• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.5
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• pp.1807-1824
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• 2015

As the technologies advance, mobile peer-to-peer (MP2P) networks or systems become one of the major ways to share resources and information. On such a system, the information retrieval (IR), including the development of scalable infrastructures for indexing, becomes more complicated due to a huge increase on the amount of information and rapid information change. To keep the systems on MP2P networks more reliable and consistent, the index structures need to be updated frequently. For a semantic IR system, the index structure is even more complicated than a classic IR system and generally has higher update cost. The most well-known indexing technique used in semantic IR systems is Latent Semantic Indexing (LSI), of which the index structure is generated by singular value decomposition (SVD). Although LSI performs well, updating the index structure is not easy and time consuming. In an MP2P environment, which is fully distributed and dynamic, the update becomes more challenging. In this work, we consider how to update the sematic index generated by LSI and keep the index consistent in the whole MP2P network. The proposed Concept Space Update (CSU) protocol, based on distributed 2-Phase locking strategy, can effectively achieve the objectives in terms of two measurements: coverage speed and update cost. Using the proposed effective synchronization mechanism with the efficient updates on the SVD, re-computing the whole index on the P2P overlay can be avoided and the consistency can be achieved. Simulated experiments are also performed to validate our analysis on the proposed CSU protocol. The experimental results indicate that CSU is effective on updating the concept space with LSI/SVD index structure in MP2P semantic IR systems.

• Journal of KIISE:Databases
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• v.31 no.6
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• pp.624-640
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• 2004

Recently, with the rapid development of location-based techniques, index structures to efficiently manage moving objects have been required. In this paper, we propose a new spatio-temporal index structure that supports a future position retrieval and minimizes a update cost. The proposed index structure combines an assistant index structure that directly accesses current positions of moving objects with KDB-tree that is a space partitioning access method. The internal node in our proposed index structure keeps time parameters in order to support the future position retrieval and to minimize a update cost. Moreover, we propose new update and split methods to maximize the space utilization and the search performance. We perform various experiments to show that our proposed index structure outperforms the existing index structure.

• International Journal of Quality Innovation
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• v.7 no.3
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• pp.1-14
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• 2006

Economic value added (EVA) is introduced on two levels: as index for evaluation of corporation and as index for evaluation of business unit. In the latter case, application of one and the same cost of capital to all business units of a business corporation may be possible, but it is a fundamental policy for EVA to apply different cost of capital to business units with different risks. Estimate of cost of capital of business units is a problem to be resolved. The author, focusing on the question of the estimate of cost of capital of business units, has conducted a demonstrative study on risk structure of cost of capital estimates by using financial indices of Japanese manufacturers (37 automotive industries, 141 electrical and electronic machinery industries, 63 food processing industries, 98 chemical industries, 125 general machinery industries) for a period of 5 years from 1995 to 1999. The author presumes that $\beta$ is explained by a regression formula ${\beta}=B_0+{\Sigma}B_iY_i+{\alpha}$ ($Y_i$: financial indices) and selects 40 explanatory variables from financial statements as risk components. Using their financial indices, the author concludes through a series of statistical analyses that there is a good likelihood of estimating cost of capital for Japanese industries and is convinced that it will lead to more reliable and practical results by assigning averages and variances to 40 primary financial indices for a period of 3 to 5 years selected in this demonstrative study.

• Health Policy and Management
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• v.30 no.3
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• pp.418-429
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• 2020

Background: This study aims to analyze the cost and the length of stay (LOS) of acute myocardial infarction (AMI) patients with coronary artery stenting according to the characteristics of individuals and institutions. Methods: The data was collected from Korean National Health Insurance Service's customized database in 2010 and 2015. Chi-square test, t-test, analysis of variance, and multilevel analysis were performed. Results: The intraclass correlation coefficients for cost were 7.02% in 2010, 5.61% in 2015 and for LOS were 3.17%, 1.40%, respectively. The average costs were 9,067,000 won in 2010 and 9,889,000 won in 2015 (p<0.0001). However, the cost in 2015 was lower than the cost applying increased fee. The costs increased in aged 50-59 years, 60-69 years, and aged ≥70 years versus in aged under 49 years. The cost was higher in Charlson comorbidity index (CCI) 3 to 4 and ≥5 than in CCI 0. The costs were lower in male, medical aid recipients, metropolises, and local hospitals in other regions in 2010. LOS decreased from 8.1 days in 2010 to 7.4 days in 2015. It decreased in male, high income group, and the group of admission via emergency room. However, it increased in higher ages and medical aid recipients, and it also increased when CCI rose. The Internal Herfindahl Index was related to LOS in 2010. Conclusion: The variation of hospital level was small compared to the patient level. Therefore, it is important to implement applicable policies at the patient level in order to reduce cost and LOS of AMI patients.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.103-112
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• 2017

