Implementation of Two-way Data Link using the Thuraya Geostationary Orbit Satellite
장원창 Won-chang Jang , 이명의 Myung-eui Lee
23(5) 333-338, 2019
장원창 Won-chang Jang , 이명의 Myung-eui Lee
DOI: JANT Vol.23(No.5) 333-338, 2019
Satellite communication is not used by many people like mobile communication, but it is a necessary technology for public service and communication services, such as providing the Internet in military, disaster, remote education and medical services, island areas, and infrastructure vulnerable areas. However, most communication modems have problems with two-way communication with server as IP addresses are assigned to floating IP that change every time they communicate with the network. In this paper, we used the Raspberry Pi as the controller of the terminal device to communicate the network through the satellite modem and the PPP protocol, and to solve the problem of the modem with the floating IP, we used the text message function of the satellite modem. Through this process, two-way data links using the Thuraya geostationary orbit satellite were implemented.
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Guided Missile Assembly Test Set using Encryption AES Rijndael Algorithm
정의재 Eui-jae Jung , 고상훈 Sang-hoon Koh , 이유상 You-sang Lee , 김영성 Young-sung Kim
23(5) 339-344, 2019
정의재 Eui-jae Jung , 고상훈 Sang-hoon Koh , 이유상 You-sang Lee , 김영성 Young-sung Kim
DOI: JANT Vol.23(No.5) 339-344, 2019
In order to prepare for the rise of data security threats caused by the information and communication technology, technology that can guarantee the stability of the data stored in the missile test set is important. For this purpose, encryption should be performed when data is stored so that it cannot be restored even if data is leaked, and integrity should be ensured even after decrypting the data. In this paper, we apply AES algorithm, which is a symmetric key cryptography system, to the missile test set, and Encrypt and decrypt according to the amount of data for each bit of each AES algorithm. We implemented the AES Rijndael algorithm in the existing inspection system to analyze the effect of encryption and apply the proposed encryption algorithm to the existing system. confirmation of suitability. analysis of capacity and Algorithm bits it is confirmed that the proposed algorithm will not affect the system operation and the optimal algorithm is derived. compared with the initial data, we can confirm that the algorithm can guarantee data undulation.
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Development of Real Time Simulation Environment Based on DEVS Formalism Applicable to Avionics System Integration Laboratory
서민기 Min-gi Seo , 신주철 Ju-chul Shin , 백경훈 Gyong-hoon Baek , 김성우 Seong-woo Kim
23(5) 345-351, 2019
서민기 Min-gi Seo , 신주철 Ju-chul Shin , 백경훈 Gyong-hoon Baek , 김성우 Seong-woo Kim
DOI: JANT Vol.23(No.5) 345-351, 2019
Avionics System Integration Laboratory is an integrated test environment for the integration and the verification of avionics systems. Recently, in order to fully consider the requirements verification of avionics system from the aspect of the entire system integration, the participation in the development of the SIL field is advanced from the requirement analysis of the aircraft. Efforts are being made to minimize the cost and the period of development of a SIL so that it does not affect the overall schedule of the aircraft development. We propose the avionics simulation model framework (ASMF) based on the modeling formalism applicable to SIL in order to reduce development period/cost and increase maintenance by standardizing the modeling methods of SIL.
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Docking Assessment Algorithm for AUVs with Uncertainties
천승재 Seung-jae Chon , 서주노 Joo-no Sur , 정성훈 Seong-hoon Jeong
23(5) 352-360, 2019
천승재 Seung-jae Chon , 서주노 Joo-no Sur , 정성훈 Seong-hoon Jeong
DOI: JANT Vol.23(No.5) 352-360, 2019
This paper proposes a docking assessment algorithm for an autonomous underwater vehicles (AUVs) with sensor uncertainties. The proposed algorithm consists of two assessments, state assessment and probability assessment. The state assessment verifies the reachability by comparing forward distance to the docking station with expected distance to reach same depth as the docking station and necessity for correcting its route by comparing calculated inaccessible areas based on turning radius of the AUV to position of the docking station. When the AUV and the docking station is close enough and the state assessment is satisfied, the probability assessment is conducted by computing success probability of docking based on the direction angle, relative position to the docking station, and sensor uncertainties of the AUV. The final output of the algorithm is decided by comparing the success probability to threshold whether to try docking or to correct its route. To verify the validation of the suggested algorithm, the scenario that the AUV approaches to the docking station is implemented through Matlab simulation.
