• ETRI Journal
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• 제26권6호
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• pp.555-559
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• 2004

We propose an efficient digital IF down converter architecture for dual-mode WCDMA/cdma2000 based on the concept of software defined radio. Multi-rate digital filters and fractional frequency conversion techniques are adopted to implement the front end of a dual-mode receiver for WCDMA and cdma2000. A sub-sampled digital IF stage was proposed to support both WCDMA and cdma2000 while lowering the sampling frequency. Use of a CIC filter and ISOP filter combined with proper arrangement of multi-rate filters and common filter blocks resulted in optimized hardware implementation of the front end block in 292k logic gates.

• 대한수학회보
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• 제46권3호
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• pp.521-534
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• 2009

In this paper we present new large-update primal-dual interior point algorithms for $P_*$ linear complementarity problems(LAPS) based on a class of kernel functions, ${\psi}(t)={\frac{t^{p+1}-1}{p+1}}+{\frac{1}{\sigma}}(e^{{\sigma}(1-t)}-1)$, p $\in$ [0, 1], ${\sigma}{\geq}1$. It is the first to use this class of kernel functions in the complexity analysis of interior point method(IPM) for $P_*$ LAPS. We showed that if a strictly feasible starting point is available, then new large-update primal-dual interior point algorithms for $P_*$ LAPS have $O((1+2+\kappa)n^{{\frac{1}{p+1}}}lognlog{\frac{n}{\varepsilon}})$ complexity bound. When p = 1, we have $O((1+2\kappa)\sqrt{n}lognlog\frac{n}{\varepsilon})$ complexity which is so far the best known complexity for large-update methods.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.673-676
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• 2002

Real time communication is very important in factory automation system using FieldBus. In this paper, we Propose the method to drive dual motors with one controller using CAN In traditional induction motor control technique, two independent Inverters are used to drive dual motors independently. In this case, two controllers are needed. Our proposed dual motors control scheme which use only one microprocessor has many advantages in the view of economic and performance compared to conventional technique.

• Communications for Statistical Applications and Methods
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• 제22권2호
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• pp.137-146
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• 2015

Singh (2013) considered the dual problem to the calibration of design weights to obtain a new generalized linear regression estimator (GREG) for the finite population total. In this work, we have made an attempt to suggest a way to use the dual calibration of the design weights in case of multi-auxiliary variables; in other words, we have made an attempt to give an answer to the concern in Remark 2 of Singh (2013) work. The same idea is also used to generalize the GREG estimator proposed by Deville and S$\ddot{a}$rndal (1992). It is not an easy task to find the optimum values of the parameters appear in our approach; therefore, few suggestions are mentioned to select values for such parameters based on a random sample. Based on real data set and under simple random sampling without replacement design, our approach is compared with other approaches mentioned in this paper and for different sample sizes. Simulation results show that all estimators have negligible relative bias, and the multivariate case of Singh (2013) estimator is more efficient than other estimators.

• 한국세라믹학회지
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• 제48권5호
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• pp.390-395
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• 2011

The objective of our study was to produce an imitation bone material consisting of hydroxyapatite with a compact and spongy structure. This study shows the ideal content of $SiO_2$ and the sintering temperature to produce imitation bone that has the mechanical properties of natural bone. On the basis of our determination of the ideal conditions, a compact part was produced and its mechanical properties were tested. A compact part made of 0.5 wt% $SiO_2$ and sintered at $1350^{\circ}C$ showed excellent mechanical properties. The bioactivity of the compact part under this condition was tested, and it was found to be bioactive. The porous part was produced by controlling the powder size, and the dual structure was manufactured by combining the compact and porous parts. A water permeability test confirmed that the dual structure had an interconnected pore structure. Therefore, this dual-body structure is feasible for use in the creation of implants.

