• Journal of the Korean GEO-environmental Society
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• v.11 no.11
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• pp.37-45
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• 2010

In this study, the value of numerical analysis was compared to the measured value of horizontal displacement during construction. And also, the value was reviewed by comparing with numbers calculated by SUNEX program and EXCAV program. When comparing to suggested values of the maximum horizontal displacement in clayey layer, the displacement caused by the IPS system is larger than one by the Strut girder type system. When comparing the result of SUNEX program to that of EXCAV program, the SUNEX program interprets larger value. It could be concluded the result of SUNEX program is closer to the suggested value, 0.5%H, in clayey layer. The result also shows that the internal friction angle(${\Phi}$) is the key factor of developing horizontal displacement rather than type of supporting systems or materials. That means small horizontal displacement occurs in sandy layer having large value of the internal friction angle, whereas vice versa in clayey layer having small value of the internal friction angle. Therefore, the result of EXCAV program is larger in sandy layer and vice versa in clayey layer. When comparing the measured result during construction to the value of 0.5%H, the measured result is 1.4 times greater than the value of 0.5%H. In contrast, the result of SUNEX program is only 78.1% of the value of 0.5%H and the one of EXCAV program is just 18.1% of that. This result shows the calculated value by SUNEX or EXCAV program is smaller than the observed value by measuring during construction. In result, more careful attention is needed to determine the behavior of the ground. To better analyze the behavior of the ground, more precise finite element method is required.

• Journal of dental hygiene science
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• v.18 no.1
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• pp.42-49
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• 2018

The computer-aided design/computer-aided manufacturing (CAD/CAM) system was introduced to shorten the production time of all-ceramic restorations and the number of patient visits. Among these types of ceramic for dental CAD/CAM, they have been processed into inlay, onlay, and crown shapes using leucite-reinforced glass-ceramics to improve strength. The purpose of this study was to observe the mechanical properties and microstructure of leucite-reinforced glass-ceramics for dental CAD/CAM. Two types of leucite-reinforced glass-ceramic blocks (IPS Empress CAD, Rosetta BM) were prepared with diameter of 13 mm and thickness of 1 mm. Biaxial flexural testing was conducted using a piston-on-three-ball method at a crosshead speed of 0.5 mm/min. Weibull statistics were used for the analysis of biaxial flexural strength. Fracture toughness was obtained using an indentation fracture method. Specimens were observed by field emission scanning electron microscopy to examine the microstructure of the leucite crystalline phase after acid etching with 0.5% hydrofluoric acid aqueous solution for 1 minute. The results of strength testing showed that IPS Empress CAD had a mean value of $158.1{\pm}8.6MPa$ and Rosetta BM of $172.3{\pm}8.3MPa$. The fracture toughness results showed that IPS Empress CAD had a mean value of $1.28{\pm}0.19MPa{\cdot}m^{1/2}$ and Rosetta BM of $1.38{\pm}0.12MPa{\cdot}m^{1/2}$. The Rosetta BM sample exhibited higher strength and fracture toughness. Moreover, the crystalline phase size and ratio were increased in the Rosetta BM sample. The above results are expected to elucidate the basic mechanical properties and crystal structure characteristics of IPS Empress CAD and Rosetta BM. Additionally, they will help develop leucite-reinforced glass-ceramic materials for CAD/CAM.

• The Journal of Advanced Prosthodontics
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• v.8 no.6
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• pp.479-488
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• 2016

PURPOSE. The aim of this study was to test the modulus of elasticity (E) across the interfaces of yttria stabilized zirconia (YTZP) / veneer multilayers using nanoindentation. MATERIALS AND METHODS. YTZP core material (KaVo-Everest, Germany) specimens were either coated with a liner (IPS e.max ZirLiner, Ivoclar-Vivadent) (Type-1) or left as-sintered (Type-2) and subsequently veneered with a pressable glass-ceramic (IPS e.max ZirPress, Ivoclar-Vivadent). A $5{\mu}m$ (nominal tip diameter) spherical indenter was used with a UMIS CSIRO 2000 (ASI, Canberra, Australia) nanoindenter system to test E across the exposed and polished interfaces of both specimen types. The multiple point load - partial unload method was used for E determination. All materials used were characterized using Scanning Electron Microscopy (SEM) and X - ray powder diffraction (XRD). E mappings of the areas tested were produced from the nanoindentation data. RESULTS. A significantly (P<.05) lower E value between Type-1 and Type-2 specimens at a distance of $40{\mu}m$ in the veneer material was associated with the liner. XRD and SEM characterization of the zirconia sample showed a fine grained bulk tetragonal phase. IPS e-max ZirPress and IPS e-max ZirLiner materials were characterized as amorphous. CONCLUSION. The liner between the YTZP core and the heat pressed veneer may act as a weak link in this dental multilayer due to its significantly (P<.05) lower E. The present study has shown nanoindentation using spherical indentation and the multiple point load - partial unload method to be reliable predictors of E and useful evaluation tools for layered dental ceramic interfaces.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.21 no.1
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• pp.27-37
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• 2011

The IDS/IPS(Intrusion Detection/Prevention System) has been widely deployed to protect the internal network against internet attacks. Reducing the packet inspection time is one of the most important challenges of improving the performance of the IDS/IPS. Since the IDS/IPS needs to match multiple patterns for the incoming traffic, we may have to apply the multiple pattern matching schemes, some of which use finite automata, while the others use the shift table. In this paper, we first show that the performance of those schemes would degrade with various kinds of pattern sets and payload, and then propose a hybrid multiple pattern matching scheme which combines those two schemes. The proposed scheme is organized to guarantee an appropriate level of performance in any cases. The experimental results using real traffic show that the time required to do multiple pattern matching could be reduced effectively.

