• Korean Journal of Mathematics
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• v.18 no.3
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• pp.243-252
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• 2010

In this paper we extend the projective properties of representations of a quiver $Q={\bullet}{\rightarrow}{\bullet}$ as left R-modules to the projective properties of representations of quiver $Q={\bullet}{\rightarrow}{\bullet}$ as left $R[x]$-modules. We show that if P is a projective left R-module then $0{\rightarrow}P[x]$ is a projective representation of a quiver $Q={\bullet}{\rightarrow}{\bullet}$ as $R[x]$-modules. And we show $0{\rightarrow}L$ is a projective representation of $Q={\bullet}{\rightarrow}{\bullet}$ as R-module if and only if $0{\rightarrow}L[x]$ is a projective representation of a quiver $Q={\bullet}{\rightarrow}{\bullet}$ as $R[x]$-modules. Then we show if P is a projective left R-module then $R[x]\longrightarrow^{id}P[x]$ is a projective representation of a quiver $Q={\bullet}{\rightarrow}{\bullet}$ as $R[x]$-modules. We also show that if $L\longrightarrow^{id}L$ is a projective representation of $Q={\bullet}{\rightarrow}{\bullet}$ as R-module, then $L[x]\longrightarrow^{id}L[x]$ is a projective representation of a quiver $Q={\bullet}{\rightarrow}{\bullet}$ as $R[x]$-modules.

• Communications for Statistical Applications and Methods
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• v.6 no.2
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• pp.645-658
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• 1999

One of the most popular graphical techniques for goodness of fit problems is the quantile-quantile plot(Q-Q plot) Easton and McCulloch(1990) suggested a way of generalizing Q-Q plots to multivariate cases bases on finding a matching between the points of the data set whose shape is being examined and a reference sample. in this paper we investigated the asymptotic behavior of the generalized Q-Q plot for bivariate cases. As a result we concluded that the standard univariate Q-Q plot and the generalized Q-Q plot have the same limit if two variables are independent.

• Journal of Ecology and Environment
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• v.35 no.3
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• pp.227-234
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• 2012

Quercus aliena and Q. serrata are both occur as natural vegetation alongside natural freshwater bodies of the southern Korea Peninsula. Q. serrata dominates over Q. aliena as secondary forest vegetation in the present day. In order to explain these natural distributional traits of the oak species, we conducted some experiments with oak seedlings which treated with major important environmental resources, including light, moisture and nutrients, under controlled conditions. We then measured the ecological niche breadths and overlap from 15 eco-morphological characteristics. The ecological niche breadth of Q. aliena and Q. serrata were higher in terms of the nutrient factor applied, but was lower terms of light. The niche breadth of Q. serrata was wider than that of Q. aliena in light and moisture exposure. On the other hand, the niche breadth of Q. aliena was similar with that of Q. serrata in terms of the nutrient factor applied. These results imply that Q. serrata has a broader ecological distribution in over a wider variety of light and moisture environments than that of Q. alien. Ecological niche overlap between two oak species was the widest in terms of the light treatment factor applied, and narrowest in terms of moisture. This response pattern was also verified by cluster and principle component analysis. These results suggest competitive interactions between Q. serrata and Q. aliena seedlings may be higher for light resources than moisture or nutrient resources, and that Q. serrata is more shade tolerant than Q. aliena.

• Journal of IKEEE
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• v.25 no.3
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• pp.578-583
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• 2021

This paper describes acceleration tests for reliability of semiconductors. It also describes AEC-Q100, international test standard for reliability of automotive semiconductors. Semiconductors can be used for dozens of years. So acceleration tests are essential to test potential problems over whole period of product where test time is minimized by applying intensive stresses. AEC-Q100 is a typical acceleration test in automotive semiconductors, and it is designed to find various failures in semiconductors and to analyze their causes of occurance. So it finds many problems in design and fabrication as well as it predicts lifetime and reliability of semiconductors. AEC-Q100 consists of 7 test groups such as accelerated environmental stress tests, accelerated lifetime simulation tests, package assembly integrity tests, die fabrication reliability tests, electrical verification tests, defect screening tests, and cavity package integrity tests. It has 4 grades from grade 0 to grade 3 based on operational temperature. AEC-Q101, Q102, Q103, Q104, and Q200 are applied to discrete semiconductors, optoelectronic semiconductors, sensors, multichip modules, and passive components, respectively.