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Design of Automatic Model Verification for System Integration Laboratory
양승구 Seung-gu Yang , 조연제 Yeon-je Cho , 조경용 Kyoung-yong Jo , 류창명 Chang-myung Ryu
23(5) 361-366, 2019
양승구 Seung-gu Yang , 조연제 Yeon-je Cho , 조경용 Kyoung-yong Jo , 류창명 Chang-myung Ryu
DOI: JANT Vol.23(No.5) 361-366, 2019
In developing the avionics system, a system integration laboratory (SIL) is established to verify the function and interworking of individual components. In case of individual verification of SIL's components and system integration, a SIL model that simulates the function and interworking of each equipment is developed and used. A SIL model shall be pre-verified against all data defined in the interface control document (ICD) before interworking with the actual equipment and reverified even when the ICD changes or functions change. However, if the verification of the SIL model is performed manually, the verification of the individual SIL model takes considerable time. For this reason, selective regression tests are often performed to determine a impact of SIL models on ICD changes and some functional changes. In this paper, we designed SIL model verification automation method to perform regession test by reducing verification time of SIL model and verify the usefulness of verification automation design by developing SIL model verification automation tool.
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The Efficient Utilization of the Image Recognition System using CAN Communications in the Ship
홍성화 Sung-hwa Hong , 이성렬 Seong-real Lee
23(5) 367-372, 2019
홍성화 Sung-hwa Hong , 이성렬 Seong-real Lee
DOI: JANT Vol.23(No.5) 367-372, 2019
With the development of various IT technologies, data generated in the ship can be controlled through CAN communication, autonomous operation, and information provision in various situation. In addition, electronic navigation vessels with various functions have emerged, and navigation and communication equipment used in these vessels are mainly following the NMEA standard. Currently, NMEA-0183 is still mainly used, but more efficient multimedia transmission processing method is needed for multimedia transmission and USN equipment compatible using NMEA-2000 standard. Furthermore, Ethernet-based ship control is required. However, this paper proposes a multimedia transmission scheme to be smoothly linked with existing ship devices by utilizing CAN communication that can be easily used in the ship.
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Utilization of AeroMACS Infrastructure for Airports and Airlines
임인규 In-kyu Lim , 강자영 Ja-young Kang
23(5) 373-379, 2019
임인규 In-kyu Lim , 강자영 Ja-young Kang
DOI: JANT Vol.23(No.5) 373-379, 2019
AeroMACS spectrum is a national resource internationally allocated by ITU at WRC-07. AeroMACS is an airport broadband mobile communication infrastructure based on WiMAX-based IEEE 802.16e that enables real-time video, graphics, voice, and high-speed data transmission. With the approval of ICAO's development technology standards in 2008, 50 airports in 11 countries have already completed the testing of D-TAXI or A-SMGCS technology using the AeroMACS infrastructure in 2019, starting in the United States in 2009. With many advantages in safety and convenience in terrestrial telecommunications operations, the system is becoming an area of performance improvement for airport operations in accordance with ICAO's ASBU plan. This paper examines the current status of domestic development of AeroMACS and lists service areas applicable to airlines and operators. It also seeks to promote safe and efficient next-generation airport mobile communication system services by presenting feasible partners management in the mobile area and use of aircraft communication systems for active technology development.
