Korean | English

pISSN : 1598-849X / eISSN : 2383-9945

2020 KCI Impact Factor : 0.4
Home > Explore Content > All Issues > Article List

2021, Vol.26, No.3

  • 1.

    Realtime Media Streaming Technique Based on Adaptive Weight in Hybrid CDN/P2P Architecture

    Junpyo Lee | 2021, 26(3) | pp.1~7 | number of Cited : 0
    Abstract PDF
    In this paper, optimized media data retrieval and transmission based on the Hybrid CDN/P2P architecture and selective storage through user's prediction of requestability enable seamless data transfer to users and reduction of unnecessary traffic. We also propose a new media management method to minimize the possibility of transmission delay and packet loss so that media can be utilized in real time. To this end, we construct each media into logical segments, continuously compute weights for each segment, and determine whether to store segment data based on the calculated weights. We also designate scattered computing nodes on the network as local groups by distance and ensure that storage space is efficiently shared and utilized within those groups. Experiments conducted to verify the efficiency of the proposed technique have shown that the proposed method yields a relatively good performance evaluation compared to the existing methods, which can enable both initial latency reduction and seamless transmission.
  • 2.

    A Study of Collaborative and Distributed Multi-agent Path-planning using Reinforcement Learning

    Kim, Min-suk | 2021, 26(3) | pp.9~17 | number of Cited : 0
    Abstract PDF
    In this paper, an autonomous multi-agent path planning using reinforcement learning for monitoring of infrastructures and resources in a computationally distributed system was proposed. Reinforcement-learning-based multi-agent exploratory system in a distributed node enable to evaluate a cumulative reward every action and to provide the optimized knowledge for next available action repeatedly by learning process according to a learning policy. Here, the proposed methods were presented by (a) approach of dynamics-based motion constraints multi-agent path-planning to reduce smaller agent steps toward the given destination(goal), where these agents are able to geographically explore on the environment with initial random-trials versus optimal-trials, (b) approach using agent sub-goal selection to provide more efficient agent exploration(path-planning) to reach the final destination(goal), and (c) approach of reinforcement learning schemes by using the proposed autonomous and asynchronous triggering of agent exploratory phases.
  • 3.

    Automatic Anatomical Classification Model of Esophagogastroduodenoscopy Images Using Deep Convolutional Neural Networks for Guiding Endoscopic Photodocumentation

    Jung Whan Park | Kim, yoon | Kim, WooJin and 1other persons | 2021, 26(3) | pp.19~28 | number of Cited : 0
    Abstract PDF
    Esophagogastroduodenoscopy is a method commonly used for early diagnosis of upper gastrointestinal lesions. However, 10-20 percent of the gastric lesions are reported to be missed, due to human error. And countries including the US, the UK, and Japan, the World Endoscopy Organization (WEO) suggested guidelines about essential gastrointestinal parts to take pictures of so that all gastric lesions are observed. In this paper, we propose deep learning techniques for classification of anatomical sites, aiming for the system that informs practitioners whether they successfully did the gastroscopy without blind spots. The proposed model uses pre-processing modules and data augmentation techniques suitable for gastroscopy images. Not only does the experiment result with a maximum F1 score of 99.6%, but it also shows a error rate of less than 4% based on the actual data. Given the performance results, we found the model to be explainable with the potential to be utilized in the clinical area.
  • 4.

    Development of Artificial Intelligence-based Legal Counseling Chatbot System

    park koo rack | 2021, 26(3) | pp.29~34 | number of Cited : 0
    Abstract PDF
    With the advent of the 4th industrial revolution era, IT technology is creating new services that have not existed by converging with various existing industries and fields. In particular, in the field of artificial intelligence, chatbots and the latest technologies have developed dramatically with the development of natural language processing technology, and various business processes are processed through chatbots. This study is a study on a system that provides a close answer to the question the user wants to find by creating a structural form for legal inquiries through Slot Filling-based chatbot technology, and inputting a predetermined type of question. Using the proposal system, it is possible to construct question-and-answer data in a more structured form of legal information, which is unstructured data in text form. In addition, by managing the accumulated Q&A data through a big data storage system such as Apache Hive and recycling the data for learning, the reliability of the response can be expected to continuously improve.
  • 5.

