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Cocan, Moise;Pop, Bogdana
- Journal of applied mathematics & informatics
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- v.6 no.1
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- pp.79-88
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- 1999
This work aims to establish an algorithm for solving the problem of convex programming with several objective-functions with linear constraints. Starting from the idea of Rosen's algorithm for solving the problem of convex programming with linear con-straints and taking into account the solution concept from multi-dimensional programming represented by a program which reaches "the best compromise" we are extending this method in the case of multidimensional programming. The concept of direction of min-imization is introduced and a necessary and sufficient condition is given for a s∈Rn direction to be a direction is min-imal. The two numerical examples presented at the end validate the algorithm.

Kim, Y.H.;Kim, D.K.
- Journal of the Korean Society for Heat Treatment
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- v.11 no.4
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- pp.258-267
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- 1998
For the purpose of investigating the growth characteristics and composition of nitrides, gas nitridings of the austenitic stainless steel, STR 36 heat resisting steel and martensitic stainless steel are investigated at the temperature ranges between $500^{\circ}C$ and $675^{\circ}C$ for 5hours under the $75%NH_3+5%CO_2+20%$Air gas atmosphere. When gas nitriding the austentic stainless steel and STR 36 heat resisting alloy, the abnormal growth behavior of compound layer deviating from the conventional diffusion law with increasing temperature appears, while the compound layer of martensitic stainless steel shows the normal diffusional growth behavior. From the examination of microstructure, X-ray diffraction and hardness test, it is concluded that the abnormal growth behavior of compound layer with increasing temperature induces from the formation and dissolution of CrN and ${\gamma}^{\prime}-Fe_4N$ at the nitriding temperature ranges of $600{\sim}650^{\circ}C$.
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서혜숙;한상범;이근호;황종선
- Proceedings of the Korean Information Science Society Conference
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- 2003.10c
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- pp.319-321
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- 2003
모바일 컴퓨팅 환경은 크게 모바일 노드, 무선망, 그리고 이동성이라는 기술로 이루어진다. 이음새없는 (seamless) 이동성을 제공하기 위한 기존의 Shadow Registration 방법은 핸드오프가 발생하기 이전에 이웃한 모든 노드들(AAAF/sbu n/)에게 모바일 노드의 관련 정보를 사전등록(Shadow Registration)하는 방법을 제안하여 핸드오프 이후에 발생하는 끊김이나 지연을 방지하였다. 그러나 이러한 Shadow Registration의 경우 백본 네트워크에 불필요한 트래픽 발생 및 데이터 관리라는 문제를 야기시킨다. 본 논문은 이러한 문제점들을 개선하고자 새롭게 사전등록 트리거 영역(STR: Shadow Trigger Region)을 설정하고, STR 내에 모바일 노드(MN)가 위치할 경우 MN의 이동 방향을 이용하여 최소한의 사전등록영역(SRR: Shadow Registration Region)을 찾아내는 방법을 제안한다. 결과적으로 제안된 SRR 은 최대 2 개의 이웃노드(AAAF$_2$)에게만 사전등록을 요청하면 되므로, 기존의 방법에 비해 최대 ∑(n2)번의 사전등록 횟수를 줄이면서 끊김과 지연도 방지할 수 있는 효과적인 방법이다.
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Hwang, Sung-Hyun;Park, Hyun-Cheol k;Park, Hyung-Jin
- Proceedings of the IEEK Conference
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- 2002.07c
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- pp.1819-1822
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- 2002
The authors propose a robust symbol timing recovery (STR) for telephone line modems supporting data rates up to 32 Mbps. The STR is initialized by a start signal from carrier sensor, and the novel method is proposed which resolves the difference between the frequency of the transmitter's clock and the receiver's clock, called baud frequency offset. The proposed method is applied on digital receiver in a 16 frequency diverse quadrature amplitude modulation (FDQAM) system.
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Kim, Gwon-Sub;Lee, Oh-Keol;Kim, Sang-Hyo;Ko, Tai-Eun
- Proceedings of the KIEE Conference
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- 1996.07b
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- pp.1113-1115
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- 1996
The servo system requires faster and more accurate dynamic responses. A new technique for the position control of DC servo motors is presented in this paper. The proposed technique employs a Self Tuning Regulator Proportional Integral Derivative(STR PID) position control systems in order to improve the dynamic performance of a DC servo motor. Recursive -least -squares (RLS) method is used in order to estimate the STR PID coefficients, $K_P$, $K_I$, and $K_D$. In order to consider dynamics such as voltage, angular velocity, and rotor angle, the above method was applied position control system.
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