The signal-to-noise ratio (SNR) - governed by the sensitivity and noise - determines the usefulness of a MEMS acoustic sensor. Low-SNR poses functional inability in a noisy environment and difficulty in signal process...
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The signal-to-noise ratio (SNR) - governed by the sensitivity and noise - determines the usefulness of a MEMS acoustic sensor. Low-SNR poses functional inability in a noisy environment and difficulty in signalprocessing. The literature is abundant with various approaches to mitigate low-SNR, however, it shows a lack of simultaneous improvement of sensitivity and noise. This paper reports on a MEMS piezoelectric acoustic sensor (PAS) with 7-30 dB higher SNR as compared to the state-of-the-art of PAS. The developed PAS uses analytically modeled aluminum nitride (AlN), and D33 transducer mode with a nominal electrode spacing, i.e., 20 mu m. At 1 kHz frequency, the measured SNR is found to be 67.03 dB which varies from 70 dB to 85 dB in the bandwidth. In addition to the substantial improvement of the SNR, the equivalent input-referred noise (EIN) is found to be 26.97 dB SPL;whereas, the A-weighted noise is 27.23 dBA which is the lowest noise ever analytically and experimentally reported in the state-of-the-art of PAS. Notably, all the measured results are found in full compliance with the analytical predictions. With the analytical and experimental results - in addition to its millimeter size - the developed PAS can be implemented in some cutting edge applications where an acoustic sensor with very high SNR is required like a mobile robot, noise monitoring, position tracking of the incoming sound, and voice-activated human-computer interaction. (C) 2020 Elsevier B.V. All rights reserved.
The extensive effort in manual labour for mould manufacturing is the main reason for outsourcing manufacturing resources to low-wage countries. Furthermore, the international mould and die sector faces a lack of skill...
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In this article, we discuss the detection of damage to the cutting tool used in robotised light mechanical processing. Continuous monitoring of the state of the tool mounted in the tool holder of the robot is required...
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In this article, we discuss the detection of damage to the cutting tool used in robotised light mechanical processing. Continuous monitoring of the state of the tool mounted in the tool holder of the robot is required due to the necessity to save time. The tool is a brush with ceramic fibres used for surface grinding. A typical example of damage to the brush is the breaking of fibres, resulting in a tool imbalance and vibrations at a high rotational speed, e.g. during grinding. This also results in a limited operating surface of the tool and a decrease in the efficiency of processing. While an imbalanced tool is spinning, fictitious forces occur that carry the information regarding the balance of the tool. The forces can be measured using a force sensor located in the end-effector of the robot allowing the assessment of the damage to the brush in an automatized way, devoid of any operator. (C) 2018 Elsevier Ltd. All rights reserved.
The viscosity of biofluids such as blood and saliva can reflect an individual's health conditions, and viscosity measurements are therefore considered in health monitoring and disease diagnosis. However, conventio...
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The viscosity of biofluids such as blood and saliva can reflect an individual's health conditions, and viscosity measurements are therefore considered in health monitoring and disease diagnosis. However, conventional viscometers can only handle a larger liquid volume beyond the quantity that can be extracted from a person. Though very effective, micro-sensors based on electrokinetic, ultrasonic, or other principles often have strict requirements for the supporting equipment and complicated procedures and signalprocessing. Sample contamination is always an important issue. In this paper, we report a microfluidic viscometer requiring a small volume of biosamples (<50 mu L) and straightforward operation procedures. It is fabricated with low-cost and biocompatible polymeric materials as one-time-use devices, such that contamination is no longer the concern. It contains a suspending micromembrane located along a microchannel. Under a steady driving pressure, the membrane displacement is a function of viscosity of the liquid sample being tested. We derived a simple analytical relation and perform a simulation for converting the membrane displacement to the sample viscosity. We conducted experiments with liquids (water and mineral oil) with defined properties to verify such a relation. We further applied the micro-viscometer to measure bovine blood samples with different hematocrit levels. It can be concluded that the microfluidic viscometer has a high compatibility with a broad range of biomedical applications.
