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2018

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Articles 7621 - 7650 of 8951

Full-Text Articles in Engineering

Layer-To-Layer Physical Characteristics And Compression Behavior Of 3d Printed Acrylonitrile Butadiene Styrene Metastructures Fabricated Using Different Process Parameters, Sivani Patibandla Jan 2018

Layer-To-Layer Physical Characteristics And Compression Behavior Of 3d Printed Acrylonitrile Butadiene Styrene Metastructures Fabricated Using Different Process Parameters, Sivani Patibandla

Browse all Theses and Dissertations

Three-dimensional (3D) printing, a subset of additive manufacturing, is currently being explored heavily for actual part fabrication due to its ability to create complex objects with intricate internal features. There are several 3D printing technologies; however, the extrusion-based technology such as fused deposition modeling (FDM) is the widely used one owing to its low cost. The FDM method can be used to fabricate parts with different fill densities, fill patterns, and process parameters such as extruder temperature and print speed. In this research, influence of process parameters such as extruder temperature and speed on the physical characteristics such as the …


Multiple Drone Detection And Acoustic Scene Classification With Deep Learning, Hari Charan Vemula Jan 2018

Multiple Drone Detection And Acoustic Scene Classification With Deep Learning, Hari Charan Vemula

Browse all Theses and Dissertations

Classification of environmental scenes and detection of events in one's environment from audio signals enables one to create better-planning agents, intelligent navigation systems, pattern recognition systems, and audio surveillance systems. This thesis will explore the use of Convolutional Neural Networks(CNN'S) with spectrograms and raw audio waveforms as inputs to Deep Neural Networks with hand engineered features extracted from large-scale feature extraction schemes to identify the acoustic scenes and events. The first part focuses on building an audio pattern recognition system capable of detecting the if there are zero, one, or two DJI phantoms in the scene within the range of …


A Framework To Understand Emoji Meaning: Similarity And Sense Disambiguation Of Emoji Using Emojinet, Sanjaya Wijeratne Jan 2018

A Framework To Understand Emoji Meaning: Similarity And Sense Disambiguation Of Emoji Using Emojinet, Sanjaya Wijeratne

Browse all Theses and Dissertations

Pictographs, commonly referred to as `emoji’, have become a popular way to enhance electronic communications. They are an important component of the language used in social media. With their introduction in the late 1990’s, emoji have been widely used to enhance the sentiment, emotion, and sarcasm expressed in social media messages. They are equally popular across many social media sites including Facebook, Instagram, and Twitter. In 2015, Instagram reported that nearly half of the photo comments posted on Instagram contain emoji, and in the same year, Twitter reported that the `face with tears of joy’ emoji has been tweeted 6.6 …


Developing A Kinect Based Holoportation System, Soumya Chiday Jan 2018

Developing A Kinect Based Holoportation System, Soumya Chiday

Browse all Theses and Dissertations

Holographic communication and distributed collaboration offer great potential for empathic computing to help remove the cost, distance, language and expertise barriers in many social and economic activities. Recent advances in AR-enhanced communication as evident by Microsoft Holoportation technology demonstrate the progress toward fully immersive collaborations distributed and remotely. Current holoportation system requires the use of extensive camera-arrays and powerful server system due to the computation demand and sensory needs to capture and reconstruct the subject of interests Thus, they suffer in mobility and applicability in real-world scenarios. In this thesis, we present an ultra-portable holoportation system design that requires only …


Using Natural Language Processing And Machine Learning For Analyzing Clinical Notes In Sickle Cell Disease Patients, Shufa Khizra Jan 2018

Using Natural Language Processing And Machine Learning For Analyzing Clinical Notes In Sickle Cell Disease Patients, Shufa Khizra

Browse all Theses and Dissertations

Sickle Cell Disease (SCD) is a hereditary disorder in red blood cells that can lead to excruciating pain episodes. SCD causes the normal red blood cells to distort its shape and turn into sickle shape. The distorted shape makes the hemoglobin inflexible and stick to the walls of the vessels thereby obstructing the free flow of blood and eventually making the tissues suffer from lack of oxygen. The lack of oxygen causes serious problems including Acute Chest Syndrome (ACS), stroke, infection, organ damage, and over the lifetime an SCD can harm a persons spleen, brain, kidneys, eyes, bones. Sickling of …


