Large classes

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Student engagement and group work are critical to developing competencies, deeper learning, and attributes that align with 21st-century skills. In an increasingly competitive and dynamic workforce, the ability for employees to engage in collaborative workgroups is essential. A new capstone group-work assignment using Online Human Touch (OHT) strategies was integrated into an Information Systems course at a regional university in the Caribbean. The course typically enrolls 250-300+ students per semester with one instructor. The assignment simulated a real-world business 'eMeeting' to proactively increase student engagement and retention. This action research study collected quantitative and qualitative data three years prior to and three years after the integration of the new 'eMeeting' group-work assignment. Quantitative data showed improved academic performance, higher scores on the standardized final exam, and decreases in attrition while qualitative data showed significant increases in student engagement. Integrating the 'eMeeting' assignment into the large online course provided students with the opportunity to apply the knowledge, skills, and experience gained throughout the semester. It also enhanced key soft skills sought by employers including problem-solving, ability to work in teams, communication, leadership, and time management.

Computer vision systems attempt to recover useful information about the three-dimensional world from huge image arrays of sensed values. Since direct interpretation of large amounts of raw data by computer is difficult, it is often convenient to partition (segment) image arrays into low-level entities (groups of pixels with similar properties) that can be compared to higher-level entities derived from representations of world knowledge. Solving the segmentation problem requires a mechanism for partitioning the image array into low-level entities based on a model of the underlying image structure. Using a piecewise-smooth surface model for image data that possesses surface coherence properties, we have developed an algorithm that simultaneously segments a large class of images into regions of arbitrary shape and approximates image data with bivariate functions so that it is possible to compute a complete, noiseless image reconstruction based on the extracted functions and regions. Surface curvature sign labeling provides an initial coarse image segmentation, which is refined by an iterative region growing method based on variable-order surface fitting. Experimental results show the algorithm's performance on six range images and three intensity images.

Background and Objectives: Autofluorescence spectroscopy is a promising tool for oral cancer detection. Its reliability might be improved by using a reference database of spectra from healthy mucosa. We investigated the influence of anatomical location on healthy mucosa autofluorescence. Study Design/Materials and Methods: Spectra were recorded from 97 volunteers using seven excitation wavelengths (350-450 nm), 455-867 nm emission. We studied intensity and applied principal component analysis (PCA) with classification algorithms. Class overlap estimates were calculated. Results: We observed differences in fluorescence intensity between locations. These were significant but small compared to standard deviations (SD). Normalized spectra looked similar for locations, except for the dorsal side of the tongue (DST) and the vermilion border (VB). Porphyrinlike fluorescence was observed frequently, especially at DST. PCA and classification confirmed VB and DST to be spectrally distinct. The remaining locations showed large class overlaps. Conclusions: No relevant systematic spectral differences have been observed between most locations, allowing the use of one large reference database. For DST and VB separate databases are required.

Part I of this paper (Adjiman et al., 1997) described the theoretical foundations of a global optimization algorithm, the BB algorithm, which can be used to solve problems belonging to the broad class of twice-di erentiable NPLs. For any such problem, the ability to automatically generate progressively tighter convex lower bounding problems at each iteration guarantees the convergence of the branchand-bound BB algorithm to within of the global optimum solution. Several methods were presented for the construction of convex valid underestimators for general nonconvex functions. In this second part, the performance of the proposed algorithm and its alternative underestimators is studied through their application to a variety of problems. An implementation of the BB is described and a number of rules for branching variable selection and variable bound updates are shown to enhance convergence rates. A user-friendly parser facilitates problem input and provides exibility in the selection of an underestimating strategy. In addition, the package features both automatic di erentiation and interval arithmetic capabilities. Making use of all the available options, the BB algorithm successfully identi es the global optimum solution of small literature problems, of small and medium size chemical engineering problems in the areas of reactor network design, heat exchanger network design, reactor-separator network design, of generalized geometric programming problems for design and control, and of batch process design problems with uncertainty.

