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... 38 (2003) 1389-1399. [3] Wan-Young Chung and Jun-Woo Lim, Patterning of Thin Tin Oxide Films with Nano-Size Particle for 2-Dimensional Micro Gas Sensor Airay, Current Applied Physics 3(2003)413-416. [4] Wan-Young ...
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In stereoscopic imaging technology, edge detection plays a significant role for obtaining depth and disparity information between two stereo image pairs. Till now, several researches are performed to analyze color image as well as black... more
In stereoscopic imaging technology, edge detection plays a significant role for obtaining depth and disparity information between two stereo image pairs. Till now, several researches are performed to analyze color image as well as black and white image for applying edge detection methods. In stereo vision, one of the popular approaches for disparity visualization is ‘Image Fusion’ method. This process is helpful for those stereo image pairs which has relatively larger disparity between them. But if some color stereo image pairs are considered which has lesser disparity then it becomes a quite difficult job to visualize the disparity by image fusion method. In this paper, a new approach to visualize the lesser horizontal disparity images is performed on single fused image which is based on ‘Image Binarization" method.
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Page 1. SM-GUI: A Grid-based XML Schema Management GUI Milan Kang1, Karpjoo Jeong1*, Sang Boem Lim1, Dongkwang Kim1, Ok-Hwan Byeon2 ... 7. Reference [1] Tim Bray and CM Sperberg-McQueen, "Extensible Markup Language (XML): Part I.... more
Page 1. SM-GUI: A Grid-based XML Schema Management GUI Milan Kang1, Karpjoo Jeong1*, Sang Boem Lim1, Dongkwang Kim1, Ok-Hwan Byeon2 ... 7. Reference [1] Tim Bray and CM Sperberg-McQueen, "Extensible Markup Language (XML): Part I. Syntax", World Wide Web ...
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Sun tanning is a process in which color of the skin changes, while staying in the sun for a prolong time, caused by the ultraviolet (UV) radiations. In this study, we developed a novel, smart, skincare RGB color device that can detect the... more
Sun tanning is a process in which color of the skin changes, while staying in the sun for a prolong time, caused by the ultraviolet (UV) radiations. In this study, we developed a novel, smart, skincare RGB color device that can detect the change in RGB color of the skin. The device could also harvest its energy from the near field communication (NFC) enabled smartphone, thus providing battery-less approach for the skincare support. Our smart skincare RGB device is integrated with two sensors: One for the detection of skin RGB color, and another for the detection of UV radiations from the sun. Based on the in vivo experimental results on different subjects, it was noted that different subjects were having different skin color types, therefore; change in RGB was different for each subject. Android application interface has also been provided in order to make the usage of this skincare device at ease. Finally, our smart skincare device is enclosed in a flexible 3D object that provides a very easy and convenient way to use, while taking it in the outside environment.
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This paper presents the results of study and analysis on the effects and influences caused by inaccurately measured environmental variables for ranging and localization purposes. These variables include path loss exponent, lognormal... more
This paper presents the results of study and analysis on the effects and influences caused by inaccurately measured environmental variables for ranging and localization purposes. These variables include path loss exponent, lognormal noise, and received signal strength measured at reference distance. Three cases of variable settings are included in the analysis for comparison: the actual, underestimated, and over-estimated values. The analysis involves two radio wave propagation models: the basic log-distance path loss model, and its extension log-normal path loss model. Log-distance path loss model is used in simulation, and log-normal path loss model is used in real-case experiment. Excluding the influence of log-normal shadowing and various fading effects, simulation reveals the enlargement and decrement of estimated length / space scale. Real-case experiment reveals the strengthening and weakening effects of log-normal variation due to under-estimated and overestimated path loss exponent. Concluding simulation and real-case experiment, it shows that over-estimated path loss exponent reduces the effects of log-normal noise but it also reduces the maximum reachable range in estimation. If choices are allowed between over-estimated and underestimated path loss exponent, the first choice is preferred.
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Falling is one of the most serious medical and social problems in aging population. Therefore taking care of the elderly by detecting activity and falling for preventing and mitigating the injuries caused by falls needs to be concerned.... more
Falling is one of the most serious medical and social problems in aging population. Therefore taking care of the elderly by detecting activity and falling for preventing and mitigating the injuries caused by falls needs to be concerned. This study proposes a wearable, wireless, battery free ultra-high frequency (UHF) smart sensor tag module for falling and activity detection. The proposed tag is powered by UHF RF wave from reader and read by a standard UHF Electronic Product Code (EPC) Class-1 Generation-2 reader. The battery free sensor module could improve the wearability of the wireless device. The combination of accelerometer signal and received signal strength indication (RSSI) from a reader in the passive smart sensor tag detect the activity and falling of the elderly very successfully. The fabricated smart sensor tag module has an operating range of up to 2.5m and conducting in real-time activity and falling detection.
