoming common for most Iowans but recycling is not available in any form at most Iowa State Parks. The Iowa State Park Recycling Research Study was undertaken to determine the amount of solid waste generated, primarily by campground guests, and how much of this waste is locally recyclable. The study also looked at existing solid waste hauling contracts and the location of area recycling centers. Based on data collected, recommendations are made regarding the economic and operational viability of implementing recycling in the eight (8) state parks participating in the study.

2017 GREENWOOD COUNTY RECYCLING COLLECTION SCHEDULE

This is a calendar of the recycling collection days for Greenwood County in 2017.

RECYCLE YOUR CARPET : QUICK AND EASY INSTRUCTIONS FOR RECYCLING CARPET AND PADDING IN LEXINGTON COUNTY

This brochure describes the kinds of carpeting accepted and not accepted at the Lexington County landfill. It also gives the address of the landfill.

South Carolina State Agencies & Colleges/Universities RECYCLING & BUYING RECYCLED Annual Report Fiscal Year 2016

This report provides an overview of the recycling and buying recycled activities of state agencies and colleges/universities for fiscal year 2016

Gender, class and the household economy in Scotland in the ‘Age of affluence’

From early 1950s to the early 1970s Britain is said to have experienced an ‘age of affluence’. Whilst material conditions for many households improved in these decades, this detailed examination of budget management processes shows that for many working-class households, these gains were the product of hard work and careful money management. Using oral history methodology, this thesis explores lived experiences of the household economy to illuminate these qualifications to ‘affluence’. In so doing, this thesis advances analysis which considers the relationship between the macro-level economic conditions of affluence and the everyday economic realities of households in the post-war period. The thesis examines the operation of the household economy and shows how working-class households utilised domestic labour, budgeting, paid work, credit and thrift to make ends meet, as well as to achieve ‘affluence’. Further, by exploring these areas of the household economy, this thesis shows that gendered ideology continued to preserve power and material inequalities between men and women. Although considerable change did occur, particularly involvement in the paid labour market, domestic responsibilities continued to be an important focus of women’s identities and the effective performance of these duties by women remained central to the success of the household. This thesis represents a fresh focus on how the exploration of everyday life, including the salience of ideological continuities in shaping experience, can qualify and refine our understanding of twentieth century economic and social change, and contributes to socio-historical understandings of ‘affluence’ and its intersections with the household, gender, and class.

The influence of particles recycling on the geochemistry of sediments in a large tropical dam lake in the Amazonian region, Brazil

The influence of particles recycling on the geochemistry of sediments in a large tropical dam lake in the Amazonian region, Brazil. Article in Journal of South American Earth Sciences 72 · December 2016 DOI: 10.1016/j.jsames.2016.09.012 1st Rita Fonseca 16.85 · Universidade de Évora 2nd Catarina Pinho 3rd Manuela Oliveira 22.6 · Universidade de Évora Abstract As a result of over-erosion of soils, the fine particles, which contain the majority of nutrients, are easily washed away from soils, which become deficient in a host of components, accumulating in lakes. On one hand, the accumulation of nutrients-rich sediments are a problem, as they affect the quality of the overlying water and decrease the water storage capacity of the system; on the other hand, sediments may constitute an important resource, as they are often extremely rich in organic and inorganic nutrients in readily available forms. In the framework of an extensive work on the use of rock related materials to enhance the fertility of impoverish soils, this study aimed to evaluate the role on the nutrients cycle, of particles recycling processes from the watershed to the bottom of a large dam reservoir, at a wet tropical region under high weathering conditions. The study focus on the mineralogical transformations that clay particles undergo from the soils of the drainage basin to their final deposition within the reservoir and their influence in terms of the geochemical characteristics of sediments. We studied the bottom sediments that accumulate in two distinct seasonal periods in Tucuruí reservoir, located in the Amazonian Basin, Brazil, and soils from its drainage basin. The surface layers of sediments in twenty sampling points with variable depths, are representative of the different morphological sections of the reservoir. Nineteen soil samples, representing the main soil classes, were collected near the margins of the reservoir. Sediments and soils were subjected to the same array of physical, mineralogical and geochemical analyses: (1) texture, (2) characterization and semi-quantification of the clay fraction mineralogy and (3) geochemical analysis of the total concentration of major elements, organic compounds (organic C and nitrogen), soluble fractions of nutrients (P and K), exchangeable fractions (cation exchange capacity, exchangeable bases and acidity) and pH(H2O).

Assessing Household Food Waste in Italy: A Methodology for Detecting Drivers and Quantities

It has been estimated that one third of edible food destined for human consumption is lost or wasted along the food supply chain globally. Much of the waste comes from Global North, where consumers are considered as the bigger contributors. Different studies tried to analyze and estimate the Household Food Waste (HFW), especially in UK and Northern Europe. The result is that accurate studies at national level exist only in UK, Finland and Norway while no such studies are available in Italy, except for survey- based researches. Though, there is a widespread awareness that such methods might be not able to estimate Food Waste. Results emerging from literature clearly suggest that survey estimate inferior amounts of Food Waste as a result, if compared to waste sorting and weighting analysis or to diary studies. The hypothesis that household food waste is under-estimated when gathered through questionnaires has been enquired into. First, a literature review of behavioral economics and heuristics has been proposed; then, a literature review of the sector listing the existing methodologies to gather national data on Household Food Waste has been illustrated. Finally, a pilot experiment to test a mixed methodology is proposed. While literature suggests that four specific cognitive biases might be able to affect the reliability of answers in questionnaires, results of the present experiment clearly indicate that there is a relevant difference between how much the individual thinks to waste and he/she actually does. The result is a mixed methodology based on questionnaire, diary and waste sorting, able to overcome the cons of each single method.

Sustainability analysis in the mining sector: a case study on new recycling technologies for sulphidic mine residues valorisation

Research has demonstrated that mining activities can cause serious impacts on the environment, as well as the surrounding communities, mainly due to the unsafe storage of mine tailings. This research focuses on the sustainability assessment of new technologies for the recovery of metals from mine residues. The assessment consists in the evaluation of the environmental, economic, and social impacts through the Life Cycle based methods: Life Cycle Assessment (LCA), Life Cycle Costing (LCC), and Social Life Cycle Assessment (SLCA). The analyses are performed on the Mondo Minerals bioleaching project, which aim is to recover nickel and cobalt from the Sotkamo and Vuonos mine tailings. The LCA demonstrates that the project contributes to the avoided production of nickel and cobalt concentrates from new resources, hence reducing several environmental impacts. The LCC analysis shows that the company’s main costs are linked to the bioleaching process, caused by electricity consumption and the chemicals used. The SLCA analyses the impacts on three main stakeholder categories: workers, local community, and society. The results demonstrated that a fair salary (or the absence of it) impacts the workers the most, while the local community stakeholder category impacts are related to the access to material resources. The health and safety category is the most impacted category for the society stakeholder. The environmental and economic analyses demonstrate that the recovery of mine tailings may represents a good opportunity for mine companies both to reduce the environmental impacts linked to mine tailings and to increase the profitability. In particular, the project helps reduce the amounts of metals extracted from new resources and demonstrates that the use of the bioleaching technology for the extraction of metals can be economically profitable.