Dipolar gases in quasi one-dimensional geometries

We analyze the physics of cold dipolar gases in quasi one-dimensional geometries, showing that the confinement-induced scattering resonances produced by the transversal trapping are crucially affected by the dipole-dipole interaction. As a consequence, the dipolar interaction may drastically change the properties of quasi-1D dipolar condensates, even for situations in which the dipolar interaction would be completely overwhelmed by the short-range interactions in a 3D environment.Comment: 4 pages, 3 eps figure

Modular networks emerge from multiconstraint optimization

Modular structure is ubiquitous among complex networks. We note that most such systems are subject to multiple structural and functional constraints, e.g., minimizing the average path length and the total number of links, while maximizing robustness against perturbations in node activity. We show that the optimal networks satisfying these three constraints are characterized by the existence of multiple subnetworks (modules) sparsely connected to each other. In addition, these modules have distinct hubs, resulting in an overall heterogeneous degree distribution.Comment: 5 pages, 4 figures; Published versio

A progressive study into offshore wind farm maintenance optimisation using risk based failure analysis.

Offshore Wind Farm consists of an array of Wind Turbines electrical, communication, command and control systems. At present the cost of maintaining Wind Turbines in the offshore locations is very high (about 35% of lifetime costs). This work puts emphasis on using failure analysis as a basis for designing a condition based prognostic maintenance plan in order to control cost of power and make maintenance more efficient. An essential aspect of such failure analysis is to identify wind turbine components, ascertain their failures and find root causes of the failures. However as a first step, identification of prominent failures in the critical assemblies of a wind turbine using available inspection methods and making provisions to control their occurrence would make significant contribution in improving wind turbine reliability. This work introduces Failure Modes Effects and Criticality Analysis (FMECA) as an important failure analysis tool that has in the past successfully benefitted the airlines, marine, nuclear and spacecraft industries. FMECA is a structured failure analysis technique that can also evaluate the risk and priority number of a failure and hence assist in prioritising maintenance works. The work shows, how with a slight modification of the existing FMECA method, a very useful failure analysis method can be developed for offshore wind turbines including its operational uniqueness. This work further proposes modifying the format for calculating the Risk Priority Number (RPN) for wind turbine failure. By using wind turbine gearbox as a case study, this work illustrates the usefulness of RPN number in identifying failures which can assist in designing cost effective maintenance plan. Some preliminary results of a FMECA tool that has been developed to automatically evaluate the effects and criticality of a failure in a wind turbine at the component level is included

Friction and diffusion of matter-wave bright solitons

We consider the motion of a matter-wave bright soliton under the influence of a cloud of thermal particles. In the ideal one-dimensional system, the scattering process of the quasiparticles with the soliton is reflectionless, however, the quasiparticles acquire a phase shift. In the realistic system of a Bose-Einstein condensate confined in a tight waveguide trap, the transverse degrees of freedom generate an extra but small nonlinearity in the system which gives rise to finite reflection and leads to dissipative motion of the soliton. We calculate the velocity and temperature-dependent frictional force and diffusion coefficient of a matter wave bright soliton immersed in a thermal cloud

Scalable Microfabrication Procedures for Adhesive-Integrated Flexible and Stretchable Electronic Sensors.

New classes of ultrathin flexible and stretchable devices have changed the way modern electronics are designed to interact with their target systems. Though more and more novel technologies surface and steer the way we think about future electronics, there exists an unmet need in regards to optimizing the fabrication procedures for these devices so that large-scale industrial translation is realistic. This article presents an unconventional approach for facile microfabrication and processing of adhesive-peeled (AP) flexible sensors. By assembling AP sensors on a weakly-adhering substrate in an inverted fashion, we demonstrate a procedure with 50% reduced end-to-end processing time that achieves greater levels of fabrication yield. The methodology is used to demonstrate the fabrication of electrical and mechanical flexible and stretchable AP sensors that are peeled-off their carrier substrates by consumer adhesives. In using this approach, we outline the manner by which adhesion is maintained and buckling is reduced for gold film processing on polydimethylsiloxane substrates. In addition, we demonstrate the compatibility of our methodology with large-scale post-processing using a roll-to-roll approach

Study of maternal and perinatal outcome in women with congenital heart disease

Background: Pregnancy induced changes in cardiovascular hemodynamics are generally well tolerated. However, the reversible but prolonged hemodynamic stress of pregnancy can have negative effects on the diseased heart. In our study we studied various uncorrected and corrected congenital cardiac lesions and their antenatal, intrapartum course, their ability to withstand labor and postpartum complications. Methods: Our study was a retroprospective observational cross-sectional study conducted at KEM hospital, Mumbai with enrolment of total 27 subjects over a period of 18 months between August 2020 to December 2021.The study included all the registered and emergency patients either post abortal or post-delivery with congenital cardiac diseases including the ones who were surgically corrected. Results: The present study was conducted to study demographic features and maternal and perinatal outcomes of pregnancy in these women. Majority of the subjects were diagnosed with heart disease at the age more than 20 years (40.74%) and very few at age less than 5 years. In the present study only 7.4% study subjects were aware about pre-marital counselling, and preconceptional counselling. Among the lesions ASD was commonest reported among 51.85% study subjects. ICU admission was required among 11.11% study subjects. Labour analgesia given to only 18.52% study subjects. We did not observe any association between surgically corrected CHD and ICU admissions, postnatal complications, and outcomes, p>0.05. Conclusions: This study concluded that pre-pregnancy diagnosis, counselling, appropriate referral, routine antenatal supervision and delivery at an equipped centre improve the overall outcomes

Coupling of Transport and Chemical Processes in Catalytic Combustion

Catalytic combustors have demonstrated the ability to operate efficiently over a much wider range of fuel air ratios than are imposed by the flammability limits of conventional combustors. Extensive commercial use however needs the following: (1) the design of a catalyst with low ignition temperature and high temperature stability, (2) reducing fatigue due to thermal stresses during transient operation, and (3) the development of mathematical models that can be used as design optimization tools to isolate promising operating ranges for the numerous operating parameters. The current program of research involves the development of a two dimensional transient catalytic combustion model and the development of a new catalyst with low temperature light-off and high temperature stablity characteristics

Chimera order in spin systems

Homogeneous populations of oscillators have recently been shown to exhibit stable coexistence of coherent and incoherent regions. Generalizing the concept of chimera states to the context of order-disorder transition in systems at thermal equilibrium, we show analytically that such complex ordering can appear in a system of Ising spins, possibly the simplest physical system exhibiting this phenomenon. We also show numerically the existence of chimera ordering in 3-dimensional spin systems that model layered magnetic materials, suggesting possible means of experimentally observing such states.Comment: 5 pages, 3 figure

Asset Choice And Time Diversification Benefits

The issue of time diversification has been controversial. While some findings support time diversification, others do not. For example, Hodges, Taylor and Yoder (1997) find bonds outperform stocks, but Mukherji (2002) finds stocks provide time diversification benefits. This paper investigates whether the differences in the findings of Hodges, Taylor and Yoder (1997) and Mukherji (2002) stem from methodological variation. Results indicate that the differences in the procedure used to estimate the holding period returns may in fact be the reason for the difference in findings. Using a procedure to estimate holding period returns that is similar to Hodges, Taylor and Yoder (1997), and a performance measure that is similar to Mukherji (2002), we do not find that stocks provide time diversification benefits