• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.251-257
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• 1999

Smart structure that contains sensors, which are either embedded in a composite material or attached to a structure, is currently receiving considerable attention. Fiber Bragg grating sensor, one of the optical fiber sensors, has been widely used to sense strain and temperature for smart structures since both parameters change the resonant frequency of the grating. In this paper, according to the various heating and cooling conditions the thermal behavior of unidirectional composite material was monitored by embedding the fiber Bragg grating sensors in the longitudinal and transverse directions of unidirectional composites. The thermal behavior of unidirectional composite material was monitored for various heating and cooling rates and applied pressure. It was found that the thermal behavior was unaffected by pressure variations and heating and cooling rates applied to the composites. The thermal strains were measured by considering the shift in Bragg wavelength that was generated by the thermal expansion of composite specimen. The longitudinal and transverse C.T.E.'s were also obtained from the corresponding temperature-thermal strain curves.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.292-295
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• 2003

Moire topography method is a well-known non-contacting 3-D measurement method. the automatic 3-D measurement by moire topography has been required since the method was frequently applied to the engineering and medical fields. 3-D measurement using digital projection moire topography is very attractive because of its high measuring speed and high sensitivity. In this study, digital two-wavelength phase shilling moire is applied to the entertainment fields. recently. as promoting the growth of the VR-Game, display devices which attract public attention such as HMD or Projector are being appeared in order to deliver effectively the absorption sense. this study realized the Auto-calibrating system for arbitrary display surface using digital moire method which satisfied the shape measurement of display surface and the request of FOV(Field of View) output. also when large screen wasn't prepared, this auto-calibrating system was applied to enjoy games or movies at home with a projector and walls

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.6
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• pp.556-561
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• 2013

Interest in spin-torque oscillators (STOs) has been increasing due to their potential use in communication devices. In particular the magnetic tunnel junction-based STO (MTJ-STO) with high perpendicular anisotropy is gaining attention since it can generate high output power. In this paper, a circuit-level model for an in-plane magnetized MTJ-STO with partial perpendicular anisotropy is proposed. The model includes the perpendicular torque and the shift field for more accurate modeling. The bias voltage dependence of perpendicular torque is represented as quadratic. The model is written in Verilog-A, and simulated using HSPICE simulator with a current-mirror circuit and a multi-stage wideband amplifier. The simulation results show the proposed model can accurately replicate the experimental data such that the power increases and the frequency decreases as the value of the perpendicular anisotropy gets close to the value of the demagnetizing field.

• Phonetics and Speech Sciences
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• v.9 no.3
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• pp.57-65
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• 2017

The current study explored how Korean-speaking children processed the multiple acoustic cues (VOT and f0) for the stop laryngeal contrast (/t'/, /t/, and /$t^h$/) and examined whether individual perceptual strategies could be related to a general cognitive ability performing executive functions (EF). 15 children (aged from 7 to 8) participated in the speech perception task identifying the three Korean laryngeal stops (3AFC) on listening to the auditory stimuli of C-/a/ with synthetically varying VOT and f0. They completed a series of EF tasks to measure working memory, inhibition, and cognitive shifting ability. The findings showed that children used the two cues in a highly correlated manner. While children utilized VOT consistently for the three laryngeal categories, their use of f0 was either reduced or enhanced depending on the phonetic categories. Importantly, the children's processing strategies of a f0 suppression for a tense-aspirated contrast were meaningfully associated with children's better cognitive abilities such as working memory, inhibition, and attentional shifting. As a preliminary experimental investigation, the current research demonstrated that listeners with inefficient processing strategies were poor at the EF skills, suggesting that cognitive skills might be responsible for developmental variations of processing sub-phonemic information for the linguistic contrast.

• Knowledge Management Research
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• v.21 no.2
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• pp.21-40
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• 2020

Korea Credit Guarantee Fund(KODIT) is a public financial institution under the provision of the Korea Credit Guarantee Fund Act. Facing the waves of change both locally and globally, KODIT will serve as 'social value creator' in making a paradigm shift from a large corporation(Conglomerate-dominated) economy to a social enterprise-oriented one based on social economy. This study focuses on the supporting service programs for social enterprises and job creation how it affects the performance of social value creation of KODIT. There is currently no detailed research of the social value in terms of the business and management academic agenda. Therefore, the present study describes the importance of social value creation on the policy financial institution. This study conducted in-depth case study for social value performance. As a public policy financial institution, KODIT exert diverse efforts to correct market failure and achieve inclusive growth. For example, KODIT extends credit guarantee services for the liabilities of promising corporations and stimulates financial and non-financial supporting programs for social enterprises. Although the role of social value and social economy has gained business field attention, few investigations have been conducted to explain how social value is achieved. The present study can thus act as the foundation for exploring the social value creation in the circumstances of public financial institution.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.4
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• pp.1-8
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• 2018

