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pISSN : 1975-7700 / eISSN : 2734-0570

2020 KCI Impact Factor : 0.42
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2017, Vol.12, No.4

  • 1.

    A Study on The Fun Elements of Social Platform - Focused on Nicole Lazzaro’s Fun Theory

    조래을 | 2017, 12(4) | pp.473~482 | number of Cited : 2
    Abstract PDF
    The rapid development of information and communication technology has brought about a great change in the global industry. The birth of a smart phone has created many new businesses with a new paradigm that transcends the time and space that can be accessed anytime and anywhere through ubiquity, portability and wireless connection beyond the concept of time and space. A positive network is created with the rapid growth of social network sites, like Kakao, Facebook etc.. In addition to this, Platform Thinking, a social platform based on the service network, is becoming a big axis of the industry. In order to find out the fun factors among the characteristics of the social platforms and to reveal the fun factors according to the functions of the social platform as fun theories, We will clarify the characteristics and the factors affecting them. This is a study on social platform, which is based on SNS, and we want to study emotional fun factor of social platform. In the preliminary study, it was found that consumers enjoy the fun through video and social games on social platforms. In this study, the four fun elements(Hard fun, Easy fun, Serious fun, People fun) of Nicole Lazzaro are applied to the fun emotion that users enjoy through social platforms. As a result of research, it is possible to utilize various functions of social platform and achievement feeling of uploading videos and photos using various functions(hard fun), curiosity to find new information and new friends(easy fun), satisfaction to receive responses such as 'likes' and 'feelings'(serious fun), communication with reply and answer comments(people fun).
  • 2.

    IoT-based Support System Design of Automated Cremation Process Guide

    Hee Rak Lee | Kim Jae Woong | 2017, 12(4) | pp.483~489 | number of Cited : 0
    Abstract PDF
    Changes in trends and national sentiment are gradually changing funeral culture from burial to cremation. A number of cremation facilities are newly introduced to the funeral facilities and the number of cremation is increasing every year. As the number of visitors to cremation facilities increases, the need for proper guidance systems is also increasing. However, cremation facilities at Funeral Cultural Center are not equipped with automation due to the nature of facilities. Even if it is equipped, the automation is insufficiently applied. In this paper, We suggest a solution of the problem that the ending signal is not generated by the different business process as per each cremation object in the cremation facility adopting the automation system. We would like to design the system which mounts IoT-based automation support module which guides cremation progress on the car using for funeral. The construction of the cremation progress guide automation system will provide precise progress to the mourners, simplify complicated procedures such as wired wireless communication between the managers in the field and the management room, and reduce the burden on the field support personnel. The support system is designed to be lightweight and wireless so that it does not interface with the cremation work.
  • 3.

    Development of an Adaptive Lens Using an Ionic Polymer-metal Composite

    신은재 | 박원형 | 여명 and 2other persons | 2017, 12(4) | pp.491~500 | number of Cited : 0
    Abstract PDF
    The optical focus variable lenses have been widely used in consumer electronic devices to capture objects which are located in arbitrary position. These focus variable lenses are achieved by changing the distance between the two or more lenses or are made with electrowetting mechanism, liquid crystal material, or liquid with a pump. These lenses suffer from aberrations due to non-uniformities in the electric field and trouble with liquid evaporation. Another drawback of these focus variable lenses is to need an external mechanism (including actuators outside the optical path). In this paper, we present another type of lens using an electroactive polymer. The purpose of this paper is to describe self-deformable thin lens without any external mechanism. We fabricated an IPMC lens with blur-sharp effect. The IPMC lens is composed of both a thermally imprinted, transparent, and concave-structured Nafion membrane and partially electroless-plated the platinum electrode. By applying a low AC voltage to the IPMC lens, the IPMC deforms upward and downward for itself. As a result, the blur-sharp effect was obtained in the concave-structured Nafion membrane. The proposed method for fabricating blur-sharp effect lens has a large potential to realized very small electro-optics, especially in the field of consumer electronic devices.
  • 4.

