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The given text discusses various mathematical equations and concepts related to the bending behavior of fibers. It addresses issues with certain expressions and proposes alternative models that take into account the change in curvature of the fibers. The text also responds to criticisms raised by another researcher and provides clarification on certain equations and variables. Overall, the text provides a technical and detailed analysis of the topic of fiber bending. [Extracted from the article]

Organized as a satellite to the annual Conference on Complex Systems, the Evolution of Cultural Complexity held its inaugural workshop in Tempe, Arizona, in 2015, a second in Cancún, Mexico, in 2017, and a third in Thessaloniki, Greece, in 2018. The goal of those satellite sessions was to bring together a community of researchers from different fields who had interests in the evolution of cultural complexity. This special issue includes three papers that grew out of those workshops and one paper that was solicited. Each brings a unique perspective on myriad issues that surround how and why culture evolves. One issue that is key to understanding the evolution of cultural complexity—and it is addressed in the papers included here—is how humans learn and transmit information and the rate at which it is learned and transmitted. [ABSTRACT FROM AUTHOR]

The paper ' Zur Dynamik elastisch gekoppelter Punktsysteme ' by Schrödinger (1914) does not seem to have attracted the attention that it deserves. We translate it into English here and we discuss its results in detail, with a view to its possible influence in the modern theories of generalised continua. The clever solution found, in terms of Bessel functions, by Schrödinger of the problem of the vibrations of a linear infinite chain of molecules gives some important methodological hints for contemporary research. [ABSTRACT FROM AUTHOR]

Students of European integration have produced an enormous amount of literature on the intergovernmental negotiations that led to the establishment of such organizations as the OEEC, the EEC and EFTA. However, only a few have devoted substantial attention to the international contacts between companies that attempted to undermine the integration process by building private trade barriers that would replace those that governments had agreed to remove. The paper producers began to build such barriers soon after EFTA and the EEC had been set up. Although these attempts were not always successful, the industrialists did manage to create arrangements that were substantially more extensive in their geographical and product scope than those that had existed before. The British government and the EEC were reluctant to challenge these arrangements, and in some cases even actively promoted them. The interwar decades are widely considered to be the ‘golden era’ for international cartels; but for the paper cartels, the ‘golden era’ began in the 1960s, when previous bilateral links were replaced with multilateral ones. [ABSTRACT FROM PUBLISHER]

Based on data analysis and documentary research, this paper indicates that the main causes which negatively affect the preservation of paper documents in China are acidification and damaging pests such as moths and insects. The priorities for the preservation of Chinese documents are protecting the documents against air pollution and controlling pests and insects. Taking these problems and the Chinese national condition into account, the paper proposes to create a favorable microenvironment for decreasing the acidification of papers and to adopt various measures for controlling pests and insects. [ABSTRACT FROM AUTHOR]

Leveraging Rubik Tables, the authors designed a constant-factor optimal algorithm for stack rearrangement and multi-robot motion planning problems under extreme robot density. A general algorithm and several specialized algorithms are then introduced to solve the problem, constructing a product between the event model and a specification automaton. Toward that, the authors analyze closed-loop dynamics to identify conditions that lead to deadlock and, using duality theory and KKT conditions, derive geometric properties of robot configurations in deadlock. [Extracted from the article]

This special issue is organized by selected papers presented at International Symposium on Robotics Research (ISRR 2019), held on October 6-10, 2019, at Hanoi, Vietnam. The guest editors would like to express their sincere gratitude to the authors for their patience by the review process that was slowed down due to the difficulties caused by the worldwide pandemic and are very delighted this special issue is finally complete. The robotics fundamental contributions are about algorithmic foundation for manipulation and innovative robotics design and two papers are included for each topic. [Extracted from the article]

This paper concerns The Big Issue, a magazine that is sold on the streets by homeless people in the UK, and describes how it was started, who reads it and how the homeless are involved. It also describes the work of The Big Issue Foundation and discusses the growing number of street papers being produced in many other countries and the development of an international network of street papers. [ABSTRACT FROM PUBLISHER]

