• Journal of Digital Convergence
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• v.17 no.1
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• pp.239-247
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• 2019

An accurate prediction of emotion is a very important issue for the sake of patient-centered medical device development and emotion-related psychology fields. Although there have been many studies on emotion prediction, no studies have applied the heart rate variability and neuro-fuzzy approach to emotion prediction. We propose ANFEP(Adaptive Neuro Fuzzy System for Emotion Prediction) HRV. The ANFEP bases its core functions on an ANFIS(Adaptive Neuro-Fuzzy Inference System) which integrates neural networks with fuzzy systems as a vehicle for training predictive models. To prove the proposed model, 50 participants were invited to join the experiment and Heart rate variability was obtained and used to input the ANFEP model. The ANFEP model with STDRR and RMSSD as inputs and two membership functions per input variable showed the best results. The result out of applying the ANFEP to the HRV metrics proved to be significantly robust when compared with benchmarking methods like linear regression, support vector regression, neural network, and random forest. The results show that reliable prediction of emotion is possible with less input and it is necessary to develop a more accurate and reliable emotion recognition system.

• Journal of Powder Materials
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• v.30 no.4
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• pp.324-331
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• 2023

Lithium (Li) is a key resource driving the rapid growth of the electric vehicle industry globally, with demand and prices continually on the rise. To address the limited reserves of major lithium sources such as rock and brine, research is underway on seawater Li extraction using electrodialysis and Li-ion selective membranes. Lithium lanthanum titanate (LLTO), an oxide solid electrolyte for all-solid-state batteries, is a promising Li-ion selective membrane. An important factor in enhancing its performance is employing the powder synthesis process. In this study, the LLTO powder is prepared using two synthesis methods: sol-gel reaction (SGR) and solid-state reaction (SSR). Additionally, the powder size and uniformity are compared, which are indices related to membrane performance. X-ray diffraction and scanning electron microscopy are employed for determining characterization, with crystallite size analysis through the full width at half maximum parameter for the powders prepared using the two synthetic methods. The findings reveal that the powder SGR-synthesized powder exhibits smaller and more uniform characteristics (0.68 times smaller crystal size) than its SSR counterpart. This discovery lays the groundwork for optimizing the powder manufacturing process of LLTO membranes, making them more suitable for various applications, including manufacturing high-performance membranes or mass production of membranes.

• Journal of Aerospace System Engineering
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• v.16 no.1
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• pp.56-69
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• 2022

Various advanced countries are accelerating the competition in the development of hypersonic weapons. North Korea is on the verge of building a new submarine equipped with a submarine-launched ballistic missile (SLBM). A series of new guided missiles tests have continued due to political competition between the U.S. and China. The Republic of Korea is planning to boost its military capabilities, which involves the development of nuclear-powered submarines, light aircraft carriers, and new guided missiles. The northeast Asian region continues to be tense amid military rivalry between the Republic of Korea, North Korea, the United States, China, Russia, and Japan. Accordingly, these countries' competition to develop weapons is also at the world's highest level. In this paper, we examine the functioning of a hypersonic weapons system conduct a technical analysis of its components. In addition, we analyze the direction of military development that the Korean military wants to pursue through the recently announced mid-term defense plan. We conclude by highlighting the technical limitations and implementation strategies to overcome the development of hypersonic weapons.

• Journal of Advanced Information Technology and Convergence
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• v.9 no.1
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• pp.115-125
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• 2019

In this paper, the image is received from the camera and the lane is sensed. There are various ways to detect lanes. Generally, the method of detecting edges uses a lot of the Sobel edge detection and the Canny edge detection. The minimum use of multiplication and division is used when designing for the hardware configuration. The images are tested using a black box image mounted on the vehicle. Because the top of the image of the used the black box is mostly background, the calculation process is excluded. Also, to speed up, YCbCr is calculated from the image and only the data for the desired color, white and yellow lane, is obtained to detect the lane. The median filter is used to remove noise from images. Intermediate filters excel at noise rejection, but they generally take a long time to compare all values. In this paper, by using addition, the time can be shortened by obtaining and using the result value of the median filter. In case of the Sobel edge detection, the speed is faster and noise sensitive compared to the Canny edge detection. These shortcomings are constructed using complementary algorithms. It also organizes and processes data into parallel processing pipelines. To reduce the size of memory, the system does not use memory to store all data at each step, but stores it using four line buffers. Three line buffers perform mask operations, and one line buffer stores new data at the same time as the operation. Through this work, memory can use six times faster the processing speed and about 33% greater quantity than other methods presented in this paper. The target operating frequency is designed so that the system operates at 50MHz. It is possible to use 2157fps for the images of 640by360 size based on the target operating frequency, 540fps for the HD images and 240fps for the Full HD images, which can be used for most images with 30fps as well as 60fps for the images with 60fps. The maximum operating frequency can be used for larger amounts of the frame processing.

