• Journal of Electrical Engineering and Technology
• /
• 제4권2호
• /
• pp.159-167
• /
• 2009

This paper presents the Improved Pre-prepared Power Demand (IPPD) table and Muller's method as a means of solving the Profit Based Unit Commitment (PBUC) problem. In a deregulated environment, generation companies (GENCOs) schedule their generators to maximize profits rather than to satisfy power demand. The PBUC problem is solved by the proposed approach in two stages. Initially, information concerning committed units is obtained by the IPPD table and then the subprob-lem of Economic Dispatch (ED) is solved using Muller's method. The proposed approach has been tested on a power system with 3 and 10 generating units. Simulation results of the proposed approach have been compared with existing methods and also with traditional unit commitment. It is observed from the simulation results that the proposed algorithm provides maximum profit with less computational time compared to existing methods.

• Journal of Electrical Engineering and Technology
• /
• 제13권4호
• /
• pp.1644-1654
• /
• 2018

Eigenvalue distributions for a periodic metal-insulator-metal waveguide, classified into the point spectrum and the discretized continuous spectrum (DCS), are investigated as functions of frequencies, gap widths, and periods. Muller's method is suggested for solving exact eigenvalues, and we propose the scheme for finding proper initial values in the Muller's method by considering only ${\Re}e({\varepsilon}_r)$ in the dispersion equation. We then find that anti-crossing behavior, repulsive effect between the point spectrum and the DCS, becomes stronger when the real parts of the roots in the point spectrum have smaller values. Finally, we examine the transmittances of a single subwavelength slit for real metals using the mode matching technique. The transmittances in real metals similarly follow those of the perfect electric conductor (PEC) at low frequencies, while the patterns at higher frequencies begin to differ from the PEC.

• ETRI Journal
• /
• 제21권1호
• /
• pp.28-39
• /
• 1999

Koblitz has suggested to use "anomalous" elliptic curves defined over ${\mathbb{F}}_2$, which are non-supersingular and allow or efficient multiplication of a point by and integer, For these curves, Meier and Staffelbach gave a method to find a polynomial of the Frobenius map corresponding to a given multiplier. Muller generalized their method to arbitrary non-supersingular elliptic curves defined over a small field of characteristic 2. in this paper, we propose an algorithm to speed up scalar multiplication on an elliptic curve defined over a small field. The proposed algorithm uses the same field. The proposed algorithm uses the same technique as Muller's to get an expansion by the Frobenius map, but its expansion length is half of Muller's due to the reduction step (Algorithm 1). Also, it uses a more efficient algorithm (Algorithm 3) to perform multiplication using the Frobenius expansion. Consequently, the proposed algorithm is two times faster than Muller's. Moreover, it can be applied to an elliptic curve defined over a finite field with odd characteristic and does not require any precomputation or additional memory.

• 한국방사선학회논문지
• /
• 제12권1호
• /
• pp.31-37
• /
• 2018

단창형의 Geiger-Muller 계수관을 이용한 표면오염검사에서 베타선을 측정하기 위해 외부로 노출된 디텍터를 보호하는 방법으로 랩을 사용하고 있는데 이 방법이 측정계수율과 교정인자에 미치는 영향을 분석하고 방사선작업종사자에게 과도한 랩의 사용은 베타선의 측정값에 영향을 줄 수 있음을 인지시켜주고자 하였다. 실험방법은 3 KBq, 1.5 KBq, 0.3 KBq의 에너지가 다른 베타선을 이용하여 랩 두께에 따른 베타선 측정계수율과 교정인자의 변화를 비교 분석하였다. 실험 대상으로는 2012년 3월 한국인정기구 (KOLAS) 인증을 받은 교정센터에서 보유한 단창형의 Geiger-Muller 계수관을 대상으로 하였으며, Cl-36(Chlorine)과 Sr-90(Strontium)을 베타선 방사선원으로 사용하였다. 측정계수율은 랩 두께가 증가할수록 감소함을 확인 할 수 있었고 교정인자는 랩 두께가 증가할수록 증가하는 것을 알 수 있었다. 측정계수율의 감소와 교정인자의 변화는 기기지시값의 정확도를 감소시킬 수 있지만 디텍터의 오염 및 손상 또한 베타선 측정에서 중요한 영향을 주기 때문에 어느 정도 두께의 랩을 사용함이 가장 효과적인지 알아볼 필요성이 있다. 측정계수율과 교정인자의 낮은 변화율을 보여주는 두께의 랩을 사용한다면 디텍터를 보호하면서 베타선의 측정값에도 영향을 최소한으로 줄 수 있을 것으로 사료된다.

• 정보보호학회논문지
• /
• 제12권5호
• /
• pp.45-51
• /
• 2002

Koblitz 타원곡선과 같이 표수(characteristic)가 2인 작은 유한체 위에서 정의된 non-supersingular 타원곡선은 스칼라 곱을 효율적으로 구현하기 위하여 프로베니우스 자기준동형 (Frobenius endomorphism)이 유용하게 사용된다. 본 논문은 확장된 프로베니우스 함수를 사용하여 스칼라 곱의 고속연산을 가능하게 하는 방법을 소개한다. 이 방법은 Muller［5］가 제안한 블록방법(block method) 보다 선행계산을 위해 사용되는 덧셈량을 줄이는 반면에 확장길이는 거의 같게 하므로 M(equation omitted )ller의 방법보다 효율적이다.

