• Journal of Convergence for Information Technology
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• v.11 no.4
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• pp.26-34
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• 2021

In the era of the Fourth Industrial Revolution, the future battlefield will carry out multi-area operations with hyper-connected, high-speed and mobile systems. In order to prepare for changes in the future, the Korean military intends to develop various weapons systems and form a multi-layer tactical network to support On The Move communication. However, current tactical networks are limited in support of On The Move communications. In other words, the operation of multi-beam antennas is necessary to efficiently construct a multi-layer tactical network in future warfare. Therefore, in this paper, we look at the need for multi-beam antennas through the operational scenario of a multi-layer tactical network. In addition, based on development consideration factors, features of rotary-wing and fixed-wing aircraft, we present the location and operation of airborne relay drone installations of multi-beam antennas.

• Journal of the Institute of Convergence Signal Processing
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• v.22 no.4
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• pp.179-184
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• 2021

Along with the development of the fourth industry, the public sector has increasingly paid more attention to search using drones and real-time monitoring, for various goals. The drones are used and researched to complete a variety of searching and monitoring missions, including search for missing persons, security, coastal patrol and monitoring, speed enforcement, highway and urban traffic monitoring, fire and wildfire monitoring, monitoring of illegal fishing in reservoirs and protest rally monitoring. Police stations, fire departments and military authorities, however, concentrate on the hardware part, so there are little research on efficient communication systems for the real-time monitoring of data collected from high-performance resolution and infrared thermal imagining cameras, and analysis programs suitable for special missions. In order to increase the efficiency of drones with the searching mission, this paper, therefore, attempts to propose an image analysis technique to increase the precision of search by producing image data suitable for searching missions, based on images obtained from drones and provide the foundation for improving relevant policies and establishing proper platforms, based on actual field cases and experiments.

• Journal of Broadcast Engineering
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• v.27 no.6
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• pp.936-939
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• 2022

As air combat system technologies developed in recent years, the development of air defense systems is required. In the operating concept of the anti-aircraft defense system, selecting an appropriate armament for the target is one of the system's capabilities in efficiently responding to threats using limited anti-aircraft power. Much of the flying threat identification relies on the operator's visual identification. However, there are many limitations in visually discriminating a flying object maneuvering high speed from a distance. In addition, as the demand for unmanned and intelligent weapon systems on the modern battlefield increases, it is essential to develop a technology that automatically identifies and classifies the aircraft instead of the operator's visual identification. Although some examples of weapon system identification with deep learning-based models by collecting video data for tanks and warships have been presented, aerial vehicle identification is still lacking. Therefore, in this paper, we present a model for classifying fighters, helicopters, and drones using a convolutional neural network model and analyze the performance of the presented model.

• The Journal of the Acoustical Society of Korea
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• v.43 no.1
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• pp.29-38
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• 2024

The Matched Field Processing (MFP) is an estimation method for a source range and depth based on the prediction of sound propagation. However, as the frequency increases, the prediction inaccuracy of sound propagation increases, making it difficult to estimate the source position. Recently proposed, the Frequency-Difference Matched Field Processing (FD-MFP) is known to be robust even if there is a mismatch by applying a frequency-difference autoproduct extracted from the auto-correlation of a high frequency signal. In this paper, in order to evaluate the performance of the FD-MFP using a horizontal line array, simulations were conducted in the environment of the East Sea of Korea. In the area of Bottom Bounce (BB) and Convergence Zone (CZ) where detection of a sound source is possible at a long range, and the results of localization were analyzed. According to the the FD-MFP simulations of horizontal line array, the accuracy of localization is similar or degraded compared to the conventional MFP due to diffracted field and mismatch of sound speed. There was no clear result from the simulations conforming that the FD-MFP was more robust to mismatch than the conventional MFP.