Malaysian highway is one of the main used for travelling between states. Some of the location had improper road that causes puddles during raining. These puddles become dangerous to the driver especially when raining....
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ISBN:
(纸本)9781538603895
Malaysian highway is one of the main used for travelling between states. Some of the location had improper road that causes puddles during raining. These puddles become dangerous to the driver especially when raining. These will be affecting the efficiency of the vehicle tyre friction towards the road. From the loss of efficiency, the probability of vehicle to losing control is high and will compromising the driver and passenger safety. This project focused on the design, analyse and fabricate an autonomous robot that can detect the flatness of the surface by moving autonomously on the surface. The project system will be using Arduino as the microcontroller to interface with other sensors. The system will equip with Inertial Measurement Unit (IMU) sensor that will measure the orientation and heading of the robot. This system also will equip with rotary encoder that will measure the distance travel by the robot. For an autonomous navigation system, Proportional Derivative (PD) controller have been applied. Feedback signal from the IMU sensor represent orientation of the robot and accumulate with travel distance measured from rotary encoder. Manipulated data will be transmitting through serial communication via Bluetooth. Graphical User Interface (GUI) will be develop to visualize the gradient and travelling distance of the robot in order to interface for flatness inspection and navigation system.
Radar-based road user detection is an important topic in the context of autonomous driving applications. The resolution of conventional automotive radar sensors results in a sparse data representation which is tough t...
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ISBN:
(数字)9780578647098
ISBN:
(纸本)9781728168302
Radar-based road user detection is an important topic in the context of autonomous driving applications. The resolution of conventional automotive radar sensors results in a sparse data representation which is tough to refine during subsequent signalprocessing. On the other hand, a new sensor generation is waiting in the wings for its application in this challenging field. In this article, two sensors of different radar generations are evaluated against each other. The evaluation criterion is the performance on moving road user object detection and classification tasks. To this end, two data sets originating from an off-the-shelf radar and a high resolution next generation radar are compared. Special attention is given on how the two data sets are assembled in order to make them comparable. The utilized object detector consists of a clustering algorithm, a feature extraction module, and a recurrent neural network ensemble for classification. For the assessment, all components are evaluated both individually and, for the first time, as a whole. This allows for indicating where overall performance improvements have their origin in the pipeline. Furthermore, the generalization capabilities of both data sets are evaluated and important comparison metrics for automotive radar object detection are discussed. Results show clear benefits of the next generation radar. Interestingly, those benefits do not actually occur due to better performance at the classification stage, but rather because of the vast improvements at the clustering stage.
High-yielding cow rations under intensive production conditions contribute to the development of subacute rumen acidosis (SARA), leading to pathologies such as rumenitis, laminitis, reproductive disorders, loss of pro...
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ISBN:
(纸本)9781728167305
High-yielding cow rations under intensive production conditions contribute to the development of subacute rumen acidosis (SARA), leading to pathologies such as rumenitis, laminitis, reproductive disorders, loss of productivity and reduced longevity. The aim of this work is to develop a reticulo-ruminal long-acting cyber-physical system for monitoring rumen parameters. Three scientific institutions in cooperation with two farmers conduct the research in order to create a prototype of a low-power wireless sensor network system for early diagnostic of subacute rumen acidosis of dairy cows. The new system architecture includes, reticulo-ruminal bolus with pH and temperature sensors, a microcontroller, a radio transmitter and a power supply module. The system includes a base station for data collection from boluses, an MQTT broker, a web server and a database. Data communication solution has been developed and tested in the laboratory, and micro-controllers have been selected and adapted for data processing. In addition, research is under way to create an autonomous long-term power supply system. Work shall be conducted in two directions: (a) stand-alone battery-powered electricity supply system;(b) an autonomous power supply system based on the generation of an electrostatic generator. The results of the initial stage of the research are discussed in this paper.
