• The Journal of Information Technology
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• v.10 no.2
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• pp.47-64
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• 2007

Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. Accurate predictions of software release times, and estimation of the reliability and availability of a software product require quantification of a critical element of the software testing process : test coverage. This model called enhanced non-homogeneous poission process(ENHPP). In this paper, exponential coverage and S-coverage model was reviewed, proposes the exponentiated exponential coverage reliability model, which maked out efficiency substituted for gamma and Weibull model(2 parameter shape illustrated by Gupta and Kundu(2001). In this analysis of software failure data, algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE statistics for the sake of efficient model, was employed.

• International Journal of Reliability and Applications
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• v.7 no.2
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• pp.155-166
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• 2006

Many software reliability growth models (SRGMs) based on nonhomogeneous Poisson process (NHPP) have been developed and applied in practice. NHPP SRGMs are characterized by their mean value functions. Mean value functions are usually derived from differential equations representing the fault detection/removal process during testing. In this paper such differential equations are regarded as frameworks for generating mean value functions. Currently available frameworks are theoretically discussed with respect to capability of representing the fault detection/removal process. Then two general frameworks are proposed.

• Journal of the Korean Society of Industry Convergence
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• v.6 no.3
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• pp.201-205
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• 2003

The effects of adsorption and desorption of alkali-metals on Si(111) surface were investigated by using AES and RHEED-system. The adsorption system is a fundamental interest because of its unique electronic properties such as measurement of work function change, adatom-core level shift. It was found that the growth node of K on Si(111) surface was layer by layer growth and the saturation coverage was 2.0ML at room temperature. Superstructure changes on Si(111) surface according to the alkali-metal thickness and substrate temperatures were accurately defined. By applying the isothermal desorption method, the desorption energies of Li/Si(111) and K/Si(111) surfaces was measured. On Li/Si(111) and K/Si(111) surfaces, the desorption energies were 3.07 eV, 2.19 eV respectively.

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.33-42
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• 2007

Accurate predictions of software release times, and estimation of the reliability and availability of a software product require quantification of a critical element of the software testing process : test coverage. This model called Enhanced non-homogeneous poission process(ENHPP). In this paper, exponential coverage and S-shaped model was reviewed, proposes the Kappa coverage model, which maked out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE statistics and Kolmogorov distance, for the sake of efficient model, was employed. From the analysis of mission time, the result of this comparative study shows the excellent performance of Burr coverage model rather than exponential coverage and S-shaped model using NTDS data. This analysis of failure data compared with the Kappa coverage model and the existing model(using arithmetic and Laplace trend tests, bias tests) is presented.

• Journal of the Korea Society of Computer and Information
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• v.12 no.6
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• pp.89-96
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• 2007

Finite failure NHPP models presented in the literature exhibit either constant. monotonic increasing or monotonic decreasing failure occurrence rates per fault. Accurate predictions of software release times. and estimation of the reliability and availability of a software product require quality of a critical element of the software testing process : test coverage. This model called Enhanced non-homogeneous Poission process(ENHPP). In this paper, exponential coverage and S-type model was reviewed, proposes modified(the superosition and mixture) model, which make out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method. model selection based on SSE statistics for the sake of efficient model, was employed.

• Convergence Security Journal
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• v.7 no.3
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• pp.7-13
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• 2007

Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. Accurate predictions of software release times, and estimation of the reliability and availability of a software product require quantification of a critical element of the software testing process : test coverage. This model called Enhanced non-homogeneous poission process (ENHPP). In this paper, exponential coverage and S-shaped model was reviewed, proposes the superposition model, which maked out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE statistics for the sake of efficient model, was employed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.12
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• pp.2311-2318
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• 2007

Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. Accurate predictions of software release times, and estimation of the reliability and availability of a software product require Release times of a critical element of the software testing process : test coverage. This model called Enhanced non-homogeneous Poission process(ENHPP). In this paper, exponential coverage and S-shaped model was reviewed, proposes the Kappa coverage model, which make out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE statistics and Kolmogorov distance, for the sake of efficient model, was employed. Numerical examples using real data set for the sake of proposing Kappa coverage model was employed. This analysis of failure data compared with the Kappaa coverage model and the existing model(using arithmetic and Laplace trend tests, bias tests) is presented.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.53.2-53.2
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• 2021

Quasar luminosity function (QLF) shows the active galactic nucleus (AGN) demography as a result of the combination of the growth and the evolution of black holes, galaxies, and dark matter halos along the cosmic time. The recent wide and deep surveys have improved the census of high-redshift quasars, making it possible to construct reliable ultraviolet (UV) QLFs at 2 < z < 6 down to M1450 = -23 mag. By parameterizing these up-to-date observed UV QLFs that are the most extensive in both luminosity and survey area coverage at a given redshift, we show that the UV QLF has a universal shape, and their evolution can be approximated by a pure density evolution (PDE). In order to explain the observed QLF, we construct a model QLF employing the halo mass function, a number of empirical scaling relations, and the Eddington ratio distribution. We also include the outshining of AGN over its host galaxy, which made it possible to reproduce a moderately flat shape of the faint end of the observed QLF (slope of ~ -1.1). This model successfully explains the observed PDE behavior of UV QLF at z > 2, meaning that the QLF evolution at high redshift can be understood under the framework of halo mass function evolution. The importance of the outshining effect in our model also implies that there could be a hidden population of faint AGNs (M1450 > -24 mag), which are buried under their host galaxy light.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.194-206
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• 1998

