• Progress in Superconductivity and Cryogenics
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• v.19 no.3
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• pp.1-7
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• 2017

It is required to reduce the cost of superconducting cable to realize a superconducting DC power network that covers a wide area in order to utilize renewable energy. In this paper a new concept of innovative cable is introduced that can enhance the current-carrying capacity even though the same superconducting tape is used. Such a cable can be realized by designing an optimal winding structure in such a way that the angle between the tape and magnetic field becomes small. This idea was confirmed by preliminary experiments for a single layer model cable made of Bi-2223 tapes and REBCO coated conductors. Experiments of three and four layer cables of practical sizes were also done and it was found that the current-carrying capacity increased as theoretically predicted. If the critical current properties of commercial superconducting tapes are further improved in a parallel magnetic field, the enhancement will become pronounced and this technology will surely contribute to realization of superconducting DC power network.

• Structural Engineering and Mechanics
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• v.39 no.2
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• pp.287-301
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• 2011

This paper is focused on the residual capacity of steel columns, as a damage criterion. Load-Impulse (P-I) diagrams are frequently used for analysis, design, or assessment of blast resistant structures. The residual load carrying capacity of a simply supported steel column was derived as a damage criterion based on a SDOF computational approach. Dimensionless P-I diagrams were generated numerically with this quantitative damage criterion. These numerical P-I diagrams were used to show that traditional constant ductility ratios adopted as damage criteria are not appropriate for either the design or damage assessment of blast resistant steel columns, and that the current approach could be a much more appropriate alternative.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.247-251
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• 2002

In this paper the maximum current carrying capability of ACAs flip chip joint is investigated based on two failure mechanisms: (1) degradation of the interface between gold stud bumps and aluminum pads; and (2) ACA swelling between chips and substrates under high current stress. For the determination of the maximum allowable current, bias stressing was applied to ACAs flip chip joint. The current level at which current carrying capability is saturated is defined as the maximum allowable current. The degradation mechanism under high current stress was studied by in-situ monitoring of gold stud bump-aluminum pad ACA contact resistance and also ACA junction temperature at various current level. The cumulative failure distributions were used to predict the lifetime of ACAs flip chip joint under high current stressing. These experimental results can be used to better understand and to improve the current carrying capability of ACA flip chip joint.

• Journal of the Korean Society of Safety
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• v.8 no.4
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• pp.120-126
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• 1993

This work was carried out to investigate the effects of solid mass flow rate, mean particle diameter and mesh number of screen packing material on minimum carrying velocity, which defined as the superficial gas velocity of the upper limit of chocking phenomenon. Vertical pneumatic conveying was studied on a 4.6cm 1. D. pipe, 180cm in length. Experiments were performed in both the empty and the screen-packed pipe. It was also examined the effect of superficial gas velocity, solid mass flow, mean particle diameter, and mesh number of packing material on pressure drop. Minimum carrying velocity in screen packed-pipe was lower than that in an empty pipe. besides minimum carrying velocity was decreased with increase in mesh number of screen packing material. The pressure drop In vortical packed-pipe was Increased with superficial gas velocity, mean particle diameter, and mesh number of screen packing material.

• MALSORI
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• no.35_36
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• pp.101-119
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• 1998

By analyses of lullabies, nursery rhymes, Christmas carols, and pop songs, the relevances of beat, syllable and note are set up as follows. (1) The relevance of beat to syllable a. A stressed syllable can occupy a strong beat. b. A monosyllabic word carrying a strong beat must have the syllabic structure of a strong syllable. (2) The note duration a. The duration of a note carrying a strong beat tends to be as long as or longer than that of a note carrying a weak beat. b. The note connected with the last position of phonological unit tends to be longer than that of other position without regard to the syllabic structure.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.391-394
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• 2008

Durability of product is an important technical parameter of a current interception device (CID) filter. This parameter is influenced by several factors, such as: environment condition, external force, shape of device, heat and so on. In this study, the effect of the geometry of the device on durability was carried out. The effect of shape on durability of device is presented by force-carrying capacity that a device can sustain a maximum external force. Studied parameters of the CID filter's geometry include clearance, thickness, and corner radius. Fracture criterion of Cockcroft and Latham was also used to predict the maximum force-carrying capacity of device.

• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.2
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• pp.141-146
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• 1999

Recently, many existing bridges has been evaluated for maintenance and protection of collapse. In this study, field measurement according to truck loads tests on the reinforce concrete T beam bridge was carried out. Comparing the results of load test and structural analysis using the moments of inertia of gross section, crack section and effective section, and the moments of inertia of section considering depth of crack, it is conclude that the evaluation of load carrying capacity using the stress modification factor from structural analysis using the moments of inertia of gross section is more rational than using the other moments of inertia of sections.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.605-613
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• 2006

The goal of this study was to propose building strategies of web-based national park monitoring system (WNPMS) using geographic information analysis system. To accomplish this study, at first, this study selected and made integrated management indicators considering physical, ecological, and socio-psychological carrying capacity in national park. Secondly, this study built up an integrated management this system with statistical analysis program for execution of various multivariate analysis and spatial analysis. Finally, WNPMS could identify the relationship among visitors, natural resources, and recreation facilities in national park, and forecast the future management status of each national park in Korea. There results of this study will contribute to prevent the damage of natural resources and facilities, improve visitor's satisfaction, prevent an excess of carrying capacity at national park, and established tailored management strategies of each national park.

• Structural Engineering and Mechanics
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• v.25 no.6
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• pp.675-690
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• 2007

In order to study the ductility and the lateral load carrying capacity of the masonry walls strengthened with CFRPs (Carbon Fiber Reinforced Polymer sheets), three pieces of masonry walls subjected to cyclic loads with low frequency and vertical load of constant amplitude have been tested. Two different strengthening methods have been used. The strengthening efficiency is affected by the strengthening method. A simplified calculation approach has been introduced based on the experimental test results, and the theoretical results agree reasonably well with the experimental results. It is found that the critical loads, the critical displacements, the ultimate loads, the ultimate displacements and the ductile coefficients of the masonry walls strengthened with CFRPs improve remarkably (6%~57%). Therefore, the masonry structures strengthened with CFRPs are of better ductility and of better lateral load carrying capacity than the masonry structures without any strengthening measurements.

• Journal of the Korean Mathematical Society
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• v.58 no.5
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• pp.1227-1237
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• 2021

This paper is concerned with a reaction-diffusion logistic model. In [17], Lou observed that a heterogeneous environment with diffusion makes the total biomass greater than the total carrying capacity. Regarding the ratio of biomass to carrying capacity, Ni [10] raised a conjecture that the ratio has a upper bound depending only on the spatial dimension. For the one-dimensional case, Bai, He, and Li [1] proved that the optimal upper bound is 3. Recently, Inoue and Kuto [13] showed that the supremum of the ratio is infinity when the domain is a multi-dimensional ball. In this paper, we generalized the result of [13] to an arbitrary smooth bounded domain in ℝⁿ, n ≥ 2. We use the sub-solution and super-solution method. The idea of the proof is essentially the same as the proof of [13] but we have improved the construction of sub-solutions. This is the complete answer to the conjecture of Ni.