• Title/Summary/Keyword: Expansion Devices

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An Analysis of Satellite Communications System structure for NCW (NCW대비 군 위성통신 구조 분석)

  • Park, Woo-Chul;Cha, Jae-Ryong;Kim, Jae-Hyun
    • Journal of Satellite, Information and Communications
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    • v.4 no.1
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    • pp.1-7
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    • 2009
  • As the information age comes out, the aspect of future war brings about the many changes in terms of war-fighting environment. Accordingly, information superiority and intelligence-centric warfare have been important and new war-fighting concept such as NCW(network centric warfare) have been turned up. This paper proposed all-weather core-strategy communications systems guaranteeing not only the real-time transmission of the information collected in a battlefield and expansion, automation, and rapidity of a battlefield but also broadband, mobility, survivability, and flexibility. The proposed military satellite communications system is classified into wideband mass capacity link, survivability, and the system supporting OTM(on the move) communication for the real-time transmission of battlefield information. This paper analyzed the essential operation concepts and core schemes of the U.S. Army's next generation system, TSAT(Transformational Satellite Communication System). Base on the analysis results, this paper proposed that the architecture of next generation military satellite communications systems for NCW have to provide the data rate, anti-jamming capability, network control and management capability which are optimally adaptable for the wireless channel environments such as jamming and interference and to support the variety of platforms like high-speed mobile vehicles, micromini devices, super-high speed unmanned aerial vehicles. Finally, this paper also proposed that next generation military satellite communications systems need the technologies such as the adaptable multi-antenna, laser link, and next-generation anti-jamming waveform.

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Retail-Store Type Digital Signage Solution Development And Usability Test Using Android Mini PC (안드로이드 미니PC를 이용한 Retail-Store형 디지털사이니지 솔루션 개발 및 사용성 테스트)

  • Lim, Jungtaek;Shin, Dong-Hee
    • The Journal of the Korea Contents Association
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    • v.15 no.4
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    • pp.29-44
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    • 2015
  • Digital Signage, a way of advertising or delivering information to viewers through digital displays, has expanded from being just an advertising channel in public places. Recently, it has become widely prevalent in restaurants and retail stores. Despite its wide expansion, digital signage is limited to specific usages and services and the devices it uses are also quite expensive. This study introduces a stick-type digital signage product that operates on Android OS, which addresses all the weaknesses of digital signage with much more reasonable pricing and stable operation. For stability, performance tests were executed on the hardware and applications. The results for hardware performance were extremely promising, as each scenario's maximum performance results, measured by Load Runner programs, reached target indexes. Also, as a result of the usability test, all participants, including non-digital signage system users (novices), were able to easily learn all the tasks. As a result of user satisfaction survey, positive responses were exhibited for ease of learning and usability (LEU), helpfulness and problem solving capabilities (HPSC), affective aspect and multimedia properties (AAMP), commands and minimal memory load (CMML), and control and efficiency (CE).

Comparison of growth and properties of GaN with various AlN buffer layers on Si (111) substrate (Si (111) 기판 위에 다양한 AIN 완충층을 이용한 GaN 성장과 특성 비교)

  • 신희연;이정욱;정성훈;유지범;양철웅
    • Journal of the Korean Vacuum Society
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    • v.11 no.1
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    • pp.50-58
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    • 2002
  • The growth of GaN films on Si substrate has many advantages in that Si is less expensive than sapphire substrate and that integration of GaN-based devices with Si substrate is easier The difference of lattice constant and thermal expansion coefficient between GaN and Si is larger than those between GaN and sapphire. However, which results in many defects into the grown GaN. In order to obtain high duality GaN films on Si substrate, we need to reduce defects using the buffer layer such as AlN. In this study, we prepared three types of AlN buffer layer with various crystallinity on Si (111) substrate using MOCVD, Sputtering and MOMBE methods. GaN was grown by MOCVD on three types of AlN/Si substrate. Using TEM and XRD, we carried out comparative investigation of growth and properties of GaN deposited on the various AlN buffers by characterizing lattice coherency, crystallinity, growth orientation and defects formed (voids, stacking faults, dislocations, etc). It is found that the crystallinity of AlN buffer layer has strong effects on growth of GaN. The AlN buffer layers grown by MOCVD and MOMBE showed the reduction of out-of-plane misorientation of GaN at the initial growth stage.

