• Journal of Communications and Networks
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• v.13 no.4
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• pp.408-417
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• 2011

The stringent performance requirement for the high efficiency of routing protocols on the Internet can be satisfied by exploiting the threaded border gateway protocol (TBGP) on multi-cores, but the state-of-the-art TBGP performance is restricted by a mass of contentions when racing to access the routing table. To this end, the highly-efficient parallel access approach appears to be a promising solution to achieve ultra-high route processing speed. This study proposes a general routing table structure consisting of two-level tries for fast parallel access, and it presents a heuristic-based divide-and-recombine algorithm to solve a mass of contentions, thereby accelerating the parallel route updates of multi-threading and boosting the TBGP performance. As a projected TBGP, this study also modifies the table operations such as insert and lookup, and validates their correctness according to the behaviors of the traditional routing table. Our evaluations on a dual quad-core Xeon server show that the parallel access contentions decrease sharply by 92.5% versus the traditional routing table, and the maximal update time of a thread is reduced by 56.8 % on average with little overhead. The convergence time of update messages are improved by 49.7%.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.175-180
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• 2008

This paper is dedicated to the development of cooling devices such as mLHP with Fan-Fin system limited by noise and vibration. As we know, Heat pipe has the limitation of cooling capability to cool down the electronics. It is bounded by capillary and thermal limitation but heat load that it has to deal with is increasing. Especially Today's electronic technology has a tendency to integrate lots of function into the small piece of a processor like Dual core having 35W heat load for mobile and desktop computer respectively. There is an optimum operating condition of temperature, below $70^{\circ}C$, during the maximum heat load, 35W. There is the motivation needed to develop the new type of cooling devices and we can discuss about the new challenge beyond heat pipe.

• Journal of Magnetics
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• v.15 no.4
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• pp.204-208
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• 2010

Local wall thinning in pipelines affects the structural integrity of industries like nuclear power plants (NPPs). In the present study, a pulsed eddy current (PEC) differential probe with two excitation coils and two Hall-sensors was fabricated to measure the wall thinning in insulated pipelines. A stainless steel test sample was prepared with a thickness that varied from 1 mm to 5 mm and was laminated by plastic insulation to simulate the pipelines in NPPs. The excitation coils in the probe were driven by a rectangular current pulse, the difference of signals from two Hall-sensors was measured as the resultant PEC signal. The peak value of the detected signal is used to describe the wall thinning. The peak value increased as the thickness of the test sample increased. The results were measured at different insulation thicknesses on the sample. Results show that the differential PEC probe has the potential to detect wall thinning in an insulated NPP pipelines.

• Journal of IKEEE
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• v.16 no.4
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• pp.382-388
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• 2012

An H.264/AVC fast motion estimation methodology is presented in this paper. Advanced SIMD based NEON which is one of the parallel processing methods is supported under the ARM Cortex-A9 dual-core platform. NEON is applied to a full search technique with one of the various motion estimation methods and SAD operation count of each macroblock is reduced to 1/4. Pixel values of the corresponding macroblock are assigned to eight 16-bit NEON registers and Intrinsic function in NEON architecture carried out 128 bits arithmetic operations at the same time. In this way, the exact motion vector with the minimum SAD value among the calculated SAD values can be designated. Experimental results show that performance gets improved 30% above average in accordance with the size of image and macroblock.

• The Transactions of the Korean Institute of Power Electronics
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• v.15 no.4
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• pp.274-281
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• 2010

This paper proposes a DFPS (Dual Frequency Power Source) impedance matching device for uniformity improvement of a semiconductor plasma etching system. The DFPS consists of two parts for safe plasma processing on large-area substrates. The first part is an ICP (Inductively Coupled Plasma) for high integration by using ferrite core. The second part is a CCP (Capacitive Coupled Plasma) to control uniformity of whole cells. Proposed DFPS can achieve high productivity improvement required for semiconductor equipment industry. The proposed plasma system is analyzed, simulated and experimentally verified with a matching equipment at 27.12MHz and 400kHz.

