• 한국지능시스템학회논문지
• /
• 제15권3호
• /
• pp.355-356
• /
• 2005

The problem of maximizing an OWA aggregation of a group of variables that are interrelated and constrained by a collection of linear inequalities is considered by Yager[Fuzzy Sets and Systems, 81(1996) 89-101]. He obtained how this problem can be modelled as a mixed integer linear programming problem. Recently, Carlsson et al. [Fuzzy Sets and Systems, 139(2003) 543-546] obtained a simple algorithm for exact computation of optimal solutions to a constrained OWA aggregation problem with a single constraint on the sum of all decision variables. In this note, we introduce anew approach to the same problem as Carlsson et al. considered. Indeed, it is a direct consequence of a known result of the linear programming problem.

• Steel and Composite Structures
• /
• 제4권6호
• /
• pp.453-469
• /
• 2004

In this article, a genetic algorithm based optimum design method is presented for non-linear steel frames with semi-rigid connections. The design algorithm obtains the minimum weight frame by selecting suitable sections from a standard set of steel sections such as European wide flange beams (i.e., HE sections). A genetic algorithm is employed as optimization method which utilizes reproduction, crossover and mutation operators. Displacement and stress constraints of Turkish Building Code for Steel Structures (TS 648, 1980) are imposed on the frame. The algorithm requires a large number of non-linear analyses of frames. The analyses cover both the non-linear behaviour of beam-to-column connection and $P-{\Delta}$ effects of beam-column members. The Frye and Morris polynomial model is used for modelling of semi-rigid connections. Two design examples with various type of connections are presented to demonstrate the application of the algorithm. The semi-rigid connection modelling results in more economical solutions than rigid connection modelling, but it increases frame drift.

• 대기
• /
• 제24권2호
• /
• pp.197-206
• /
• 2014

The effects of different averaging operators and atmospheric stability on the turbulent fluxes are investigated using the vertical velocity, air temperature, carbon dioxide concentration, and absolute humidity data measured at 10 Hz by a 3-dimensional sonic anemometer and an open-path $CO_2/H_2O$ infrared gas analyzer installed at a height of 18.5 m on the rooftop of the Jungnang KT building located at a typical residential area in Seoul, Korea. For this purpose, 7 different averaging operators including block average, linear regression, and moving averages during 100 s, 300 s, 600 s, 900 s, and 1800 s are considered and the data quality control procedure such as physical limit check and spike removal is also applied. It is found that as the averaging interval becomes shorter, turbulent fluxes computed by the moving average become smaller and the ratios of turbulent fluxes computed by the 100 s moving average to the fluxes by the 1800 s moving average under unstable stability are smaller than those under neutral stability. The turbulent fluxes computed by the linear regression are 85~92% of those computed by the 1800 s moving average and nearly the same as those computed by 900 s moving average, implying that the adequate selection of an averaging operator and its interval will be very important to estimate more accurate turbulent fluxes at urban area.

• 대한산업공학회지
• /
• 제34권2호
• /
• pp.216-222
• /
• 2008

The determination of spectrum charges for the operators is a main issue to efficiently manage the limited radio spectrum resources. In this paper, we propose a model to compute the optimal charges for radio spectrum usage. The objective is to determine that will maximize the spectrum charges, and decision variables of ratios for actual or estimated revenues are considered. The spectrum charges are maximized under satisfying the least profit for operators based on Log-Linear demand function. The parameters of actual sales and minimum profit of operators are analyzed to make an efficient management for radio spectrum. The results show that the spectrum charges increase as the actual sales increase, but it decrease as the required minimum profit of operator increases. It is also observed that the government should increase the ratio for estimated sales if anticipating the poor market in the future, otherwise they should increase the ratio for actual sales to maximize the spectrum charges.

