Extracting Useful Information from Social Media during Disaster Events

In recent years, social media platforms such as Twitter and Facebook have emerged as effective tools for broadcasting messages worldwide during disaster events. With millions of messages posted through these services during such events, it has become imperative to identify valuable information that can help the emergency responders to develop effective relief efforts and aid victims. Many studies implied that the role of social media during disasters is invaluable and can be incorporated into emergency decision-making process. However, due to the "big data" nature of social media, it is very labor-intensive to employ human resources to sift through social media posts and categorize/classify them as useful information. Hence, there is a growing need for machine intelligence to automate the process of extracting useful information from the social media data during disaster events. This dissertation addresses the following questions: In a social media stream of messages, what is the useful information to be extracted that can help emergency response organizations to become more situationally aware during and following a disaster? What are the features (or patterns) that can contribute to automatically identifying messages that are useful during disasters? We explored a wide variety of features in conjunction with supervised learning algorithms to automatically identify messages that are useful during disaster events. The feature design includes sentiment features to extract the geo-mapped sentiment expressed in tweets, as well as tweet-content and user detail features to predict the likelihood of the information contained in a tweet to be quickly spread in the network. Further experimentation is carried out to see how these features help in identifying the informative tweets and filter out those tweets that are conversational in nature

A Transformer-Based Substitute Recommendation Model Incorporating Weakly Supervised Customer Behavior Data

The substitute-based recommendation is widely used in E-commerce to provide better alternatives to customers. However, existing research typically uses the customer behavior signals like co-view and view-but-purchase-another to capture the substitute relationship. Despite its intuitive soundness, we find that such an approach might ignore the functionality and characteristics of products. In this paper, we adapt substitute recommendation into language matching problem by taking product title description as model input to consider product functionality. We design a new transformation method to de-noise the signals derived from production data. In addition, we consider multilingual support from the engineering point of view. Our proposed end-to-end transformer-based model achieves both successes from offline and online experiments. The proposed model has been deployed in a large-scale E-commerce website for 11 marketplaces in 6 languages. Our proposed model is demonstrated to increase revenue by 19% based on an online A/B experiment.Comment: 6 pages, 3 figures, 5 tables, accepted in 21st IEEE International Conference on Machine Learning and Application

Novel design of a soft lightweight pneumatic continuum robot arm with decoupled variable stiffness and positioning

Soft robot arms possess unique capabilities when it comes to adaptability, flexibility and dexterity. In addition, soft systems that are pneumatically actuated can claim high power to weight ratio. One of the main drawbacks of pneumatically actuated soft arms is that their stiffness cannot be varied independently from their end-effector position in space. The novel robot arm physical design presented in this paper successfully decouples its end-effector positioning from its stiffness. An experimental characterisation of this ability is coupled with a mathematical analysis. The arm combines the light weight, high payload to weight ratio and robustness of pneumatic actuation with the adaptability and versatility of variable stiffness. Light weight is a vital component of the inherent safety approach to physical human-robot interaction. In order to characterise the arm, a neural network analysis of the curvature of the arm for different input pressures is performed. The curvature-pressure relationship is also characterised experimentally

Surface tailored PS/TiO2 composite nanofiber membrane for copper removal from water

none8siPolystyrene (PS)/TiO2 composite nanofiber membranes have been fabricated by electrospinning process for Cu2+ ions removal from water. The surface properties of the polystyrene nanofibers were modulated by introducing TiO2 nanoparticles. The contact angle of the PS nanofiber membrane was found to be decreased with increasing concentration of TiO2, depicted enhanced hydrophilicity. These membranes were highly effective in adsorbing Cu2+ ions from water. The adsorption capacity of these membranes was found to be 522 mg/g, which is significantly higher than the results reported by other researchers.This was attributed to enhanced hydrophilicity of the PS/TiO2 composite nanofiber membranes and effective adsorption property of TiO2 nanoparticles.noneWanjale, Santosh; Birajdar, Mallinath; Jog, Jyoti; Neppalli, Ramesh; Causin, Valerio; Karger-Kocsis, József; Lee, Jonghwi; Panzade, PrasadWanjale, Santosh; Birajdar, Mallinath; Jog, Jyoti; Neppalli, Ramesh; Causin, Valerio; Karger Kocsis, József; Lee, Jonghwi; Panzade, Prasa

Recent Progress in Electrospun Nanofibres: Reinforcement Effect and Mechanical Performance

Composite materials are becoming increasingly important as structural materials for aeronautical and space engineering, naval, automotive, and civil engineering, sporting goods, and other consumer products. Fiber-based reinforcement represents one of the most effective manufacturing strategies for enhancing the mechanical strength and other properties of composite materials. Electrospinning has gained widespread interest in the last two decades because of its ability to fabricate continuous ultrafine nanofibers with unique characteristics. The impact of electrospinning on fiber synthesis and processing, characterization, and applications in drug delivery, nanofiltration, tissue scaffolding, and electronics has been extensively studied in the past. In this article, the authors have focused on a comprehensive review of the mechanical performance and properties of electrospun nanofibers as potential reinforcements as well as their advanced nanocomposites

