KJC Korea
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In modern society, security-enhanced access control systems are an important factor. In this paper real-time smart access control system using a face recognition camera and OTAC(One Time Access Code) is proposed. This system especially focuses on the response speed of the embedded board to implement a delay-free system. Most access control systems on the market uses RFID to authenticate users. RFID has the advantage of fast authentication time and high usability. However, system’s weak points arise because others can steal and manipulate them. There are biometric recognition methods as supplant method, such as facial recognition, vein matching, iris recognition and fingerprint recognition are used as technical methods. The method proposed in this paper uses facial recognition technology and OTAC authentication. This is implemented on the embedded board by linking the depth information camera and the user DB server which is built on cloud environment. The embedded system was designed using Python, C++, C and PHP on Raspberry Pi 3 Model B+, Ubuntu 18.04 LTS and Arduino Due. Then communicated with each other using Wi-Fi and Serial Communication. In addition, the driving speed, one of the important specs, was 300 ms, which resulted in conformity with the designed specification. This system’s prototype was manufactured to prove the practicality and efficiency of the system.

E-commerce product recommendation uses various recommendation techniques. The recommendation techniques that are generally applied include the collaborative filtering technique, the user based collaborative filtering, and the item based collaborative filtering technique, and utilizes recommended techniques based on artificial intelligence technologies such as Recurrent Netural Network (RNN) and Long Short Term Memory (LSTM). The recommendation data generated through these recommendation techniques are stored in a database and are recommended in the form of static data by user actions (search, order, etc.). However, the recommendation through the static recommendation product list is limited in improving the purchasing power of the user. Providing a variety of recommended products and real-time properties, it is possible to further improve purchasing power if it is possible to dynamically construct a recommended product list. Therefore, this paper proposes an architecture and procedure for providing dynamic recommendations. The proposed dynamic recommendation architecture constructs a dynamic recommendation product by applying a static recommendation product based on Elasticsearch. In the experiment, accuracy was compared and analyzed by applying the same transaction data to existing recommendation techniques, and it was confirmed that the accuracy of the dynamic recommendation technique proposed in this paper is improved compared to the existing recommendation techniques.

In designing the branch line coupler, it is very important to set the impedance of each line because the amount of signal coupling at the output port is determined by the impedance of each line constituting the branch line. Since the coupling coefficient between the input and output ports is determined by the impedance condition of the line in the multi-stage branch line structure, the impedance of each line to obtain the desired coupling coefficient can be obtained by applying even-odd mode circuit analysis. In this paper, the multi-stage microstrip branch line structure is constructed and a hybrid coupling structure is used to distribute the half-power type of circuit lines connected to each port for signal transmission. We also obtained the broadband characteristics by optimizing the width and length of the line impedance to reduce the phase error within the operating range. We also analyzed the influence of the output signal amplitude and phase error on the beam pattern and beam steering direction obtained from the wide band design results of the five-stage branch line coupler. The fabricated hybrid branch line coupler has the operating frequency band of 2.15 GHz to 3.4 GHz, with a relative bandwidth of about 47%. In the band, the transmission characteristic and phase difference between output ports are less than 3.3 ± 0.5 dB and 90±1°. It shows good insertion loss, a half power and wide band characteristics.

The world's first 5G mobile service for general subscribers was commercialized in Korea in 2019, and will be commercialized worldwide-scale after this year. As a core infrastructure for the hyper-connected society in the era of the 4th industrial revolution, 5G technology requires more than 1000 times faster transmission speed than 4G LTE. In order to satisfy these requirements, mmWave technology, carrier aggregation technology, and MIMO (Multi Input Multi Output) antenna technology should be applied. The products that 5G technology required above, will be implemented are portable mobile devices such as smart-phones or smart-watches. In case of a smart-phone to which 5G is applied, 5G broadband multi-antenna must be additionally mounted in addition to the existing 2G/3G/4G cellular band antenna for high-speed multimedia support. The 5G frequency band must be additionally implemented in the existing antenna space of a smartphone. So, the antenna integration of 5G smaart-phone increases the coupling between multiple antennas and degrades antenna radiation performance. Therefore, antennas with 5G additional frequency band must be built in the same mounting space, so that antenna density must be increased. In addition, such an increase in the degree of antenna integration increases the coupling between multiple antennas, thereby deteriorating the antenna radiation performance. Therefore, various researches are continuously studied to improve the integration and the radiation performance of the multiple antenna simultaneously. In this paper, it is studied that anisotropic magneto-dielectric materials are effective in improving the coupling reduction between multiple antennas. It is proposed a method that can be applied to 5G MIMO antenna to satisfy the performance requirements.

