Miracle-dz/UniFAR-FTUs huggingface dataset:
Guaranteed cost control via optimal parametric LQ design

For an optimal parametric linear quadratic (LQ) control problem, a design objective is to determine a controller of constrained structure such that the closed-loop system is asymptotically stable and an associated performance measure is optimized. In the presence of system uncertainty, the system obtained by parametric LQ design is further required to be robust in terms of maintaining the closed-loop stability with a guaranteed cost bound. This problem, referred to as robust optimal parametric LQ control with a guaranteed-cost bound, is addressed. A design method is proposed for finding an optimal controller that simultaneously guarantees robust stability and performance over a specified range of parameter variations. A versatile numerical algorithm is given for computing the robust optimal gains. The usefulness of the design method is demonstrated by the design of robust control of a VTOL helicopter. <<ETX>>
Turbo-EEPRML: An EEPR4 channel with an error-correcting post-processor designed for 16/17 rate quasi-MTR code

An EEPRML channel with a post processor has been developed for compensating for the degradation in performance due to noise correlation. This Turbo-EEPRML is designed for 16/17 rate quasi-MTR (QMTR) code. The proposed method has high performance and simple circuitry. Simulation showed that Turbo-EEPRML has a 2.0-2.5 dB coding gain over a conventional EPRML channel for 16/17 GCR code.
Computer-aided Creativity in Engineering Design

SUMMARY The study of creativity in industry is new as a scientific discipline. A landmark paper was presented by J. P. Guilford in 1950, where he suggested that psychologists should engage themselves in this field. A recent development is the application of the computer, A pioneering work is a master's thesis in 1984 by S. Hollander. Since then, several general-purpose programs have appeared. A program which simulates the creative thinking process was introduced in 1988. It covers the whole problem-solving process from problem analysis to selection and implementation of the solution. In the future, most programs will be dedicated, i.e. designed to solve special problems. Increasingly, they will be supplemented with graphics, colours, sounds and even scents, as thinking stimulators. As electronic mail becomes more widely used, distributed creative sessions in time and space may be organized. People in different geographic locations may participate and make a creative contribution to the problem-solving pro.
Designing Online Courses to Promote Student Retention

Although the issue of student retention is a campus-wide one, it is of special interest in online distance learning courses, where retention rates are reported to be lower than in face-to-face classes. Among the explanations and theories of retention rates in online courses, one that struck us as most useful is a structural one, namely, course design. The question we raise is, can online course designs promote student retention? In this article, we report on how we used Quality Matters to design and revise online courses in psychology and statistics. Quality Matters, a research-based initiative, advocates the use of eight general review standards to review online courses. In our psychology and statistics courses, our retention rate across multiple offerings of both courses is approximately 95%.
Most unexposed taut one-relator presentation 2-complexes are finitely unsplittable

The main result of this article is that among the family of one-relator presentation 2-complexes that might be expected to be finitely unsplittable (not the union of two proper subpolyhedra with finite first homology groups) almost all have this property. Included among these one-relator presentation 2-complexes are all generalized dunce hats. A generalized dunce hat is a 2-dimensional polyhedron created by attaching the boundary of a disk $\Delta$ to a circle $J$ via a map $f : \partial\Delta \rightarrow J$ with the property that there is a point $v$ in $J$ such that $f^{-1}(\{v\})$ is a finite set containing at least 3 points and $f$ maps each component of $\partial\Delta - f^{-1}(\{v\})$ homeomorphically onto $J - \{v\}$. The fact that generalized dunce hats are finitely unsplittable undermines a strategy for proving that the interior of the Mazur compact contractible 4-manifold $M$ is splittable in the sense of Gabai (i.e., $\text{int}(M) = U \cup V$ where $U$, $V$ and $U \cap V$ are each homeomorphic to Euclidean 4-space).
Quantitative predictions of photoelectron spectra in amorphous molecular solids from multiscale quasiparticle embedding

We present a first-principles-based multiscale simulation framework for quantitative predictions of the high-energy part of the ultraviolet photoelectron spectroscopy (UPS) spectra of amorphous molecular solids. The approach combines a deposition simulation, many-body Green's function theory, polarizable film embedding, and multimode electron-vibrational coupling and provides a molecular-level view on the interactions and processes giving rise to spectral features. This insight helps bridging the current gap between experimental UPS and theoretical models as accurate analyses are hampered by the energetic disorder, surface sensitivity of the measurement, and the complexity of excitation processes. In particular, this is relevant for the unambiguous determination the highest occupied molecular orbital energy (HOMO) of organic semiconductors, a key quantity for tailoring and engineering new optoelectronic devices. We demonstrate the capabilities of the simulation approach studying the spectrum of two isomers of 2-methyl-9,10-bis(naphthalen-2-yl)anthracene as archetypical materials showing a clearly separated HOMO peak in experiment. The agreement with experiment is excellent, suggesting that our approach provides a route for determining the HOMO energy with an accuracy better than 0.1 eV.
Interference cancellation technology in MIMO mobile cellular communication systems

