Optical nanofiber-based cavity induced by periodic air-nanohole arrays

We experimentally realized an optical nanofiber-based cavity by combining a 1-D photonic crystal and Bragg grating structures. The cavity morphology comprises a periodic, triplex air-cube introduced at the waist of the nanofiber. The cavity has been theoretically characterized using FDTD simulations to obtain the reflection and transmission spectra. We have also experimentally measured the transmission spectra and a Q-factor of ~784(87) for a very short periodic structure has been observed. The structure provides strong confinement of the cavity field and its potential for optical network integration makes it an ideal candidate for use in nanophotonic and quantum information systems

Chiral force of guided light on an atom

We calculate the force of a near-resonant guided light field of an ultrathin optical fiber on a two-level atom. We show that, if the atomic dipole rotates in the meridional plane, the magnitude of the force of the guided light depends on the field propagation direction. The chirality of the force arises as a consequence of the directional dependencies of the Rabi frequency of the guided driving field and the spontaneous emission from the atom. This provides a unique method for controlling atomic motion in the vicinity of an ultrathin fiber.Comment: text and figures were revised, and a new discussion was adde

Stochastic and deterministic models for age-structured populations with genetically variable traits

Understanding how stochastic and non-linear deterministic processes interact is a major challenge in population dynamics theory. After a short review, we introduce a stochastic individual-centered particle model to describe the evolution in continuous time of a population with (continuous) age and trait structures. The individuals reproduce asexually, age, interact and die. The 'trait' is an individual heritable property (d-dimensional vector) that may influence birth and death rates and interactions between individuals, and vary by mutation. In a large population limit, the random process converges to the solution of a Gurtin-McCamy type PDE. We show that the random model has a long time behavior that differs from its deterministic limit. However, the results on the limiting PDE and large deviation techniques \textit{\`a la} Freidlin-Wentzell provide estimates of the extinction time and a better understanding of the long time behavior of the stochastic process. This has applications to the theory of adaptive dynamics used in evolutionary biology. We present simulations for two biological problems involving life-history trait evolution when body size is plastic and individual growth is taken into account.Comment: This work is a proceeding of the CANUM 2008 conferenc

Business model assessment in faecal sludge management in selected Vietnamese cities

An assessment of business models in faecal sludge management (FSM) in 3 largest Vietnamese cities of Hanoi, Hai Phong, and Ho Chi Minh has been conducted through interview of 1,000 households and survey at 20 FS emptying operators. The public enterprises keep a significant market share for FSM. However, these enterprises run FSM business as a ‘‘must do” activity, which is subsidized by the city’s budget. In order to reduce operation costs and to make benefit, most of private enterprises are practicing illegal FS dumping. Financial status of private enterprises looks less optimistic in scenarios where FS is required to be brought to landfill or composting plant. A number of enterprises would not find capital recovery within 5 years, and some others would face loss. For sustainable FSM business, costs for adequate FSM should be recovered, while regulatory support and coordination role of local authorities are needed

Factors Influencing Online Booking Trial Decision in Ho Chi Minh City, Vietnam

Online booking has turned out to be increasingly prominent technique to offer travel items and is generally acknowledged in created nations. In spite of the fact that this idea has been presented in Vietnam for as long as couple of years, there are half of air tickets is sold online right now. There are different looks into directed concentrating on the elements affecting individuals aim to receive online booking. Be that as it may, there are relatively few explores concentrate on the aim to attempt online booking. This expectation to attempt is vital since individuals perfer to attempt initially, at that point they will assess their trial encounter, subsequently, embrace or reject web based booking innovation. In this manner, this exploration accentuates on discovering factors that impact individuals goal to attempt web based booking. The overview has been created in view of serious survey of literary works identified with web based booking, internet shopping, selection hypotheses, purchaser practices. The surveys have been conveyed and the information has been handled utilizing SEM-PLS to decide the connection between factors that impact Vietnamese expectation to attempt web based booking. Therefore, this exploration is required to have noteworthy commitment in both hypothesis and common sense. As far as hypothesis, this examination effectively proviced the model that exhibit the goal to attempt web based booking which is once in a while talked about in past explores. In term of common sense, this exploration gives a general bits of knowledge of Vietnamese online booker trademark for online travel organization working in Vietnam keeping in mind the end goal to enhance their business execution. Keywords: online booking trial, e-commerce trial, vietnam tourism industry, e-commerce, triability

Coexistence of generalized synchronization and inverse generalized synchronization between chaotic and hyperchaotic systems

In this paper, we present new schemes to synchronize different dimensional chaotic and hyperchaotic systems. Based on coexistence of generalized synchronization (GS) and inverse generalized synchronization (IGS), a new type of hybrid chaos synchronization is constructed. Using Lyapunov stability theory and stability theory of linear continuous-time systems, some sufficient conditions are derived to prove the coexistence of generalized synchronization and inverse generalized synchronization between 3D master chaotic system and 4D slave hyperchaotic system. Finally, two numerical examples are illustrated with the aim to show the effectiveness of the approaches developed herein