• Journal of Korea Water Resources Association
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• v.54 no.5
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• pp.289-299
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• 2021

This study analyzes bifurcation characteristics of the Seolmacheon experimental catchment by extracting the shape variation of channel network due to variable scale of source basin or threshold area. As the area of source basin decreases, a bifurcation process of channel network occurs within the basin of interest, resulting in the elongation of channel network (increase of total channel length) as well as the expansion of channel network (increase of the source number). In the former case, the elongation of channel reaches overwhelms the generation of sources, whereas, in the latter case, the drainage path network tends to fulfill the inner space of the basin of interest reflecting the opposite trend. Therefore, scale invariance of natural channel network could be expressed to be a balanced geomorphologic feature between the elongation of channel network and the expansion of channel network due to decrease of source basin scale. The bifurcation structure of the Seolmacheon experimental catchment can be characterized by the coexistence of the elongation and scale invariance of channel network, and thus a further study is required to find out which factor is more crucial to rainfall transformation into runoff.

• Journal of the Korean Society for Library and Information Science
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• v.32 no.2
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• pp.143-167
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• 1998

This study is to evaluate whether economies of scale exist in four categories of university libraries in the Korea. Regression analysis is used to fit a log-log equation to the total budget-output (total circulation, interlibrary lending and borrowing, reference transactions, hours opened, volumes added, automation and information indicator) for all the types of libraries. In results of the analysis, returns to scale are almost constant in the national and public libraries and larger libraries. But there is presence of economics of scale in private libraries and all of the libraries. Except for hours opened, economies of scale decrease more rapidly.

• Journal of Korea Port Economic Association
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• v.22 no.3
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• pp.59-78
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• 2006

The purpose of this paper is to analyze the trend on scale efficiency of the Port of Gwangyang from 1994 to 2004 using CCR, BCC, and Malmquist index approaches. The main results are as follows. first, scale efficiency shows a 50% similar [5(94/95, 95/96, 97/98, 2001/2002, 2003/2004) out of 10] pattern to technical efficiency change. Second, total factor productivity increased at 48.57% rate of growth on average in 6 out of 10 periods except 96/97, 97/98, 99/2000, and 2000/2001. 2003/2004 period is the one period experiencing rapid total factor productivity changes, mainly due to technical progress. Third, the ranking order of accumulative indices is scale efficiency change, TFP change, efficiency change, technical change, and pure efficiency change. The main policy implication of this paper is that according to the CCR, BCC, and Malmquist results, the Port of Gwangyang should develop the plan for enhancing the 5 Malmquist indices with following the management way of benchmarking ports.

• Journal of the Korea Society of Computer and Information
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• v.27 no.3
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• pp.79-90
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• 2022

'Trust' is 'believing and relying on people or things', and at the same time, it is the foundation and essential condition of existence of a specific community or society. How blockchain technology creates trust can be found in the fact that it is a technology shared by all participants. As a shared technology, blockchain itself shows three characteristics: transparency, immutability, and availability. Because it is shared, it is transparent, and because it is shared, it is immutable, which is difficult to modify or delete. In addition, since it is shared, the entire system operates normally even if some failure occurs. The significance of trust created based on this blockchain technology can be summarized in three aspects as follows. The first is to understand the problem of trust in connection with technology. Second, understanding the relationship between information and trust begins to pay attention. Third, based on the expanded information processing capability, it is possible to establish a large-scale, concrete relationship without central mediation.

• The Journal of the Korea Contents Association
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• v.10 no.10
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• pp.456-463
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• 2010

This study measured the relative efficiency and productivity change of the Korean professional sport teams using DEA model and Malmquist Index for 2006-2009. The main results of this study can be summarized as follows. First, in case of efficiency of CCR for 2006-2009, the number of efficient professional sport teams(CCR value is one) are two(Daejeon Citizen, Incheon United), three(Daejeon Citizen, Incheon United, FC Seoul), two(Daejeon Citizen, Incheon United), three(Kyungnam FC, Incheon United, FC Seoul) respectively. Second, Malmquist Index representing productivity change for 2006-2009 are 1.035, 0.9658, 1.5331 for Kyungnam FC, 1.2514, 0.8948, 0.9056 for Daegu FC, 1.1768, 0.8620, 0.9722 for Daejeon Citizen, 0.9368, 1.2609, 0.7714 for Incheon United, 1.0000, 1.0000, 1.0000 for FC Seoul, respectively. This result will be used by inefficient professional sport teams to improve inefficiency.