• 유통과학연구
• /
• 제17권6호
• /
• pp.15-23
• /
• 2019

Purpose - This study evaluates the effects of e-marketing communication on brand loyalty in the mobile communication market in Kosovo. given that no prior studies of this nature are found. It explores the relationships, between e-marketing communication, brand image and customer satisfaction, and their impact on the brand loyalty. Research design, data, and methodology - The research model of four constructs was developed. The data was collected via online surveys, 423 completed surveys from mobile subscribers were received. To test the relationship between the individual variables and multiple variables with the dependent variable several test were performed including data validity and reliability, bivariate correlation, simple linear and multiple regression analysis using stepwise method. Results - Positive significant effect of e-Marketing communication on brand loyalty, as well its significant effect on both brand image and customer satisfaction, which subsequently have significant impact on brand loyalty as it was confirmed by previous studies. Conclusions - The findings confirm that e-Marketing communication is key factor in building well perceived brand image, fostering customer satisfaction, and leading to customer commitment and loyalty towards brands of mobile operators in Kosovo.

• 농촌지도와개발
• /
• 제27권2호
• /
• pp.65-74
• /
• 2020

The study aims to identify the factors affecting business performance of rural tourism operators. For this study, 1,004 questionnaires were collected by field survey of rural tourism operators. The linear multiple regression analysis were used to identify factors affecting performance of rural tourism business. The result indicate that the factors influencing the sales of rural tourism business were in order of owning sales facilities, perception of multi-functional value of agriculture and rural, group promotion, number of rooms, and gender. In the case of gender, it was found that females had a high probability of positively affecting sales. The factors influencing the satisfaction of the rural tourism business were in the order of management strategy, number of days of operation, perception of multi-functional value of agriculture and rural, and business career. In the case of management strategy, it was found that the differentiation strategy have a positively affecting the satisfaction of the rural tourism business. As for the business career, the shorter the career, the higher the probability of positively affecting the satisfaction of the rural tourism business. The results of this study would be useful for establishing strategies to improve the management performance of the rural tourism business.

• 대한수학회보
• /
• 제38권4호
• /
• pp.663-668
• /
• 2001

X and Y are Banach spaces for which K(X, Y), the space of compact operators from X to Y, is an M-ideal in L(X, Y), the space of bounded linear operators form X to Y. If Z is a closed subspace of Y such that L(X, Z) has property SU in L(X, Y) and d(T, K(X, Z)) = d(T, K(X, Y)) for all $T \in L(X, Z)$, then K(X, Z) is an M-ideal in L(X, Z) if and only if it has property SU is L(X, Z).

• Korean Journal of Mathematics
• /
• 제19권2호
• /
• pp.205-209
• /
• 2011

Let $\mathcal{QA}$ denote the class of bounded linear Hilbert space operators T which satisfy the operator inequality $T^*|T^2|T{\geq}T^*|T|^2T$. Let $f$ be an analytic function defined on an open neighbourhood $\mathcal{U}$ of ${\sigma}(T)$ such that $f$ is non-constant on the connected components of $\mathcal{U}$. We generalize a theorem of Sheth [10] to $f(T){\in}\mathcal{QA}$.

• 호남수학학술지
• /
• 제28권4호
• /
• pp.533-541
• /
• 2006

let E be a Finsler modules over $C^*$-algebras. A with norm-map $\rho$ and L(E) set of all A-linear bonded operators on E. We show that the canonical homomorphism ${\phi}:L(E){\rightarrow}L(E_I)$ sending each operator T to its restriction $T|E_I$ is injective if and only if I is an essential ideal in the underlying $C^*$-algebra A. We also show that $T{\in}L(E)$ is a bounded below if and only if ${\mid}{\mid}x{\mid}{\mid}={\mid}{\mid}{\rho}{\prime}(x){\mid}{\mid}$ is complete, where ${\rho}{\prime}(x)={\rho}(Tx)$ for all $x{\in}E$. Also, we give a necessary and sufficient condition for the equivalence of the norms generated by the norm map.

• Kyungpook Mathematical Journal
• /
• 제56권4호
• /
• pp.1141-1160
• /
• 2016

In this paper, a symbolic algorithm for solving a regular initial value problem (IVP) for a system of linear differential-algebraic equations (DAEs) with constant coeffcients has been presented. Algebra of integro-differential operators is employed to express the given system of DAEs. We compute a canonical form of the given system which produces another simple equivalent system. Algorithm includes computing the matrix Green's operator and the vector Green's function of a given IVP. Implementation of the proposed algorithm in Maple is also presented with sample computations.