Design, fabrication and control of soft robots

Conventionally, engineers have employed rigid materials to fabricate precise, predictable robotic systems, which are easily modelled as rigid members connected at discrete joints. Natural systems, however, often match or exceed the performance of robotic systems with deformable bodies. Cephalopods, for example, achieve amazing feats of manipulation and locomotion without a skeleton; even vertebrates such as humans achieve dynamic gaits by storing elastic energy in their compliant bones and soft tissues. Inspired by nature, engineers have begun to explore the design and control of soft-bodied robots composed of compliant materials. This Review discusses recent developments in the emerging field of soft robotics.National Science Foundation (U.S.) (Grant IIS-1226883

Study on structure and morphology of polymer nanocomposites

The reinforcement of polymers using fillers, whether inorganic or organic, is common in modern plastics. Polymer nanocomposites or, with a more inclusive term, polymer nanostructured materials, represent a radical alternative to these traditional filled polymer compositions. In contrast to ordinary polymer systems where reinforcement is on the order of microns, polymer nanocomposites are exemplified by discrete constituents on the order of a few nanometers. In the past decade polymer/clay nanocomposites have emerged as a new class of materials and attracted considerable interest in research and development worldwide after initial reports from the Toyota group on Nylon 6 / clay nanocomposites. Enormous amount of work has been done on preparation and characterization of polymer/organoclay nanocomposites because by this approach it is possible to impart much improved mechanical, thermal, electrical properties with respect to their macro and micro counterparts. There are now many well-developed techniques that are used to produce conventional polymer blends and composites, and various products have been widely commercialized. There are also numerous papers, patents, books, and handbooks that introduce and discuss the development and application of various polymeric blends and composites. Over the past two decades, however, biodegradable/compatible polymers and polymers from renewable resources (PFRR) have been attracting increasing attention, primarily for two major reasons: environmental concerns, and the realization that our petroleum resources are finite. A third reason for the growing interest in polymers from renewable resources relates to adding value to agricultural products, which is economically important for many countries. The present thesis is organized and presented in seven chapters. A brief overview of polymer nanocomposites, of the different fillers used for the preparation polymer composites, and of the different matrices used for polymer nanocomposites are discussed in the first chapter. The scope and objectives of the thesis are described in the second chapter. In the third chapter, various characterization techniques used in this work such as wide angle X-ray diffraction (WAXD), small angle X-ray scattering (SAXS), optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Infrared spectroscopy (IR), differential scanning calorimetry (DSC), polarized light optical microscopy (PLOM), thermogravimetric analysis (TGA), etc. are described. The fourth chapter describes poly(ε-caprolactone) (PCL) based nanocomposites. For this, PCL was reinforced with different kinds of nanofillers such as clay nanoparticles and different types of electrospun nanofibers. The effect of those nanofillers on PCL matrix structure, morphology, tensile mechanical properties and degradation behavior was analyzed. The fifth chapter deals with poly(lactic acid) (PLA) based composites, in which PLA was reinforced with clay nanoparticles, electrospun nanofibers and also natural fibers. We tried to study the morphology, properties, and degradation behavior of these materials, etc. In the sixth chapter, the efficiency of particles filled electrospun nanofibers as reinforcement for poly(butylene succinate-co-adipate) (PBSA) was studied. Thus, the effect of those fibers on PBSA structure, morphology, and physical mechanical properties was elaborated. It was observed that by using this kind of nanofillers, it is possible to control the structural morphology of pristine polymer matrices and thus their mechanical properties and degradation behavior. Finally, in the seventh chapter, the general conclusions are given.Il rinforzo dei polimeri con cariche, sia organiche che inorganiche, è una comune strategia nella moderna industria delle materie plastiche. I nanocompositi polimerici, o secondo una definizione più ampia i materiali polimerici nanostrutturati, rappresentano una radicale alternativa alle tradizionali formulazioni dei compositi polimerici. Al contrario dei sistemi ordinari, in cui la carica è dell’ordine di grandezza dei micron, i nanocompositi polimerici contengono costituenti discreti di dimensioni nanometriche. A partire dal lavoro del gruppo della Toyota, nello scorso decennio, i nanocompositi polimerici con argilla sono emersi come una nuova classe di materiali che ha attratto l’interesse del mondo della ricerca e sviluppo sia accademico che industriale. Da allora è stata svolta un’enorme mole di lavoro riguardo la preparazione e la caratterizzazione di questo tipo di nanocompositi perché grazie a questo approccio è possibile impartire proprietà meccaniche, termiche ed elettriche molto migliori rispetto ai più comuni micro e macrocompositi. Oggi esistono molte tecniche sviluppate e mature per produrre compositi e blend polimerici convenzionali e sono stati posti in commercio moltissimi prodotti. Inoltre è disponibile un’ampia letteratura scientifica che introduce e discute gli sviluppi e le applicazioni di questi materiali. Negli ultimi due decenni, tuttavia, è cresciuto l’interesse per polimeri biodegradabili/biocompatibili e per polimeri da fonti rinnovabili, principalmente per due motivi: attenzione all’ambiente e la constatazione che le riserve di petrolio siano finite. Una terza ragione di interesse per i polimeri da fonti rinnovabili consiste nel valore aggiunto che tali materiali possono dare ai prodotti agricoli, un aspetto di grande interesse economico per molti paesi. Il presente lavoro di tesi è organizzato e presentato in sette capitoli. I nanocompositi polimerici saranno brevemente introdotti, assieme ai diversi additivi ed alle diverse matrici impiegate nei nanocompositi polimerici. Lo scopo e gli obiettivi della tesi sono descritti nel secondo capitolo. Nel terzo capitolo sono descritti i metodi usati per la caratterizzazione dei materiali, come la diffrazione dei raggi X ad alto angolo, la diffusione dei raggi X a basso angolo, la microscopia ottica, la microscopia elettronica a scansione, la microscopia elettronica in trasmissione, la spettroscopia infrarossa, la calorimetria differenziale a scansione, la microscopia ottica in luce polarizzata e la termogravimetria. Il quarto capitolo descrive i nanocompositi basati sul poli(ε-caprolattone) (PCL). Il PCL è stato rinforzato con diversi tipi di nanofiller come nanoparticelle di argilla e diversi tipi di nanofibre da elettrospinning. È stato analizzato l’effetto di questi nanofiller sulla struttura, sulla morfologia, sulle proprietà meccaniche e sul comportamento di degradazione del PCL. Il quinto capitolo presenta i risultati riguardanti i compositi dell’acido polilattico (PLA), nei quali il PLA è stato rinforzato con nanoparticelle di argilla, nanofibre da elettrospinning ed anche con fibre naturali. Anche in questo caso, abbiamo studiato approfonditamente struttura, morfologia e proprietà di questi materiali. Nel sesto capitolo, è stata studiata l’efficienza di nanofibre da elettrospinning caricate da particelle inorganiche come rinforzo per una matrice di poli(butilen succinato-co-adipato) (PBSA). È stato quindi investigato l’effetto di queste fibre sulla struttura, sulla morfologia e sulle proprietà del PBSA. Si è osservato che usando questo tipo di nanofiller è possibile controllare la morfologia e la struttura delle matrici polimeriche e quindi le loro proprietà meccaniche ed il loro comportamento di degradazione. Il settimo capitolo, infine, presenterà le conclusioni generali