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Particulate matter (PM) has a diameter of few micrometers, which causes different illnesses. We used visible light communication (VLC) to transfer PM data to a user monitoring terminal in real-time. To reduce the time and power required... more
Particulate matter (PM) has a diameter of few micrometers, which causes different illnesses. We used visible light communication (VLC) to transfer PM data to a user monitoring terminal in real-time. To reduce the time and power required for communication, we compressed the PM data. Subsequently, these compressed data were transmitted using a modulation technique called data-dependent multiple pulse position modulation (DDMPPM). We evaluate the performance of DDMPPM for multi-hop communication in VLC through practical experiments. For the same data set, DDMPPM utilizes a lesser frame to transfer PM data. Using DDMPPM, we achieved a total communication distance of 48 m.
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These particulate matter (PM) causes lethal diseases to humans, and both short term and long term exposure are known to have hazardous effects. PM10 and PM2.5 have diameters less 10 and $2.5~\mu \text{m}$ , respectively, which makes them... more
These particulate matter (PM) causes lethal diseases to humans, and both short term and long term exposure are known to have hazardous effects. PM10 and PM2.5 have diameters less 10 and $2.5~\mu \text{m}$ , respectively, which makes them more dangerous to the human body. Thus, information regarding PM concentrations in indoor environments of dust-sensitive places is essential for proper precaution. In this study, we measured PM values in a large area and transferred this information using visible light communication (VLC) to the monitoring node. VLC is considered as an efficient technique due to its unique advantages and is currently unregulated. We applied bidirectional VLC to transfer information to ensure two-way communication. We also applied a multihop strategy to make the system function as a query answering system at extended distances. At one end, we generated a request to relay the request to the proper node and received the response in the form of PM data. In our experiment, we implemented four nodes and conducted multihop communication utilizing only a VLC link. We achieved a distance of 13.5 m with a zero-error rate between the two nodes using nonreturn to zero on-off keying (NRZ-OOK) modulation. In case of multihop, we achieved a distance greater than 40 m using four nodes to send dust information with a minimal error rate. This can be applied to large indoor areas where radio frequency is restricted.
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For the past decade, it is well defined in the literature that fatigue is one of the most prospective factor in affecting the driver behavior. This paper presents a novel evaluation of driver fatigue condition based on multi-classifier... more
For the past decade, it is well defined in the literature that fatigue is one of the most prospective factor in affecting the driver behavior. This paper presents a novel evaluation of driver fatigue condition based on multi-classifier technique and fusion of attributes approach. The process involved fusion of attributes including image of eye movement and photoplethysmography (PPG) signals that are given as inputs to multi-classifier. In order to develop the best inference classifiers, artificial neural network (ANN), dynamic bayesian network (DBN), support vector machine (SVM), independent component analysis (ICA) and genetic algorithm (GA) were tested in our study. The output from each inference classifier are scaled and product in an intervention module to indicate driver aptitude in real-time. Implementation of monitoring system is practically designed in Android-based smartphone device where it can received all the sensory information from the dedicated sensors installed at the steering wheel via a small scale wireless sensor network. Device built-in front camera was utilized to capture driver facial image. No supplementary monitor is required to be installed in the vehicle as the all the information is to be displayed on the smartphone device itself. Warning system is triggered to warn driver once fatigue is suspected. System testing statistical results revealed that the manifold used of the proposed system demonstrates the advantages of performing information fusion, particularly with discrete methods, and the multi-classifier enabled a more authentic and ample driver fatigue evaluation.
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ABSTRACT
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Abstract A compact and long measurement range batteryless radio frequency sensor tag is designed and implemented for monitoring the freshness of packaged vegetables based on measured temperature and humidity values. The proposed system... more
Abstract A compact and long measurement range batteryless radio frequency sensor tag is designed and implemented for monitoring the freshness of packaged vegetables based on measured temperature and humidity values. The proposed system consists of a server personal computer, an RFID reader operating at a frequency of 13.56 MHz, and a temperature- and humidity-sensor tag. The proposed reader is equipped with a boost circuit to boost the circuit power up to 1 W and a 17 cm × 22 cm loop antenna to enhance the amplitude of the transceiver signal. Therefore, the proposed reader can read RF sensor tags at a distance of up to 30 cm, that is, relatively very long-range in 13.56 MHz. The proposed batteryless passive sensor tag can simultaneously measure temperature and humidity inside packaged vegetables, with accuracies of 97.8% and 98.5%, respectively. By measuring the temperature and humidity of the vegetables storage environment, we can predict the freshness of vegetables. This system implemented by using batteryless RF sensor that is expected to be a promising tool to help customers choose fresh vegetables.
