• Journal of the Korean Society for Heat Treatment
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• v.16 no.4
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• pp.197-204
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• 2003

Honeycomb structure has been fabricated by brazing method using 0.1 wt%C and 1.0wt%C carbon steel core and STS304 stainless steel face sheet. Core shear strength ratio in W and L directions was 1:1.03 in 7 mm cell size, whereas 1:1.45 in 4 mm cell size. Flexural strength on face sheet was 166.4 MPa (0.1 wt%C, W direction), 171.1 MPa (0.1 wt%C, L direction), and 120.2 MPa (1.0 wt%C, W direction) in 7 mm cell size. And in 4mm cell size specimen, it was 169.2 MPa (0.1 wt%C, W direction), 224.2 MPa (0.1 wt%C, L direction). This means that flexural strength of 0.1 wt%C core material was higher than that of 1.0wt%C core material, which was contrary to expectation. SEM and EDS analysis represented that grain boundary diffusion had occurred in0.1 wt%C core, but no grain boundary diffusion in 1.0 wt%C core. And corrugated surface of 0.1 wt%C core was flat, whereas that of 1.0 wt%C core was not flat. As a result, contact area between two 1.0 wt%C cores was much less than that of 0.1 wt% cores, It is thought to be main reason for lower flexural strength of 1.0 wt%C core.

• Polymer(Korea)
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• v.32 no.5
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• pp.470-477
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• 2008

Core shell binder of organic/organic pair that has two different properties within a particle were prepared by a step emulsion polymerization of methacrylate (MMA), styrene (St), ethyl acrylate (EA), butyl acrylate (BA), and 2-HEMA by using an water soluble initiator(APS) in the presence of an anionic surfactant (SDBS). Unwoven tensile strength of the core shell binder after processing and measuring the PSt/PMMA/2-HEM core shell with the binder is a value represents the highest was $10.75\;kg_f$/2.5cm, elongation measurements PEA/PBA core shell binder showed the highest value was 120.00%. In conclusion, using the core shell binders were able to control the mechanical properties such as tensile strength and elongation.

• Fibers and Polymers
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• v.5 no.1
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• pp.25-30
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• 2004

The present paper reports the impact of thermal treatment on the characteristics of core-sheath type hybrid technical yarns. The core-sheath type hybrid yams are prepared using DREF-III technology. Polyester and glass multifilaments are used as core components whereas the cotton and polyester staple fibers are the sheath components wrapped around the core filament with different proportions to form a hybrid structure. The thermal treatment is carried out both in dry and in wet state under relaxed condition and the thermal shrinkage, sheath-slipping resistance and tensile and bending properties of hybrid yarns have been studied. Thermal treatment markedly increases the thermal shrinkage and sheath-slipping resistance of hybrid yarns with polyester multifilament in core, but insignificant effect for yarns with glass multifilament in core. Breaking elongation of hybrid yams with polyester multifilament in core increases with treatment temperature. The hybrid yarns with glass multifilament in core are least affected by thermal treatment.

• IEIE Transactions on Smart Processing and Computing
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• v.4 no.2
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• pp.83-88
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• 2015

Core-A is 32-bit synthesizable processor core with a unique instruction set architecture (ISA). In this paper, the Core-A ISA is introduced with discussion of useful features and the development environment, including the software tool chain and hardware on-chip debugger. Core-A is described using Verilog-HDL and can be customized for a given application and synthesized for an application-specific integrated circuit or field-programmable gate array target. Also, the GNU Compiler Collection has been ported to support Core-A, and various predesigned platforms are well equipped with the established design flow to speed up the hardware/software co-design for a Core-A-based system.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.5
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• pp.385-393
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• 2021

This study proposes a multi-core-based controller design for an ESC(Electronic Stability Control) system in an automotive multi-core processor. Considering the architectures of an automotive multi-core processor and an ESC system, the overall execution time has been optimized for multi-core platforms. The function module assignment, synchronization between cores, and memory assignment for core-dependent variables in automotive multi-core systems are evaluated. The ESC controller comprising five function modules is used herein. Based on the proposed design, the single-core controller is extended to multi-core controllers. Using multi-core optimization methods, such as function module assignment, semaphore, interrupt awakening, and variable assignment over cores, the ESC system is redesigned to a multi-core controller. Experimental results reveal that the execution time for the multi-core processor is reduced by 59.7% compared with that for the single-core processor.