    Deep learning based Person Re-identification with RGB-D sensors

    Min-Kim | PARK DONGHYUN | 2021, 26(3) | pp.35~42 | number of Cited : 0
    Abstract PDF
    In this paper, we propose a deep learning-based person re-identification method using a three-dimensional RGB-Depth Xtion2 camera considering joint coordinates and dynamic features(velocity, acceleration). The main idea of the proposed identification methodology is to easily extract gait data such as joint coordinates, dynamic features with an RGB-D camera and automatically identify gait patterns through a self-designed one-dimensional convolutional neural network classifier(1D-ConvNet). The accuracy was measured based on the F1 Score, and the influence was measured by comparing the accuracy with the classifier model (JC) that did not consider dynamic characteristics. As a result, our proposed classifier model in the case of considering the dynamic characteristics(JCSpeed) showed about 8% higher F1-Score than JC.
  • 6.

    A Design and Implementation of Fitness Application Based on Kinect Sensor

    Lee, Won Joo | 2021, 26(3) | pp.43~50 | number of Cited : 0
    Abstract PDF
    In this paper, we design and implement KITNESS, a windows application that feeds back the accuracy of fitness motions based on Kinect sensors. The feature of this application is to use Kinect's camera and joint recognition sensor to give feedback to the user to exercise in the correct fitness position. At this time, the distance between the user and the Kinect is measured using Kinect's IR Emitter and IR Depth Sensor, and the joint, which is the user's joint position, and the Skeleton data of each joint are measured. Using this data, a certain distance is calculated for each joint position and posture of the user, and the accuracy of the posture is determined. And it is implemented so that users can check their posture through Kinect's RGB camera. That is, if the user's posture is correct, the skeleton information is displayed as a green line, and if it is not correct, the inaccurate part is displayed as a red line to inform intuitively. Through this application, the user receives feedback on the accuracy of the exercise position, so he can exercise himself in the correct position. This application classifies the exercise area into three areas: neck, waist, and leg, and increases the recognition rate of Kinect by excluding positions that Kinect does not recognize due to overlapping joints in the position of each exercise area. And at the end of the application, the last exercise is shown as an image for 5 seconds to inspire a sense of accomplishment and to continuously exercise.
  • 7.

    Artificial Neural Network Method Based on Convolution to Efficiently Extract the DoF Embodied in Images

    Jong-Hyun Kim | 2021, 26(3) | pp.51~57 | number of Cited : 0
    Abstract PDF
    In this paper, we propose a method to find the DoF(Depth of field) that is blurred in an image by focusing and out-focusing the camera through a efficient convolutional neural network. Our approach uses the RGB channel-based cross-correlation filter to efficiently classify the DoF region from the image and build data for learning in the convolutional neural network. A data pair of the training data is established between the image and the DoF weighted map. Data used for learning uses DoF weight maps extracted by cross-correlation filters, and uses the result of applying the smoothing process to increase the convergence rate in the network learning stage. The DoF weighted image obtained as the test result stably finds the DoF region in the input image. As a result, the proposed method can be used in various places such as NPR(Non-photorealistic rendering) rendering and object detection by using the DoF area as the user's ROI(Region of interest).
  • 8.

    A Survey of Decentralized Finance(DeFi) based on Blockchain

    Junsang Kim | Seyong Kim | 2021, 26(3) | pp.59~67 | number of Cited : 0
    Abstract PDF
    Blockchain technology began in 2008 when an unidentified person named Satoshi Nakamoto proposed a cryptocurrency called Bitcoin. Satoshi Nakamoto had distrust of the existing financial system and wanted to implement a financial system that is robust against hacking or mannipulation without a middleman such as a bank through blockchain technology. Satoshi proposed a blockchain as a technology to prevent the creation of the bitcoin and forging of transactions, and through this, the functions of issuance, transaction, and verification of currency were implemented. Since then, Ethereum, a cryptocurrency that can implement the smart contract on the blockchain, has been developed, allowing financial products that require complex contracts such as deposits, loans, insurance, and derivatives to be brought into the area of cryptocurrency. In addition, it is expanding the possibility of substituting products provided by financial institutions through combination with real assets. These applications are defined as Decentralized Finance (DeFi). This paper was prepared to understand the overall technical understanding of DeFi and to introduce the services currently in operation. First, the technologies and ecosystems that implement the overall DeFi are explained, and then the representative DeFi services are categorized by feature and described.
  • 9.

