• Korea-Australia Rheology Journal
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• v.17 no.1
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• pp.1-7
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• 2005

Acrylonitrile-Butadiene-Styrene (ABS), polycarbonate (PC) and their alloys are an important class of engineering thermoplastics that are widely used for automotive industry, computer and equipment housings. For the process of recycling mixtures of ABS and PC, it is desirable to know how sensitive the blend properties are to changes in compositions. It was for this reason that blends of virgin ABS and virgin PC at five different compositions, namely, $15\%,\;30\%,\;50\%,\;70%$ and $85\%$ by weight of ABS were prepared and characterised by rheological and mechanical measurements. Rheological properties of these blends in steady, oscillatory and transient step shear and mechanical properties, namely, tensile strength, elongation-at-break and Izod impact strength are reported. The results show that PC behaves in a relatively Newtonian manner, but ABS exhibits significant shear thinning. The ABS-rich blends show a trend that is similar to that of ABS, while PC-rich blends, namely $0\%$ and $15\%$, exhibit a nearly Newtonian behaviour. However, at a fixed shear rate or frequency, the steady shear or the dynamic viscosity varied respectively in a non-mono-tonic manner with composition. Except for $15\%$ blend, the viscosities of other blends fall into a narrow band indicating a wide-operation window of varying blend ratio. The blends exhibited a lower viscosity than either of the two pure components. The other noticeable feature was that the blends at $70\%$ and $85\%$ ABS content had a higher G' than pure ABS, indicating an enhancement of elastic effect. The tensile yield strength of the blends followed the 'rule of mixtures' showing a decreasing value with the increase of ABS content in PC. However, the elongation-at-break and the impact strength did not appear to obey this 'rule of mixtures,' which suggests that morphology of the blends also plays a significant role in determining the properties. Indeed, scanning electron micrographs of the fracture surfaces of the different blends validate this hypothesis, and the $15\%$ blend is seen to have the most distinct morphology and correspondingly different behaviour and properties.

• The Korean Journal of Cytopathology
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• v.9 no.1
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• pp.69-78
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• 1998

There is a lot of difficulty in the diagnosis of follicular lesions of the thyroid by fine needle aspiration cytology(FNAC). The main purpose of this report is offering more guidance regarding the cytologic appearance to distinguish follicular neoplasm from nodular golfer and laying stress on the presence of mixed group. The histologic and cytologic findings of 23 follicular neoplasms and 13 nodular (adenomatous) getters were reviewed. Histologic specimens were classified into the microfollicular(MIF), mixed(MIX), and nodular getter(NG) groups. The comparison of histologic patterns with histologic diagnosis revealed that all the lesions with predominantly microfollicular, trabecular, or solid pattern were follicular carcinoma and all the lesions with predominantly macrofollicular pattern were nodular goiter. The distinguishing cytologic features for the MIF group were irregular cell arrangement in cell groups(100%, p=0.00001), absence of atrophic follicular cells(100%, p=0.0007), abundant microfollicles(100%, 0=0.002), pleomorphic nuclei(100%, p=0.002), not predominant syncytial smear pattern(100%, p=0.002), heterochromatin(100%, p=0.032), absence of macrofollicles(100%, p=0.038), scant colloid(100%, 0=0.04), clear back-ground(83%, p=0.00006), and uniform sized follicles(83%, p=0.014). And regular cell arrangement(honeycomb appearance) in cell groups(85%, p=0.0000), atrophic change of follicular cells(69%, p=0.0002), syncytial smear pattern(54%, p=0.000), monomorphic nuclei(85%, p=0.008), and hemorrhagic background(100%, p=0.027) were characteristic features of the NG group. Seventeen out of 36 cases(47%) were the MIX group composed of combined cytologic features of the MIF and NG groups. Therefore the frequent presence of the MIX group is considered to be main cause of the difficulty in the diagnosis of follicular lesions by FNAC. The mixed morphologic feature may support the hypothesis of a biologic 'continuum' between nodular goiter and follicular neoplasm of thyroid gland.

