• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
• /
• pp.1193-1196
• /
• 2007

A new planar transformer type energy recovery circuit for PDP is proposed in this paper. The same current is transferred through both the primary and secondary sides during the energy recovery period. The conduction loss is reduced. Fabrication through simple manufacturing processes is possible using the PCB winding.

• 한국광학회지
• /
• 제18권3호
• /
• pp.185-189
• /
• 2007

평판형 AWG(Arrayed Waveguide Grating) 기술을 이용한 새로운 CWDM(Coarse Wavelength Division Multiplexer) 소자의 제작기술을 제안한다. 슬랩 도파로 입력단에 나팔형태를 갖는 도파로에 대하여 광전파방법(BPM)에 의한 전산모사 결과와 투과대역이 평탄화된 20 nm 간격의 CWDM 소자의 제작 결과를 보고한다. $0.75{\triangle}%$의 박막을 사용하였으며, 소자의 삽입손실은 가우시안 형태에 대하여 3.5 dB와 평탄화된 형태에 대하여 4.8 dB를 각각 얻었으며, 3 dB 대역폭은 각각 10 nm 및 13 nm 이상의 결과를 얻었다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
• /
• pp.489.2-489.2
• /
• 2014

The planar type flexible piezoelectric energy harvesters (PEH) based on PbZr0.52Ti0.48O3 (PZT) thin films on the flexible substrates are demonstrated to convert mechanical energy to electrical energy. The planar type energy harvesters have been realized, which have an electrode pair on the PZT thin films. The PZT thin films were deposited on double side polished sapphire substrates using conventional RF-magnetron sputtering. The PZT thin films on the sapphire substrates were transferred by PDMS stamp with laser lift-off (LLO) process. KrF excimer laser (wavelength: 248nm) were used for the LLO process. The PDMS stamp was attached to the top of the PZT thin films and the excimer laser induced onto back side of the sapphire substrate to detach the thin films. The detached thin films on the PDMS stamp transferred to adhesive layer coated on the flexible polyimide substrate. Structural properties of the PZT thin films were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). To measure piezoelectric power generation characteristics, Au/Cr inter digital electrode (IDE) was formed on the PZT thin films using the e-beam evaporation. The ferroelectric and piezoelectric properties were measured by a ferroelectric test system (Precision Premier-II) and piezoelectric force microscopy (PFM), respectively. The output signals of the flexible PEHs were evaluated by electrometer (6517A, Keithley). In the result, the transferred PZT thin films showed the ferroelectric and piezoelectric characteristics without electrical degradation and the fabricated flexible PEHs generated an AC-type output power electrical energy during periodically bending and releasing motion. We expect that the flexible PEHs based on laser transferred PZT thin film is able to be applied on self-powered electronic devices in wireless sensor networks technologies. Also, it has a lot of potential for high performance flexible piezoelectric energy harvester.

• 한국생산제조학회지
• /
• 제22권2호
• /
• pp.185-191
• /
• 2013

In this paper, the dynamics of a novel 2-DOF planar Translational Parallel Manipulator (TPM) is analyzed. The suggested TPM is made up of two PPa (Prismatic-planar Parallelogram) legs. Since all the linear actuators are mounted on the base, the proposed TPM can be applied for high speed positioning applications. The Lagrangian equations of the first type is employed to derive the inverse dynamic equations. It is shown that the analytical inverse dynamics equations match very well with ADAMS simulations. These analytical inverse dynamics equations will be used for the real-time computed torque control in the further work.

• 대한전자공학회논문지TC
• /
• 제41권6호
• /
• pp.79-86
• /
• 2004

정확한 closed-form 근린함수 계산방법은 공간영역 그린함수에 포함된 Sommerfeld 적분의 계산시간을 줄이기 위해 기존에 이용되어온 복소 영상법(Complex image method)과 2단계 근사화법(Two-level approach)에 비해 훨씬 적은 오차를 갖는다. 본 논문에서는 정확한 closed-form 그린함수 계산방법을 일반적인 전원을 포함하는 평판구조에 적용하는 방법을 제안하였다.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2008년도 추계학술대회A
• /
• pp.822-826
• /
• 2008

A linkage mechanism is a device to convert an input motion into a desired output motion. Traditional linkage mechanism designs are based on trial and error approaches so that size or shape changes of an original mechanism often result in improper results. In order to resolve these problems, an improved automatic mechanism synthesis method that determines the linkage type and dimensions by using an optimization method during the synthesis process has been proposed. For the synthesis, a planar linkage is modeled as a set of rigid blocks connected by zero-length translational springs with variable stiffness. In this study, the sizes of rigid blocks were also treated as design variables for more general linkage synthesis. The values of spring stiffness and the size of rigid block yielding a desired output motion at the end-effecter are found by using an optimization method.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2011년도 추계학술대회
• /
• pp.58-59
• /
• 2011

