Abstract: In this paper, we propose a new method to distinguish
between arousal and relaxation states by using multiple features
acquired from a photoplethysmogram (PPG) and support vector
machine (SVM). To induce arousal and relaxation states in subjects, 2
kinds of sound stimuli are used, and their corresponding biosignals are
obtained using the PPG sensor. Two features–pulse to pulse interval
(PPI) and pulse amplitude (PA)–are extracted from acquired PPG
data, and a nonlinear classification between arousal and relaxation is
performed using SVM.
This methodology has several advantages when compared with
previous similar studies. Firstly, we extracted 2 separate features from
PPG, i.e., PPI and PA. Secondly, in order to improve the classification
accuracy, SVM-based nonlinear classification was performed.
Thirdly, to solve classification problems caused by generalized
features of whole subjects, we defined each threshold according to
individual features.
Experimental results showed that the average classification
accuracy was 74.67%. Also, the proposed method showed the better
identification performance than the single feature based methods.
From this result, we confirmed that arousal and relaxation can be
classified using SVM and PPG features.
Abstract: Repeated observation of a given area over time yields
potential for many forms of change detection analysis. These
repeated observations are confounded in terms of radiometric
consistency due to changes in sensor calibration over time,
differences in illumination, observation angles and variation in
atmospheric effects.
This paper demonstrates applicability of an empirical relative
radiometric normalization method to a set of multitemporal cloudy
images acquired by Resourcesat1 LISS III sensor. Objective of this
study is to detect and remove cloud cover and normalize an image
radiometrically. Cloud detection is achieved by using Average
Brightness Threshold (ABT) algorithm. The detected cloud is
removed and replaced with data from another images of the same
area. After cloud removal, the proposed normalization method is
applied to reduce the radiometric influence caused by non surface
factors. This process identifies landscape elements whose reflectance
values are nearly constant over time, i.e. the subset of non-changing
pixels are identified using frequency based correlation technique. The
quality of radiometric normalization is statistically assessed by R2
value and mean square error (MSE) between each pair of analogous
band.
Abstract: This paper shows the potential system benefits of
simple tracking solar system using a stepper motor and light sensor.
This method is increasing power collection efficiency by developing
a device that tracks the sun to keep the panel at a right angle to its
rays. A solar tracking system is designed, implemented and
experimentally tested. The design details and the experimental results
are shown.
Abstract: A measurement system for pH array sensors is
introduced to increase accuracy, and decrease non-ideal effects
successfully. An array readout circuit reads eight potentiometric
signals at the same time, and obtains an average value. The deviation
value or the extreme value is counteracted and the output voltage is a
relatively stable value. The errors of measuring pH buffer solutions are
decreased obviously with this measurement system, and the non-ideal
effects, drift and hysteresis, are lowered to 1.638mV/hr and 1.118mV,
respectively. The efficiency and stability are better than single sensor.
The whole sensing characteristics are improved.
Abstract: We present an explicit expression to estimate driving voltage attenuation through RC networks representation of an ultrahigh- speed image sensor. Elmore delay metric for a fundamental RC chain is employed as the first-order approximation. By application of dimensional analysis to SPICE simulation data, we found a simple expression that significantly improves the accuracy of the approximation. Estimation error of the resultant expression for uniform RC networks is less than 2%. Similarly, another simple closed-form model to estimate 50 % delay through fundamental RC networks is also derived with sufficient accuracy. The framework of this analysis can be extended to address delay or attenuation issues of other VLSI structures.
Abstract: The aim of this study is to develop a cost-effective WBGT heat stress monitor which provides precise heat stress measurement. The proposed device employs SHT15 and DS18B20 as a temperature and humidity sensors, respectively, incorporating with ATmega328 microcontroller. The developed heat stress monitor was calibrated and adjusted to that of the standard temperature and humidity sensors in the laboratory. The results of this study illustrated that the mean percentage error and the standard deviation from the measurement of the globe temperature was 2.33 and 2.71 respectively, while 0.94 and 1.02 were those of the dry bulb temperature, 0.79 and 0.48 were of the wet bulb temperature, and 4.46 and 1.60 were of the relative humidity sensor. This device is relatively low-cost and the measurement error is acceptable.
Abstract: Nanocrystalline thin film of Na0.1V2O5.nH2O xerogel
obtained by sol gel synthesis was used as gas sensor. Gas sensing
properties of different gases such as hydrogen, petroleum and
humidity were investigated. Applying XRD and TEM the size of the
nanocrystals is found to be 7.5 nm. SEM shows a highly porous
structure with submicron meter-sized voids present throughout the
sample. FTIR measurement shows different chemical groups
identifying the obtained series of gels. The sample was n-type
semiconductor according to the thermoelectric power and electrical
conductivity. It can be seen that the sensor response curves from
130oC to 150oC show a rapid increase in sensitivity for all types of
gas injection, low response values for heating period and the rapid
high response values for cooling period. This result may suggest that
this material is able to act as gas sensor during the heating and
cooling process.
