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Performance Analysis of Implementation on IoT based Smart Wearable Mine Detection Device

  • Kim, Chi-Wook
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.12
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    • pp.51-57
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    • 2019
  • In this paper, we analyzed the performance of IoT based smart wearable mine detection device. There are various mine detection methods currently used by the military. Still, in the general field, mine detection is performed by visual detection, probe detection, detector detection, and other detection methods. The detection method by the detector is using a GPR sensor on the detector, which is possible to detect metals, but it is difficult to identify non-metals. It is hard to distinguish whether the area where the detection was performed or not. Also, there is a problem that a lot of human resources and time are wasted, and if the user does not move the sensor at a constant speed or moves too fast, it is difficult to detect landmines accurately. Therefore, we studied the smart wearable mine detection device composed of human body antenna, main microprocessor, smart glasses, body-mounted LCD monitor, wireless data transmission, belt type power supply, black box camera, which is to improve the problem of the error of mine detection using unidirectional ultrasonic sensing signal. Based on the results of this study, we will conduct an experiment to confirm the possibility of detecting underground mines based on the Internet of Things (IoT). This paper consists of an introduction, experimental environment composition, simulation analysis, and conclusion. Introduction introduces the research contents such as mines, mine detectors, and research progress. It consists of large anti-personnel mine, M16A1 fragmented anti-mine, M15 and M19 antitank mines, plastic bottles similar to mines and aluminum cans. Simulation analysis is conducted by using MATLAB to analyze the mine detection device implementation performance, generating and transmitting IoT signals, and analyzing each received signal to verify the detection performance of landmines. Then we will measure the performance through the simulation of IoT-based mine detection algorithm so that we will prove the possibility of IoT-based detection landmine.

Requirement Analysis of Satellite On-the-Move Transportable Terminal System (이동통신형 차량위성단말 시스템 요구사항 분석)

  • Oh, Il-Hyuk;Song, Choong-Ho;Ko, Dong-Kuk
    • Journal of Satellite, Information and Communications
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    • v.3 no.1
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    • pp.41-47
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    • 2008
  • Line-of-sight communications cannot easily support korean armed forces because of mountainous terrain. ADD(Agency for Defense Development) introduced ANASIS(Army Navy Air-force Satellite Information System) to meet the Korean warfighter's operational needs. Currently, army's military satcom terminal is designed for either fixed site or on-the-pause operation. The US army is under development of multi-band integrated on-the-move satellite terminals to let the army's communication capability to keep pace with globally deployable Joint Task Force for network-centric application. In this paper we analyzed X-band and Ka-band link and subsystem requirement. Our focus here is to describe key technical issues. Especially, On the basis of 3dB beam width of 0.9m antenna, Tracking accuracy and disturbances compensation signal processing on-the-move of Antenna Tracking system is analyzed. Also, protocol is analyzed that minimize blockage on the move due to an obstacle. when the received signal blocked, it stop to transmit burst signal and retransmit when blockage removed through received synchronization signal monitoring. Analyzed specification will be used to make prototype terminal to analyze risk for mass production

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Development of MRI Simulator Early Diagnosis Program for Self Learning (자가 학습을 위한 MRI Simulator 초기 검사 프로그램 개발)

  • Jeong, Cheon-Soo;Kim, Chong-Yeal
    • The Journal of the Korea Contents Association
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    • v.15 no.9
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    • pp.403-410
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    • 2015
  • Since 1970, MRI has greatly been developing in terms of strength of magnetic field, the number of receipt channels, and short time of examination. With the development of digital systems and wireless network, hospitals have also acquired, saved, and managed digital images taken by various kinds of medical imaging equipment. However, domestic universities fail to provide practice training course independently thanks to expensive practice equipment and high maintenance cost, and rely on clinical training. Therefore, this study developed a MR patient diagnosis program based on Windows PC to help out students before their working in clinical filed. The designed Relational Database of MRI Simulator is made up of seven tables according to functions and data characteristics. Regarding the designed patient information, each stepwise function was classified by the patient registration method in clinical field. In addition, on the assumption of the basic information for diagnosis, each setting and content were classified. The menu by execution step was arrayed on the left side for easy view. For patient registration, a patient's name, gender, unique ID, birth date, weight, and other types of basic information were entered, and the patient's posture and diagnosis direction were set up. In addition, the body regions for diagnosis and Pulse Sequence were listed for selection. Also, Protocol name and other additional factors were allowed to be entered. The final window was designed to check diagnosis images, patient information, and diagnosis conditions. By learning how to enter patient information and change diagnosis conditions in this program, users will be able to understand more theories and terms learned in practice and thereby to shorten their learning time in actual clinical work.