• Journal of Power Electronics
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• 제2권4호
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• pp.312-324
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• 2002

This paper presents a new PWM DC/DC converter with dual output power using single power stage, which has the isolation characteristics between each dual output. The proposed converter topology consists of two switches ($S_B$ and $S_F$) and only single secondary winding. Therefore, the proposed converter has better advantages of not only low cost and small size but also high power density because of using minimum components and devices compared with conventional methods which use multi winding transformers or several converters. The operating principle of the proposed converter topology, which includes the conventional auxiliary ZVT (Zero-Voltage-Transition) circuit to implement soft switching of the main switch, is illustrated in detail and the validity of the proposed converter is verified through several simulated and experimental results.

• Transactions on Electrical and Electronic Materials
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• 제15권1호
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• pp.20-23
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• 2014

Dual phase steels have a microstructure comprising of a polygonal ferrite matrix together with dispersed islands of martensite. There are clear differences between the image quality (IQ) map of the dual phase and the corresponding ferritic/pearlitic structures, both in the as-heat treated and cold rolled conditions. Electron backscatter diffraction (EBSD) techniques were used to study the evolution substructure of steel due to plastic deformation. The martensite-ferrite and ferrite-pearlite interfaces were observed. The interface can be a source of mobile dislocations which the bands seem to originate from the martensite islands. In particular, the use of image quality is highlighted.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 전력전자학술대회 논문집
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• pp.530-533
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• 2001

Interleaved Dual Boost(IDB) converter can reduce current ripple, switching loss and harmonics without filter in input power line. Moreover, this improve power factor. In this paper, we will use the state average methode and small signal analysis at the Interleaved dual boost converter. 4-type controllers were designed by using control transfer function. The result of these controller simulations is analyzed and proposed a proper controller at IDB

• Hip & pelvis
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• 제35권4호
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• pp.277-280
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• 2023

Dislocation after a total hip arthroplasty occurs in approximately 1% of patients; however, the frequency is much higher after revision surgery. To prevent dislocation, use of a larger femoral head is recommended, and a dual mobility femoral head has been introduced. However, reducing the dual mobility femoral head to the acetabular component is difficult in cases involving contracture in the soft tissue around the joint. A 72-year-old male patient who developed a periprosthetic joint infection underwent two-stage revision surgery using MUTARS^®. Two months after the revision, the hip joint became dislocated and manual reduction was attempted; however, dislocation occurred again. During another revision using a dual mobility bearing, the soft tissue around the hip joint was too tight to reduce. The problem was overcome by first repositioning the dual mobility head into the acetabular socket, followed by assembly of the diaphyseal portion of the implant.

• 한국방사선학회논문지
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• 제17권6호
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• pp.809-817
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• 2023

뇌출혈 진단 방법 중 CT는 비침습적으로 피사체의 3차원 영상을 제공할 수 있다. 그래서 응급실에서 급성인 환자 상대로 많이 사용되고 중요한 역할을 담당하고 있다. 뇌혈관 CT는 다른 혈관 CT에 비해 비교적 촬영 빈도가 높으며 뇌혈관 CT 검사 시 적절한 SNR, 합리적인 유효선량으로 검사를 해야한다. 뇌혈관 CT 검사 시 이중에너지와 단일에너지를 이용하였을 때 실질적으로 어느 것이 유효선량이 적으며, SNR이 차이가 없는지 환자영상과 Phantom영상을 같이 비교하였다. SNR과 CNR의 P값이 0.05이상일 때 통계적으로 차이가 없다고 보았고, 유효선량은 0.05미만일 경우 통계적으로 차이가 있다고 보았다. 실험에서는 병원영상의 환자선량을 비교하였을 때 이중에너지의 유효선량이 53.53% 적게, Phantom의 OLSD 이중에너지 유효선량이 57.94% 적게, Phantom의 Dose Report의 이중에너지 유효선량이 56.04% 적었다. 그래서 뇌혈관조영 CT는 이중에너지를 권장한다.