Analysis of Selective Laser Sintering print parameter modelling methodologies for energy input minimisation : a thesis presented in partial fulfilment of the requirements for the degree of Master of Engineering in Mechatronics at Massey University, Albany, New Zealand

Additive Manufacturing (AM) is the name given to a series of processes used to create solids, layer upon layer, from 3 Dimensional (3D) models. As AM experiences rapid growth there exists an opportunity for Selective Laser Sintering (SLS) to expand into markets it has not previously accommodated. One of the ways SLS can accomplish this is by expanding the range of materials that can be processed into useful products, as currently only a small number of materials are available when compared to other AM technologies. One of the biggest barriers to the adoption of materials is the danger inherent to high-energy processes such as SLS. The aim of this research was to identify opportunities to improve current methods for modelling the relationship between material specifications, and printing parameters. This was achieved by identifying existing models used to determine printing parameters for a new material, identifying weaknesses in current modelling processes, conducting experimentation to explore the validity of these weaknesses, and exploring opportunities to improve the model to address these weaknesses. The current models to determine printer parameters to achieve successful sintering include both the Sintering Window (SW) and the Energy Melt Ratio (EMR). These two models are complementary, and both are required to establish all common print parameters. They include both thermal and physical powder properties, but do not include any optical properties. This is significant because the nature of the SLS printing process relies on concentrated delivery of laser energy to achieve successful sintering. Analysis of two similar polyamide powders, one black and one white, identified that the two powders were similar thermally and physically, which meant the models predicted that they should both sinter successfully utilizing the same set of print parameters. Results of the experimental trials showed that no trials involving the white powder sintered successfully, and trials involving the black powder suffered from issues with either insufficient energy to successfully remove parts without damage, or excessive energy causing excess powder to bond to the part. Further experimentation was carried out to investigate the differences in optical properties using Fourier Transform Infrared Spectroscopy (FTIR) and Spectrofluorophotometry. FTIR revealed that there was a difference in absorption as a material property, indicating that differences in laser energy absorption could explain the results seen in the trials. Spectrofluorophotometry revealed minimal differences in fluorescence of the powders, suggesting it an unlikely source of energy loss. Future work is recommended to research a standardised form of testing setup that can be used to categorize the reflectance of a material, as current work relies on proprietary experimental setups. Finding methods of classifying the laser absorption that is easily available to operators would enable refinement of the EMR equation to reflect the energy losses during printing, and remove another barrier for adoption of new materials

Social exclusion and land administration in Orissa, India

The authors report on the first empirical study of its kind to examine - from the perspective of transaction costs - factors that constrain access to land for the rural poor and other socially excluded groups in India. They find that: a) Land reform has reduced large landholdings since the 1950s. Medium size farms have gained most. Formidable obstacles still prevent the poor from gaining access to land. b) The complexity of land revenue administration in Orissa is partly the legacy of distinctly different systems, which produced more or less complete and accurate land records. These not-so-distant historical records can be important in resolving contemporary land disputes. c) Orissa tried legally to abolish land-leasing. Concealed tenancy persisted, with tenants having little protection under the law. d) Women's access to and control over land, and their bargaining power with their husbands about land, may be enhanced through joint land titling, a principle yet to be realized in Orissa. e) Land administration is viewed as a burden on the state rather than a service, and land records and registration systems are not coordinated. Doing so will improve rights for the poor and reduce transaction costs - but only if the system is transparent and the powerful do not retain the leverage over settlement officers that has allowed land grabs. Land in Orissa may be purchased, inherited, rented (leased), or - in the case of public land and the commons - encroached upon. Each type of transaction - and the State's response, through land law and administration - has implications for poor people's access to land. The authors find that: 1) Land markets are thin and transaction costs are high, limiting the amount of agricultural land that changes hands. 2) The fragmentation of landholdings into tiny, scattered plots is a brake on agricultural productivity, but efforts to consolidate land may discriminate against the rural poor. Reducing transaction costs in land markets will help. 3) Protecting the rural poor's rights of access to common land requires raising public awareness and access to information. 4) Liberalizing land-lease markets for the rural poor will help, but only if the poor are ensured access to institutional credit.Banks&Banking Reform,Public Sector Management and Reform,Environmental Economics&Policies,Land Use and Policies,Urban Governance and Management,Public Sector Management and Reform,Environmental Economics&Policies,Banks&Banking Reform,Rural Land Policies for Poverty Reduction,Land Use and Policies