The purpose of these comments is to correct some mischaracterizations of my work with Paul Bahn that Froese et al. make in their latest paper “Are altered states of consciousness detrimental, useful or helpful for the origins of symbolic cognition? A response to Hodgson and Lewis-Williams”. Additionally I discuss neuropsychological errors occurring in that paper. [ABSTRACT FROM AUTHOR]

The fracture phenomenon of fastener clips occurs frequently in the sections with serious rail corrugation of high-speed railway, which brings huge potential safety hazards to track service and driving safety. In order to prevent the vibration fatigue fracture of fastener clips in high-speed railway, a dynamic vibration absorber (DVA) for clips is proposed in this paper to suppress the primary sensitive frequency of the corresponding resonant of clips. Firstly, based on the optimal design theory of DVA, a parameters design method of ring-shaped DVA suitable for clips is proposed. Secondly, the vibration characteristics of the high-speed railway fastener system are investigated, and the main reason for the fastener clips fracture is analyzed by simulation analysis combined with filed test. Then, focusing on the primary resonant frequency of clips, the vibration reduction effect of the ring-shaped DVA is analyzed. The results show that the ring-shaped DVA can change the natural frequency of the clip system, reduce the vibration response in the range of the original resonant frequency, and avoid the resonance phenomenon. Finally, the influences of mass ratio, frequency ratio, and damping ratio on the vibration reduction effect are analyzed, and the effectiveness of the parameters design method of ring-shaped DVA proposed in this paper is further proved. The research results can provide methodological support for the anti-breakage design of high-speed railway fastener clips. [ABSTRACT FROM AUTHOR]

Information about several papers discussed at the International Exascale Software Project (IESP) workshop on computer software and hardware related subject is presented. White papers addressing topics, that includes programming models, system software and parallel programming, were submitted by different groups. Information about development in exascale and high speed computing system as discussed in the workshop is also presented.

Growing inequalities are one of the most pressing issues for cities, threatening the fulfilment of the rights of millions of urban residents. With three-quarters of cities now more unequal than in 1996, urban inequality has increasingly been recognized as a key global challenge.([1]) The Sustainable Development Goals and the UN-Habitat New Urban Agenda have recognized that addressing growing inequality has to be a priority for local and national governments, establishing global commitments that are in dialogue with localized efforts of urban transformation towards more equal futures. Importantly, this paper invites us to see the pandemic experiences and responses as a part of the expression of state power and wider classist inequalities which served to exclude vendors from public space and life, and which might in turn create trajectories that exacerbate inequalities. [Extracted from the article]

Transparent objects are encountered frequently in our daily lives, yet recognizing them poses challenges for conventional vision sensors due to their unique material properties, not being well perceived from RGB or depth cameras. Overcoming this limitation, thermal infrared cameras have emerged as a solution, offering improved visibility and shape information for transparent objects. In this paper, we present TRansPose, the first large-scale multispectral dataset that combines stereo RGB-D, thermal infrared (TIR) images, and object poses to promote transparent object research. The dataset includes 99 transparent objects, encompassing 43 household items, 27 recyclable trashes, 29 chemical laboratory equivalents, and 12 non-transparent objects. It comprises a vast collection of 333,819 images and 4,000,056 annotations, providing instance-level segmentation masks, ground-truth poses, and completed depth information. The data was acquired using an FLIR A65 thermal infrared camera, two Intel RealSense L515 RGB-D cameras, and a Franka Emika Panda robot manipulator. Spanning 87 sequences, TRansPose covers various challenging real-life scenarios, including objects filled with water, diverse lighting conditions, heavy clutter, non-transparent or translucent containers, objects in plastic bags, and multi-stacked objects. Supplementary material can be accessed from the following link: https://sites.google.com/view/transpose-dataset. [ABSTRACT FROM AUTHOR]