Display And Analysis Of Tomographic Reconstructions Of Multiple Synthetic Aperture Ladar (Sal) Images, Bassirou Seck Jan 2018

Display And Analysis Of Tomographic Reconstructions Of Multiple Synthetic Aperture Ladar (Sal) Images, Bassirou Seck

Browse all Theses and Dissertations

Synthetic aperture ladar (SAL) is similar to synthetic aperture radar (SAR) in that it can create range/cross-range slant plane images of the illuminated scatters; however, SAL has wavelengths 10,000x smaller than SAR enabling a relatively narrow real aperture, diffraction limited beam widths. The relatively narrow real aperture resolutions allow for multiple slant planes to be created for a single target with reasonable range/aperture combinations. These multiple slant planes can be projected into a single slant plane projections (as in SAR). It can also be displayed as a 3-D image with asymmetric resolutions, diffraction limited in the dimension orthogonal to the …


Exploring Feedback Modalities Using Wearable Device For Complex Systems Training Programs, Layla Akilan Jan 2018

Exploring Feedback Modalities Using Wearable Device For Complex Systems Training Programs, Layla Akilan

Browse all Theses and Dissertations

This study examined the effectiveness of a wearable device in delivering various feedback modalities in an attempt to improve performance outcomes in complex systems. Secondarily this study looked at performance when feedback type was matched to preferred learning style according to VARK Learning Styles Inventory results. Participants were required to perform system monitoring and correct for system failures through key presses. Feedback was delivered through a smart watch and was based on response time performance. Feedback modalities included visual, auditory, and haptic feedback. Subjective ratings of situation awareness and mental workload were also examined. Results indicated that auditory feedback condition …


Constitutive Modeling Of Creep In Leaded And Lead-Free Solder Alloys Using Constant Strain Rate Tensile Testing, Eric Thomas Stang Jan 2018

Constitutive Modeling Of Creep In Leaded And Lead-Free Solder Alloys Using Constant Strain Rate Tensile Testing, Eric Thomas Stang

Browse all Theses and Dissertations

Environmental and safety concerns have necessitated a phase-out of lead-based alloys, which are often used in electronics solder applications. In order to properly assess suitable replacement materials, it is necessary to understand the deformation mechanisms relevant to the application. In the case of electronics solder, creep is an important mechanism that must be considered in the design of reliable devices and systems. In this study, Power-Law and Garofalo constitutive creep models were derived for two medium temperature solder alloys. The first alloy is known by the commercial name Indalloy 236 and is a quaternary alloy of lead, antimony, tin, and …


Novel Auto-Calibrating Neural Motor Decoder For Robust Prosthetic Control, Andrew Earl Montgomery Jan 2018

Novel Auto-Calibrating Neural Motor Decoder For Robust Prosthetic Control, Andrew Earl Montgomery

Browse all Theses and Dissertations

The overarching goal of this project is to develop novel neural motor decoders for prosthetic control. EMG decoders measure the activity from an intact but non-target muscle. Neural motor decoders transform the signal measured from the severed motor axons of the target muscle. A multi-scale, highly-realistic computer model of a spinal motor pool was developed (Allen & Elbasiouny, 2018) to serve as a computational platform for decoder development and testing. A firing rate-based algorithm was developed to transform the aggregate discharge of the motor pool into a command signal to control the simulated prosthetic MuJoCo hand. This algorithm was informed …


True-Average Current-Mode Control Of Dc-Dc Power Converters: Analysis, Design, And Characterization, Dalvir K. Saini Jan 2018

True-Average Current-Mode Control Of Dc-Dc Power Converters: Analysis, Design, And Characterization, Dalvir K. Saini

Browse all Theses and Dissertations

Energy efficient, wide-bandwidth, and well-regulated dc-dc power converters are in great demand in today's emerging technologies in areas such as medical, communication, aerospace, and automotive industries. In addition to design and selection of the converter components, a robust closed-loop modeling is very essential for reliable power-electronic systems. Two closed-loop control techniques for power converters exist: voltage-mode control and current-mode control. The principles of voltage-mode control have been explored in great depths by researchers over the last two decades. However, the dynamic modeling of current-mode controlled dc-dc power converters has many uncharted areas that needs careful attention. Two main methods exist …