• The Journal of the Korea Contents Association
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• v.13 no.1
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• pp.366-375
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• 2013

Recently, management of Newspaper developmet of the internet news, broadcasting and free newspapers escalated competition between newspaper companies and other media companies as well as competition among newapaper companies. This paper analyzes the efficiency of Korean Newapaper using DEA model. We evaluate the CCR-O, BCC-O efficiency, SE and RTS of 30 Newspaper. We also suggest the Newpaper which can be benchmarked based on analyzed information. The result shows that ten Nespaper whose values of CCR-O efficiency are 1, and Fourteen Nespaper whose values of BCC efficiency are 1. RTS indicates IRS of 1 firms, DRS of 16 firms and CRS of 13 firms. To variables on the effectiveness of newspaper publishing companies for the understanding and performance analysis.

• Environmental and Resource Economics Review
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• v.14 no.3
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• pp.595-626
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• 2005

The purpose of this paper is to estimate technical efficiency, scale efficiency, and environmental efficiency by income level of Korean farms, and analyze the factors to decide three efficiencies. Depending on the non-parametric methods, we estimate technical using inputs and outputs of total farms without assuming of goods or behavior of optimization. The average technical efficiency of total firms under constant return to scale and strong disposability is 0.437. The technical inefficiency was caused by 47.7% in pure technical inefficiency, 11.3% in scale failure, and 3.2% in environmental inefficiency. The number of firms under increasing return to scale occupied almost 70% and 27% of total firms respectively. Higher are income class, middle debt & long debt per asset, and N effluents per cultural land, higher technical efficiency. The increases of BOD discharges per cultural land and machines per cultural land deteriorate environmental efficiency.

• Journal of Korea Water Resources Association
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• v.50 no.11
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• pp.725-734
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• 2017

The main purpose of this study is to analyze runoff aggregation structure and energy expenditure pattern of Choyang creek basin within the framework of power law distribution. To this end geomorphologic factors of every point in the basin of interest, which define tractive force and stream power as well as drainage area, are extracted based on GIS, and their complementary cumulative distributions are graphically analyzed through fitting them to power law distribution. The results indicate that three distinct behavioral regimes are observed from the complementary cumulative distributions of three geomorphogic factors. Based on the parameter estimation of power law distribution by maximum likelihood drainage area and stream power can be judged as scale invariance factor without finite scale while tractive force as scale dependence factor with finite scale. Furthermore, it is judged that tractive force would not follow power law distribution because it shows limited complex system behaviors only within the small extent of scale. The exponent of power law distribution for drainage area obtained in this study by maximum likelihood is larger than the previous researches due to the difference of parameter estimation methodologies. And the exponent for stream power is smaller than the previous researches due to the scaling property of channel slope for the basin of interest.

• Journal of Labour Economics
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• v.24 no.3
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• pp.13-38
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• 2001

The question about whether a shorter workweek may increase employment has been a serious issue and been furiously debated among collective bargainers. The advocators recommend publicly that a reduction in standard working hours will provide benefits to the unemployed through the provision of new jobs, and also can improve the quality of life workers. The opponents argue that a shorter workweek will increase labor costs and induce firms to reduce their production levels, and consequently cut back their demand for labor. Although the debate is still continuing, considerable has been made toward achieving the goal workweek reduction. The analytical framework of this paper is a Putty-clay-model, in which the short-and long-term impacts of changes in working time on the employment associated with the interrelations of wages, prices, hourly labour productivity, the firm's labor demand, business cycle and economic growth etc. must be analyzed.

• Journal of the Korean Data and Information Science Society
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• v.26 no.1
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• pp.111-121
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• 2015

Until now, the operation of community welfare centers for people with disabilities has brought a positive or a generous awareness. Nevertheless, in order to obtain a wide range of welfare outcomes efficiently, the imperative step in rehabilitation researches is to determine whether reasonable and scientific services are being provided to people with disabilities in rehabilitation centers. The purpose of this study was to analyze efficiency and productivity of 176 community welfare centers for people with disabilities. As a result, average technical efficiency for community welfare centers for people with disabilities was 0.4488; pure technical efficiency and scale efficiency was 0.6040 and 0.7080, respectively. The major conclusions of this study were as follows. First, applying the technical efficiency analysis, DMU2, DMU3, DMU8, DMU9, DMU11, DMU13, DMU14 were shown above average. It seems to have a regard for political elements in accordance with the regional social and economic differences. Second, as a result of scale efficiency analysis, the inefficient community welfare centers for people with disabilities such as DMU1, DMU5, DMU12, DMU16 are required to improve the number of employees, revenue, facility area. Finally, this study is expected to be an effectiveness analysis and performance evaluation for the rehabilitation services.