PURPOSES : In this study, field performance evaluation of crack treatment of pavement and the feasibility of surface treatment of pavement are presented. The performance and cost of preventive maintenance methods have been previously verified, and the methods are being used in many developed countries and cities. However, the performance and cost of the system have not been verified in domestic, field applications. Therefore, in order to improve performance, the field performance is evaluated, and a reasonable cost is proposed. METHODS : Visual Inspection was conducted to evaluate the field application and performance of the preventive maintenance method. In addition, the PCI index was calculated from the results of visual inspection of the application area of the surface treatment method, and the performance life of each method was predicted. For the economic evaluation, life cycle cost analysis was performed using the life cycle cost analysis program. RESULTS :In order to evaluate and quantify the field performance of crack repair material, the residue condition of the pavement surface after crack treatment, rather than the performance of the material, is evaluated. In addition, the crack resistance and performance life of surface treatment methods are evaluated. The cost of currently available treatment methods are compared to the common pavement cut and overlay method, and it is determined that the preventive method is not economical based on life cycle cost analysis. CONCLUSIONS :Because of the characteristics of cracking, it is necessary to conduct the evaluation of currently applied methods and the analysis of the cause of damage, by visual inspection. Moreover, in order to evaluate the performance and economic suitability of the currently applied surface treatment methods, it is necessary to acquire information on application sections by monitoring their long-term conditions and performance.

• Journal of the Korea Institute of Building Construction
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• v.14 no.5
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• pp.415-422
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• 2014

There is growing difference between a planned value and an actual cost for increasing as an risk of construction cost. A construction cost index is an alternative to redeem a problem, but it is still very difficult to reduce an actual differential as a price fluctuation. Furthermore an existing theory of a construction cost index is overly complex, and is unsuitable for using in working-level. This study suggests an optimum correction rate in respect of a total construction cost. It is analyzing the actual cost of 53 public buildings that the Public Procurement Service ordered. The objects are main processes that include architectural works, mechanical works, electrical works, telecommunication works, and service facilities. It is compared a total construction cost based on absolute error rate using the median from frequentist principle. For this, it is selected the suitable regression model and set a correction rate.

• Journal of Korea Spatial Information System Society
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• v.7 no.3 s.15
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• pp.119-130
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• 2005

A spatial data warehouse is a system that stores geographical information as a subject oriented, integrated, time-variant, non-volatile collection for efficiently supporting decision. This system consists of a builder and a spatial data warehouse server. A spatial data warehouse server suspends user services, stores transferred data in the data repository and constructs index using stored data for short response time. Existing methods that construct index are bulk-insertion and index transfer methods. The Bulk-insertion method has high clustering cost for constructing index and searching cost. The Index transfer method has improper for the index reconstruction method of a spatial data warehouse where periodic source data are inserted. In this paper, the efficient index reconstruction method using a partial index in a spatial data warehouse is proposed. This method is an efficient reconstruction method that transfers a partial index and stores a partial index with expecting physical location. This method clusters a spatial data making it suitable to construct index and change treated clusters to a partial index and transfers pages that store a partial index. A spatial data warehouse server reserves sequent physical space of a disk and stores a partial index in the reserved space. Through inserting a partial index into constructed index in a spatial data warehouse server, searching, splitting, remodifing costs are reduced to the minimum.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.111-112
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• 2012

Korean government is planning to supply a half million public and permanent rental houses from 2013 to 2018 for settlement of non-homeowners. It is requested an objective criterion to appropriate the budget for the rental houses construction project cost. In this study, construction cost indices, which reflect the inflation trend of construction resources, were explorated to suggest a effective methodology for the construction cost estimation of therental houses. We figured out the future construction cost indices using several scientific methods, and seven estimated indices values were shown. It is required an additional research to select the proper value among the analyzed indices.

• KIEE International Transactions on Power Engineering
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• v.5A no.3
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• pp.286-292
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• 2005

As the power industry moves towards open competition, there has been a call for methodology to evaluate power system reliability by using composite interruption cost. This paper presents algorithms to evaluate the interruption cost of distribution power systems by taking into consideration the failure source and the composite customer interruption cost. From the consumer's standpoint, the composite customer interruption cost is considered as the most valuable index to estimate the reliability of a power distribution system. This paper presents new algorithms that consider the load by customer type and failure probability by distribution facilities while calculating the amount of unserved energy by customer type. Finally, evaluation results of unserved energy and system interruption cost based on composite customer interruption cost are shown in detail.

• Journal of agriculture & life science
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• v.43 no.4
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• pp.45-51
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• 2009

Production cost in agricultural accounting has been utilized as an index for determining appropriate prices of agricultural products, establishing agricultural policies and providing extension services for farmers. However, it is necessary for the concept of cost accounting to introduce in establishing farm planning and consulting farmers' management. In this paper, I review problems associated with costing rules which are considered as criterion for accounting cost in agriculture and suggest directions for cost accounting in agricultural management.