A mixture model approach for formant tracking and the robustness of student's-t distribution

We address the problem of robust formant tracking in continuous speech in the presence of additive noise. We propose a new approach based on mixture modeling of the formant contours. Our approach consists of two main steps: (i) Computation of a pyknogram based on multiband amplitude-modulation/frequency-modulation (AM/FM) decomposition of the input speech; and (ii) Statistical modeling of the pyknogram using mixture models. We experiment with both Gaussian mixture model (GMM) and Student's-t mixture model (tMM) and show that the latter is robust with respect to handling outliers in the pyknogram data, parameter selection, accuracy, and smoothness of the estimated formant contours. Experimental results on simulated data as well as noisy speech data show that the proposed tMM-based approach is also robust to additive noise. We present performance comparisons with a recently developed adaptive filterbank technique proposed in the literature and the classical Burg's spectral estimator technique, which show that the proposed technique is more robust to noise.

System Ho-Rh-O: Phase Equilibria, Chemical Potentials and Gibbs Energy of Formation of HoRhO3

The thermodynamic properties of the HoRhO3 were determined in the temperature range from 900 to 1300 K by using a solid-state electrochemical cell incorporating calcia-stabilized zirconia as the electrolyte. The standard Gibbs free energy of formation of orthorhombic perovskite HoRhO3, from Ho2O3 with C-rare earth structure and Rh2O3 with orthorhombic structure, can be expressed by the equation; Delta G(f)degrees((ox)) (+/- 78)/(J/mol) = -50535 + 3.85(T/K) Using the thermodynamic data of HoRhO3 and auxiliary data for binary oxides from the literature, the phase relations in the Ho-Rh-O system were computed at 1273 K. Thermodynamic data for intermetallic phases in the binary Ho-Rh were estimated from experimental enthalpy of formation for three compositions from the literature and Miedema's model, consistent with the phase diagram. The oxygen potential-composition diagram and three-dimensional chemical potential diagram at 1273 K, and temperature-composition diagrams at constant oxygen partial pressures were computed for the system Ho-Rh-O. The decomposition temperature of HoRhO3 is 1717(+/- 2) K in pure O-2 and 1610(+/- 2) K in air at a total pressure p(o) = 0.1 MPa.

System Gd-Rh-O: Thermodynamics and phase relations

Thermodynamic properties of GdRhO3 are investigated in the temperature range from 900 to 1300 K by employing a solid-state electrochemical cell, incorporating calcia-stabilized zirconia as the electrolyte. The standard Gibbs free energy of formation of GdRhO3 from component binary oxide Gd2O3 with C-rare earth structure and Rh2O3 with orthorhombic structure can be expressed as; Delta G(f(ox))(o)(+/- 60)/J mol(-1) = -56603 + 3.78(T/K) Based on the thermodynamic information on GdRhO3 from experiment and auxiliary data for binary oxides from the literature and estimated properties of Gd-Rh alloys, phase relations are computed for the system Gd-Rh-O at 1273 K. Gibbs free energies for intermetallic phases in the binary Gd-Rh are evaluated using calorimetric data available in the literature for two compositions and Miedema's model, consistent with the binary phase diagram. Isothermal section of the ternary phase diagram, oxygen potential-composition diagram and a 3-D chemical potential diagram for the system Gd-Rh-O at 1273 K are developed. Phase relations in the ternary Gd-Rh-O are also computed as a function of temperature at constant oxygen partial pressures. The ternary oxide, GdRhO3 decomposes to Gd2O3 with B-rare earth structure, metallic Rh and O-2 at 1759(+/- 2) K in pure O-2 and 1649(+/- 2) K in air at a total pressure P-0 -0.1 MPa. (c) 2012 Elsevier B.V. All rights reserved.

MAPS: midline analysis and propagation of segmentation

Scenic word images undergo degradations due to motion blur, uneven illumination, shadows and defocussing, which lead to difficulty in segmentation. As a result, the recognition results reported on the scenic word image datasets of ICDAR have been low. We introduce a novel technique, where we choose the middle row of the image as a sub-image and segment it first. Then, the labels from this segmented sub-image are used to propagate labels to other pixels in the image. This approach, which is unique and distinct from the existing methods, results in improved segmentation. Bayesian classification and Max-flow methods have been independently used for label propagation. This midline based approach limits the impact of degradations that happens to the image. The segmented text image is recognized using the trial version of Omnipage OCR. We have tested our method on ICDAR 2003 and ICDAR 2011 datasets. Our word recognition results of 64.5% and 71.6% are better than those of methods in the literature and also methods that competed in the Robust reading competition. Our method makes an implicit assumption that degradation is not present in the middle row.

