19 resultados para dS vacua in string theory
Resumo:
Recent calls in the corporate social reporting (CSRep) literature have emphasized the importance of giving voice to non-managerial stakeholder groups in the social reporting process. The research, presented in this paper, employs recent work in stakeholder theory and CSRep to examine the perceptions of a diverse set of non-managerial stakeholders in the context of a developing country, Bangladesh. A series of semi-structured interviews were conducted with individuals who identify with various non-managerial stakeholder groups. Interviewees generally believed that the motivation and practice of CSRep in Bangladesh is developing in response to pressures from international markets and is producing largely cosmetic responses. Also, they expressed concerns that, given the economic, political, and social conditions in Bangladesh, premature adoption of strict CSRep standards may lead to increased corruption and other unintended consequences. Whilst some of the interviewees sharply criticized the current process of imposing social accounting codes/standards on developing countries which fail to consider the important local socio-economic context, the findings suggest that there is overwhelming support for mandatory externally verified CSRep based on the principles of peoples' right to know, full disclosure/completeness, and relevance, which are anchored in the broader principles of transparency and stakeholder accountability. © 2010 Springer Science+Business Media B.V.
Resumo:
Over the last twenty years, we have been continuously seeing R&D efforts and activities in developing optical fibre grating devices and technologies and exploring their applications for telecommunications, optical signal processing and smart sensing, and recently for medical care and biophotonics. In addition, we have also witnessed successful commercialisation of these R&Ds, especially in the area of fibre Bragg grating (FBG) based distributed sensor network systems and technologies for engineering structure monitoring in industrial sectors such as oil, energy and civil engineering. Despite countless published reports and papers and commercial realisation, we are still seeing significant and novel research activities in this area. This invited paper will give an overview on recent advances in fibre grating devices and their sensing applications with a focus on novel fibre gratings and their functions and grating structures in speciality fibres. The most recent developments in (i) femtosecond inscription for microfluidic/grating devices, (2) tilted grating based novel polarisation devices and (3) dual-peak long-period grating based DNA hybridisation sensors will be discussed.
Resumo:
Optical fiber materials exhibit a nonlinear response to strong electric fields, such as those of optical signals confined within the small fiber core. Fiber nonlinearity is an essential component in the design of the next generation of advanced optical communication systems, but its use is often avoided by engineers because of its intractability. The application of nonlinear technologies in fiber optics offers new opportunities for the design of photonic systems and devices. In this chapter, we make an overview of recent progress in mathematical theory and practical applications of temporal dissipative solitons and self-similar nonlinear structures in optical fiber systems. The design of all-optical high-speed signal processing devices, based on nonlinear dissipative structures, is discussed.
Resumo:
We overview our recent developments in the theory of dispersion-managed (DM) solitons within the context of optical applications. First, we present a class of localized solutions with a period multiple to that of the standard DM soliton in the nonlinear Schrödinger equation with periodic variations of the dispersion. In the framework of a reduced ordinary differential equation-based model, we discuss the key features of these structures, such as a smaller energy compared to traditional DM solitons with the same temporal width. Next, we present new results on dissipative DM solitons, which occur in the context of mode-locked lasers. By means of numerical simulations and a reduced variational model of the complex Ginzburg-Landau equation, we analyze the influence of the different dissipative processes that take place in a laser.