750 research outputs found

    Two Dimensional Quantum Dilaton Gravity and the Positivity of Energy

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    Using an argument due to Regge and Teitelboim, an expression for the ADM mass of 2d quantum dilaton gravity is obtained. By evaluating this expression we establish that the quantum theories which can be written as a Liouville-like theory, have a lower bound to energy, provided there is no critical boundary. This fact is then reconciled with the observation made earlier that the Hawking radiation does not appear to stop. The physical picture that emerges is that of a black hole in a bath of quantum radiation. We also evaluate the ADM mass for the models with RST boundary conditions and find that negative values are allowed. The Bondi mass of these models goes to zero for large retarded times, but becomes negative at intermediate times in a manner that is consistent with the thunderpop of RST.Comment: 16 pages, phyzzx, COLO-HEP-309. (Confusing points in previous version clarified, discussion of ADM and Bondi masses in RST case added.

    Brane Worlds, the Cosmological Constant and String Theory

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    We argue that traditional methods of compactification of string theory make it very difficult to understand how the cosmological constant becomes zero. String inspired models can give zero cosmological constant after fine tuning but since string theory has no free parameters it is not clear that this is allowed. Brane world scenarios on the other hand while they do not answer the question as to why the cosmological constant is zero do actually allow a choice of integration constants that permit flat four space solutions. In this paper we discuss gauged supergravity realizations of such a world. To the extent that this starting point can be considered a low energy effective action of string theory (and there is some recent evidence supporting this) our model may be considered a string theory realization of this scenario.Comment: 18 pages, 5 figures. Shorter version and a few new comments adde

    Incumbents Influence on Family Business Succession Process

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    Post succession performance of family owned businesses has become ineffective. The foremost purpose of this study was to evaluate the level of influence coming from incumbent related factors on business succession processes in various successor modes. The targeted population was selected were the successors. The criteria to select the population were the family owned businesses that contain between 50 and 149 employees and who were involved in a business succession process within the last 10 years excluding the three years, 2007 to 2010. Sample was selected through simple random sampling method and consists of 128 units. The main data collection modes were a structured research questionnaire mail-out and data analysis was done mainly by using SPSS. All incumbents’ related factors have a positive relationship to initial satisfaction with the business succession process. However, the relatively important factors to generate higher levels of initial satisfaction with the business succession process is the relationship between incumbent and successor. The relative importance of influential factors changes when the succession mode changes. When succession is conducted with a family member successor, the most important factor for success is   successor’s relationship with the incumbent. However, when succession is done with an unrelated manager successor, there is no restively important factors to the business succession process The factors of relative importance to maximize business performance after the business succession process is: t the relationship between the incumbent and successor Keywords: Business Succession, Family Business, Incumben

    The Changing Landscape of Women’s Rights Activism in China: The Continued Legacy of the Beijing Conference

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    The Beijing Conference was a watershed moment in the history of the global women’s movement and had an unprecedented impact in the Global North and South on lawmaking, institution building, and movement building. This Article details the development of women’s activism in China since the Beijing Conference and how a changing legal landscape impacts this activism. While its progress is emblematic of the inconsistencies in the progression of women’s rights activism since the Beijing Conference, China’s efforts have been significant and varied and represent a model for other countries seeking to reform women’s rights legislation. This Article identifies important lines of inquiry that merit further investigation in China and offers insights for conducting similar investigations elsewhere. This Article also outlines a framework for the shifting nature of women’s legal activism from 1995 to 2020 and the ways that the international community can capitalize on these changes and continue to galvanize efforts toward legislative and cultural reform. This Article concludes that the Beijing Conference’s goals may be actualized with financial backing and an apolitical and academic focus, and asserts that increased unity among activist groups is needed in China

    The Problem of Time and Quantum Black Holes

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    We discuss the derivation of the so-called semi-classical equations for both mini-superspace and dilaton gravity. We find that there is no systematic derivation of a semi-classical theory in which quantum mechanics is formulated in a space-time that is a solution of Einstein's equation, with the expectation value of the matter stress tensor on the right-hand side. The issues involved are related to the well-known problems associated with the interpretation of the Wheeler-deWitt equation in quantum gravity, including the problem of time. We explore the de Broglie-Bohm interpretation of quantum mechanics (and field theory) as a way of spontaneously breaking general covariance, and thereby giving meaning to the equations that many authors have been using to analyze black hole evaporation. We comment on the implications for the ``information loss" problem.Comment: 30 pages, COLO-HEP-33