A High Yield Rate MEMS Gyroscope with a Packaged SiOG Process (SiOG 공정을 이용한 고 신뢰성 MEMS 자이로스코프)

  • Lee Moon Chul;Kang Seok Jin;Jung Kyu Dong;Choa Sung-Hoon;Cho Yang Chul
    • Journal of the Microelectronics and Packaging Society
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    • v.12 no.3 s.36
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    • pp.187-196
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    • 2005
  • MEMS devices such as a vibratory gyroscope often suffer from a lower yield rate due to fabrication errors and the external stress. In the decoupled vibratory gyroscope, the main factor that determines the yield rate is the frequency difference between the sensing and driving modes. The gyroscope, fabricated with SOI (Silicon-On-Insulator) wafer and packaged using the anodic bonding, has a large wafer bowing caused by thermal expansion mismatch as well as non-uniform surfaces of the structures caused by the notching effect. These effects result in large distribution in the frequency difference, and thereby a lower yield rate. To improve the yield rate we propose a packaged SiOG (Silicon On Glass) technology. It uses a silicon wafer and two glass wafers to minimize the wafer bowing and a metallic membrane to avoid the notching. In the packaged SiOG gyroscope, the notching effect is eliminated and the warpage of the wafer is greatly reduced. Consequently the frequency difference is more uniformly distributed and its variation is greatly improved. Therefore we can achieve a more robust vibratory MEMS gyroscope with a higher yield rate.

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Effects of Nano Silica and Siloxane on Properties of Epoxy Composites for Adhesion of Micro Electronic Device (나노 실리카 및 실록산이 초소형 전자소재 접착제용 에폭시 복합재의 물성에 미치는 효과)

  • Lee, Donghyun;Kim, Daeheum
    • Korean Chemical Engineering Research
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    • v.47 no.3
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    • pp.332-336
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    • 2009
  • When NCAs(non-conductive adhesives) are used for adhesion of micro-electronic devices, they often show problems such as delamination and cracking, due to the differences of CTE(coefficients of thermal expansion) between NCAs and substrates. Additions of inorganic particles or flexibilizers have been performed to solve those problems. The effects of silica addition on thermal/mechanical properties of amino modified siloxane(AMS)/silica/epoxy-nanocomposites were examined. The silica was treated by 3-glycidoxypropyltrimethoxysilane(GPTMS) for better compatibility between silica and epoxy matrix. AMS/silica/epoxy-nanocomposites filled with various amounts of AMS(1 and 3 phr) and various amounts of silica(3, 5 and 7 phr) were prepared. And Tg, moduli and CTE of nanocomposites were analyzed. Tg of AMS/Aerosil(non-modified silica)/epoxy-nanocomposites decreased from 125 to $118^{\circ}C$ with increasing Aerosil contents and moduli increased from 2,225 to 2,523 MPa with increasing Aerosil contents. Tg of AMS/M-silica (modified silica)/epoxy-nanocomposites decreased from 124 to $120^{\circ}C$ with increasing M-silica contents and moduli increased from 1,981 to 2,743 MPa with increasing M-silica contents. CTE of AMS/Aerosil/epoxy-nanocomposites and AMS/M-silica/epoxy-nanocomposites showed decreasing tendency regardless of the surface treatments.

Limitations and Challenges of Game Regulatory Law and Policy in Korea (현행 게임규제정책의 한계와 과제 : 합리적인 규제를 위한 고려사항)