Artificial Intelligence (AI) has become a hot topic since 2016 when Lee Se-dol and AlphaGo became a big hit. However, AlphaGo's computational results were made through the hand of a substitute driver in the game. It predicted that if there was hardware that matched advanced software, viewers would be more immersed in the Go game and that AlphaGo and Lee Se-dol would be clearly visible as AI and human. Therefore, in this paper, we want to design the combination between software and hardware using vision system and Robot for user immersion and real-time interactive communication with AI. In particular, unlike previous experiments in which only one robot was previously treated as a single robot and conducted only in a limited area, it induces higher user interaction through parallel processing in two. The implementation of the vision system took place in the Python environment of Zet Brains, and two robots are used. In fact, when a user starts a concave egg on a board of go, the starting point of the concave AI is calculated through the vision system, and the launch of the board is carried out through the robot. In conclusion, the proposed AI robotic omok platform based on multi-robot cooperative system proves its effectiveness and will be available in areas such as education for children with developmental disabilities.

Recently, studies on artificial intelligence has been actively conducted, and scholars and researchers are constantly trying to create artificial intelligence beyond humans. Machine learning uses mathematics' logical algorithms to learn, analyze and predict various data. It assists decision making based on this analysis. The goal is not to directly write algorithms optimized for software or programs, but to create execution capabilities by letting IT devices or electronic devices themselves learn using large-scale big data and learning algorithms. Linear regression is a regression analysis method that models the linear correlation between one or more independent variables(x) and a dependent variable(y). Generally, a linear regression model is established using a least squares method. Multiple linear regression analysis targets regression models with two or more independent variables. Simple regression analysis can bring bias by estimating with only one independent variable. A baseball player's pitching ability depends on his speed, ball and concentration. In particular, among pitchers' stats, WHIP, H/9(Hits Runs Allowed Per 9 Innings Pitched) and K/9(Strikeout Per 9 Innings Pitched) are important measures of pitching. In this paper, the ERA(Earned Run Average) is predicted using the pitcher's WHIP, H/9 and K/9 as training data. We can predict whether a specific pitcher will be nominated for a professional baseball player or not.

This paper seeks to recognize the importance of cyber-security in national security, especially in the Internet environment, in the reality of building a smart ecosystem globally. Digital transformation and 5G innovation are happening more rapidly after the Corona 19 incident. The dailyization of information and communication and the expanded use of cyberspace can be felt in our real life. Globalization of global villages, the realization of smart cities and e-government in Korea is happening realistically. The use of information and communication in the essential daily life of everyone, such as finance, medical care, and education, is taken for granted, and the problem of cyber space is not a problem of only a specific group, but a problem that is directly related to all citizens. In order to protect the nation's important facilities and systems from packet-type cyber terrorism and attacks, we will look at monitoring and regulation of Internet circuits in terms of national security. The purpose of this study is to grasp the technical characteristics of communication restriction measures (aka' packet interception') on Internet circuits and to suggest the direction of investigation on interception of packets through comparative law review. Review and revise the Constitutional Inconsistency Case of the Constitutional Court regarding whether the communication restriction measures (packet interception) through the Internet line prescribed by the Communication Secret Protection Act contradicts the principle of excess provision and proportion of Article 37 (2) of the Constitution. Through the provisions of the secret law, we will look into the problems and improvement measures of the current cyber security system, especially related to national security.

Modern information and communication technologies, including internet of things, artificial intelligence, cyber physical system, big data, cloud computing, robotics and mobile sensor network, are believed to enable the fourth industrial revolution, Industry 4.0. Inherently, industrial revolution indicates a dramatical increase in productivity of production systems. In this context, smart factory has emerged as an important topic for both researchers and practitioners. Smart factory is manufacturing facility equipped with modern information and communication technologies, and its objective is to utilize the resources in manufacturing shop floors more efficiently so that competitiveness of manufacturing company is maximized. It is straightforward that various software and hardware solutions are integral parts of smart factory. However, human operators also play essential roles in smart factory environment. In other words, smart factory is also a sort of highly complex socio-technical system where human operators and modern technologies interact with each other, and it might raise a wide range of legal issues in future. The objective of this paper is to examine the legal environment of smart factory and discuss the potential legal issues. Especially, we focus on legal issues related to government support system and occupational safety and health. Consequently, we expect that this paper will provide an meaningful insight into the legal aspects of smart factory.

