• Communications for Statistical Applications and Methods
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• v.8 no.1
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• pp.159-171
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• 2001

Shapiro and Wilk (1972) developed a test for exponentiality with origin and scale unknown. The procedure consists of comparing the generalized least squares estimate of scale with the estimate of scale given by the sample variance. However the test statistic is inconsistent ; that is, the power of the test will not approach 1 as the sample size increases. Hence we give a test based on the ratio of two asymptotically efficient estimates of scale. We also have conducted a power study to compare the test procedures, using Monte Carlo samples from a wide range of alternatives. It is found that the suggested statistics have higher power for the alternatives with the coefficient of variation greater that or equal to 1.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.10a
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• pp.307-314
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• 2000

A parallel condensation algorithm for efficient dynamic analysis of three-dimensional large-scale structures is presented. The algorithm is developed for a user-friendly and cost effective high-performance computing system on a collection of Pentium processors connected via a 100 Mb/s Ethernet LAN. To harness the parallelism in the computing system effectively, a large-scale structure is partitioned into a number of substructures equal to the number of computers in the computing system Then, for reduction in the size of an eigenvalue problem the computations required for static condensation of each substructure is processed concurrently on each slave computer. The performance of th proposed parallel algorithm is demonstrated by applying to dynamic analysis of a three dimensional structure. The results show that how the parallel algorithm facilitates the efficient use of a small number of low-cost personal computers for dynamic analysis of large-scale structures.

• International Journal of Railway
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• v.1 no.2
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• pp.37-44
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• 2008

Safe, fast, efficient and effective railway is a main factor of economic development level of every country. This paper uses the DEA method to evaluate and compare the efficiency of 12 Regions of RAI. In addition, we introduce the reference(s) unit(s) for every inefficient region, and determine the amount of input decrease and/or output increase need to become them efficient. Findings indicate that in 2006, 4 regions of 12 are in Constant Return to Scale (CRS) status and 7 of them in Variable Return to Scale (VRS), and the average efficiency is 0.730 and 0.888, respectively. In other words, RAI works 27 percent under its capacity. More over results indicate that Hormozgan, Khorasan, Tehran and Isfahan Regions have the most efficiency respectively. The results show that the 8 regions, have been working in Increaser Return to Scale and 4 reminder Regions in Decrease Return to Scale. According to this results, we submit the suitable suggestion for improve the efficiency of the inefficient regions.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.2
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• pp.161-167
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• 2017

This paper measured and evaluated the technical efficiency, pure technical efficiency and scale efficiency of port labor via three inputs and three outputs using Data Envelopment Analysis (DEA). First, the average overall technical efficiency measured about 94.18 %, with 100 % pure technical efficiency being larger than 94.18% scale efficiency. As a result, 7 ports were identified as efficient, and 4 ports were identified as inefficient. Among the 4 ineffiecient ports, Donghae had the highest Increasing Return to Scale (IRS). However, the inefficient ports were all found to be less efficient in terms of resource operation than production scale. On the other hand, the efficient ports established priorities using the super efficiency method. As a result, port efficiency was highest for Incheon, Mokpo, Pyeongtaek-Dangjin, Masan, Yeosu Gwangyang, Jeju, and Gunsan-Daesan Ports, in order. In particular, Busan Port, found to be inefficient, would benefit from using Mokpo Port and Incheon Port as benchmarks to increase trade volume and modernize equipment for full-scale commercialization to improve labor efficiency.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.901-923
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• 2017

