• Communications for Statistical Applications and Methods
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• v.9 no.3
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• pp.649-663
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• 2002

We consider an unlimited fluid queueing model which has Fractional Brownian motion(FBM) as an input and a single server of constant service rate. By using the result of Duffield and O'Connell(6), we investigate the asymptotic tail-distribution of the stationary work-load. When there are multiple homogeneous FBM inputs, the workload distribution is similar to that of the queue with one FBM input; whereas for the heterogeneous sources the asymptotic work-load distributions is dominated by the source with the largest Hurst parameter.

• Analyses & Alternatives
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• v.3 no.1
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• pp.135-157
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• 2019

The linkages between asset prices and macroeconomic outcomes are long-standing issue to both economists and monetary authorities. This paper explores the impact of asset prices on output and price in China. It focuses on the impacts of asset prices on the low quantiles of GDP gap and high quantiles of price gaprespectively. The main findings are the following: the influence of stock price gap, stock returns, and money growth on the different quantile of GDP gap and price gap are noticeable different, and there are significant impacts on the left tail of GDP gap distribution and on the right tail of price gap distribution. This implies that the results coming from simple regression will underestimate the economic risk imposed by asset price volatility. Moreover, these results also provide the caveat that one should cautiously distinguish the meaning of asset price gap and asset price growth rate and use them, through their contents are similar in some sense. One implication for monetarypolicy is that authority should interpret the relationship between asset prices and macro-economy in wider perspectives, and make the policy decision taking the impacts of asset prices on the tails of economy.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2007.05a
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• pp.101-110
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• 2007

Current strategic trends in service distribution and software development in response to Web as a platform represent a paradoxical concurrent pursuit of 'economy of scale' and 'service'. From the software perspective, the major novel elements of the Web 2.0 era are Web as a platform and the emergence of long-tail service enabling web sites to function as an independent distribution channel. The current study analyzed the platform strategy for establishing a community of interactive developer and customers taking the issue of economy of scale into consideration. Software industry should face the new reality and utilize the open source community for cost minimization and securing customer base. Furthermore, Lego-style software development should be adopted for maintaining cost-competitiveness in customized software development.

• Journal of the Korea Safety Management & Science
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• v.13 no.1
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• pp.195-202
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• 2011

The study interprets each of three classification models based on Bath-Tub Failure Rate (BTFR), Extreme Value Distribution (EVD) and Conjugate Bayesian Distribution (CBD). The classification model based on BTFR is analyzed by three failure patterns of decreasing, constant, or increasing which utilize systematic management strategies for reliability of time. Distribution model based on BTFR is identified using individual factors for each of three corresponding cases. First, in case of using shape parameter, the distribution based on BTFR is analyzed with a factor of component or part number. In case of using scale parameter, the distribution model based on BTFR is analyzed with a factor of time precision. Meanwhile, in case of using location parameter, the distribution model based on BTFR is analyzed with a factor of guarantee time. The classification model based on EVD is assorted into long-tailed distribution, medium-tailed distribution, and short-tailed distribution by the length of right-tail in distribution, and depended on asymptotic reliability property which signifies skewness and kurtosis of distribution curve. Furthermore, the classification model based on CBD is relied upon conjugate distribution relations between prior function, likelihood function and posterior function for dimension reduction and easy tractability under the occasion of Bayesian posterior updating.

• Information Systems Review
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• v.24 no.2
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• pp.1-20
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• 2022

Researchers are making contradictory claims through the concept of superstars and long tails about how the development of IT technology affects demand distribution. Unlike previous studies that focused on changes in demand from a macro point of view, this study explored whether the relationship between a company's marketing activities and consumer response differs depending on the product location (i.e., superstar vs. long tail) from a micro point of view. Based on the marketing mix framework, hypotheses were developed based on the relevant literature. In the case of empirical analysis, 2,835 daily data from 63 Korean films were tested using the quantile regression method. As a result of the analysis, it was found that the influence of marketing mix factors on sales varies depending on the location of the product. Specifically, the appeal breadth of the film and the effect of owned media are enhanced in superstar products, and the effect of acquisition media in long-tail products is enhanced and the negative effects of competition are mitigated. Unlike previous studies that focused on macroscopic changes in demand distribution, this study suggested marketing activities suitable for practitioners through microscopic analysis.