• Proceedings of the KIPE Conference
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• 2015.11a
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• pp.159-160
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• 2015

최근 초기 투자비용은 큰 반면 에너지 이용률은 낮은 UPS(Uninterruptible power supply)를 ESS(Energy storage system)로서 활용하는 하이브리드 ESS에 대한 관심이 커지고 있다. 하이브리드ESS는 비상시 중요부하에 공급할 최소 전력을 제외한 전력을 수요관리로 활용함으로써 UPS에 저장되어 있는 에너지를 비상전원 기능과 수요관리 기능으로 폭넓게 사용할 수 있는 시스템이다. 이 시스템을 구성하는 3개의 PCS를 통합 제어하기 위해 채택한 듀얼코어 기반의 고성능 MCU TMS320F28377D를 이용하면 많은 PWM, ADC포트는 물론 충분한 연산시간 확보가 가능하다. 본 논문에서는 제안하는 하이브리드 ESS의 구성에 대해 소개하고 사용된 제어기의 구조, 각 PCS들을 통합 제어하기 위해 사용한 듀얼코어 기반의 DSP TMS320F28377D에 대해 설명하고자 한다.

• Journal of Power Electronics
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• v.17 no.4
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• pp.1027-1036
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• 2017

The brushless doubly-fed induction generator (BDFIG) is a new type of dual stator winding induction generator. In such a generator, both the power winding (PW) and the control winding (CW) are housed in the stator. This paper presents the performance characteristics of a stand-alone BDFIG operation system. A new T-type steady-state model of a BDFIG is proposed. This model is more suitable for the performance analysis of stand-alone BDFIGs than the conventional Π-type steady-state model and the simplified inner core steady-state model. The characteristics of the power flow and CW current are analyzed by detailed mathematical derivations on the basis of the proposed T-type steady-state model. The analysis results are verified by experiments, which are carried out on a prototype BDFIG. The results of the performance analysis contribute to simplifying the control circuit, improving the control performance, and selecting an appropriate BDFIG for actual industrial applications.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.227-229
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• 2016

Drone is demanding more than detaile hardware and software systems because Drone have characteristic flying. If Drone is a plane crash. they have risk of personal injury and property damage. now Drone control core system is preventing a plane crash and flight unsafe flying. The key is to help flying to convert for various external environment. This research prevent a plane crash that system planning to treat six-senser-figure doubly is IMU trouble or a trouble caused by a passing parameters and IMU install to help stability in flying.

• Human Ecology Research
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• v.62 no.2
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• pp.197-216
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• 2024

The dual aims of this study were i) to explore the effectiveness of an assessment method that can measure the competencies learned through high school home economics and ii) develop a competency-based assessment framework for high school home economics, including components of competency-based assessment, item development system, and other elements. The study involved the following stages: literature analysis, draft development, concretization, validity verification, and final version. Based on the results of the literature analysis and expert deliberation, a competency-based assessment framework for high school home economics was developed which comprised three dimensions: 'core idea' × 'process' × 'context and value'. Based on this, an item analysis table was presented to systematize various activities for the competency-based assessment of high school home economics, following which a holistic rubric suitable for competency assessment tasks was proposed by referring to the newly developed 'process' dimension assessment criteria. This study is significant in that it is the first to propose a competency-based assessment framework that systematically presents a variety of assessment activities. These will facilitate the development of assessment standards and tools that teachers can refer to or trust in the changing school environment due to the introduction of the standard-based assessment system based on a high school credit system, and the guarantee of a minimum achievement level.

• Restorative Dentistry and Endodontics
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• v.32 no.5
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• pp.445-458
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• 2007

The purpose of this study was to evaluate the bond strength of a new Single step system with different curing mode composites, and to evaluate the effect of the intermediate resins which have different hydrophilicity on bonding ability by means of the micro shear bond testing and TEM examination for the adhesive interface. The adhesive used in this study was an experimental single step system (Bisco Inc., Schaumburg IL). Experimental groups were produced by using six kinds of intermediate resin having different hydrophilicity that was hydrophilic, hydrophobic and most hydrophobic resin and as filled or not after applying adhesive. Each experimental group was further divided into two subgroups whether the adhesive was light cured or not. Dual cured composite (Bis Core, Bisco Ltd., Schaumburg, IL) was placed on the adhesive layer as light cure or self cure mode. The results or bond strength were statistically analyzed using one way ANOVA and multiple comparisons are made using Tukey's test at ${\alpha}\;<\;0.05$ level. The results of this study were as follows ; 1. The application of intermediate resin did not increase the bond strength for light cured composite. 2. The bond strength of an experimental adhesive with self cured composite was significantly increased by the application of intermediate resin layer. 3. The bond strength of adhesive was irrespective of the cure or not of itself before intermediate resin layer applied. 4. As applied hydrophilic resin layer was, the initial bond strength was higher than both hydrophobic and most hydrophobic one used but there was no significance. Using a single step adhesive with dual/self cured composite, the incompatibility between both of them should be solved by the application of intermediate hydrophobic resin to reduce the adhesive permeability. However, Single step adhesive can be used in the light cured composite restoration without any decrease of the initial bond strength.