In drilling Inconel 601, which is used for compressor cases in aircraft engines, a lot of cutting oil must be supplied. This prevents tools from wear and fracture due to the heat buildup resulting from the high-temperature resistance and toughness of this alloy. However, the cutting oil supply has compromised the machining environment. This has caused attention to shift to an environmentally friendly cutting fluid supply system called the Minimum Quantity Lubrication(MQL) system. The aim of this study was to find a more efficient drill processing method using MQL and to verify its performance. To that end, the properties of Inconel that make it difficult -to -drill were studied by a comparison with the drilling of SM45C. Specific factors (i.e., cutting force and tool wear) were examined in relation to the conditions in the MQL-based drilling system. Based on these results, a sealed cover and step feed were proposed as measures to increase the effectiveness of the MQL system. The efficiency of the proposed method was established.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.204.2-204.2
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• 2014

Among various metal oxides, ZrO2 is of particular interests and has received widespread attention thanks to its ideal mechanical and chemical stability. As a cheap metal, Ag nanoparticles are also widely used as catalysts in ethylene epoxidation and methanol oxidation. However, the nature of Ag-ZrO2 interfaces is still unknown. In this work, the growth, interfacial interaction and thermal stability of Ag nanoparticles on ZrO2(111) film surfaces were studied by low-energy electron diffraction (LEED), synchrotron radiation photoemission spectroscopy (SRPES), and X-ray photoelectron spectroscopy (XPS). The ZrO2(111) films were epitaxially grown on Pt(111). Three-dimensional (3D) growth model of Ag on the ZrO2(111) surface at 300 K was observed with a density of ${\sim}2.0{\times}1012particles/cm2$. The binding energy of Ag 3d shifts to low BE from very low to high Ag coverages by 0.5 eV. The Auger parameters shows the primary contribution to the Ag core level BE shift is final state effect, indicating a very weak interaction between Ag clusters and ZrO2(111) film. Thermal stability experiments demonstrate that Ag particles underwent serious sintering before they desorb from the zirconia film surface. In addition, large Ag particles have stronger ability of inhibiting sintering.

• The Korean Journal of Community Living Science
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• v.25 no.1
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• pp.51-64
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• 2014

With a shift in the rural development process toward a bottom-up approach, the need to enhance the endogenous capacity of communities has become the core of rural development. In this regard, scholars have paid close attention to social capital to identify ways to facilitate endogenous rural development but focused mainly on relationships between social capital and local environment. That is, few studies have investigated the relationships between social capital and its various dimensions in the context of rural development initiatives. This study examines the effects of social capital on the problem-solving ability of community residents'rural development initiatives and assesses the types of social capital associated with such initiatives to propose optimal path for improving this ability. To distinguish between major dimensions of social capital, a questionnaire was developed by considering various stages of the rural development process. The survey considered a sample of 59 employees from public rural development institutions. According to the results, four paths were significant at the 5% level. Among these four paths, three set common goals. The effective channel was the path [common goals${\Rightarrow}$network${\Rightarrow}$cooperation${\Rightarrow}$problem-solving ability]. The key factor in improving problem-solving skills, the endogenous ability of community residents to facilitate rural development initiatives. The results suggest that governments should strengthen education and training programs to help residents set their common goals.

• Journal of Fashion Business
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• v.11 no.2
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• pp.129-144
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• 2007

These days, public attention is being directed to the design processes by which a final outcome can be produced to achieve its goal according to the logical plans, as it is hard to address recent problems in design by the existing intuitive way due to the paradigm shift of design. Thus, this study aims to suggest creative fashion design processes to create a product as a final outcome by intentional and systematic processes. This study showed that design is considered as comprehensive problem solving processes, and it proposes framework of processes by integrating processes of industrial design and fashion design. In addition, this study classified creativity development methods that can be implemented to fashion design into promotion of ideas, breaking out of stereotypes, and extension of search areas. These creativity development methods can be applied to fashion design processes in order to make plans and strategies systematically and help you to choose the best ways to solve problems by processes.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1463-1465
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• 1994

The electrical characteristics of $Al/Ta_2O_5/Si$ metal-oxide-semiconductor (MOS) capacitors were studied. $Ta_2O_5$ films on p-type silicon had been prepared by ionized cluster beam epitaxy technique (ICBE). This $Ta_2O_5$ films have low leakage current, high breakdown strength and low flat band shift. In this research, a single crystalline cpitaxial film of $Ta_2O_5$ has been grown on p-Si wafer using an ICBE technique. The native oxide layer ($SiO_2$) on the silicon substrate was removed below $500^{\circ}C$ by use of an accelerated arsenic ion beam, instead of a high temperature deposition. $Ta_2O_5$ films formed by ICBE technique can be received considerable attention for applications to coupling capacitors, gate dielectrics in MOS devices, and memory storage capacitor insulator because of their high dielectric constants above 20 and low temperature process.