We investigate metric properties of the polynomial digits occurring in a large class of Oppenheim expansions of Laurent series, including Lüroth, Engel, and Sylvester expansions of Laurent series and Cantor infinite products of Laurent series. The obtained results cover those for special cases of Lüroth and Engel expansions obtained by Grabner, A. Knopfmacher, and J. Knopfmacher. Our results applied in the cases of Sylvester expansions and Cantor infinite products are original. We also calculate the Hausdorff dimensions of different exceptional sets on which the above-mentioned metric properties fail to hold.

This work presents an approximate solution method for the inÿnite-time nonlinear quadratic optimal control problem. The method is applicable to a large class of nonlinear systems and involves solving a Riccati equation and a series of algebraic equations. The conditions for uniqueness and stability of the resulting feedback policy are established. It is shown that the proposed approximation method is useful in determining the region in which the constrained and unconstrained optimal control problems are identical. A reactor control problem is used to illustrate the method.

Outliers in financial data can lead to model parameter estimation biases, invalid inferences and poor volatility forecasts. Therefore, their detection and correction should be taken seriously when modeling financial data. This paper focuses on these issues and proposes a general detection and correction method based on wavelets that can be applied to a large class of volatility models. The effectiveness of our proposal is tested by an intensive Monte Carlo study for six well known volatility models and compared to alternative proposals in the literature, before applying it to three daily stock market indexes. The Monte Carlo experiments show that our method is both very effective in detecting isolated outliers and outlier patches and much more reliable than other wavelet-based procedures since it detects a significant smaller number of false outliers.

We address the issue of the relation between local quantities and the uncertainty principle. We approach the problem by defining local quantities as conditional standard deviations, and we relate these to the uncertainty product appearing in the standard uncertainty principle. We show that the uncertainty product for the average local standard deviations is always less than or equal to the standard uncertainty product and that it can be arbitrarily small. We apply these results to the short-time Fourier transform/spectrogram to explore the commonly held notion that the uncertainty principle somehow limits local quantities. We show that, indeed, for the spectrogram, there is a lower bound on the local uncertainty product of the spectrogram due to the windowing operation of this method. This limitation is an inherent property of the spectrogram and is not a property of the signal or a fundamental limit. We also examine the local uncertainty product for a large class of time-frequency distributions that satisfy the usual uncertainty principle, including the Wigner distribution, the Choi-Williams distribution, and many other commonly used distributions. We obtain an expression for the local uncertainty product in terms of the signal and show that for these distributions, the local uncertainty product is less than that of the spectrogram and can be arbitrarily small. Extension of our approach to an entropy formulation of the uncertainty principle is also considered.

We present a rational version of the classical Landen transformation for elliptic integrals. This is employed to obtain explicit closed-form expressions for a large class of integrals of even rational functions and to develop an algorithm for numerical integration of these functions.

Research skills are important for any academic and can be of great benefit to any professional person. These skills are, however, difficult to teach and to learn. In the Department of Computer Science at the University of the Witwatersrand we have for a number of years included the completion of a research report as part of our Honours programme. This paper is a case study of how we have implemented an introductory research methods Honours course to increase our students' exposure to research and to help them cope better with the research reports. This course provides an effective way of introducing research to a relatively large class of Honours students. It is now being given for the second time.

