• Journal of The Korean Society of Agricultural Engineers
• /
• v.63 no.4
• /
• pp.23-32
• /
• 2021

For agricultural water management, it is essential to establish the digital infrastructure data such as agricultural watershed, irrigated area and canal network in rural areas. Approximately 70,000 irrigation facilities in agricultural watershed, including reservoirs, pumping and draining stations, weirs, and tube wells have been installed in South Korea to enable the efficient management of agricultural water. The total length of irrigation and drainage canal network, important components of agricultural water supply, is 184,000 km. Major problem faced by irrigation facilities management is that these facilities are spread over an irrigated area at a low density and are difficult to access. In addition, the management of irrigation facilities suffers from missing or errors of spatial information and acquisition of limited range of data through direct survey. Therefore, it is necessary to establish and redefine accurate identification of irrigated areas and canal network using up-to-date high resolution images. In this study, previous existing data such as RIMS (Rural Infrastructure Management System), smart farm map, and land cover map were used to redefine irrigated area and canal network based on appropriate image data using satellite imagery, aerial imagery, and drone imagery. The results of the building the digital infrastructure in rural areas are expected to be utilized for efficient water allocation and planning, such as identifying areas of water shortage and monitoring spatiotemporal distribution of water supply by irrigated areas and irrigation canal network.

• International Journal of Computer Science & Network Security
• /
• v.23 no.1
• /
• pp.78-88
• /
• 2023

Medication safety and medicine delivery challenge the well-being of the elderly and the management of the elderly center. With the outbreak of COVID-19, the elderly in the care center were challenged by the inconvenience of the medication restocking. The purpose of this paper accentuates the importance of the design and development of an UAV-based Smart Medicine Case (UAV-SMC) to improve the performance of medication management and medicine delivery in the elderly center. The researchers came up with the design of UAV-SMC in the light of the UAV and IoT technology to improve the performance of both Medication Practice Management (MPM) and Low Inventory Detection and Delivery (LIDD). Based on the result, with UAV-SMC, the performance of both MPM and LIDD was significantly improved. The UAV-SMC improves the efficacy of medication management in the elderly center by 26.97 to 149.83 seconds for each medication practice and 9.03 mins for each time of medicine delivery in Subang Jaya Malaysia. This paper only investigates the adoption of UAV-SMC in the content of elderly center rather than other industries. The authors consider integrating the UAV-SMC with the e-pharmacy system in the future. In conclusion, the UAV-SMC has significantly improved the medication management and guard the safety of elderly and caretaker in the elderly in the post-pandemic times.

• The Journal of the Korea Contents Association
• /
• v.19 no.11
• /
• pp.111-121
• /
• 2019

Recently, through the services that use drones at fire sites to deliver on-site and road conditions into the situation room and life-saving activities or the deliveries of first aid outfits at the accident scenes that are inaccessible to humans, there are more and more cases of dealing with emergency situations. Therefore, by studying the service design using drones in the initial stage of response to fires in dense residential areas, this study was intended to reify the service design area of the response stage, including the dispatch of fire sites and the fire suppression. To do this, through literature researches, research directions were explored by examining the concept and process review of service design, and by analyzing the application cases using service design. In order examine the validity of this study, a one-on-one interview was conducted to identify the use and problems of drones among incumbent firefighters, and identified the applicability of drones to fire sites by targeting drone experts. Field research was conducted to identify the location and distance of road conditions, site conditions, and 119 safety centers, by making Yongsan-gu, the most vulnerable area to fire in Seoul, as a research sample. And, among the methodologies of service design, Persona and Customer Journey Map were prepared and Insight was derived, by using virtual scenarios for the experience values and behavior analyses of the interested parties. Through these processes, this researcher intended to present the fire-response service design and help establish the direction of service design in the initial stages of fire in Korea.