Pioneering studies, showing a large increase in capacity of MIMO systems, don't take any external interference into consideration. However, in real propagation environments of cellular communications, channel reuse will cause the co-channel interference, which will result in the degradation of MIMO channel performance. Furthermore, the next generation cellular systems are quite likely to be completely IP-based, and unlike voice-centric network, they will generally have a low average activity factor of users and thus very tight frequency reuse factors. This will lead to more serious co-channel interference, which can be handled efficiently by interference cancellation (IC) technology. In this paper, after introducing MIMO technology in detail and analyzing the co-channel interference in cellular system and its cancellation methods, we will focus on a specific scheme based on an IC algorithm to combat the co-channel interference in MIMO channel. We will present and evaluate the simulation results of the scheme that is suitable for MIMO in cellular system.
From Harnack inequality to heat kernel estimates on metric measure spaces and applications

Aim of this short note is to show that a dimension-free Harnack inequality on an infinitesimally Hilbertian metric measure space where the heat semigroup admits an integral representation in terms of a kernel is suffcient to deduce a sharp upper Gaussian estimate for such kernel. As intermediate step, we prove the local logarithmic Sobolev inequality (known to be equivalent to a lower bound on the Ricci curvature tensor in smooth Riemannian manifolds). Both results are new also in the more regular framework of $RCD(K,\infty)$ spaces.
Maintaining Capabilities in CCD Production for the Astronomy Community

CCD detectors play a vital role in all aspects of optical astronomy. Critical to advancing research is the ability to partner with commercial foundries to produce custom devices that meet the needs of specific instruments. For more than 20 years, Teledyne DALSA Semiconductor was the primary industrial partner in the manufacturing of 150 mm wafers for CCDs. DALSA is migrating the manufacturing from 150mm to 200mm wafer diameter and will not be updating their CCD processing tools for the new format wafer. As a result, DALSA will no longer serve as a partner to the astronomy community in the manufacturing of CCDs. We recommend that the Department of Energy, National Science Foundation, and NASA jointly pursue a new commercial partner in CCD fabrication to maintain capabilities in custom CCD design for astronomy applications.
Tensor methods for finding approximate stationary points of convex functions

In this paper, we consider the problem of finding ε-approximate stationary points of convex functions that are p-times differentiable with ν-Hölder continuous pth derivatives. We present tensor methods with and without acceleration. Specifically, we show that the non-accelerated schemes take at most iterations to reduce the norm of the gradient of the objective below given . For accelerated tensor schemes, we establish improved complexity bounds of and , when the Hölder parameter is known. For the case in which ν is unknown, we obtain a bound of for a universal accelerated scheme. Finally, we also obtain a lower complexity bound of for finding ε-approximate stationary points using p-order tensor methods.
Learning of hierarchical control structures

The use of externally imposed hierarchical structures to reduce the complexity of learning control is common. However it is clear that the learning of the hierarchical structure by the machine itself is an important step towards more general and less bounded learning. Presented in this paper is a nested Q-learning technique that generates a hierarchical control structure as the robot interacts with its world. These emergent structures combined with learned bottom-up reactive reactions result in a flexible hierarchical control system.
Evolved massive stars at low-metallicity

We present a clean, magnitude-limited (IRAC1 or WISE1 ≤ 15.0 mag) multiwavelength source catalog for the Large Magellanic Cloud (LMC). The catalog was built by crossmatching (1″) and deblending (3″) between the source list of Spitzer Enhanced Imaging Products and Gaia Data Release 2, with strict constraints on the Gaia astrometric solution in order to remove the foreground contamination. It is estimated that about 99.5% of the targets in our catalog are most likely genuine members of the LMC. The catalog contains 197 004 targets in 52 different bands, including two ultraviolet, 21 optical, and 29 infrared bands. Additional information about radial velocities and spectral and photometric classifications were collected from the literature. We compare our sample with the sample from Gaia Collaboration (2018, A&A, 616, A12), indicating that the bright end of our sample is mostly comprised of blue helium-burning stars (BHeBs) and red HeBs with inevitable contamination of main sequence stars at the blue end. After applying modified magnitude and color cuts based on previous studies, we identified and ranked 2974 red supergiant, 508 yellow supergiant, and 4786 blue supergiant candidates in the LMC in six color-magnitude diagrams (CMDs). The comparison between the CMDs from the two catalogs of the LMC and Small Magellanic Cloud (SMC) indicates that the most distinct difference appears at the bright red end of the optical and near-infrared CMDs, where the cool evolved stars (e.g., red supergiant stars (RSGs), asymptotic giant branch stars, and red giant stars) are located, which is likely due to the effect of metallicity and star formation history. A further quantitative comparison of colors of massive star candidates in equal absolute magnitude bins suggests that there is essentially no difference for the BSG candidates, but a large discrepancy for the RSG candidates since LMC targets are redder than the SMC ones, which may be due to the combined effect of metallicity on both spectral type and mass-loss rate as well as the age effect. The effective temperatures (Teff) of massive star populations are also derived from reddening-free color of (J − KS)0. The Teff ranges are 3500 < Teff < 5000 K for an RSG population, 5000 < Teff < 8000 K for a YSG population, and Teff > 8000 K for a BSG population, with larger uncertainties toward the hotter stars.
A new high definition zoom method based on compounded direct pixel beamforming for medical ultrasound imaging: preliminary results