We propose simple Felgln-Fuchs contour integral representations for the characters of a large class of rational conformal field theories These include the A, D and E series SU(2) WZW theories, the A and D series c < 1 mlmmal theories, and the k = 1 SU(N) WZW theories All these theories are characterized by the absence of the zeroes m the wronskaan determinant of the characters m the interior of moduh space Tins proposal is verified by several calculations

In this work we will discuss the solution of an initial value problem of parabolic type. The main objective is to propose an alternative method of solution, one not based on finite difference or finite element or spectral methods. The aim of the present paper is to investigate the application of the Adomian decomposition method for solving the Fokker-Planck equation and some similar equations. This method can successfully be applied to a large class of problems. The Adomian decomposition method needs less work in comparison with the traditional methods. This method decreases considerable volume of calculations. The decomposition procedure of Adomian will be obtained easily without linearizing the problem by implementing the decomposition method rather than the standard methods for the exact solutions. In this approach the solution is found in the form of a convergent series with easily computed components. In this work we are concerned with the application of the decomposition method for the linear and nonlinear Fokker-Planck equation. To give overview of methodology, we have presented several examples in one and two dimensional cases.

Conservation of information (COI) popularized by the no free lunch theorem is a great leveler of search algorithms, showing that on average no search outperforms any other. Yet in practice some searches appear to outperform others. In consequence, some have questioned the significance of COI to the performance of search algorithms. An underlying foundation of COI is Bernoulli's Principle of Insufficient Reason 1 (PrOIR) which imposes of a uniform distribution on a search space in the absence of all prior knowledge about the search target or the search space structure. The assumption is conserved under mapping. If the probability of finding a target in a search space is p, then the problem of finding the target in any subset of the search space is p. More generally, all some-to-many mappings of a uniform search space result in a new search space where the chance of doing better than p is 50-50. Consequently the chance of doing worse is 50-50. This result can be viewed as a confirming property of COI. To properly assess the significance of the COI for search, one must completely identify the precise sources of information that affect search performance. This discussion leads to resolution of the seeming conflict between COI and the observation that some search algorithms perform well on a large class of problems.

In a university setting, there is a great diversity in terms of socio-cultural, political, religious and racial backgrounds among students and lecturers. This diversity, with the presence of an appropriate lecturer-student relationship creates a campus environment that prepares students and lecturers to live and work amicably in a socio-culturally diverse society. It also equips them to respond to an increasing

A systematic density functional theory study supported by extended X-ray absorption fine structure (EXAFS) and infrared spectroscopic data was conducted to elucidate how structure and vibrational spectra of aqueous desferrioxamine B (DFOB) metal complexes vary with the metal ion identity. Structural parameters derived from EXAFS analyses and trends in metal binding constants are well reproduced and validated by the applied computational model. Vibrational mode analysis guides determination and recognition of crucial structureand metal-sensitive infrared marker bands. The key marker bands, CO and CN stretching modes, dominate the infrared spectra in the 1400-1650 cm −1 region. The modes are sensitive to the stability and size of the metal core (first coordination shell) and indicative of its deformation from the octahedral symmetry. The results shed light on the fundamental structural and electronic factors that control metal binding by siderophores, and drive their potentially rich and largely unexplored interactions with trace metals.

We consider a topological game G Π involving two players α and β and show that, for a paratopological group, the absence of a winning strategy for player β implies the group is a topological one. We provide a large class of topological spaces X for which the absence of a winning strategy for player β is equivalent to the requirement that X is a Baire space.

A large literature on teaching and learning heralds the benefits of discussion for student learner outcomes, especially its ability to improve students' critical thinking skills. Yet, there are few studies that compare the effects of different types of face-to-face discussions. Using student surveys, we analyze the benefits of small-group and large-class discussions in an upper-level political theory course. We also analyze whether the same types of students are likely to participate, and reap the benefits of, both types of discussions. We find that overall, participation is higher in small-group discussions, as are students' perceptions of learner outcomes. We also find a more equal participation of students of different ethnic backgrounds in small-group discussions.