    Implementation of Beamforming Butler Matrix(4×4) Based on Planar Structure for LTE Mobile Communications

    Dong Hak Lee | Doo-Yeong Yang | 2017, 12(4) | pp.501~511 | number of Cited : 1
    Abstract PDF
    In order to design a beamforming Butler matrix operating in the LTE band of 2.5-2.68GHz, the Butler matrix with a broadband structure was designed by constructing a hybrid coupler and crossover, which are components of Butler matrix, with a multistage branch line structure. The structure and components of the Butler matrix consist of four 3dB hybrid couplers, two crossovers, two -45˚ phase shifters and two equiphase controllers. Among these components, the 3dB hybrid coupler and crossover are designed to have broadband characteristics with a branch line structure in the microstrip substrate. The -45˚ phase shifter and equiphase controller adjust the length of the line to obtain the proper phase, respectively. The designed Butler matrix showed good return loss characteristics of 23.9-34.18dB and relatively small phase error of 5.41˚ in the operating band. And also, when the output signal of the Butler matrix was applied to the microstrip patch array antenna, the effect of the signal amplitude and phase error on beamforming pattern and beam steering direction were studied. As a result, when the Butler matrix has a phase error of about 5.41˚, the direction of the formed beam pattern does not largely change by an error of 1˚, and the beam can be properly steered in a desired direction.
  • 5.

    A Study of the Transfer Delay of ECMC in SCTP

    CHOI WON KEUN | SUNMOON JO | 2017, 12(4) | pp.513~519 | number of Cited : 0
    Abstract PDF
    The main challenge in the field of designing multimedia services is the integration and support of a wide variety of applications. Quality of Service(QoS) provides a unifying theme on which the functions and facilities of the open system standards can be constructed. In distributed multimedia system, QoS guarantees are fundamentally concerned with the end-to-end communication between applications. One of the important QoS parameters is the reliability of the transfer. Including SCTP(Stream Control Transport Protocol), conventional error control mechanisms, however, do not consider the integrated viewpoint of multimedia data. In paper[1], We have designed and proposed the multimedia oriented error control method based on multimedia characteristics called ECMC(Error Control based on Multimedia Characteristic). In this paper, We have investigated its transfer delay. The results show that the ECMC mechanism manifests superior performance as errors occur more frequently. When the frame transfer succeeds, it can be found that the ECMC mechanism reveals shorter average frame delay than SREC(Selective Repeat Error Control). On the other hand, the performance measurements on the both mechanisms show closer results as the error rate decreases. Furthermore, in the case of the extremely low error rate, the both mechanisms represent the almost same performance results. Therefore, it makes SCTP have the flexibility and high performance. It should have the reduction effect of the communication resources as well as satisfy the requirements of users.
  • 6.

    A Study on Secure Query Processing Technique for Efficient XML Resource Access

    SUNMOON JO | CHOI WON KEUN | 2017, 12(4) | pp.521~527 | number of Cited : 0
    Abstract PDF
    With the development of the mobile environment, it has become more common to access dynamic XML data regardless of location and time. As the application areas of XML are gradually expanding, the security issue of XML has become a major concern. XML is an important tool for storing and exchanging data. It also plays an important role in systems and web applications on the Internet. However, XML is just a language, so the security of the application can not be guaranteed. There are also problems such as permission to access resources, authentication, security enhancement and privacy protection. XML should be used to support access because protection can not be guaranteed due to some functions of the data while using the existing access uniquely. As this makes XML data increasingly complex, there is a growing demand for a secure access policy for data. Therefore, it is difficult to apply the existing access policy. The requirements of access in XML need to be integrated with Web technology support, transparency, fine access control, and existing user authorization techniques. In this paper, we propose a secure query processing technique for efficiently accessing large capacity XML data resources. We also analyze the existing problems and present experimental results through practical and important techniques and performance evaluation. Finally, we describe the direction of future research through secure XML access policy.
  • 7.