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Analysis of Departing Passengers’ Dwell Time using Clustering Techniques
안덕배 Deok-bae An , 김휘양 Hui-yang Kim , 백호종 Ho-jong Baik
23(5) 380-385, 2019
안덕배 Deok-bae An , 김휘양 Hui-yang Kim , 백호종 Ho-jong Baik
DOI: JANT Vol.23(No.5) 380-385, 2019
This paper is concerned with departure passengers’ dwell time analysis using real system data. Previous researches emphasize the importance of dwell time analysis from perspective of airport terminal planning and non-aeronautical revenue. However, short-term airport operation using passengers’ dwell time is considered impossible due to absence of passengers’ behavior data. Recently, in accordance with the wave of smart airport, world leading airports are systematically collecting passenger data. So there is high possibility of analyzing passengers’ dwell time with the data stacked in the airport database. We conducted dwell time analysis using data from Incheon Int’l airport. In order to handle passenger data, we adapted clustering algorithm which is one of data mining techniques. As a clustering result, passengers are divided into 3 clusters. One is the cluster for passengers whose dwell time is relatively short and who tend to spend longer time in the airside. Another is the cluster for passengers who have near 3 hours dwell time. The other is the cluster for passengers whose total dwell time is extremely long.
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Analysis of the Directional Group Delay of the Antenna for the Radio Navigation System
정성훈 Sunghun Jung , 설동민 Dong-min Seol , 이철수 Chul-soo Lee , 선중규 Jung-kyu Sun
23(5) 386-391, 2019
정성훈 Sunghun Jung , 설동민 Dong-min Seol , 이철수 Chul-soo Lee , 선중규 Jung-kyu Sun
DOI: JANT Vol.23(No.5) 386-391, 2019
This paper presents analysis results for the effect of the directional group delay of the antenna to implement a precision radio navigation system. The analysis was conducted through antenna simulation and test, and the test was performed in an anechoic chamber. The directional group delay of the antenna was calculated in phase-based analysis method. The results showed that a variation of up to 7.7ns in group delay occurred per antenna direction. The group delay variation from the analysis is 2.31 meters when converted into distance. It was tested using a real radio navigation system based on the time of arrival (TOA). The test verified the distance variation of 2.1 meters, and this value is similar to those obtained from the simulation and chamber test analysis.
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Wireless TDD Time Synchronization Technique Considering the Propagation Delay Between Mobile Vehicles
부정일 Jung-il Boo , 하정완 Jeong-wan Ha , 김강산 Kang-san Kim , 김복기 Bokki Kim
23(5) 392-399, 2019
부정일 Jung-il Boo , 하정완 Jeong-wan Ha , 김강산 Kang-san Kim , 김복기 Bokki Kim
DOI: JANT Vol.23(No.5) 392-399, 2019
In this paper, we have studied wireless time division duplex(TDD) time synchronization technique considering the propagation delay between mobile vehicles. The existing IEEE 1588 precision time protocol(IEEE 1588 PTP) algorithm was applied and the time synchronization between the two nodes was achieved through the propagation delay and clock offset time correction calculated between master slave nodes during wireless TDD communication. The time synchronization process and procedure of IEEE 1588 PTP algorithm were optimized, thereby reducing the propagation delay error sensitivity for real-time moving vehicles. The sync flag signal generated through the time correction has a time synchronization accuracy of max +252.5 ns within 1-symbol(1.74 M symbol/sec, ±287.35ns) through test and measurement, and it was confirmed that the time synchronization between master slave nodes can be achieved through sync flag signal generated during GPS disturbance.
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Shadow Reconstruction Based on Intrinsic Image and Multi-Scale Gamma Correction for Aerial Image Analysis
박기홍 Ki-hong Park
23(5) 400-407, 2019
박기홍 Ki-hong Park
DOI: JANT Vol.23(No.5) 400-407, 2019
In this paper, the shadow detection and reconstruction method are proposed using intrinsic image, which does not change the essential characteristics under the influence of various illuminance, and multi-scale gamma correction. The shadow detection was estimated by the pixel change information between a grayscale and an intrinsic image of the color image, and the brightness of the image were adjusted by gamma correction in the shadow restoration process. Multi-scale gamma correction is performed for each channel of a color image due to the fact that the saturation can be changed by nonlinear adjustment to individual pixel values. Multi-scale gamma values are estimated based on the information of the crossed edge between shadows and non-shadowed regions in the color image, as a result, the shadows are reconstructed by correcting different region features with multi-scale gamma values. Experimental results show that the proposed method effectively reconstructs shadows in a single natural image.