Especially during the first year in university absenteeism can have detrimental effects on grades, and social integration of the student in the university community. According to pedagogical literature altering teaching methods from lecturing toward engaging teaching, which applies various active teaching methods in the university classroom, can enhance learning, student participation, decrease absenteeism, and improve critical thinking and problem solving skills. In this research study, I used active learning and engaging teaching to prevent absenteeism in an attempt to improve grades, and to enhance interest in Biology among students in large first year Introductory Biology classes. Results show that students were less absent from the class that used engaging teaching methods (Engaging Class) compared to classes that were taught by traditional lecturing without class engagement (Lecture Class). Also, the concept inventory test showed a significant increase in post-test quiz grades in the Engaging Class compared to the Lecture Class at the end of the semester. The student CLASSE survey indicated more interaction between faculty and students in the section that was taught using engaging methods. According to student focus group interviews, students in the Engaging class appreciated the class activities and reported benefits for learning.

Temperature warnings are important forecasts because they are used to protect life and property. Temperature forecasting is the application of science and technology to predict the state of the temperature for a future time and a given location. Temperature forecasts are made by collecting quantitative data about the current state of the atmosphere. In this paper, a neural network-based algorithm

Diagnosis and prognosis are processes of assessment of a system's health -past, present and future -based on observed data and available knowledge about the system. Due to the nature of the observed data and the available knowledge, the diagnostic and prognostic methods are often a combination of statistical inference and machine learning methods. The development (or selection) of appropriate methods requires appropriate formulation of the learning and inference problems that support the goals of diagnosis and prognosis. An important aspect of the formulation is modeling -relating the real system to its mathematical abstraction. This paper explores the impact of diagnostic and prognostic goals on modeling and reasoning system requirements, with the purpose of developing a common software framework that can be applied to a large class of systems. In particular, the role of failure-dependency modeling in the overall decision problem is discussed. The applicability of Qualtech Systems' modeling and diagnostic software tools to the presented framework for both the development and implementation of diagnostics and prognostics is assessed. Finally, a potential application concept for advancing the reliability of Navy shipboard Condition Based Maintenance (CBM) systems and processes is discussed.

System-on-chip (SoC) is developing as a new paradigm in electronic system design. This allows an entire hardware/software system to be built on a single chip, using predesigned components. This paper examines the achievements and future of novel approach and flow for an efficient design of application-specific multiprocessor system-on-chip (called GAM-SoC). The approach is based on a generic architecture model which is used as a template throughout the design process. The key characteristics of this model are its great modularity, flexibility and scalability which make it reusable for a large class of applications. In the flow, architectural parameters are first extracted from a high-level system specification and then used to instantiate architectural components, such as processors, memory modules, IP-hardware blocks, and on-chip communication networks. The flow includes the generation of hardware/software wrappers that adapts the processor to the onchip communication network in an application-specific way. The feasibility and effectiveness of this approach are illustrated by significant demonstration examples. Index Terms-Component-based design, generic architecture model, systematic design methodology, on-chip communication wrappers, AHB-AMBA, multiprocessor SoC. I. INTRODUCTION o accommodate the ever increasing performance requirements of application domains such as xDSL technology, networking, wireless, game applications, multiprocessor SoCs are more and more required [34]. Often, the multiprocessor SoC architectures require for applicationspecific optimization heterogeneous processors (DSP, CPUs), signal processing hardware, hardware controllers, DRAMs, Flash Memories, high-performance on-chip communication interfaces, and sophisticated communication protocols [11].

This paper presents a general-purpose computer program which is capable of designing a large class of optimum (in the minimax sense) FIR linear phase digital filters. The program has options for designing such standard filters as lowpass, high-pass, bandpass, and bandstop filters, as well as multipassband-stopband filters, differentiators, and Hilbert transformers. The program can also be used to design filters which approximate arbitrary frequency specifications which are provided by the user. The program is written in Fortran, and is carefully documented both by comments and by detailed flowcharts. The filter design algorithm is shown to be exceedingly efficient, e.g., it is capable of designing a filter with a 100-point impulse response in about 20 s.