    Recruitment Advertising: Changes Within The Last Four Decades In Sri Lanka

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    Recruitment is one of the most important functions of the Human Resource Management and the success of the function is depended on the attraction of most suitable candidates to the relevant vacancy. To attract applicants, the organizations can be used no of modes, however among those, most popular one is newspaper advertisements. However just publishing advertisement on newspaper does not bring expected results. To get maximum results, the advertisements should be prepared in an attractive way. Under this study, it was evaluated the changes happen with newspaper advertisements within last fourdecades to get understand how that advertisements has create attractively and to understand the trends of the current newspaper advertisements. For that, it has used 200 published advertisements with the period 1970 –2009 as a sample of the study. According to the results usage of graphics, company logo, pictures, have been increased. On the other hand, usage of descriptive language in recruitment advertisements has been increased. Most of recruitment advertisements presented the position in direct, however there is a trend to present in creative ways and with a statement that encourage applications

    Social media engagement and occupational stress

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    The study attempted to recognized the relationship between social media engagement and occupational stress of millennial employees in private sector, Sri Lanka. It was further evaluated whether the gender moderate the relationship between above two variables. Population of the study is millennial employees who are using Facebook for social media engagement in private sector organizations and used cluster and convenience sampling techniques to select sample units. The sample size of this study was 68 employees. This study mainly based on primary data which collect through a survey. According to survey, 26.47% of employees spend one to two hours for social media and 22.6% respondents used Social Media for update on friend’s activity. The study findings revealed that there is a significant moderate positive relationship between social media engagement and occupational stress. Further, it was indicated that relationship between social media engagement and occupational stress was not moderated by the gender. Hence, the study can be concluded that there is a moderate relationship between two factors and gender differences do not strengthen or weaker the relationship between social media engagement and occupational stress

    Enhanced change detection index for disaster response, recovery assessment and monitoring of buildings and critical facilities-A case study for Muzzaffarabad, Pakistan

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    The availability of Very High Resolution (VHR) optical sensors and a growing image archive that is frequently updated, allows the use of change detection in post-disaster recovery and monitoring for robust and rapid results. The proposed semi-automated GIS object-based method uses readily available pre-disaster GIS data and adds existing knowledge into the processing to enhance change detection. It also allows targeting specific types of changes pertaining to similar man-made objects such as buildings and critical facilities. The change detection method is based on pre/post normalized index, gradient of intensity, texture and edge similarity filters within the object and a set of training data. More emphasis is put on the building edges to capture the structural damage in quantifying change after disaster. Once the change is quantified, based on training data, the method can be used automatically to detect change in order to observe recovery over time in potentially large areas. Analysis over time can also contribute to obtaining a full picture of the recovery and development after disaster, thereby giving managers a better understanding of productive management and recovery practices. The recovery and monitoring can be analyzed using the index in zones extending from to epicentre of disaster or administrative boundaries over time.EU FP

    Enhanced change detection index for disaster response, recovery assessment and monitoring of accessibility and open spaces (camp sites)

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    The availability of Very High Resolution (VHR) optical sensors and a growing image archive that is frequently updated, allows the use of change detection in post-disaster recovery and monitoring for robust and rapid results. The proposed semi-automated GIS object-based method uses readily available pre-disaster GIS data and adds existing knowledge into the processing to enhance change detection. It also allows targeting specific types of changes pertaining to similar man-made objects. This change detection method is based on pre/post normalized index, gradient of intensity, texture and edge similarity filters within the object and a set of training data. Once the change is quantified, based on training data, the method can be used automatically to detect change in order to observe recovery over time in large areas. Analysis over time can also contribute to obtaining a full picture of the recovery and development after disaster, thereby giving managers a better understanding of productive management practices.EU FP

    Hamiltonian Approach to 2D Dilaton-Gravities and Invariant Adm Mass

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    The formula existing in the literature for the ADM mass of 2D dilaton gravity is incomplete. For example, in the case of an infalling matter shockwave this formula fails to give a time-independent mass, unless a very special coordinate system is chosen. We carefully carry out the canonical formulation of 2D dilaton gravity theories (classical, CGHS and RST). As in 4D general relativity one must add a boundary term to the bulk Hamiltonian to obtain a well-defined variational problem. This boundary term coincides with the numerical value of the Hamiltonian and gives the correct mass which obviously is time-independent.Comment: revised, 12 pages, PUPT-1379; we added a reference and corrected some minor typo
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