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Determination of reinforcement degrees in constructing large-scale structures by using multiclass support vector machines

Recently, as the birthrate declines and the population ages, labor shortage is becoming an issue in the construction industry, especially in the field of building and maintaining large-scale infrastructure. This paper focuses on determination of the reinforcement degrees at construction sites of a large-scale structure, which has traditionally required the experience and skill of experts. We formulate the decision as a recognition problem based on the various risk scores observed at each section of the construction site, which can resolve the inconsistency in the structure data by using risk scores of the current and previous sections, and we introduce multiclass SVMs that exploit the monotonicity of the data. Finally, we apply the proposed methods to data at various real construction sites of one kind of large-scale structure, where we train the SVMs on known datasets obtained at many known sites of the structure, and then evaluate the classification rates of the obtained classifiers to the unknown dataset of the structure.

COVID-19 and Authoritarianism: Two Strategies of Engaging Fear

This paper considers ways in which rulers can respond to, generate, or exploit fear of COVID-19 infection for various ends, and in particular distinguishes between ‘fear-invoking’ and ‘fear-minimising’ strategies. It examines historical precedent for executive overreach in crises and then moves on to look in more detail at some specific areas where fear is being mobilised or generated: in ways that lead to the suspension of civil liberties; that foster discrimination against minorities; and that boost the personality cult of leaders and limit criticism or competition. Finally, in the Appendix, we present empirical work, based on the results of an original survey in Brazil, that provides support for the conjectures in the previous sections. While it is too early to tell what the longer-term outcomes of the changes we note will be, our purpose here is simply to identify some warning signs that threaten the key institutions and values of democracy.

A periodic Chikungunya model with virus mutation and transovarial transmission

In this paper, a Chikungunya dynamical model with virus mutation and transovarial transmission is developed, which incorporates the effect of seasonal temperature changes on disease transmission through time-dependent parameters. Firstly, the threshold parameter R0m that determines the persistence and extinction of mosquito populations is given, and then the disease reproduction number R0 is defined. Secondly, it is proved that if R0m > 1 and R0 < 1, the disease disappears; if R0m > 1 and R0 > 1, then Chikungunya with mutants and non-mutants will persist simultaneously. Finally, a case study is carried out with the data in Kerala, India, where the virus mutation causes the outbreak of Chikungunya. Data on newly confirmed human cases in the state between 2007 and 2010 is fitted and the theoretical results obtained in the previous section are validated. In addition, the effects of seasonal temperature change, virus mutation and transovarial transmission on the prevalence of the disease are studied by numerical simulations from different aspects.2020 MSC: 34K13; 37N25; 92D30.

Стохастическая оптимизация в задаче цифрового предыскажения сигнала

In this paper, we test the performance of some modern stochastic optimization methods and practices in application to digital pre-distortion problem, that is a valuable part of processing signal on base stations providing wireless communication. In first part of our study, we focus on search of the best performing method and its proper modifications. In the second part, we proposed the new, quasi-online, testing framework that allows us to fit our modelling results with the behaviour of real-life DPD prototype, retested some selected of practices considered in previous section and approved the advantages of the method occured to be the best in real-life conditions. For the used model, maximum achieved improvement in depth was 7% in standard regime and 5% in online one (metric itself is of logarithmic scale). We also achieved a halving of the working time preserving 3% and 6% improvement in depth for the standard and online regime, correspondingly. All comparisons are made to the Adam method, which was highlighted as the best stochastic method for DPD problem in paper [Pasechnyuk et al., 2021], and to the Adamax method, that is the best in the proposed online regime.

Geometry of Curves with Fractional Derivatives in Lorentz Plane

In this paper, the geometry of curves is discussed based on the Caputo fractional derivative in the Lorentz plane. Firstly, the tangent vector of a spacelike plane curve is defined in terms of the fractional derivative. Then, by considering a spacelike curve in the Lorentz plane, the arc length and fractional ordered frame of this curve are obtained. Later, the curvature and Frenet-Serret formulas are found for this fractional ordered frame. Finally, the relation between the fractional curvature and classical curvature of a spacelike plane curve is obtained. In the last part of the study, considering the timelike plane curve in the Lorentz plane, new results are obtained with the method in the previous section.