In scholarly debates, Ludwik Fleck's post-war paper 'Problemy naukoznawstwa [Problems of the Science of Science]', published in 1946, has been taken unanimously to illustrate the epistemology expounded in his monograph Genesis and Development of a Scientific Fact. The paper has also been seen to support parts of the received view of Fleck, notably that he manufactured an anti-typhus vaccine while imprisoned in Buchenwald. However, a different narrative emerges when comparing Fleck's paper with other accounts, also published in 1946 and written by other prisoners alluded to by Fleck in his paper. The situation is further complicated by four papers, published in prestigious scientific journals between 1942 and 1945, by the German medical leader of the typhus studies accounted for by Fleck. In addition, a thus-far neglected paper by Fleck, published in 1946 and summarizing his observations on typhus, discloses his role in the Buchenwald studies. Despite the obvious difficulties with tracing the history behind these works, notably the one on Nazi science, the contention is that what was attempted in Buchenwald in the name of science amounted to pseudoscience. This conclusion is amply supported not only by the accounts given by Fleck's fellow prisoners, but also by his own post-war paper on typhus. Based on the above findings, it is suggested that the mythology about Fleck, established in the 1980s, has been accomplished by a selective reading of his papers and also that the role played by Fleck was more complex than has so far been contemplated. [ABSTRACT FROM AUTHOR]

The vibration analysis of large and complex structures such as ships is difficult, because a vibrating ship hull (or its components) exhibits quite different vibration characteristics. Technological developments offer new concepts, definitions and comprehensive studies in the ship vibration field. The aim of this paper (bibliography) is to list references to papers, conferences, and proceedings dealing with ship vibrations that were published between January 2000 and April 2003. It contains 64 bibliographic references. The following types of ship vibrations are included: sea conditions, structural analysis, machine components, ship propulsive system, ship machines and special studies. Moreover, basic and brief information (reference, publication type, simulation models, utilizing methods and/or models, examined subject and/or problem) about grouped references has been given in the tables. So, this review paper not only lists references to papers at the millennium, but also helps researchers in their studies on ship vibration to find the necessary references quickly and practically. [ABSTRACT FROM AUTHOR]

The article presents comments concerning Eva Hedfors' paper on Ludwik Fleck. It argues that Hedfors proposes an informed reading of Fleck which aims to contest the mythology of the latter. It explores the claim of Hedfors that the work of Fleck is poorly done, meaningless and of doubtful ethical value. It emphasizes that the views of Fleck on science is aimed at legitimating his own scientifically weak research. It examines the preface made by Hedfors to her thesis wherein she elaborates that when she first read Fleck, she found an interest in his writings.

The article focuses on the Science and Technology Studies (STS) community's view toward politics which is offered by philosopher Gerard de Vries. The author states that de Vries' general critique against most of science studies is that people are so busy renewing some feature of scientific practice that people took off the shelf whatever political theory they had. The author explains that science studies has made people realize that politics has always been issue-oriented. It notes that the paper of de Vries reminds that people have been good at tracing the constant innovations of science and technology but have been lazy in expecting that all those new matters will find a place inside the vast dome of already assembled democratic politics.

Responds to comments made on the paper 'Foam Plastic Thermal Insulation in Low-Sloped Roofing Systems,' which appeared in the April 2002 issue of the 'Journal of Thermal Envelope & Building Science.' Phenolic foam insulation; Concentration of corrosion on the steel deck underneath insulation board joints; Vapor diffusion modelling; Acid barriers.

Since the transmission path of inter-shaft bearing-fault signal is complex, a fault feature extraction method based on hierarchical permutation entropy (HPE) and locally linear embedding (LLE) algorithm is proposed in this paper. In this method, HPE is utilized to extract fault information of signals, and LLE is utilized to reduce and fuse high-dimensional fault features of multi-sensors to construct fault samples. Then, the random forest (RF) model is established to diagnose the faults of the inter-shaft bearings. The fault simulation test rig with the inter-shaft bearing is built to simulate the normal bearing, inner ring fault, outer ring fault, and rolling ball fault, and the data are collected to verify the HPE-LLE-RF fault diagnosis algorithm of inter-shaft bearings established in this paper. The experimental results show that the proposed algorithm can extract the fault features of inter-shaft bearings effectively with a fault diagnosis accuracy of 93.3% without overfit phenomenon. [ABSTRACT FROM AUTHOR]

Calls for papers for several conferences on engineering design and management in 2001.

Presents information for authors contributing papers to engineering conferences from July 2001 to May 2003.

Presents information for authors contributing papers to engineering conferences as of June 2001.