The existing donation system did not allow donors to know the donations used by donor organizations. As a solution, the method of storing donation details of donation organizations on the blockchain was introduced. This has the advantage of being unable to hide or modify the details, but there is no way to verify them if the donor organization intentionally manipulates them and stores them in the block chain. In this paper, we propose a reliable donation service using Ethereum Blockchain. Unlike the existing donation system, it helps to make reliable donations by storing immutable transaction details in the blockchain. Sellers selling goods, donors making donations, and social organizations using donations join one service to store all transactions in the blockchain. The transaction details associated with the donation are disclosed to all users and transaction ID is provided so that everyone can verify the transaction. The proposed service can prevent social organizations from the use of donations for their own interests because they have to purchase the goods using donations through the proposed service and provide them to the recipient. As a result, the proposed service can provide more transparency to donors and we can expect more donations from donors. We use the Ethereum platform and node.js server to implement the system.

This study examined if gender has any impact on the use of smart media and SNS fatigue of university students while analyzing its effects in moderating the relationship between SNS fatigue and academic procrastination behaviors and learning flow. Data were collected from 267 students from 4-year university located in Seoul and Pusan(male 60.3%), and analyzed by means of t-test and hierarchical regression analyses. The results of the study are following: First, female students spent more time in using smart media than did male students; Second, the frequency of using smart media per day was significantly higher for male students compared to female students. Third, female students were found out to feel more SNS fatigue than male students; Fourth, female students also showed higher score in the variable of academic procrastination behaviors than did male students; Fifth, the moderating effect of gender on academic procrastination behaviors via SNS fatigue was statistically significant, meaning that female students who felt high degree of SNS fatigue were more vulnerable to academic procrastination behaviors than the case of male students. Lastly, however, the moderating effect was not found out in the relationship between SNS fatigue and learning flow. In summary, this study showed the plausibility of female students spending more time on smart media, feeling more SNS fatigue, and finally procrastinating academic work more than did male students. Therefore, this study suggested that gender should be considered at first when higher education institutions plan to provide intervention programs for their students to prevent them from the overuse of smart media and suffering from SNS fatigue.

This study aims to designed and implemented a prescription support system to search and suggest prescriptions to treat symptoms of patients based on Korean medicine ontology. The Korean medicine ontology have constructed to represent the information on textbooks used in Korean medicine colleges using Web Ontology Language (OWL). However, OWL is stored and queried in the form of a graph database. Because it is not flexible to link with other systems such as electronic charts, we convert the graph data of the OWL database to the table data of the relational database. We also designed the database tables for the prescription support system based on the e-government framework. The prescription support system in this paper constructed to provide the functions such as prescription search, patient management, and treatment management to facilitate the practical clinical uses. The user interface was designed for the convenience of inputting symptoms, and functions of the prescription management such as sort, comparison, addition and subtraction, and agreed prescription were implemented. In the future, we will study to increase the utilization of the prescription support system in connection with electronic charts in hospitals and mobile applications for the personal health care. In addition, the prescription recommendation function will be enhanced by using the classification and synonyms of symptom terms.

In this study, with the development of the Indian e-commerce market, the online market is expanding even more than the offline market. We studied how the e-commerce environment changes in such an expanding environment. Also, India currently has the second largest population in the world, with overseas e-commerce companies penetrating the Indian market a lot. Although India's infrastructure environment is improving as many foreign companies enter the Indian market, creating a better e-commerce market environment, as the e-commerce market progresses, the Indian government has begun to tighten regulations on overseas e-commerce companies. To that end, we studied how foreign e-commerce companies should enter the Indian market. And we studied and investigated how this payment method is used and what the problem is when we mainly use the Cash on Delivery (COD) payment method, which is different from Korea's e-commerce platform and e-commerce settlement method. This study is to study the features, regulations and platforms of e-commerce in India, and also to suggest strategies for the development of the e-commerce market in India.

The purpose of this study is to find evidence to promote interaction in cooperative learning. To this end, the contents of the interaction rules voluntarily suggested by learners were examined, and the learners' perceptions of the effectiveness of the interaction rules were analyzed. The data for this study included group activity rules voluntarily set by learners in cooperative learning classes conducted by the researcher over an eight semester period beginning in 2016 and ending in 2019. The learners set five categories of rules for learning effectiveness in cooperative learning: First, rules for active participation, second, rules for ensuring fairness, third, rules for respecting members, fourth, rules for establishing intimate relationships with members, and finally penalties for breaking the rules. The results showed that the rules had a positive effect in connection with the objectives set initially. It was reported that the rules gave formality to group activities to encourage active participation, and helped maintain fairness due to their increased accountability for the implementation of the rules. Moreover, the learners responded that by applying the rules of consideration and respect for the group members, they were able to establish a closer relationship with their group members. The negative effects of the use of interaction rules, however, need to be addressed in order to improve compliance by learners and allow for appropriate intervention by the instructor. This study is meaningful in that it reveals the basis for effective cooperative learning strategies from the learners' point of view.