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This issue contains abstracts and critical comments on 11 articles, plus an editorial comment entitled "A Teacher Shortage?". Studies included concern solution processes on addition and subtraction examples; numerical rule induction; individual differences in performance on manipulative, pictorial, and symbolic tasks; the effect of a calculator curriculum; proportionality rules in judgments of area; van Hiele levels of geometric thought; interaction patterns and attitudes; word problems with ratios; incremental development in algebra; instruction with two types of calculators; and errors in translation from sentence to equation. Research studies reported in "Resources in Education" from July to September 1983 are listed. (MNS)

The habit of talking and thinking with the support of some device is always connected both with positive and dangerous aspects. My attempt is to discuss the meaning and the utility that didactic strategies using multimedial and digital devices could acquire in order to contribute to elaborate new cultural tools that are necessary to tackle the evolution of the social system that we are experiencing. Lipman and Piaget are compared. The notion of epistemic injustice is employed to analyze the relation between communicative patterns in young and adult people today. [ABSTRACT FROM AUTHOR]

A method for inducing knowledge by abstraction from a sequence of training examples is described. The proposed method, interference matching, induces abstractions by finding relational properties common to two or more exemplars. Three tasks solved by a program that uses an interference-matching algorithm are presented Several problems concerning the description of the training examples and the adequacy of interference matching are discussed, and directions for future research are considered. [ABSTRACT FROM AUTHOR]

Our original article provided a relatively detailed summary of Harold Jeffreys’s philosophy on statistical hypothesis testing. In response, Robert (2016) maintains that Bayes factors have a number of serious shortcomings. These shortcomings, Robert argues, may be addressed by an alternative approach that conceptualizes model selection as parameter estimation in a mixture model. In a second comment, Chandramouli and Shiffrin (2016) seek to extend Jeffreys’s framework by also taking into consideration data distributions that do not originate from either of the models under test. In this rejoinder we argue that Robert’s (2016) alternative view on testing has more in common with Jeffreys’s Bayes factor than he suggests, as they share the same “shortcomings”. On the other hand, we show that the proposition of Chandramouli and Shiffrin (2016) to extend the Bayes factor is in fact further removed from Jeffreys’s view on testing than the authors suggest. By elaborating on these points, we hope to clarify our case for Jeffreys’s Bayes factors. [ABSTRACT FROM AUTHOR]

The nature of concept learning is a core question in cognitive science. Theories must account for the relative difficulty of acquiring different concepts by supervised learners. For a canonical set of six category types, two distinct orderings of classification difficulty have been found. One ordering, which we call paradigm-specific, occurs when adult human learners classify objects with easily distinguishable characteristics such as size, shape, and shading. The general order occurs in all other known cases: when adult humans classify objects with characteristics that are not readily distinguished (e.g., brightness, saturation, hue); for children and monkeys; and when categorization difficulty is extrapolated from errors in identification learning. The paradigm-specific order was found to be predictable mathematically by measuring the logical complexity of tasks, i.e., how concisely the solution can be represented by logical rules. However, logical complexity explains only the paradigm-specific order but not the general order. Here we propose a new difficulty measurement, information complexity, that calculates the amount of uncertainty remaining when a subset of the dimensions are specified. This measurement is based on Shannon entropy. We show that, when the metric extracts minimal uncertainties, this new measurement predicts the paradigm-specific order for the canonical six category types, and when the metric extracts average uncertainties, this new measurement predicts the general order. Moreover, for learning category types beyond the canonical six, we find that the minimal-uncertainty formulation correctly predicts the paradigm-specific order as well or better than existing metrics (Boolean complexity and GIST) in most cases. [ABSTRACT FROM AUTHOR]

Highlights: [•] Understanding the evolution of the structure is very important in the oblique detonation propulsion design. [•] Three kinds of shock configurations at the end of the induction zone are observed and studied. [•] For the first time, it is found out that there is one critical Ma corresponding the maximum induction zone length. [•] Different mechanisms deciding the induction zone are analyzed. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to propose a transmission line model for induction machines, which serves to compute the common mode input impedance in the frequency range 10 Hz-1 MHz. Design/methodology/approach – Special diligence is attributed to the modelling of eddy currents inside the core lamination. In order to determine the transmission line parameters accurately, two modelling approaches are compared. The first is a two-dimensional simulation approach where iron core lamination effects are included by means of an equivalent material approximation. The second approach consists in fully three-dimensional analysis taking into account explicitly the eddy currents induced in the laminations. Findings – It is shown that homogenised equivalent material models may lead to large errors in the calculation of machine inductances, especially at high frequencies. However, the common mode input impedance, which is the final parameter of interest, seems to be less affected by the lamination modelling. Originality/value – The paper compares different analytical and numerical approaches in the frequency range 10 Hz-1 MHz and tries to give benchmarks for errors which occur due to a number of commonly used model simplifications. [ABSTRACT FROM AUTHOR]

The article presents an interview with Honda expert and Advanced Engine Management (AEM) cofounder, John Concialdi. He talks about his first experience with Honda because of his employee who have an Honda Integra car. He mentions on his unorthodox tuning philosophies in past days. He states on his interest in engines and electronic and mention that racer Jackie Stewart was a big hero of him in Formula racing.