Testing Of Recursive And Non-Recursive Algorithms For Real-Time Phasor And Frequency Estimations In Power Systems, Dhruv Sharma Jan 2018

Testing Of Recursive And Non-Recursive Algorithms For Real-Time Phasor And Frequency Estimations In Power Systems, Dhruv Sharma

Dissertations, Master's Theses and Master's Reports

Steady-state performance of various recursive and non-recursive algorithms are tested in this report according to the test signals given in the IEEE Standard C37.118.1-2011. Phase magnitude and phase angle of the power grid signals have been estimated using Discrete Fourier Transform (non-recursive), Discrete Fourier Transform (recursive), Least Square, and Wavelet Transform Algorithms. Frequency estimation is performed using Discrete Fourier Transform, Weighted Least Square, and Zero Crossing methods. These algorithms are evaluated in LabView software and tested by generating test signals in a Simulink model. Furthermore, Total Vector Error (TVE) is calculated using dynamic test signals as per the IEEE Standard …


Design And Evaluation Of Auditory-Supported Air Gesture Controls In Vehicles, Jason Sterkenburg Jan 2018

Design And Evaluation Of Auditory-Supported Air Gesture Controls In Vehicles, Jason Sterkenburg

Dissertations, Master's Theses and Master's Reports

The number of visual distraction-caused crashes highlights a need for non-visual information displays in vehicles. Auditory-supported air gesture controls could fill that need. This dissertation covers four experiments that aim to explore the design auditory-supported air gesture system and examine its real-world influence on driving performance. The first three experiments compared different prototype gesture control designs as participants used the systems in a driving simulator. The fourth experiment sought to answer more basic questions about how auditory displays influence performance in target acquisition tasks. Results from experiment 1 offered optimism for the potential of auditory-supported displays for navigating simple menus …


Probabilistic Regional Landslide Hazard Assessment For The Enguri Dam (Jivari, Georgia), Maria Diletta Acciaro Jan 2018

Probabilistic Regional Landslide Hazard Assessment For The Enguri Dam (Jivari, Georgia), Maria Diletta Acciaro

Dissertations, Master's Theses and Master's Reports

The Enguri Dam forms a reservoir in a seismically active area in the foothills of the Caucasus Mountain range near Jvari, Georgia. The slopes are steep, highly fractured, and weathered, which make them at risk to failure during or following extreme rainfall events. Hydroelectricity produced by the water retained by the 271-m dam provides almost half of the electricity for the country. The reservoir perimeter is more than 40 km and the surrounding slopes span an area of more than 30 km2. The size of the area and paucity of slope data have made slope-failure hazard assessment of the broader …


Design And Optimization Of An Electromagnetic Railgun, Nihar S. Brahmbhatt Jan 2018

Design And Optimization Of An Electromagnetic Railgun, Nihar S. Brahmbhatt

Dissertations, Master's Theses and Master's Reports

Railgun is a future weapon for shooting long-range targets with high accuracy. Railgun is an economical weapon as it does not use any kind of propellant for shooting a projectile. It uses high impulsive current to generate the necessary force required to hit the target. The US Navy has been planning to implement railgun system on ships as their long-range shooting weapon. Railgun needs to be charged up to a certain voltage level to generate the necessary force to shoot the projectile to achieve the specified target location. It is very important that minimal voltage is required for shooting the …


Analyzing The Life-Cycle Of Unstable Slopes Using Applied Remote Sensing Within An Asset Management Framework, El Hachemi Y. Bouali Jan 2018

Analyzing The Life-Cycle Of Unstable Slopes Using Applied Remote Sensing Within An Asset Management Framework, El Hachemi Y. Bouali

Dissertations, Master's Theses and Master's Reports

An asset management framework provides a methodology for monitoring and maintaining assets, which include anthropogenic infrastructure (e.g., dams, embankments, and retaining structures) and natural geological features (e.g., soil and rock slopes). It is imperative that these assets operate efficiently, effectively, safely, and at a high standard since many assets are located along transportation corridors (highways, railways, and waterways) and can cause severe damage if compromised. Assets built on or around regions prone to natural hazards are at an increased risk of deterioration and failure. The objective of this study is to utilize remote sensing techniques such as InSAR, LiDAR, and …


