• Proceedings of the KSME Conference
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• 2007.05a
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• pp.238-243
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• 2007

This paper is designed to estimate the adhesion strength of coating layer on galvannealed steel sheet using lap shear test. The single lap shear test is the most commonly used standard test for determining the strength of medium-strength and high strength bonds. The bond strength of bonded single lap joints on subjecting the substrates to loads is determined by lap shear forces in the direction of the bonded joint. In this study, specimen for adhesion strength test was made to attach coated sheet to cold rolled sheet and were heated in temperature of 180 for 20minutes. After test, detached parts of coatings on coated sheet were observed using SEM and EDX to identify substrate and complete detachment. The tested results showed that adhesive strength of coating is unrelated to anisotropy of sheet and is difficult to be extracted using conventional theory because of fine cracks of coating layers which were created during annealing process.

• Journal of Pharmaceutical Investigation
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• v.35 no.6
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• pp.445-451
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• 2005

As a selective ${\alpha}_{1A}-adrenoreceptor$ antagonist, tamsulosin has been used clinically for urinary obstructed patients with benign prostatic hyperplasia. The single and multi-layered pellets containing tamsulosin hydrochloride were prepared in an effort to control the drug release, avoiding dose-dependent side effects of tamsulosin hydrochloride upon oral administration. The drug release from multi-layered pellets was substantially controlled, compared with single layered pellets. The drug release from coated pellets with single or multi layer was affected by the nature of coating agent, the percentage of coating level and the presence of hydrophilic material in coating layer. In conclusion, the controlled release oral delivery system using multi-layered pellet is very useful for tamsulosin hydrochloride, resulting in improvement of patient compliance and therapeutic drug levels for a longer period of time.

• Journal of the Korea Computer Industry Society
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• v.5 no.1
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• pp.49-56
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• 2004

With the growing usage of the networks, the users in the Internet uses some kinds of web server. They confused that each web server uses the different user ID and passwords. To solve these problems, SSO (Single Sign-On) solution is introduced. We presents the modeling methods which are efficiently constructed the network management models. We constructed the intrusion detection systems and firewalls using the SSO. This architecture is efficient to manage the network usage and control. SSO solution designed on the small scale Intranet. CA server in the 550 that depends on PKI (Public Key Infrastructure) is used to issue the certificates. SHTTP based on SSL (Secure Socket Layer) is used to protect the data between certificate server and the intranet users.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.32-35
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• 2002

The work focuses on the development of a Cu lead-frame with a single-sided adhesive tape for cost reduction and reliability improvement of LOC (lead on chip) package products, which are widely used for the plastic-encapsulation of memory chips. Most of memory chips are assembled by the LOC packaging process where the top surface of the chip is directly attached to the area of the lead-frame with a double-sided adhesive tape. However, since the lower adhesive layer of the double-sided adhesive tape reveals the disparity in the coefficient of thermal expansion from the silicon chip by more than 20 times, it often causes thermal displacement-induced damage of the IC pattern on the active chip surface during the reliability test. So, in order to solve these problems, in the resent work, the double-sided adhesive tape is replaced by a single-sided adhesive tape. The single-sided adhesive tape does net include the lower adhesive layer but instead, uses adhesive materials, which are filled in clear holes of the base film, just for the attachment of the lead-frame to the top surface of the memory chip. Since thermal expansion of the adhesive materials can be accommodated by the base film, memory product packaged using the lead-flame with the single-sided adhesive tape is shown to have much improved reliability. Author allied this invention to the Korea Patent Office for a patent (4-2000-00097-9).

• Journal of the Korean Magnetics Society
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• v.9 no.5
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• pp.227-233
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• 1999

The magnetic field in single-layer solenoid with multi-current is calculated using Elliptical function, Legendre polynomials and Biot-Savart law. The optimization conditions to a highly uniform magnetic field in the center of solenoid has been studied. The variation of magnetic field depending on radius difference was examined. The uniformity of magnetic field is compared with that obtained each multi-current method. The five-current method increases the working space within 0.02 ppm uniformity by eighty times that using single current method. And this method improves the magnetic field uniformity which is equivalent to the effect of 160 m long solenoid by using single current.