Presents a call for papers on topics related to structural mechanics. Boundary element technology; Computer-aided optimum design of structures; Marine technology.

Calls for the submission of research papers on several congresses about mechanics and applied mechanics which will be held on January 2001 to May 2003.

The article focuses on sociologist Sergio Sismondo's paper on constructivism. Sismondo's paper puts into focus disagreements and differences in understanding between those who have been associated with constructivism and those who are not. In defining ontology as part of historical experience, constructivism makes a characteristic shift, it takes a philosophical question or concept and reconstructs it within the domain of empirical analysis and theory. Constructivism owns many questions to philosophy, a fact picked up very well in Sismomdo's paper. What is often less understood is that, for constructivist studies, what is important and what is not just the question, it is the shift. In other words, these studies display mentality towards philosophical concepts, and it is where they run to and how they reformulated the issue that account for their own interest. Sismondo misconstrues the thesis that the world is a consequence, rather than merely a precondition, of scientific accounts. This is the sense in which he makes it appear as if the material world were an automatic consequence of scientific knowledge.

A set of 316 commentaries by authors of highly-cited papers was reviewed, to identify any difficulty encountered by the authors in producing or publishing their articles. The commentaries were selected from those published each week in the Citation Classic[SUPR] feature of Current Contents. According to their commentaries, a small proportion (5.7%) of the authors of these papers had some difficulty when doing the research, or when trying to publish the results. Three more highly-cited papers which had also encountered difficulties in getting published were identified from Citation Classic[SUPR] commentaries: one of them was co-authored by a Nobel Prize winner. Three of the papers which encountered publication problems are the most cited from their respective journals. In part, the problematic papers reported innovative methods or theories, or presented new interpretations of previous data. Those in the peer review system should have access to these findings, to improve their review of innovative work. Evaluative criteria that are too narrow can sometimes lead to the initial rejection of very important papers. [ABSTRACT FROM AUTHOR]

Classical analyses of differences among the sciences has measured social but not cognitive structure. This paper suggests a method for describing differences among fields in the processes of knowledge growth. The method examines closely what is said about a particular scientific paper when it is cited in later works, and traces changes over time, if they occur. A comparative analysis of cases drawn from neuropharmacology and the sociology of science is used to illustrate the approach. The two papers analyzed shown strong differences in the level of generality at which the contents of the original papers are cited. Lack of change over time in how the sociology of science paper is cited is attributed to the lack of attention to its main empirical knowledge claim. [ABSTRACT FROM AUTHOR]

In this paper, a new dynamic photogrammetry method using an unmanned aerial vehicle (UAV) is proposed and the UAV-based operational modal analysis method is established. The presented dynamic photogrammetry method can measure the dynamic displacements of structure using one or two cameras. However, it is difficult to use fixed cameras or handheld cameras to measure the dynamic responses for some outdoor structures, because it is hard to reach for measurement or maintenance sometimes. Therefore, UAV is an effective alternative and the homography-based perspective rectification method can be used to correct the UAV images. However, the presented methods use only four calibration points. Additionally, there is still obvious signal drift in the extracted dynamic responses. In this paper, a new time varying homography matrix, calculated using n calibration points, is proposed here for the first time to correct the perspective distortion for image at different time and the relative displacements are used to eliminate the influence of UAV in-plane motion. The influence analysis of UAV vibration and the method to eliminate the UAV vibration are the novelty of this paper. And then, the UAV-based operational modal analysis method is proposed. The proposed method is verified using a plane frame structure in laboratory. The results show that the proposed method can effectively eliminate the vibration of UAV and identify the structural modal parameters. Under the impulse excitation and white noise excitation, when the calibration points n is larger than 60, the relative errors of natural frequency and damping ratio are less than 0.4% and 5.45%, respectively. And the MAC values are all greater than 0.99. Meanwhile, the influence of the number of adopted calibration points on modal parameters identification is considered in the experiment and the advised value is given. [ABSTRACT FROM AUTHOR]