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Safety Distance Visualization Tool for LTE-Based UAV Positioning in Urban Areas
이하림 Halim Lee , 강태원 Taewon Kang , 서지원 Jiwon Seo
23(5) 408-414, 2019
이하림 Halim Lee , 강태원 Taewon Kang , 서지원 Jiwon Seo
DOI: JANT Vol.23(No.5) 408-414, 2019
We developed a surveillance tool for collision avoidance of unmanned aerial vehicles (UAVs) in urban areas. In our tool, users can visualize the safety distance on the actual 3D map of urban area. The estimated positions of UAVs are assumed to be obtained based on the long-term evolution (LTE) signals. The safety distance is defined to include two or more signals with bias. The safety distance calculation method used in this paper enables simulation similar to the actual urban areas where signals are frequently biased due to multipath. In the simulation, the parameters were set based on the measured values, and the change of the safety distance according to the number of faulty signals was simulated. As a result, increasing the number of faulty signals led to a longer safety distance as expected.
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Design of Bent-Slotted High-Sensitivity Microstrip Patch Permittivity Sensor Antenna
여준호 Junho Yeo , 이종익 Jong-ig Lee
23(5) 415-423, 2019
여준호 Junho Yeo , 이종익 Jong-ig Lee
DOI: JANT Vol.23(No.5) 415-423, 2019
In this paper, a design method for a high-sensitivity microstrip patch sensor antenna (MPSA) loaded with a bent-slot was studied for the permittivity measurement. The bent-slot similar to a single-ring complementary split ring resonator was added along a radiating edge of the patch in order to enhance the sensitivity to the permittivity. The sensitivity of the proposed MPSA was compared with that of a conventional rectangular MPSA and a thin rectangular-slotted MPSA. Three MPSAs were designed and fabricated on a 0.76-mm-thick RF-35 substrate so that the input reflection coefficient would resonate at 2.5 GHz in the absence of the superstrate under test. When five different Taconic substrates with a relative permittivity ranging from 2.17 to 10.2 were used as the superstrate under test, experiment results show that the sensitivity of the proposed MPSA, which is measured by the shift in the resonant frequency of the input reflection coefficient, is 4.1 to 6.1 times higher than that of the conventional MPSA.
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An Output Feedback Predictive Control for Stabilizing a System With Multiple Delayed Inputs
양장훈 Janghoon Yang
23(5) 424-429, 2019
양장훈 Janghoon Yang
DOI: JANT Vol.23(No.5) 424-429, 2019
The evolution of networking technology such as commercialization of 5G systems provides foundation for information exchange and control of systems over the network. In addition, importance of controlling a system with delay is increasing significantly, since various phenomena in the network are associated with delay. In this paper, with a predictive control which has been studied for designing a controller with low complexity, we propose a novel predictive control for a system with multi-inputs such that it can keeps the complexity almost the same regardless of the number of inputs and degree of delay. The asymptotic stability of the proposed control with a static output feedback is also proved. The numerical simulation shows that the proposed method is superior in complexity and the performance of finding feasible controllers to the existing predictive control and a conventional method based on augmented states.
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PCB Pattern Antenna of 920 MHz Band for Marine IoT Services
이성렬 Seong-real Lee
23(5) 430-436, 2019
이성렬 Seong-real Lee
DOI: JANT Vol.23(No.5) 430-436, 2019
It is needed to develop an antenna with features of subminiature, light weight and multi-band operation for the variaty services in maritime and industrial fields. The PCB pattern antenna is one of the appropreiate antennas solving these requirements. In this research, the design and fabrication of the PCB pattern antenna operating on the single band of 920 MHz are investigated. The final goal is that the development of the dual band PCB pattern antenna operating on 260 MHz and 920 MHz, which is based on the proposed antenna. It is evident that the performance in the frequencies of 902 MHz, 915 MHz and 928 MHz among of 920 MHz ISM band is better than that in other frequencies. It is also confirmed that the differences of the voltage standing wave ratio, return loss, gain and efficiency between three frequencies are less than 5%. It is expected that the development of communication link of 5-10 km is possible when the induced results are applied into the low power wide area (LPWA) network desinged by the rule of -30 dB sensitivity.