• The Journal of Industrial Distribution & Business
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• v.9 no.2
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• pp.47-55
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• 2018

Purpose - To meet the needs of various customers in an uncertain market environment, many companies use product modularization strategies. Modularization of a product means that one product consists of several components and that the type of product can be changed according to the combination of components. The greatest feature of modularity is that changes in one component do not significantly affect the physical changes in the other component to which they are connected. Modularization of products is recognized as a very important strategy to reflect increasingly complicated customer requirements to products and respond to the needs of various markets. Many studies have been made in connection with the concept of mass customer satisfaction. There are many prior studies that modularization of such products positively affects the operational performance (manufacturing cost, fast delivery, etc.) and innovation of the product. However, excessive modularization has been found to have a negative effect on this performance. However, there are very few studies on the nonlinear relationship between product modularization and customer satisfaction. Supplementing these academically insufficient parts is very necessary when considering the current market environment. Research design, data, and methodology - In order to make up for the shortcomings of academic research in Korea, this study collects data through questionnaires in electronic, auto, and defense industry. This is because these industries are using modularity of products. based on lots of previous studies and information overload theory, we made two hypothesis and verify with empirical analysis. All 108 data were used. We used the R program and SPSS program for statistical verification. Results - As a result of the study, modularization of products showed positive relationship with customer satisfaction to a certain level. However, it has been found that when the modularization is over and beyond a certain level, there is a negative relationship with customer satisfaction. Conclusions - Excessive modularization of products can have a negative impact on customer satisfaction. This result can be understood as a result of human limited rationality due to information overload. Therefore, it is important for companies to apply appropriate modularity to product design.

• Journal of Astronomy and Space Sciences
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• v.34 no.2
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• pp.105-110
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• 2017

Solar wind density depletions are phenomena that solar wind density is rapidly decreased and keep the state. They are generally believed to be caused by the interplanetary (IP) shocks. However, there are other cases that are hardly associated with IP shocks. We set up a hypothesis for this phenomenon and analyze this study. We have collected the solar wind parameters such as density, speed and interplanetary magnetic field (IMF) data related to the solar wind density depletion events during the period from 1996 to 2013 that are obtained with the advanced composition explorer (ACE) and the Wind satellite. We also calculate two pressures (magnetic, dynamic) and analyze the relation with density depletion. As a result, we found total 53 events and the most these phenomena's sources caused by IP shock are interplanetary coronal mass ejection (ICME). We also found that solar wind density depletions are scarcely related with IP shock's parameters. The solar wind density is correlated with solar wind dynamic pressure within density depletion. However, the solar wind density has an little anti-correlation with IMF strength during all events of solar wind density depletion, regardless of the presence of IP shocks. Additionally, In 47 events of IP shocks, we find 6 events that show a feature of blast wave. The quantities of IP shocks are weaker than blast wave from the Sun, they are declined in a short time after increasing rapidly. We thus argue that IMF strength or dynamic pressure are an important factor in understanding the nature of solar wind density depletion. Since IMF strength and solar wind speed varies with solar cycle, we will also investigate the characteristics of solar wind density depletion events in different phases of solar cycle as an additional clue to their physical nature.

• Journal of the Korean Society for Library and Information Science
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• v.27
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• pp.161-181
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• 1994

As information technologies are applied to the libraries in information society, the library services have been changing its feature. Therefore, the purpose of this paper is to explore and to establish a paradigm of the library services in information society. It is hypothesized that the application of information technologies leads to the change of the library services in information society. To prove the hypothesis, the data were collected from various research results carried out in the developed countries and by observing various libraries where the information technologies are extensively applied. The findings are as follows: 1. As information technologies are applied to the library, many new library services emerge for the society. 2. As the electronic data replace the paper data, the collection of a library becomes the collection of the libraries in the world. Therefore, the accessibility to the information network is more important than to own information in the library. Librarians select various electronic data according to the library policy which distinguishes their own library collection from others. The policy also solves the various problems related to weeding and preserving library collection. And the use of CD-ROM selection tools enable library users to select their own data. Now, the censorship becomes the concems of the library users, not the library. 3. The catalogs are reorganized for the electronic data for the international use. The most important information in the catalog is the location of the data and the multi access to the data are necessary. 4. As the information technologies are applied in book selection, cataloguing, information retreival and circulation, the library users are enable to service themselves in the library. And most of the routine works related to the information service are taken over by the library staffs. Professional librarians engage in user education, information marketing and fund raising. 5. Public libraries in information society serves those who have no access to the information. They help the illiterates. patients in the hospital, prisoners, and homeless in the city. Therefore, the information technologies enhance the role of librarians in professional work in the library as well as in the information society.

• Geomechanics and Engineering
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• v.4 no.3
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• pp.173-190
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• 2012

With recent growing interests in the Performance-Based Seismic Design and Assessment Methodology, more realistic modeling of a structural system is deemed essential in analyzing, designing, and evaluating both newly constructed and existing buildings under seismic events. Consequently, a shallow foundation element becomes an essential constituent in the implementation of this seismic design and assessment methodology. In this paper, a contact interface fiber section element is presented for use in modeling soil-shallow foundation systems. The assumption of a rigid footing on a Winkler-based soil rests simply on the Euler-Bernoulli's hypothesis on sectional kinematics. Fiber section discretization is employed to represent the contact interface sectional response. The hyperbolic function provides an adequate means of representing the stress-deformation behavior of each soil fiber. The element is simple but efficient in representing salient features of the soil-shallow foundation system (sliding, settling, and rocking). Two experimental results from centrifuge-scale and full-scale cyclic loading tests on shallow foundations are used to illustrate the model characteristics and verify the accuracy of the model. Based on this comprehensive model validation, it is observed that the model performs quite satisfactorily. It resembles reasonably well the experimental results in terms of moment, shear, settlement, and rotation demands. The hysteretic behavior of moment-rotation responses and the rotation-settlement feature are also captured well by the model.