• Journal of Internet of Things and Convergence
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• v.10 no.3
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• pp.19-24
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• 2024

Recent advances in large-scale data processing technologies such as big data, cloud computing, and artificial intelligence have increased the demand for high-performance storage devices in data centers and enterprise environments. In particular, the fast data response speed of storage devices is a key factor that determines the overall system performance. Solid state drives (SSDs) based on the Non-Volatile Memory Express (NVMe) interface are gaining traction, but new bottlenecks are emerging in the process of handling large data input and output requests from multiple hosts simultaneously. SSDs typically process host requests by sequentially stacking them in an internal queue. When long transfer length requests are processed first, shorter requests wait longer, increasing the average response time. To solve this problem, data transfer timeout and data partitioning methods have been proposed, but they do not provide a fundamental solution. In this paper, we propose a dual queue based scheduling scheme (DQBS), which manages the data transfer order based on the request order in one queue and the transfer length in the other queue. Then, the request time and transmission length are comprehensively considered to determine the efficient data transmission order. This enables the balanced processing of long and short requests, thus reducing the overall average response time. The simulation results show that the proposed method outperforms the existing sequential processing method. This study presents a scheduling technique that maximizes data transfer efficiency in a high-performance SSD environment, which is expected to contribute to the development of next-generation high-performance storage systems

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.6
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• pp.965-972
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• 2022

This is a basic study to establish marine activity criteria based on the seakeeping performance of less than 10-tons fishing vessels. These vessels account for approximately 95% of Korea's currently registered fishing vessels, and accidents and loss of life are also occurring during marine activities such as navigation, and fishing. Accordingly, the Ministry of Oceans and Fisheries has set a regulation of vessel traf ic control to restrict the operation of fishing vessels when the high seas watch takes effect, but it is applied equally without criteria according to the ship ton level and wave height; therefore, many differences may exist in ship fluctuations. Because the fluctuation of the ship owing to the wave height can be a factor in marine accidents by reducing the sense of boarding and performance of equipment, the seakeeping performance must be reviewed during waves to secure safe marine activities such as navigation and fishing. However, the review for the fishing vessel of established marine activity criteria based on the seakeeping performance is insufficient. Accordingly, the seakeeping performance was evaluated for a 10-ton class (G/T 9.77 tons) fishing vessel in Korea, and the level of marine activity according to the significant wave height and ship speed was interpreted by applying the operation and survival of the established seakeeping performance criteria. The analysis results indicated that the roll of the ship exceeded the operation criteria from 0.4m and the survival criteria from 2.2m. The pitch of the ship exceeded the operation criteria from 1.7m and did not exceed the survival criteria until 3.0m. However, the rolling exceeding the survival criteria from 2.2m may not be safe. Therefore, fishing vessels with less than 10-tons can leave before the high seas watch takes effect. However, they did not satisfy the criteria for evaluating the performance of the sea in relation to marine activities. Although this study was limitedly evaluated for 10-ton fishing vessels, it is expected to be of great help in preparing marine activity criteria.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.431-436
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• 2020

Information service organizations that provide science and technology information with a relatively short information life cycle for free or paid are in need of reflecting rapidly changing user needs and behaviors and grafting the latest technologies. The purpose of this study is to derive improvements for each system by comparing and analyzing general recognition of science and technology information users' domestic and foreign science and technology information sites and importance by science and technology information attributes. A total of 816 users of science and technology information participated in the online survey, and the collected data were analyzed by quantitative methods including IPA (Importance Performance Analysis) technique. The importance was evaluated by the impact value calculated through regression analysis. As a result of data analysis, the general recognition of users on science and technology information sites was relatively high in national science and technology information services, and Google Scholar and Science Direct were also high. Google Scholar was found to have more strength than improvement. A better understanding of the user's preferred system is a good driving force for improving the lack of existing systems. It is necessary to improve the information retrieval of the science and technology information service system, that is, to improve the search speed and functions, and also to improve the user interface with improved convenience and usability.