We developed a novel small-volume (24-L) conical-shaped isoflurane anesthesia induction chamber for use in a den chamber and tested it along with 3 conventional stand-alone induction chambers (2 clear acrylic plastic chambers and a cylindrical-shaped chamber) to determine utility for daily short-duration manipulations of captive raccoons ( Procyon lotor). Although the conventional chambers were valuable, the majority of inductions were performed using the cone chamber in a pen setting. With the novel device, we were able to minimize the need for pre-anesthetic handling of animals and eliminate the need for injectable anesthesia agents. As a result, side effects normally associated with injectable agents were avoided. Mean anesthesia induction time using the cone chamber was 3.4 min (SD = 0.90). When used as designed, conventional chambers worked well, with induction times ranging from 2.7 min to 5.4 min. Because the stand-alone chambers were not reliant upon den chambers for use, they may provide greater utility for field work. The conical-shaped induction chamber, however, provides an option for safe short-duration anesthetization of captive raccoons and could perhaps be used with other species and in other research settings. Published 2012. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Abstract: We construct alternative frames of discernment from input belief functions. We assume that the core of each belief function is a subset of a so far unconstructed frame of discernment. The alternative frames are constructed as different cross products of unions of different cores. With the frames constructed the belief functions are combined for each alternative frame. The appropriateness of each frame is evaluated in two ways: (i) we measure the aggregated uncertainty (an entropy measure) of the combined belief functions for that frame to find if the belief functions are interacting in interesting ways, (ii) we measure the conflict in Dempster’s rule when combining the belief functions to make sure they do not exhibit too much internal conflict. A small frame typically yields a small aggregated uncertainty but a large conflict, and vice versa. The most appropriate frame of discernment is that which minimizes a probabilistic sum of the conflict and a normalized aggregated uncertainty of all combined belief functions for that frame of discernment. [Copyright &y& Elsevier]

Purpose – The purpose of the paper is to investigate the performance of induction machines with fractional-slot concentrated-windings. Design/methodology/approach – This paper examines induction machine performance with fractional-slot concentrated windings using the standard distributed lap windings as reference. Four designs are compared and various performance tradeoffs highlighted. The first machine has integral-slot distributed 2 slots/pole/phase lap winding and it serves as the reference winding. The second machine has a double-layer 1/2 slot/pole/phase winding, a workhorse for brushless DC machines. The third machine has double-layer 2/5 slot/pole/phase winding. Lastly, the fourth machine has single-layer 2/5 slot/pole/phase windings. The comparison includes torque-speed curves (including the effects of major space harmonic components), rotor bar losses, and ripple torque levels. Findings – Based on the analysis results presented here, the traditional distributed lap winding is proven to be superior to FSCW in terms of torque production and rotor bar losses for induction machine applications. The 1/2 spp shows some promising results in terms of torque production, in addition to significant reduction and simplification of end turns with lower number of coils albeit with more turns/coil (12 slots vs 48 slots). The penalty is the additional rotor bar losses due to the 2nd and 4th harmonic mmf components. The 2/5 spp is not promising for torque production and should be avoided. The transient simulation results that simultaneously take into account the effects of all space harmonics and magnetic saturation showed comparable trends compared to the harmonic analysis results. It has also been shown that FSCW tend to have higher torque ripple compared to distributed windings. Originality/value – To the best of the authors' knowledge, this paper for the first time attempts to quantitatively address the tradeoffs involved in using FSCW in induction machines. [ABSTRACT FROM AUTHOR]