Kalman filter has emerged as a powerful tool for unbalance identification in rotating machinery. Recently, the augmented Kalman filter combined with the finite element model has grown up and projects its potential for complex rotor systems. This paper investigates the application of the augmented Kalman filter (AKF) to a practical turbofan engine. The current study reveals that using steady-state responses as measurements can cause fluctuation in the estimated results, even divergence for some cases, while the available signals in practice are steady-state responses generally. To the authors' knowledge, this practical problem is revealed for the first time. To address the problem, the convergence criterion is employed to improve the AKF and formulates the adaptive fading augmented Kalman filter (AFAKF) proposed in this paper. Results indicate that the increase of the amplification factor, the insufficient measurement points, and the complexity of the dynamic model can all lead to the deterioration of the estimated unbalance. The proposed AFAKF method shows favorable convergence and can achieve accurate estimation with less than 5% relative errors, and the superiority over AKF in computation cost is also observed. [ABSTRACT FROM AUTHOR]

Bearing is the most vulnerable key part in rotating machine and bears important influence on the safety of equipment. Weakness and complexity are the two features of fault characteristic information carried by signals in the early stage of fault. For that, a fault is difficult to be recognized correctly. To identify a compound failure of bearing, the paper has brought forward a new self-adaptive option method for component signals that are sensitive to failure feature information of bearing. The sensitivity of kurtosis to bearing failure is exploited and the influence of signal complexity on the extraction of failure feature information is taken seriously, the paper has proposed the self-adaptive option method for component signals that are sensitive to failure feature by combined kurtosis with Complexity parameter included in Hjorth parameters. Furthermore, as the mid-value represents the general level of signal and is not affected by larger or smaller data, with the mid-values of kurtosis and Complexity parameter as the boundary, the paper has chosen the component signals which can more comprehensively show the failure features of bearing. Additionally, by principal component analysis (PCA), component signals selected are blended and reconstructed. Finally, by the Hilbert envelope spectrum of signals reconstructed, failure types of bearing are identified. To verify the effectiveness of presented method, the presented method is compared with conventional method on the basis of the exactly consistent data. The result indicates that the proposed method is superior to the traditional one in extracting fault information and identifying the multiple failure types of bearing. [ABSTRACT FROM AUTHOR]

The article presents a calendar of forthcoming congresses and conventions. The 13th International Congress on Sound and Vibration will be held on July 2-6, 2006 at Vienna University of Technology in Vienna, Austria. The 16th European Conference of Fracture will be held on July 3-7, 2006 in Alexandroupolis, Greece. The 8th Biennial ASME Conference on Engineering Systems Design and Analysis is scheduled on July 4-7, 2006 in Politecnico di Torino, Torino, Italy.

The article presents calendar of events related to mechanical engineering for 2006. The 19th International Congress & Exhibition on Condition Monitoring and Diagnostic Engineering Management will be on June 12 and 15. The 10th International Conference on Electrorheological Fluids and Magnetorheological Suspensions will take place in June 18 to 22. The 7th International Conference on Vibration Measurements by Laser Techniques-Advances and Applications & Short Course. The 13th International Congress on Sound and Vibration will be on July 2 to 6. The 16th European Conference on Fracture will be on July 3 to 7.

Environmental enrichment, besides having a great impact on animal welfare, can also be a potential variable in experimental research. Thus, we investigated whether enrichment of cages with paper tissues or plastic tunnels affects scientific outcome in the well-described mouse model of allergic asthma. BALB/cJ mice were introduced to paper tissues as nesting material, transparent plastic tunnels serving as shelters or kept in non-enriched cages. Afterwards, mice were sensitized to chicken egg ovalbumin (OVA) precipitated in aluminium sulphate and then intranasally challenged with OVA to induce allergic lung inflammation. Mice housed in cages enriched with paper tissues, but not with plastic tunnels, had increased total cell number, eosinophil number and IL-13 concentration in bronchoalveolar lavage fluid in comparison with the non-enriched control group. These results indicate that the effect of environmental enrichment on mice asthma models depends on the type of enrichment used. Therefore, it is important to consider the potential effects of any environmental enrichment on animal welfare and more importantly, on research results in order to standardize and obtain more accurate data from rodent studies. [ABSTRACT FROM AUTHOR]