• Electrical & Electronic Materials
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• v.12 no.7
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• pp.7-11
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• 1999

Fully sealed field emission display in size of 4.5 inch has been fabricated using single-wall carbon nanotubes-organic vehicle com-posite. The fabricated display were fully scalable at low temperature below 415$^{\circ}C$ and CNTs were vertically aligned using paste squeeze and surface rubbing techniques. The turn-on fields of 1V/${\mu}{\textrm}{m}$ and field emis-sion current of 1.5mA at 3V/${\mu}{\textrm}{m}$ (J=90${\mu}{\textrm}{m}$/$\textrm{cm}^2$)were observed. Brightness of 1800cd/$m^2$ at 3.7V/${\mu}{\textrm}{m}$ was observed on the entire area of 4.5-inch panel from the green phosphor-ITO glass. The fluctuation of the current was found to be about 7% over a 4.5-inch cath-ode area. This reliable result enables us to produce large area full-color flat panel dis-play in the near future. Carbon nanotubes (CNTs) have attracted much attention because of their unique elec-trical properties and their potential applica-tions [1, 2]. Large aspect ratio of CNTs together with high chemical stability. ther-mal conductivity, and high mechanical strength are advantageous for applications to the field emitter [3]. Several results have been reported on the field emissions from multi-walled nanotubes (MWNTs) and single-walled nanotubes (SWNTs) grown from arc discharge [4, 5]. De Heer et al. have reported the field emission from nan-otubes aligned by the suspension-filtering method. This approach is too difficult to be fully adopted in integration process. Recently, there have been efforts to make applications to field emission devices using nanotubes. Saito et al. demonstrated a car-bon nanotube-based lamp, which was oper-ated at high voltage (10KV) [8]. Aproto-type diode structure was tested by the size of 100mm $\times$ 10mm in vacuum chamber [9]. the difficulties arise from the arrangement of vertically aligned nanotubes after the growth. Recently vertically aligned carbon nanotubes have been synthesized using plasma-enhanced chemical vapor deposition(CVD) [6, 7]. Yet, control of a large area synthesis is still not easily accessible with such approaches. Here we report integra-tion processes of fully sealed 4.5-inch CNT-field emission displays (FEDs). Low turn-on voltage with high brightness, and stabili-ty clearly demonstrate the potential applica-bility of carbon nanotubes to full color dis-plays in near future. For flat panel display in a large area, car-bon nanotubes-based field emitters were fabricated by using nanotubes-organic vehi-cles. The purified SWNTs, which were syn-thesized by dc arc discharge, were dispersed in iso propyl alcohol, and then mixed with on organic binder. The paste of well-dis-persed carbon nanotubes was squeezed onto the metal-patterned sodalime glass throuhg the metal mesh of 20${\mu}{\textrm}{m}$ in size and subse-quently heat-treated in order to remove the organic binder. The insulating spacers in thickness of 200${\mu}{\textrm}{m}$ are inserted between the lower and upper glasses. The Y\ulcornerO\ulcornerS:Eu, ZnS:Cu, Al, and ZnS:Ag, Cl, phosphors are electrically deposited on the upper glass for red, green, and blue colors, respectively. The typical sizes of each phosphor are 2~3 micron. The assembled structure was sealed in an atmosphere of highly purified Ar gas by means of a glass frit. The display plate was evacuated down to the pressure level of 1$\times$10\ulcorner Torr. Three non-evaporable getters of Ti-Zr-V-Fe were activated during the final heat-exhausting procedure. Finally, the active area of 4.5-inch panel with fully sealed carbon nanotubes was pro-duced. Emission currents were character-ized by the DC-mode and pulse-modulating mode at the voltage up to 800 volts. The brightness of field emission was measured by the Luminance calorimeter (BM-7, Topcon).