The management implications (MI) section of articles in The Journal of Wildlife Management ( JWM) and Wildlife Society Bulletin ( WSB) is meant to relay transparent, applicable information from researchers to managers. I questioned whether this goal was being met because inspection of paper titles in these journals showed many studies do not address management topics. Accordingly, I developed a classification scheme for statements in the MI section and analyzed the nature and content of randomly selected MI sections ( n = 80) in Volume 72 (2008) of JWM. Management implications (deductions or inductions) made up 5.5 ± 1% standard error of statements in the sample ( n = 562 statements). Accordingly, >90% of the statements in the sample of MI sections were not MIs. The MI heading does not inform readers of section content. I recommend a more flexible heading (e.g., Implications, Research Needs, Recommendations, Conclusions) or elimination of the section because salient material usually appears in other sections of a paper anyway. © 2011 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to continue studies previously reported with the primary focus of optimizing an inductor design. The potential benefits of hyperthermia for cancer therapy, particularly metastatic cancers of the prostate, may be realized by the use of targeted magnetic nanoparticles that are heated by alternating magnetic fields (AMFs). Design/methodology/approach – To further explore the potential of this technology, a high-throughput cell culture treatment system is needed. The AMF requirements for this research present challenges to the design and manufacture of an induction system because a high flux density field at high frequency must be created in a relatively large volume. Additional challenges are presented by the requirement that the inductor must maintain an operating temperature between 35 and 39°C with continuous duty operation for 1 h or longer. Results of simulation and design of two devices for culture samples and for in vitro tests of multiple samples in uniform field are described. Findings – The inductor design chosen provides a uniform distribution of relatively high magnetic field strength while providing an optimal reduction in the voltage and power requirement. Through development of design and selection of magnetic concentrator, the exposure of the cell cultures to the heat generated by the inductor is minimized. Originality/value – This method of generating uniform high AC magnetic fields in a large volume is beneficial for the study of hyperthermia in cells for a high throughput, necessary for cancer treatment research. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to study an electromagnetic (EM) wiping process based on the EM brake (EMB) principle for hot-dip galvanizing lines. This EMB system must act complementary to a classical air wiping system for higher drag out velocities for which the only air wiping system is no more sufficient. Design/methodology/approach – At first, the basic phenomena of the braking of a liquid driven by an upcoming strip thanks to a DC magnetic field are analyzed with a simplified analytical model. This model shows the influence of different relevant parameters such as the magnetic field intensity or the strip upcoming velocity. Then, a 2D numeric finite elements model coupling the EMs, the fluid mechanics and a deformed mesh technique is set up and shows clearly the braking effect on the liquid zinc. At last, some first results of a 3D extension of the former 2D model are shown, mainly concerning the end effects on the edge of the strip. This EM wipe effect has been experimentally demonstrated in a prototype hot-dip galvanizing line. Findings – The paper shows the possibility of controlling the thickness of a liquid zinc layer thanks to a DC magnetic field produced by high-intensity permanent magnets. Originality/value – Such an innovative way of wiping liquid zinc thanks to a DC magnetic field is able to wipe liquid zinc excess and control the liquid layer thickness with a low electric losses level. This is a major advantage compared with other known wiping techniques such as high-frequency pin-shaped inductors which may imply an overheating of the liquid zinc. [ABSTRACT FROM AUTHOR]

Abstract: Data mining research has been drawing a lot of interest and attention from various fields since late 1980s. The rapid progress has been achieved from three aspects: the prosperity of data mining conferences, the significant number of data mining algorithms, and widely applied areas of data mining techniques. With the continuing growth of the data volumes in many domains, the need of employing data mining techniques provides not only new opportunities but also immense challenges. In this article, we present our study on a challenging topic – integrating induction and deduction for noisy data mining. In particular, we assume the mechanism that corrupts the input data is a set of structured knowledge in the form of Associative Corruption (AC) rules. We apply deductive reasoning to generate the noise corruption rules; make error corrections on the input data with the help of these rules; and perform inductive learning from the corrected input data. Our experimental results show that the proposed integration framework is effective. [Copyright &y& Elsevier]

Abstract: The inverse of the nonparametric information operator is key for finding doubly robust estimators and the semiparametric efficient estimator in missing data problems. It is known that no closed-form expression for the inverse of the nonparametric information operator exists when missing data form nonmonotone patterns. The Neumann series is usually used for approximating the inverse. However, the Neumann series approximation is only known to converge in norm, which is not sufficient for establishing statistical properties of the estimators yielded from the approximation. In this work, we show that convergence of the Neumann series approximations to the inverse of the nonparametric information operator and to the efficient scores in missing data problems can be obtained under very simple conditions. This paves the way to a study of the asymptotic properties of the doubly robust estimators and the locally semiparametric efficient estimator in those difficult situations. [Copyright &y& Elsevier]

