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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.

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.

This paper studies the formation and management of an international entity for promoting the provision of global public goods in a setup of international treaties on concessions and reservations. Based on the so-called Vienna Convention by which there can be a discrepancy between the original treaty obligation and the ratified one in the multi-lateral treaty implementation, we construct two-stage mechanisms for international treaties on global public goods; the concession stage and the ratification stage with reservations. We explicitly analyze the optimal reservation levels from the optimal mechanism when the countries face asymmetric information on the preference parameters to global public goods. Specifically, we characterize the environments where the optimal mechanism with dominant-strategy incentive-compatibility and ex-post participation- constraint in the literature of mechanism design exists. The result shows that the sophisticatedly calculated transfers in the principal of quid pro quo control the international concessions and reservations.

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.

Social development is the ultimate goal of every nation, and climate change is a major stumbling block. Climate Risk Index has documented several climate change events with their devastations in terms of lives lost and economic cost. This study aims to link the climate change and renewable energy with the social progress of extreme climate affected countries.

This research used the top 50 most climate-affected countries of the decade and estimated the impact of climate risk on social progress with moderation effects of renewable energy and technology. Several competing panel data models such as quantile regression, bootstrap quantile regression and feasible generalized least square are used to generate robust estimates.

The results confirm that climate hazards obstruct socioeconomic progress, but renewable energy and technology can help to mitigate the repercussion. Moreover, improved institutions enhance the social progress of nations.

Government should improve the institutional quality that enhances their performance in terms of Voice and Accountability, Political Stability and Absence of Violence, Government Effectiveness, Regulatory Quality, Rule of Law and Control of Corruption to increase social progress. In addition, society should use renewable energy instead of fossil fuels to avoid environmental degradation and health hazards. Innovation and technology also play an important role in social progress and living standards, so there should be free hand to private business research and development, encouraging research institutes and universities to come forward for innovation and research.

The ultimate goal of all human struggle is to have progress that facilitates human beings to uplift their living standard. One of the best measures that can tell us about a nation’s progress is Social Progress Index (SPI), and one of many factors that can abruptly change it is the climate; so this study is an attempt to link the relationship among these variables and also discuss the situation where the impact of climate can be reduced.

Although social progress is an important concept of today’s economics discussion, relatively few studies are using the SPI to measure social well-being. Similarly, there is consensus about the impact of climate on people, government and crops but relatively less study about its overall impact on social progress, so this study attempts to fill the gap about the relationship between social progress and climate change.

The main contribution of this study is the solution for the impact of climate risk. Climate risk is not in human control, and we cannot eliminate it, but we can reduce the negative impacts of climate change. Moderator impact of renewable energy decreases the negative impact of climate change, so there is a need to use more renewable energy to mitigate the bad consequences of climate on social progress. Another moderator is technology; using technology will also mitigate the negative consequences of the climate, so there is a need to facilitate technological advancement.

This study aims to investigate the relationship between business group affiliation and CO2 emissions in Chile, providing insights into the pollution externalities associated with business group structures and their implications for environmental performance.

A hand-matched sample of industrial facilities and subsidiaries of listed firms in Chile was utilized to analyze the CO2 emissions of business group-affiliated firms compared to stand-alone firms. Fixed-effect regression analysis and propensity score matching were employed to examine the differences in emissions levels.

The results suggest that firms affiliated with business groups have higher CO2 emissions in comparison to similar stand-alone firms. This suggests that business group structures may weaken the pressures for emission reduction and maintenance of public legitimacy among affiliated firms.

The findings of this study are subject to certain limitations, such as the use of a specific dataset from Chile and the inability to explore certain factors due to data constraints. For instance, we were unable to examine the separation between control and cash-flow rights as well as the influence of manager characteristics on pollution levels. Future research should address these limitations and expand the analysis to other emerging market countries to further investigate the impact of lax or ineffective environmental regulations on pollution outcomes.

The research findings have practical implications for investors and policymakers. Investors interested in environmentally sustainable investments should consider the higher pollution levels associated with business group-affiliated firms. Policymakers can use these findings to design more effective regulations and incentives to encourage emission reduction efforts within business group structures.

The study’s results emphasize the need for a comprehensive understanding of the environmental implications of business group affiliation. By recognizing the potential for higher emissions in business group structures, stakeholders can advocate for sustainable practices, encourage transparency and promote responsible environmental management within corporate entities.

This study contributes to the literature on corporate governance, climate risks and pollution externalities by providing an empirical evidence on the relationship between business group affiliation and CO2 emissions. It highlights the importance of considering the influence of corporate structures on environmental performance, particularly in the context of emerging market economies.

Este estudio tiene como objetivo investigar la relación entre la afiliación a grupos empresariales y las emisiones de CO2 en Chile, proporcionando información sobre las externalidades de contaminación asociadas con las estructuras de grupos empresariales y sus implicaciones para el desempeño ambiental de las empresas.

Se utilizó una muestra recolectada de manera manual de instalaciones industriales y subsidiarias de empresas listadas en Chile para analizar las emisiones de CO2 de empresas afiliadas a grupos empresariales en comparación con empresas independientes. Se emplearon análisis de regresión de efectos fijos y modelos de emparejamiento por puntaje de propensión para examinar las diferencias en los niveles de emisiones.

Los resultados sugieren que las empresas afiliadas a grupos empresariales tienen mayores emisiones de CO2 en comparación con empresas independientes similares. Esto sugiere que las estructuras de grupos empresariales pueden debilitar las presiones para la reducción de emisiones y el mantenimiento de la legitimidad pública entre las empresas afiliadas.