• Journal of Appropriate Technology
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• v.7 no.2
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• pp.127-135
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• 2021

To respond to the threat of global warming, countries around the world are promoting the spread of renewable energy and reduction of carbon emissions. In accordance with the United Nation's Sustainable Development Goal to combat climate change and its impacts, global automakers are pushing for a full transition to electric vehicles within the next 10 years. Electric vehicles can be a useful means for reducing carbon emissions, but in order to reduce carbon generated in the stage of producing electricity for charging, a power generation system using eco-friendly renewable energy is required. In this study, we propose a smart electric mobility operating system integrated with off-grid solar power plants established in Tanzania, Africa. By applying smart monitoring and communication functions based on Arduino-based computing devices, information such as remaining battery capacity, battery status, location, speed, altitude, and road conditions of an electric vehicle or electric motorcycle is monitored. In addition, we present a scenario that communicates with the surrounding independent solar power plant infrastructure to predict the drivable distance and optimize the charging schedule and route to the destination. The feasibility of the proposed system was verified through test runs of electric motorcycles. In considering local environmental characteristics in Tanzania for the operation of the electric mobility system, factors such as eco-friendliness, economic feasibility, ease of operation, and compatibility should be weighed. The smart electric mobility operating system proposed in this study can be an important basis for implementing the SDGs' climate change response.

• The Journal of the Korea Contents Association
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• v.17 no.12
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• pp.461-472
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• 2017

The purpose of this study is to analyze the current status and condition of children's playgrounds in K which parents recognize as in Gyeonggi-do and provide basic data for the qualitative environment for daily outdoor play of young Children. To do so, a survey of 269 parents living in Gyeonggi-do was conducted and reconstructed based on the advanced research related to outdoor play. Also it was evaluated and revised after consultation with 3 children education specialists. The repossessed questionaries were frequency-analyzed with SPSS 20.0 program. The result of the analysis on outdoor playgrounds is in the following. First of all, it was analyzed that parents required 1 or 2 hours for their children to play outdoors in a type of "forest playgrounds." Moreover, they said that it was really important for the children to feel "interesting and funny" during the outdoor play, and they recognized that the play would be helpful for the children's socialization. However, they felt that a risk factor of the outdoor play was "a vehicle risk in streets." Secondly, the study suggested that there were outdoor playgrounds around parents' houses, and a type of the outdoor play was "a playground installed in the apartment complex." Furthermore, most of the parents weren't satisfied with the outdoor play because the apartment neglected the management of the playgrounds, and there were no playing facilities that were good enough to derive children's curiosity and adventurous spirit. The result also showed that most of the children played outdoors with "their mothers," and they participated in indoor activities, especially playing a game or watching TV rather than outdoor activities after attending a children educational institute. Lastly, when it comes to areas of outdoor play to be improved, it was necessary to "expand playgrounds that children can use for each season," build "safe playgrounds" for a type of the outdoor play," provide "playing spaces" for a spatial type, and "control vehicles around the playgrounds and deal with dangerous things" to prevent safety accidents. The result can expand the understanding of outdoor play for Young Children and offer discussions about the relevant organizations and studies.

• The Korean Journal of Air & Space Law and Policy
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• v.33 no.1
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• pp.175-204
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• 2018