Analysis of size quantization and temperature effects on the threshold voltage of thin silicon film double-gate metal-oxide-semiconductor field-effect transistor (MOSFET)

In this paper, we analyze the combined effects of size quantization and device temperature variations (T = 50K to 400 K) on the intrinsic carrier concentration (n(i)), electron concentration (n) and thereby on the threshold voltage (V-th) for thin silicon film (t(si) = 1 nm to 10 nm) based fully-depleted Double-Gate Silicon-on-Insulator MOSFETs. The threshold voltage (V-th) is defined as the gate voltage (V-g) at which the potential at the center of the channel (Phi(c)) begins to saturate (Phi(c) = Phi(c(sat))). It is shown that in the strong quantum confinement regime (t(si) <= 3nm), the effects of size quantization far over-ride the effects of temperature variations on the total change in band-gap (Delta E-g(eff)), intrinsic carrier concentration (n(i)), electron concentration (n), Phi(c(sat)) and the threshold voltage (V-th). On the other hand, for t(si) >= 4 nm, it is shown that size quantization effects recede with increasing t(si), while the effects of temperature variations become increasingly significant. Through detailed analysis, a physical model for the threshold voltage is presented both for the undoped and doped cases valid over a wide-range of device temperatures, silicon film thicknesses and substrate doping densities. Both in the undoped and doped cases, it is shown that the threshold voltage strongly depends on the channel charge density and that it is independent of incomplete ionization effects, at lower device temperatures. The results are compared with the published work available in literature, and it is shown that the present approach incorporates quantization and temperature effects over the entire temperature range. We also present an analytical model for V-th as a function of device temperature (T). (C) 2013 AIP Publishing LLC.

Interplay Between Optimal Selection Scheme, Selection Criterion, and Discrete Rate Adaptation in Opportunistic Wireless Systems

An opportunistic, rate-adaptive system exploits multi-user diversity by selecting the best node, which has the highest channel power gain, and adapting the data rate to selected node's channel gain. Since channel knowledge is local to a node, we propose using a distributed, low-feedback timer backoff scheme to select the best node. It uses a mapping that maps the channel gain, or, in general, a real-valued metric, to a timer value. The mapping is such that timers of nodes with higher metrics expire earlier. Our goal is to maximize the system throughput when rate adaptation is discrete, as is the case in practice. To improve throughput, we use a pragmatic selection policy, in which even a node other than the best node can be selected. We derive several novel, insightful results about the optimal mapping and develop an algorithm to compute it. These results bring out the inter-relationship between the discrete rate adaptation rule, optimal mapping, and selection policy. We also extensively benchmark the performance of the optimal mapping with several timer and opportunistic multiple access schemes considered in the literature, and demonstrate that the developed scheme is effective in many regimes of interest.

En Masse relay selection algorithms for multi-source, multi-relay, decode-and-forward cooperative systems

Opportunistic relay selection in a multiple source-destination (MSD) cooperative system requires quickly allocating to each source-destination (SD) pair a suitable relay based on channel gains. Since the channel knowledge is available only locally at a relay and not globally, efficient relay selection algorithms are needed. For an MSD system, in which the SD pairs communicate in a time-orthogonal manner with the help of decode-and-forward relays, we propose three novel relay selection algorithms, namely, contention-free en masse assignment (CFEA), contention-based en masse assignment (CBEA), and a hybrid algorithm that combines the best features of CFEA and CBEA. En masse assignment exploits the fact that a relay can often aid not one but multiple SD pairs, and, therefore, can be assigned to multiple SD pairs. This drastically reduces the average time required to allocate an SD pair when compared to allocating the SD pairs one by one. We show that the algorithms are much faster than other selection schemes proposed in the literature and yield significantly higher net system throughputs. Interestingly, CFEA is as effective as CBEA over a wider range of system parameters than in single SD pair systems.

Optimal Joint Antenna Selection and Power Adaptation in Underlay Cognitive Radios

Transmit antenna selection (AS) is a popular, low hardware complexity technique that improves the performance of an underlay cognitive radio system, in which a secondary transmitter can transmit when the primary is on but under tight constraints on the interference it causes to the primary. The underlay interference constraint fundamentally changes the criterion used to select the antenna because the channel gains to the secondary and primary receivers must be both taken into account. We develop a novel and optimal joint AS and transmit power adaptation policy that minimizes a Chernoff upper bound on the symbol error probability (SEP) at the secondary receiver subject to an average transmit power constraint and an average primary interference constraint. Explicit expressions for the optimal antenna and power are provided in terms of the channel gains to the primary and secondary receivers. The SEP of the optimal policy is at least an order of magnitude lower than that achieved by several ad hoc selection rules proposed in the literature and even the optimal antenna selection rule for the case where the transmit power is either zero or a fixed value.

Analytical Determination of Residual Strength and Linkup Strength for Flat Panels, with Multiple Site Damage

The problem of multiple site damage in aged airplane fuselage is handled in this paper. The analytical and numerical procedures used for the estimation of the strength of a flat panel with such multi-site damage are presented. Further, numerical results are presented on the residual strength of the panel using fracture mechanics-based approach and the stress levels when the leading crack is likely to link up with multiple site damage cracks. The presence of multiple site damage cracks in the vicinity of leading crack significantly decreases the residual strength of the panel. The model is verified using experimental data from the open literature and the predictions are in good agreement with the measured residual strength.