In 1977, Local governments' planting regulations for the development projects were established in accordance with the revised building law in Korea. A landscaped area, planting densities of trees and shrubs, a percentage of evergreen plants, minimum tree size and species were prescribed in the planting regulations. But the clauses for an excessive planting density and a high ratio of evergreen trees that the regulations includes, have been gradually in the way to a creative planting design, and raise a problem of poor growth of trees an a disordered planting landscape. Therefore, in this study the present planting regulations of 124 local governments throughout the country were analyzed and compared with 13 foreign local governments' of 4 countries ; Japan, the United States of America, Canada and Singapore. And the linitations and characteristics of the regulations are drawn as follows ; 1. The regulations focus on controlling the green spaces and plantings by quantitative methods such as controlling the number of trees and the landscaped area, which are inadequate for estimating the crown coverage of mature trees, and which areinadequate for estimating the crown coverage of mature trees, and implementing the function of polantings and the use of green spaces. 2. Minimums of tree densities are higher than those of foreign countries, especially higher about 10 times to 100 times than those of the United States of America. 3.Excessive number of evergreen trees and fruit trees should be planted under the present planting regulations, that results in constricting the creativity in planting design. 4. An article for using specific tree size, 2.0ms over in height makes it difficult to use a wide variety of different sizes of trees. And there is no incentive measures when larger trees are planted. To enhance the quality of green spaces and plantings, it is needed that the function and locating of green spaces and plantings have to be emphasized, and the planting density should be concerned about the mature tree size. The incentive measure to use various sizes of trees is also needed, and the regulations to use excessive number of evergreen trees or fruit trees should be loosened.

• The Journal of the Korean life insurance medical association
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• v.24
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• pp.97-117
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• 2005

Internally Korean insurance market is that whole life products' growth are becoming slowdown that's why new insurance products have appeared on the market in consideration of consumer's needs recently. Externally domestic insurance market competitions has drifted from insurance industry to whole financial industry since bankasurance started. Life insurance companies should open up a new market to survive from severe competitions. Worksite marketing can be an alternative. An insurer make arrangements with an employer about an insurance terms which an insurer offers in Worksite marketing. Then eligible individuals enroll in the plans at their own discretion and pay 100 percent of the premium for coverage through payroll deductions. An employer doesn't need to pay extra money for additional benefit but can raise employee's loyalty and satisfaction of company through worksite marketing. An employee can be covered at discounted premium rate and less strict underwriting guidelines to an insurer compared to individual insurance. In developed countries specially U.S insurance market, Worksite marketing is getting very popular and growing rapidly due to the advantages. Worksite marketing has both individual insurance characters and group insurance characters. Individual insurance characters are that employees enroll in the plans at their own discretion and pay 100 percent of the premium for coverage. Group insurance characters are that actively at work and participation etc. An insurer have to reflect these two characters on Worksite marketing when an insurance company work out a plan for developing products and underwriting guidelines. When an insurer devise worksite products, one should consider participation level which means percentage of eligible employees participating. Participation is related to anti-selection. As we know underwriting is essential for every kind of insurance, especially underwriting plays major role in worksite marketing. We can see that in the below. Firstly, it has a function in calculation of premium rate. When calculate premium rate for worksite products underwriters have to estimate expected participation level and risk factors. So underwriters and acturies keep in close contact with each other. Secondly, underwriting methods are important. When an insurer underwrite worksite products, there are three kinds of underwriting methods. These are Simplified issue underwriting, Full underwriting and Guaranteed issue underwriting. Simplified issue underwriting typically requires no medical examination, but usually requires supplying satisfactory answers to one or several health and/or lifestyle questions. Full underwriting requires a complete medical history questionnaire that may further require an exam. Guaranteed issue underwriting means that coverage is issued without the employee having to provide evidence of insurability. When insurer set the GI limit are usually based on the type of industry, number of eligible employees, the average amount of coverage and participation level. In addition to insurer should have a clear definition of eligible employee on the insurance provision and application form. It will minimize possibility of trouble claims and anti-selection. An insurer also establish preexisting condition exclusion and special guidelines for late entrants. When an insurer introduce Worksite marketing to Korean insurance market, an insurer has to examine market research to analyze potential market and strategy of sales most of all. Also an insurer should review real situation of the U.S, England and Japanese market etc. There are a lot of new technologies about worksite marketing process that an insurer should learn. When an insurer consider many things which we explained it can be a real alternative.