• Journal of Korean Neurosurgical Society
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• v.65 no.5
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• pp.688-696
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• 2022

Objective : Transvenous embolization (TVE) via an occluded inferior petrosal sinus (IPS) in a cavernous sinus dural arteriovenous fistula (CSDAVF) is challenging, often requiring navigation of a microcatheter through resistive obstacles between the occluded IPS and shunted pouch (SP), although the reopening technique was successfully performed. We report five cases of successful access to the cavernous sinus (CS) or SP using the rigid-tipped microguidewire such as chronic total occlusion (CTO) wire aiming to share our initial experience with this wire. Methods : In this retrospective study, four patients with CSDAVF underwent five procedures using the CTO wire puncture during transfemoral transvenous coil embolization. Puncture success, shunt occlusion, and complications including any hemorrhage and cranial nerve palsy were evaluated. Results : Despite successful access through the occluded IPS, further entry into the target area using neurointerventional devices was impossible due to a short-segment stricture before the CS (three cases) and a membranous barrier within the CS (two cases). However, puncturing these structures using the rigid-tipped microguidewire was successful in all cases. We could advance the microcatheter over the rigid-tipped microguidewire for the navigation to the SP and achieved complete occlusion of the SP without complications. Conclusion : The use of the rigid-tipped microguidewire in the TVE via the occluded IPS of the CSDAVF would be feasible and safe.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.291-295
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• 2007

FTL(Fuel Test Loop) is a facility that confirms performance of nuclear fuel at a similar irradiation condition with that of nuclear power plant. FTL consists of In-Pile Test Section (IPS) and Out-Pile System (OPS). FTL construction work began on August, 2006 and ended on March, 2007. During Construction, ensuring the worker's safety was the top priority and installation of the FTL without hampering the integrity of the HANARO was the next one. Task Force Team was organized to do a construction systematically and the communication between members of the task force team was done through the CoP(community of Practice) notice board provided by the Institute. The installation works were done successfully overcoming the difficulties such as on the limited space, on the radiation hazard inside the reactor pool, and finally on the shortening of the shut down period of the HANARO. Without a sweet of the workers of the participating company of HEC(Hyundae Engineering Co, Ltd), HDEC(HyunDai Engineering & Construction Co. Ltd), equipment manufacturer, and the task force team, it is not possible to install the FTL facility within the planned shutdown period. The Commissioning of the FTL is on due to check the function and the performance of the equipment and the overall system as well. The FTL shall start operation with high burn up test fuels in early 2008 if the commissioning and licensing progress on schedule.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.6
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• pp.2881-2894
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• 2018

Cyber attacks are increasing continuously. On average about one million malicious codes appear every day, and attacks are expanding gradually to IT convergence services (e.g. vehicles and television) and social infrastructure (nuclear energy, power, water, etc.), as well as cyberspace. Analysis of large-scale cyber incidents has revealed that most attacks are started by PCs infected with malicious code. This paper proposes a method of detecting an attack IP automatically by analyzing the characteristics of the e-mail transfer path, which cannot be manipulated by the attacker. In particular, we developed a system based on the proposed model, and operated it for more than four months, and then detected 1,750,000 attack IPs by analyzing 22,570,000 spam e-mails in a commercial environment. A detected attack IP can be used to remove spam e-mails by linking it with the cyber removal system, or to block spam e-mails by linking it with the RBL(Real-time Blocking List) system. In addition, the developed system is expected to play a positive role in preventing cyber attacks, as it can detect a large number of attack IPs when linked with the portal site.

• KIPS Transactions on Computer and Communication Systems
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• v.5 no.10
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• pp.373-378
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• 2016

Recently, IPS(Indoor Positioning System) Technology has been progressing study and research, It has been studied in the fingerprinting and trilateration continuously. however because Fingerprinting and Trilateration Technology use AP(Access Point) for Positioning Calculation, Fingerprinting and Trilateration are not never had a credit positioning accuracy by using unstable RSSI in large scale. in this paper, to improve the problem about precise positioning in wide area, we introduced a concept of Sector including Cell. Sectors are not involved in each other and only fingerprinting calculation is proceed in a sector. we suggest this fingerprinting system considering efficiency and accuracy and compared to conventional fingerprinting, we demonstrated our system efficiency by mathematical techniques.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.5
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• pp.465-472
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• 2016

This study materialized an FPGA-based system to extract PCB patterns. The Printed Circuit Boards that are produced these days are becoming more detailed and complex. Therefore, the importance of a vision system to extract defects of detailed patterns is increasing. This study produced an FPGA-based system that has high speed handling for vision automation of the PCB production process. A vision library that is used to extract defect patterns was also materialized in IPs to optimize the system. The IPs materialized are Camera Link IP, pattern matching IP, VGA IP, edge extraction IP, and memory IP.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.2
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• pp.435-442
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• 2018

This study implemented an FPGA-based system to extract PCB defect patterns. The FPGA-based system can perform pattern matching at high speed for vision automation. An image processing library that is used to extract defect patterns was also implemented in IPs to optimize the system. The IPs implemented are Camera Link IP, Histogram IP, VGA IP, Horizontal Projection IP and Vertical Projection IP. In terms of hardware, the FPGA chip from the Vertex-5 of Xilinx was used to receive and handle images that are sent from a digital camera. This system uses MicroBlaze CPU. The image results are sent to PC and displayed on a 7inch TFT-LCD and monitor.