711 research outputs found
Genetic and ampelographic identification of different grape varieties known as 'Tempranillo' in Rioja (Spain)
Research Note
Directional shift current in mirror-symmetric BCN
We present a theoretical study of the shift current in a noncentrosymmetric
polytype of graphitic BCN. We find that the photoconductivity near the
fundamental gap is strongly anisotropic due to the vanishing of particular
tensor components not foretold by point-group symmetry arguments; this is a
consequence of dipole selection rules imposed by mirror symmetry, which imply
that the relative parities between valence and conduction bands are key for
determining the directionality of the band-edge response. In addition, the
band-edge photoconductivity turns out to be rather large, with the peak value
occurring in an energy range suitable for optical manipulationComment: 7 pages, 4 figure
Inverting the Supersymmetric Standard Model Spectrum: from Physical to Lagrangian Ino Parameters
We examine the possibility of recovering the supersymmetric (and soft
supersymmetry breaking) Lagrangian parameters as direct {\em analytical}
expressions of appropriate physical masses, for the unconstrained (but CP and
R-parity conserving) minimal supersymmetric standard model. We concentrate
mainly on the algebraically non-trivial "inversion" for the ino parameters, and
obtain, for given values of , simple analytical expressions for the
, and parameters in terms of three arbitrary input physical
masses, namely either two chargino and one neutralino masses, or alternatively
one chargino and two neutralino masses. We illustrate and discuss in detail the
possible occurrence of ambiguities in this reconstruction. The dependence of
the resulting ino Lagrangian parameters upon physical masses is illustrated,
and some simple generic behaviour uncovered in this way. We finally briefly
sketch generalizing such an inversion to the full set of MSSM Lagrangian
parameters.Comment: Latex, 28 pages, 6 figures, 1 table, some typos corrected, one
paragraph extended in section 4.2. Version to appear in Phys. Rev.
Combining a hybrid robotic system with a bain-machine interface for the rehabilitation of reaching movements: A case study with a stroke patient
Reaching and grasping are two of the most affected functions after stroke. Hybrid rehabilitation systems combining Functional Electrical Stimulation with Robotic devices have been proposed in the literature to improve rehabilitation outcomes. In this work, we present the combined use of a hybrid robotic system with an EEG-based Brain-Machine Interface to detect the user's movement intentions to trigger the assistance. The platform has been tested in a single session with a stroke patient. The results show how the patient could successfully interact with the BMI and command the assistance of the hybrid system with low latencies. Also, the Feedback Error Learning controller implemented in this system could adjust the required FES intensity to perform the task
The (1+1)-dimensional Massive sine-Gordon Field Theory and the Gaussian Wave-functional Approach
The ground, one- and two-particle states of the (1+1)-dimensional massive
sine-Gordon field theory are investigated within the framework of the Gaussian
wave-functional approach. We demonstrate that for a certain region of the
model-parameter space, the vacuum of the field system is asymmetrical.