• Journal of Conservation Science
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• v.31 no.2
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• pp.125-130
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• 2015

Specific techniques and materials in conservation of traditional lacquer has not been transmitted. This study aims to compare the basic characteristics of the filler which used in the base layer of lacquer conservation. Tohoe(a mixture of lacquer and Clay) and the three kinds of additives which is mixed with Tohoe and Goksu(a mixture of lacquer, wood powder and rice starch) are estimated in drying rate, impact resistance, abrasion. Among those samples, the more amount of clay causes fast dryness speed and worse cracks on the surface. The impact resistance is weakened at high amount of clay. There is no significant differences of impact resistance between both additives that is mixed with the samples and additives. The samples that are mixed with Goksu and additives show high impact resistance. In the polishing test, the more amount of filling powders show higher grinding degree and the sample that are mixed with wood powder and charcoal show higher degree as well. The highest grinding degree is Maekchil and Goksu but the lowest one is the sample of the rooftile powder mixture.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.369-375
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• 2022

Due to the so-called COVID-19 pandemic, railway service management has also faced an unprecedented situation over the past. This study conducted a survey of customers using high-speed railways during the COVID-19 pandemic to explore the impact of infectious diseases on the railway service customer experience. As a result, customer satisfaction and loyalty increase as customers are more aware of the quarantine-related services provided by railway operators. The moderating role of customer's COVID-19 risk perception was examined as well because there are individual differences in the level of thinking dangerously about Covid-19. As a result, the perceived level of the service's quarantine-related services has a significant impact on customer satisfaction when the customer's risk perception of Covid-19 is at an appropriate level, but its impact is relatively weak when the customer's risk perception is significantly high. Eventually, only the complete extinction of COVID-19 risk will bring a complete recovery to the service industry. Nevertheless, during the epidemic period, it was confirmed that the main service characteristics are that the service operator thoroughly conducts quarantine activities and faithfully communicates with customers.

• Journal of Animal Science and Technology
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• v.55 no.5
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• pp.359-365
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• 2013

Estimate breeding value can be used as single trait animal model was developed directly using the Fortran language program. The program is based on data computed by using the indirect method repeatedly. The program develops a common algorithm and imprves efficiency. Algorithm efficiency was compared between the two programs. Estimated using the solution is easy to farm and brand the service, pedigree data base was associated with the development of an improved system. The existing program that uses the single trait animal model and the comparative analysis of efficiency is weak because the estimation of the solution and the conventional algorithm programmed through regular formulation involve many repetition; therefore, the newly developed algorithm was conducted to improve speed by reducing the repetition. Single trait animal model was used to analyze Gauss-Seidel iteration method, and the aforesaid two algorithms were compared thorough the mixed model equation which is used the most commonly in estimating the current breeding value by applying the procedures such as the preparation of information necessary for modelling, removal of duplicative data, verifying the parent information of based population in the pedigree data, and assigning sequential numbers, etc. The existing conventional algorithm is the method for reading and recording the data by utilizing the successive repetitive sentences, while new algorithm is the method for directly generating the left hand side for estimation based on effect. Two programs were developed to ensure the accurate evaluation. BLUPF90 and MTDFREML were compared using the estimated solution. In relation to the pearson and spearman correlation, the estimated breeding value correlation coefficients were highest among all traits over 99.5%. Depending on the breeding value of the high correlation in Model I and Model II, accurate evaluation can be found. The number of iteration to convergence was 2,568 in Model I and 1,038 in Model II. The speed of solving was 256.008 seconds in Model I and 235.729 seconds in Model II. Model II had a speed of approximately 10% more than Model I. Therefore, it is considered to be much more effective to analyze large data through the improved algorithm than the existing method. If the corresponding program is systemized and utilized for the consulting of farm and industrial services, it would make contribution to the early selection of individual, shorten the generation, and cultivation of superior groups, and help develop the Hanwoo industry further through the improvement of breeding value based enhancement, ultimately paving the way for the country to evolve into an advanced livestock country.