9,840 research outputs found
CP-odd Phase Correlations and Electric Dipole Moments
We revisit the constraints imposed by electric dipole moments (EDMs) of
nucleons and heavy atoms on new CP-violating sources within supersymmetric
theories. We point out that certain two-loop renormalization group corrections
induce significant mixing between the basis-invariant CP-odd phases. In the
framework of the constrained minimal supersymmetric standard model (CMSSM), the
CP-odd invariant related to the soft trilinear A-phase at the GUT scale,
theta_A, induces non-trivial and distinct CP-odd phases for the three gaugino
masses at the weak scale. The latter give one-loop contributions to EDMs
enhanced by tan beta, and can provide the dominant contribution to the electron
EDM induced by theta_A. We perform a detailed analysis of the EDM constraints
within the CMSSM, exhibiting the reach, in terms of sparticle spectra, which
may be obtained assuming generic phases, as well as the limits on the CP-odd
phases for some specific parameter points where detailed phenomenological
studies are available. We also illustrate how this reach will expand with
results from the next generation of experiments which are currently in
development.Comment: 31 pages, 21 eps figures; v2: additional remarks on 2-loop threshold
corrections and references added; v3: typos corrected, to appear in Phys.
Rev.
Mediating Cognitive Transformation with VR 3D Sketching during Conceptual Architectural Design Process
Communications for information synchronization during the conceptual design phase require designers to employ more intuitive digital design tools. This paper presents findings of a feasibility study for using VR 3D sketching interface in order to replace current non-intuitive CAD tools. We used a sequential mixed method research methodology including a qualitative case study and a cognitive-based quantitative protocol analysis experiment. Foremost, the case study research was conducted in order to understand how novice designers make intuitive decisions. The case study documented the failure of conventional sketching methods in articulating complicated design ideas and shortcomings of current CAD tools in intuitive ideation. The case study’s findings then became the theoretical foundations for testing the feasibility of using VR 3D sketching interface during design. The latter phase of study evaluated the designers’ spatial cognition and collaboration at six different levels: “physical-actions”, “perceptualac ons”, “functional-actions”, “conceptual-actions”, “cognitive synchronizations”, and “gestures”. The results and confirmed hypotheses showed that the utilized tangible 3D sketching interface improved novice designers’ cognitive and collaborative design activities. In summary this paper presents the influences of current external representation tools on designers’ cognition and collaboration as well as providing the necessary theoretical foundations for implementing VR 3D sketching interface. It contributes towards transforming conceptual architectural design phase from analogue to digital by proposing a new VR design interface. The paper proposes this transformation to fill in the existing gap between analogue conceptual architectural design process and remaining digital engineering parts of building design process hence expediting digital design process
Efek Kualitas Kerja dalam Mengatasi Gap antara Kompetensi Kepemimpinan terhadap Kinerja
Peneliti ini bertujuan untuk mengetahui pengaruh kompetensi kepemimpinan terhadap Kualitas kerja, pengaruh kualitas kerja terhadap kinerja pegawai, dan pengaruh kompetensi kepemimpinan terhadap kinerja pegawai dengan kualitas kerja sebagai variabel mediasi. Populasi dalam penelitian ini sebesar 215 dengan sampel sebanyak 150 orang responden yang dipilih dengan metode Stratified Proportional Random Sampling model dianalisis dengan Structural Equation Modelling (SEM) dengan bantuan AMOS versi 20. Hasil analisis membuktikan bahwa kompetensi kepemimpinan berpengaruh positif dan signifikan terhadap kinerja pegawai dengan nilai koefisien sebesar 3,100, Kompetensi kepemimpinan berpengaruh positif dan signifikan terhadap kinerja pegawai, kompetensi kepemimpinan berpengaruh terhadap kualitas kerja dan kompetensi berpengaruh terhadap kinerja pagawai melalui kualitas kerja sebagai variabel mediasai. Hasil ini menunjukkan bahwa variabel kualitas kerja berperan secara signfikan sebagai variabel mediasi antara kompetensi kepemimpinan terhadap kinerja pegawai
Kinematic Modelling of FES Induced Sit-to-stand Movement in Paraplegia
FES induced movements from indication is promising due to encouraging results being obtained by scholars. The kinematic model usually constitute the initial phase towards achieving the segmental dynamics of any rigid body system. It can be used to ascertain that the model is capable of achieving the desired goal. The dynamic model builds on the kinematic model and is usually mathematically cumbersome depending on the number of degrees-of-freedom. This paper presents a kinematic model applicable for human sit-to-stand movement scenario that will be used to obtain the dynamic model the FES induced movement in a later study. The study shows that the 6 DOF conceptualized sit-to-stand movement can be achieved conveniently using 4 DOF. The 4 DOF has an additional joint compared to similar earlier works which makes more it accurate and flexible. It is more accurate in the sense that it accommodates additional joint i.e. the neck joint whose dynamics could be captured. And more flexible in the sense that if future research uncover more contributions by the segments it can be easily incorporated including that of other segments e.g. the trunk, neck and upper limbs
Proton-nucleus total reaction cross sections in the optical limit Glauber theory: Subtle dependence on the equation of state of nuclear matter
We calculate the proton-nucleus total reaction cross sections at different
energies of incident protons within the optical limit approximation of the
Glauber theory. The isospin effect has been taken into account. The nucleon
distribution is obtained in the framework of macroscopic nuclear models in a
way depending on the equation of state of uniform nuclear matter near the
saturation density. We find that at an energy of order 40 MeV, the reaction
cross section calculated for neutron- rich isotopes significantly increases as
the parameter L characterizing the density dependence of the symmetry energy
increases, while at energies of order 300 and 800 MeV, it is almost independent
of L. This is a feature of the optical limit Glauber theory in which an
exponential dependence of the reaction cross section on the neutron skin
thickness remains when the total proton-neutron cross section is small enough.Comment: 5 pages, 4 figure
Development of Low-Cost Current Controlled Stimulator for Paraplegics
A spinal cord injury (SCI) has a severe impact on human life in general as well as on the physical status and condition. The use of electrical signals to restore the function of paralyzed muscles is called functional electrical stimulation (FES). FES is a promising way to restore mobility to SCI by applying low-level electrical current to the paralyzed muscles so as to enhance that person’s ability to function and live independently. However, due to the limited number of commercially available FES assisted exerciser systems and their rather high cost, the conventional devices are unaffordable for most peoples. It is also inconvenient because of wired based system that creates a limitation in performing exercise. Thus, this project is concerned with the development of low-cost current controlled stimulator mainly for the paraplegic subjects. The developed device is based on a microcontroller, wireless based system using Zigbee module, voltage-to-current converter circuit and should produce proper monopolar and bipolar current pulses, pulse trains, arbitrary current waveforms, and a trigger output for FES applications. This device has been developed as in the new technique of the stimulator development with low cost and one of the contributing factors in Rehabilitation Engineering for patients with SCI
A Numerical Algorithm for Solving Stiff Ordinary Differential Equations
An advanced method using block backward differentiation formula (BBDF) is introduced with efficient strategy in choosing the step
size and order of the method. Variable step and variable order block backward differentiation formula (VSVO-BBDF) approach is
applied throughout the numerical computation.The stability regions of the VSVO-BBDFmethod are investigated and presented in
distinct graphs.The improved performances in terms of accuracy and computation time are presented in the numerical results with
different sets of test problems. Comparisons are made between the proposed method and MATLAB’s suite of ordinary differential
equations (ODEs) solvers, namely, ode15s and ode23s
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