• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.334-337
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• 1996

Si anisotropic etching is a key technology for micromachining. The main advantages of tetramethyl ammonium hydroxide (TMAH)-based solution are their full compatibility with IC process. In this work the anisotropic etching of single crystal Si in a TMAH (($CH_3$)$_4$NOH) based solution was studied. The influence of the addition of IPA to TMAH solution on their etching characteristics was also presented. The crystal planes bounding the etch front and their etch rates were determined as a function of temperature, crystal orientation, and etchant concentration. The etch rates of (100) oriented Si crystal planes decreased linearly with increasing the IPA concentration, The etched (100) planes were covered by Pyramidal-shaped hillocks below 15 wt.%, but very smooth surfaces were obtained above 20 wt.%. The addition of IPA to TMAH solution leads to smoother surfaces of sidewalls etched planes.

• Korean Journal of Materials Research
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• v.20 no.2
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• pp.90-96
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• 2010

The recirculating electrochemical flow reactor developed at UCLA has been employed to fabricate nanostructured GMR multilayers. For comparison, Ni/Cu multilayers have been electrodeposited from a single bath, from dual baths and from the recirculating electrochemical flow reactor. For a magnetic field of 1.5 kOe, higher GMR (Max. -5%) Ni/Cu multilayers with low electrical resistivity (< $10\;{\mu}{\Omega}{\cdot}cm$) were achieved by the electrochemical flow reactor system than by the dual bath (Max. GMR = -4.2% and < $20\;{\mu}{\Omega}{\cdot}cm$) or the single bath (Max. GMR = -2.1% and < $90\;{\mu}{\Omega}{\cdot}cm$) techniques. Higher GMR effects have been obtained by producing smoother, contiguous layers at lower current densities and by the elimination of oxide film formation by conducting deposition under an inert gas environment. Our preliminary GMR measurements of Ni/Cu multilayers from the electrochemical flow reactor obtained at low magnetic field of 0.15 T, which may approach or exceed the highest reported results (-7% GMR) at magnetic fields > 5 kOe.

• Journal of the Korea Safety Management & Science
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• v.6 no.3
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• pp.175-186
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• 2004

The compatibility of the enterprises of Korea was the 'low cost and mass production＆apos;. That in because, the entire business transactions including production, accounting, personnel management, and logistics need to be integrated with a global perspective. Logistics information system is to support the management of such logistics activities and involves in a wide range of the business operations. In other words, the logistics information system is 0 accurately and rapidly deliver and process the information available for the logistics in order to promote more smoother and efficient logistics by using such information. I'll give a brief introduction to the SRM(Supplier Relationship Management) system and go into the problem that should be considered and which phase to emphasize when building this system.

• Corrosion Science and Technology
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• v.5 no.1
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• pp.15-22
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• 2006

The introduction of two-grid inside a conventional process system produces a reactive coating deposition and increases metal ion ratio in the plasma, resulting in denser and smoother films. The corrosion behaviors of TiN coatings were investigated by electrochemical methods, such as potentiodynamic polarization test and electrochemical impedance spectroscopy (EIS) in deaerated 3.5% NaCl solution. Electrochemical tests were used to evaluate the effect of microstructure on the corrosion behavior of TiN coatings exposed to a corrosive environment. The crystal structure of the coatings was examined by X-ray diffractometry (XRD) and the microstructure of the coatings was investigated by scanning electron microscopy (SEM) and transmission electron spectroscopy (TEM). In the potentiodynamic polarization test and EIS measurement, the corrosion current density of TiN deposited by two grid-attached magnetron sputtering was lower than TiN deposited by conventional magnetron type and also presented higher Rct values during 240 h immersion time. It is attributed to the formation of a dense microstructure, which promotes the compactness of coatings and yields lower porosity.

• Journal of the Optical Society of Korea
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• v.15 no.2
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• pp.118-123
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• 2011

A novel triangular-shaped plasmonic metal-insulator-metal (MIM) Bragg grating waveguide is introduced, whose band-gap is narrower than that of the conventional step type and wider than that of the sawtoothshaped one. Moreover apodized triangular-shaped MIM Bragg grating structures are proposed in order to reduce the side lobes of the transmission spectrum, because the Bragg reflector with a sawtooth profile has a smoother transmission spectrum than that of a triangular-shaped one. The performance of the proposed structures is simulated by using the finite difference time domain method.

