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Location Context Awareness System for Specific Positioning Based on Received Signal Strength for Android Platform System
(2023-01-01)
Nonalinsavath, Khamla
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Khieovongphachanh, Vimontha
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Southisombath, Phouthong
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Chaisang, Aditep
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Phomkeona, Sanouphab
In the current era of seamless integration across various contexts, the ability to track mobility both indoors and outdoors has become crucial for many individuals. Tracking the path of mobility from the initial point to the final destination is essential in numerous aspects of human life. This study presents a location-Aware computing application that facilitates the smooth integration of indoor and outdoor environments by combining both requirements within a smart device-based system, without any barriers. The proposed work utilizes the Global Positioning System (GPS) and the Global System for Mobile Communications (GSM) to measure external conditions, while Wi-Fi Fingerprinting (Wi-Fi) is employed to accurately determine the user's indoor locations using received signal strength indicator. The integration of indoor and outdoor technologies ensures seamless user mobility. As users transition between different conditions, the system effectively addresses the complexities that arise between indoor and outdoor locations. The transition time between indoor and outdoor is less than 5 seconds, with seamless switching occurring in the overlapped areas. In our experiments conducted within a campus building, the system achieved a remarkable accuracy of 98.4% for outdoor-To-indoor movement and 97.7% for the reverse movement. Furthermore, the seamless location system offers significant benefits to users, including the discovery of new system features, access to directional maps, and guidance along pathways from their current locations.
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Characterization of Electromagnetic Wave in Transformer for Partial Discharge Detection
(2023-01-01)
Suwan, Supakorn
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Tiengthong, Thanadol
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Southisombath, Phouthong
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Promwong, Sathaporn
The increasing demand for electricity and the potential risks associated with partial discharge highlights the critical importance of robust transformer condition monitoring. Electromagnetic methods offer a promising approach to monitoring transformer health, benefiting from their ability to minimize external interference and their broad operating bandwidth covering HF, VHF, and UHF frequencies. The IEC 62478 standard provides multiple methodologies to leverage electromagnetic techniques in transformer health assessment, encompassing the analysis of electromagnetic waves through directivity, sensitivity, and transmission properties. In this study, we specifically investigate the transformer's UHF transmission characteristics. A vector network analyzer measures and records both transmitting and receiving elements of the UHF transmission channel and the UHF antenna. The measurements within the transformer tank simulate the realistic transformer environment. An optimum receiver is implemented at the receiver end to optimize the received signal quality. The results are comprehensively evaluated by analyzing the UHF transmission channel's path loss and transmission gain within the transformer. The primary objective of this research is to thoroughly examine the UHF transmission characteristics for efficient transformer condition monitoring, offering valuable insights for researchers and engineers involved in mitigating the risks associated with partial discharge in transformers.
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Experimental Evaluation of UWB Transmission Waveform with Body-Shadowing in an Indoor Environment
(2022-01-01)
Suwan, Supakorn
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Promwong, Sathaporn
Wireless radio transmission performance in a realistic environment is a significant issue for designing and evaluating in short-range transmission technologies. Human body-shadowing is a significant propagation effect in an indoor wireless communication network. This paper presents the measurement model of impulse radio transmission with human body-shadowing in an indoor environment with IEEE 802.15.4 multipath impulse parameters. The impulse radio transfer function measurement model for the human body impulse radio transfer function with frequency band cover from 3 GHz to 11 GHz. The optimum system evaluation of impulse radio transmission is due to the human body and antennas. The characteristics of impulse radio transmission loss are using decay factor, log-normal standard, clusters, and ray arrival rate. The contributions of this research can be evaluating the human body impulse radio transfer function. And the design of the wireless radio system with the body shadowing effects and ambient environments.
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A low power transmission model based UWB technology for BAN applications
(2020-07-01)
Suwan, Supakorn
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Southisombath, Khamphoui
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Promwong, Sathaporn
Low power transmission technology is ones of major concern in new wireless network (NWN) systems. The impulse radio is a potential technology to apply with body area network systems due to its transmit signal as impulse radio, which has low transmitted power. UWB gain high popular attention in short-range wireless communications development. Major kinds of application are able to used with UWB, e.g., wireless medical sensors networks, entertainment devices, and wireless localization. Information transmission in BAN systems is important for a reliable and accuracy in a actual used of medical sensors. In this research, the evaluation of UWB transmission model with human is introduce for analyze a distortion due to human body effect. The template waveform is proposed at the receiver side to achieve high level of SNR. The proposed model is very useful for the evaluation and design of wireless medical sensor networks including actual human body effect.
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Delay Time and Power Distribution of HB-UWB Transmission Based on Measurement Data
(2019-01-10)
Suwan, Supakorn
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Airphaiboon, Surapan
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Promwong, Sathaporn
Waveform distortion and delay time in human body-ultra wideband (HB-UWB) transmission waveform is very important parameters for in wireless impulse radio system. In this research, we investigated of human body effects and antennas in HB-UWB channel based on the based on measurement data work done in an indoor environment. The characteristics of the transceiver HB-UWB, which combine to form the signal and the effect signal receiver to get above the frequency band 3 GHz to 11 GHz important factors such as the distribution of power, distortion and delay spread. The RMS delay expand due to the human body shadowing and antennas are represent.