• The Korean Journal of Air & Space Law and Policy
• /
• v.30 no.2
• /
• pp.373-401
• /
• 2015

The UAV(Unmanned Aerial Vehicle, Drone) technology has been undergoing rapid progress, accompanied with a growth in the market. However, domestic industry standards and technology lag behind such progress happening on the international scene, and in particular in developed countries. Related regulations are also deemed lacking to address the issues that arise with such developments. Meanwhile, as the rise of UAV technology is a fairly recent phenomenon, the gap between Korea and developed countries is not too big. As this technology has high relevance to information and communication technologies, it also offers ample leeway for Korea to catch up in the field of UAV. As such, this paper seeks to provide a survey of the overall technology, market and regulations concerning UAV to identify possible measures on how to address any issues that may arise through proper policies. Due to the progress made in the field of UAV technology and increased penetration rate, striking a right balance between putting in place a proper regulatory system and establishing policies that foster growth in the field has risen as a very important issue. While the importance of establishing a legal system that helps prevent possible risks is indeed important, it must also be acknowledged that excessive regulation can also hinder technological progress. This, in turn would stagnate the market and dampen the entrepreneurial spirit in the society. In the case of new, practical technologies such as UAV, a prompt establishment of regulatory systems and policy measures in terms of policies is a requisite. In brief, in order to promote progress in the UAV industry and at the same time, for public safety and the protection of privacy, there should be an appropriate level on the easing and tightening of the regulation.

• Journal of Korea Water Resources Association
• /
• v.55 no.8
• /
• pp.623-634
• /
• 2022

Due to river maintenance projects such as the creation of hydrophilic areas around rivers and the Four Rivers Project, the flow characteristics of rivers are continuously changing, and the risk of water quality accidents due to the inflow of various pollutants is increasing. In the event of a water quality accident, it is necessary to minimize the effect on the downstream side by predicting the concentration and arrival time of pollutants in consideration of the flow characteristics of the river. In order to track the behavior of these pollutants, it is necessary to calculate the diffusion coefficient and dispersion coefficient for each section of the river. Among them, the dispersion coefficient is used to analyze the diffusion range of soluble pollutants. Existing experimental research cases for tracking the behavior of pollutants require a lot of manpower and cost, and it is difficult to obtain spatially high-resolution data due to limited equipment operation. Recently, research on tracking contaminants using RGB drones has been conducted, but RGB images also have a limitation in that spectral information is limitedly collected. In this study, to supplement the limitations of existing studies, a hyperspectral sensor was mounted on a remote sensing platform using a drone to collect temporally and spatially higher-resolution data than conventional contact measurement. Using the collected spatio-temporal hyperspectral images, the tracer concentration was calculated and the transverse dispersion coefficient was derived. It is expected that by overcoming the limitations of the drone platform through future research and upgrading the dispersion coefficient calculation technology, it will be possible to detect various pollutants leaking into the water system, and to detect changes in various water quality items and river factors.

• Journal of Korea Water Resources Association
• /
• v.56 no.4
• /
• pp.235-243
• /
• 2023

Due to the revision of the River Act and the enactment of the Act on the Investigation, Planning, and Management of Water Resources, a regular bed change survey has become mandatory and a system is being prepared such that local governments can manage water resources in a planned manner. Since the topography of a bed cannot be measured directly, it is indirectly measured via contact-type depth measurements such as level survey or using an echo sounder, which features a low spatial resolution and does not allow continuous surveying owing to constraints in data acquisition. Therefore, a depth measurement method using remote sensing-LiDAR or hyperspectral imaging-has recently been developed, which allows a wider area survey than the contact-type method as it acquires hyperspectral images from a lightweight hyperspectral sensor mounted on a frequently operating drone and by applying the optimal bandwidth ratio search algorithm to estimate the depth. In the existing hyperspectral remote sensing technique, specific physical quantities are analyzed after matching the hyperspectral image acquired by the drone's path to the image of a surface unit. Previous studies focus primarily on the application of this technology to measure the bathymetry of sandy rivers, whereas bed materials are rarely evaluated. In this study, the existing hyperspectral image-based water depth estimation technique is applied to rivers with vegetation, whereas spatio-temporal hyperspectral imaging and cross-sectional hyperspectral imaging are performed for two cases in the same area before and after vegetation is removed. The result shows that the water depth estimation in the absence of vegetation is more accurate, and in the presence of vegetation, the water depth is estimated by recognizing the height of vegetation as the bottom. In addition, highly accurate water depth estimation is achieved not only in conventional cross-sectional hyperspectral imaging, but also in spatio-temporal hyperspectral imaging. As such, the possibility of monitoring bed fluctuations (water depth fluctuation) using spatio-temporal hyperspectral imaging is confirmed.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.25 no.1
• /
• pp.56-76
• /
• 2022

