• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1990년도 봄 학술발표회 논문집
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• pp.108-115
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• 1990

This paper contains experimental studies on the flexural cracking behabior of PPC one-way slabs. Three post tensioned bonded PPC slabs with the same prestressing ratio and ultimate moment strength were tested. Based upon test results, this paper also presents the crack width prediction formula PPC slab. According to the crack theory developed mainly in Europe, crack width formula is given as the product of crack spacing and mean steel strain after decompression. Aaaaverage crack spacing formula is composed of many factors mainly such as concrete cover, concrete effective area in tension, sum of reinforcing bars perimeters and mixed reinforcements. In particular, it is very important to specify the bond characteristics of mixed reinforcements, since bond characteristics of PC bars are different from those of non-tensioned deformed bars. For this reason, a reduced bond coefficients for PS bars is employed in this study.

• Management Science and Financial Engineering
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• 제12권1호
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• pp.95-112
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• 2006

Disassembly scheduling is the problem of determining the quantity and timing of disassembling used or end-of-life products while satisfying the demand of their parts and/or components over a planning horizon. The case of assembly product structure is considered while the resource capacity constraints are explicitly considered. A cost-based objective is considered that minimizes the sum of disassembly operation and inventory holding costs. The problem is formulated as an integer programming model, and a two-stage heuristic with construction and improvement algorithms is suggested in this paper. To test the performance of the heuristic, computational experiments are done on randomly generated problems, and the results show that the heuristic gives near optimal solutions within a very short amount of computation time.

• 대한산업공학회지
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• 제36권4호
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• pp.243-247
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• 2010

Every products, which made by mass production, is not identical in their size but have variations in some intervals specified by tolerance dimensions. Tolerances play major role in standardization of part and its quality, and also make a huge impact on manufacturing cost. The optimal condition for tolerances is giving the values as loose as possible for low production cost while satisfying quality specification, which usually demand tight control of tolerances. Tolerance analysis is necessary to get an optimal solution for this conflict situation. This paper have studied tolerance analysis for universal joint assembly of vehicle steering system and tried to find useful results of the study for product design and quality control.

• 대한수학회논문집
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• 제35권3호
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• pp.891-906
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• 2020

In this paper, the commutative module amenable Banach algebras are characterized. The hereditary and permanence properties of module amenability and the relations between module amenability of a Banach algebra and its ideals are explored. Analogous to the classical case of amenability, it is shown that the projective tensor product and direct sum of module amenable Banach algebras are again module amenable. By an application of Ryll-Nardzewski fixed point theorem, it is shown that for an inverse semigroup S, every module derivation of 𝑙¹(S) into a reflexive module is inner.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2006년도 추계학술대회
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• pp.327-331
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• 2006

This paper considers an integrated inventory-distribution system with a fleet of heterogeneous vehicles employed where a single warehouse distributes a single type of products to many spatially distributed retailers to satisfy their dynamic demands and the product is provided to the warehouse via procurement ordering from any manufacturing plant or market The Problem is formulated as an Mixed Integer Programming with the objective function of minimizing the sum of inventory holding cost (at the warehouse and retailers), and transportation cost and procurement ordering cost at the warehouse, subject to inventory-balancing constraints, ordering constraints, vehicle capacity constraints and transportation time constraints. The problem is Proven to be NP-hard. Accordingly, a Lagrangean heuristic procedure is derived and tested for its effectiveness through computational experiments with some numerical instances.

• 대한수학회보
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• 제50권4호
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• pp.1389-1413
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• 2013

In this paper, we consider several convolution sums, namely, $\mathcal{A}_i(m,n;N)$ ($i=1,2,3,4$), $\mathcal{B}_j(m,n;N)$ ($j=1,2,3$), and $\mathcal{C}_k(m,n;N)$ ($k=1,2,3,{\cdots},12$), and establish certain identities involving their finite products. Then we extend these types of product convolution identities to products involving Faulhaber sums. As an application, an identity involving the Weierstrass ${\wp}$-function, its derivative and certain linear combination of Eisenstein series is established.

• 대한수학회논문집
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• 제35권2호
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• pp.685-695
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• 2020

In this paper, we used modified tanh-coth method, combined with Riccati equation and secant hyperbolic ansatz to construct abundantly many real and complex exact travelling wave solutions to KdV-Burgers (KdVB) equation with forcing term. The real part is the sum of the shock wave solution of a Burgers equation and the solitary wave solution of a KdV equation with forcing term, while the imaginary part is the product of a shock wave solution of Burgers with a solitary wave travelling solution of KdV equation. The method gives more solutions than the previous methods.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 전문대학교육위원 P
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• pp.28-30
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• 1999

This paper proposes a robust FPID(Fuzzy Proportional Integral Derivative) controller for the LFC(load frequency control) of 2-area power system. The PID gain parameters of the proposed robust FPID controller are self-tuned by PSGM(Product Sum Gravity Method) which is very similiar to human's inference procedures. As the results of simulation, the proposed FPID controller against various load disturbances shows that it is superior to the conventional control techniques such as optimal, PID and fuzzy control in the response characteristics of frequency and tie line power flow.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.766-771
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• 1993

A mathematical model is developed to represent the batch reactor for free radical polymerization of PMMA The model is validated by comparing the simulation result with the experimental data. A computational scheme is proposed to determine the trajectory of the reactor temperature that will produce polymer product having the desired molecular weight distribution. For this instantaneous number average chain length and polydispersity are introduced to calculate the reactor temperature. The former is assumed to be a second order polynomial of the sum of the living and dead polymer concentrations. Various reactor temperature, trajectories are observed depending on the reactor conditions and prescribed molecular weight distributions. Fuzzy and PID control algorithms are applied to trace the reactor temperature trajectory. While the PID control gives rise to an overshoot when the trajectory changes its direction, the fuzzy controller yields a more satisfactory performance because it secures information on the trajectory pattern.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1997년도 추계학술대회 학술발표 논문집
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• pp.287-290
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• 1997

신경회로망은 높은 정확도의 학습 결과를 제시하는 장점을 가지고 있어서 패턴 인식을 포함한 여러 분야에서 널리 사용되어지고 있다. 그러나 신경회로망의 설계에 있어 최적의 뉴런과 층의 개수, 그리고 그 연결 등의 기하학적 해답을 제시하기가 어렵고, 서은이 우수하다고 알려진 역전파 학습 알고리즘도 오차가 없는 완벽한 학습 결과를 제시하지 못하며, 상당히 많은 학습 시간이 걸린다는 단점들을 가지고 있다. 이러한 단점들을 극복하기 위해 선형 신경회로망을 합성하는 새로운 방법을 제안하는데, 이진 함수 최소화(binary function minimization)과정을 거친 minimal-sum-of-product(MSP)를 통해서 이진 클래스 패턴(binary class pattem)을 표현 함으로써 오차가 없는 학습 결과를 얻을 수 있으며, 학습에 필요한 패턴과 학습에 걸리는 시간도 대폭 줄일수 있다. 본 논문에서는 유전자 알고리즘을 이용하여 선형 신경회로망을 합성하는 방법을 제안하며, 여러 가지 예제를 통해 제안한 방법의 우수성을 보인다.