• Membrane Journal
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• v.1 no.1
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• pp.100-100
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• 1991

A novel system to thicken the concentrated colloidal solution from membrane water treat-ment processes was developed. A hollow-fiber microfilter(hydrophilic polyethylene nominal pore size 0.1 μm total surface area 0.42 m2) was installed in an acrylic housing that has an aeration port 5 cm below the membrane and a clarifier in the bottom. The concentrate was uniformly supplied from the top of the housing. Bacuum filtration caused downward flow of concentrate and as a result thickening interface. The addition of poly-aluminum chloride (PAC) resulted in rapid increase of trans-membrane pressure (TMP) and in no improvement of the filtered water turbidity and thickening process. Two types of con-centrate and concentrate turbidity had little effect on the increase of TMP and concentrate thickening. It was observed that for the same height of membrane housing membrane surface area to housing volume (A/V) ratio had significant effect on the increase of TMP. When the housing volume was increased ten times the increasing rate of TMP was three times faster as compared to the original housing. A hydraulic model successfully simulated the formation and sedimentation of thickening interface.

• Journal of Periodontal and Implant Science
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• v.25 no.2
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• pp.418-437
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• 1995

The effect of the hydroxyapatite coatings on Titanium implants has been the subject of recent investigations. So far, the use of HA coating remains substantially controversial.This study was aimed to evaluate histologically the bone healing patterns around titanium plasm sprayed(TPS) amd HA-coated implant after implantation into the femur neck of ten adult dogs. After implantation, animals were sacrificed at the intervals of 2,4,6,8 and 12 weeks.The fluorescent dyes were injected on the postoperative 4th and 12th week into the animals supposed to be killed at the 12th week. The morphology and direction of new bone formation was similar in both TPS and HA-coated implants.There was a tendency toward more bone formation in the cortical bone area than in the cancellous bone area. Histologically,in the interface of the HA-coated implants, bone response and bone maturation was faster, compared to the TPS implants in the 2nd and 4th week. By fluorescent microscopy, new bone formation was active in the 4th week around both implants and was directed from the periosteum overlying cortical bone to the cancellous bone. These results suggest that the bone formation and maturation is faster during the early healing stage in the interface of the HA-coated implant and where the cortical bone quality is poor, HA coated implant is superior to the TPS implant in the early phase of new bone formation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.11
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• pp.996-1000
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• 2005

Experimental results are presented for the degradation of 3 nm-thick gate oxide $(SiO_2)$ under both Negative-bias Temperature Instability (NBTI) and Hot-carrier-induced (HCI) stresses using P and NMOSFETS, The devices are annealed with hydrogen or deuterium gas at high-pressure $(1\~5\;atm.)$ to introduce higher concentration in the gate oxide. Both interface trap and oxide bulk trap are found to dominate the reliability of gate oxide during electrical stress. The degradation mechanism depends on the condition of electrical stress that could change the location of damage area in the gate oxide. It was found the trap generation in the gate oxide film is mainly related to the breakage of Si-H bonds in the interface or the bulk area. We suggest that deuterium bonds in $SiO_2$ film are effective in suppressing the generation of traps related to the energetic hot carriers.

• Journal of Korean Society for Geospatial Information Science
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• v.5 no.1 s.9
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• pp.41-55
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• 1997

An improved model of 'use' or 'region' districting(or regional zoning) scheme has been proposed. GIS based prototype model of managing the semi-agricultural region is implemented in a PC based platform focusing the Yongin, Kyonggi-Do area. Throughout the process of users' requirement analysis, database design, and user interface design, it has been shown that the integrated system may shed light on the prospective usage by the city or county government officials regardless of the short functionalities and user interface. This study aims first at identifying the needs in the area of districting at local level and at suggesting a basic framework of database design and system implementation in regard to region districting. The ARC/INFO, ArcView/Avenue based PC-based decision supports system presented herein is hoped to be supplemented with the inclusion of time factor in its database to cover and reflect the temporal variations associated with the plans.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.458-461
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• 2011

