• 충청수학회지
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• 제22권3호
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• pp.467-480
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• 2009

In 1859, Bernhard Riemann, in his epoch-making memoir, extended the Euler zeta function $\zeta$(s) (s > 1; $s{\in}\mathbb{R}$) to the Riemann zeta function $\zeta$(s) ($\Re$(s) > 1; $s{\in}\mathbb{C}$) to investigate the pattern of the primes. Sine the time of Euler and then Riemann, the Riemann zeta function $\zeta$(s) has involved and appeared in a variety of mathematical research subjects as well as the function itself has been being broadly and deeply researched. Among those things, we choose to make a further investigation of the following subjects: Evaluation of $\zeta$(2k) ($k {\in}\mathbb{N}$); Approximate functional equations for $\zeta$(s); Series involving the Riemann zeta function.

• 대한수학회논문집
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• 제35권4호
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• pp.1193-1202
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• 2020

We consider the integral ${{\int}_{0}^{\infty}}(\frac{sin\;x}{x})^n\;dx$ as a function of the positive integer n. We show that there exists an asymptotic series in ${\frac{1}{n}}$ and compute the first terms of this series together with an explicit error bound.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.401-403
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• 2011

• 대한수학회논문집
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• 제36권3호
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• pp.485-494
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• 2021

In this article, we prove the existence of a solution to some classes of integral equations of generalized convolution type generated by the Kontorovich-Lebedev (K) transform, the Laplace (𝓛) transform and the Fourier (F) transform in some appropriate function spaces and represent it in a closed form.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.157.6-157
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• 2001

We estimated various neuron functions to construct of engineering neurons, which are the combination of sigmoid, linear, sine, quadric, double/single bended, soft max/minimum functions. These combinations are estimated by the property on the potential surface between the learning points, calculation speed, and learning convergence; because the surface depends on the inference ability of a neuron system; and speed and convergence are depend on the efficiency on the points of engineering applications. After the evaluating discussions, we can select more appropriate combination than original sigmoid function´s, which is single bended function and linear one. The combination ...

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.763-766
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• 2002

This paper proposes design of new linear bipolar OTAs composed of an hyperbolic function circuit and a triple-tail cell. Two types of the OTAs are presented; one employs a hyperbolic sine circuit and the other contains a hyperbolic cosine circuit. The linear input voltage ranges of the proposed OTAs are wider than that of the conventional triple-tail cell, though the power dissipation is smaller. The results of SPICE simulation show that satisfactory characteristics are obtained.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제17권4호
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• pp.397-411
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• 2010

In this paper, we will investigate the superstability for the sine functional equation from the following Pexider type functional equation: $f(x+y)-g(x-y)={\lambda}{\cdot}h(x)k(y)$ ${\lambda}$: constant, which can be considered an exponential type functional equation, the mixed functional equation of the trigonometric function, the mixed functional equation of the hyperbolic function, and the Jensen type equation.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.473-478
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• 2003

To detect motions of bodies, we have discussed them with two viewpoints; one is a detection algorithm, and another is the hardware implementation. The former is to find small terms expansions for sine/cosine functions. We researched Maclaurin and optimum expansions, and moreover to reduce hardware amounts, revised the expansions. The expansions don't include divide calculations, and the error is within 0.01%. As for the former problem, there is another approach also; that is the cordic method. The method is based on the rotation of a vector on the complex plain. It is simple iterations and don't require large logic. We examined the precision and convergence of the method on C-simulations, and implemented on HDL. The later problem is to make FPGA within small gates. We considered approaches to eliminate a divider and to reduce the bit number of arithmetic. We researched Newton-Raphson's method to get reciprocal numbers. The higher-order expression shows rapid convergence and doesn't be affected by the initial guess. It is an excellent algorithm. Using them, we wish to design a detector, and are developing it on a FPGA.

• 한국통신학회논문지
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• 제34권7C호
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• pp.724-729
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• 2009

Binary offset carrier (BOC) 신호의 동기화 과정은 일반적으로 수신된 BOC 신호와 단말기에서 생성된 BOC 신호의 상관값을 이용히여 이루어진다. 따라서 BOC 신호의 자기상관힘수에 존재하는 다수의 주변 첨두는 BOC 신호의 동기화 오차 발생에 있어 주요한 원인이 된다. 이러한 문제를 해결하기 위하여 본 저자들은 최근 sine 위상 및 cosine 위상 BOC 신호 각각에 대하여 주변 첨두가 완벽히 제거된 새로운 상관힘수들을 제안하였다 [3]. 본 논문에서는 차세대 global navigation satellite systems의 (GNSS) 변조 기법으로 주목받고 있는 composite BOC (CBOC) 신호의 동기화를 위하여 기존 연구와 유사한 접근을 통해 주변 첨두가 완벽히 제거된 새로운 CBOC 상관힘수를 제안한다.

• 방송공학회논문지
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• 제9권4호
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• pp.384-390
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• 2004

본 논문에서는 44.1KHz에서 48KHz로 표본화 주파수를 변환하는 알고리듬들의 성능을 비교한다. 비교 한 기법은 다위상 구조로 구현된 기본적인 기법, sinc 함수를 이용한 기법, 다위상 구조의 다단계 구현 기법, 그리고 B-spline을 이용한 기법 등이다. 먼저, 공정한 비교를 위해 이 4가지 기법을 이용한 표본화율 변환기들을 고품질 조건하에 재설계하고, 이들의 H/W 복잡도를 메모리 요구량과 계산량 측면에서 비교하였다. 그 결과, 메모리 요구량 측면에서는 B-spline을 이용한 기법이 가장 우수하였지만, 계산량 측면에서는 기본적인 기법과 sinc 함수를 이용한 기법이 가장 우수함을 확인할 수 있었다.