Abstract: In over deployed sensor networks, one approach
to Conserve energy is to keep only a small subset of sensors
active at Any instant. For the coverage problems, the monitoring
area in a set of points that require sensing, called demand points, and
consider that the node coverage area is a circle of range R, where R
is the sensing range, If the Distance between a demand point and
a sensor node is less than R, the node is able to cover this point. We
consider a wireless sensor network consisting of a set of sensors
deployed randomly. A point in the monitored area is covered if it is
within the sensing range of a sensor. In some applications, when the
network is sufficiently dense, area coverage can be approximated by
guaranteeing point coverage. In this case, all the points of wireless
devices could be used to represent the whole area, and the working
sensors are supposed to cover all the sensors. We also introduce
Hybrid Algorithm and challenges related to coverage in sensor
networks.
Abstract: Water leakage is a serious problem in the maintenance of a waterworks facility. Monitoring the water flow rate is one way to locate leakage. However, conventional flowmeters such as the wet-type flowmeter and the clamp-on type ultrasonic flowmeter require additional construction for their installation and are therefore quite expensive. This paper proposes a novel estimation system for the flow rate in a water pipeline, which employs a vibration sensor. This assembly can be attached to any water pipeline without the need for additional high-cost construction. The vibration sensor is designed based on a condenser microphone. This sensor detects vibration caused by water flowing through a pipeline. It is possible to estimate the water flow rate by measuring the amplitude of the output signal from the vibration sensor. We confirmed the validity of the proposed sensing system experimentally.
Abstract: In this paper, a fiber based Fabry-Perot interferometer
is proposed and demonstrated for a non-contact displacement
measurement. A piece of micro-prism which attached to the
mechanical vibrator is served as the target reflector. Interference
signal is generated from the superposition between the sensing beam
and the reference beam within the sensing arm of the fiber sensor.
This signal is then converted to the displacement value by using a
developed program written in visual Cµ programming with a
resolution of λ/8. A classical function generator is operated for
controlling the vibrator. By fixing an excitation frequency of 100 Hz
and varying the excitation amplitude range of 0.1 – 3 Volts, the
output displacements measured by the fiber sensor are obtained from
1.55 μm to 30.225 μm. A reference displacement sensor with a
sensitivity of ~0.4 μm is also employed for comparing the
displacement errors between both sensors. We found that over the
entire displacement range, a maximum and average measurement
error are obtained of 0.977% and 0.44% respectively.
Abstract: For most image fusion algorithms separate
relationship by pixels in the image and treat them more or less
independently. In addition, they have to be adjusted different
parameters in different time or weather. In this paper, we propose a
region–based image fusion which combines aspects of feature and
pixel-level fusion method to replace only by pixel. The basic idea is
to segment far infrared image only and to add information of each
region from segmented image to visual image respectively. Then we
determine different fused parameters according different region. At
last, we adopt artificial neural network to deal with the problems of
different time or weather, because the relationship between fused
parameters and image features are nonlinear. It render the fused
parameters can be produce automatically according different states.
The experimental results present the method we proposed indeed
have good adaptive capacity with automatic determined fused
parameters. And the architecture can be used for lots of applications.
Abstract: The amplitude response of infrared (IR) sensors
depends on the reflectance properties of the target. Therefore, in
order to use IR sensor for measuring distances accurately, prior
knowledge of the surface must be known. This paper describes the
Phong Illumination Model for determining the properties of a surface
and subsequently calculating the distance to the surface. The angular
position of the IR sensor is computed as normal to the surface for
simplifying the calculation. Ultrasonic (US) sensor can provide the
initial information on distance to obtain the parameters for this
method. In addition, the experimental results obtained by using
LabView are discussed. More care should be taken when placing the
objects from the sensors during acquiring data since the small change
in angle could show very different distance than the actual one.
Since stereo camera vision systems do not perform well under some
environmental conditions such as plain wall, glass surfaces, or poor
lighting conditions, the IR and US sensors can be used additionally to
improve the overall vision systems of mobile robots.
Abstract: There are several means to measure the oxidation of edible oils, such as the acid value, the peroxide value, and the anisidine value. However, these means require large quantities of reagents and are time-consuming tasks. Therefore, a more convenient and time-saving way to measure the oxidation of edible oils is required. In this report, an edible oil condition sensor was fabricated by using single-walled nanotubes (SWNT). In order to test the sensor, oxidized edible oils, each one at a different acid value, were prepared. The SWNT sensors were immersed into these oxidized oils and the resistance changes in the sensors were measured. It was found that the conductivity of the sensors decreased as the oxidation level of oil increased. This result suggests that a change of the oil components induced by the oxidation process in edible oils is related to the conductivity change in the SWNT sensor.
Abstract: The whole work is based on possibility to use Lego Mindstorms robotics systems to reduce costs. Lego Mindstorms consists of a wide variety of hardware components necessary to simulate, programme and test of robotics systems in practice. To programme algorithm, which simulates space using the ultrasonic sensor, was used development environment supplied with kit. Software Matlab was used to render values afterwards they were measured by ultrasonic sensor. The algorithm created for this paper uses theoretical knowledge from area of signal processing. Data being processed by algorithm are collected by ultrasonic sensor that scans 2D space in front of it. Ultrasonic sensor is placed on moving arm of robot which provides horizontal moving of sensor. Vertical movement of sensor is provided by wheel drive. The robot follows map in order to get correct positioning of measured data. Based on discovered facts it is possible to consider Lego Mindstorm for low-cost and capable kit for real-time modelling.