This paper proposes a new disturbance observer concept based on the information of the estimated and measured signals for a micro-electro-mechanical system. First, the sliding-mode observer based on the linear matrix inequality was designed to estimate the states of a micro-electro-mechanical system gyroscope. Second, a new disturbance observer was proposed for estimating perturbations of the T-S fuzzy micro-electro-mechanical system gyroscope. Third, the double phase's fixedtime sliding-mode control was designed to control the positions and velocities of the MEMS system. The proposed disturbance observer input signals were taken into account from the measured and estimated signals. Two cases of high magnitudes and high frequencies disturbances were used to test the power of the proposed disturbance observer. Fourth, the Lyapunov condition was used to verify the corrections of the proposed controller and observer. Finally, the simulation by using MATLAB software was used to show the power of the proposed methods. The achievements of the small reachingtime, small tracking error, and stable steady-states under the vibration form outside of the system. [ABSTRACT FROM AUTHOR]

This paper contains the solution to the problem of a semi-infinite moving crack situated in an orthotropic strip bonded between two identical strips. The crack moves with a constant velocity, and the surface is under shear wave disturbance. We first examine the equations of elasticity, which include equilibrium equations and stress and displacement constitutive relations with the model-specific continuity and boundary conditions. Using the Fourier integral transform, the standard form for the Wiener–Hopf (W-H) equation is obtained, which is solved using the W-H method. The analytical expressions for the considered crack problem have been obtained for stress intensity factor (SIF), normalized stress intensity factor (NSIF), and stress magnification factor (SMF). The behavior of NSIF has been graphically presented for particular cases of composite materials for different crack propagation velocities and various depth ratios of the strips. The novelty of this paper lies in the analytic solutions using the W-H method for the semi-infinite moving crack problem under the influence of anti-plane shear waves. The pictorial presentations of normalized SIF clearly show their dependency on strip depths, crack propagation velocities and elastic constants. [ABSTRACT FROM AUTHOR]

Periodic structures are a type of metamaterial in which the physical properties depend not only on the details of the unit cell but also on how unit cells are arranged and interact with each other. In conventional engineering structures, each unit cell interacts with adjacent cells. Methods developed for vibrational and wave propagation analysis in periodic engineering structures consider only nearest-neighbor interactions. The dispersion curves of such systems, in which only adjacent cells interact, have been extensively studied. Metamaterial properties depend on the interactions of a unit cell with other cells. Further interactions, and specifically, interactions beyond the closest neighbors, imply a more complex band structure and wave behavior. In this paper, an example class of such structures, in which electrostatic forces are the driving force, has been investigated. In this paper, properties affecting these periodic structures, such as elastic forces, have been investigated. An attractive property of such structures is that the band structures of such metamaterials can be tuned by changing electric voltages. [ABSTRACT FROM AUTHOR]

Control effects of leading-edge grooves on deep cavity noise are investigated numerically. The length-to-depth ratio of the grooves are 0.5, 1, and 4, respectively. The freestream Mach number is equal to 0.16, corresponding to the Re based on the cavity length of 7.7 × 105. The Detached Eddy Simulations (DES) combined with Ffowcs Williams–Hawkings (FW-H) acoustic analogy are adopted to simulate the characteristic information of the flow field and the acoustic field. The analysis results show that all grooves investigated in this paper have a certain noise control effect, and the groove with the most obvious noise reduction effect is the groove with a length-to-depth ratio of 0.5, namely, the deep groove. Narrowband noise generated by the flow-acoustic feedback (100–700 Hz) and the acoustic resonance mechanism (above 300 Hz) and broadband noise caused by the turbulent disturbance in the shear layer of the cavity mouth significantly reduce when the deep groove is used for the noise control. The reason for the noise reduction is that the leading-edge grooves can effectively change the flow characteristics near the mouth of the downstream cavity. When the flow passes the grooves, the groove flow reduces the energy in the fluid, resulting in the significant decrease of flow velocity of the boundary layer of the incoming flow of the cavity. In addition, the use of the deep groove also promotes the vortex concentration position to move towards the bottom of the cavity, pushes the energy in the shear layer of the downstream cavity towards the front-edge as well as the bottom of the cavity, and stabilizes the development of the shear layer near the cavity mouth. [ABSTRACT FROM AUTHOR]