    Development of an Auto-Build and a Version Management System for a Fly-By-Wire Model of a Rotorcraft

    Ho-Chae Jung | BAEJONGMIN | 2017, 12(4) | pp.529~537 | number of Cited : 0
    Abstract PDF
    The dynamics models and the flight control models are developed on non-real time operating system environment in its first development step when we build a fly-by-wire flight control system. These models are built on a Handling Quality Simulator(HQS) in the next step which is a virtual simulator to be operated in real-time environment that is similar to the real system. A pilot makes quantitative and qualitative assessment for testing the controllability of the models operating in the HQS. In this case the model build process is complex and time consuming. Moreover it is difficult to compare the previous version of models because of the continuous model modifications. In this paper, we present design and implementation result of an auto-build tool which is used for building the flight control models and dynamic models on the top of the HQS, and also present the version management system of models which can be used for comparing models immediately. The auto-build tool can reduce model build time and enhance system reliability. It makes engineers concentrate on only model development itself. The version management system can reduce model testing time and make model insertion, modification and deletion easily. Thus our system can improve development productivity by reducing the model build and testing time.
  • 8.

    An Omnidirectional High Gain Antenna for UHF Band Ground Station

    Ki-Hyoung Bae | Min-Soo Chang | Jae-Woo Joo and 2other persons | 2017, 12(4) | pp.539~550 | number of Cited : 0
    Abstract PDF
    In this paper, we designed, fabricated and tested an UHF band cylindrical dipole array antenna. In the proposed antenna, cylindrical dipoles were vertically arranged in four stages. A parallel structure feeding circuit was installed inside the cylindrical dipole and mounted so as to be broadband matching. The feeding circuit was installed at the center of the cylindrical dipole to optimize the gain flatness characteristic of the azimuth direction omnidirectional radiation pattern. Minimizing the difference between the signals branched from the feeding circuit and realizing the symmetry of the radiation pattern. The required specifications are more than 11.2% bandwidth in UHF band, above 6dBi antenna gain, standing wave ratio of 2:1 or less, less than ±1dB gain flatness in azimuth radiation pattern, more than 13 degrees in elevation radiation pattern of 3dB beamwidth. We confirmed the possibility of implementation through M&S and verified the result of M&S through production and testing. The test results are 11.2% bandwidth in the UHF band, 6.30 to 8.31 dBi gain, 1.53:1 standing wave ratio or less, within ±0.2 dB gain flatness in the azimuth radiation pattern, elevation radiation pattern of 3dB beam width was 15.62 to 15.84 degrees. The test result meets all requirements specifications.
  • 9.

    The Development of Holography-based Ping Pong Game System using Hand Tracking Interaction

    Choi,Gil-Rim | Seung Jae Lee | HyunJu Kim | 2017, 12(4) | pp.551~558 | number of Cited : 0
    Abstract PDF
    Game services have thus far mostly provided images of 2D resources, but with users’ requests increasing for more real-sense contents and advancement in technology development, games have been able to provide 3D resources. However, to configure an environment identical with reality, a certain area for actual experience is required, which in turn must require the securing of broad space, making the attempt uneconomical. It is suggested that, as an alternative, virtual reality and augmented reality technologies can deliver images identical with reality, but this can only resolve the visual and auditory senses of senses experienced by humans. This paper constructed a system designed to play holography technology-based games using Kinect. As a result, we have enabled an efficient creation of space by using hologram-based images with a depth value as contents. In addition, By incorporating the user's hand tracking technology into games, using Kinect, we have configured games in such a way that they can be played by recognizing the hand movements of the user without requiring the user to wear complex interaction equipment. Thus, it was confirmed that it is possible to develop experiential workout games in which the user can not only take interest but have workout effects at low cost.
  • 10.

    Improvement of Selection Procedure for Network Separation Method by Using AHP

    Jae-Ho Lee | Lee Sang Joon | 2017, 12(4) | pp.559~569 | number of Cited : 1
    Abstract PDF
    As a result of the amendment of the relevant laws, the network separation has become legally mandatory. Many public institutions, financial institutions and private companies have adopted or are actively considering the network separation. Various studies have been carried out on network separation, but most studies are limited to individual network separation technology itself. Since there are no specific standards or procedures related to the selection and introduction of network separation methods, many organizations are having difficulty in network separating. In this paper, the factors to be considered in selecting the network separation method are derived by analyzing the characteristics of each network separation method, analyzing the characteristics of domestic and foreign products related to network separation, and analyzing the research results of related experts. In addition, AHP method was used to estimate the importance of these factors and to determine the priorities. The proposed method is applied to the organizations preparing to introduce the actual network separation, and it is verified that this method can be used to select the most suitable network separation method for the relevant organizations. In addition to selecting the network separation method, the proposed method can also be applied to general security product selection.
  • 11.

