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Purpose – This chapter outlines the need for policy packages in urban areas, demonstrates how effective policy packages can be designed by combining appropriate policy…
Purpose – This chapter outlines the need for policy packages in urban areas, demonstrates how effective policy packages can be designed by combining appropriate policy instruments and discusses the implications for Chinese cities.
Methodology – The results in the chapter are derived from a predictive model of two UK cities (Edinburgh and Leeds), an objective function to reflect a city's objectives and constraints, and an optimising routine which identifies the most effective level of intervention for each policy instrument.
Findings – Where available, fuel taxes, fare levels, road pricing charges, low-cost capacity improvements and public transport frequencies are the most effective policy instruments. Optimal combinations designed to cost no more than current strategies offer substantial benefits to society. Infrastructure projects typically offer much lower value for money. Strategies designed to meet challenging climate change targets can be designed, but may well substantially reduce other benefits.
Research limitations/implications – Other policy instruments such as awareness campaigns and walking and cycling measures could be tested in a similar way. Similar analyses could be conducted in high growth contexts typical of Chinese cities.
Practical and social implications – Policy packages will be important for Chinese cities. They are likely to differ from European specifications, and include greater use of infrastructure. The methodology presented here could be applied to their design.
Originality – The chapter brings together research reported elsewhere, presents some new results on synergy and discusses the implications for China.
The purpose of this research paper is to optimize the process parameters of selective laser sintering process, and the sintered parts of PA2200 prototypes are built with…
The purpose of this research paper is to optimize the process parameters of selective laser sintering process, and the sintered parts of PA2200 prototypes are built with minimum surface roughness within the range of 10-12 microns using the Taguchi design of experiments approach.
In this research paper, a 3D model is created using catia V5 and exported to rapid prototype machine, and the 3D model file was repaired by using Magics software to remove the facets and saved with file extension .stl (standard triangulation language).Taguchi design of experiments approach L9 orthogonal array was selected with three factors at three levels each and total nine experiments were conducted with the quality index lower-the-better signal-to-noise ratio to produced better quality prototypes by optimizing the process parameters like laser power, layer thickness and temperature and tested on surface tester for surface roughness. The experimental results of surface roughness were compared with Regression Analysis, S/N Ratio, Analysis of Mean and predicted model on sintered prototypes.
The experimental results obtained after testing on the surface tester compared with mathematical model for the quality index lower-the-better signal-noise ratio with optimal process parameters operating at Temperature at level 3, Layer thickness at level 3, and Laser power at level 3, regression analysis, and predictive model the output response variable surface roughness, is with in the range of 9-10.5 microns are all most same and from ANOM (Analysis of Mean), temperature at leve1, layer thickness at level 2, laser power at level 2 is 9 -9.6 microns.
The process parameters such as beam diameter and table speed were not considered on output response variable surface roughness in this research paper.
All the experiments were conducted and the parts are produced by using the material PA2200 in the powder from and sintered by Co2 laser by varying the process parameters with optimal settings to produce minimum surface roughness the out put from this paper is the influence of process parameters on surface roughness can be predicted at optimal settings with in less time and cost.
Anyone who follows climate change policy debates even casually knows that these debates are shot through with controversy about what ought to be done and who ought to be…
Anyone who follows climate change policy debates even casually knows that these debates are shot through with controversy about what ought to be done and who ought to be doing it. What sometimes get lost in these debates, however, are much deeper differences over the nature of the climate change problem itself. That is my focus in this chapter. I will take climate change as a prime example of broader debates over what constitutes “sustainable development” and draw upon different strands of the sustainability literature to show how these disagreements play out in the climate change context.
One of the principal tools in analyzing climate change control policies is integrated assessment modeling. While indispensable for asking logical “what if” questions, such…
One of the principal tools in analyzing climate change control policies is integrated assessment modeling. While indispensable for asking logical “what if” questions, such as the cost-effectiveness of alternative policies or the economic efficiency of carbon taxes versus R&D subsidies, integrated assessment models (IAMs) can only produce “answers” that are as good as their underlying assumptions and structural fidelity to a very complex multi-component system. However, due to the complexity of the models, the assumptions underlying the models are often obscured. It is especially important to identify how IAMs treat uncertainty and the value-laden assumptions underlying the analysis.In particular, IAMs have difficulty adequately addressing the issue of uncertainty inherent to the study of climate change, its impacts, and appropriate policy responses. In this chapter, we discuss how uncertainty about climate damages influences the conclusions from IAMs and the policy implications. Specifically, estimating climate damages using information from extreme events, contemporary spatial climate analogs and subjective probability assessments, transients, “imaginable” surprises, adaptation, market distortions and technological change are given as examples of problematic areas that IA modelers need to explicitly address and make transparent of IAMs are to enlighten more than they conceal.
A construction project traditionally involves a variety of participants. Owners, consultants, and contractors all have diverse opinions and interests, but they all seek to…
A construction project traditionally involves a variety of participants. Owners, consultants, and contractors all have diverse opinions and interests, but they all seek to ensure project success. Success is habitually measured as performance output regarding cost, time, and quality. Despite previous research mapping the success and failure factors, construction managers seem to have difficulty in attaining success. To provide clearer guidance on how to fulfill success criteria, the purpose of this paper is to identify the underlying factors that affect performance and thus project success in construction processes.
