• The Journal of the Korea Contents Association
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• v.12 no.7
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• pp.284-294
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• 2012

In the study, we estimate efficiencies using CCR model of DEA, Super efficiency(AP) model, and super-SBM model with the data of 32 regional public hospitals in Korea from 205 to 2009. With Wilcoxon-Mann-Whitney statistics, we analyze efficiency differences for environmental factors(regions, type of hospital, type of operations, type of education training, relative importance of madicaids) among regional public hospitals. The results can be summarized as follows. Firstly, technical inefficiencies of regional public hospitals range from 15% to 17% in CCR model, 13% to 15% in AP model, 7% to 12.6% in SuperSBM model. Second, we confirm that environmental factors of hospitals cause different inefficiencies among them. The implication of this study is that policy and institutional change may need to improve the efficiencies along with internal managerial reform.

• 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.

• Journal of Ocean Engineering and Technology
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• v.27 no.1
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• pp.109-114
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• 2013

Regulations on exhaust emissions for vehicles and ships are reinforced. Therefore, researchers are focus on developing an excellent engine that emits less environmental pollutants and leads to high gas milage. The purpose of this study is to investigate the efficiency of intake super charging system. Super charger is the special device for improving performance of intake system. Futhermore, for reducing exhaust emissions, the examine are performed on the effectiveness of device structures that tow materials for performance improvement. To fulfill the purpose, Super charger materials of aluminum alloy(AL6262) and polycarbonate were selected and then their temperature change of super charger and inhalation efficiency were analyzed by ANSYS program. In addition, it is attempted to apply these results to device development by comparing the results with the real value. As a result, there was less temperature change of super charger in aluminum materials than polycarbonate, and HC and NOx were decreased when the super charger was installed.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.2
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• pp.138-150
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• 2000

This study is concerned with computerized multi-level substructuring methods and stress analysis of coil springs. The purpose of substructuring methods is to reduce computing time and capacity of computer memory by multiple level reduction of the degrees of freedom in large size problems which are modeled by three dimensional continuum finite elements. In this paper, a super element has been developed for stress analysis of coil springs. The spring super element developed has been examined with tension and torsion simulation of cylindrical bars for demonstrating its validity. The result shows that the super element enhances the computing efficiency while it does not affect the accuracy of the results and it is ready for application to the coil spring analysis.

• Journal of Korean Society for Quality Management
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• v.35 no.3
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• pp.21-36
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• 2007

This article is to analyze the service efficiency of public sector using Data Envelopment Analysis(DEA). We tried to measure the public service quality and overall satisfaction by using several DEA models, degree of combination and top2box which is a little bit different methodology from traditional ones. We used CCR, Super-efficiency and Slack based measure(SBM) model in DEA to measure public service efficiency of the 16 public institutions(7 City Halls and 9 Provincial offices). Since the traditional method based on the measurement model(CCR, BCC) has the fundamental problems without taking account of the existence of slacks inputs and outputs in several efficient units, we suggest to measure the exact amount of efficiency and inefficiency of the public sector and rank analysis many efficient units exactly through the slacks-based measure model(SBM)

• Structural Engineering and Mechanics
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• v.10 no.6
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• pp.603-619
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• 2000

Analysis of a framed structure for vertical vibration requires a lot of computational efforts because large number of degrees of freedom are generally involved in the dynamic responses. This paper presents an efficient modeling technique for vertical vibration utilizing substructuring technique and super elements. To simplify the modeling procedure each floor in a structure is modeled as a substructure. Only the vertical translational degrees of freedom are selected as master degrees of freedom in the inside of each substructure. At the substructure-column interface, horizontal and rotational degrees of freedom are also included considering the compatibility condition of slabs and columns. For further simplification, the repeated parts in a substructure are modeled as super elements, which reduces computation time required for the construction of system matrices in a substructure. Finally, the Guyan reduction technique is applied to enhance the efficiency of dynamic analysis. In numerical examples, the efficiency and accuracy of the proposed method are demonstrated by comparing the response time histories and the analysis time.

• Journal of Digital Convergence
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• v.12 no.6
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• pp.181-192
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• 2014

This study suggests consulting directions for non-profit private organizations which were found to be inefficient in the efficiency analysis for the public activities support projects on those organizations performed by the Korean government. An ANOVA analysis on seven types of public activities support projects showed that there were differences among those types. By applying CCB-I, BCC-I, Super efficiency models among DEA, performance efficiencies were analyzed. Four input elements (age of the organization, supported amount, number of members, and the number of workers) and three output elements (project scores, financial scores, and comprehensive scores) were analyzed, and high efficient organizations were found as benchmarking objects, and, through super efficiency analysis, those objects were classified into short, mid, and long-term objects. Through such methods, this research provided organizations with the best information on other organizations to learn from and improve themselves.

• Management & Information Systems Review
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• v.31 no.1
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• pp.273-292
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• 2012

This paper attempts to analyze the efficiency of Korean Materials and Components Industry. 48 sample companies are extracted and efficiency analysis for them are accomplished by using DEA model. We use both CCR-I model and BCC-I model and classify the 48 companies into two groups; efficient and inefficient companies. We find the reference set which inefficient companies should benchmark in order to achieve efficiency and present the improving values for input and output variables. We analyze whether the inefficiencies come from scale or inefficient operation by measuring the scale efficiency. Finally the ranking among the efficient companies is derived through the super-efficiency analysis.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.198-200
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• 2022

With the expansion of the global supply chain, the efficiency of maritime logistics is considered a crucial factor for countries' trade and competitiveness. Nevertheless, prior research has not thoroughly evaluated the efficiency of maritime logistics, including countries' ports and shipping capacities. Accordingly, this study examines integrated maritime logistics efficiency at the national level using DEA-CCR, BCC, and super-efficiency DEA. Furthermore, this study identifies a difference between the selected countries' maritime logistics efficiency and LPI (Logistics Performance Index) through Spearman's correlation test as an ad-hoc analysis. From this, Asian countries showed higher efficiency and European countries showed higher LPI scores. These results might be derived from this difference in port-city development patterns. Additionally, the main cause of inefficiency in Europe and Japan might be attributed to high fleet capacity of control. Consequently, this study can provide valuable implications for coastal countries to set more efficient directions for maritime logistics investment and policy.

• Journal of Digital Convergence
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• v.16 no.6
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• pp.75-84
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• 2018

Although many logistics companies are interested in project logistics, the existing research has been limited to the growth potential of project logistics market and the high barrier and importance of project logistics. This study analyzes using DEA the operational efficiency of forwarding companies registered in major overseas construction EPC companies and performing logistics services for overseas plant construction projects. For efficiency analysis, Super-SBM analysis and Malmquist analysis are used among DEA analysis techniques. As a result of the Super-SBM analysis, DMU 5 ranked first at 1.807. DMU 5 is more efficient than the other large corporations because it has the stable supply of its parent company H and the smallest input and output variables among the large corporations. As a result of Malmquist analysis, TCI, which is a technological development, showed a fluctuation while TECI showed a relatively stable variation. In addition, there is a difference in scale between major companies and small and medium sized companies. So, it is necessary to identify the efficiency improvement strategy for each group and apply it to the practical work.