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Increased driver stress is generally recognized as one of the major factors leading to road accidents and loss of life. Even though physiological signals are reported as the most reliable means to measure driver stresses, they often... more
Increased driver stress is generally recognized as one of the major factors leading to road accidents and loss of life. Even though physiological signals are reported as the most reliable means to measure driver stresses, they often require the use of unique and expensive sensors, which produce dynamic and varying readings within individuals. This paper presents a novel means to predict a driver’s stress level by evaluating the movement pattern of the steering wheel. This is accomplished by using an inertial motion unit sensor, which is placed on a glove worn by the driver. The motion sensor selected for this paper was chosen because for its low cost and the fact that it is least affected by environmental factors as compared with a physiological signal. Experiments were conducted in three different environmental scenarios. The scenarios were classified as “urban,” “highway,” and “rural,” and they were chosen to simulate contrasting stress conditions experienced by the driver. In this paper, skin conductance and driver self-reports served as a reference stress to predict the driver’s stress level. Galvanic skin response, a well-known stress indicator, was captured along the driver’s palm and the readings were transmitted to a mobile device via low energy Bluetooth for further processing. The results revealed that indirect measurement of steering wheel movement with an inertial motion sensor could obtain accuracies up to an average rate of 94.78%. This demonstrates the opportunity for inclusion of motion sensors in wireless driver assistance systems for ambulatory monitoring of stress levels.
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This paper represents the experimental implementation of an encryption-based visible light communication system for indoor communication over 14m, two single LED transmitters as the data source, and four receivers considered as data... more
This paper represents the experimental implementation of an encryption-based visible light communication system for indoor communication over 14m, two single LED transmitters as the data source, and four receivers considered as data receivers for performance evaluation.
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Scalable production of LPSCl-based sulfide solid-electrolytes with high ionic conductivities using various green and sustainable solvents for commercializing all-solid-state batteries.
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Abstract The proposed electrocardiogram (ECG) measurement system uses a nonintrusive ECG sensor with electrically active electrodes to measure an ECG signal without any noise effects. In this manner, the optimal position and size of the... more
Abstract The proposed electrocardiogram (ECG) measurement system uses a nonintrusive ECG sensor with electrically active electrodes to measure an ECG signal without any noise effects. In this manner, the optimal position and size of the active electrodes attached to a car seat can be selected from several practical scenarios considering the physical position of the subject's heart to minimize the noise effects for the nonintrusive ECG measurement system in the car. The ECG signals from a clothed and seated occupant of the automobile are measured at a sampling rate of 100 Hz. A signal conditioning circuit was also designed to reduce the noise effects generated by the internal circuitry. The ECG signals are measured and transmitted wirelessly to a base station connected to a server PC in a personal area network for signal processing. The driver's condition is monitored wirelessly and analyzed by performing a heart rate variability analysis in the time and frequency domains.
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Nowadays, wireless communication technologies are employed in medical body area networks to enhance flexibility and convenience for caregivers and patients. However, there is always the risk of disturbance from electromagnetic waves... more
Nowadays, wireless communication technologies are employed in medical body area networks to enhance flexibility and convenience for caregivers and patients. However, there is always the risk of disturbance from electromagnetic waves toward precision medical equipment. This study demonstrates a novel design and implementation of a medical healthcare information system using the emerging wireless visible light communication (VLC) technology. VLC technology can be implemented using visible light emitting diodes (LED), which is expected to be the main lighting source in the near future due to its energy efficient characteristic compared to conventional incandescent and fluorescent lighting. By manipulating the fast switching characteristic of LEDs, these lighting devices can be used simultaneously for illumination and wireless data communication. The prototype design of the VLC-based medical healthcare system can be used to provide data service and monitoring in radio frequency restricted hospital areas. High brightness LED (HB-LED) is used in the transmitter module to transmit medical and healthcare information using optical modulation method. High speed photodetector is used to detect the optical signal, then the signal is demodulated and conditioned at the receiver module. Medical caregivers or patients can download the biomedical data and healthcare information using a portable device with attached optical sensor.
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For implementing the ubiquitous computing environments, the recent increasing attraction on communication systems has been driving the theory and technology of the related fields. Among these related problems, the minimum spanning tree... more
For implementing the ubiquitous computing environments, the recent increasing attraction on communication systems has been driving the theory and technology of the related fields. Among these related problems, the minimum spanning tree (MST) problems, which are one of the basic combinatorial optimization problems, have many applications in the communication systems. Especially, the optimal communication spanning tree (OCST) problem is the famous application of MST problem. The OCST problem is defined by finding a spanning tree that connects all nodes and satisfies their communication requirements for connecting all nodes. This OCST problem can be applied in the many network optimization problems, such as network topology design problems, multicast tree configuration problems, and ad-hoc network or ubiquitous sensor network routing problems, and so forth. This paper presents a genetic algorithm with a new encoding method, which is based on the Prufer number (PN) and a clustering string, for solving the OCST problems. Finally, we will see clearly that the efficiency and effectiveness of our proposed method, employed as the solution method of the OCST problems, can be shown by several experimental results.