IT related services are available in the shipborne and maritime area. As their service requirements are requested diversely, the safe and reliable embedded system based device needs increase. There are two categories in embedded system : communication/control system and various user interface needed service system. In this paper, we propose the classification of embedded system in the shipborne and maritime area and provide two reference embedded system platforms and their components. One is low-level embedded reference platform of communication/control system and the other is high-level embedded reference platform of user interface oriented system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.177-181
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• 2004

It is as research about embodiment of MAC algorithm that is point of wireless LAN technology that is radio skill that is receiving present head of a family footlights, and embodied MAC that is algorithm that control modem Rf and host interface to level that existent common use radio AP and send-receive of high speed are available that embody function that is presented to IEEE 802.11 specs using H/W and S/W. When embody actually, tested module that embody actually using module modem and RF part because test is impossible after have common use product. Also, module that embody actually designed, and is expected to be utilized in radio LAN system construction of high speed late considering CRC and FCS ewer on channel.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.4
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• pp.252-260
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• 2005

In this research, case studies considering tunnel interface were conducted for zoning the ground into spatial area having similar geotechnical characteristics and estimating geotechnical properties for each area. The site for analysis consists of banded biotite gneiss, biotite schist and granite gneiss with spatial non-homogeneity, and for that reason weathering and fault zone were distributed with large scale. It's important thing to consider spatial ground zone and their geotechnical properties properly into stability analysis at design and construction stage. Also, in this studies, these analysis works are very useful for further decision making process by stability analysis.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.9
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• pp.300-306
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• 2012

In this paper, we propose a vision based hand motion recognition method for an untouchable user interface of smart devices. First, an original color image is converted into a gray scaled image and its spacial resolution is reduced, taking the small memory and low computational power of smart devices into consideration. For robust recognition of hand motions through separation of horizontal and vertical motions, the horizontal principal area (HPA) and the vertical principal area (VPA) are defined respectively. From the difference images of the consecutively obtained images, the center of gravity (CoG) of the significantly changed pixels caused by hand motions is obtained, and the direction of hand motion is detected by defining the least mean squared line for the CoG in time. For verifying the feasibility of the proposed method, the experiments are carried out with a vision system.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.4
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• pp.444-456
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• 2007

Statement of problem: Implant inclination and cantilever loading increse loads distributed to implants, potentially causing biomechanical complications. Controversy exists regarding the effect of the intentionally distal-inclined implant for the reduction of the cantilever length. Purpose: This study investigated the stress distribution at the bone/implant interface and prostheses with 3D finite element stress analysis by using four different cantilever lengths and implant inclinations in a mandibular implant-supported bar overdenture. Material and methods: Four 3-D finite element models were created in which 4 implants were placed in the interforaminal area and had four different cantilver lengths(10, 6.9, 4 and 1.5mm) and distal implant inclinations$(0^{\circ},\;15^{\circ},\;30^{\circ}\;and\;45^{\circ})$ respectively. Vortical forces of 120N and oblique forces of 45N were applied to the molar area. Stress distribution in the bone around the implant was analysed under different distal implant inclinations. Results: Analysis of the von Mises stresses for the bone/implant interfaces and prostheses revealed that the maximum stresses occurred at the most distal bone/implant interface and the joint of bar and abutment, located on the loaded side and significantly incresed with the implant inclinations, especially over $45^{\circ}$. Conclusion: Within the limitations of this study, it was suggested that too much distal inclination over 45 degrees can put the implant at risk of overload and within the dimension of the constant sum of a anterior-posterior spread and cantilever length, a distal implant inclination compared to cantilever length had the much larger effect on the stress distribution at the bone/implant interface.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.37 no.3
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• pp.86-92
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• 2000

In this paper, we develop protocol analyzer that can analyze and monitor LAN(Local Area Network)-based TCP/IP protocol using the OOP(object-oriented programming) in Windows98/NT environment. TCP/IP(Transmission Control Protocol/Internet Protocol) protocol analyzer is consist of interface hardware, protocol analysis software and GUI(Graphic User Interface). It is designed for the real-time analysis using the real-time object. In results of Performance test, TCP/IP Protocol analyzer is showed that it can analyze and monitor without frame error in LAN-based. Also, developed protocol analyser operates better than conventional protocol analyzer in performance. It can be used in maintenance fields of communication and network.