Comments on “Discrete-Time Adaptive Backstepping Nonlinear Control via High-Order Neural Networks”

The purpose of this comment is to point out some mistakes in the above paper. It is shown that the main results of the paper cannot stand in general. Also, it is pointed out that after some corrections, the proposed control algorithm is still applicable to a more simple system. For simplicity, all the symbols in this comment are the same as those in the above paper.     

Comments on “direct bilinear routh stability criteria for discrete systems”

The above paper¹ discusses useful Routh-like stability criteria for discrete systems. Unfortunately, however, previous work on the subject escaped the attention of the author. This note co-ordinates previous work with results obtained in the above paper. It also points out some of the more recent developments on the subject.     

Comments on “A class of proportional-integral sliding mode control with application to active suspension system”

In this note, we first show that Theorem 2 in the above paper is incorrect. Then, we also show that Theorem 1 is not enough to support the claim in the above paper that the proportional-integral sliding mode control method is more robust than the linear quadratic regulator method when applying on the active suspension system with mismatched uncertainties.     

CORRECTION TO “SINGULARITY COMPUTATION FOR ITERATIVE CONTROL OF NONLINEAR AFFINE SYSTEMS”

The ball‐on‐plate example in the above paper by the authors [3] contains a mistake in the vector field. This note presents the singularity result of the corrected vector field.     

Comments and improvement on “Robust control of state delayed systems with polytopic type uncertainties via parameter-dependent Lyapunov functionals”

The errors are pointed out in the above paper. And then, a new delay-dependent condition is presented for the robust stability of uncertain time-delay systems, which is an improvement on the corresponding results in the above paper.     

Erratum to “On the Synthesis of Haptic Textures” [Jun 08 527-536]

In the above titled paper (ibid., vol. 24, no. 3, pp. 527-536, Jun 08), it is stated in Sec. IV-D3 that the characteristic number of the first variant of the "god object" method applied to texture synthesis is 1. This statement is not always true, and clarification of this issue is presented here.     

Corrections to “Basins of Attraction in Fully Asynchronous Discrete-Time Discrete-State Dynamic Networks” [Mar 06 397-408]

This paper brings a correction to the formulation of the basins of fixed-point states of fully asynchronous discrete-time discrete-state dynamic networks presented in the above titled paper (ibid., vol. 17, no. 2, pp. 397-408, Mar 06). In our subsequent works on totally asynchronous systems, we have discovered that the formulation given in that previous paper lacks an additional condition. We present in this paper why the previous formulation is incomplete and give the correct formulation.     

Transformation ratio of “ring-dot” planar piezoelectric transformer

A piezoelectric transformer (PT) is a device, which can be used for transforming an ac voltage via ultrasonic vibrations. The best characteristics are achieved in the vicinity of mechanical vibration resonance. “Ring-dot” type design of homogeneously poled disk PT was originally proposed by Berlincourt. Only experimental data were published in preceding studies. An analytical continuum model is presented in this work. The effects of dimensions, material properties and electrical load on the voltage gain as well as on the efficiency are calculated. Hard lead zirconate titanate ceramics (PZT, APC841 type) was used for sample fabrication. Studied PTs typically attain transformation ratio equal 20 without load. For load impedance around 5 kΩ, the observed efficiency was above 90%, whereas the transformation ratio dropped down to the values around 2. The model correspondence with experiment is limited by employed approximations. Model limitations are discussed with respect to experimental data.     

Remarks on the application of the Keldysh theorem to the completeness of root subspace of non-self-adjoint operators and comments on “Spectral operators generated by Timoshenko beam model”

In this note, we show, by means of an example, that the assumption of compactness in the Keldysh theorem in proving the completeness of root subspaces of non-self-adjoint operators cannot be ignored. This indicates a gap of the above mentioned paper and many other related papers in the proof of completeness for the root subspaces of beam-related problems.     

Remarks on “Measuring Ambiguity in the Evidence Theory”

In a recent paper, a functional AM (ambiguity measure) is introduced and an attempt is made to show that this functional qualifies as a measure of total aggregated uncertainty in the Dempster-Shafer theory. We show that this attempt fails due to a particular error in the proof of one of the principal theorems in the paper. Some additional remarks are made regarding recent research pertaining to the subject of the discussed paper.     

Information retrieval expert system “matchmaker”

This paper describes the information system used to search for a potential matrimonial partner. The search is based on comparison of the subject's record, which consists of his/her answers to about 400 items of a specially designed questionnaire, to the records of the potential partners. The basic principle of the system is representation of the set of candidates for the client with psychological warnings about potential “conflict zones” in relationships between client and candidate rather than a ranking of candidates based on hypothetical “psychological compatibility” indices.     