    Analysis of Forwarding Schemes to Mitigate Data Broadcast Storm in Connected Vehicles over VNDN

    Daewon Hur | Huhnkuk Lim | 2021, 26(3) | pp.69~75 | number of Cited : 0
    Abstract PDF
    Limitation of the TCP/IP network technology included in the vehicle communication is due to the frequent mobility of the vehicle, the increase in intermittent connection requirements, and the constant presence of the possibility of vehicle hacking. VNDN technology enables the transfer of the name you are looking for using textual information without the need for vehicle identifiers like IP/ID. In addition, intermittent connectivity communication is possible rather than end-to-end connection communication. The data itself is the subject of communication based on name-based forwarding using two types of packets: Interest packet and Data packet. One of the issues to be solved for the realization of infotainment services under the VNDN environment is the traffic explosion caused by data broadcasting. In this paper, we analyze and compare the existing technologies to reduce the data broadcast storm. Through this, we derive and analyze the requirements for presenting the best data mitigation technique for solving the data explosion phenomenon in the VNDN environment. We expect this paper can be utilized as prior knowledge in researching improved forwarding techniques to resolve the data broadcast explosion in connected vehicles over NDN.
  • 10.

    A Study on the Collaborative Inventory Management of Big Data Supply Chain : Case of China's Beer Industry

    Jinhui Chen | Jin Chan Yong | 2021, 26(3) | pp.77~88 | number of Cited : 0
    Abstract PDF
    The development history of China's big data is relatively short, and it has only been ten years so far. Although the application level of big data in real life is not high, some achievements have been made in the supply chain. Various kinds of data will be generated in the actual operation of the supply chain. If these data can be effectively classified and used, the "bullwhip effect" of the operation of the supply chain can be also effectively improved. Thus this paper proposes the development of a supply chain collaborative inventory management model and application framework using big data. In this study, we analyzed the supply chain of beer industry, which is the most prominent consumption industry with "bullwhip effect", and further established a big data collaborative inventory management model for the supply chain of beer industry based on system dynamics. We used the Vensim software for simulation and sensitivity test and after appling our model, we found that the inventory fluctuations of the participants in the beer industry supply chain became significantly smaller, which verified the effectiveness of the model. Our study can be also applied to the possible problems of the large data supply chain collaborative inventory management model, and gives certain countermeasures and suggestions.
  • 11.

    A Study of the Operation Management Strategy on the National Critical Infrastructures : Transportation and Logistics Sector

    Sunghak Chung | 2021, 26(3) | pp.89~97 | number of Cited : 0
    Abstract PDF
    The objective of this study is to propose an operation management strategy for the connectivity which are the designated and managed in sector of the transportation and logistics on the national critical infrastructures. The industrial structure is becoming advanced. The national critical infrastructure managed by the shows forms of the cooperative connection and collaborative R&D. Also, in-depth and specific analysis for the disaster safety budget are implemented to consideration for the R&D life cycle. The government responsibility are expanded comprehensively. Needs are exchanging life styles by the economic and safety demands. At this trends, this study encourage facility maintenance and scientific management to the public service. Throughout the result of this study, national critical infrastructure are implementing for protection plan of the sustainable maintenance and management. And, we have to prepare and implement for the consideration of the characteristics through comprehensive guidelines. This study contributes to the disaster and safety management by proposed an operation strategy of the cooperative connection in the sector of transportation and logistic sector on the national critical infrastructure.
  • 12.

    Using Requirements Engineering to support Non-Functional Requirements Elicitation for DAQ System

    Kim Kyung sik | Seok-Won Lee | 2021, 26(3) | pp.99~109 | number of Cited : 0
    Abstract PDF
    In recent machine learning studies, in order to consider the quality and completeness of data, derivation of non-functional requirements for data has been proposed from the viewpoint of requirements engineering. In particular, requirements engineers have defined data requirements in machine learning. In this study, data requirements were derived at the data acquisition (DAQ) stage, where data is collected and stored before data preprocessing. Through this, it is possible to express the requirements of all data required in the existing DAQ system, the presence of tasks (functions) satisfying them, and the relationship between the requirements and functions. In addition, it is possible to elicit requirements and to define the relationship, so that a software design document can be produced, and a systematic approach and direction can be established in terms of software design and maintenance. This research using existing DAQ system cases, scenarios and use cases for requirements engineering approach are created, and data requirements for each case are extracted based on them, and the relationship between requirements, functions, and goals is illustrated through goal modeling. Through the research results, it was possible to extract the non-functional requirements of the system, especially the data requirements, from the DAQ system using requirements engineering.
  • 13.

    Optimal Solution Algorithm for Delivery Problem on Graphs

    Lee Kwang Eui | 2021, 26(3) | pp.111~117 | number of Cited : 0
    Abstract PDF
    The delivery problem on a graph is that of minimizing the object delivery time from one vertex to another vertex on a graph with  vertices using  various speed robot agents. In this paper, we propose two optimal solution algorithms for the delivery problem on a graph with time complexity of   and   . After preprocessing to obtain the shortest path for all pairs of the graph, our algorithm processed by obtaining the shortest delivery path in the order of the vertices with the least delivery time. Assuming that the graph reflects the terrain on which to solve the problem, our    algorithm actually has a time complexity of   as only one preprocessing is required for the various deployment of n robot agents.
  • 14.

