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Direct damage-controlled design of plane steel moment-resisting frames using static inelastic analysis
Get PDFA new direct damage-controlled design method for plane steel frames under static loading is presented. Seismic loading can be handled statically in the framework of a push-over analysis. This method, in contrast to existing steel design methods, is capable of directly controlling damage, both local and global, by incorporating continuum damage mechanics for ductile materials in the analysis. The design process is accomplished with the aid of a two-dimensional finite element program, which takes into account material and geometric nonlinearities by using a nonlinear stress-strain relation through the beam-column fiber modeling and including P-δ and P-Δ effects, respectively. Simple expressions relating damage to the plastic hinge rotation of member sections and the interstorey drift ratio for three performance limit states are derived by conducting extensive parametric studies involving plane steel moment-resisting frames under static loading. Thus, a quantitative damage scale for design purposes is established. Using the proposed design method one can either determine damage for a given structure and loading, or dimension a structure for a target damage and given loading, or determine the maximum loading for a given structure and a target damage level. Several numerical examples serve to illustrate the proposed design method and demonstrate its advantages in practical applications
Dynamic vehicle routing problems: Three decades and counting
No full textSince the late 70s, much research activity has taken place on the class of dynamic vehicle routing problems (DVRP), with the time period after year 2000 witnessing a real explosion in related papers. Our paper sheds more light into work in this area over more than 3 decades by developing a taxonomy of DVRP papers according to 11 criteria. These are (1) type of problem, (2) logistical context, (3) transportation mode, (4) objective function, (5) fleet size, (6) time constraints, (7) vehicle capacity constraints, (8) the ability to reject customers, (9) the nature of the dynamic element, (10) the nature of the stochasticity (if any), and (11) the solution method. We comment on technological vis-à-vis methodological advances for this class of problems and suggest directions for further research. The latter include alternative objective functions, vehicle speed as decision variable, more explicit linkages of methodology to technological advances and analysis of worst case or average case performance of heuristics.© 2015 Wiley Periodicals, Inc
A minimum dataset for a standard adult transthoracic echocardiogram: a guideline protocol from the British Society of Echocardiography.
No full textThere have been significant advances in the field of echocardiography with the introduction of a number of new techniques into standard clinical practice. Consequently, a 'standard' echocardiographic examination has evolved to become a more detailed and time-consuming examination that requires a high level of expertise. This Guideline produced by the British Society of Echocardiography (BSE) Education Committee aims to provide a minimum dataset that should be obtained in a comprehensive standard echocardiogram. In addition, the layout proposes a recommended sequence in which to acquire the images. If abnormal pathology is detected, additional views and measurements should be obtained with reference to other BSE protocols when appropriate. Adherence to these recommendations will promote an increased quality of echocardiography and facilitate accurate comparison of studies performed either by different operators or at different departments
THE REDMAPPER GALAXY CLUSTER CATALOG FROM DES SCIENCE VERIFICATION DATA
No full textWe describe updates to the redMaPPer algorithm, a photometric red-sequence cluster finder specifically designed for large photometric surveys. The updated algorithm is applied to 150 deg2 of Science Verification (SV) data from the Dark Energy Survey (DES), and to the Sloan Digital Sky Survey (SDSS) DR8 photometric data set. The DES SV catalog is locally volume limited and contains 786 clusters with richness l > 20 (roughly equivalent to M500c ≳ 1014 h70-1 M⊙) and 0.2 < z < 0.9. The DR8 catalog consists of 26,311 clusters with 0.08 < z < 0.6, with a sharply increasing richness threshold as a function of redshift for z ≳ 0.35. The photometric redshift performance of both catalogs is shown to be excellent, with photometric redshift uncertainties controlled at the σz (1 + z) ∼ 0.01 level for z ≲ 0.7, rising to ∼0.02 at z ∼ 0.9 in DES SV. We make use of Chandra and XMM X-ray and South Pole Telescope SunyaevZeldovich data to show that the centering performance and mass-richness scatter are consistent with expectations based on prior runs of redMaPPer on SDSS data. We also show how the redMaPPer photo-z and richness estimates are relatively insensitive to imperfect star/galaxy separation and small-scale star masks. © 2016. The American Astronomical Society. All rights reserved
Sponsorship of Grassroots Sport: a Scoping Review of Research
No full textGrassroots sport is under increasing financial pressure with sponsorship providing a key income stream. This paper offers the first scoping review on the management of grassroots sponsorship, determining the state of research in this area to provide suggestions for further scholarly attention. Searching literature up until 2020 using terms including grassroots sport and sponsorship, 18 articles were returned, with descriptive then thematic analysis being undertaken. The review reports that studies are being conducted in economically leading countries, tending to focus on events and, to lesser extents, sport properties. Eight themes were constructed encompassing the securing, maintaining, and use of sponsorship, and grouped into two categories: (i) pre-sponsorship, and (ii) during sponsorship activity. Study in this area was stressed as being still in its infancy and largely atheoretical, with this paper serving to facilitate further conversation and investigation into the managerial practices associated with grassroots sport sponsorship
A study on the relative accuracy and robustness of the convolutional recurrent neural network based approach to binaural sound source localisation