• Proceedings of the Korean Society for Language and Information Conference
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• 2001.06a
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• pp.237-257
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• 2001

This paper investigates the idiosyncratic understanding of universal quantifiers such as every, each or all by young children at the ages of 4 to 7, and argues that the phenomenon is explicable in terms of the maturation of both the cognitive system and the linguistic system. Evidence for this dual explanation comes from the fact that the visual input, a picture, plays a key role in determining the children’s conceptual representation, suggesting the need for the central integration of visual and linguistic elements; and from the fact that a quantifier in the linguistic input has an intrinsic property, i.e. a <+focus> feature. I have tried to explain the nature of the cognitive factors in terms of the function of the central system, suggesting a modified form of Smith & Tsimpli’s (1995) version of Fodor’s (1983) modularity hypothesis. Conceptual representations of two kinds are in competition with each other and they are integrated into a neutral LOT (Language of Thought) representation at some point . In the process of this integration, the representations from the visual input predominate over those from the auditory input, though the quantize. (treated as new information provided by the latter) is salient in the final representations. When visual conceptual representations predominate over purely linguistic ones, quantifier spreading errors occur. By contrast, when the relevant grammatical knowledge has developed sufficiently to counteract the conceptual representations, this peculiar behaviour by children should disappear. It is argued that children have to learn two kinds of grammatical fact with regard to universal quantification: (i) they have to learn the status of the quantifier as a functional head of DP so that it has to be positioned inside DP; and (ii) they have to learn the Left-Branch Condition which specifies that movement of an element in the left-branch position is possible only by pied-piping the entire phrase.

• KDI Journal of Economic Policy
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• v.33 no.2
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• pp.41-79
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• 2011

This study examines the compensation scheme for the executives and risk-taking behavior in the Korean banks. Theoretically, shareholders prefer risky asset choice to the optimal one due to the limited liability feature of reward, and stock-based executive compensation may induce choices favorable to the shareholder. We empirically test this risk-taking hypothesis using Korean banks' data. Since only the stock option data is available under the current disclosure system, we limit our analysis to examine the relationship between the compensation through stock option and the risk of banks. The result provides no evidence that stock option compensations increase the risk of banks, which is contrary to the theoretical prediction and preceding studies in the US. This may be due to any factor that the executive reward data omit, or regulation effects on the bank management.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.3
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• pp.660-672
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• 2007

Today venture holds highly skilled technical manpower and high-tech products. To maintain the superiority in competition in the market, it is necessary to complete preparations, first of all, the effectual global marketing strategy should take precedence over the others. Therefore, this research is based on the research report of the special feature, the state of affairs and marketing strategy of venture business and is made up the questionnaire to interview total 200 companies of venture that was registered in Dec. 2006 and then is made the analysis of relevance of the statistical data of 154 companies of them and set up a hypothesis. As the result of it, it is set up two hypotheses. One of them is the difference of products, price, distribution and promotion according to the growth period. And the other is the difference of distribution and promotion according to the turnover. The venture places the great deal of weight on the discriminatory products concerned technical development and marketing activity. It is pointed out that it is to be passive to seek a new market promote the products, because of limitations of manpower, funds, technology and information in the beginning with smalt turnover.

• The Korean Journal of Applied Statistics
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• v.16 no.1
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• pp.87-100
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• 2003

Most of statistical data are generated by a set of dynamic, stochastic, and simultaneous relations. An important question is how to specify statistical models so that they are consistent with the dynamic feature of those data. A general hypothesis is that the lagged effect of a change in an explanatory variable is not felt all at once at a single point in time, but The impact is distributed over a number of future points in time. In other words, current control variables are determined by a function that can be reduced to a distributed lag function of past observations. It is possible to explain the relationship between variables in different points of time and to estimate the long-run impacts of a change in a variable on another if time lag series of explanatory variables are incorporated in the model specification. In this study, distributed lag structure is applied to the domestic stock market model to capture the dynamic response of the market by exogenous shocks. The Domestic market is found more responsive to the changes in foreign market factors both in the short and the long run.