Viability Of Graywater Reuse In Lesotho’S Lowland Agricultural District, Ryan Wagner Jan 2018

Viability Of Graywater Reuse In Lesotho’S Lowland Agricultural District, Ryan Wagner

Dissertations, Master's Theses and Master's Reports

Water security has become a large issue with populations rising and weather patterns changing to drier and hotter conditions in southern Africa. Lesotho, a mountainous country landlocked by South Africa, is responsible for a large amount of the rainfall in southern Africa. As such, Lesotho provides water to South Africa in exchange for national economic growth. Lesotho, however, is also prone to droughts and with water reserves being sold to South Africa, water security has become a national issue. This study looked at Lesotho’s current water use habits and found that graywater reuse could lead to much more available water. …


Experimental Investigation Of Impinged Droplet Dynamics, Nitisha Ahuja Jan 2018

Experimental Investigation Of Impinged Droplet Dynamics, Nitisha Ahuja

Dissertations, Master's Theses and Master's Reports

The fuel spray wall interaction phenomenon plays an essential role in determining the emissions and performance of an internal combustion engine. The investigation of single droplet wall interaction is crucial to understanding of a spray wall impingement process. This report is a compilation of the experimental work done to understand the droplet impingement characteristics, through optical diagnostics and temperature measurement. Different fuels and different surface under ambient and elevated temperature conditions are used for these tests, with two objectives: Development of a common depositionsplashing criteria; and Understanding droplet post impingement dynamics variation with factors like: Weber number (ratio of inertia …


Target Detection, Tracking, And Localization Using Multi-Spectral Image Fusion And Rf Doppler Differentials, Casey D. Demars Jan 2018

Target Detection, Tracking, And Localization Using Multi-Spectral Image Fusion And Rf Doppler Differentials, Casey D. Demars

Dissertations, Master's Theses and Master's Reports

It is critical for defense and security applications to have a high probability of detection and low false alarm rate while operating over a wide variety of conditions. Sensor fusion, which is the the process of combining data from two or more sensors, has been utilized to improve the performance of a system by exploiting the strengths of each sensor. This dissertation presents algorithms to fuse multi-sensor data that improves system performance by increasing detection rates, lowering false alarms, and improving track performance. Furthermore, this dissertation presents a framework for comparing algorithm error for image registration which is a critical …


Reversibly Switching Adhesion Of Smart Adhesives Inspired By Mussel Adhesive Chemistry, Ameya R. Narkar Jan 2018

Reversibly Switching Adhesion Of Smart Adhesives Inspired By Mussel Adhesive Chemistry, Ameya R. Narkar

Dissertations, Master's Theses and Master's Reports

Catecholic groups in mussel adhesive proteins transition from being strongly adhesive in a reduced state under acidic conditions to being weakly adhesive in an oxidized state under basic conditions. Here, we exploit this pH responsive behavior of catechol and demonstrate that its oxidation state can be manipulated by incorporation of boronic acid to facilitate reversible transitions between strong and weak adhesion. Our first approach involved the addition of 3- acrylamido phenylboronic acid (APBA) to dopamine methacrylamide (DMA) containing adhesives. The synthesized adhesives showed strong adhesion to quartz surface in an acidic medium (pH 3), while weak adhesion was observed on …


Cyber-Based Contingency Analysis And Insurance Implications Of Power Grid, Zhiyuan Yang Jan 2018

Cyber-Based Contingency Analysis And Insurance Implications Of Power Grid, Zhiyuan Yang

Dissertations, Master's Theses and Master's Reports

Cybersecurity for power communication infrastructure is a serious subject that has been discussed for a decade since the first North American Electric Reliability Corporation (NERC) critical infrastructure protection (CIP) initiative in 2006. Its credibility on plausibility has been evidenced by attack events in the recent past. Although this is a "very high impact, rare probability" event, the establishment of quantitative measures would help asset owners in making a series of investment decisions. First, this dissertation tackles attackers' strategies based on the current communication architecture between remote IP-based (unmanned) power substations and energy control centers. Hypothetically, the identification of intrusion paths …


Optimization And Control Of An Array Of Wave Energy Converters, Jianyang Lyu Jan 2018