Get PDFBinaural sound source localization is the task of finding the location of a sound source using binaural audio as affected by the head-related transfer functions (HRTFs) of a binaural array. The most common approach to this is to train a convolutional neural network directly on the magnitude and phase of the binaural audio. Recurrent layers can then also be introduced to allow for consideration of the temporal context of the binaural data, as to create a convolutional recurrent neural network (CRNN). This work compares the relative performance of this approach for speech localization on the horizontal plane using four different CRNN models based on different types of recurrent layers; Conv-GRU, Conv-BiGRU, Conv-LSTM, and Conv-BiLSTM, as well as a baseline system of a more conventional CNN with no recurrent layers. These systems were trained and tested on datasets of binaural audio created by convolution of speech samples with BRIRs of 120 rooms, for 50 azimuthal directions. Additive noise created from additional sound sources on the horizontal plane were also added to the signal. Results show a clear preference for use of CRNN over CNN, with overall localization error and front-back confusion being reduced, with it additionally being seen that such systems are less effected by increasing reverb time and reduced signal to noise ratio. Comparing the recurrent layers also reveals that LSTM based layers see the best overall localisation performance, while layers with bidirectionality are more robust, and so overall finding a preference for Conv-BiLSTM for the task
Gambling harms, stigmatisation and discrimination: A qualitative naturalistic forum analysis
Get PDFPeople who experience gambling harms commonly experience stigmatisation, which is detrimental to psychological wellbeing, and a significant barrier to help-seeking. While there have been efforts to challenge stigmatisation, there is little empirical evidence available to inform such initiatives. To address this gap in knowledge, we conducted a thematic analysis of naturalistic data in the form of posts made on online support forums by people with experience of gambling-related harm, in order to understand how they are stigmatised, and to identify barriers to help-seeking. Five main themes were identified: (a) beliefs about the nature and origin of gambling addiction, which related to participants’ beliefs about causes of gambling harm and cognitions about the nature of addiction; (b) self-stigma, which encompassed the frequent and substantial incidences of self-stigma; (c) anticipated stigma, which described the stigma and discrimination people expected to face because of their gambling harm; (d) stigmatising other people who experience gambling harm, which describes the ways in which some people who experienced gambling harms stigmatised other people who experienced gambling harms; and (e) experienced stigma and discrimination, which encompassed the experienced stigmatisation people encountered. Experiences discussed/described within the forums were developed into a timeline of gambling harms which was cyclical in nature and involved six stages: onset, concealment of problems, crisis point, disclosure of problems, recurrence of harms (sometimes termed ‘relapse’) and recovery. The study highlights the impact of societal stigma on individuals’ self-perception and interactions, particularly emphasising the challenges experienced during relapse periods, which heighten stigma and distress. The study also identifies potential avenues for stigma reduction, including targeted campaigns addressing societal, anticipated, and self-stigma
Finite-Time H∞ State Estimation for Markovian Jump Neural Networks with Time-Varying Delays via an Extended Wirtinger’s Integral Inequality
Get PDFThis study investigates the finite-time boundedness for Markovian jump neural networks (MJNNs) with time-varying delays. An MJNN consists of a limited number of jumping modes wherein it can jump starting with one mode then onto the next by following a Markovian process with known transition probabilities. By constructing new Lyapunov–Krasovskii functional (LKF) candidates, extended Wirtinger’s, and Wirtinger’s double inequality with multiple integral terms and using activation function conditions, several sufficient conditions for Markovian jumping neural networks are derived. Furthermore, delay-dependent adequate conditions on guaranteeing the closed-loop system which are stochastically finite-time bounded (SFTB) with the prescribed H∞ performance level are proposed. Linear matrix inequalities are utilized to obtain analysis results. The purpose is to obtain less conservative conditions on finite-time H∞ performance for Markovian jump neural networks with time-varying delay. Eventually, simulation examples are provided to illustrate the validity of the addressed method
Hybrid Cyber-Security Model for Attacks Detection Based on Deep and Machine Learning
Get PDFNowadays, numerous attacks can be considered high risks in terms of the security of Wireless Sensor Networks (WSN). As a result, different applications are introduced to manage the data and information exchange and related security sides to be save in transmission of data. Recently, most of the security attacks are classified as cyber ones. These attacks interest in the system halting and destroying the data rather than stealing the data. In this paper, a cyber-attacks detection system is proposed based on an intelligent hybrid model that uses deep and machine learning technologies. The proposed model improves the cyber-attack detection speed. In addition, a feature reduction model is proposed using machine learning methods (PCA and SVD) to select the most related features to the adopted classes of attacks. This can positively affect the deep-learning model complexity. The obtained results demonstrate the superiority of the proposed hybrid model-based cyber detection system in comparison to the traditional ones in reaching an accuracy of 99.98%, 100%, 100%, 100% for precision, recall, and F1-measure respectively, and reducing the time to 23s for the datasets of Message Queuing Telemetry Transport-Dataset (MQTT-DS) and Wireless Sensor Networks Dataset (WSN-DS)
Light pollution at night: using the ‘windscreen wiper’ technique to maintain a proper lookout at night
Get PDFLast year, the authors published an article highlighting the issues watchkeepers face when maintaining a proper lookout during the day (‘Scanning: From screen to screen’, Seaways November 2022). This article takes the same topic further, exploring the issues faced at night together with suggestions to improve the ability to maintain lookout in the darkness. This research is part of a project funded by Maritime Research and Innovation UK (MarRI-UK) studying Lookout Awareness of Distractions. A key part of this project is the creation of a Distraction Evaluation Ratio (LADDER)
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