Conventional ultrasound imaging based on scan conversion suffers from blurring artifacts caused by interpolation[1]. Especially, when zooming an image for enlarging lesions during scan conversion (i.e., read-zoom), this blurring artifact becomes severe. To reduce blurring artifacts, a write-zoom method was previously proposed. However, it still presents blurring artifacts and lowers the frame rate due to increased line density. In this paper, a new high definition zoom method based on compounded direct pixel beamforming (CDPB) capable enhancing the detail and boundary of lesions is presented. The performance of the proposed method was evaluated with phantom and in vivo experiments by measuring the information entropy contrast (IEC). The radio-frequency channel data were acquired by using a 3.5-MHz convex array transducer with the SonixTouch research platform (Ultrasonix Medical Corp., Vancouver, BC, Canada). The enlarged images using a new high-definition zoom method based on CDPB (i.e., HDZ-CDPB) with 128 transmit scanlines were reconstructed along with read- and write zoom (RZ and WZ) images based on scan conversion by using 128 and 256 transmit scanlines, respectively. From the phantom experiments, the IEC value with the proposed HDZCDPB method was enhanced by maximally 42% and 29% compared to the RZ and WZ methods, respectively. This preliminary results indicate that the proposed HDZ-CDPB method would be useful for generating a high definition ultrasound zoom image with improved image quality compared to the conventional scan conversion based methods (i.e., RZ and WZ) while achieving the high frame rate.
A row-invariant parameterized algorithm for integer programming

A long line of research on fixed parameter tractability of integer programming culminated with showing that integer programs with n variables and a constraint matrix with tree-depth d and largest entry D are solvable in in time g(d,D)poly(n) for some function g, i.e., fixed parameter tractable when parameterized by tree-depth d and D. However, the tree-depth of a constraint matrix depends on the positions of its non-zero entries and thus does not reflect its geometric nature, in particular, is not invariant under row operations. We consider a parameterization of the constraint matrix by a matroid parameter called branch-depth, which is invariant under row operations. Our main result asserts that integer programs whose matrix has branch-depth d and largest entry D are solvable in time f(d,D)poly(n). Since every constraint matrix with small tree-depth has small branch-depth, our result extends the result above. The parameterization by branch-depth cannot be replaced by the more permissive notion of branch-width.
Performance Assessment of Kron Reduction in the Numerical Analysis of Polyphase Power Systems

This paper investigates the impact of Kron reduction on the performance of numerical methods applied to the analysis of unbalanced polyphase power systems. Specifically, this paper focuses on power-flow study, state estimation, and voltage stability assessment. For these applications, the standard Newton-Raphson method, linear weighted-least-squares regression, and homotopy continuation method are used, respectively. The performance of the said numerical methods is assessed in a series of simulations, in which the zero-injection nodes of a test system are successively eliminated through Kron reduction.
Explorations of the speed-accuracy trade-off in Memory Based Learning algorithms

In this report the trade-off between accuracy and speed of several variations of memory based learning (MBL) algorithms is explored. So-called greedy algorithms gain speed by ignoring some information (presumed to be less relevant to the learning task) provided by the training data. Generally, the speed gain comes at the cost of accuracy. How much speed is gained and at what cost to accuracy depends on the learning task and the data used. Insight into the relation between data characteristics and learning task on the one hand and accuracy and speed obtained by greedy algorithms on the other hand, will be helpful when one has to make a choice between algorithms given a set of data and a learning task. Experiments on two natural language learning tasks were done: text chunking and shallow parsing. The latter task was performed using different feature sets. Results indicate that the number of values of the most informational feature(s) and the complexity of the learning task, are important factors to take into account when deciding on an algorithm to use. On the task of text chunking one of the greedy algorithms obtained a slighty, but significantly, higher accuracy than the non-greedy algorithm, and its classification speed was two times higher.
Mathematical Analysis of Electromagnetic Plasmonic Metasurfaces

