Portable Dextrous Force Feedback Master for robot telemanipulation (PDMFF)

A major drawback of open loop masters is a lack of force feedback, limiting their ability to perform complex tasks such as assembly and repair. Researchers present a simple dextrous force feedback master for computer assisted telemanipulation. The device is compact, portable and can be held in the operator hand, without the need for a special joystick or console. The system is capable of both position feed forward and force feedback, using electronic position sensors and a pneumatic micro-actuator. The level of forces exercised by the pneumatic actuator is such that near rigidity may be attained. Experimental results showing good system linearity and small time lag are given

The Interaction of Quantum Gravity with Matter

The interaction of (linearized) gravitation with matter is studied in the causal approach up to the second order of perturbation theory. We consider the generic case and prove that gravitation is universal in the sense that the existence of the interaction with gravitation does not put new constraints on the Lagrangian for lower spin fields. We use the formalism of quantum off-shell fields which makes our computation more straightforward and simpler.Comment: 25 page

The exotic Galilei group and the "Peierls substitution"

Taking advantage of the two-parameter central extension of the planar Galilei group, we construct a non relativistic particle model in the plane. Owing to the extra structure, the coordinates do not commute. Our model can be viewed as the non-relativistic counterpart of the relativistic anyon considered before by Jackiw and Nair. For a particle moving in a magnetic field perpendicular to the plane, the two parameters combine with the magnetic field to provide an effective mass. For vanishing effective mass the phase space admits a two-dimensional reduction, which represents the condensation to collective ``Hall'' motions and justifies the rule called ``Peierls substitution''. Quantization yields the wave functions proposed by Laughlin to describe the Fractional Quantum Hall Effect.Comment: Revised version, to appear in Phys. Lett. B. Souriau's scheme and its relation of with the Faddeev-Jackiw hamiltonian reduction is explained. 11 pages, LaTex, no figure

MODERN METHODS FOR FOOD PRODUCTS PRESERVATION

Bacteria, molds and yeasts are microorganisms that play an essential role in spoiling food. Food products preservation technologies are intended to reduce the intensity of the activity of pathogenic microorganisms that generate decomposition processes. From the point of view of food technologies, heat treatments (pasteurization, sterilization) are the main way of preserving food. The trend is to minimize or replace heat treatments with nonthermal, non-destructive methods, in order to preserve the freshness, nutritional and bioactive value of the food products. This paper presents the working principles and the effects of various modern methods of preservation, thermal and athermal, on food

Methods to elicit probability distributions from experts: a systematic review of reported practice in health technology assessment

The final publication is available at Springer via the DOI in this record.BACKGROUND: Elicitation is a technique that can be used to obtain probability distribution from experts about unknown quantities. We conducted a methodology review of reports where probability distributions had been elicited from experts to be used in model-based health technology assessments. METHODS: Databases including MEDLINE, EMBASE and the CRD database were searched from inception to April 2013. Reference lists were checked and citation mapping was also used. Studies describing their approach to the elicitation of probability distributions were included. Data was abstracted on pre-defined aspects of the elicitation technique. Reports were critically appraised on their consideration of the validity, reliability and feasibility of the elicitation exercise. RESULTS: Fourteen articles were included. Across these studies, the most marked features were heterogeneity in elicitation approach and failure to report key aspects of the elicitation method. The most frequently used approaches to elicitation were the histogram technique and the bisection method. Only three papers explicitly considered the validity, reliability and feasibility of the elicitation exercises. CONCLUSION: Judged by the studies identified in the review, reports of expert elicitation are insufficient in detail and this impacts on the perceived usability of expert-elicited probability distributions. In this context, the wider credibility of elicitation will only be improved by better reporting and greater standardisation of approach. Until then, the advantage of eliciting probability distributions from experts may be lost.NIH

Analysis of the electrical and thermal behaviour of Li-ion batteries using 0D and 3D-CFD approaches with validation on experimental data

Due to their characteristics, lithium-ion cells are the reference in the construction of a battery pack for electric vehicles (EVs). Despite this, their use is strongly affected by the operating temperature because the materials they are made of are thermally stable only in a relatively limited range around ambient temperature. Cell modelling and simulation become therefore essential in the design of the cell, of the battery pack and of its auxiliary systems to optimize performance while maintaining sufficient safety margins. In the present study, two zero-dimensional equivalent circuit models of a commercial Li-ion cell are developed and tuned in order to predict the electrical and thermal behaviour of the cell. The models are validated and compared with experimental data found in the scientific literature referring to both dynamic and static tests. This comparison shows the importance of tuning the model parameters, which are decisive for the accuracy of the simulation. Using a commercial tool dedicated to battery modelling, a three-dimensional model is then developed to investigate the electrical and thermal behaviour of the cell from a spatial point of view. The results obtained are aligned with those found in the scientific literature. With the present work, it has been possible to simulate and analyse the global behaviour of the cell (0D model) as well as its detailed behaviour (3D model) using relatively modest computational resources, thus constituting a solid base for more complex modelling such as that of a battery pack and its cooling system

EXPERIMENTAL RESEARCH ON DETERMINATION OF DEFORMATIONS IN THE CUTTING PROCESS IN WET SANDY SOILS

The active parts of tillage equipment must be checked for wear resistance, under different conditions working with the soil, so that the average life span should be determined wear resistance, to ensure timely changes of parts. Research in the field has shown that there are at least two main forces acting on the active parts: impact and friction, the action of these forces causes wear. In order to test the tillage knives in laboratory conditions, was used a stand made by INMA Bucharest. With the help of this stand, the deformations in the cutting process were determined in different working conditions: at a certain working speed and at a certain humidity of the sandy soil

CONSIDERATIONS REGARDING THE IMPORTANCE OF THE SORTING OPERATION OF FRUITS AND VEGETABLES

For the normal development of daily activity and maintaining health, the body needs a certain amount of energy and complete nutritional factors (proteins, carbohydrates, lipids, vitamins, minerals, water). They are obtained from food, fruits and vegetables occupying a prominent place as a natural source of carbohydrates, alkalizing mineral salts, vitamins and water. Conditioning involves a set of operations aimed at bringing the products to the characteristics provided by standards, specific to a certain direction of capitalization. This article describes the operations included in the conditioning process, the role and importance of presorting and sorting fruits and vegetables, as well as equipment for these operations