Comment and Further Result on “Fault Detection and Isolation Method Based on H−/H∞ Unknown Input Observer Design in Finite Frequency Domain”

This paper considers the work entitled “Fault detection and isolation method based on H_?/H_∞ unknown input observer design in finite frequency domain”, published previously in the Asian Journal of Control. We point out that some design matrices in the above mentioned article have no effect on the design result. Furthermore, we show that the conditions proposed therein for H_∞ design are conservative and propose an improved design method.     

Alias types for “environment-aware” computations

In previous work with Bono we introduced a calculus for modelling “environment-aware” computations, that is computations that adapt their behavior according to the capabilities of the environment. The calculus is an imperative, object-based language (with extensible objects and primitives for discriminating the presence or absence of attributes of objects) equipped with a small-step operational semantics.In this paper we define a type and effect system for the calculus. The typing judgements specify, via constraints, the shape of environments which guarantees the correct execution of expressions and the typing rules track the effect of expression evaluation on the environment. The type and effect system is sound w.r.t. the operational semantics of the language.     

Creative discovery in the lexical “validation gap”

Compound terms play a surprisingly key role in the organization of lexical ontologies. However, their inclusion forces one to address the issues of completeness and consistency that naturally arise from this organizational role. In this paper, we show how creative exploration in the space of literal compounds can reveal not only additional compound terms to systematically balance an ontology, but can also discover new and potentially innovative concepts in their own right.     

“Paraprogramming” manufacturing information systems

Computer integrated manufacturing (CIM) is creating unexpected problems for a growing number of manufacturing companies. Manufacturers are finding it especially difficult to attract programmers who are both willing and able to develop the highly complex software that integrates existing accounting, sales, production, engineering, and quality control information subsystems. Consequently, many companies abdicate their responsibility for manufacturing information systems and seek third party support ranging from consulting assistance to a total takeover of the company's information resources and operations. Companies that “give away” their internal information system capabilities to third parties will ultimately lose control of their enterprise information, a danger to be avoided. Off-the-shelf software for desktop computers has become sufficiently powerful to help solve a major portion of this serious problem. We hypothesize that manufacturing engineers (and others) can be trained to use packaged software to leverage their company's systems programming capabilities. In effect they would become “paraprogrammers” who would help design, develop, and maintain manufacturing information systems. This new type of professional would not require a computer science or similar educational background, but could be trained to satisfy many specialized programming needs in a manner similar to how paramedics and paralegals are trained and used in the medical and legal professions, respectively. This paper reports on the early stages of research to determine whether or not product design engineers can use a desktop relational database management system and its various command languages to develop a master bill of material information system (BOMIS). The purpose of the research is to evaluate the amount of programming complexity reduction and increased operational effectiveness that can be achieved through paraprogramming by manufacturing engineers.     

A model for “crisp reasoning” with fuzzy sets

In the setting of a general type of fuzzy algebras, this paper deals with a new theoretic view on the commonsense reasoning, consisting of a kind of Popper's search for conjectures and refutations. It is supposed that the reasoning is done in natural language, but only with nonambiguous precise and imprecise terms, respectively, represented by crisp and fuzzy sets. © 2012 Wiley Periodicals, Inc.     

Construction of a hermite rational “Wachspress type” finite element

This paper concerns the construction of a quadrilateral finite element whose interpolation space admits of rational fractions for basis functions of “Wachspress type” [1, 2]. The construction of this finite element, which is in a way the “rational” equivalent of the ADINI finite element[3, 4], is founded on a method analogous to the one used for Serendip degree-two finite element construction in[2]. The study of interpolation error is dealt with in a paper by Apprato, Arcangeli and Gout in this journal “Rational interpolation of Wachspress error estimates”.     

Further Comment on “Optimal Fuzzy Controller Design: Local Concept Approach”

Stability analysis and optimality are important in any systems. In the paper, "optimal fuzzy controller design: local concept approach," optimal fuzzy controller is design for Takagi-Sugeno fuzzy model. Unfortunately, it seems that some errors are happen and no simple correction can be done. In this paper, we show that some errors exit in the aforementioned paper with simple and clear examples.     

Comments on “Backpropagation Algorithms for a Broad Class of Dynamic Networks”

In a recent paper, De JesÚs proposed a general framework for describing dynamic neural networks. Gradient and Jacobian calculations were discussed based on backpropagation-through-time (BPTT) algorithm and real-time recurrent learning (RTRL). Some errors in the paper of De JesÚs bring difficulties for other researchers who want to implement the algorithms. This comments paper shows the critical parts of the publication and gives errata to facilitate understanding and implementation.