4,969 research outputs found
Formal verification of an autonomous personal robotic assistant
Humanârobot teams are likely to be used in a variety of situations wherever humans require the assistance of robotic systems. Obvious examples include healthcare and manufacturing, in which people need the assistance of machines to perform key tasks. It is essential for robots working in close proximity to people to be both safe and trustworthy. In this paper we examine formal verification of a high-level planner/scheduler for autonomous personal robotic assistants such as Care-O-bot ⢠. We describe how a model of Care-O-bot and its environment was developed using Brahms, a multiagent workflow language. Formal verification was then carried out by translating this to the input language of an existing model checker. Finally we present some formal verification results and describe how these could be complemented by simulation-based testing and realworld end-user validation in order to increase the practical and perceived safety and trustworthiness of robotic assistants
A Sequential Mixed Method Study of Employee Job Satisfaction in Upscale Restaurants, Malaysia
The study determines the main factors affecting job satisfaction in upscale restaurants and their degree of comparative influence. The research initially involves qualitative data analysis of 20 interviews with restaurant employees representing five upscale restaurants in Kuala Lumpur (KL), followed by structural equation modeling of data retrieved from 368 questionnaires from 16 KL restaurants. The impact variance of four main determinants of job satisfaction are revealed, where the âworking environmentâ has the highest impact, followed by âpayment and compensation,â âpromotionâ, and finally, âworkplace fairnessâ. Crucially, âworkplace relationshipsâ have a moderating effect on the relationship between the âwork environmentâ and job satisfaction, implicating industry-applied recommendations to strengthen job satisfaction levels
Landau and Ott scaling for the kinetic energy density and the low conventional superconductors, and Nb
The scaling approach recently proposed by Landau and Ott for isothermal
magnetization curves is extended to the average kinetic energy density of the
condensate. Two low superconductors, Nb and are studied
and their isothermal reversible magnetization shown to display Landau and Ott
scaling. Good agreement is obtained for the upper critical field ,
determined from the Abrikosov approximation for the reversible region (standard
linear extrapolation of the magnetization curve), and from the maximum of the
kinetic energy curves. For the full range of data, which includes the
irreversible region, the isothermal curves for show an
impressive collapse into a single curve over the entire range of field
measurements. The Nb isothermal curves exhibit the interesting
feature of a constant and temperature independent minimum value
A Robust Solution Procedure for Hyperelastic Solids with Large Boundary Deformation
Compressible Mooney-Rivlin theory has been used to model hyperelastic solids,
such as rubber and porous polymers, and more recently for the modeling of soft
tissues for biomedical tissues, undergoing large elastic deformations. We
propose a solution procedure for Lagrangian finite element discretization of a
static nonlinear compressible Mooney-Rivlin hyperelastic solid. We consider the
case in which the boundary condition is a large prescribed deformation, so that
mesh tangling becomes an obstacle for straightforward algorithms. Our solution
procedure involves a largely geometric procedure to untangle the mesh: solution
of a sequence of linear systems to obtain initial guesses for interior nodal
positions for which no element is inverted. After the mesh is untangled, we
take Newton iterations to converge to a mechanical equilibrium. The Newton
iterations are safeguarded by a line search similar to one used in
optimization. Our computational results indicate that the algorithm is up to 70
times faster than a straightforward Newton continuation procedure and is also
more robust (i.e., able to tolerate much larger deformations). For a few
extremely large deformations, the deformed mesh could only be computed through
the use of an expensive Newton continuation method while using a tight
convergence tolerance and taking very small steps.Comment: Revision of earlier version of paper. Submitted for publication in
Engineering with Computers on 9 September 2010. Accepted for publication on
20 May 2011. Published online 11 June 2011. The final publication is
available at http://www.springerlink.co
A possible role for the merger of clusters/voids in the cosmological expansion
In this study, we use the merger process of clusters/voids in the role of
variable dark energy fluid to alleviate the Hubble tension, which can lead to a
balance in the cosmological expansion rate. To reach this target, we will
introduce a modified form of energy density for cosmic fluid with the quadratic
equation of state, and then we obtain Hubble, deceleration parameters, and
luminosity distance for this fluid. To obtain the merger factor and other
parameters of our model, we utilize the NONLINEARMODELFIT function within
MATHEMATICA. By consideration of the local and global measurements of , and the equation of state parameter as the priory values and fitting
our model with Observational Hubble Data (OHD) measurements, we will show that
the merger of clusters/voids plays the role of balancing the cosmic expansion
rate. Also, it will be shown that the model is more compatible than CDM with
the standard model to describe the accelerating universe.Comment: 7 pages, 4 figures, 3 tables, According to the version accepted in
MNRA
Experimental observation of high field diamagnetic fluctuations in Niobium
We have performed a magnetic study of a bulk metallic sample of Nb with
critical temperature K. Magnetization versus temperature (M {\it
vs} T) data obtained for fixed magnetic fields above 1 kOe show a
superconducting transition which becomes broader as the field is increased. The
data are interpreted in terms of the diamagnetic lowest Landau level (LLL)
fluctuation theory. The scaling analysis gives values of the superconducting
transition temperature consistent with % . We search for
universal 3D LLL behavior by comparing scaling results for Nb and YBaCuO, but
obtain no evidence for universality.Comment: 5 pages, 6 figures, Accepted for publication in Phys.Rev.
The Social, Psychological and Economic Impact of Car Accidents on the Victims' Families
The study aimed at investigating the resulting effects on the families victims of car accidents in Jordan. The study focused on the social, economic and particularly on the psychological effect as it is the most influential on such families who get depression and anxiety. As car accidents do not stop the study attempted to answer the following question: 1-    The social effects of car accidents on the families victims. 2-    The psychological effects of car accidents on the families victims. 3-    The economic effects of car accidents on the families victims. To answer those question, a questionnaire consisted of (17) items delivered into the areas of the study was used.    The population of the study was the Jordanian community. The sample consisted of (250) young male and female whose families were exposed to different car accidents in the year 2012, (135) males and (115) females. The findings showed that the most influential effects on the families were losing the father where the family became in need to be cared about by different areas which caused them anxiety, depression and shocks that lead those families to separation, deviances and shame. This is because of they got a disable member and the high expenses of medical treatment for the injuries resulted from car accidents. As for minimizing the suffering families victims by holding courses and debates to educate people about road regulation. In addition, the government donated such families financial and spiritual help. Keywords: Car accident, Jordan society, Social effects of car accidents, Psychological effects of car accidents, Economic effects of car accident
PlackettâBurman randomization method for Bacterial Ghosts preparation form E. coli JM109
AbstractPlackettâBurman randomization method is a conventional tool for variables randomization aiming at optimization. Bacterial Ghosts (BGs) preparation has been recently established using methods other than the E lysis gene. The protocol has been based mainly on using critical concentrations from chemical compounds able to convert viable cells to BGs. The Minimum Inhibition Concentration (MIC) and the Minimum Growth Concentration (MGC) were the main guide for the BGs preparation. In this study, Escherichia coli JM109 DEC has been used to produce the BGs following the original protocol. The study contained a detail protocol for BGs preparation that could be used as a guide
Extensions of Weak PS-Rings
In this paper, we prove that, under mild conditions, if R is a right weak PS-ring, then so does the skew inverse power series ring R[[xâ1;Îą,δ]], the skew generalized power series ring R[[S,Ď]], and the differential inverse power series ring R[[xâ1;δ]]
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