• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제10권8호
• /
• pp.3435-3454
• /
• 2016

Device-to-device (D2D) communication is a potential solution to the incessant increase in data traffic on cellular networks. The greatest problem is how to control the interference between D2D users and cellular mobile users, and between D2D users themselves. This paper proposes a solution for this issue by putting the full control privilege in cellular network using the software-defined networking (SDN) concept. A software virtual switch called Open vSwitch and several components are integrated into mobile devices for data forwarding and radio resource mapping, whereas the control functions are executed in the cellular network via a SDN controller. This allows the network to assign radio resources for D2D communication directly, thus reducing interference. This solution also brings out many benefits, including resource efficiency, energy saving, topology flexibility, etc. The advantages and disadvantages of this architecture are analyzed by both a mathematical method and a simple implementation. The result shows that implementation of this solution in the next generation of cellular networks is feasible.

• Transactions on Electrical and Electronic Materials
• /
• 제12권2호
• /
• pp.43-50
• /
• 2011

Carbon-nanotube metal oxide semiconductor field effect transistor (CN-MOSFET) is a promising future device candidate. The electrical characteristics of 16 nm N-type CN-MOSFETs are explored in this paper. The optimum N-type CN-MOSFET device profiles with different number of tubes are identified for achieving the highest on-state to off-state current ratio ($I_{on}/I_{off}$). The influence of substrate voltage on device performance is also investigated in this paper. Tradeoffs between subthreshold leakage current and overall switch quality are evaluated with different substrate bias voltages. Technology development guidelines for achieving high-speed, low-leakage, area efficient, and manufacturable carbon nanotube integrated circuits are provided.

• 한국항행학회논문지
• /
• 제12권5호
• /
• pp.444-450
• /
• 2008

유무선 통합 환경의 도래와 모바일 디바이스의 대중화로 모바일 환경에서 디바이스를 이용한 다양한 서비스를 제공받고자 하는 수요가 급속도록 증가하고 있다. 그러나 모바일 환경에서는 유선 환경의 보안 위협사항 뿐만 아니라 무선 화경에서 나타날 수 있는 많은 위협에 노출되어 있다. 이러한 문제점에 따라 모바일 환경에서 디바이스를 이용해 서비스를 제공받는데 있어 안전하고 효율적인 보안 기술이 필요하다. 따라서 본 논문에서는 모바일 환경에서 안전한 서비스 제공을 위해 AAA (Authentication, Authorization, Accounting) 메커니즘에서 디바이스 인중 기술에 관한 연구를 진행한다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
• /
• pp.312-315
• /
• 2001

Recently organic electroluminescent devices have been intensively investigated for using in full-color flat-panel display. Since the quantum efficiency of electrophosphorescent device decrease rapidly as the luminance increase, it is desirable to operate the electrophosphorescent display with active matrix rather than passive matrix. Here we report the study of driving electrophosphorescent diode with all organic thin film transistor(OTFT). The structure of electrophosphorescent diode is ITO/TPD/BCP:Ir(ppy)$_3$/BCP/Alq$_3$/Li:Al/Al. In OTFT. polymer is used as an insulator and pentacene as an active layer. Detailed performance of the integrated device will be discussed.

• 한국생산제조학회지
• /
• 제22권3_1spc호
• /
• pp.531-536
• /
• 2013

An automatic wax-ring manufacturing system for silk coating was developed, which consisted of a container, pallet with a cooling part, injection port, and removing device. The removing device is a system to load, lift, and cut the wax-ring, which is widelyused for various silk-coating industrial purposes. A novel removing device equipped with a water cooling circulation system is proposed in this paper. It has the benefit of easy control, as well as the convenience of loading and unloading without the use of other equipment. Three-dimensional modeling techniques were adopted to develop integrated functions for the automatic wax-ring manufacturing system, which made it possible to confirm the smooth integration/interface of each part and the system's interrelations with other manufacturing systems.

• 한국기계가공학회지
• /
• 제9권1호
• /
• pp.61-66
• /
• 2010

Pay off reel is the device to release in the form of coil. Every time the device becomes a hassle to exchange, each diameter of two forms has been applied to the coil reel. There is the change of reel diameter of the sleeve portion to be the part of segment geometry. This unit is conducting on 3-dimensional modeling design. The basic strength and deformation of the device could be checked in advance by the basis of 3-d modeling data to perform simulations. The production of each part can be completed and assembled. Conducted for the final product which is tested and measured, all items are satisfied within the limits of targets. Due to the development of this device, the efficiency on operations can be increased and the production time becomes shortened.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2006년도 추계학술대회 논문집
• /
• pp.238-244
• /
• 2006

The Light Collision Safety Device is used to protect the important part of trains and passengers at the low velocity accidents. The Light Collision Safety Device comprises mainly tension bolts, shear bolts and an energy absorber. The work mechanism of this device is that first, the tension bolts break at designed collapse load and second, the energy absorber absorb rest collision energy. In this paper, the tension bolt characteristics were validated by the simple tension test using the FEM(Finite Element Method) and the characteristic of the two types of energy absorber were compared by using the load-displacement curves and absorbed energy. Last, in order to determine integrated load-displacement curve of tension bolts and the energy absorber, the unified analysis was conducted by using the FEM.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2001년도 추계학술대회 논문집
• /
• pp.312-315
• /
• 2001

Recently organic electroluminescent devices have been intensively investigated for using in full-color flat-panel display. Since the quantum efficiency of electrophosphorescent device decrease rapidly as the luminance increase, it is desirable to operate the electrophosphorescent display with active matrix rather than passive matrix. Here we report the study of driving electrophosphorescent diode with all organic thin film transistor(OTFT). The structure of electrophosphorescent diode is ITO/TPD/BCP:Ir(ppy)$_3$/BCP/Alq$_3$/Li:Al/Al. In OTFT, Polymer is used as an insulator and pentacene as an active layer. Detailed performance of the integrated device will be discussed.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 제38회 하계학술대회
• /
• pp.648-649
• /
• 2007

변전소의 설비 관리/진단 및 보호, 감시, 제어 등의 자동화 시스템인 SAS(Substation Automation System)의 운영에 있어서 가장 중요한 요인은 System의 신뢰성 확보라 할 수 있다. 즉, Real-time Data에 대한 정확하고 빠른 취득능력은 SAS의 평가 잣대가 될 수 있다. 따라서 SAS 운영의 신뢰성을 증대시키기 위해 상위 HMI(Human Machine Interface)와 하위 Device간의 통신 중계 역할을 하는 I/O Server의 Virtual Simulation Environment인 Hyosung 통합 I/O Server Toolkit(Virtual Device 포함)을 개발하였다.

• International Journal of Computer Science & Network Security
• /
• 제21권1호
• /
• pp.152-161
• /
• 2021

The paper focuses on Device-to-device (D2D) Architectures evaluation frameworks. D2D communication and discovery can improve spectrum usage efficiency and optimize the tradeoffs between throughput and energy consumption. The target operation modes involve both indirect communication between two nodes via a base station or the direct communication among proximal nodes, enabling use cases that can support communications out of cellular coverage, as well as low end-end delay requirements. The paper will present the architectural evolution of D2D networks within 3GPP standardization and will highlight key network functionalities and signaling protocols. It will also identify key analytical and simulation models that can be used to assess the performance and energy efficiency of resource allocation strategies, and it will present a suitable cross-layer integrated framework.