• Journal of Power Electronics
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• 제9권2호
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• pp.308-319
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• 2009

An increasing number of power electronic applications require high power density. Therefore, the switching frequency and switching speed have to be raised considerably. However, the very fast switching transients induce a strong voltage and current ringing. In this work, a novel damping concept is introduced where the parasitic wiring inductances are advantageously magnetically coupled with a damping layer for attenuating these unwanted oscillations. The proposed damping layer can be implemented using standard materials and printed circuit board manufacturing processes. The system behavior is analyzed in detail and design guidelines for a damping layer with optimized RC termination network are given. The effectiveness of the introduced layer is determined by layout parasitics which are calculated by application of the Partial Element Equivalent Circuit (PEEC) simulation method. Finally, simulations and measurements on a laboratory prototype demonstrate the good performance of the proposed damping approach.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 춘계학술대회 논문집
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• pp.568-572
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• 2013

This is traffic noise reducing technology with higher porosity and durability by using small aggregate in upper layer and big aggregate in lower layer utilizing RSBS modifier. We can reduce average 9dB(A) of traffic noise compare to normal pavement by double layer structure with higher durability using small gap over bigger gap. Also, it increases a porosity more than 22% with more durability by RSBS modifier.

• 한국분말재료학회지
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• 제4권3호
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• pp.196-204
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• 1997

Joining of AIN ceramics to W and Cu by active-metal brazing method was tried with use of (Ag-Cu)-Ti alloy as insert-metal. Joints were produced under various conditions of temperature, holding time and Ti-content in (Ag-Cu) alloy Reaction and microstructural development in bonded interface were investigated through observation and analysis by SEM/EDS, EPMA and XRD. Joint strengths were measured by shear test. Bonded interface consists of two layers: an insert-metal layer of eutectic Ag- and Cu-rich phases and a reaction layer of TiN. Thickness of reaction layer increases with bonding temperature, holding time and Ti-content of insert-metal. It was confirmed that the growth of reaction layer is a diffusion-controlled process. Activation energy for this process was 260 KJ/mol which is lower than that for N diffusion in TiN. Maximum shear strength of 108 MPa and 72 MPa were obtained for AIN/W and AIN/Cu joints, respectively. Relationship between processing variables, joint strength and thickness of reaction layer was also explained.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2014년도 추계학술대회 논문집
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• pp.215-215
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• 2014

Composites layer of Al-Cr-Ni-O system was prepared on a steel plate by hydro-thermal process at $700^{\circ}C$ for 12 hours, which phase identification and thermal conductivity were determined. The composites layer consisted of aluminum nitride, alumina, chromium carbide and aluminium, which density was $3.7kg/m^3$. The thermal conductivity of the coating layer determined by thermal data acquisition system was about 98.0 W/m/ which depended on the AlN content. Numerical modelling of the heat transfer behavior of the coating layer was well agreement with the empirical data.

• 한국세라믹학회지
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• 제39권12호
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• pp.1177-1182
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• 2002

인산염 용액과의 반응으로 패각의 표면에 고 비표면적의 다공성 수산화아파타이트 층이 생성되는 거동을 정성적으로 관찰하였다. 수산화아파타이트의 생성기구는 패각 표면을 핵으로하는 용해-석출 반응으로 보이며 층의 생성은 다음의 과정에 의하였다. 1. 고상 표면 상의 고밀도 핵생성 및 성장 2. 결정의 접촉과 엉킴에 의한 미세 다공성 층의 형성 3. 층을 통한 용액의 확산과 내측으로의 층 두께의 성장

• 전자공학회논문지B
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• 제31B권8호
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• pp.211-218
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• 1994

In this paper we develope a hybrid learning rule to improve the robustness of multi-layer Perceptions. In most neural networks the activation of a neuron is deternined by a nonlinear transformation of the weighted sum of inputs to the neurons. Investigating the behaviour of activations of hidden layer neurons a new learning algorithm is developed for improved robustness for multi-layer Perceptrons. Unlike other methods which reduce the network complexity by putting restrictions on synaptic weights our method based on error-backpropagation increases the complexity of the underlying proplem by imposing it saturation requirement on hidden layer neurons. We also found that the additional gradient-descent term for the requirement corresponds to the Hebbian rule and our algorithm incorporates the Hebbian learning rule into the error back-propagation rule. Computer simulation demonstrates fast learning convergence as well as improved robustness for classification and hetero-association of patterns.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.937-939
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• 2009

In this paper, we report electrical properties of OTFTs made by ink-jet printing with polyvinylphenol (PVP) for bank layer and bis(triisopropylsilylenthynyl) pentacene (TIPS-pentacene) for semiconductor. We could achieve better crystallization and surface uniformity of TIPS pentacene by employing PVP bank layer. The OTFT with PVP bank layer exhibited an field-effect mobility of 0.18 $cm^2$/Vs, current on/off ratio of $2.09{\times}10^5$, and subthreshold slope of 0.42 V/decane.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권10호
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• pp.492-498
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• 2006

A novel surface plasmon resonance(SPR) multisensing method, which does not require imaging apparatus such as CCD, has been proposed and implemented experimentally. The proposed method is based on the multichannel SPR and the separation of signals by use of additional layers whose thickness is controlled. SPR signals are influenced by the thickness of sensing layer as well as the optical condition of sensing surface. As the SPR signals from different ligands are usually positioned closely, the reflected light from sensing surface does not provide us with the clear differences of resonance signal depending on the kinds of ligands. It was found from our experiments that SPR signals from each ligand that is located on the additional layer with different thickness can be separated clearly enough to identify various signals from different ligands. Proposed method with theoretical design and simulation has been verified experimentally by using $SiO_2$ thin film layer as additional layer.

• ETRI Journal
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• 제36권4호
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• pp.564-571
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• 2014

Sphere decoding (SD) for multiple-input and multiple-output systems is a well-recognized approach for achieving near-maximum likelihood performance with reduced complexity. SD is a tree search process, whereby a large number of nodes can be searched in an effort to find an estimation of a transmitted symbol vector. In this paper, a simple and generalized approach called layer pruning is proposed to achieve complexity reduction in SD. Pruning a layer from a search process reduces the total number of nodes in a sphere search. The symbols corresponding to the pruned layer are obtained by adopting a QRM-MLD receiver. Simulation results show that the proposed method reduces the number of nodes to be searched for decoding the transmitted symbols by maintaining negligible performance loss. The proposed technique reduces the complexity by 35% to 42% in the low and medium signal-to-noise ratio regime. To demonstrate the potential of our method, we compare the results with another well-known method - namely, probabilistic tree pruning SD.

• 센서학회지
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• 제22권5호
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• pp.374-378
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• 2013

In this paper, a new structure of probe unit is designed and fabricated with PDMS, which is well-known elastic material, as a buffer layer for increasing overdrive force and mechanical strength. In general, PDMS is widely used as actuation material due to its elasticity and compatibility of fabrication process. In this work, PDMS layer is chosen for mechanical elasticity of the proposed probe unit. We achieved the high overdrive force by placing PDMS buffer layer under the silicon based cantilever due to its elasticity. Moreover, the relation between prove length and overdrive force was measured by experiment in this work. Therefore, the various specifications of the micro prove unit can be designed by using the results of this work.