  • Kwon, Hun-Yeong
    • Journal of Information Technology Services
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    • v.13 no.3
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    • pp.149-164
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    • 2014
  • The laws and policies governing Korea's game regulations are becoming more and more topics for debate as we enter the Age of Internet. The nature of the basis for Internet regulations and policies are not rooted in freedom of speech or fundamental values of democracy, but rather focused on solving real-world problems such as protection of the youth. Furthermore, the reality is that regulatory devices for keeping the social order such as regulating gambling are being applied directly to games without consideration on the characteristics of Internet gaming, raising concerns that the expansion of constitutional values and innovative empowerment inherent to the Internet are being weakened. The Geun-Hye Park Administration which succeeded Myung-Bak Lee's Administration, even went so far as to implement the so-called "Shutdown Policy", which prohibits access to Internet games during pre-defined time zones and also instigated a time zone selection rule. In order to curb the gambling nature of Internet games, government-led policies such as the mandatory personal identification and prohibition of player selection or in other words mandatory random player selection are being implemented. These institutions can inhibit freedom of speech, which is the basis of democracy, violate the right of equality through unreasonable discrimination between domestic and foreign service providers, and infringe upon the principles of administrative law, such as laws, due process in policies, and balance in among policies and governmental bodies. Going forward, if Korea's Internet game regulations and polices is to develop in a rational manner, regulatory frameworks will need to be designed to protect the nature of the Internet and its innovative values that enable the realization of constitutional values; for example, the Internet acting as the "catalytic media for freedom of expression as a fundamental human right ", which has already been acknowledged by the Korea's Constitutional Court. At the same time, transparent procedures should be put into place that will allow diverse participation of stakeholders including game service providers, game users, the youth and parents in the legislation and enforcement process of regulatory institutions; policies will also need to be transformed to enable not only regulatory laws but also self-regulation system to be established. And in this process, scientific and empirical analysis on the expected effects before introducing regulations and the results of enforcing regulations after being introduced will need to be strengthened.

A Study on the Cobalt Electrodeposition of High Aspect Ratio Through-Silicon-Via (TSV) with Single Additive (단일 첨가제를 이용한 고종횡비 TSV의 코발트 전해증착에 관한 연구)

  • Kim, Yu-Jeong;Lee, Jin-Hyeon;Park, Gi-Mun;Yu, Bong-Yeong
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2018.06a
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    • pp.140-140
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    • 2018
  • The 3D interconnect technologies have been appeared, as the density of Integrated Circuit (IC) devices increases. Through Silicon Via (TSV) process is an important technology in the 3D interconnect technologies. And the process is used to form a vertically electrical connection through silicon dies. This TSV process has some advantages that short length of interconnection, high interconnection density, low electrical resistance, and low power consumption. Because of these advantages, TSVs could improve the device performance higher. The fabrication process of TSV has several steps such as TSV etching, insulator deposition, seed layer deposition, metallization, planarization, and assembly. Among them, TSV metallization (i.e. TSV filling) was core process in the fabrication process of TSV because TSV metallization determines the performance and reliability of the TSV interconnect. TSVs were commonly filled with metals by using the simple electrochemical deposition method. However, since the aspect ratio of TSVs was become a higher, it was easy to occur voids and copper filling of TSVs became more difficult. Using some additives like an accelerator, suppressor and leveler for the void-free filling of TSVs, deposition rate of bottom could be fast whereas deposition of side walls could be inhibited. The suppressor was adsorbed surface of via easily because of its higher molecular weight than the accelerator. However, for high aspect ratio TSV fillers, the growth of the top of via can be accelerated because the suppressor is replaced by an accelerator. The substitution of the accelerator and the suppressor caused the side wall growth and defect generation. The suppressor was used as Single additive electrodeposition of TSV to overcome the constraints. At the electrochemical deposition of high aspect ratio of TSVs, the suppressor as single additive could effectively suppress the growth of the top surface and the void-free bottom-up filling became possible. Generally, copper was used to fill TSVs since its low resistivity could reduce the RC delay of the interconnection. However, because of the large Coefficients of Thermal Expansion (CTE) mismatch between silicon and copper, stress was induced to the silicon around the TSVs at the annealing process. The Keep Out Zone (KOZ), the stressed area in the silicon, could affect carrier mobility and could cause degradation of the device performance. Cobalt can be used as an alternative material because the CTE of cobalt was lower than that of copper. Therefore, using cobalt could reduce KOZ and improve device performance. In this study, high-aspect ratio TSVs were filled with cobalt using the electrochemical deposition. And the filling performance was enhanced by using the suppressor as single additive. Electrochemical analysis explains the effect of suppressor in the cobalt filling bath and the effect of filling behavior at condition such as current type was investigated.