• Applied Microscopy
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• v.24 no.1
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• pp.102-113
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• 1994

A thin section of the methanogenic archaebacterium, Methanoplanus limicola, shows that the surface glycoprotein array (S-layer) is separated from plasma membrane by a distinct inter-space, approximately 4.0-6.0nm wide. We report our structural study of the S-layer by electron crystallographic techniques. Image analysis and thin sections of the S-layer treated with and without triton disclosed that retention of the single layer crystal requires the presence of detergent to avoid hydrophobic bonding.

• Journal of information and communication convergence engineering
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• v.18 no.2
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• pp.82-87
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• 2020

This paper discusses how to design a game server that is scalable, adaptable, and re-buildable with components. Furthermore, it explains how various implementation issues were resolved. To support adaptability, the server comprises three layers: network, user, and database. To ensure independence between the layers, each layer was designed to communicate with each other only via message queues. In this architecture, each layer can have an arbitrary number of threads; thus, scalability is guaranteed for each layer. The network layer uses input/output completion ports(IOCP), which shows the best performance on the Windows platform, it can handle up to 5,000 simultaneous connections on a typical entry-level computer, despite being built with a single-threaded user layer. To completely separate the database from the game server, the SQL code was not directly embedded in the database layer.

• International Journal of Fluid Machinery and Systems
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• v.1 no.1
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• pp.24-32
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• 2008

Bleeding away a part of the boundary layer next to the wall is an effective method for controlling boundary-layer distortions from incident shock waves or curvature in geometry. When the boundary-layer flow is supersonic, the physics of bleeding with and without an incident shock wave is more complicated than just the removal of lower momentum fluid next to the wall. This paper reviews CFD studies of shock-wave/boundary-layer interactions on a flat plate with bleed into a plenum through a single hole, three holes in tandem, and four rows of staggered holes in which the simulation resolves not just the flow above the plate, but also the flow through each bleed hole and the plenum. The focus is on understanding the nature of the bleed process.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.6
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• pp.1068-1073
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• 1987

Traditional circuit partitioning algorithm using the cluster development method, which is suitable for such applications as single chip floor planning or multiple layer PCB system placement, where the clusters are formed so that inter-cluster nets are localized within the I/O connector pins, may not be appropriate for the functiona block placement in truly 3-D electronic modules. 3-D hybrid IC is one such example where the inter-layer routing as well as the intra-layer routing can be maximally incorporated to reduce the overall circuit size, cooling requirements and to improve the speed performance. In this paper, we propose a new algorithm called MBE(Minimum Box Embedding) for the layer assignment of each functional block in 3-D hybrid IC design. The sequence of MBE is as follows` i) force-directed relaxation in 3-D space, ii) exhaustive search for the optimal orientation of the slicing plane and iii) layer assignment. The algorithm is first explaines for a 2-D reduced problem, and then extended for 3-D applications. An example result for a circuit consisting of 80 blocks has been shown.

• Journal of Environmental Science International
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• v.4 no.5
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• pp.481-488
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• 1995

This study was carried out to evaluate the variations of headloss rate and of specific deposit to depths with effective size of media and configuration of filter layer during algae blooming period. 0.51mm size media was disqualified because most of headloss occurred rapidly below 5cm from surface layer however 0.91mm size media acted deep filtration more than 20cm from top, as result 0.91mm sixte media filter had 2~3 times longer filtration time than 0.51mm sixte media filter, but 0.91mm size media have break-through potentiality. multi-layer filter with 1.02mm anthracite and 0.51mm sand had large deposit volume in upper layer that could longer filtration time, moreover smaller media in lower layer that could protect break-through.