Efficient key distribution and management mechanisms as well as lightweight ciphers are the main pillar for establishing secure wireless sensor networks (WSN). Several symmetric based key distribution protocols are already proposed, but most of them are not scalable, yet vulnerable to a small number of compromised nodes. In this paper, we propose an efficient and scalable key management and distribution framework, named KMMR, for large scale WSNs. The KMMR contributions are three fold. First, it performs lightweight local processes orchestrated into upward and downward tiers. Second, it limits the impact of compromised nodes to only local links. Third, KMMR performs efficient secure node addition and revocation. The security analysis shows that KMMR withstands several known attacks. We implemented KMMR using the NesC language and experimented on Telosb motes. Performance evaluation using the TOSSIM simulator shows that KMMR is scalable, provides an excellent key connectivity and allows a good resilience, yet it ensures both forward and backward secrecy. For a WSN comprising 961 sensor nodes monitoring a 60 hectares agriculture field, KMMR requires around 2.5 seconds to distribute all necessary keys, and attains a key connectivity above 96% and a resilience approaching 100%. Quantitative comparisons to earlier work show that KMMR is more efficient in terms of computational complexity, required storage space and communication overhead.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1051-1056
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• 2009

Recently, there are many wide road in korea, so The Large scale cut slopes are increasing. Large scale cut slopes are better then small scale in case of construction and maintenance. General, Reinforced Slopes by Shotcrete are difficult to inspect because of stiff Slope and highly Working Area. So the Inspection Techniques are needed by the Non-contact and Non-destructive. On this Study, We are studying the method about efficient valuation and maintenance of Large scale Reinforced slopes by Shotcrete.

• Communications for Statistical Applications and Methods
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• v.9 no.3
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• pp.629-637
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• 2002

Shapiro and Wilk(1972) developed a test for exponentiality with origin and scale unknown. The procedure consists of comparing the generalized least squares estimate of scale with the estimate of scale given by the sample variance. However the test based on the statistic is inconsistent Kim(2001a) proposed a modified Shapiro-Wilk's test statistic using the ratio of two asymptotically efficient estimators of scale. In this paper, we study the consistency of the proposed test.

• Communications of the Korean Mathematical Society
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• v.18 no.3
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• pp.559-568
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• 2003

We introduce the notion of two-scale convergence for partial differential equations with random coefficients that gives a very efficient way of finding homogenized differential equations with random coefficients. For an application, we find the homogenized matrices for linear second order elliptic equations with random coefficients. We suggest a natural way of finding the two-scale limit of second order equations by considering the flux term.

• Communications for Statistical Applications and Methods
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• v.8 no.2
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• pp.473-481
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• 2001

Shapiro and Wilk (1972) developed a test for exponentiality with origin and scale unknown. The procedure consists of comparing the generalized least squares estimate of scale with the estimate of scale given by the sample variance. However the test statistic is inconsistent. Kim(2001) proposed a modified Shapiro-Wilk's test statistic based on the ratio of tow asymptotically efficient estimates of scale. In this paper, we study the asymptotic behavior of the statistic using the approximation of the quantile process by a sequence of Brownian bridges and represent the limit null distribution as an integral of a Brownian bridge.

• Journal of the Korea Society of Computer and Information
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• v.21 no.10
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• pp.157-166
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• 2016

The aims of this study are to contribute to efficient revenue management by analysis of the scale in elderly long-term care facilities. The data was used for input of the elderly long-term care costs Scale, and calculated the staffing standards and social welfare facilities workers with living wage guidelines in the Department of Health and Human Services. Revenue efficiency is the highest order of size are as follows. I8(98 people) \43,517,010, H6(86 people) \36,568,332, G8(78 people) \29,426,532, F8(68 people) \23,227,532, E8(58 people) \19,701,254, D8(48 people) \19,155,187, C6( 36) \14,389,109, B8(28 people) \9,920,031, A8(18 people) \3,721,031. It seems that its revenue efficiency even higher than the larger the scale. Meanwhile, The researchers focused on C6 (36 patients) model. Suggestion of this study are following; First, the arrangement can be provided based on needs of the elderly care facility staffing standards. Secondly, an elderly care facility selected wage guidelines. Thirdly, the elderly efficiency guidelines established by the size of a nursing facility. This study and other financial income factor are not the applicable limits.