Optimization And Control Of An Array Of Wave Energy Converters, Jianyang Lyu

Dissertations, Master's Theses and Master's Reports

This study explored optimal configuration of both the array layout and the dimension of each WEC in the array. The array contains heaving buoys with full interaction and exact hydrodynamics. Optimization of dimension was done on each WEC in the array with a given optimal layout, and a higher q-factor was achieved. Both impedance matching optimal control and derivative control were employed, which provides both theoretical maximum energy and a more realistic case. Then the work was expanded to optimization of both the array layout and the dimension of each WEC in the array. An average of 39.21% higher q-factor …


Collaborative Fall Detection Using Smartphone And Kinect, Xue Li, Lanshun Nie, Hanchuan Xu, Xianzhi Wang Jan 2018

Collaborative Fall Detection Using Smartphone And Kinect, Xue Li, Lanshun Nie, Hanchuan Xu, Xianzhi Wang

Research Collection School Of Computing and Information Systems

Humanfall detection has attracted broad attentions as sensors and mobile devices are increasingly adopted in real-life scenarios such as smart homes. The complexity of activities in home environments pose severe challenges to the fall detection research with respect to the detection accuracy. We propose a collaborative detection platform that combines two subsystems: a threshold-based fall detection subsystem using mobile phones and a support vector machine (SVM)-based fall detection subsystem using Kinects. Both subsystems have their respective confidence models and the platform detects falls by fusing the data of both subsystems using two methods: the logical rules-based and D-S evidence fusion …


Real-Time Inbound Marketing: A Use Case For Digital Banking, Alan Megargel, Venky Shankararaman, Srinivas K. Reddy Jan 2018

Real-Time Inbound Marketing: A Use Case For Digital Banking, Alan Megargel, Venky Shankararaman, Srinivas K. Reddy

Research Collection School Of Computing and Information Systems

Over the years banks have been strategically using digital technologies to help transform various aspects of their business. In recent times, this strategy has evolved into one of digital augmentation of the bank’s processes, products and channels. This allows for reaching out to customers and partners through digital platforms, for example; the addition of mobile apps for customers to access and perform service transactions. Marketing continues to play a major role in supporting the expansion of business and increasing revenue for the bank. Marketing has evolved from mass direct targeting to more personalised, face-to-face and real-time targeting. In the digital …


Environmental Risk, Resource And Production, Nancye Gannaway Jan 2018

Environmental Risk, Resource And Production, Nancye Gannaway

Farm Systems and Economics published reports

Plan Prepare Prosper - workshop

Aims

  • To identify and plan for projected changes in weather patterns and in the physical resources that underpin the productivity of the farm enterprise.
  • To develop initiatives to manage observed and likely threats from the environment to farm enterprises.
  • To support the achievement of long-term economic viability of land under production

Today's content will help develop risk management strategies for agricultural production systems.


Cultivating The Capstone Ecosystem To Educate The Engineer Of 2020, Susannah Howe Jan 2018

Cultivating The Capstone Ecosystem To Educate The Engineer Of 2020, Susannah Howe

Engineering: Faculty Publications

Capstone design courses often provide authentic learning opportunities and real-world responsibility at the conclusion of students’ undergraduate engineering education, helping prepare them for their career and life trajectories after graduation. Cultivating the broader capstone design ecosystem can further enrich students’ learning, expand student connections, and facilitate acquisition of the Engineer of 2020 attributes. This paper presents a framework and associated strategies for a capstone design ecosystem that extends across the capstone design course, across the engineering department, across the institution, and across the alumni community. The paper discusses implementation of the proposed ecosystem approach as a case study supplemented by …


Preliminary Results From A Study Investigating The Transition From Capstone Design To Industry, Susannah Howe, Laura Mae Rosenbauer, Julie Dyke Ford, Nicholas Emory Alvarez, Marie C. Paretti, Chris Gewirtz, Daria A. Kotys-Schwartz, Daniel Knight, Cristian Hernandez Jan 2018

Preliminary Results From A Study Investigating The Transition From Capstone Design To Industry, Susannah Howe, Laura Mae Rosenbauer, Julie Dyke Ford, Nicholas Emory Alvarez, Marie C. Paretti, Chris Gewirtz, Daria A. Kotys-Schwartz, Daniel Knight, Cristian Hernandez