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TOA-Based Ranging Method using CRS in LTE Signals
강태원 Taewon Kang , 이하림 Halim Lee , 서지원 Jiwon Seo
23(5) 437-443, 2019
강태원 Taewon Kang , 이하림 Halim Lee , 서지원 Jiwon Seo
DOI: JANT Vol.23(No.5) 437-443, 2019
In this paper, a new algorithm for the calculation of the range between an LTE base station (BS) and a user equipment (UE) using time-of-arrival (TOA) measurements of LTE signals is proposed. First, the cell identity (cell ID) of the received signal is acquired using the primary synchronization signal (PSS) and secondary synchronization signal (SSS) to identify the BS transmitted the signal. The proposed algorithm exploits the cell-specific reference signal (CRS), the reference sequence inserted in commercial LTE signals, to estimate the time delay using 2D cross-correlation. The obtained TOA estimations can be used to calculate the range employed from the known BS location. The performance of the proposed algorithm is evaluated with the experiment performed using real LTE signals transmitted from the commercial BS.
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Protection Design for EMI and Indirect Lightning Effect for RS-170a Video Signal
조성진 Seong-jin Cho , 심용기 Yong-gi Sim , 김성훈 Sung-hun Kim , 박준현 Jun-hyun Park
23(5) 444-451, 2019
조성진 Seong-jin Cho , 심용기 Yong-gi Sim , 김성훈 Sung-hun Kim , 박준현 Jun-hyun Park
DOI: JANT Vol.23(No.5) 444-451, 2019
In this paper, we introduce the design consideration of the EMI and lightning induced transient protection circuit for RS-170a video signal on the avionics equipment. Avionics equipment is subject to the risk of malfunction or physical damage due to indirect lightning effect from lightning strike or electromagnetic interference from external environment. So in order to protect the avionics equipment from these effects, we should analyze the effect of electromagnetic interference and lightning strike on aircraft and apply protection design for each avionics device, but protection circuit may cause signal distortion if signal level is low and frequency is high. In this paper, we introduce common protection design for EMI and indirect lightning effect, and consideration for minimize signal distortion caused by protection circuit for RS-170a. In addition, we show some example of improvements to the actual equipment design using consideration discussed in this paper.
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PCM Encoder Structure for Real-time Updating of Telemetry System Parameters
박유광 Yu-kwang Park , 윤원주 Won-ju Yoon
23(5) 452-459, 2019
박유광 Yu-kwang Park , 윤원주 Won-ju Yoon
DOI: JANT Vol.23(No.5) 452-459, 2019
In this paper, we describe a PCM encoder structure that can update the telemetry system parameters in real time. In the PCM encoder, an analog signal control unit for FPGA, flash memory, and sensor data acquisition was constructed. UART communication, analog signal control, flash memory control, and frame generation are possible through logic inside FPGA of PCM encoder. UART communication allows the PC to transmit parameter data to the PCM encoder, and flash memory is controlled to update the parameter of the telemetry system in real time and finally the frame is formed. Simulation and verification were performed to confirm whether the parameter data is updated in real time, and the proposed structure was used to construct a telemetry system with enhanced flexibility and convenience.