• Korean Journal of Poultry Science
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• v.27 no.3
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• pp.255-258
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• 2000

This study was carried out to investigate the distribution and morphological properties of mast cells in the ileum of Korean pheasant. In the ileum mast cells were located in the lamina propria of mucoase. The cells were mainly oval with irregular cell surface occasionally spindle-like or triangular in shape. Some mast cells had one or more tail-like long cytoplasmic processes. All mast cells had many blue granules stained by toluidine blue in the cytoplasm.

• Journal of the Korean Magnetics Society
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• v.7 no.4
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• pp.186-190
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• 1997

We measured an anisotropy inhomogeniety and dispersion of rf sputterd permalloy thin films by TBP(Transverse Biased Permeability) measurement method. Angular distribution function had a shape similar to the Lorentzian distribution, but magnitude distribution function deviates from the sysmetric Lorentzian distribution because of long tail to the region of a high Hk value. With increasing film thickness, the angular and magnitude anisotropy dispersion increased. The increase of angular dispersion was due to both the increase of grain size and local anisotropy in thicker films.

• Journal of Forest and Environmental Science
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• v.8 no.1
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• pp.51-66
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• 1992

This study was carried out to investigate the micromorphology of vessel wall sculpture such as shape of perforation plate, perforation rim, steepness of perforation plate, occurrence of vestured pit, warty layer and ray-vessel pitting on 13 species of Fagaceae in Korea. The results were summarized as follows ; 1. In the species examined, all sample species except Fagus crenata var. multinervis have simple perforation plate. But Fagus crenata var. multinervis has simple and scalariform perforation plate (it was called to combination perforation plate) in a tree stem. 2. The shapes of perforation rim could be classified into five types; Type A without tail, Type B with small tail on both sides, Type C with long tail on both sides, Type D with tail only one side and Type E with the very short interval between perforations. Among five types, Type Band C have higer frequency of distribution than the others. 3. The steepness of perforation plate measured was about 20 degree on pore zone and 43 degree on outside parts of pore zone. 4. Species with vestured pit were Q. aliena, Q, dentata, Q. variabilis, Fagus crenata var. multinervis, Castanopsis cuspidata var sieboldii, Q. acuta, Q. stenophylla, and Q. glauca. But the extent of vesturing was very slight and vestured pits were observed mainly in ray-vessel pit of some vessel elements. 5. Species with warty layer on the inner surface wall of all vessel elements were Q. acuta, Q. stenophylla, Q. glauca, Fagus crenata var. multinervis and species with warty layer of some vessel elements were Q. aliena, Q, dentata, Q. variabilis, Castanopsis cuspidata var. sieboldii. 6. Species with palisade ray-vessel pit were Q. acuta, Q. stenophylla, Q. glauca, Castanea crenata, Castanea bungeana, Q. aliena, Q. serrata, Q. mongolica, and species with scalariform ray-vessel pit was Fagus crenata var. multinervis and species with oval ray-vessel pit were Q, dentata, Castanopsis cuspidata var sieboldii.

• 한국경영정보학회:학술대회논문집
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• 2008.06a
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• pp.1023-1028
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• 2008

Recently the advent of web 2.0 era is an important trend in the business environmental change. Web 2.0 era means users' active participation, share, and openness, develop 'Internet penetration into everyday life,' and change many aspects of our society. web 2.0 has been making these following changes in the socioeconomic aspects: 1) acceleration of system shift to a small quantity of multi-species production system 2) growing influence of on-line channel/information to consumers 3) various minorities' power increase in the socioeconomic sector. Web 2.0 has been making these following changes in the firms' strategies for information management: 1) increase of external knowledge and information utilization 2) amplification and reproduction of information from customers 3) change of information distribution: pursuit of two-way communication with customers 4) integration of different information/services for business transformation. Firms must squarely look at socioeconomic changes owing to web 2.0, and utilize them for firms' effective information management.

• Wind and Structures
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• v.2 no.2
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• pp.85-94
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• 1999

The EARPG(1)/UPS was first developed by Seong (1993) and has been tested for wind pressure time series simulations (Seong and Peterka 1993, 1997, 1998) to prove its excellent performance for generating non-Gaussian time series, in particular, with large amplitude sharp peaks. This paper presents a parametric study focused on simulation of extreme value statistics based on the synthetic realizations of the EARPG(1)/UPS. The method is shown to have a great capability to simulate a wide range of non-Gaussian statistic values and extreme value statistics with exact target sample power spectrum. The variation of skewed long tail in PDF and extreme value distribution are illustrated as function of relevant parameters.