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Biometrics based on facial landmark with application in person identification
(2019-01-01)
Juhong, Aniwat
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Purahong, Boonchana
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Suwan, Supakorn
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Pitavirooj, Chuchart
This paper presents a novel technique for face recognition based on facial landmarks extracted automatically. Our landmarks are those associated with eyes mouth and nose. To extract facial landmarks, we first use Haar cascade algorithm to detect the face ROI following by Haar cascade algorithm for the eye, mouth and nose ROI determination. To find landmark associated with the eye, we convert eye ROI image to binary image using thresholding algorithm. To exclude the eyebrow region, we apply horizontal radon transform. The project data will then be used to separate the eyebrow region from the eye region. To detect eye-related landmark, vertical radon transform is applied. With the vertical projection data, the outermost pixel can be identified and the associated eye landmark can be determined. The similar technique can then be used to identify landmarks associated with the nose and mouth area. Given the correspond landmarks on the reference face and the query face, geometric transformation can be determined using normal equation bases on minimized mean squared error. The two faces are then aligned. To provide the quantitative measurement, the two aligned face are converted to edge image using canny edge algorithm. The distance map error between the two aligned edge facial images is then used to identify the query face. The purposed algorithm for person identification was tested on the face database resulting in a very high accuracy.
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Evaluation of WUWB Transmission with LOS and NLOS for Smart Home
(2018-07-02)
Chamchoy, Monchai
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Suwan, Supakorn
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Airphaiboon, Surapan
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Promwong, Sathaporn
Wireless ultra-wideband communications technology (WUWB) is a fast popular technology because many unique attractive features that promotes development about wireless communications, networking. WUWB has so high elevated and also allows the force spectral intensity to be so few, and the force limits on UWB are being severely limited by the regulatory bodies. Technology offers plenty advantages, particularly about terms of so high data transmission rates which are good above those probable with currently deployed technologies. The optimization of data transmission is to use multiantenna WUWB method. So, as an alternative, a multiantenna can be used to reduce the error rate as well as improve the quality and capability of wireless transmission by directing, with an aim to adventure the spatial diversity in the channel. The benefits of such a system can be found in independent relationships. This paper presents the spatial effects about transmitter/receiver relations for multiantenna UWB systems under line-of-sight (LOS) and non-line-of-sight (NLOS) situation. A comparison results exhibit that the relations reduce as the antenna length expand for the scenario. In the example of a NLOS situation, the relations does not rely on the spacing.
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Rapid E. coli detection based on fluorescence technique
(2017-12-19)
Suwan, Supakorn
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Phasuk, Kanchana
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Chitsakul, Kitiphol
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Piyawattanametha, Wibool
This research focuses on developing a prototype tool that is portable and develop method to detect Escherichia coli (E. coli) in water by measuring the light of fluorescence from an enzymatic reaction. The procedure can be done easily without need for laboratory professionals within 2 hours. Total coliforms can measure a minimum of at least 10 MPN/mL. This method is an alternative method to determine water quality. It can reduce the shipping water samples step to laboratories, reducing the time to wait for results. And reduces the cost of detecting E. coli, while the efficiency of this method is no different with the Most Probable Number method.
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Evaluation of rapid detection system for Escherichia coli in water samples
(2017-02-21)
Pipitsombat, Chanikarn
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Phasuk, Kanchana
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Suwan, Supakorn
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Piyawattanametha, Wibool
We demonstrated a fast detection platform for Escherichia coli (E. coli) in water. The system is based on a fluorescence detection technique by determining enzyme β-D-glucuronidase (GUD) activity and relating that activity to E. coli concentration. We found the portable E. coli detection platform is able to detect both the fluorescence 4-MU signal from the reaction of GUD assay from 0.01-1 μg/ml and to enumerate the number of E. coli in the range of 10<sup>5</sup>-10<sup>7</sup> CFU/ml. The required incubation time is in between 20-240 min. In addition, we can estimate the maximum of incubation time for detecting minimum of E. coli 1 CFU/ml from the equation to be 576 mins. Our preliminary study demonstrates that the system can be used to enumerate the number of E. coli in water on-site and requires less detection time than traditional E. coli methods.
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Hand shape identification using palmprint alignment based on intrinsic local affine-invariant fiducial points
(2014-01-20)
Phromsuthirak, Choopol
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Suwan, Supakorn
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Sanpanich, Arthorn
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Pintavirooj, Chuchart
Palmprint is the mostly popular biometrics used in security system. However, it is difficult to acquire the palmprint features with the common problems of pose, lighting, orientation, gesture etc. of palmprint image. So, these problems have the effect to reduce the level of confidence in personal authentication. In this paper, we proposed a new hand shape identification using palmprint alignment without guidance pegs algorithm for improving the level of confidence in palmprint identification system. The palmprint alignment based on a set of fiducial points which are intrinsic, local and preserved under affine transformation. The fiducial points are relative affine invariant to affine transformations, they allow for alignment where position of the palm relative to camera orientation can be arbitrary set. Moreover, before palmprint alignment process, the web camera which was used to capture the palmprint image was calibrated by Camera Calibration Toolbox developed by Jean-Yves Bouguet. The performance of the identification algorithm was tested in 2 types: intra-class identification and inter-class identification. The intra-class identification has the most of distance map error was started from 1.4 pixels to 4.5 pixels and the inter-class identification has 18 percent equal error rate.

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