This study shared with community mapping participants spatial analysis information, collected using smart devices, to give them an opportunity to objectively review their opinions. The study examined the impact of sharing such spatial information on residents' decision-making and perceptions. Yeongju-dong in Jung-gu district of Busan Metropolitan City, South Korea was selected for the case study; community mapping was carried out in Yeongju-dong to identify hazardous areas to improve pedestrian safety of primary school students. The community mapping participants drew a preliminary hazard map based on their experience and perception. Then, they drew a second hazard map after being given spatial information on pedestrian safety installations and pedestrian flow collected with smart devices including drones and sensors. Numerous changes in ranking across various sections occurred when the two maps were compared. There was a climb in the ranking of areas where the pedestrian flow was higher and lacked safety installations based on objective measurements over the perceptions of the participating people. Furthermore, according to a survey conducted among the participants, the provision of spatial analysis information using smart devices during community mapping process not only helped them recognize local community problems, but also raised their expectations that their submitted opinions would be reflected in policies. Moreover, the participants demonstrated increased self-confidence and faith in themselves as they were able to have more trust in the outcome they created.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.13 no.3
• /
• pp.509-516
• /
• 2018

TCP is a well-known communication protocol which is widely used for reliable message transmissions. The urgent mechanism of TCP plays a key role to transmit messages with a high priority. If a high priority message occurs at the transmitting node, the urgent mechanism informs the receiving node about the presence of a high priority message prior to its transmission so that the receiving node can be prepared for handling this message in advance. This implies that the existing urgent mechanism of TCP does not guarantee an immediate or faster delivery of the high priority message itself. Therefore, the ability of priority-based transmission is required on TCP not only to ensure reliable transmissions of normal messages but also to offer a differentiated service according to the priority of message. This paper presents a priority-based transmission algorithm over TCP using a priority queue in a multi-threaded environment. The effectiveness of the proposed algorithm is explored using an experimental setup in which various messages with different priority levels are transmitted.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.17 no.5
• /
• pp.199-208
• /
• 2017

Lithium polymer batteries are used in energy storage systems (ESS), electric vehicles (EVs), etc. due to their high safety, fast charging and long lifecycle, and now they are used in agricultural drones. However, when overcharging and overdischarging, the lithium-polymer battery is destroyed in the gap structure in the lithium-ion battery and the battery life is reduced. In order to prevent overcharge and overdischarge, uneven cell voltage Cell balancing system is needed. In this paper, a fuzzy controller suitable for nonlinear systems is proposed by detecting the unbalanced cells by detecting the voltage difference between charging and discharging of each cell, and suggesting the applied cell balancing algorithm. In this paper, we have designed the cell balancing of the battery pack of agricultural drones by fuzzy control and it is designed for equal control between cells. As a final result, we checked whether cell balancing is good, and when there are two cells, Cell balancing was confirmed. We tested whether it could be used for other products. As a result, we confirmed that cell balancing is good regardless of the number of cells used.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.42 no.4
• /
• pp.855-863
• /
• 2017

Because Li-ion battery and Li-Polymer battery have high-energy storage density, they are used for various electronic devices such as electronic cigarette, electronic bicycle, drone, second battery, even golf cart and electronic car. Recently, however, battery explosion is sometimes occurring on electronic devices using Li-ion battery and is becoming serious as bodily harm is breaking out due to explosion. For this, this paper described the Li-ion Battery's operating principles and verified the cause of explosion by overload tests caused by the high-energy storage density. According to the these experiments, we conducted a study to develope scanning techniques of fire and safety measures.