• Journal of Powder Materials
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• v.9 no.4
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• pp.251-260
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• 2002

In the viscosity measurement of PIM feedstock, slip correction methods require a number of experiments and produce a high level of error. In this study, a rotational rheometer with a parallel-discs configuration having different surface roughness was tried to minimize the effect of the slip phenomenon. Disc surface was prepared in 3 different roughness conditions - a smooth and 2 roughened surfaces. Results with the roughened surfaces were compared with the results obtained with a slip correction method. Relationship between powder characteristics such as size and shape and a surface roughness of the disc was examined for feedstock of 4 different powders with a same binder. As results, the effect of the slip phenomenon could be sufficiently minimized on the roughened surface in most cases. However, the effect of the slip phenomenon could not be sufficiently minimized for feedstock of a round-particular-shape powder and in the case of very narrow gap size.

• Journal of Powder Materials
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• v.9 no.4
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• pp.211-217
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• 2002

It is well known that the powder injection molding(PIM) process can overcome 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. Increasing demands from industry for not only the dimensional accuracy nut mechanical strength in PIMed parts have had much effort focused on the investigation of mechanical properties of mechanical strength in PIMed parts have had much effort focused on the investigation of mechanical properties of sintered parts formed with high-strength metallic powders. The 17_4 PH $10\mu{m}$ were injection-molded into flat tensile specimens. Sintering of the compacts was carried out at the various temperatures ranging from 900 to $1350^{\circ}C$. Sintering behavior of the compacts and tensile properties of sintered specimens were investigated.

• Structural Engineering and Mechanics
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• v.54 no.4
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• pp.623-648
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• 2015

A numerical approach is presented for the analysis of the forced vibration of a rigid surface foundation with arbitrary shape. In the analysis, the foundation is discretized into a number of sub squaree-lements. The dynamic response within each sub-element is described by the Green's function, which is obtained by the Fourier-Bessel transform and Precise Integration Method (PIM). Incorporating the displacement boundary condition and force equilibrium of the foundation, it obtains a system of linear algebraic equation in terms of the contact forces within each sub-element. Solving the equation leads to the desired dynamic impedance functions of the foundation. Numerical results are obtained for foundation not only with simple geometrical configurations, such as rectangular and circular foundation, but also the case of irregularly shaped foundation. Several comparisons between the proposed approach and other methods are made. Very good agreement is reached. Also, parametric studies are carried out on the dynamic response of foundation. Addressed in this study are the effects of Poisson's ratio, material damping and contact condition of soil-foundation interface. Several conclusions are drawn the significance of the factors.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07b
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• pp.436-438
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• 2005

모델 기반 아키텍처 (Model Driven Architecture, MDA)는 플랫폼 독립적인 모델로부터 변환 규칙을 이용하여 특정 플랫폼 용 모델을 생성하는 소프트웨어 자동화 기술로 각광을 받고 있다. EJB(Enterprise JavaBeans)는 컴포넌트 기반의 분산 컴퓨팅을 위한 아키텍처로써 Java 기반 어플리케이션 개발에서 가장 널리 사용되는 개발 플랫폼이다. 기존의 PIM에서 EJB 용 PSM으로 변환 규칙에 대한 연구는 아직 미흡하고 체계적이지 못하다. 본 논문에서는 PIM 의 구조적인 구성요소와 EJB 용 PSM 의 구성요소를 비교 분석하여 변환 규칙을 정의한다. EJB 어플리케이션 개발을 위해 제안된 변환 규칙을 적용한다면 모델간의 대응관계를 효율적으로 표현 할 수 있기 때문에 이들간의 일관성과 추적성을 높일 수 있고 제품의 생산성, 유지보수성을 높일 수 있다.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07b
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• pp.325-327
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• 2005

컴포넌트는 컴포넌트 기반 개발(Component Based Development, CBD)기술에서 재사용되는 기본 단위로서 OOP(Object Oriented Programming, OOP)의 객체보다 상대적으로 큰 단위의 기능성을 제공하며 재사용성이 뛰어나다. 모델 기반 아키텍처(Model Driven Architecture, MDA)는 모델들 간의 다양한 변환(Transformation)을 활용하여 어플리케이션 개발을 자동화하는 새로운 패러다임으로서 소프트웨어의 생산성을 향상시킨다. 그러나 MDA 는 컴포넌트와 같은 어플리케이션들 간의 공통성과 가변성을 활용한 재사용성을 직접적으로 지원하지는 않는다. 본 논문에서는 CBD 와 MDA 의 장점과 한계점을 알아보고 서로의 단점을 보완할 수 있도록 컴포넌트 PIM 과 컴포넌트 기반의 MDA 공학 프로세스를 제안한다. 제안된 컴포넌트 PIM 과 프로세스를 이용하면 어플리케이션들 간의 공통성과 가변성을 이용한 뛰어난 재사용성과 자동화를 통한 생산성의 ,향상 및 높은 유지보수성을 가질 수 있다.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.32-33
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• 2006

Processing and properties of high power piezoelectric transformer (PT) fabricated by PIM with nano-sized piezoelectric powders are demonstrated. The high power characteristics of a PMed dome-shaped PT were examined by the lighting test for a 55watt PL lamp. The 55watt PL lamp was successfully driven by the PIMed PT with sustaining efficiency higher than 98%. The transformer with ring/dot area ratio of 2.1 exhibited the maximum properties in terms of output power, efficiency and temperature stability.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.270-274
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• 2005

The capability of net shaping for complex 3-D geometry, powder injection molding(PIM) is widely used for parts in the field of automotives, electronics and medical industry. Powder injection mold design for dental scaler tip, a component of medical appliance, was presented. In comparison with conventional machining process, powder injection molding has many advantages, specially in price and dimensional stability, for molding dental scaler tip. Product design and mold design for dental scaler tip was presented. Short shot experiment with scaler tip PIM mold and several defect (flash etc.) during injection molding process was discussed.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.123.2-123.2
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• 2013

Etching endpoint detection with plasma impedance monitoring (PIM) is demonstrated for small area dielectric layers inductive coupled plasma etching. The endpoint is determined by the impedance harmonic signals variation from the I-V monitoring system. Measuring plasma impedance has been examined as a relatively simple method of detecting variations in plasma and surface conditions without contamination at low cost. Cluster analysis algorithm is modified and applied to real-time endpoint detection for sensitivity enhancement in this work. For verification, the detected endpoint by PIM and real-time cluster analysis is compared with widely used optical emission spectroscopy (OES) signals. The proposed technique shows clear improvement of sensitivity with significant noise reduction when it is compared with OES signals. This technique is expected to be applied to various plasma monitoring applications including fault detections as well as end point detection.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04d
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• pp.40-42
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• 2003

We implement a 3D virtual conference using IPv6 multicast protocol suites. PIM-SM(Protocol Independent Multicast-Sparse Mode) is chosen for multicast. To provide users with the virtual reality that they are actually participating in an academic conference, 3D interface is built on VRML. Various multicast activities such as join/leave of a user into/out of sessions are represented by enter/exit of corresponding avatar to maximize the "sense of presence."nce."quot;

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.04a
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• pp.36-37
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• 2006