In the active magnetic bearing (AMB)-rotor system, a displacement sensor is one of the indispensable components. It detects the displacement of the rotor in real time and feeds back to the control system to realize the stable suspension of the rotor. However, due to electromagnetic interference, unstable power supply, poor grounding, and uneven rotor surface, the signal runout of the displacement sensor can often occur, resulting in rotor vibration. Given the above problems, this paper establishes the control model of the AMB-rotor system, lists three typical sensor runout signals, then analyzes the influence of different types of sensor runout on the system, and discusses the control methods under different sensor runout conditions. The research results have a specific guiding significance for vibration control of the maglev rotor under sensor runout influence. [ABSTRACT FROM AUTHOR]

Free vibration characteristics in uniform beams with several lumped attachments are an important problem in engineering applications that have to deal with mounting different equipment (e.g. motors, oscillators or engines) on a structural beam. In order to solve the lack of a generalized automatic procedure, this investigation presents a simple solving approach based on analytical means applied to a secular frequency equation for obtaining the natural frequencies of an arbitrarily supported single-span, or multi-span Euler–Bernoulli beam carrying any combination of miscellaneous attachments. The approach is obtained by solving a characteristic polynomial equation using a classical method for computing the roots of a polynomial. Interestingly, if the number of elements is greater than one, a pole-zero cancellation is needed, but it does not require manual interventions such as initial values and iteration. The mathematical approach is validated with bibliographic references and evaluated for accuracy and computational effectiveness. A good agreement is observed with relative error values practically negligible mostly ranging between 10−3 and 10−9 in the first five natural frequencies, which confirms the validity of the presented approach in this paper. The MatLab code that has been developed with the solving approach is freely available as a supplementary material to this paper. Additionally, a MatLab graphical user interface has also been developed in this work which allows to obtain the eigenvalues of a simply supported Euler–Bernoulli beam carrying an undetermined number of lumped elements. The graphical user interface is also available for download, along with help facilities to be run in a Windows operating system and detailed instructions to reproduce the case studies presented here. The proposed scheme (and also the MatLab graphical user interface) is very easy to code, and can be slightly modified to accommodate beams with arbitrary supports. [ABSTRACT FROM AUTHOR]

For a given class of materials, universal displacements are those displacements that can be maintained for any member of the class by applying only boundary tractions. In this paper, we study universal displacements in compressible anisotropic linear elastic solids reinforced by a family of inextensible fibers. For each symmetry class and for a uniform distribution of straight fibers respecting the corresponding symmetry, we characterize the respective universal displacements. A goal of this paper is to investigate how an internal constraint affects the set of universal displacements. We have observed that other than the triclinic and cubic solids in the other five classes (a fiber-reinforced solid with straight fibers cannot be isotropic), the presence of inextensible fibers enlarges the set of universal displacements. [ABSTRACT FROM AUTHOR]

This paper studies the continuous-time behavior of sampled-data control systems. In these systems, a discrete-time control law is applied to a continuous-time system model using sampling and zero-order hold. Traditionally, sampled-data systems are modeled in discrete-time, and thus, the intersample dynamics cannot be examined. This paper shows that the classical methods (such as the d2c function of MATLAB) for obtaining continuous-time models can be inaccurate between the sampling instants, even when Shannon's sampling theorem is satisfied. In this paper, a new method is also presented which can be used to characterize the continuous-time dynamics of sampled-data control systems. The new continuous-time system model including the intersample behavior is derived analytically from the discrete-time model, and the results are verified by simulations. [ABSTRACT FROM AUTHOR]

A static world assumption is often used when considering the simultaneous localization and mapping (SLAM) problem. In reality, especially when long-term autonomy is the objective, this is not a valid assumption. This paper studies a scenario where landmarks can occupy multiple discrete positions at different points in time, where each possible position is added to a multi-hypothesis map representation. A selector-mixture distribution is introduced and used in the observation model. Each landmark position hypothesis is associated with one component in the mixture. The landmark movements are modeled by a discrete Markov chain and the Monte Carlo tree search algorithm is suggested to be used as component selector. The non-static environment model is further incorporated into the factor graph formulation of the SLAM problem and is solved by iterating between estimating discrete variables with a component selector and optimizing continuous variables with an efficient state-of-the-art nonlinear least squares SLAM solver. The proposed non-static SLAM system is validated in numerical simulation and with a publicly available dataset by showing that a non-static environment can successfully be navigated. [ABSTRACT FROM AUTHOR]