• 한국소음진동공학회논문집
• /
• 제17권2호
• /
• pp.121-129
• /
• 2007

There has been much effort to find suitable methods for structural analysis in the mid-frequency region where traditional low frequency methods have increasing uncertainties whilst statistical energy analysis is not strictly applicable. Systems consisting of relatively stiff beams coupled to flexible plates have a particularly broad mid-frequency region where the beams support only a few modes whilst the plate has a high modal density and modal overlap. A system of two parallel beams coupled to a plate is investigated based on the wave method, which is an approximate method. Muller's method is utilised for obtaining complex roots of a dispersion wave equation, which does not converge in the conventional wave method based on a simple iteration. The wave model is extended from a single-beam-plate system, to a plate with two identical beams which is modelled using a symmetric-antisymmetric technique. The important hypothesis that the coupled beam wavenumber is sufficiently smaller than the plate free wavenumber is experimentally verified. Finally, experimental results such as powers and energy ratios show the validity of the analytical wave models.

• Archives of Plastic Surgery
• /
• 제41권1호
• /
• pp.71-76
• /
• 2014

Background Numerous methods exist for simultaneous correction of mild blepharoptosis during double eyelid surgery. These methods are generally categorized into either incisional (open) or non-incisional (suture) methods. The incisional method is commonly used for the creation of the double eyelid crease in patients with excessive or thick skin. However, concurrent open ptosis correction is often marred by the lengthy period of intraoperative adjustment, causing more swelling, a longer recovery time, and an increased risk of postoperative complications. Methods The authors have devised a new, minimally invasive technique to alleviate mild ptosis during incisional double eyelid surgery. The anterior lamella is approached through the incisional technique for the creation of a double eyelid while the posterior lamella, including Muller's and levator muscles, is approached with the suture method for Muller's plication and ptosis correction. Results The procedure described was utilized in 28 patients from June 2012 to August 2012. Postoperative asymmetry was noted in one patient who had severe preoperative conjunctival scarring. Otherwise, ptosis was corrected as planned in the rest of the cases and all of the patients were satisfied with their postoperative appearance and experienced no complications. Conclusions Our hybrid technique combines the benefits of both the incisional and suture methods, allowing for a predictable and easily reproducible correction of blepharoptosis with an aesthetically pleasing double eyelid.

• 한국통신학회논문지
• /
• 제30권9C호
• /
• pp.860-870
• /
• 2005

본 논문에서는 karnaugh map(k-map)상의 셀을 이용하여 $2^{n}$개의 서로 다른 극수(polarity)를 갖는 GRM(Generalized Reed-Muller)상수를 생성하는 새로운 기법을 제안하였다. n개의 입력변수에 대한 일반적인 GRM 함수의 생성 방법은 단일 변수에 대한 변환 행렬을 구하고 이를 n번의 Kronecker 곱을 행한 변환 행렬을 이용하여 GRM 상수를 구하는 것이다. 이런 방법을 사용하는 경우, 변수의 숫자가 증가함에 따라 변환 행렬의 차수가 $2^{n}\times2^{n}$로 커지는 단점을 갖는다. 이에 반하여 본 논문에서는 k-map상에서 변수를 축약시킨 셀 [$f_{i}$]을 구하고 이를 단일 변수 변환 행렬과 연산하여 GBM 상수를 구하는 새로운 기법을 제안한다. 본 논문에서 제안한 새로운 방법과 타 논문과의 비교를 한 결과, 기존 방법은 가산기, 승산기, KP(Kronecker 곱 승산기)회로가 필요한데 반하여 본 논문에서는 가산기만이 필요하므로 효율적인 VLSI 설계에 유리하다

• KIEE International Transactions on Electrophysics and Applications
• /
• 제3C권5호
• /
• pp.199-206
• /
• 2003

Numerical solutions to complex characteristic equations are quite often required to solve electromagnetic wave problems. In general, two traditional complex root search algorithms, the Newton-Raphson method and the Muller method, are used to produce such solutions. However, when utilizing these two methods, the choice of the initial iteration value is very sensitive, otherwise, the iteration can fail to converge into a solution. Thus, as an alternative approach, where the selection of the initial iteration value is more relaxed and the computation speed is high, Davidenko's method is used to determine accurate complex propagation constants for leaky circular symmetric modes in circular dielectric rod waveguides. Based on a precise determination of the complex propagation constants, the leaky mode characteristics of several lower-order circular symmetric modes are then numerically analyzed. In addition, no modification of the characteristic equation is required for the application of Davidenko's method.

• Archives of Pharmacal Research
• /
• 제27권11호
• /
• pp.1114-1119
• /
• 2004

This paper describes the quantitative determination of flavonoids, tannins and ellagic acid in the leaves from wild and cultivated variations of Rubus L. species (Rosaceae): raspberry (2 wild and 13 cultivars) and blackberry (3 wild and 3 cultivars). The content of flavonoids was analyzed using spectrophotometric (the Christ-M llers method) and HPLC analysis after acid hydrolysis. The content of tannins was determined by the weight method, with hide powder, described by German Pharmacopoeia 10 (DAB 10). Ellagic acid content was examined using the HPLC method after acid hydrolysis. Flavonoid content, determined using the Christ-Muller's method was higher for the blackberry leaves than for the raspberry leaves and varied between 0.46% and 1.05%. Quercetin and kaempferol were predominant in all samples analyzed using the HPLC method. The highest flavonoid content was found in the leaves of R. nessensis (1.06%); with results in all of the examined samples varying between 0.27% and 1.06%. The concentration of ellagic acid in all species was determined after acid hydrolysis and ranged from 2.06% to 6.89%. The leaves of raspberries are characterized by greater amounts of tannins (varying between 2.62% and 6.87%) than the leaves of other species. The results from this study indicate that the analyzed species are a rich source of flavonoids, ellagic acid and tannins, which may be used for the quality assessment of Rubus L. species leaves.