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Research on the Curriculum for Integration of ICT+Design (ICT+디자인 융합 교육과정 개발연구)

  • Jeong, Sang-Hoon
    • Science of Emotion and Sensibility
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    • v.20 no.1
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    • pp.105-114
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    • 2017
  • Nowadays, novel and innovative technology including 3D printers, internet of things (IoT), and wearable devices are rapidly emerging. As we must constantly keep up with the most recent trends, words like convergence, multidisciplinarity, and design revolution indeed define society today. Due to the expansion of such diverse technological, industrial, and academic convergence trends, the role of design is becoming evermore essential in development of products as well as creative services. Even the government is pushing towards a 'creative economy' by encouraging ICT convergence to create novel industries as well as advanced jobs. In order to adapt flexibly to such changes in global trends, a solid academic curriculum centered around 'ICT+Design' must be developed. In the current research, we analyzed various literature and benchmarked the major universities both domestic and foreign. Also we utilized a survey-based approach against subjects who are experts or design specialists working in environments related to industry and research. In our proposed integrated ICT+Design educational curriculum, students familiarize themselves with design perspectives and methodology to creatively carry out the course. Moreover, experts from design and ICT came together in an act of 'Radical Collaboration' in which they shared their unique 'Design Thinking' in order to promote understanding and cooperation. Furthermore, industry experts have also taken part as mentors in order to create a workplace-oriented course with various integrated projects. Most importantly, the course was designed so that in addition to research, students can really get hands-on with their ideas in the creativity-integrated workplace.

Design and Development of Personal Healthcare System Based on IEEE 11073/HL7 Standards Using Smartphone (스마트폰을 이용한 IEEE 11073/HL7 기반의 개인 건강관리 시스템 설계 및 구현)

  • Nam, Jae-Choong;Seo, Won-Kyeong;Bae, Jae-Seung;Cho, You-Ze
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.12B
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    • pp.1556-1564
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    • 2011
  • The increased life expectancy of human due to the advance of medical techniques has led to many social problems such as rapidly aging populations, increased medical expenses and a lack of medical specialists. Thus, studies on improving the quality of life with the least amount of expense have been going on by incorporating advanced technologies, especially for Personal Health Devices (PHDs), into the medical service market. However, compatibility and extensibility among manufacturers of PHDs have not been taken into account in most of the researches done on the development of PHDs because most of them have been supported by individual medical organizations. The interoperability among medical organizations can not be guaranteed because each medical organization uses different format of the messages. Therefore, in this paper, an expansion module that can enable commercially-available non-standard PHDs to support the IEEE 11073, and a smart-phone-based manager that can support easy and comprehensive management on receiving and transmitting the collected data from each PHD using IEEE 11073 standard were developed. In addition, a u-health system that can transmit the data collected in the manager using the standard data format HL 7 to medical center for real-time medical service from every medical institutions that support this standard was designed and developed.

History of Domestic Web Design - Focused on Design Expression Techniques and Technological Changes - (국내 웹 디자인 변천사 - 디자인 표현기법과 기술적 변화를 중심으로 -)

  • Lee, HyunJu;Hong, MiHee
    • The Journal of the Korea Contents Association
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    • v.20 no.3
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    • pp.200-208
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    • 2020
  • The domain of Web design gradually expands with the utilization of the Web and the development of technologies, but there are insufficient related studies. Thus, this study would recognize the importance of the Web design market and present the direction of designs in the future by investigating the process of changes in Web design. This study investigated the background of the revelation and evolution of design expression techniques and the flow of the information technology affecting the design and conducted a study analyzing the process of changes of Web design based on this. It is judged that this study has significance as the baseline research material for the expansion of the Web design domain of the future. As for the scope of the research, based on 30 years of the history of the Web, this study was conducted with materials on Websites, which had become issues from 1990 through the early-2000s and selected the winners of a grand prize in Web Award Korea since the mid-2000s as the subjects of analysis. This study analyzed the formative characteristics of design expression techniques and the characteristics of the information technology that affected Web design. As a result of the research, changes in design expression techniques could be divided broadly into minimalism and skeuomorphism, and it was found that the methods of expressing Web designs changed in various ways, affected by the development of information technology. It is predicted that with the emergence of various devices and the vitalization of video contents, the designs affected by minimalism, which can harmonize with them, will continue in the future.