Redesigning a Research Methods Course with Personalized, Interactive OER: A Case Study of Student Perceptions and Performance

This case study examines student learning outcomes derived from the redesign of an undergraduate child development research methods course, replacing a commercial textbook with Open Educational Resources (OER), which were remixed into interactive lessons. Using survey and exam performance data, two areas were evaluated: 1) students' experiences with the OER lessons; and (2) students' exam results from two OER sections compared to two previous commercial textbook sections taught by the same instructor. No significant differences in exam performance between the two groups were observed; however, student perceptions of the OER lessons indicated strong satisfaction. Implications of these findings, such as OER benefits for teaching and learning, are discussed.

On Involutes of Admissible Non-Lightlike Curves in Pseudo-Galilean 3-Space

This paper aims to investigate the theory of involutes of admissible non-lightlike curves in pseudo-Galilean 3-space. In the second section of this paper, we give fundamental concepts of pseudo-Galilean 3-space and curves over this space together with their casual properties. In section three, the involute of admissible non-lightlike curves in pseudo-Galilean 3-space is defined. Furthermore, the properties of involutes of admissible non-lightlike curves are also investigated by applying the fundamental properties provided in section 2. In the last part but not least, we give some numerical examples as applications of the theorems and corollaries which are derived in the previous section.

Observation: Setting the Foundation for Creativity and Innovation.

Observation: Setting the Foundation for Creativity and Innovation.

SARS-CoV-2 Diagnostics Based on Nucleic Acids Amplification: From Fundamental Concepts to Applications and Beyond.

COVID-19 pandemic ignited the development of countless molecular methods for the diagnosis of SARS-CoV-2 based either on nucleic acid, or protein analysis, with the first establishing as the most used for routine diagnosis. The methods trusted for day to day analysis of nucleic acids rely on amplification, in order to enable specific SARS-CoV-2 RNA detection. This review aims to compile the state-of-the-art in the field of nucleic acid amplification tests (NAATs) used for SARS-CoV-2 detection, either at the clinic level, or at the Point-Of-Care (POC), thus focusing on isothermal and non-isothermal amplification-based diagnostics, while looking carefully at the concerning virology aspects, steps and instruments a test can involve. Following a theme contextualization in introduction, topics about fundamental knowledge on underlying virology aspects, collection and processing of clinical samples pave the way for a detailed assessment of the amplification and detection technologies. In order to address such themes, nucleic acid amplification methods, the different types of molecular reactions used for DNA detection, as well as the instruments requested for executing such routes of analysis are discussed in the subsequent sections. The benchmark of paradigmatic commercial tests further contributes toward discussion, building on technical aspects addressed in the previous sections and other additional information supplied in that part. The last lines are reserved for looking ahead to the future of NAATs and its importance in tackling this pandemic and other identical upcoming challenges.

Mechanistic Insights into WO3 Sensing and Related Perspectives.

Tungsten trioxide (WO3) is taking on an increasing level of importance as an active material for chemoresistive sensors. However, many different issues have to be considered when trying to understand the sensing properties of WO3 in order to rationally design sensing devices. In this review, several key points are critically summarized. After a quick review of the sensing results, showing the most timely trends, the complex system of crystallographic WO3 phase transitions is considered, with reference to the phases possibly involved in gas sensing. Appropriate attention is given to related investigations of first principles, since they have been shown to be a solid support for understanding the physical properties of crucially important systems. Then, the surface properties of WO3 are considered from both an experimental and first principles point of view, with reference to the paramount importance of oxygen vacancies. Finally, the few investigations of the sensing mechanisms of WO3 are discussed, showing a promising convergence between the proposed hypotheses and several experimental and theoretical studies presented in the previous sections.

Characterizations of Adjoint Curves According to Alternative Moving Frame

In this paper, the adjoint curve is defined by using the alternative moving frame of a unit speed space curve in 3-dimensional Euclidean space. The relationships between Frenet vectors and alternative moving frame vectors of the curve are used to offer various characterizations. Besides, ruled surfaces are constructed with the curve and its adjoint curve, and their properties are examined. In the last section, there are examples of the curves and surfaces defined in the previous sections.

