• Progress in Superconductivity and Cryogenics
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• v.10 no.2
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• pp.34-37
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• 2008

According to the recent design of an HTS (High Temperature Superconducting) power transformer whose capacity is hundreds MVA, the rated current values of the low voltage side are generally over thousands amps. Considering the performance of the recent HTS wires, it is inevitable to use several HTS wires in parallel for large rated current. Lots of stacked HTS wires were fabricated and tested so far, and the results have showed that we have to transpose each wire in order to reduce the AC losses as well as to increase the current capacity. But many development programs about HTS transformers reveal that the transposition of the several wires during the winding process is quite difficult not only in case of the layer windings but also in case of the pancake type ones. So, we need transposed multiple HTS wire which we can handle like single wire or cable for the HTS windings of large capacity power transformer. We fabricated several kinds of samples of multiple HTS wire with transposition to apply it to the HTS windings of power transformer. The electrical characteristics such as critical currents or AC losses are analyzed by experiments in case by case. Finally we present the best design of a multiple HTS wire for power transformer.

• The Journal of Fisheries Business Administration
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• v.37 no.1 s.70
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• pp.1-24
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• 2006

Reducing fishing capacity is one of current issues in the international fisheries. This is because that increased fishing capacity has caused not only fish stocks to be depleted, but also additional fishing costs to be incurred, which resulted in reduction of economically viability of fisheries. For this reason, FAO adopted the International Plan of Action for the Management of Fishing Capacity' in 1999 and recommended member countries to estimate fishing capacity and to implement the policy to reduce fishing capacity. This study is aimed to measure fishing capacity of the Large Purse Seines Fishery that is one of offshore fisheries in Korea using both Peak - to - Peak Analysis and Data Envelopment Analysis in order to provide a policy information for preparation of domestic plan of action for the management of fishing capacity. The results of PTP Analysis were almost similar to those of DEA Analysis. The DEA results showed that the capacity utilization in 2004 was about 75%, it was obvious the capacity did not utilize enough. The sensitivity analysis on DEA results indicated that 24% of the number of ships, 26% of the tonnages, or 29% of the horse powers should be reduced if the present catch remained. In addition, if the catch remains at the MSY base level of large purse seines, the analysis suggested that the number of ships, tonnages and horse powers should be reduced by 15%, 18%, and 21% respectively.

• International Journal of Highway Engineering
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• v.17 no.5
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• pp.123-133
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• 2015

PURPOSES : This study aimed to develop a new highway capacity estimation method and provide comparative results among traditional capacity estimation methods and the recommended values in the latest version of KHCM. METHODS : The limitations of the existing methods, such as inconsistency and underestimation of the capacity value, are summarized through an extensive literature review. To overcome these limitations, a new method is introduced by adopting a definition of capacity and traffic flow characteristics at or near breakdown points. This method can produce the capacity value by searching a point corresponding to the maximum traffic flow through analysis of gradient changes (point of inflection) of the traffic flow and speed distribution. Comparative results of capacity values from each method are also presented to validate the new method by using data collected from detectors on freeways. RESULTS: From the analysis results, it is shown that a consistent capacity value can be estimated by applying the new method. In addition, the resulting capacity values are 3%-4% higher than those recommended in KHCM. CONCLUSIONS : The capacity values listed in the current KHCM tend to produce underestimated results. The new method presented in this paper may be included in the future edition of KHCM.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2000.02a
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• pp.29-32
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• 2000

Superconducting transmission cable is one of interesting part in power application using high temperature super-conducting wire as transformance. One important parameter in HTS cable design is transport current distribution because it is related with current transmission capacity and loss. In this paper, we present the calculation theory of current distribution for multi-layer cable using the electric circuit model and in example, calculation results of current distribution and AC loss in each layer of 4-layer HTS transmission cable.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.6
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• pp.606-611
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• 2013