    Modern Pentathlon’s Sports Spirit and A Study on Leader's Ethical Exploration

    Doryung Han | 2021, 26(3) | pp.119~126 | number of Cited : 0
    Abstract PDF
    The modern pentathlon is an exercise in which people and people compete, as well as exercise without equipment, exercise using equipment, and exercise with animals, and it is an exercise that includes static and dynamic exercise. The ethical issues of modern pentathlon athletes are also related to the poor environment and economic reasons, and the athlete's ethical awareness, attitude, and spirit have a great influence on the athlete's mental environment. In this study, the direction of improvement of ethical problems, which are different as important issues in modern sports, was examined, and qualitative research methods were applied to explore the sports spirit and ethics of the modern pentathlon. Correct sports should not deviate from the intended purpose of the exercise or cause or force the athlete to suffer physical or mental pain. In sports, compensatoryism can be a direct cause of improved performance or record-breaking, but sometimes it can also cause distorted athletes. Air doping has ethical issues that can cause controversy over the health or fairness of athletes, mental and physical damage to athletes, and harm. Responsibilities and ethical issues of athletes who take prohibited substances or leaders or supervisors who neglect or encourage them should be treated as very important matters. In the sports field, the reward system that is subordinate to the athlete's or leader's performance is related to the athlete's or leader's livelihood. For a fair and just game progression, it is necessary to break away from the development of athletes who are only focused on performance. The problem of Unethical issues must be overcome by emphasizing the restoration of ethics that are reasonably recognized in ideology and logic.
  • 15.

    Real-time Laying Hens Sound Analysis System using MFCC Feature Vectors

    Heung Seok Jeon | Deayoung Na | 2021, 26(3) | pp.127~135 | number of Cited : 0
    Abstract PDF
    Raising large numbers of animals in very narrow environments such as laying hens house can be very damaged from small environmental change. Previously researched about laying hens sound analysis system has a problem for applying to the laying hens house because considering only the limited situation of laying hens house. In this paper, to solve the problem, we propose a new laying hens sound analysis model using MFCC feature vector. This model can detect 7 situations that occur in actual laying hens house through 9 kinds of laying hens sound analysis. As a result of the performance evaluation of the proposed laying hens sound analysis model, the average AUC was 0.93, which is about 43% higher than that of the frequency feature analysis method.
  • 16.

    Effects of the Perceived Usefulness and Perceived Enjoyment of YouTube Use on Academic Adjustment of College Students in Distance Education due to COVID-19: Focusing on Compulsive YouTube Usage

    Jong Man Lee | 2021, 26(3) | pp.137~142 | number of Cited : 0
    Abstract PDF
    The goal of this study is to investigate how YouTube use motivation such as perceived usefulness and perceived enjoyment affect the compulsive YouTube usage and academic adjustment of college students. To this end, a research model was established and 113 response data obtained by conducting a questionnaire survey on college students in Seoul were used for structural model analysis. The results of this study can be summarized as following. First, perceived usefulness has a positive effect on academic adjustment. Second, compulsive YouTube usage has a negative effect on academic adjustment. Third, perceived enjoyment was identified as a factor that plays a role like pharmakon. The findings suggest the necessity of learning strategies that control the degree of perceived enjoyment as well as the instrumental use of perceived usefulness in order to improve the academic adjustment of college students.
  • 17.

    A Study on the Improvement of Police Committee System in Korea - Focus on the National Police Committee -

    Lee Young Woo | Su-Yeon Jang | 2021, 26(3) | pp.143~146 | number of Cited : 0
    Abstract PDF
    Korean police have been established as a national police system since the liberation of Korea and have been operated as a centralized police system for a long time, and a police committee was established under the enactment of the Police Act in 1991. However, the National Police Commission has a problem that it cannot perform the functions of the original National Police Commission because it is only a simple advisory body, not an institution that reviews and decides major policies related to police administration. As a result, despite the passage of a full amendment to the Police Act in 2020 and the revision of the Act to the Organization and Operation of the National Police and Local Police, operational and compositional problems still exist. Therefore, this study intends to propose the current state of operation and problems of the police committee system and measures for improvement.
  • 18.