The emotional decision maker: Exploring the role of affect in sweet-food choice

Obesity is now described as a pandemic (Hu, 2013) and a strong association has been identified between sugar consumption and excessive weight gain (e.g. Te Morenga, Mallard & Mann, 2013). Yet difficulty in establishing the factors driving this relationship leaves a dearth of research investigating causal mechanisms behind this global crisis (Lean, Astrup & Roberts, 2018). Food choice has been linked with cognitive processes involved in decision making (Peters, 2009), which in turn, has been linked with affect, i.e. mood and emotion (Lerner, Li, Valdesolo & Kassam, 2015). The aim of this thesis was therefore to explore the way in which both state and trait affect influence impulsive, sweet food decision making across three studies. As hypothesised and supported by affective regulation theory (Gross, 1998), results showed that as laboratory-induced mood (i.e. state affect) moved from positive to negative, the likelihood of choosing a chocolate reward over a non-food/neutral reward increased. This finding was conclusively evident when controlling for other factors such as chocolate craving in Study 2, ultimately highlighting the complex influence of affect on sweet food choice. Following this initial choice in Studies 1 and 2, subsequent hypotheses concerning impulse and self-control were not wholly supported as participants in both mood conditions were more likely to make impulsive decisions than exercise self-control. While affective regulation theory also explained those in negative moods making impulsive choices, an integrative framework was put forward to explain those in positive moods displaying the same behaviour (Andrade, 2005). In Studies 2 and 3 a willingness-to-pay (WTP) task was included to explore the relationship between state and trait affect and economic decisions concerning chocolate and high-sugar foods. While laboratory-induced mood did not predict WTP prices in Study 2, decreasing positive affectivity (i.e. trait affect) was found to significantly predict higher WTP prices for chocolate and high-sugar items, as hypothesised in Study 3. Reduced positive affectivity has been linked with symptoms of depression (Watson, Clark & Carey, 1988) which, in turn, is associated with an increase in desire for chocolate and sweet foods (Lester & Bernard, 1991). These results therefore provided robust evidence that higher spending for sweet items is connected to the absence of positive affectivity rather than presence of negative affectivity. Finally, increasing chocolate craving was found to significantly predict choices and increasing WTP prices for chocolate items in Studies 2 and 3. The potential parallel between chocolate and substances more commonly associated with addiction is discussed, together with the broad, practical implications of all findings in the context of sweet food choice and obesity

CARMA : complete autonomous responsible management agent (system)

University of Technology, Sydney. Faculty of Engineering and Information Technology.The continuing expansion of telecommunication service domains, from Quality of Service guaranteed connectivity to ubiquitous cloud environments, has introduced an ever increasing level of complexity in the field of service management. This complexity arises not only from the sheer variability in service requirements but also through the required but ill-defined interaction of multiple organisations and providers. As a result of this complexity and variability, the provisioning and performance of current services is adversely affected, often with little or no accountability to the users of the service. This exposes a need for total coverage in the management of such complex services, a system which provides for service responsibility. Service responsibility is defined as the provisioning of service resilience and the judgement of service risk across all the service components. To be effective in responsible management for current complex services, any framework must be able to interact with multiple providers and management systems. The CARMA framework proposed by this thesis, aims to fulfil these requirements through a multi-agent system, that is based in a global market, and can negotiate and be responsible for multiple complex services. The research presented in this thesis draws upon previous research in the fields of Network Management and Cloud service management, and utilises agent technology to build a system that is capable of providing resilient and risk aware management of services comprised of multiple providers. To this end the research aims to present the architecture, agent functionality and interactions of the CARMA system, as well as the structure of the marketplace, contract specification and risk management. As the scope and concepts of the proposed system are relatively unexplored, a model and simulation were developed to verify the concepts, explore the issues, assess the assumptions and validate the system. The results of the simulation determined that the introduction of CARMA has the potential to reduce the risk in contracting new services, increase the reliability of contracted services, and increase the utility of providers participating in the market

Environmental Entitlements: An Outline Framework for Analysis, and a Mongolian Case Study

The uses and management o f renewable natural resources (RNRs), and their consequences fo r sustainability, are mediated in intended and unintended ways by institutional arrangements. This paper highlights some pitfalls in the existing literature on povertyenvironment linkages in developing countries, and offers an alternative analytical approach based on the notion o f 'environmental entitlements'. This more socially articulated approach examines the determinants o f effective legitimate command over RNRs, including the rules and institutions that control access, according to the distinctive positions o f particular groups o f people. The approach is illustrated with reference to the case o f pastoral ecosystems under economic transition in Mongolia, and specifically to the community-based management o f common grazing land. Three key themes are drawn out, which are of relevance fo r the management o f RNRs in other developing economies undergoing structural reform: (a) the problem o f 'institutional scarcity’ in the face o f new transaction costs; (b) the distinction between the roles o f governance and government in RNR management; and (c) the importance of locally evolved, community-based institutions in managing environments at disequilibrium. Key words : — entitlements analysis — institutions — environment and poverty — marginal environments — political ecology — non-equilibrium ecology — governance — transitional economies — collective action — transaction cost

Contextual Factors in the Management of Common Grazing Lands: Lessons from Mongolia and Northwestern China

Seen in a global perspective, pastoral development is now increasingly motivated by social and environmental objectives rather than by production- or output-orientated objectives. Attention is shifting towards a broader concern with sustainability, both of grasslands, and of the livelihoods of those who rely on them (de Haan et al, 1997, Fratkin and Mearns forthcoming). Quite how these twin sustainability objectives may be achieved in particular contexts, however, is an empirical question. Drawing on examples from a diverse range of natural grassland-based livestock production systems under economic transition in Mongolia and northwestern China, this summary paper aims to show how an appreciation of context is essential if we are to understand how best to intervene in common grazing systems in order to achieve secure and sustainable livelihoods for livestock producers while at the same time promoting sustainable grassland management