• Journal of the Korean Mathematical Society
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• v.60 no.5
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• pp.959-986
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• 2023

Zhai and Lin recently proved that if G is an n-vertex connected 𝜃(1, 2, r + 1)-free graph, then for odd r and n ⩾ 10r, or for even r and n ⩾ 7r, one has ${\rho}(G){\leq}{\sqrt{{\lfloor}{\frac{n^2}{4}}{\rfloor}}}$, and equality holds if and only if G is $K_{{\lceil}{\frac{n}{2}}{\rceil},{\lfloor}{\frac{n}{2}}{\rfloor}}$. In this paper, for large enough n, we prove a sharp upper bound for the spectral radius in an n-vertex H-free non-bipartite graph, where H is 𝜃(1, 2, 3) or 𝜃(1, 2, 4), and we characterize all the extremal graphs. Furthermore, for n ⩾ 137, we determine the maximum number of edges in an n-vertex 𝜃(1, 2, 4)-free non-bipartite graph and characterize the unique extremal graph.

• Bulletin of the Korean Mathematical Society
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• v.60 no.4
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• pp.1003-1016
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• 2023

In this paper, we introduce the idea of twisted product lightlike submanifolds of semi-Riemannian manifolds and provide non-trivial examples of such lightlike submanifolds. Then, we prove the non-existence of proper isotropic or totally lightlike twisted product submanifolds of a semi-Riemannian manifold. We also show that for a twisted product lightlike submanifold of a semi-Riemannian manifold, the induced connection ∇ is not a metric connection. Further, we prove that a totally umbilical SCR-lightlike submanifold of an indefinite Kaehler manifold ${\tilde{M}}$ does not admit any twisted product SCR-lightlike submanifold of the type M_⊥×_ϕM_T, where M_⊥ is a totally real submanifold and MT is a holomorphic submanifold of ${\tilde{M}}$. Consequently, we obtain a geometric inequality for the second fundamental form of twisted product SCR-lightlike submanifolds of the type M_T×_ϕM_⊥ of an indefinite Kaehler manifold ${\tilde{M}}$, in terms of the gradient of ln ϕ, where ϕ stands for the twisting function. Subsequently, the equality case of this inequality is discussed. Finally, we construct a non-trivial example of a twisted product SCR-lightlike submanifold in an indefinite Kaehler manifold.

• Journal of the Korean Society of Food Culture
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• v.24 no.2
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• pp.172-180
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• 2009

The purpose of this study was to investigate the consumer characteristics in foodservice according to university students' lifestyles. The data were collected by the questionnaire survey of 520 university students from Daegu Gyeongbuk Province. The SPSS/Win 12.0 program was used to analyse the samples. The results are as follows: 1) Lifestyle was divided into 10 factors and 3 clusters, namely "Convenience Intention" (cluster I), "Health Information Intention" (cluster II), and "Gender Equality Intention" (cluster III). 2) The differences in general characteristics between the three clusters were founded on gender, frequency of visits, companion, information type, and the type of restaurant. 3) The characteristics of cluster I (Convenience Intention) are explained by it consisting of the group with low averages in consumer dissatisfaction, complaints, compensation, and repurchase intention, where as cluster II was the high average group and cluster III the middle average group. Based on these results, consumer characteristics in foodservice are discussed.

• Journal of Distribution Science
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• v.14 no.11
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• pp.29-36
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• 2016

Purpose - Intense debate is occurring over support for farmers in Korea, specifically on the justification, policy design, and equality issues of the farm support programs. Given this debate, a new type of farm program in the US, a market flexible revenue program(the Average Crop Revenue Election, ACRE), is examined. ACRE stands in contrast to traditional programs that tie payments to price and have parameters that are fixed or change only infrequently. Research design, data, and methodology - Based on the ACRE program formulas, the potential payments are estimated by crop year, program crop and geographical area using the FSA acreage and payment rate data. Results - If all US farm program acres were in ACRE over the 2009-2013 crop years, payments would have totaled $7.95 billion or 1.2 percent of average market receipts for US crops. Enacting ACRE as a revenue program instead of a similarly-structured price-only program increased payments by $1.75 billion or 28 percent. Conclusions - Potential payments by ACRE largely reflected the distribution of the value of production across the program crops eligible for ACRE as well as across state geographical areas. If program parameters can be made acceptable and if data availability issues can be addressed, market flexible revenue programs offer a farm policy option that can address many of the concerns that have arisen over farm policy in Korea.

• Interdisciplinary Bio Central
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• v.2 no.2
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• pp.4.1-4.6
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• 2010

The most common type of microarray experiment has a simple design using microarray data obtained from two different groups or conditions. A typical method to identify differentially expressed genes (DEGs) between two conditions is the conventional Student's t-test. The t-test is based on the simple estimation of the population variance for a gene using the sample variance of its expression levels. Although empirical Bayes approach improves on the t-statistic by not giving a high rank to genes only because they have a small sample variance, the basic assumption for this is same as the ordinary t-test which is the equality of variances across experimental groups. The t-test and empirical Bayes approach suffer from low statistical power because of the assumption of normal and unimodal distributions for the microarray data analysis. We propose a method to address these problems that is robust to outliers or skewed data, while maintaining the advantages of the classical t-test or modified t-statistics. The resulting data transformation to fit the normality assumption increases the statistical power for identifying DEGs using these statistics.