Abstract: Sensors have been used in various kinds of academic
fields and applications. In this article, we propose the idea of
modularized sensors that combine multiple sensor modules into a
unique sensor. We divide a sensor into several units according to
functionalities. Each unit has different sensor modules, which share
the same type of connectors and can be serially and arbitrarily
connected each other. A user can combine different sensor modules
into a sensor platform according to requirements. Compared with
current modularized sensors, the proposed sensor platform is highly
flexible and reusable. We have implemented the prototype of the
proposed sensor platform, and the experimental results show the
proposed platform can work correctly.
Abstract: The need for micromechanical inertial sensors is increasing
in future electronic stability control (ESC) and other positioning,
navigation and guidance systems. Due to the rising density of
sensors in automotive and consumer devices the goal is not only to get
high performance, robustness and smaller package sizes, but also to
optimize the energy management of the overall sensor system. This
paper presents an evaluation concept for a surface micromachined
yaw rate sensor. Within this evaluation concept an energy-efficient
operation of the drive mode of the yaw rate sensor is enabled. The
presented system concept can be realized within a power management
subsystem.
Abstract: An optical fiber Fabry-Perot interferometer (FFPI) is
proposed and demonstrated for dynamic measurements in a
mechanical vibrating target. A polishing metal with a low reflectance
value adhered to a mechanical vibrator was excited via a function
generator at various excitation frequencies. Output interference
fringes were generated by modulating the reference and sensing
signal at the output arm. A fringe-counting technique was used for
interpreting the displacement information on the dedicated computer.
The fiber interferometer has been found the capability of the
displacement measurements of 1.28 μm – 96.01 μm. A commercial
displacement sensor was employed as a reference sensor for
investigating the measurement errors from the fiber sensor. A
maximum percentage measurement error of approximately 1.59 %
was obtained.
Abstract: This paper describes the process used in the
automation of the Maritime UAV commands using the Kinect sensor.
The AR Drone is a Quadrocopter manufactured by Parrot [1] to be
controlled using the Apple operating systems such as iPhones and
Ipads. However, this project uses the Microsoft Kinect SDK and
Microsoft Visual Studio C# (C sharp) software, which are compatible
with Windows Operating System for the automation of the navigation
and control of the AR drone.
The navigation and control software for the Quadrocopter runs on
a windows 7 computer. The project is divided into two sections; the
Quadrocopter control system and the Kinect sensor control system.
The Kinect sensor is connected to the computer using a USB cable
from which commands can be sent to and from the Kinect sensors.
The AR drone has Wi-Fi capabilities from which it can be connected
to the computer to enable transfer of commands to and from the
Quadrocopter.
The project was implemented in C#, a programming language that
is commonly used in the automation systems. The language was
chosen because there are more libraries already established in C# for
both the AR drone and the Kinect sensor.
The study will contribute toward research in automation of
systems using the Quadrocopter and the Kinect sensor for navigation
involving a human operator in the loop. The prototype created has
numerous applications among which include the inspection of vessels
such as ship, airplanes and areas that are not accessible by human
operators.
Abstract: This paper aims at overviewing the topics of a research project (CARDIOSENSOR) on the field of health sciences (biomaterials and biomedical engineering). The project has focused on the development of a nanosensor for the assessment of the risk of cardiovascular diseases by the monitoring of C-reactive protein (CRP), which has been currently considered as the best validated inflammatory biomarker associated to cardiovascular diseases. The project involves tasks such as: 1) the development of sensor devices based on field effect transistors (FET): assembly, optimization and validation; 2) application of sensors to the detection of CRP in standard solutions and comparison with enzyme-linked immunosorbent assay (ELISA); and 3) application of sensors to real samples such as blood and saliva and evaluation of their ability to predict the risk of cardiovascular disease.
Abstract: A novel low-cost impedance control structure is
proposed for monitoring the contact force between end-effector and
environment without installing an expensive force/torque sensor.
Theoretically, the end-effector contact force can be estimated from the
superposition of each joint control torque. There have a nonlinear
matrix mapping function between each joint motor control input and
end-effector actuating force/torques vector. This new force control
structure can be implemented based on this estimated mapping matrix.
First, the robot end-effector is manipulated to specified positions, then
the force controller is actuated based on the hall sensor current
feedback of each joint motor. The model-free fuzzy sliding mode
control (FSMC) strategy is employed to design the position and force
controllers, respectively. All the hardware circuits and software
control programs are designed on an Altera Nios II embedded
development kit to constitute an embedded system structure for a
retrofitted Mitsubishi 5 DOF robot. Experimental results show that PI
and FSMC force control algorithms can achieve reasonable contact
force monitoring objective based on this hardware control structure.