Engineering: Faculty Publications

This study investigates engineering students’ transitions from academic to professional environments by examining the role capstone design courses play in preparing graduates for the workplace. To better understand how capstone design experiences contribute to graduates’ professional preparation, we are collecting data from participants from four different institutions with project-based capstone courses as they begin post-graduation positions in a variety of engineering workplaces. Through quantitative and qualitative methods, our study is designed to collect insights from participants in their first 12 months on the job. Currently we are collecting and analyzing data from the first of two planned cohorts of participants. …


Nanoparticle Orientation To Control Rna Loading And Ligand Display On Extracellular Vesicles For Cancer Regression, Fengmei Pi, Daniel W. Binzel, Tae Jin Lee, Zhefeng Li, Meiyan Sun, Piotr G. Rychahou, Hui Li, Farzin Haque, Shaoying Wang, Carlo M. Croce, Bin Guo, B. Mark Evers, Peixuan Guo Jan 2018

Nanoparticle Orientation To Control Rna Loading And Ligand Display On Extracellular Vesicles For Cancer Regression, Fengmei Pi, Daniel W. Binzel, Tae Jin Lee, Zhefeng Li, Meiyan Sun, Piotr G. Rychahou, Hui Li, Farzin Haque, Shaoying Wang, Carlo M. Croce, Bin Guo, B. Mark Evers, Peixuan Guo

Markey Cancer Center Faculty Publications

Nanotechnology offers many benefits, and here we report an advantage of applying RNA nanotechnology for directional control. The orientation of arrow-shaped RNA was altered to control ligand display on extracellular vesicle membranes for specific cell targeting, or to regulate intracellular trafficking of small interfering RNA (siRNA) or microRNA (miRNA). Placing membrane-anchoring cholesterol at the tail of the arrow results in display of RNA aptamer or folate on the outer surface of the extracellular vesicle. In contrast, placing the cholesterol at the arrowhead results in partial loading of RNA nanoparticles into the extracellular vesicles. Taking advantage of the RNA ligand for …


Real-Time Image Pattern Sensor For Weld Pool Penetration Through Reflection In Gtaw, Yu-Ting Chen Jan 2018

Real-Time Image Pattern Sensor For Weld Pool Penetration Through Reflection In Gtaw, Yu-Ting Chen

Theses and Dissertations--Electrical and Computer Engineering

In gas tungsten arc welding (GTAW), weld pool surface contains crucial information for welding development. In this research, simulate skilled welders to control the welding process and determine the penetration stages based on the weld pool reaction.

This study focuses on solving the uncertainty of the liquid weld pool in joint bases. The weld pool penetration process is highly depending on how the weld pool surface shape. To observe the weld pool, reflect the weld pool surface by the laser and image on the shield glass. The experiments show that the penetration can’t be determine by the reflecting grayness due …


Design Of A Machine Vision Camera For Spatial Augmented Reality, Matt Phillip Ruffner Jan 2018

Design Of A Machine Vision Camera For Spatial Augmented Reality, Matt Phillip Ruffner

Theses and Dissertations--Electrical and Computer Engineering

Structured Light Imaging (SLI) is a means of digital reconstruction, or Three-Dimensional (3D) scanning, and has uses that span many disciplines. A projector, camera and Personal Computer (PC) are required to perform such 3D scans. Slight variances in synchronization between these three devices can cause malfunctions in the process due to the limitations of PC graphics processors as real-time systems. Previous work used a Field Programmable Gate Array (FPGA) to both drive the projector and trigger the camera, eliminating these timing issues, but still needing an external camera. This thesis proposes the incorporation of the camera with the FPGA SLI …


Economic Operation Of Typical Microgrids, Yuanzhen Guo Jan 2018

Economic Operation Of Typical Microgrids, Yuanzhen Guo

Theses and Dissertations--Electrical and Computer Engineering

A microgrid is a subnetwork of power system that consists of a group of distributed energy sources and loads. It is designed to integrate distributed generation, loads, energy storage devices, converters, and monitoring and protection devices. Generally, a successful microgrid could run both in island mode (off-grid) and in grid-connected mode (on-grid), being able to convert between two modes at any time. With continuous development of the power system, distributed renewable generation unit accounts for an increasing proportion, since microgrid could effectively connect these generation units to the main grid, thereby improving the energy efficiency and the energy structure. Microgrid …