6,632 research outputs found

    Black hole quasinormal mode spectroscopy with LISA

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    The signal-to-noise ratio (SNR) for black hole quasinormal mode sources of low-frequency gravitational waves is estimated using a Monte Carlo approach that replaces the all-sky average approximation. We consider an eleven dimensional parameter space that includes both source and detector parameters. We find that in the black-hole mass range M4M\sim 4-7×106M7\times 10^6M_{\odot} the SNR is significantly higher than the SNR for the all-sky average case, as a result of the variation of the spin parameter of the sources. This increased SNR may translate to a higher event rate for the Laser Interferometer Space Antenna (LISA). We also study the directional dependence of the SNR, show at which directions in the sky LISA will have greater response, and identify the LISA blind spots.Comment: 12 pages, 5 figure

    Data Mining to Support Engineering Design Decision

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    The design and maintenance of an aero-engine generates a significant amount of documentation. When designing new engines, engineers must obtain knowledge gained from maintenance of existing engines to identify possible areas of concern. Firstly, this paper investigate the use of advanced business intelligence tenchniques to solve the problem of knowledge transfer from maintenance to design of aeroengines. Based on data availability and quality, various models were deployed. An association model was used to uncover hidden trends among parts involved in maintenance events. Classification techniques comprising of various algorithms was employed to determine severity of events. Causes of high severity events that lead to major financial loss was traced with the help of summarization techniques. Secondly this paper compares and evaluates the business intelligence approach to solve the problem of knowledge transfer with solutions available from the Semantic Web. The results obtained provide a compelling need to have data mining support on RDF/OWL-based warehoused data

    History, Violence and Collective Memory: Implications for Mental Health in Ecuador

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    National histories of violence shape experiences of suffering and professional responses. In Ecuador, mental health literature addressing this crucial issue is scarce and little debated. In contrast, local psychiatrists and psychologists within the country face contemporary challenges that are deeply rooted in a violent colonial past and the perpetuation of its fundamental ethos. This paper critically reviews relevant literature on collective memory and historical trauma, and focuses on Ecuador as a case study on how to incorporate history into modern mental health challenges. The discussion poses key questions and outlines possible ways for Ecuador to address the link between history and mental health, including insights from countries that have struggled with their violent pasts. This paper contributes to ongoing international debate on the role of cultural history in mental health with implications for social scientists and practising clinicians in former colonised nations

    A Study on Performance Appraisal at Future Lifestyle Fashion Ltd. (FLF) Mumbai

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    In this competitive world, business is playing a major role and performance appraisal (PA) has increasingly become part of strategic approach to integrating HR activities and business policies. Today we can see this standard term covering a variety of activities through which organizations seek to assess employees and develop their competence, improve performance and achieve rewards. The success of an organization depends on the performance of the employees and it is the human tendency. Appraising performance is both a difficult and an essential supervisory skill. Every organization judges formally or informally. If there are no fixed standards of judging they will start judging based on informal standards that can create lack of enthusiasm and impact the performance of the employee and in turn, the organization. Hence, it is essential that we set the right standards to judge the performance of the employees. At a strategic level, the need for speedy and effective organizational change in today's vibrant social, economic, and political environment requires that employees continually re align their performance with goals and objectives of the organization

    Lower cost automotive piston from 2124/SiC/25p metal-matrix composite

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    Engineered materials have made a breakthrough in a quest for materials with a combination of custom-made properties to suit particular applications. One of such materials is 2124/SiC/25p, a high-quality aerospace grade aluminium alloy reinforced with ultrafine particles of silicon carbide, manufactured by a powder metallurgy route. This aluminium matrix composite offers a combination of greater fatigue strength at elevated temperatures, lower thermal expansion and greater wear resistance in comparison with conventionally used piston materials. The microscale particulate reinforcement also offers good formability and machinability. Despite the benefits, the higher manufacturing cost often limits their usage in high-volume industries such as automotive where such materials could significantly improve the engine performance. This paper presents mechanical and forging data for a lower cost processing route for metal matrix composites. Finite element modelling and analysis were used to examine forging of an automotive piston and die wear. This showed that selection of the forging route is important to maximise die life. Mechanical testing of the forged material showed a minimal reduction in fatigue properties at the piston operating temperature

    Analysis of interconnection between Concurrent Engineering and Human Resource Management

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    In today\u27s global economy; the competition in market among various organizations has been increased by great extent. The success in market is depending upon innovative research in product design and development as well as its quick launching in market. Thus the main aim of the concept of Concurrent Engineering is to speed up the every process that occurs during production and reducing the new product launching time in the market. But at the same time the impact of human resource management on all the activities from hiring new employees to achieving the organizational goal can\u27t be neglected. The above mentioned activity of concurrent engineering is only possible if there is proper co-ordination and co-operation among various organizational departments and effective communication in employees. Also proper training to the employees for improving not only technical skills but also interpersonal skills of employees will lead towards successful achievement of an organizational goal. Hence Human Resource Management undividable interconnection with Concurrent Engineering if properly understood and studied. Thus, implementation of both concepts give rise to long term benefits to organization in terms of customer satisfaction and improved interest of shareholders as well as stakeholders. Using proper methodology it is easy to implement Human Resource Management based Concurrent Engineering to be a market leader in today\u27s cut- throat competition in this world

    Coordinated analysis of two graphite grains from the CO3.0 LAP 031117 meteorite: First identification of a CO Nova graphite and a presolar iron sulfide subgrain

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    Presolar grains constitute remnants of stars that existed before the formation of the solar system. In addition to providing direct information on the materials from which the solar system formed, these grains provide ground-truth information for models of stellar evolution and nucleosynthesis. Here we report the in-situ identification of two unique presolar graphite grains from the primitive meteorite LaPaz Icefield 031117. Based on these two graphite grains, we estimate a bulk presolar graphite abundance of 5-3+7 ppm in this meteorite. One of the grains (LAP-141) is characterized by an enrichment in 12C and depletions in 33,34S, and contains a small iron sulfide subgrain, representing the first unambiguous identification of presolar iron sulfide. The other grain (LAP-149) is extremely 13C-rich and 15N-poor, with one of the lowest 12C/13C ratios observed among presolar grains. Comparison of its isotopic compositions with new stellar nucleosynthesis and dust condensation models indicates an origin in the ejecta of a low-mass CO nova. Grain LAP-149 is the first putative nova grain that quantitatively best matches nova model predictions, providing the first strong evidence for graphite condensation in nova ejecta. Our discovery confirms that CO nova graphite and presolar iron sulfide contributed to the original building blocks of the solar system.Peer ReviewedPostprint (author's final draft
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