    A Study on the Impact of Emotional Labor of Sales and Service Workers

    Bok Mi Jung | Hong, Eun-Sil | 2021, 26(3) | pp.147~154 | number of Cited : 0
    Abstract PDF
    The purpose of this study is to analyze the impact about emotional labor of sales service workers. Collected data were statistically processed by PASW 18.0 program using reliability, frequency analysis, T-test, one-way ANOVA, correlation and multiple regression analysis. The results were as follows. First, it was found that the sales service workers had higher deep acting than the surface acting of emotional labor. Second, it was found that altruism differed according to working period, conscientiousness according to gender, and work-family conflict according to age, marital status, and average customer response time per day. Third, the higher the surface acting of emotional labor, the higher the altruism. And the higher the deep acting, the less job burnout and work-family conflict decreased, and the altruism and conscientiousness increased. Fourth, as a result of analyzing the relative influence of variables related to emotional labor, the variable that has the greatest influence was the deep acting of emotional labor.
  • 19.

    A Study on the Proposal for Extension of Local Autonomy and Financial Atonomy of Local Education

    park | Sang-Ouk Noe | 2021, 26(3) | pp.155~165 | number of Cited : 0
    Abstract PDF
    The measures to extend local education autonomy are as follows: First, it is necessary to correct the confusion of the legal system of the local education autonomy system. For this, Article 12, Paragraph 2 and 4 of the 「Special Act on Local Autonomy and Decentralization, and Restructuring of Local Administrative Systems」 which state that “The State shall endeavor to consolidate systems for autonomy in education and local government” and “The implementation of autonomy in education and the autonomous police system shall be prescribed separately by Acts” should be deleted. Second, it is necessary to clarify unnecessary legal matters and regulatory measures for unification at the national level and to proactively consider the introduction of the legal trust system, in which education affairs are designated as local governments' own work and the state carries out specific affairs. The decentralization of local education finance is a key factor for the development of local education autonomy, and it requires the transfer of authority and resources to the region, and the enhancement of local autonomy and corresponding responsibility. First, the ratio of special grants must be adjusted further (from 3% to 2%) or the ratio of national policy projects must be lowered. Second, the provision that requires a consultation with a mayor/governor when making a budget covered by transfers from general accounts should be deleted. Third, it is necessary to remove the elements that limit the authority of city and provincial councils. Fourth, it is necessary to integrate the national education tax and the local education tax to create the education autonomy tax (tentative name) for only one independent purpose. Fifth, it is necessary to strengthen the distribution of the total amount of grants and abolish the settlement regulations for the measurement items of standard financial demand. Sixth is the expansion of the participation of stakeholders and experts in the grant distribution process. Seventh, it is necessary to establish a long-term employment system by designating the education finance field as a special field. Eight is the expansion of cooperative governance.
  • 20.

    Relationship between the creation of a child-friendly city and children's regional satisfaction, living satisfaction, and happiness

    Kyung-Suk Kim | 2021, 26(3) | pp.167~172 | number of Cited : 0
    Abstract PDF
    The purpose of this study is to present policy implications for the efficiency of child-friendly city creation through an empirical analysis of the relationship between variables related to the effectiveness of child-friendly city creation and the creation of child-friendly city. For this purpose, the difference between before and after the certification of child-friendly cities was analyzed for children of local governments certified as child-friendly cities. According to the analysis, the factors in the six major areas of child-friendly city creation do not significantly affect children's regional satisfaction, living satisfaction, and happiness. Based on these analysis results, the necessity of creating a child-friendly city and the direction related to the creation of a child-friendly city were presented. We also present the limitations of our research and future research challenges.
  • 21.

    The Effect of Quality Factors of Overseas Direct Purchase on Perceived Value and Purchase Intention: The Moderating Effect of Price Sensitivity

    Ji-Hee Jung | Jae-Ik Shin | 2021, 26(3) | pp.173~180 | number of Cited : 0
    Abstract PDF
    In this study, variables were constructed based on previous studies to examine the effects of overseas direct purchase quality factors(information quality, system quality, and service quality), perceived value, and purchase intention. In addition, differences between groups were examined through the moderating effect of price sensitivity. A survey was conducted on overseas direct purchase users, and 178 questionnaires were used for empirical analysis. The collected data was analyzed by SPSS 25.0 and AMOS 21.0. The results are as follows: First, it was found that the quality factors of overseas direct purchase had a positive effect on perceived value. Second, it was found that the quality factors of overseas direct purchase had a positive effect on purchase intention. Third, as a result of testing the moderating effect of price sensitivity in the relationship between the quality factors of overseas direct purchase, perceived value, and purchase intention, there was no difference between groups. In conclusion, the implications and limitations of this study are presented.