• Korean Journal of Computational Design and Engineering
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• v.12 no.5
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• pp.354-365
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• 2007

We present novel methods to generate a sequence of shapes that represents the pattern of morphological development or transformation of Bezier curves. The presented methods utilize the intrinsic geometric structures of a Bezier curve that are derived from rib and fan decomposition (RFD). Morphological development based on RFD shows a characteristic pattern of structural growth of a Bezier curve, which is the direct consequence of development path defined by fans. Morphological transformation based RFD utilizes development patterns of source and target curves to mimic the theory of evolutionary developmental biology: although the source and target curves are quite different in shapes, we can easily find similarities in their younger shapes, which makes it easier to set up feature correspondences for blending them. We also show that further controls on base transformation for intensity of feature blending, and extrapolation can compensate the immaturity of blended curves. We demonstrate the experimental results where transformation patterns are smoother and have unique geometric style that cannot be generated using conventional methods based on multi-linear blending.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.9
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• pp.2237-2248
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• 1995

In incompressible flow which has multi-length scale, it has a very important effect which dependent variables are used for adaptive grid generation. Among many length scales in incompressible flow, the dependent variables used for the adaptive grid generation should be able to represent the feature of the concerned system. In this paper, by using vorticity and stream function, in addition to velocity components, the smoother and more stable grid generation is possible and these four flow properties represent each scale. The adaptive grid generation for a lid-driven cavity flow with $N_{re}$ =3200 using four flow properties such as velocity components, vorticity, stream function is performed, and the usefulness of using vorticity and stream function as the indicator for adaptive grid generation is shown.

• Korean Journal of Human Ecology
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• v.1 no.2
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• pp.119-128
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• 1998

Nonwoven fabrics for diaper coverstock were treated with chitosan solution by pad-dry method. Two chitosans of different molecular weigh(Mw) with similar degree of deacetylation(DDA) were used: Mw 1,800(chitosan oligomer, DDA 84%). Effect of chitosan treatment on the mechanical properties was investigated using KES-FB system. Primary hand values were calculated from mechanical properties using the same equation as the men's suiting equation with minor modification, and total hand values were calculated using new KN-5LNW equation for nonwoven fabrics developed by Kawabata et al. Increase in chitosan treatment concentration increased B, 2HB, WT, LT and RC, and decreased WC continuously. Chitosan treatment affected other mechanical properties regardless of molecular weight. Considering primary hand values obtained from mechanical properties, it was found that chitosan of Mw 180,000 and chitosan oligomer provided softer, smoother, and more bulky at below 0.05% and above 0.5% treatment concentration respectively. Samples treated with 1.0% chitosan oligomer solution, and 0.01％ chitosan solution of Mw 180,000 showed the best total hand values. (Korean J Human Ecology 1(2):119∼128, 1998)

• Proceedings of the Safety Management and Science Conference
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• 2005.05a
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• pp.417-428
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• 2005

Recently, Vendor Managed Inventory(VMI) is commonly recognized as one of the supply chain application that delivers clear value to the sectors of electic& electronic Components. VMI is a process in which a supplier generates orders for its distributor based on demand information sent by the distributor. VMI is providing the benefits of smoother demand, lower inventories and reduced costs. This case study focused on Improvement of Inventory Efficiency by VMI. The results indicated that VMI allowed the company to serve its customers more surely and efficiently.

• English Language & Literature Teaching
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• v.16 no.3
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• pp.119-139
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• 2010

The purpose of this paper was to examine various aspects of meaning negotiation process in online chatting. Korean college students were asked to engage in chatting on the Internet over the course of a semester-long period, and chatting transcripts were analyzed in terms of sources of communication breakdown, signals to indicate communication breakdown, strategies to overcome communication breakdown, and ways of closing meaning negotiation. According to the findings of the study, lack of background knowledge and incoherent string of sentences in text were two major barriers creating communication problems. Subjects were able to use signals to indicate their communication difficulties, and overcome them by using different strategies. In doing so, however, they were found to suffer a narrow range of signals and strategies, which showed their limited communicative ability in the management of interaction, and indicated a clear, strong need for an extension of discourse and strategic competences of Korean students for more effective and smoother transition of message in everyday interaction.