New SNR Estimation Algorithm using Preamble and Performance Analysis (프리앰블을 이용한 새로운 SNR 추정 알고리즘 제안 및 성능 분석)

  • Seo, Chang-Woo;Yoon, Gil-Sang;Portugal, Sherlie;Hwang, In-Tae
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.48 no.3
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    • pp.6-12
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    • 2011
  • The fast growing of the number of users requires the development of reliable communication systems able to provide higher data rates. In order to meet those requirements, techniques such as Multiple Input Multiple Out (MIMO) and Orthogonal Frequency Division multiplexing (OFDM) have been developed in the recent years. In order to combine the benefits of both techniques, the research activity is currently focused on MIMO-OFDM systems. In addition, for a fast wireless channel environment, the data rate and reliability can be optimized by setting the modulation and coding adaptively according to the channel conditions; and using sub-carrier frequency, and power allocation techniques. Depending on how accurate the feedback-based system obtain the channel state information (CSI) and feed it back to the transmitter without delay, the overall system performance would be poor or optimal. In this paper, we propose a Signal to Noise Ratio (SNR) estimation algorithm where the preamble is known for both sides of the transciever. Through simulations made over several channel environments, we prove that our proposed SNR estimation algorithm is more accurate compared with the traditional SNR estimation.

Throughput Performance analysis of AMC based on New SNR Estimation Algorithm using Preamble (프리앰블을 이용한 새로운 SNR 추정 알고리즘 기반의 AMC 기법의 전송률 성능 분석)

  • Seo, Chang-Woo;Portugal, Sherlie;Hwang, In-Tae
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.48 no.4
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    • pp.6-14
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    • 2011
  • The fast growing of the number of users requires the development of reliable communication systems able to provide higher data rates. In order to meet those requirements, techniques such as Multiple Input Multiple Out (MIMO) and Orthogonal Frequency Division multiplexing (OFDM) have been developed in the recent years. In order to combine the benefits of both techniques, the research activity is currently focused on MIMO-OFDM systems. In addition, for a fast wireless channel environment, the data rate and reliability can be optimized by setting the modulation and coding adaptively according to the channel conditions; and using sub-carrier frequency, and power allocation techniques. Depending on how accurate the feedback-based system obtain the channel state information (CSI) and feed it back to the transmitter without delay, the overall system performance would be poor or optimal. In this paper, we propose a Signal to Noise Ratio (SNR) estimation algorithm where the preamble is known for both sides of the transciever. Through simulations made over several channel environments, we prove that our proposed SNR estimation algorithm is more accurate compared with the traditional SNR estimation. Also, We applied AMC on several channel environments using the parameters of IEEE 802.11n, and compared the Throughput performance when using each of the different SNR Estimation Algorithms. The results obtained in the simulation confirm that the proposed algorithm produces the highest Throughput performance.

Compact 0th Order Antenna for 2.4 GHz ISM Band (2.4 GHz ISM대역용 소형 0차 공진 안테나)

  • Do, Sang-In;Yoo, Jin-Ha;Lee, Young-Soon
    • Journal of Advanced Navigation Technology
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    • v.19 no.1
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    • pp.60-65
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    • 2015
  • In the present study, compact $0^{th}$ order resonant antenna for 2.4 GHz ISM frequency band is newly proposed. In case of wireless communication systems such as wi-fi, bluetooth and Zigbee, antennas with omni-directional radiation pattern are necessary because of the demands for uniformly received electric field strength without variation for direction. It is well-known that $0^{th}$ order resonant antennas are not only advantageous for miniaturization but also have advantage of maintaining omni-directional radiation pattern. The proposed antenna is composed of two-element array in which the size of unit element should be smaller than ${\lambda}/4$ correspondent to the resonant length of typical monopole antennas The proposed antenna which is placed at middle and upper side of PCB with $50{\times}50mm^2$ size is designed and fabricated within limited space of $8{\times}5mm^2$. The measured impedance bandwidth ($S_{11}{\leq}-10dB$) is about 100 MHz (2.4~2.5 GHz) which corresponds to quite wide bandwidth in comparison with the antenna size, and also the measured peak gain over the passband is more than 3 dBi which is thought to be slightly wider than the other $0^{th}$ order resonant antenna.

A Study on the Propagation Environment for VHF Maritime Digital Communications Operation in South Sea Area (남해안의 VHF 해상디지털통신 운용을 위한 전파환경 연구)

  • Ju, Yang-Ro;Kim, Kab-Ki;Choi, Jo-Cheon;Lee, Seong-Ro
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.6
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    • pp.1310-1316
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    • 2014
  • The IMO has recommended on VHF digital communications operation for sailing ships from 2017. And ships more than 5 tons is obliged to digital communications by fishing Vessels Act and Vessel Safety Act in domestic. The owner of all vessel is equipped to the automatic position reporting device in accordance with the Notice of the Ministry of Oceans and Fisheries to regulations, It shall be ensure to navigations safety and in order to respond quickly in the event of maritime accidents on all vessels. The info-communications station of fishery is operating the automatic position reporting system using the VHF DSC in east sea from 2012, Continuously, which is underway the install plan in south sea and yellow sea. But this plan is very difficult, because of propagation environment is poor on account of complicated coastline and many islands. This paper has analyzed the propagation coverage for position setting of coast station in south sea and the traffic zone set up by compare with RSSI and methode of navigation tracking by VMS.