Comments on ‘ Continued fraction methods for the reduction of discrete-time dynamic systems ’

The application of the continued expansion method about z=l in Example 1 of Shamesh (1974) is incorrect. The correct solution is given in this note     

A metric space for computer programs and the principle of computational least action

We define a normed metric space for computer programs and derive from it the Principle of Computational Least Action. In our model, programs follow trajectories determined by Newton’s equation of motion in an abstract computational phase space and generate computational action as they evolve. A program’s action norm is the L ₁-norm of its action function, and its distance from other programs is the distance derived from the action norm. The Principle of Computational Least Action states the goal of performance optimization as finding the program with the smallest action norm. We illustrate this principle by analyzing a simple program.

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Never blame the umpire – a review of Situation Awareness models and methods for examining the performance of officials in sport

As sport becomes more complex, there is potential for ergonomics concepts to help enhance the performance of sports officials. The concept of Situation Awareness (SA) appears pertinent given the requirement for officials to understand what is going on in order to make decisions. Although numerous models exist, none have been applied to examine officials, and only several recent examples have been applied to sport. This paper examines SA models and methods to identify if any have applicability to officials in sport (OiS). Evaluation of the models and methods identified potential applications of individual, team and systems models of SA. The paper further demonstrates that the Distributed Situation Awareness model is suitable for studying officials in fastball sports. It is concluded that the study of SA represents a key area of multidisciplinary research for both ergonomics and sports science in the context of OiS.

Practitioner Summary: Despite obvious synergies, applications of cognitive ergonomics concepts in sport are sparse. This is especially so for Officials in Sport (OiS). This article presents an evaluation of Situation Awareness models and methods, providing practitioners with guidance on which are the most suitable for OiS system design and evaluation.     

Necessary and sufficient conditions for the existence of positive definite solutions of the matrix equation X+A T X −2 A=I

Necessary and sufficient conditions for the matrix equation X+A ^T X ^?2 A=I to have a real symmetric positive definite solution X are derived. Based on these conditions, some properties of the matrix A as well as relations between the solution X and A are derived.     

A review of e-commerce literature on India and research agenda for the future

Firms across the globe have adopted e-commerce (EC) in their operations and have reaped benefits thereof. While firms in technologically developed countries like US and UK has deployed EC to its advantage, whereas firms in developing countries like India failed to follow the suit. Though it has been widely acknowledged by the researchers that the adoption of EC by businesses in developing countries is an important economic indicator of growth; many firms in India still have not realized the potential benefits of EC. This study examines the existing status of EC in India and reviews the available literature on E-commerce adoption in India and puts forth opportunities for future research. The study might serve as a starting point for further research in e-commerce in India.     

A dual-branch model for diagnosis of Parkinson’s disease based on the independent and joint features of the left and right gait

Applied Intelligence - Clinical diagnosis of Parkingson’s disease (PD) requires the physician to assess the patient’s gait and other symptoms. A dual-branch model is proposed in this...     

CUDA programs for the GPU computing of the Swendsen–Wang multi-cluster spin flip algorithm: 2D and 3D Ising,Potts, and XY models

We present sample CUDA programs for the GPU computing of the Swendsen–Wang multi-cluster spin flip algorithm. We deal with the classical spin models; the Ising model, the q$q$-state Potts model, and the classical XY model. As for the lattice, both the 2D (square) lattice and the 3D (simple cubic) lattice are treated. We already reported the idea of the GPU implementation for 2D models (Komura and Okabe, 2012). We here explain the details of sample programs, and discuss the performance of the present GPU implementation for the 3D Ising and XY models. We also show the calculated results of the moment ratio for these models, and discuss phase transitions.     

Continuous emotion estimation of facial expressions on JAFFE and CK+ datasets for human–robot interaction

Human–robot interaction was always based on estimation of human emotions from human facial expressions, voice and gestures. Human emotions were always categorized in a discretized manner, while we estimate facial images from common datasets for continuous emotions. Linear regression was used in this study which numerically quantizes human emotions as valence and arousal by displaying the raw images on the two-respective coordinate axis. The face image datasets from the Japanese female facial expression (JAFFE) dataset and the extended Cohn–Kanade (CK+) dataset were used in this experiment. Human emotions for the above-mentioned datasets were interpreted by 85 participants who were used in the experimentation. The best result from a series of experiments shows that the minimum of root mean square error for the JAFFE dataset was 0.1661 for valence and 0.1379 for arousal. The proposed method has been compared with previous methods such as songs, sentences, and it is observed that the proposed method for common datasets testing showed an outstanding emotion estimation performance.