A questionnaire survey based on a literature review provided 25 key process factors divided into five key categories. Based on the responses from commonly involved construction parties, the factors were ranked and tested for significant differences between the parties.
The top five most important process factors were found to relate to the sharing of knowledge and communication. Moreover, testing the ranking for significant differences between owners, consultants, and contractors revealed five differences. The differences related to the interpretation and importance of trust, shared objectives, project coordination, and alternative forms of coordination.
All respondents identify improved knowledge sharing and communication as the key to improved cost, time, and quality performance and are therefore the areas where construction managers need to focus their resources. Thus, improved experience sharing and communication will increase the likelihood of project success, through improving competences, commitment, and coordination.
Purpose – The purpose of this chapter is to propose a cross-assessment model as an analytical tool for developing sustainable urban transport and land-use strategies for a…
Purpose – The purpose of this chapter is to propose a cross-assessment model as an analytical tool for developing sustainable urban transport and land-use strategies for a low-carbon society.
Methodology – A cross-assessment model is developed based on demand and supply models of transport services. The model is able to generate a set of the optimal service levels in public transport reflecting selected target strategies. It is applied to an impact analysis of public transport and land-use strategies in 2030 for all of Japan's 269 urban areas,with outcomes – including the financial balance of public transport operation, user benefits and CO2 emissions reduction – compared among strategies and urban areas.
Findings – The analytical results show that three value factors of efficiency, equity and the environment do not necessarily conflict with each other. In particular, it is clarified that CO2-emission reduction targets can contribute to the improvement of both financial balance and user benefits at the national level. In addition, the results of comparative analysis among the land-use and transport integration (LUTI) scenarios demonstrate that a combination of urban transport strategies and land-use control in the form of ‘corridors and multi-centres’ provides greater emission reduction and increased user benefits.
Implications – The cross-assessment model developed in this chapter could serve as an analytical tool for strategic transport planning. The results in this chapter underlinethe benefit of LUTI strategies particularly in China.
Under the Kyoto Protocol Ireland is committed to ensuring that its greenhouse gas emission levels are at or below 113 per cent of 1990 levels for the years 2008–2012…
Under the Kyoto Protocol Ireland is committed to ensuring that its greenhouse gas emission levels are at or below 113 per cent of 1990 levels for the years 2008–2012. Irish emissions have already exceeded this limit by approximately 10 to 15 per cent and must be reduced if the Kyoto Protocol targets are to be met. In this context, and drawing on relevant theory and research, this paper discusses the rationale for, and the potential impact of, government intervention in the market for carbon dioxide (CO2) emissions. The use of a Carbon Tax as a policy tool in reducing CO2 emissions is examined from both economic and taxation perspectives. Particular attention is paid to the Irish National Climate Change Strategy formulated in 2000 and the consultation process on implementing a Carbon Tax initiated by the Department of Finance in 2003. In September 2004 the Irish Government decided not to implement the proposed Carbon Tax. Submissions from interested parties on the carbon tax consultation process are reviewed against the rationale for implementation of such a tax. The body of evidence presented in this paper supports the implementation of a Carbon Tax—suggesting that the decision not to implement such a tax may have been a lost opportunity. The paper argues that a well‐designed Carbon Tax for Ireland, a simple levy on a close proxy for emissions, would be effective in influencing taxpayer behaviour bringing about a reduction in Ireland's CO2 emissions and supporting the polluter pays principle. In the absence of a carbon tax Ireland's Kyoto target is unlikely to be met and the consequent financial penalties will fall on all taxpayers. The paper concludes that the Irish Government should revisit this decision.
As microelectronics continue to shrink, it is becoming increasingly difficult and expensive to mechanically drill very small via holes (<0·010 in.). Using lasers and…
As microelectronics continue to shrink, it is becoming increasingly difficult and expensive to mechanically drill very small via holes (<0·010 in.). Using lasers and optical technology, it is possible to drill any material. Thin circuit board materials of various compositions were investigated as candidates for laser drilling using a 100 watt CO2 laser. Laser variables were pulse frequency, duty cycle, and number of pulses (total energy delivered). Delivered energy seems to be the most critical parameter, and the optimal holes were drilled within a narrow energy band, although there was much data scatter. The best laser drilled holes were of lower quality than that obtainable with mechanical drilling. Photographs of the best holes in all materials are included.
This chapter develops and examines a model of the relationship between consumption and environmental degradation, using per capita gross domestic product (GDP) as the…
This chapter develops and examines a model of the relationship between consumption and environmental degradation, using per capita gross domestic product (GDP) as the proxy for consumer behavior and per capita carbon dioxide emissions as the indicator of pollution. The time paths of emissions and consumption are modeled within a dynamic framework representative of ever-changing global economic and social conditions, and the result is expressed as an optimization problem from which Hamiltonian conditions are derived. Optimal control theory can be used to solve problems in dynamic economic analysis, and the Hamiltonian approach is one way of solving this class of problems. These conditions are analyzed through the use of a phase diagram, and the empirical section of the chapter reveals the relationship between CO2 emissions and GDP values for the aggregate of 148 nation states studied by the United Nations, as well as for developed, developing, and underdeveloped countries as classified by the United Nations. The results of our analysis are not encouraging unless significant changes are made to the policies of leading nations, and the chapter closes with a discussion of alternative policy paths that may ease the identified trends in environmental degradation.