Este estudio contribuye a la literatura sobre gobierno corporativo, riesgos climáticos y externalidades de contaminación al proporcionar evidencia empírica sobre la relación entre la afiliación a grupos empresariales y las emisiones de CO2. Destaca la importancia de considerar la influencia de las estructuras corporativas en el rendimiento ambiental, especialmente en el contexto de las economías de mercados emergentes.

Los hallazgos de este estudio están sujetos a ciertas limitaciones, como el uso de un conjunto de datos específico de Chile y la incapacidad para explorar ciertos factores debido a restricciones de datos. Por ejemplo, no pudimos examinar la influencia de las características de los ejecutivos de las empresas en los niveles de contaminación. Investigaciones futuras deberían abordar estas limitaciones y ampliar el análisis a otros países de mercados emergentes para investigar más a fondo el impacto de regulaciones ambientales laxas o ineficaces en los resultados de contaminación.

Los hallazgos de la investigación tienen implicaciones prácticas para inversores y responsables políticos. Los inversores interesados en inversiones ambientalmente sostenibles deben tener en cuenta los niveles más altos de contaminación asociados con empresas afiliadas a grupos empresariales. Los responsables políticos pueden utilizar estos hallazgos para diseñar regulaciones más efectivas e incentivos para fomentar los esfuerzos de reducción de emisiones dentro de las estructuras de grupos empresariales.

Los resultados del estudio enfatizan la necesidad de comprender de manera integral las implicaciones ambientales de la afiliación a grupos empresariales. Al reconocer el potencial de mayores emisiones en las estructuras de grupos empresariales, los interesados pueden abogar por prácticas sostenibles, fomentar la transparencia y promover una gestión ambiental responsable dentro de las entidades corporativas.

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 research integrates maintenance planning and production scheduling from a green perspective to reduce the carbon footprint.

A mixed-integer nonlinear programming (MINLP) model is developed to study the relation between production makespan, energy consumption, maintenance actions and footprint, i.e. service level and sustainability measures. The speed scaling technique is used to control energy consumption, the capping policy is used to control CO2 footprint and preventive maintenance (PM) is used to keep the machine working in healthy conditions.

It was found that ignoring maintenance activities increases the schedule makespan by more than 21.80%, the total maintenance time required to keep the machine healthy by up to 75.33% and the CO2 footprint by 15%.

The proposed optimization model can simultaneously be used for maintenance planning, job scheduling and footprint minimization. Furthermore, it can be extended to consider other maintenance activities and production configurations, e.g. flow shop or job shop scheduling.

Maintenance planning, production scheduling and greenhouse gas (GHG) emissions are intertwined in the industry. The proposed model enhances the performance of the maintenance and production systems. Furthermore, it shows the value of conducting maintenance activities on the machine's availability and CO2 footprint.

This work contributes to the literature by combining maintenance planning, single-machine scheduling and environmental aspects in an integrated MINLP model. In addition, the model considers several practical features, such as machine-aging rate, speed scaling technique to control emissions, minimal repair (MR) and PM.

In today’s fashion world, technology has taken on an important role for the creation of novel design effects. As a type of digital technology, laser engraving is applied for decorative purposes with unique fashion design looks. With this technology, simple and complex patterns can be engraved onto the surface of garments by using laser beam scanning. This study explores the application of laser technology on assembled garments for diverse engraved patterns. To improve the visual appearance, different design methods, such as the graphic and resist methods, are applied for carbon dioxide (CO2) laser engraving onto garments made from rayon/polyester blended fabric with optimal laser engraving parameters, including resolution (dpi) and pixel time (μs). This study also reveals the many potential of fashion designs through the use of laser engraving technology. Based on computer-aided design, laser engraving could open up new possibilities for green fashion design with distinct patterns and textures that would cater to the demands of industries and consumers.

The aim of this study is to assess the opportunity for the development of hydrocarbon transportation using high-strength steel (HSS) in pipeline construction in terms of cost savings and reliability.

Several optimizations of pipeline design and operations were performed to estimate the total life-cycle cost variation associated with different grades of high-strength steel. The generalized reduced gradient (GRG) method was used in an Excel table to determine optimal total life cycle each pipeline. Variables used in this optimization with respect to each steel grade were as follows: pipeline external diameter, wall thickness, number of compression stations and installed power in each compression station. The reliability of a pipeline with optimal cost was assessed to highlight the impact of steel grade on pipeline reliability.

The study showed that the cost reduction is strongly dependent on the adopted gas pipeline configuration. The number of compression stations and external diameter are the main factors influencing the pipeline total life cycle cost, while the steel price seems to have a minor effect, the reduction of the gas pipeline total life cycle does not exceed 5% even with a 50% difference in pipe steel prices between X70 and X100 steels. On the other side, for the same external diameter, X100 steel presents better pipeline reliability against carbonic corrosion compared to X70 steel.

The main contribution of this study is to provide a decision-support tool to help pipeline constructors enhance the profitability of natural gas transmission pipelines. The optimization method used is simple to use for design engineers during a feasibility study.

The present study presents one step to fill the gap concerning the question of balancing the trade-off between cost savings and structural reliability in high-strength steel pipelines during the early stages of feasibility studies. The optimal design and operations parameters ensuring cost savings on total life cycle costs are identified via an optimization method. The impact of selected optimal parameters on the long-term pipeline service life was estimated via a structural reliability analysis.