• The Journal of the Acoustical Society of Korea
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• v.28 no.8
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• pp.796-805
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• 2009

In this paper, a fabrication process for PZT preform of 1-3 type piezo-composite were studied using powder injection molding (PIM). The viscosity and the Pressure-Volume-Temperature (PVT) characteristics of the fabricated PZT feedstock were analyzed. The filling patterns, pressure, temperature distributions, and forming defects of the preform were analyzed with 3D TIMON commercial packages during PIM process. Also the fabrication conditions and the delivery system of the preform were optimized during the entire PIM process. Based on the simulated results, the preform having uniform distributions of the PZT rod was fabricated with the PIM process.

• Transactions of Materials Processing
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• v.14 no.6 s.78
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• pp.570-576
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• 2005

Powder Injection Molding(PIM) has recently been recognized as an advanced manufacturing technology for low-cost mass production of metal or ceramic parts of complicated geometry With this regards, design technology of dental scaler tip PIM mold, which has complex shape and small core pin (diameter=0.6mm), with the help of computer-aided analysis of powder injection molding process was developed. Computer-aided analysis for dental scaler tip mold was implemented by finite element method with non-Newtonian fluid, modified Cross model viscosity, PvT data of powder/binder mixture. Compter-aided analysis results, such as filling pattern, weldline formation, air vent position prediction were compared with experimental result, and eventually have been shown good agreement. The core pin (diameter=0.6mm) deflection analysis of dental scaler tip PIM mold during PIM filling process was also investigated before mold fabrication.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.499-500
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• 2006

With the capability of net shaping for complex 3D geometry, powder injection molding (PIM) is widely used for automotive parts, electronics and medical industry. In this study, an ultrasonic dental scaler tip produced by machining process was redesigned for the PIM process. An injection mold was designed and machined to produce the dental scaler tip by the PIM process.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.33 no.2
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• pp.235-242
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• 2023

ORAM(Oblivious RAM) is an algorithm that defends side channel attacks when the user uses an untrusted server or hardware. ORAM defends against leaks of information by hiding data access patterns. However, ORAM is not in practical use because as ORAM reinforces hardware security, it also has a severe disadvantage in processing speed. In this paper, we suggest using newly introduced hardware, PIM (Process In Memory), to accelerate ORAM and use it practically.

• The KIPS Transactions:PartD
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• v.16D no.3
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• pp.381-394
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• 2009

As a technique to enhance reusability for the created artifacts in software modeling process, the model driven method such like MDA has been applied. Unfortunately, the hierarchical and systematic MDA based development technique using UML is poor yet. This causes the problem that the MDA modeling with high consistency and reusability based on MDA metamodel is not being realized. To solve this problem, this paper proposes a MDA (PIM/PSM) component modeling technique using 2+1 view integrated metamodel. At first, the meta-architecture view model which can represents development process view and MVC view is defined. Then, the hierarchical integrated metamodels per view are addressed separately for modeling process and MVC at metamodel level on the hierarchy of the defined meta-architecture view model. These metamodels are defined hierarchically by layering the modeling elements in PIM and PSM pattern for UML models and GUI models. Appling the proposed metamodel to an ISMS application system, it is shown as a component modeling case study based on MDA. Through this approach, we are able to perform a component model with consistency and hierarchy corresponding to development process and MVC way. Accordingly, this may improve more independence and reusability of model.

• Journal of Powder Materials
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• v.5 no.4
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• pp.258-264
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• 1998

The initial sintering behaviour of the powder injection molded (PIMed) W-l5wt%Cu nanocomposite powder was investigated. The W-Cu nanocomposite powder was produced by the mechanochemical process consisting of high energy ball-milling and hydrogen reduction of W blue powder-CuO mixture. Solid state sintering of the powder compacts was conducted at $1050^{\circ}C$ for 2~10 hours in hydrogen at mosphere. The sintering behaviour was examined and discussed in terms of microstructural developments such as W-Cu aggregate formation, pore size distribution and W grain growth. The volume shrinkage of PIM specimen was slightly larger than that of PM(conventional PM specimen), being due to fast local densification in the PIM. Remarkable decrease of carbon and oxygen in the PIM enhanced local densification in the early stage of solid state sintering process with eliminating very fine pores less than 10 nm. In addition, such local densiflcation in the PIM is presumably responsible for mitigating of W-grain growth in the initial stage.

• Journal of the Korea Society of Computer and Information
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• v.17 no.6
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• pp.131-144
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• 2012

MDD is suitable to satisfy constraints of development of mobile applications. So, there are various studies about applying MDD to the developments of mobile application but systematic development methods about UML profile for PIM/PSM of mobile applications and model transformation techniques are needed. This paper suggests that a development technique about UML profile for PIM/PSM of mobile applications and a model transformation techniques with the profiles. We classify stereotypes by the characteristics of mobile application to compose profiles and suggest development guidelines of profiles for PIM/PSM. On the suggested model transformation process, the PIM with the profiles is transformed to the intial PSM with the mapping rules and the PSM is transformed to the refined PSM with templates which reflected detailed information of a mobile platform. We developed a location based service mobile application with the suggested techniques on the Android platform and compared with other techniques to validate usefulness of the suggested techniques.

• Korean Journal of Metals and Materials
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• v.49 no.1
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• pp.32-39
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• 2011

The present investigation was performed on the die compaction and sintering behavior of Fe micro-nano mixed powder with a mixed binder for powder injection molding. Warm die compaction of the feedstock for simulation of the static injection molding process was conducted using a cylindrical mold of 10 mm diameter at $100^{\circ}C$ under 4MPa. The die compaction of the micro-nanopowder feedstock underwent a uniform molding behavior showing a homogeneous distribution of nanopowders among the micropowders without porosity and distortion. After debinding, the powder compact maintained a uniform structure without crack and distortion, leading to a high green density of 64.2% corresponding to the initial powder loading of 65%. The sintering experiment showed that the micro-nanopowder compact underwent a near full and isotropic densification process during sintering. It was observed that the nanopowders effectively suppressed the growth of micropowder grains during densification process. Conclusively, the use of nanopowder for PIM feedstock might provide a new concept for processing a full density PIM parts with fine microstructure.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.83-84
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• 2006

Due to the capability of net shaping for complex 3D geometry, powder injection molding (PIM) is widely used for automotive parts, electronics and medical industry. In this study, an ultrasonic dental scaler tip produced by machining process was redesigned for the PIM process. An injection mold was designed and manufactured to produce the dental scaler tip by the PIM process.

• Transactions of Materials Processing
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• v.12 no.6
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• pp.521-528
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• 2003

Powder injection molding (PIM) uses the shaping advantage of injection molding but is applicable to metals and ceramics. This process combines a small quantity of polymer with an inorganic powder to form a feedstock that can be molded. After shaping, the polymeric binder is extracted and the powder is sintered, often to near-theoretical densities. According1y, PIM delivers structural materials in a shaping technology previously restricted to polymers. The process overcomes the shape limitations of traditional powder compaction, the costs of machining, the productivity limits of isostatic pressing and slip casting, and the defect and tolerance limitations of conventional casting. Since 1980s when major attention was given to PIM process, it has been widening the application area from small parts with complex shape and tailored properties to structural parts requiring strength and ductility as in automotive, military and medical industries.