Furthermore, it is shown that two-particle bound state can exist upon the
asymmetric vacuum for a part of the aforementioned region. Besides, for the
bosonic equivalent to the massive Schwinger model, the masses of the one boson
and two-boson bound states agree with the recent second-order results of a
fermion-mass perturbation calculation when the fermion mass is small.Comment: Latex, 11 pages, 8 figures (EPS files
Precision SUSY Measurements at LHC
If supersymmetry exists at the electroweak scale, then it should be
discovered at the LHC. Determining masses, of supersymmetric particles however,
is more difficult. In this paper, methods are discussed to determine
combinations of masses and of branching ratios precisely from experimentally
observable distributions. In many cases such measurements alone can greatly
constrain the particular supersymmetric model and determine its parameters with
an accuracy of a few percent. Most of the results shown correspond to one year
of running at LHC at ``low luminosity'.Comment: 52 pages, Latex with 42 postscript figures. Postscript version also
at http://www-physics.lbl.gov/www/theorygroup/papers/39412.p
Design of an Information System for optimizing the Programming of nursing work shifts
Health institutions operate twenty-four hours a day, seven days a week. They face a demand that fluctuates daily. Unlike jobs with fixed hours and obligatory days off, in health, operational continuity is required. The allocation for nursing shifts generates a rotation of people for health services according to legal and casuistic guidelines. Assigning and planning shifts results in a workload that takes an average of five to six extra hours. Existing applications offer a partial solution because they do not consider the news and contingencies of a health service. A web application is presented that, given a list of nurses, historical shifts and restrictions, a work shift planning is generated. This application comes to support the current shift allocation method based on electronic spreadsheets. The development consists of two modules. The first module has a shift allocation algorithm developed in C ++ and the second module has a graphical interface. As a case study, a set of health services from Chile and Colombia was used. The services have a defined number of nurses, who work different shifts according to the role and need of the institution. The results obtained are similar to a historical one. The proposed system takes less time and delivers various files and parameters that can be useful for nurses, the service and the health institutio
Lean Manufacturing Production Management Model focused on Worker Empowerment aimed at increasing Production Efficiency in the textile sector
For companies operating within the garment manufacturing industry, having frequent downtimes in their production flows is an extremely common issue. In this context, a balanced production line is required to prevent high waiting times due to limited productive capacity. A well-balanced assembly line allows products to be produced in an optimum time while using less resources, such as machines, materials, or labour, since the right number of products is produced with the exact amount of resources, thus generating savings in production costs. This paper seeks to foster optimum resource allocation through the line balancing tool. Finally, to define a work methodology, best practices were selected, and a procedures manual was developed focusing on Standardization. Both tools were implemented after implementing changes to the company culture by means of the Employee Empowerment tool. As a result of this implementation, workers acquired greater accountability and control over the resources, methods, and equipment of their work areas. After the proposed improvements had been deployed, the company reported an increase of over 20% in production line quality, performance, and efficiency
SCOR Model for a Dual-Channel Supply Chain using Drop Shipping to Reduce Overstock in Small- and Medium-Sized Retail Enterprises
Sales are central to retail companies. One of the main problems for these companies is when products are sold later than expected, causing overstock due to lower inventory turnover, which increases inventory levels. Therefore, for many retailers, it is important to solve this problem. This is mostly applicable to companies engaged in sales; however, if we take into account the main supplier and the way they act within the supply chain, we must also consider an additional approach. Since online sales are a major innovation brought about by the new digital era, it is standard for sales strategies to focus on this new requirement of customers. In this way, the main supplier takes a leap forward on Internet sales, creating another sales channel. This is when companies under the supply chain start losing sales. According to the above, a dual supply chain model was suggested using the SCOR model and drop shipping. After the improvement proposal was implemented, the company reported a reduction of approximately S/13,000 when comparing the first quarter of 2018 to that of 2019
LEAN Production Management Model based on Organizational Culture to Improve Cutting Process Efficiency in a Textile and Clothing SME in Peru
El texto completo de este trabajo no estƔ disponible en el Repositorio AcadƩmico UPC por restricciones de la casa editorial donde ha sido publicado.In recent years, homegrown SMEs have had low production levels when compared with Chinese garment imports, losing their competitive advantage in the domestic market. SMEs represent 96% of garment companies in Peru and have a positive impact on the creation of jobs. The search for a technique to improve SME output was conducted in various studies; however, the efforts did not bear fruit over time. Thus, this article seeks to improve the low production efficiency in textile and clothing SMEs. Therefore, we proposed a model and validated it in the production area of a denim clothing manufacturing company in Peru. We conducted business diagnostics and found a production efficiency problem. Later, we adapted the Lean production management model to the prevailing organizational culture. The main result was that the company's production efficiency increased from 68% to 71%. Finally, employee commitment, along with the combination of the Lean model and organizational culture, allowed the improvements to stand the test of time after their implementation
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