    Design and Implementation of Slot-coupled Microstrip Components for Wideband Butler Matrix

    Dong Hak Lee | Doo-Yeong Yang | 2017, 12(4) | pp.571~580 | number of Cited : 2
    Abstract PDF
    The design of a slot-coupled directional coupler and a slot-coupled crossover for use in a switched beamforming network operating over wideband has been presented and discussed. In order to achieve wideband characteristics, the coupler and the crossover use slot-coupled microstrip transmission line (MTL) technology. Since the slot-coupled components have a structure in which the two signal lines on the top and bottom side are coupled to each other through the rectangular slot on the common ground plane, the amount of the combined signal is determined by the width of the slot, the width of the line and the height of the substrate. The width of the slot should be set to be wider than the width of signal line to induce proper coupling, and the width of the slot should be about 1.5 times to the width of the signal line. It can be seen that the coupling coefficient increases as the ratio of the width of the line to the height of the substrate increases, which means that the amount of the signal coupled to the output port increases as the width of the line increases. The proposed coupler and the crossover have been obtained high performance of 3±0.5dB coupling, 90±1° phase difference, and 0.5dB coupling and 45±3.5° phase shift in the operating frequency band, respectively. In addition, they have been implemented on the double-layered MTL in a small size and without intersecting lines on microstrip substrate.
  • 12.

    Implementation of Slot-Coupled Broadband Butler Matrix Based on Multiple Layered Microstrip Transmission line

    Doo-Yeong Yang | Dong Hak Lee | 2017, 12(4) | pp.581~590 | number of Cited : 2
    Abstract PDF
    Switched beamforming network required for multiple input multiple output (MIMO) technology and smart antenna technology can adaptively adjust the beam direction of the array antenna according to the moving direction of the mobile station. Therefore, the proposed beamforming network called Butler matrix is a power feeding system capable of forming beams in various directions by adjusting the magnitude and phase of the feed signals applied to the array antenna. In this paper, a combination of microstrip slot-coupled directional couplers and slot-coupled crossovers including 45° phase shifter has been employed to expand the bandwidth of the 4x4 Butler matrix and reducing the number of conventional crossovers. The proposed slot-coupled components consist of two rectangular microstrip transmission lines (RMTLs) facing each other at the top and bottom layer and a common ground. The coupling between these RMTLs is achieved by cutting a rectangular slot in the ground plane which is located at the middle layer. A common ground is in a position between the two dielectrics. From the simulation and measurement results, the proposed Butler matrix has a good performance of broad fractional bandwidth of 43%, return loss of 15.5dB, insertion loss of 6.5±0.4dB and progressive phase shift of -45, 135, -135, 45 ±5° in 2.5~2.7GHz operating frequency band.
  • 13.

    A Design and Implementation of Cryptographic Processor DNAES Flexibly Internet of Things Network

    Sun-Yeob Kim | 2017, 12(4) | pp.591~597 | number of Cited : 0
    Abstract PDF
    With the rapid development of the Internet environment, the importance of security for terminals of wireless networks is increasing. In the case of a sensor node, which is often used as a wireless network terminal in the Internet environment, a resource environment such as a memory is poor. Therefore, there is a problem that a memory-intensive security algorithm can not be used. In this paper, we propose the DNAES algorithm considering the security problem when the number of sensors increases because it enables the poor resource environment, low power and high speed processing of sensor nodes. The proposed DNAES encryption algorithm adopts the DN-R technique which reduces the load of important nodes in the wireless network environment. Implementation of the DNAES encryption algorithm was performed using topology of verilog-HDL. The tool used for circuit synthesis was Synopsys Design Analyzer and QUARTUS 12.0. The tools used in the simulation were Synopsys VHDL Debugger, ModelSim 5.8C. Simulation results show that the proposed DNAES encryption algorithm has a 120% increase in throughput compared to the conventional AES algorithm. Therefore, it is considered that the DNAES proposed in this paper is sufficient for the security of the sensor node in the IOT environment.