We study the anomalous electromagnetic scattering in the homogenization regime, by a subwavelength thin layer of periodically distributed plasmonic nanoparticles on a perfect conducting plane. By using layer potential techniques, we derive the asymptotic expansion of the electromagnetic field away from the thin layer and quantitatively analyze the field enhancement due to the mixed collective plasmonic resonances, which can be characterized by the spectra of periodic Neumann-Poincare type operators. Based on the asymptotic behavior of the scattered field in the macroscopic scale, we further demonstrate that the optical effect of this thin layer can be effectively approximated by a Leontovich boundary condition, which is uniformly valid no matter whether the incident frequency is near the resonant range but varies with the magnetic property of the plasmonic nanoparticles. The quantitative approximation clearly shows the blow-up of the field energy and the conversion of polarization when resonance occurs, resulting in a significant change of the reflection property of the conducting plane. These results confirm essential physical changes of electromagnetic metasurface at resonances mathematically, whose occurrence was verified earlier for the acoustic case \cite{ammari2017bubble} and the transverse magnetic case \cite{ammari2016mathematical}.
Deep social collaborative filtering

Recommender systems are crucial to alleviate the information overload problem in online worlds. Most of the modern recommender systems capture users' preference towards items via their interactions based on collaborative filtering techniques. In addition to the user-item interactions, social networks can also provide useful information to understand users' preference as suggested by the social theories such as homophily and influence. Recently, deep neural networks have been utilized for social recommendations, which facilitate both the user-item interactions and the social network information. However, most of these models cannot take full advantage of the social network information. They only use information from direct neighbors, but distant neighbors can also provide helpful information. Meanwhile, most of these models treat neighbors' information equally without considering the specific recommendations. However, for a specific recommendation case, the information relevant to the specific item would be helpful. Besides, most of these models do not explicitly capture the neighbor's opinions to items for social recommendations, while different opinions could affect the user differently. In this paper, to address the aforementioned challenges, we propose DSCF, a Deep Social Collaborative Filtering framework, which can exploit the social relations with various aspects for recommender systems. Comprehensive experiments on two-real world datasets show the effectiveness of the proposed framework.
Condensed Ricci curvature of complete and strongly regular graphs

We study a modified notion of Ollivier's coarse Ricci curvature on graphs introduced by Lin, Lu, and Yau in [11]. We establish a rigidity theorem for complete graphs that shows a connected finite simple graph is complete if and only if the Ricci curvature is strictly greater than one. We then derive explicit Ricci curvature formulas for strongly regular graphs in terms of the graph parameters and the size of a maximal matching in the core neighborhood. As a consequence we are able to derive exact Ricci curvature formulas for strongly regular graphs of girth 4 and 5 using elementary methods. An example is provided that shows there is no exact formula for the Ricci curvature for strongly regular graphs of girth $3$ that is purely in terms of graph parameters.
Electrocardiogram Recording with Pasteless Electrodes

Experimentation regarding various aspects of a technique for recording electrocardiographic potentials from unprepared skin, without the use of conventional paste, is described. Because of the relatively high skin-to-electrode impedances encountered without electrolytic paste, high input impedance amplifiers must be utilized for acquisition of the signal. In order to minimize susceptibility to external electrostatic and electromagnetic interference, an inherent problem with high input impedance amplifiers, buffer amplifiers were incorporated directly within the electrode housing. Of the different metals tested, stainless steel proved to be the most stable skin contact material for pasteless operation. The integrated electrode-buffer amplifiers described comply with specifications of the American Heart Association and should prove useful as a direct replacement for conventional paste-type electrodes in existing clinical EKG equipment as well as for long-term applications such as space missions and intensive-care-unit patient monitoring, where frequent attention to the electrodes is inconvenient.
Exact sequence between real and complex bivariant K theories and application to the Z2 pairing

We give some formulas for the ZZ pairing in KO theory using a long exact sequence for bivariant K theory which links real and complex theories. This is discussed under the framework of real structures given by antilinear operators verifying some symmetries. Topological phases protected by time reversal symmetry from condensed matter physics will be discussed.
Automatic Construction of Entity Semantic Representation Model Based on Dependency Analysis

The entity semantic representation model (ESRM), which considers an entity as a set of attributes and corresponding values, is very useful for various applications. This paper proposes an approach for extracting new attributes and values from related unstructured documents. In our approach, the extraction process is formulated as the sequence labeling task. According to the predefined entity structure, the labeled data for training annotator are achieved automatically. The CRFs based annotator is trained to annotate the sentence which maybe contains the new attributes and values. And then, in terms of a decision process with scoring algorithm, new attributes and values are identified and fill into the predefined entity representation model. The experiments show that the proposed method improves the performance of extraction with a higher accuracy.