• Journal of the Korean School Mathematics Society
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• v.17 no.4
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• pp.805-816
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• 2014

In this paper, we survey the development of material implication and we present an analysis of the students' understanding of formal implication. Most of high school students consider material implication $p{\rightarrow}q$ as ${\sim}p{\vee}q$ when they represent the pattern of a collected cards as material implication $p{\rightarrow}q$. But when they collect cards in which material implication $p{\rightarrow}q$ is true, Most of high school students consider $p{\rightarrow}q$ as $p{\wedge}q$.

• The Journal of Information Systems
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• v.32 no.1
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• pp.201-221
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• 2023

Purpose Customers consider the overall experience with the company as important as the quality of the product, and companies are also paying attention to creating long-term relationships with customers through optimal customer experiences. In this study, we propose a customer experience management process called 'CX-Q', which combines customer journey map and Q-methodology to understand the importance of customer experience based on the overall customer experience. Design/methodology/approach. CX-Q is a process that combines Q-methodology and customer journey maps, allowing stakeholders to explore and improve customer experiences at each contact point while engaging with brands, products, and services. It also enables them to derive customer experience insights and important management points for each segment. To demonstrate the usefulness of the proposed CX-Q, this study analyzed the experience of customers who used the Airbnb travel platform service as an example, applying the CX-Q process. Findings A total of four customer segments were derived, and it was found that each segment valued different attributes during the customer journey stage. The customer experience analysis using the CX-Q process proposed in this study is expected to help understand customers in more detail and assist in managing and improving customer experience.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.46-53
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• 2016

The purpose of this study is to analyze the cognizance of AIDS by applying the Q methodology, as well as to provide preliminary data for developing AIDS prevention campaigns. A Q population was identified from a literature search and in-depth interviews. The study process analyzed the P sample, the study participants, using the Q-sorting methodology to produce the Q sample, which is composed of statements from October 20 to 27, 2014. 20 participants (analyzed) 27 statements and 3 types of AIDS cognizance were produced as a result. These types are 1(N=9), 2(N=6), and 3(N=5), which correspond to denial, social support, and selfish motivation, respectively. The members of the denial type had a strongly negative opinion about AIDS, whereas the social support type showed a friendly gesture. The selfish motivation type took a neutral stance. The common and different points, as well as the distinctive features of these types, were studied. The accomplishments of this study include suggesting an efficient strategy for making an AIDS control policy, as well as a qualitative analysis, through the employment of the Q-methodology, which is useful for understanding human beings' (internal viewpoint).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.313-314
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• 2005

Organic light emitting diodes(OLEDs) are widely used as one of the information display techniques. We synthesized (1,10-phenanthroline)- (8-hydroxyquinoline) [Zn(Phen)q]. We studied the improvement of OLEDs properties using Zn(phen)q. The Ionization Potential(IP) and the Electron Affinity(EA) of Zn(phen)q investigated using cyclic voltammetry(CV). The IP, EA and Eg were 7.leV, 3.4eV and 3.7eV, respectively. The PL spectrum of Zn(phen)q was yellowish green as the wavelength of 535nm. In this study, we used Zn(phen)q as electron transporting layer(ETL) inserted between emitting layer(EML) and cathode. As a result, Zn(phen)q is useful as electron transporting layer to enhance the performance of OLEDs.

• Kyungpook Mathematical Journal
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• v.50 no.4
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• pp.473-482
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• 2010

In the present paper we define a q-extension of the Leibniz rule for q-derivatives via Weyl type q-derivative operator. Expansions and summation formulae for the generalized basic hypergeometric functions of one and more variables are deduced as the applications of the main result.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.5
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• pp.927-931
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• 2010

Recently, high luminance and high efficiency were realized in OLED with multilayer structure including emitting materials such as metal-chelate complexes. We synthesized a new luminescent material, namely, [2-(2-hydroxyphenyl)quinoline] (Zn(HPB)q) which has low molecular compound and emitted in yellowish green region. The ionization potential(IP) and electron affinity(EA) of Zn(HPB)q were measured by cyclic-voltammetry(CV). As a result, IP and EA of Zn(HPB)q were calculated 6.8 eV and 3.5 eV, respectively. We fabricated the devices and observed the possibility of Zn(HPB)q as electron transporting layer. We have obtained an improvement of luminance and decrease of turn-on voltage using Zn(HPB)q as electron transporting layer.