Design, construction, inverse kinematics, and visualization of continuum robots

Continuum robots are the biologically inspired robots that mimic the behaviors of mammalian tongues, elephant trunks, and octopus arms. The drawbacks of two existing designs are examined and a new mechanical design that uses a single latex rubber tube as the central member is proposed, providing a design that is both simple and robust. Next, a novel verification procedure is applied to examine the validity of the proposed model in two different domains of applicability. A two-level electrical control scheme enables rapid prototyping and can be used to control the continuum robot remotely. Next, a new geometrical approach to solve inverse kinematics for continuum type robot manipulators is introduced. Given the tip of a three section robot, a complete inverse kinematics solution is obtained. Finally, the techniques involved in visualization of AirOctor/OctArm in 3D space in real-time are discussed. The algorithm has been tested with several system topologies

Arc fault protection for more electric aircraft application

In aircraft applications, arc faults can be hazardous and could lead to fire. Several recommendations have been made to improve aircraft wiring safety, including the development of arc fault circuit protection for wiring systems. This project focuses on developing an arc fault detection unit (hardware/software) to be included in a Solid-State Power Controller (SSPC) with the ability to differentiate between normal fault current and arc current with the immunity to normal load start-up transients. An arc detection evaluation board by Texas Instruments (TI) – RD 195 is analyzed and a corresponding MATLAB code is developed for the algorithm proposed by them. Firstly, to understand the working of the hardware analog circuits embedded on the board, they were simulated using SIMETRIX/LT-SPICE software and the respective output waveforms were captured. Also, these circuits were tested manually (hardware testing) by sending in a preset signal from signal generator and capturing the corresponding waveforms using oscilloscope. The hardware, software and calculated results were compared and tabulated for simplified understanding of the board. Secondly, a MATLAB code was developed for the given algorithm by TI with few enhancements to improve its sensitivity in distinguishing load transients and arcing cases. The developed MATLAB code is tested with several load current samples collected during arcing, no arcing and load transient scenarios. This report elaborates on the: 1. Arc generation circuit – The hardware setup used to generate arc and collect the current samples to be tested during arcing condition. 2. The hardware analysis of the TI RD-195 arc detection evaluation board. 3. Detailed flowchart of the arc detection algorithm used by TI. 4. Developing and testing of the MATLAB code representing the corresponding algorithm.Bachelor of Engineerin