A comprehensive collection of papers citing the works of a leading theoretical molecular spectroscopist has been analyzed. Citations were collected in the period 1937-75, and classified by the following criteria: (a) cited in a 'cover-all' review; (b) cited among others; (c) cited extensively or as argumentation; (d) cited with some reservation; (e) cited with criticism; and (f) extensively used for further development. Results indicate a constant citation frequency within the entire period studied. It seems that the effect of the increase of publication output in this field is just about compensated for by the decay of the citation frequency. Citations of type a are uniformly spread over all papers, with an average of one citation every ten years. The ratio of types a + b to types c + d + e + f is not inconsistent with a value of about 1:2 - that is, citations to this author reflect considerable real impact. [ABSTRACT FROM AUTHOR]

Honeycomb paperboard has been widely used in transportation and packaging of electronic instruments and furniture owing to the advantages of light weight, good compression resistance, environmental friendliness, and easy degradation. As a common cushioning material in transportation, it is worth studying the damping characteristic and vibration reduction mechanism of honeycomb paperboard. Based on the basic principles of vibration mechanics, the damping of honeycomb paperboard was proposed. Then the influences of cell length, paperboard thickness, grammage of core paper, and the honeycomb structures with face sheet or without face sheet on the damping characteristic of honeycomb paperboard were analyzed. Finally, the vibration reduction mechanism of packaging system with honeycomb paperboard and block was discussed briefly. The results show that the damping value of honeycomb paperboard decreases with the increase of cell length and paperboard thickness. The honeycomb paperboard with large grammage of core paper has high damping value, and yet paper honeycomb core structure without face sheet has poor damping capacity. What's more, the vibration reduction capacity of packaging system is influenced by the deformation and damping characteristic of honeycomb paperboard, among which material damping and structural damping contribute more, honeycomb deformation and air damping contribute less. The weight of block does not affect the damping characteristic of honeycomb paperboard, but affects the vibration reduction capacity of the whole system. [ABSTRACT FROM AUTHOR]

In recent decades, there has been a growing interest in cognitive science in the philosophical and scientific study of embodied, embedded, extended and enactive cognition, the so-called "4E cognition". The purpose of this special issue is to highlight the research on 4E cognition in one of these regions, Chile. In this special issue we intend, first, to map the current state of research on 4E cognition in Chile, and second, to critically examine the theoretical and philosophical challenges and possibilities that such a research poses. [Extracted from the article]

Presents an introduction to May 1, 2005 issue of "The International Journal of High Performance Computing Applications."

Computational biology allows and encourages the application of many different parallelism-based technologies. This special issue brings together high-quality state-of-the-art contributions about parallelism-based technologies in computational biology, from different points of view or perspectives, that is, from diverse high-performance computing applications. The special issue collects considerably extended and improved versions of the best papers, accepted and presented in PBio 2015 (the Third International Workshop on Parallelism in Bioinformatics, and part of IEEE ISPA 2015). The domains and topics covered in these seven papers are timely and important, and the authors have done an excellent job of presenting the material. [ABSTRACT FROM AUTHOR]

Citation counts are central to many studies in the sociology of science. Due to cost considerations and the format of the Science Citation Index, researchers often collect citations only to a scientist's first-authored publications (so called 'straight counts'), rather than to complete counts based on all published papers. This paper examines the consequences of using straight counts to study the careers of a sample of PhD biochemists. It is found that even though these two measures are highly correlated, there is a significant chance of making substantive errors when straight counts are substituted for complete counts. The problem is found to be more severe when citations are the dependent variable rather than an independent variable. It is argued that our findings can be generalized to other fields where multiple authorship is common. Accordingly, extreme care must be used in interpreting results based on straight citation counts. [ABSTRACT FROM AUTHOR]