• IEIE Transactions on Smart Processing and Computing
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• v.5 no.1
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• pp.43-48
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• 2016

We propose plain fingerprint classification based on a core stochastic algorithm that effectively uses a core stochastic model, acquiring more fingerprint minutiae and direction, in order to increase matching performance. The proposed core stochastic algorithm uses core presence/absence and contains a ridge direction and distribution map. Simulations show that the fingerprint classification accuracy is improved by more than 14%, on average, compared to other algorithms.

• Progress in Superconductivity and Cryogenics
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• v.18 no.4
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• pp.35-39
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• 2016

In recent years, high-temperature superconductor (HTS) Quadruple Triplets are being developed for heavy ion accelerators, because the HTS magnets are suitable to withstand radiation and high heat loads in the hot cell of accelerators. Generally, an iron yoke, which costs a mass of material, was employed to enhance the magnetic field when a quadrupole magnet was designed. The type of the magnet is called iron-dominated magnet, because the total magnetic field was mainly induced by the iron. However, in the HTS superconductor iron-dominated magnets, the coil-induced field also can have a certain proportion. Therefore, the air-core HTS quadrupole magnets can be considered instead of the iron-core HTS quadrupole magnet to be employed to save the iron material. This study presents the design of an air-core HTS quadruple triplet which consists three by air-core HTS quadruple magnet and compare the design result with that of an iron-core HTS quadruple triplet. First, the characteristics of an air-core HTS quadrupole magnet were analyzed to select the magnet system for the magnetic field uniformity impairment. Then, the field uniformity was improved(< 0.1%) exactly using evolution strategy (ES) method for each iron-core HTS quadrupole magnet and the air-core HTS quadruple triplet was established. Finally, the designed air-core triplet was compared with the iron-core HTS quadruple triplet, and the results of beam trajectories were presented with both the HTS quadruple triplet systems to show that the air-core triplet can be employed instead of the iron-core HTS triplet. The design of the air-core quadruple triplet was suggested for a heavy ion accelerator.

• Structural Engineering and Mechanics
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• v.66 no.6
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• pp.783-792
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• 2018

This paper presents a detailed theoretical study of the sleeved compression members based on a mechanical model. In the mechanical model, the core protrusion above sleeve and the contact force between the core and sleeve are specially taken into account. Via the theoretical analyses, load-displacement relationships of the sleeved compression members are obtained and verified by the experimental results. On the basis of the core moment distribution changing with the increase of the applied axial load, failure mechanism of the sleeved compression members is assumed and proved to be consistent with the experimental results in terms of the failure modes and the ultimate bearing capacities. A parametric study is conducted to quantify how essential factors including the core protrusion length above sleeve, stiffness ratio of the core to sleeve, core slenderness ratio and gap between the core and sleeve affect the mechanical behaviors of the sleeved compression members, and it is concluded that the constrained effect of the sleeve is overestimated neglecting the core protrusion; the improvement of ultimate bearing capacity for the sleeved compression member is considered to be decreasing with the decrease of the core slenderness ratio and for the sleeved compression member with core of small slenderness ratio, small gap and small stiffness ratio are preferred to obtain larger ultimate bearing capacity and stiffness.

• Journal of KSNVE
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• v.9 no.4
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• pp.747-753
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• 1999

This paper presents results of vibration analysis of a generator-stator core for 500 MW fossil power plant. A finite element analysis using a commercial S/W is performed to estimate alternating electromagnetic forces, mainly of 120 Hz in 60 Hz machines, acting on the core, and then to calculate forced response of the core. Results are compared with design requirements.

• Journal of the Korean housing association
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• v.9 no.1
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• pp.99-107
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• 1998

This study intends to analyze residential satisfaction and preference of residents of urban core area. The main findings of this study are follows: First, the residents show high satisfaction levels for accessibility and availability of various facilities. However, they express relatively low levels of satisfaction for safety and amenities. Second, the satisfaction levels of female, housewives, and higher income earners are higher than the rest of residents. Third, more than half of core residents still want to live in the core area. This result implies the possibilities of residential development in the core area.