     

Comments on ‘A necessary and sufficient condition for the positive-definiteness of interval symmetric matrices’

Shi and Gao (1986) gave a necessary and sufficient condition for the positive-definiteness of interval symmetric matrices. We point out that their result is not new and the assumptions can be less restrictive.     

Critical examination of recent assertions by Logo (2013) about the paper ‘Analytical and numerical solutions for a reliability based benchmark example’ (Rozvany and Maute 2011)

The aim of this Authors’ Reply is to examine critically certain assertions by Logo in a Discussion and in two conference papers about a publication by Rozvany and Maute on a reliability based benchmark example     

Comments on ‘A necessary and sufficient condition for the positive-detiniteness of interval symmetric matrices’

The main results obtained recently by Shi and Gao are already known and can be strengthened.     

Comments on the reply to comments on ‘State observers and state-feedback controllers for a class of non-linear systems’

Some further remarks seem necessary on the reply of Hauksdottir and Fenton (1990) to the present author's original comment (Birk 1990) on their paper (Hauksdottir and Fenton 1988).     

Comments on ‘Sufficient and necessary condition for the asymptotic stability of discrete linear interval systems’

In a recent paper by Jiang (1988), a necessary and sufficient condition for asymptotic stability of the interval matrix of discrete-time systems is presented. In this contribution it is shown that this condition is not true in general. A counter-example is given and additional remarks are made.     

A research initiative on the construction of innovative environments for teaching and learning. Montessori and Munari based psycho-pedagogical insights in computers and human behavior for the “new school”

Italians children-students live a strong technological gap among different education instances: on the one hand, they are attending schools technologically still to the '80 years, on the other hand, they can rely on hyper-technological domestic-family environments where videogames, smartphones, internet are always available. In the school, all learnings take place under the supervision of the teacher that stimulates, directs and corrects these important steps in the basic training. On the contrary, in the domestic environment the presence of technology is increasingly pervasive. These new technologies cognitively stimulate the children, but they entertain the little ones often alone and without the participation and supervision of an adult audience.Thus, the technology gap results in a pedagogical clash among different educational instances and this is the “space” addressed by our research initiative whose objective is the construction of innovative teaching and learning environments for children between 3 and 6 years of age. The specific quantitative outcomes can be defined with respect to three main families of indicators: measures to detect the use of learning environments; indicators of the level of satisfaction and involvement of the various involved actors; real impact on the socio-cognitive development of children produced by the introduction of methodologies and technologies.     

Quantifying repetitive hand activity for epidemiological research on musculoskeletal disorders – Part II: comparison of different methods of measuring force level and repetitiveness

The effect upon performance of the diroction-of-inotion relationship between a control and a display is shown to depend upon certain other features of the layout. When a rotary control knob is used in conjunction with a linear indicator, a clock wise movement of the control is expected to move the pointer upwards or to the right. This expectation is, however, weaker when the centre of rotation of the control is situated on tho line of movement of the display than when the control is situated to the side of tho line, so that the pointer moves in the same direction as tho nearest part of tho knob. The orientation of the display and tho position of the control have no effect apart from this relationship between them.     

On the Dependence of Discrete Ordinates Models for Layer Reflectance and Transmittance on Relative Optical Depth and Solar Zenith Angle

We investigate the effect of layer optical depth and solar zenith angle on recently developed discrete ordinates models for the diffuse reflectance and transmittance of an optically stationary atmospheric boundary layer. We start with a mathematical formulation of the atmospheric radiative transfer problems dealt with in this article, and we consider a discrete ordinates version of the governing equations. For the sake of continuity, we give a brief account of our recently developed models, and assuming steadiness with respect to the inherent optical properties, we work on the dependence of our models on two target parameters: the relative optical depth of the boundary layer and solar zenith angle. As a result, we get optimized relations for our models in terms of the target parameters. To illustrate the relevance of such relations, we present results of computer simulations using problem sets basic to solar-atmospheric science applications such as environmental remote sensing, radiation dosimetry, and solar power plants.