Recently, the aviation leisure business has been legislated, and related industries have become active base with increasing the light sports aircraft within the legislation system. However, in the light sports aircraft safety problem, it is often mentioned that the flight is in violation of the regulations, the lack of safety consciousness of the operator and lack of ability, and the personal operators have a risk of accident of light aircraft such as insufficient safety management and poor maintenance. At present, the maintenance of light sports aircraft is carried out by the A & P mechanic in accordance with the relevant laws and regulations, but it is difficult to say that it is equipped with qualification and expertise. It is not a legal issue to undertake light sports aircraft maintenance work on the regulation system. However, the problem of reliability and appropriateness is constantly being raised because airplanes, light sports aircraft, and ultra-light vehicle are classified and serviced in a legal method. Although legal and institutional frameworks for light sports aircraft are separated, much of it is stipulated in the aviation law provisions. Light sports aircraft maintenance work also follows the current aircraft maintenance system. In the United States, Europe, and Australia where General Aviation developed, legal and institutional devices related to maintenance of light aircraft were introduced, and specialized maintenance tasks are covered in the light aircraft mechanics system. As a result of analysis of domestic and foreign laws and regulations, it is necessary to introduce the qualification system for maintenance of light aircraft. In advanced aviation countries such as the United States, Europe, and Australia, a light sports aircraft repairman system is installed to perform safety management. This is to cope with changes in the operating environment of the new light sports aircraft. This study does not suggest the need for a light aircraft repairman system. From the viewpoint of the legal system, the examination of the relevant laws and regulations revealed that the supplementary part of the system is necessary. It is also require that the necessity of introduction is raised in comparison with overseas cases. Based on these results, it is necessary to introduce the system into the light aircraft repairman system, and suggestions for how to improve it are suggested.

• The Korean Journal of Air & Space Law and Policy
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• v.28 no.2
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• pp.295-347
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• 2013

Korea launched the science satellite by the first launch vehicle Naro-ho(KSLV-1) at the Naro Space Center located at Oinarodo, Cohenggun Jellanamdo in August, 2009 and October, 2010. However, the first and second launch failed. At last, on January 30, 2013 the third launch of the launch vehicle Naro-ho has successfully launched and the Naro science satellite penetrated into the space orbit. Owing to the succeed of the launch of Naro-ho, Korea joined the space club by the eleventh turn following the United States, Russia, Japan and China. The United Nations adopted the Outer Space Treaty of 1967, the Rescue Agreement of 1968, the Liability Convention of 1972, the Regislation Convention of 1976, and Moon Agreement of 1979. Korea ratified the above space-related treaties except the Moon Agreement. Such space-related treaties regulate the international liability for the space activity by the launching state of the space object. Especially the Outer Space Treaty regulates the principle concerning the state's liability for the space activity. Each State Party to the Treaty that launches or procures the launching of an object into outer space is internationally liable for damage to another State Party or to its natural or judicial persons by such object or its component parts on the earth, in air space or in outer space. Under the Liability Convention, a launching state shall be absolutely liable to pay compensation for damage caused by its space object on the surface of the earth or to aircraft in flight. The major nations of the world made national legislations to observe the above space-related treaties, and to promote the space development, and to regulate the space activity. In Korea, the United States, Russia and Japan, the national space-related legislation regulates the government's liability of the launching state of the space object. The national space-related legislations of the major nations are as follows : the Outer Space Development Promotion Act and Outer Space Damage Compensation Act of Korea, the National Aeronautic and Space Act and Commercial Space Launch Act of the United States, the Law on Space Activity of Russia, and the Law concerning Japan Aerospace Exploration Agency and Space Basic Act of Japan. In order to implement the government's liability of the launching state of space object under space-related treaties and national legislations, and to establish the standing as a strong space nation, Korea shall improve the space-related policy, laws and system as follows : Firstly, the legal system relating to the space development and the space activity shall be maintained. For this matter, the legal arrangement and maintenance shall be made to implement the government's policy and regulation relating to the space development and space activity. Also the legal system shall be maintained in accordance with the elements for consideration when enacting the national legislation relevant to the peaceful exploration and use of outer space adopted by UN COPUOS. Secondly, the liability system for the space damage shall be improved. For this matter, the articles relating to the liability for the damage and the right of claiming compensation for the expense already paid for the damage in case of the joint launch and consigned launch shall be regulated newly. Thirdly, the preservation policy for the space environment shall be established. For this matter, the consideration and preservation policy of the environment in the space development and use shall be established. Also the rule to mitigate the space debris shall be adopted. Fourthly, the international cooperation relating to the space activity shall be promoted. For this matter, the international cooperation obligation of the nation in the exploration and use of outer space shall be observed. Also through the international space-related cooperation, Korea shall secure the capacity of the space development and enter into the space advanced nation.