• Korean Institute of Interior Design Journal
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• v.22 no.4
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• pp.149-157
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• 2013

As a period of pluralism, today's museum architecture has been expanding social and cultural meaning. So, Various expressions are appearing in museum architecture. Accordingly, the museum must be very reproducible and comply with aesthetic requirements. At the same time, museum construction in urban design and features must satisfy professional requirements. SANAA is one of contemporary architects has been decisively deleted existing fixed and functional layout type of program through 'The new hierarchy'. Thus, the experience of the space will vary. Now, museum space is urgently needed than ever before crustal movements. Thus, this study aims to contribute an alternative to the museum space configuration according to the trend of the times through 'The new hierarchy' of SANAA. This paper is limited to the cases of the SANAA's museum architecture. We analyze the characteristics of representation on 'The new hierarchy' appear in the museum space configuration and then, examine the value of the spatial. SANAA's 'New Hierarchy' is going to set the cognitive boundary by expression targeting plane and the surface. It is completely different than the previous boundaries. Characteristics of the expression represents non-centrality, decentrally, non-oriented, uncertainty, non-territorialization, uniformity. It is steady that identity of Space, Human, Environment in Museum. They have a relationship each concept of Independence, autonomy, equality.

• Structural Engineering and Mechanics
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• v.63 no.1
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• pp.23-35
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• 2017

A nonlinear static procedure considering work-energy principle and global failure mechanism to estimate base shears of reinforced concrete (RC) frame-type structures is presented. The relative energy equation comprising of elastic vibrational energy, plastic strain energy and seismic input energy is obtained. The input energy is modified with a factor depending on damping ratio and ductility, and the energy that contributes to damage is obtained. The plastic energy is decreased with a factor to consider the reduced hysteretic behavior of RC members. Given the pre-selected failure mechanism, the modified energy balance equality is written using various approximations for modification factors of input energy and plastic energy in scientific literature. External work done by the design lateral forces distributed to story levels in accordance with Turkish Seismic Design Code is calculated considering the target plastic drift. Equating the plastic energy obtained from energy balance to external work done by the equivalent inertia forces considering, a total of 16 energy-based base shears for each frame are derived considering different combinations of modification factors. Ductility related parameters of modification factors are determined from pushover analysis. Relative input energy of multi degree of freedom (MDOF) system is approximated by using the modal-energy-decomposition approach. Energy-based design base shears are compared with those obtained from nonlinear time history (NLTH) analysis using recorded accelerograms. It is found that some of the energy-based base shears are in reasonable agreement with the mean base shear obtained from NLTH analysis.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.529-534
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• 2005

In this paper, a new type of output feedback control, called a $H_2/H_{\infty}$ fnite memory control (FMC), is proposed for deterministic state space systems. Constraints such as linearity, unbiasedness property, and finite memory structure with respect to an input and an output are required in advance to design $H_2/H_{\infty}$ FMC in addition to the performance criteria in both $H_2$ and $H_{\infty}$ sense. It is shown that $H_2$, $H_{\infty}$, and mixed $H_2/H_{\infty}$ FMC design problems can be converted into convex programming problems written in terms of linear matrix inequalities (LMIs) with some linear equality constraints. Through simulation study, it is illustrated that the proposed $H_2/H_{\infty}$ FMC is more robust against uncertainties and faster in convergence than the existing $H_2/H_{\infty}$ output feedback control schemes.

• Human Ecology Research
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• v.53 no.2
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• pp.195-208
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• 2015

This study explored general marriage migration for 180 unmarried Vietnamese immigrant women and identified differences in recognition after the choice of marriage. The methods used were frequency analysis, kai verification, and independent t verification were conducted. The findings were as follows. First, unmarried Vietnamese women showed a receptive attitude towards marriage migration with the less-educated group more likely to opt for marriage migration. Economic benefit expectations topped other factors in regards to the image of marriage migrant women and motivation. Dual national identity benefits were also indicated. Second, the perception of external and illusionary images of the spouses of marriage migrant women was low; however, the perception of good occupations and gender equality was high. A vague expectancy of marriage was also found. The perception was high that children from multi-cultural families would be global bilingual talents and adjust to school; however, the perception of social discrimination or prejudice was low. The perception of social discrimination was low concerning the perception of social integration towards marriage migrant women; however, the perception of identities, cultural differences and employment was present. By contrast, the group opting for marriage migration showed a significantly low perception of social discrimination and difficulty in employment. The suggested measures are to regulate and maintain forms of marriage type, reinforce prior training systems for Vietnamese immigrant women (and spouses), enhance multicultural recognition, and supplement multicultural policies.

• Human Ecology Research
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• v.52 no.6
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• pp.551-560
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• 2014

In this study, we have focused on various types of costumes for traditional Ganggangsullae and daily dance Ganggangsullae. To analyze their costumes, spot photographs of Ganggangsullae contests from 2011 and 2013 were collected from the Department of Culture and Tourism, Jindo County Office and the Jeonnam Information & Culture Industry Promotion Agency. Costumes were analyzed by categorising them as type, shape and color. Traditional Ganggangsullae costumes are two types: traditional hanbok and saenghwal hanbok. Traditional hanbok design dates back to the late Joseon dynasty and saenghwal hanbok design to the middle Joseon Dynasty. They reflects confucianism, a male-dominated society, totemism, shamanism and Yin-Yang and the five elements theory in agrarian society and community life. Daily dance Ganggangsullae has various types of costumes such as the fusion hanbok, saenghwal hanbok, cheering uniform and casual wear. They show modern color schemes. There is not any magical meaning from Yin-Yang and the five elements theory. Instead, they have individualism, liberty, equality and welfare in information-oriented society. So its costumes are easy and comfortable clothes. But traditional hanbok, fusion hanbok and saenghwal hanbok are inspired from Korean identiry. Even though traditional Ganggangsullae and daily dance Ganggangsullae have different costumes and ideology, they have a common denominator 'playfulness.' It will function as a key for Ganggangsullae to be performed continuously over the period.