유전체 위에 구성된 마이크로 스트립 선로는 그 구성 형태에 따라 안테나, 통신용 필터, 공진기 등으로 응용할 수 있다. 그러나 최근 스트립 선로의 집적화 과정과 소형화와 관련하여 X 밴드 이상에서 구동되는 경우에는 선로의 곡각지점에서 불필요한 신호 누설로 인하여 다른 선로에 영향을 미치거나 EMC 등의 문제 등을 야기 시킨다. 본 연구에서는 유전체 위에 구성된 스트립 선로의 곡각지점에서의 신호 전달에 따른 영향을 조사하였다.

• Transactions on Electrical and Electronic Materials
• /
• 제17권1호
• /
• pp.50-55
• /
• 2016

In this paper, we have analyzed the electrical characteristics of 1200V trench gate field stop IGBT and have compared to NPT planar type IGBT and NPT planar field stop IGBT. As a result of analyzing, we obtained superior electrical characteristics of trench gate field stop IGBT than conventional IGBT. To begin with, the breakdown voltage characteristic was showed 1,460 V and on state voltage drop was showed 0.7 V. We obtained 3.5 V threshold voltage, too. To use these results, we have extracted optimal design and process parameter and designed trench gate field stop IGBT. The designed trench gate IGBT will use to inverter of renewable energy and automotive industry.

• Earthquakes and Structures
• /
• 제8권3호
• /
• pp.555-572
• /
• 2015

This paper presents an experimental study of three two-dimensional (2D/planar) steel reinforced concrete (SRC) T-shaped column-RC beam hybrid joints and six 3D SRC T-shaped column-steel beam hybrid joints under low cyclic reversed loads. Considering different categories of steel configuration types in column cross section and horizontal loading angles for the specimens were selected, and a reliable structural testing system for the spatial loading was employed in the tests. The load-displacement curves, carrying capacity, energy dissipation capacity, ductility and deformation characteristics of the test subassemblies were analyzed. Especially, the seismic performance discrepancies between planar hybrid joints and 3D hybrid joints were intensively compared. The failure modes for planar loading and spatial loading observed in the tests showed that the shear-diagonal compressive failure was the dominating failure mode for all the specimens. In addition, the 3D hybrid joints illustrated plumper hysteretic loops for the columns configured with solid-web steel, but a little more pinched hysteretic loops for the columns configured with T-shaped steel or channel-shaped steel, better energy dissipation capacity & ductility, and larger interlayer deformation capacity than those of the planar hybrid joints. Furthermore, it was revealed that the hysteretic loops for the specimens under $45^{\circ}$ loading angle are generally plumper than those for the specimens under $30^{\circ}$ loading angle. Finally, the effects of steel configuration type and loading angle on the seismic damage for the specimens were analyzed by means of the Park-Ang model.

• 한국수소및신에너지학회논문집
• /
• 제20권4호
• /
• pp.300-308
• /
• 2009

In a pursuit of the development of alternative mobile power sources with a high energy density, a planar and air-breathing PEMFCs with a new type of hydrogen cartridge which uses onsite $H_2$ generated from sodium borohydride ($NaBH_4$) hydrolysis have been investigated for use in advanced power systems. Two types of $H_2$ generation through $NaBH_4$ hydrolysis are available: (1) using organic acids such as sulphuric acid, malic acid, and sodium hydrogen carbonate in aqueous solution with solid $NaBH_4$ and (2) using solid selected catalysts such as Pt, Ru, CoB into the stabilized alkaline $NaBH_4$ solution. It might therefore be relevant at this stage to evaluate the relative competitiveness of the two methods mentioned above. The effects of flow rate of stabilized $NaBH_4$ solution, MEA (Membrane Electrode Assembly) improvement, and type and flow control of the catalytic acidic solution have been studied and the cell performances of the planar, air-breathing PEMFCs using $NaBH_4$ has been measured from aspects of power density, fuel efficiency, energy density, and fast response of cell. In our experiments, planar, air-breathing PEMFCs using $NaBH_4$ achieved to maximum power density of 128mW/$cm^2$ at 0.7V and energy efficiency of 46% and has many advantages such as low operating temperature, sustained operation at a high power density, compactness, the potential for low cost and volume, long stack life, fast star-up and suitability for discontinuous operation.