Influence of crystallographic texture and microstructure on elastic modulus of steels

In this paper the effects of crystallographic texture and microstructure on the elastic modulus of different grades of steel have been collected from the available literature and put in one place. It is expected that this will help researchers in their understanding of both the fundamental and the practical aspects of the different grades of steel used for various purposes.

On the Room Temperature Ferromagnetic and Ferroelectric Properties of Pb(Fe1/2Nb1/2)O-3

We report the origin of room temperature (RT) ferromagnetic and ferroelectric properties of Pb(Fe1/2Nb1/2)O-3 (PFN) ceramic sample prepared by modified solid-state reaction synthesis by a single-step method, based on X-ray diffraction (XRD), neutron diffraction (ND), Mossbauer spectroscopy and electron paramagnetic resonance (EPR) spectroscopy results. Formation of single-phase monoclinic PFN ceramic with Cm space group was confirmed by XRD and ND at RT. The morphology studied by scanning electron microscopy (SEM) confirmed uniform microstructure of the sample with average grain size of similar to 2 mu m. The ND, Mossbauer spectroscopy, M-H loop and EPR studies were carried out to confirm the existence of weak ferromagnetism at RT. A clear opening of hysteresis (M-H) loop is evidenced as the existence of weak ferromagnetism at RT. EPR spectrum clearly shows the ferromagnetism through a good resonance signal. The symmetric EPR line shape with g = 1.9895 observed in PFN sample was identified to be due to Fe3+ ions. Mossbauer spectroscopy at RT shows superparamagnetic behaviour with presence of Fe in 3+ valence state. Ferroelectric P-E loops on PFN at RT confirm the existing ferroelectric ordering. Our observation is in agreement with literature, and it supports that the origin of ferromagnetism and ferroelectricity is isolated, i.e. from different regions in the sample. Our results do not support the multiferroic nature of PFN at RT.

Innovative capabilities, entrepreneurial process and the dynamic growth of university spin-outs: A process-oriented study with evidence from China

This research aims to develop a conceptual framework in order to enquire into the dynamic growth process of University Spin-outs (hereafter referred to as USOs) in China, attempting to understand the capabilities configuration that are necessary for the dynamic growth. Based on the extant literature and empirical cases, this study attempts to address the question how do USOs in China build and configure the innovative capabilities to cope with the dynamic growth. This paper aims to contribute to the existing literature by providing a theoretical discussion of the USOs' dynamic entrepreneurial process, by investigating the interconnections between innovation problem-solving and the required configuration of innovative capabilities in four growth phases. Further, it presents a particular interest on the impact to the USOs' entrepreneurial innovation process by the integrative capabilities, in terms of knowledge integration, alliance, venture finance and venture governance. To date, studies that have investigated the dynamic development process of USOs in China and have recognized the heterogeneity of USOs in terms of capabilities that are required for rapid growth still remain sparse. Addressing this research gap will be of great interest to entrepreneurs, policy makers, and venture investors. ©2009 IEEE.

The question of ethical decision in marketing and ethics

Resumen: Mientras que el marketing está asociado con prácticas negativas que involucran la explotación y la deshonestidad, Anton Jamnik afirma la necesidad de crear una teoría ética para éste. El artículo intenta brindar, por un lado, un breve bosquejo de las principales corrientes de la literatura de la ética del marketing y, por otro, participar de su desarrollo. El autor analiza los desafíos éticos que sur girán en el futuro, provenientes de tres fuentes distintas: las innovaciones tecnológicas, la influencia de la competencia global y la expansión de las actividades de mercado en áreas no tradicionales. Esto requerirá el desarrollo de una ética normativa realista. Para concluir, explica que la ética del marketing debería analizar hasta qué punto ha sido exitosa a la hora de resolver los desafíos éticos del mundo actual.

Interaction between a strategic mass media firm and a government

Resumen: Este artículo intenta teorizar acerca de la dinámica entre los medios masivos de comunicación y los gobiernos de los países latinoamericanos. Si bien en la última década los gobiernos atacaron públicamente a los medios de comunicación, se afirma que no se dio por las razones que dicen, sino más bien por asuntos económicos. Por lo tanto, se ha diseñado un modelo utilizando el método de “principal” vs “incumbente”, donde se alcanzará un equilibrio de Nash perfecto en subjuegos. Además de esto, se realiza un repaso por la literatura conocida, y concluye señalando las fortalezas y debilidades del modelo propuesto.

Shock slip-relations for thermal and chemical nonequilibrium flows

This paper appears to be the first where the multi-temperature shock slip-relations for the thermal and chemical nonequilibrium flows are derived. The derivation is based on analysis of the influences of thermal nonequilibrium and viscous effects on the mass, momentum and energy flux balance relations at the shock wave. When the relaxation times for all internal energy modes tend to sere, the multi-temperature shock slip-relations are converted into single-temperature ones for thermal equilibrium hows. The present results can be applied to flows over vehicles of different geometries with or without angles of attack. In addition, the present single-temperature shock slip-relations are compared with those in the literature, and Some defects and limitations in the latter are clarified.