Polyhydroxyalkanoates (PHAs) comprise a large class of polyesters that are synthesized by many bacteria as an intracellular carbon and energy compound. Analysis of isolated PHAs reveal interesting properties such as biodegradability and biocompatibility. Research was focused only recently on the application of PHA in implants, scaffolds in tissue engineering, or as drug carriers. Such applications require that PHA be produced at a constant and reproducible quality. To date this can be achieved best through bacterial production in continuous culture where growth conditions are kept constant (chemostat). Recently, it was found that PHA producing bacteria are able to grow simultaneously limited by carbon and nitrogen substrates. Thus, it became possible to produce PHA at high yields on toxic substrate and also control its composition accurately (tailor-made synthesis). Finally, applications of PHA in medicine are discussed.

Discretized population balances of aggregating systems are known to consistently over-predict number densities for the largest particles. This over-prediction has been attributed recently by the authors (Kumar and Ramkrishna, 1996, Chem. Engng Sci.51, 1311–1332) to steeply non-linear gradients in the number density when a fixed pivotal particle size is used for each discrete interval. The present work formulates macroscopic balances of populations with due regard to the evolving non-uniformity of the size distribution in each size interval as a result of breakage and aggregation events. This is accomplished through a varying pivotal size for each interval adapting to the prevailing non-uniformity of the number density in the interval. The technique applies to a general grid and preserves any two arbitrarily chosen properties of the population. Comparisons of the numerical and analytical results have been made for pure aggregation for the constant, sum and product kernels. It is established that numerical predictions from macroscopic balances are significantly improved by an adapting pivot accounting for non-uniformities in the number density.

We investigate possible extensions of the susceptible-infective-removed (SIR) epidemic model. We show that there exists a large class of functions representing interaction between the susceptible and infective populations for which the model has a realistic behaviour and preserves the essential features of the classical SIR model. We also present a new discretisation of the SIR model which has the advantage of possessing a conserved quantity, thus making possible the estimation of the non-infected population at the end of the epidemic. A cellular automaton SIR is also constructed on the basis of the discrete-time system.

Many large lecture classes at undergraduate institutions have started to utilize technology to engage students. A mixed methods design was used in this dissertation research to build a comprehensive understanding of the statistical relationships among mathematics anxiety, math self-efficacy, and achievement in mathematics among students in a large lecture, undergraduate calculus class taught using clickers. The purpose of this study was to develop an understanding of the statistical relationships and of the students’ experiences and perspectives on the relationships among mathematics self-efficacy, math anxiety, and achievement, along with the effect of clicker use on these variables, with attention given to changes in student perceptions during the semester. Statistical analysis was conducted utilizing quantitative survey data, and qualitative methods were used to analyze student interview data. Pairwise statistical relationships identified in previous research were confirmed among math anxiety, mathematics self-efficacy, and achievement in mathematics. Findings also revealed the potential for clickers to help promote desired learning outcomes when used effectively by students and instructors. Future research on the effect of clicker use in other types of mathematics courses besides calculus, in classes with students representing a more diverse range of racial/ethnic backgrounds, and with smaller class sizes will help build on the knowledge gained from this study.

This chapter focuses on ways in which talk and culture mediate learning in large classes in China. We suggest reasons why classes are kept large and show how language teachers use pair and group work but seem to scaffold dialogue with the whole class. We argue that teaching large classes is successful in China partly because of interactive techniques in classroom dialogue, but mainly because of the underlying culture of learning. The Chinese culture of learning is elaborated using questionnaire data with both British and Chinese students and interviews with Chinese teachers. The dialogue about large classes needs to take cultures of learning into account and in the Chinese case to consider collectivist and Confucian values. Classroom events are illustrated using visual ethnography, particularly the stages in a largeclass language lesson in a primary school.

The structure of the kinematic and dynamic models of wheeled mobile robots is analyzed. It is shown that, for a large class of possible configurations, they can be classified into five types, characterized by generic structures of the model equations.