In this study, the regional states of 7 items are analyzed, the regional risks are calculated by using normalized data & analysis hierarchy process to set regional oil recovery capacity. Area on-water oil recovery capacity, $7,500k{\ell}$, is separated and regional on-water oil recovery capacity is determined, based on calculated regional degree of risk. Excessive current oil recovery capacities, setting in Incheon, Gunsan, Mokpo, Busan region, are as a result distributed to the other regions in each area. In case of central region, Daesan is increased as much as $1,475k{\ell}$, Yeosu is increased as much as $375k{\ell}$, Ulsan is increased as much as $475k{\ell}$. The regional on-water oil recovery capacity, considering both the cause of accident aspects and marine environmental & economic aspects, is estimated as more balanced distribution model, compared to current standard of on-water oil recovery capacity.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.331-334
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• 2005

Three RC beams are fabricated and tested to assess the ultimate load-carrying capacity. Depending on the crackings, the flexural stiffness of the RC beams are changed. However, these variations of the flexural stiffness do not influenced on the ultimate load-carrying capacity of the tested beams. Based on the behaviors of RC beams, the validation of the current assessment codes to discussed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.1
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• pp.22-28
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• 2018

In case of developing a combined system by a number of distributed resources with storage device, a number of application suggests a huge capacity can derive operational flexibility both power supply issues or when unexpected situation imposed. However, it is important to determine a resonable energy capacity because the device have many controversial cost issues in current power system industry. An ESS application which focusing essentially required points can induce appropriate storage capacity that required in economic operation. In this paper, a curtailment supporting algorithm based on storage device is introduced, and applied in the capacity calculation method. The main algorithm pursues handling minor exceeding quantities which can cause mechanical load at blade; This paper tries to include it for configuring hybrid algorithm with pitch control. Several fluctuating conditions are utilized in simulation to reflect critical situation. The analyzing process focuses on the control feasibility with applied capacity and control method.

• East Asian mathematical journal
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• v.34 no.2
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• pp.127-154
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• 2018

In the 2015 revised curriculum, "creative and convergent talent prize" was presented as a human resource to be pursued by current curriculum. The core competencies that future talent should have are self-management capacity, knowledge information processing capacity, creative thinking capacity, aesthetic capacity, communicative competence, and community competence. The researcher believes that among the six core competencies, the ability to have more attention today is aesthetic capacity and that mathematics education should pursue it. The mathematical teaching methods based on Rudolf Steiner's anthroposophy education theory is an education that actively raises the aesthetic sensitivity of students. Therefore, this study investigates the features of educational methods based on the Steiner's anthroposophy and examines mathematics education methods based on them.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.591-594
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• 2004

Recently, a tendency for development of seismic approach of foreign countries is capacity design development. Capacity design is rational seismic design concept of capacity protection considering not only earthquake magnitude, but also behavior of structure. For that reason, the most bridge seismic design specifications contain capacity protection provisions explicitly or implicitly. The capacity protection is normally related with slenderness effect of the columns, force transfer in connections between columns and adjacent elements, and shear design of columns. It intends to prevent brittle failure of the structural components of bridges, so that the whole bridge system may show ductile behavior and failure during earthquake events. The objectives of this paper are to deduce needed provisions for the moderate seismicity regions such as Korea after studying current seismic design codes and to establish rational criteria provisions of seismic design for future revision of seismic design specifications.

• KDI Journal of Economic Policy
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• v.41 no.2
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• pp.41-58
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• 2019

Health capacity to work for the elderly is an essential piece of information for designing social policies in an aging society. Here, we assess the health capacity to work of older men in South Korea and provide a cross-country comparison. Following the methodology proposed by Milligan and Wise (2012), which uses the cohort mortality rate as a proxy for overall health status, we quantify the additional employment capacity of current older men in reference to the mortality-employment relationship of a generation ago. Despite the high employment rate of older men in South Korea, we find substantial additional employment capacity among older men (those aged 55 or more) as of 2016 comparable in size to those found in other advanced countries. We also find evidence that older men are not merely capable of working but are also willing to work, and many of them are increasingly combining pension income and work. These findings suggest that labor supply disincentives for older men embedded in public pension systems in South Korea need to be thoroughly reexamined and adjusted accordingly lest they should inhibit the labor supply of older workers.