Computational prediction of the drilling rate of penetration (ROP): A comparison of various machine learning approaches and traditional models

Rate of penetration (ROP) prediction, can assist precise planning of drilling operations and can reduce drilling costs. However, easy estimation of this key factor by traditional or experimental models is very difficult. This requires comparing available models for achieving the best prediction approach. In this study, four machine learning (ML) methods and two traditional ROP models were utilized to predict ROP. ML techniques include multilayer perceptron neural network (MLPNN), radial basis function neural network (RBFNN), adaptive neuro-fuzzy inference system (ANFIS), and support vector regression (SVR). MLPNN, ANFIS, and RBFNN methods were trained with four meta-heuristic algorithms including particle swarm optimization (PSO), ant colony optimization (ACO), differential evolution (DE), and genetic algorithm (GA). The backpropagation (BP) algorithm was also incorporated to train the ANFIS and MLPNN methods as a conventional method. For comparison purposes, the traditional ROP models of Bourgoyne and Young (BYM) and Bingham were also implemented in combination with four meta-heuristic algorithms. The required data were collected from the mud logging unit (MLU) and the final report of a drilled well located in southwestern of Iran. In the MLU, the information of different sensors is firstly collected through the data communications protocols and sent to a master unit to be processed into relevant dimensions (i.e. create operational variables). In order to accurately record information, the sensors are calibrated at regular intervals. After removing the outliers, the overall noise of data was reduced by Savitzky-Golay (SG) smoothing filter. Then, in order to simulate a drilling process in a realistic manner and also to evaluate the performance of the models in approximating the penetration rate at greater depth of hole, the available data were divided into 6 sections based on depth. After that, sections 2 Data collection and preprocessing , 3 Methodology , 4 Model development and ROP estimation , 5 Discussion and results , 6 Conclusion were separately used as a test dataset and all previous sections were considered as a training dataset. Results indicated that PSO-MLPNN achieved the highest performance in comparing with other developed models. The concluding remark is that ML models are more efficient and reliable than traditional models. In addition, combining ML models with meta-heuristic algorithms can achieve better results than conventional algorithms such as BP. The results of this study can be used as a practical guide for the management and planning of future well drilling. • Applying Savitzky-Golay (SG) filter to remove noise from data. • Data were divided into 6 sections. Section 2 to 6 were separately noted as test and the previous one(s) as training dataset. • Comparison of four machine learning (ML) methods and two traditional ROP models. • Coupling models with meta-heuristic algorithms and conventional algorithms. • PSO-MLPNNmodel showed the highest accuracy compared to others.

Review: Molecular Capture: The Animation of Biology, by Adam Nocek

Review: <i>Molecular Capture: The Animation of Biology</i>, by Adam Nocek

Geheimnis und Verborgenes im Mittelalter: Funktion, Wirkung, und Spannungsfelder von okkultem Wissen, verborgenen Räumen und magischen Gegenständen

Geheimnis und Verborgenes im Mittelalter: Funktion, Wirkung, und Spannungsfelder von okkultem Wissen, verborgenen Räumen und magischen Gegenständen

Why This Now? Theorizing Mindfulness and Communication

The essays in the previous special section illustrate diverse starting points communication scholarship can take when exploring mindfulness. This essay is a complement to the special section and explores how these scholars employ and refine mindfulness conceptualizations. The outlook for communication scholars interested in mindfulness research provides not a single perspective, but, rather, diverse views for theory development and application. Ideas for conceptualizing and theorizing mindfulness are delineated by examining the variety of axiological, ontological, and epistemological starting points seen in this collection of essays.

A re-examination of the liquidus surface of the Al–Fe–Ti system

Abstract The liquidus surface of the Al –Fe –Ti system has been reexamined. 34 different alloys have been studied by differential thermal analysis, and the temperatures of invariant reactions have been determined. By examining the as-cast samples by optical microscopy, X-ray diffraction and energy-dispersive spectrometry in a scanning electron microscope, the crystal structures and chemical compositions of the primary phases and two-phase aggregates have been established. In some cases, additional investigations were carried out in the transmission electron microscope. From the combined results of these investigations the solidification paths of the alloys were established leading to a revised representation of the liquidus surface of the Al –Fe –Ti system. A reaction scheme has been set up which shows phase equilibria that are consistent with previous solid-state isothermal sections.

Folic acid supplementation and malaria susceptibility and severity among people taking antifolate antimalarial drugs in endemic areas.

Folic acid supplementation and malaria susceptibility and severity among people taking antifolate antimalarial drugs in endemic areas.

Editorial Policy and Style Information

Editorial Policy and Style Information

Political realism and the quest for political progress

Political realism and the quest for political progress