In this paper we discuss Augmented Reality (AR) displays in a general sense, within the context of a Reality-Virtuality (RV) continuum, encompassing a large class of "Mixed Reality" (MR) displays, which also includes Augmented Virtuality (AV). MR displays are defined by means of seven examples of existing display concepts in which real objects and virtual objects are juxtaposed. Essential factors which distinguish different Mixed Reality display systems from each other are presented, first by means of a table in which the nature of the underlying scene, how it is viewed, and the observer's reference to it are compared, and then by means of a three dimensional taxonomic framework, comprising: Extent of World Knowledge (EWK), Reproduction Fidelity (RF) and Extent of Presence Metaphor (EPM). A principal objective of the taxonomy is to clarify terminology issues and to provide a framework for classifying research across different disciplines.

We develop a theory of Schur functions in noncommuting variables, assuming commutation relations that are satisfied in many wellknown associative algebras. As an application of our theory, we prove Schur-positivity and obtain generalized Littlewood-Richardson and Murnaghan-Nakayama rules for a large class of symmetric functions, including stable Schubert and Grothendieck polynomials. © 1998 Published by Elsevier B.V.

We present rigorous local and global bifurcation results for a concrete example from 3-dimensional nonlinear elastostatics — the problem of barrelling of compressed cylindrical columns. We use standard tools of bifurcation theory for the local analysis, already producing results that are rare in our field. For the global part we employ the generalized degree designed by Healey and Simpson to overcome the specific difficulties of 3-dimensional nonlinear elasticity. Ours are the first global bifurcation results for a problem from 3-dimensional nonlinear elastostatics not governed by ordinary differential equations. Moreover, our approach to the barrelling problem provides a paradigm for the solution of a large class of problems in nonlinear elastostatics concerning bifurcation from a homogeneously deformed state.

We develop a new method to uniquely solve a large class of heat equations, so-called Kolmogorov equations in infinitely many variables. The equations are analyzed in spaces of sequentially weakly continuous functions weighted by proper (Lyapunov type) functions. This way for the first time the solutions are constructed everywhere without exceptional sets for equations with possibly nonlocally Lipschitz drifts. Apart from general analytic interest, the main motivation is to apply this to uniquely solve martingale problems in the sense of Stroock-Varadhan given by stochastic partial differential equations from hydrodynamics, such as the stochastic Navier-Stokes equations. In this paper this is done in the case of the stochastic generalized Burgers equation. Uniqueness is shown in the sense of Markov flows.

We construct and analyze a large class of exact five-and six-dimensional regular and static solutions of the vacuum Einstein equations. These solutions describe sequences of Kaluza-Klein bubbles and black holes, placed alternately so that the black holes are held apart by the bubbles. Asymptotically the solutions are Minkowski-space times a circle, i.e. Kaluza-Klein space, so they are part of the (µ, n) phase diagram introduced in hep-th/0309116. In particular, they occupy a hitherto unexplored region of the phase diagram, since their relative tension exceeds that of the uniform black string. The solutions contain bubbles and black holes of various topologies, including six-dimensional black holes with ring topology S 3 × S 1 and tuboid topology S 2 × S 1 × S 1 . The bubbles support the S 1 's of the horizons against gravitational collapse. We find two maps between solutions, one that relates fiveand six-dimensional solutions, and another that relates solutions in the same dimension by interchanging bubbles and black holes. To illustrate the richness of the phase structure and the non-uniqueness in the (µ, n) phase diagram, we consider in detail particular examples of the general class of solutions.

A new Modelica library for the modeling and simulation of 3-dimensional mechanical systems has been developed. It will be freely available in the Modelica standard library. Furthermore, the Dymola simulation environment has been considerably enhanced to support the needed features. The MultiBody library is first presented from a user's point of view. Furthermore, all essential details of the implementation are described. The library includes features that are usually not available in other multi-body software, such as analytic handling of a large class of kinematical loops, or the arbitrary connection feature of objects. For example, series connection of 3D line force components is possible.