783 research outputs found
The Two-Point Function and the Effective Magnetic Field in Diluted Ising Models on the Cayley Tree
Some results on the two-point function and on the analytic structure of the
momenta of the effective fugacity at the origin for a class of diluted
ferromagnetic Ising models on the Cayley tree are presented.Comment: 22 page
Technological innovation in banking services: an exploratory analysis to perceptions of the front office employee
It is widely recognized that the increased intensity of competition in the banking sector has had direct implications for financial institutions' approach to customers and how they define their business strategy. Considering that the current economic stance embraces innovation and technology as fundamental elements of strategic management and business and economic development, new approaches to the relationship between technological innovation and financial services are essential in achieving competitive advantage. Based on this premise, the purpose of this paper is to analyze the main effects of technological innovation on financial services at the bank branch level by evaluating responses from front office employees. The results show that information and communication technologies are an important lever in the modernization of the sector. Practical implications, strengths and limitations of our empirical study are also presente
Aspects of Two-Level Systems under External Time Dependent Fields
The dynamics of two-level systems in time-dependent backgrounds is under
consideration. We present some new exact solutions in special backgrounds
decaying in time. On the other hand, following ideas of Feynman, Vernon and
Hellwarth, we discuss in detail the possibility to reduce the quantum dynamics
to a classical Hamiltonian system. This, in particular, opens the possibility
to directly apply powerful methods of classical mechanics (e.g. KAM methods) to
study the quantum system. Following such an approach, we draw conclusions of
relevance for ``quantum chaos'' when the external background is periodic or
quasi-periodic in time.Comment: To appear in J. Phys. A. Mathematical and Genera
Saliency-based cooperative landing of a multirotor aerial vehicle on an autonomous surface vehicle
This paper presents a method for vision-based landing of a multirotor unmanned aerial vehicle (UAV) on an autonomous surface vehicle (ASV) equipped with a helipad. The method includes a mechanism for helipad behavioural search when outside the UAV’s field of view, a learning saliency-based mechanism for visual tracking the helipad, and a cooperative strategy for the final vision-based landing phase. Learning how to track the helipad from above occurs during takeoff and cooperation results from having the ASV tracking the UAV for assisting its landing. A set of experimental results with both simulated and physical robots show the feasibility of the presented method.info:eu-repo/semantics/acceptedVersio
Kelpie: A ROS-based multi-robot simulator for water surface and aerial vehicles
Testing and debugging real hardware is a time consuming task, in particular for the case of aquatic robots, for which it is necessary to transport and deploy the robots on the water. Performing waterborne and airborne field experiments with expensive hardware embedded in not yet fully functional prototypes is a highly risky endeavour. In this sense, physics-based 3D simulators are key for a fast paced and affordable development of such robotic systems. This paper contributes with a modular, open-source, and soon to be freely online available, ROS-based multi-robot simulator specially focused for aerial and water surface vehicles. This simulator is being developed as part of the RIVERWATCH experiment in the ECHORD european FP7 project. This experiment aims at demonstrating a multi-robot system for remote monitoring of riverine environments.info:eu-repo/semantics/acceptedVersio
Strong Coupling Theory of Two Level Atoms in Periodic Fields
We present a new convergent strong coupling expansion for two-level atoms in
external periodic fields, free of secular terms. As a first application, we
show that the coherent destruction of tunnelling is a third-order effect. We
also present an exact treatment of the high-frequency region, and compare it
with the theory of averaging. The qualitative frequency spectrum of the
transition probability amplitude contains an effective Rabi frequency.Comment: 4 pages with 3 figure
Online self-reconfigurable robot navigation in heterogeneous environments
This paper presents a robot navigation system capable of online self-reconfiguration according to the needs imposed by the various contexts present in heterogeneous environments. The ability to cope with heterogeneous environments is key for a robust deployment of service robots in truly demanding scenarios. In the proposed system, flexibility is present at the several layers composing the robot's navigation system. At the lowest layer, proper locomotion modes are selected according to the environment's local context. At the highest layer, proper motion and path planning strategies are selected according to the environment's global context. While local context is obtained directly from the robot's sensory input, global context is inspected from semantic labels registered off-line on geo-referenced maps. The proposed system leverages on the well-known Robotics Operating System (ROS) framework for the implementation of the major navigation system components. The system was successfully validated over approximately 1 Km long experiments on INTROBOT, an all-terrain industrial-grade robot equipped with four independently steered wheels.info:eu-repo/semantics/acceptedVersio
Acute Kidney Injury in the Context of Inflammatory Bowel Disease - A Clinical Case
Extraintestinal manifestations of inflammatory bowel disease are common and extendable to all organs. Kidney and lower genitourinary system occurs in 4-23% of cases. This may be dependent on inflammatory bowel disease activity, secondary to metabolic disorders, drugs or others. We present a case of a 68-year-old man with ulcerative colitis for 22 years admitted in our department for acute nephritic syndrome. Urinary microscopy suggested glomerular injury. A kidney biopsy was performed and was compatible with
acute interstitial nephritis and IgA nephropathy. Toxicity of mesalazine and glomerulonephritis secondary to ulcerative colitis were assumed. The patient suspended mesalazine and started prednisolone with clinical improvement. Our purpose is to sensitize the importance of having a prompt and thorough evaluation of acute kidney injury in patients with inflammatory bowel disease. We briefly review the broad spectrum of kidney manifestations in this population, focusing on mesalazine-induced nephrotoxicity.info:eu-repo/semantics/publishedVersio
Existence of the Bogoliubov S(g) operator for the quantum field theory
We prove the existence of the Bogoliubov S(g) operator for the
quantum field theory for coupling functions of compact support in space and
time. The construction is nonperturbative and relies on a theorem of
Kisy\'nski. It implies almost automatically the properties of unitarity and
causality for disjoint supports in the time variable.Comment: LaTeX, 24 pages, minor modifications, typos correcte
- …