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Structural Improvement for Crack of Integrated Circuit in Single Board Computer by Structure Analysis
류정민 Jeong-min Ryu , 이용준 Yong-jun Lee , 손권일 Kwonil Sohn
23(5) 460-465, 2019
류정민 Jeong-min Ryu , 이용준 Yong-jun Lee , 손권일 Kwonil Sohn
DOI: JANT Vol.23(No.5) 460-465, 2019
In this study, we aim to derive a solution from the structural analysis for electrical failure of single board computers for computing navigation information. By analyzing the characteristic factor, we identify that crack occur on the central processing unit board due to a certain structural problem, and that the physical effect by the crack make communication function be impossible to perform, which it causes booting error. In order to find the location of excessive stress causing the crack, structural analysis for the single board computer is done. From the structural analysis, the areas where stress concentration occurs are identified, and improvement methods changing the structures are developed. As a result, we shows that stresses are reduced entirely on the stress distribution for the improved structure. In addition, heat analysis shows that changing the structure to reduce stresses is not affect to the heat radiation, and the thermal resistance of the actual equipment is verified by measuring the temperature of the heat sink applied with the improved structure.
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An Exploratory Study on the Designation of Disaster Management Resources
김동명 Dong-myung Kim , 정종수 Chong-soo Cheung
23(5) 466-472, 2019
김동명 Dong-myung Kim , 정종수 Chong-soo Cheung
DOI: JANT Vol.23(No.5) 466-472, 2019
The purpose of this study is to examine the problems of disaster management resources needed for disaster occurrence, to find ways to improve them, and to utilize them in the future. For this research, theoretical background was established through previous research data on disaster management resources. Disaster management resources prescribed in the Basic Act on Disaster and Safety Management, Classification of Disaster Management Resources and System Use, and Joint Utilization Standards of Disaster Management Resources were analyzed to identify problems and to suggest improvements. As a result of the research, clarity on disaster management resources was secured through literature research and analysis of laws and regulations. By suggesting ways to utilize the manpower and material resources designated by the Emergency Preparedness Resource Management Act in the event of various disasters, it was confirmed that the disaster management resources could be utilized in the right place for various disaster situations.
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Smart Home Service System Considering Indoor and Outdoor Environment and User Behavior
김재정 Jae-jung Kim , 김창복 Chang-bok Kim
23(5) 473-480, 2019
김재정 Jae-jung Kim , 김창복 Chang-bok Kim
DOI: JANT Vol.23(No.5) 473-480, 2019
The smart home is a technology that can monitor and control by connecting everything to a communication network in various fields such as home appliances, energy consumers, and security devices. The Smart home is developing not only automatic control but also learning situation and user's taste and providing the result accordingly. This paper proposes a model that can provide a comfortable indoor environment control service for the user's characteristics by detecting the user's behavior as well as the automatic remote control service. The whole system consists of ESP 8266 with sensor and Wi-Fi, Firebase as a real-time database, and a smartphone application. This model is divided into functions such as learning mode when the home appliance is operated, learning control through learning results, and automatic ventilation using indoor and outdoor sensor values. The study used moving averages for temperature and humidity in the control of home appliances such as air conditioners, humidifiers and air purifiers. This system can provide higher quality service by analyzing and predicting user's characteristics through various machine learning and deep learning.
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Implementation of the Integrated Monitoring System for Improvement of Production Environment
윤재현 Jae-hyeon Yoon , 장상길 Sang-gil Jang , 정종문 Jong-mun Jung , 고봉진 Bong-jin Ko
23(5) 481-486, 2019
윤재현 Jae-hyeon Yoon , 장상길 Sang-gil Jang , 정종문 Jong-mun Jung , 고봉진 Bong-jin Ko
DOI: JANT Vol.23(No.5) 481-486, 2019
Smart Factory requires real-time monitoring and analysis of all process processes for optimal production environment. Monitoring system for data collection from various sensors is necessary to make all production processes automatic. By storing and analyzing the collected data, we can check whether there are any signs of abnormalities in any machine or equipment. Thus, in this paper, an integrated monitoring system for smart factory incorporating a working environment monitoring system and an automatic storage system of measurement values was implemented. By using the automatic storage system of measurement values, it is possible to carry out reliable inspection in any place without misentry. Also, through working environment monitoring system using LoRa, production environments such as temperature, humidity and atmospheric pressure can be monitored in real time.
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