In-1 order to minimize signal crosstalk, system noise and random noise interference and pseudo signals in the tactile sensing array to obtain high precision surface profile estimation, this paper explored the data pro...
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ISBN:
(纸本)9781450365123
In-1 order to minimize signal crosstalk, system noise and random noise interference and pseudo signals in the tactile sensing array to obtain high precision surface profile estimation, this paper explored the data processing.technology of robot tactile sensing suit based on fuzzy cognition map. In the paper, it discussed the structure, the modeling process and steps of fuzzy cognition map, made the anatomy of the shape of an object's surface contour recognition, and researched on the algorithm description of cognition map of robot tactile suit and the implementation of tactile sensing data processing. The simulation experiment would be simple and clear to verify the force condition of each sensing point and the distribution profile of different pressure range and the distribution and size of pressure peak. The research results show that the proposed design solution is reasonable feasible for data processing.of robotsensor suit.
The proceedings contain 22 papers. The special focus in this conference is on Artificial Intelligence and Natural Language processing. The topics include: Isan Dhamma Characters Segmentation and reading in Thai;ontolo...
ISBN:
(纸本)9783319947020
The proceedings contain 22 papers. The special focus in this conference is on Artificial Intelligence and Natural Language processing. The topics include: Isan Dhamma Characters Segmentation and reading in Thai;ontology-assisted structural design flaw detection of object-oriented software;virtual reality application for animal cruelty education;anti-theft motorcycle system using face recognition by deep learning under concept on Internet of Things;balanced scorecard quality information dashboards model for competitive business advantage;criminal background check program with fingerprint;Jobs analysis for business intelligence skills requirements in the ASEAN region: A text mining study;the model of teenager’s internet usage behavior analysis using data mining;privacy-preserving reputation management in fully decentralized systems: Challenges and opportunities;cloud-based services for cooperative robot learning of 3D object detection and recognition;empirical testing of a technique for assessing prior knowledge in the field of research training;problem content table construction based on extracting Sym-Multi-Word-Co from texts;Unpredictable disaster evacuation guide for weak people by real-time sensor network, SNS and maps;Detection of normal and abnormal ECG signal using ANN;dynamic relation-based analysis of objective interestingness measures in association rules mining;image encryption using cellular neural network and matrix transformation;improved term weighting factors for keyword extraction in hierarchical category structure and Thai text classification;ontology-based classifiers for wikipedia article quality classification;thai Named-Entity Recognition using variational long short-term memory with conditional random field;cardiac arrhythmia classification using Hjorth Descriptors.
The extensive effort in manual labour for mould manufacturing is the main reason for outsourcing manufacturing resources to low-wage countries. Furthermore, the international mould and die sector faces a lack of skill...
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The extensive effort in manual labour for mould manufacturing is the main reason for outsourcing manufacturing resources to low-wage countries. Furthermore, the international mould and die sector faces a lack of skilled workers due to the unattractive working conditions, for example the stressing, monotonous work and a partly hazardous working atmosphere (e.g. nickel dust). Especially, the finishing process (e.g. grinding, lapping, polishing) of freeform surfaces is still less automated in metal processing. Therefore, many efforts are initiated in order to fully automate the finishing process, but the today's approaches are usually limited on prototypal implemented and cost-intensive machine solutions. This work introduces a finishing control approach for freeform surfaces using a lightweight robot. The robot is used as an actuator as well as a sensor for closed-loop force control. The optimal force trajectory is determined by a CAD-model which describes the geometry of the workpiece. The noisy measured force signal is filtered by a Kalman filter which also estimates the system state for the model predictive controller (MPC). Finally, a simple position controller controls the position of the tool center point (TCP) and the MPC controls the force which occur on the tool. The results show that the force can be controlled with a higher accuracy than with a conventional impedance control, which is commercially provided. (C) 2019, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.
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