Abstract: In this paper, we propose a granularity-based framework of deduction, induction, and abduction using variable precision rough set models proposed by Ziarko and measure-based semantics for modal logic proposed by Murai et al. The proposed framework is based on -level fuzzy measure models on the basis of background knowledge, as described in the paper. In the proposed framework, deduction, induction, and abduction are characterized as reasoning processes based on typical situations about the facts and rules used in these processes. Using variable precision rough set models, we consider -lower approximation of truth sets of nonmodal sentences as typical situations of the given facts and rules, instead of the truth sets of the sentences as correct representations of the facts and rules. Moreover, we represent deduction, induction, and abduction as relationships between typical situations. [Copyright &y& Elsevier]

The article discusses a study about the effectiveness of mentoring programs in the induction of new music educators. The literature found that most mentoring programs, although beneficial for general classroom teachers, are often perceived as ineffective by new music educators. Without the guidance of mentoring programs that address these concerns, many new music educators may fall prey to frustration, burnout, and attrition. In conclusion, the mentoring of new music teachers is an area that must be further addressed by the educational community as a whole.

Abstract: We examine parallel algorithms for molecular dynamics simulations involving long-range induction interactions. The algorithms are tested by performing molecular dynamics simulations of water with an intermolecular potential that explicitly includes contributions from pair, three-body and induction interactions. Both cyclic and balanced force decomposition methods are implemented to decompose the parallelizable components of induction, pair and three-body interactions using a message passing interface. We report that more than 90% of the induction calculation, and 98% of the total calculation can be effectively parallelized. A reasonably good speedup of 15.7 times and an efficiency of 49.1% are obtained on 32 processors with the balance force decomposition algorithm. [Copyright &y& Elsevier]

Purpose – This paper aims to discuss a comprehensive analysis of the effects of torque and flux hysteresis bands on the inverter average switching frequency considering an induction machine drive under the control of the Takahashi DTC strategy. Design/methodology/approach – The analysis of the effects of torque and flux hysteresis bands on the inverter average switching frequency is carried out taking into account the speed range and the sampling period. Findings – It has been found that the inverter average switching frequency could be more or less taken down according to the speed range and the sampling period by selecting suitable flux and torque hysteresis bands. Research limitations/implications – This work should be extended by an experimental validation of the established results. Practical implications – The reduction of the inverter switching frequency is of great importance in direct torque controlled induction motor drive as far as it leads to a decrease of the torque ripple and an increase of the efficiency. Originality/value – For given torque and flux hysteresis bands, the inverter average switching frequency presents nonlinear shape. Given the fact that the flux switching frequency is a linear function of the speed, one can conclude that the nonlinearity of the inverter average switching frequency is due to the torque switching frequency. This statement has been proven by the introduction of the so-called focal speeds for the torque switching frequency turns to be null. [ABSTRACT FROM AUTHOR]

Purpose – This paper seeks to discuss the implementation of the rotor flux oriented control (RFOC) in a four-switch three-phase inverter (FSTPI)-fed induction motor drive. Design/methodology/approach – The implementation is achieved considering a current regulation of the FSTPI. Such a regulation is done thanks to bang-bang regulators. As far as the FSTPI is fed by a battery pack, the paper considers an electrical equivalent circuit of such a power supply. Findings – Simulation works, carried out considering the case of an ideal model of the battery pack and the case where the electrical equivalent circuit of the battery pack is taken into account, have shown that the drive dynamic performance are practically the same. Furthermore, and in order to highlight the performance of the induction motor fed by a FSTPI, these are compared with those obtained with the induction motor fed by a conventional six-switch three-phase inverter (SSTPI), considering both models of the battery pack. It has been found that the drive offers almost the same dynamic and steady-state performance. Research limitations/implications – The work should be extended by an experimental validation of the simulation results. Practical implications – The established results open up crucial benefits from the point of view of cost-effectiveness and volume-compactness improvements of induction motor drives especially in large-scale industries such as the automotive one where electric and hybrid propulsion systems are currently regarded as an interesting alternative to substitute or to assist the thermal propulsion systems. Originality/value – The implementation of the RFOC in FSTPI-fed induction motor drives is feasible and exhibits almost the same performance as those obtained by conventional SSTPI-fed induction motor drives under the same control strategies. [ABSTRACT FROM AUTHOR]

Purpose – The paper aims to discuss the comparison of the performance of four space-vector pulse-width modulation (SVPWM) strategies dedicated to four-switch three-phase inverters (FSTPI). Design/methodology/approach – The comparison is based on three comparison criteria: the total harmonic distortion, the switching loss factor, and the quality factor. The comparison is extended to the FFT of the phase currents and to the analysis of the ripples of the electromagnetic torque of the induction motor. Findings – It has been clearly shown that the basic SVPWM strategy of the conventional six-switch three-phase inverter (SSTPI) offers better performance than those of the four FSTPI-SVPWM strategies. This said, it has been found that the performance of two among the four FSTPI-SVPWM strategies tend to those of the SSTPI-SVPWM basic strategy, especially in high switching frequencies. Research limitations/implications – The work should be extended by an experimental validation of the simulation results. Practical implications – The established results open up crucial benefits from the point of view of cost-effectiveness and volume-compactness improvements of induction motor drives especially in large-scale industries such as the automotive one where electric and hybrid propulsion systems are currently regarded as an interesting alternative to substitute or to assist the thermal propulsion systems. Originality/value – The implementation in the FSTPI feeding an induction motor of SVPWM strategies exhibiting acceptable performance, which tend to those yielded by the SSTPI-SVPWM basic strategy especially in high switching frequencies, is extended here. [ABSTRACT FROM AUTHOR]

Abstract: An important element of learning from examples is the extraction of patterns and regularities from data. This paper investigates the structure of patterns in data defined over discrete features, i.e. features with two or more qualitatively distinct values. Any such pattern can be algebraically decomposed into a spectrum of component patterns, each of which is a simpler or more atomic “regularity.” Each component regularity involves a certain number of features, referred to as its degree. Regularities of lower degree represent simpler or more coarse patterns in the original pattern, while regularities of higher degree represent finer or more idiosyncratic patterns. The full spectral breakdown of a pattern into component regularities of minimal degree, referred to as its power series, expresses the original pattern in terms of the regular rules or patterns it obeys, amounting to a kind of “theory” of the pattern. The number of regularities at various degrees necessary to represent the pattern is tabulated in its power spectrum, which expresses how much of a pattern''s structure can be explained by regularities of various levels of complexity. A weighted mean of the pattern''s spectral power gives a useful numeric summary of its overall complexity, called its algebraic complexity. The basic theory of algebraic decomposition is extended in several ways, including algebraic accounts of the typicality of individual objects within concepts, and estimation of the power series from noisy data. Finally some relations between these algebraic quantities and empirical data are discussed. [Copyright &y& Elsevier]

The cytochrome P450 (P450 or CYP) monooxygenases, CYP2D6, CYP2C19 and CYP2C9, display polymorphism. CYP2D6 and CYP2C19 have been studied extensively and, despite their low abundance in the liver, they have been found to catalyze the metabolism of many drugs. CYP2D6 has many allelic variants, whereas CYP2C19 has only seven. Most variants are translated into inactive, truncated proteins or fail to express any protein. There is, as yet, no clear information about the other CYPs (CYP1A1, CYP2A6, CYP2B6, CYP2E1 and CYP3A4/5) polymorphism. When two drugs that are substrates of a polymorphic CYP enzyme are administered concomitantly during drug therapy, each will compete for that enzyme and competitively inhibit the metabolism of the other. This can result in toxicity. Patients who are poor metabolizers (PMs), extensive metabolizers (EMs), and ultrarapid metabolizers (URMs) can be identified. Having such information will help in determining the appropriate dosage of certain drugs when treating patients with an inherited abnormality of a drug-metabolizing enzyme. The pharmacokinetics of many drugs often exhibit considerable inter-individual variability, largely because of variations in the expression of different CYP enzymes in the liver and other tissues. Relatively selective in vivo substrate probes have been discovered for several major CYP isoforms involved in oxidative drug metabolism. In view of the remarkable progress in this particular field, it is to be expected that more genetic polymorphisms will be reported with the discovery of more and more new drugs in the near future. [ABSTRACT FROM AUTHOR]

The U.S. Department of Defense (DoD) has been utilizing polymer matrix composite (PMC) and structural adhesive materials in military equipment for over 20 years. However, the volume of PMCs in fielded systems has remained relatively low. Currently, however, the DoD has established strategic goals that will necessitate the use of lightweight composites in order to meet performance requirements. Therefore, the volume of composites used in DoD systems is expected to see an unprecedented 100-fold increase over the next 30 years. As production volumes increase, the need to address environmental impact increases. The major contributions to environmental degradation from composites are generation of hazardous air pollutants (HAPs) and generation of hazardous (HW) and solid wastes. HAPs result primarily during the curing of the composite. HWs arise from expiration of stockpiled resin materials and from soiled support media used during manufacturing and clean up. Due to the wide range of applications and materials systems, as well as manufacturing and repair requirements, a family of environmentally benign solutions is needed to reduce and eliminate environmental impacts from PMC manufacturing. Solutions are proposed involving use of new technologies and materials to reduce pollutants from composite manufacturing. The technologies proposed include alternative curing of thermoset composites using electron beam (E-beam) irradiation and materials substitution employing thermoplastics processed using electromagnetic irradiation. [ABSTRACT FROM AUTHOR]