• Transactions of Materials Processing
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• v.10 no.6
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• pp.500-508
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• 2001

The integration of Rapid prototyping (RP) and Rapid Tooling (RT) has the potential for rapid net shaping of thee-dimensional parts, which have a geometrical complexity. In this study, a new R)P process, (VLM-SP), was proposed to manufacture net shapes of three-dimensional prototypes and it was shown that VLM-SP is an effective and economic process through the comparison of building time, building cost and dimensional accuracy for the test parts with the commercial RP processes ; LOM and FDM. In addition, the metal parts, which are a spanner shape and a clover punch, were produced by the plaster casting as one of RT using the prototypes of VLM-SP.

• Journal of the Korea Computer Industry Society
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• v.7 no.3
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• pp.179-184
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• 2006

many corporation introduce information system by method to maximize profit and to reduce expense within flood of information along with development of Information Technology. In this paper, construed AS-IS using UML that is an object intention methodology design tool via process of TO-BE process model design and so on to base Use Case diagram, sequence diagram, component diagram make out that do and this is Microsoft's .NET And wished to raise reusability of component and development productivity of software as that embody smaller enterprise type business administration system that .NET-based relationship extension is possible.

• The Journal of Society for e-Business Studies
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• v.8 no.4
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• pp.89-111
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• 2003

In this paper, we propose a reference model suitable for domestic situations. analyzing whether purchase processes suggested by RosettaNet can be applied to domestic industry First of all, implementation cases applied to purchase processes in the world are investigated. Second, purchase processes of a domestic manufacturer are analyzed for the RosettaNet standard application, and the processes are compared with PIP. Finally, new purchase processes and corresponding PIP documents which reflect domestic situations are proposed.

• Journal of Welding and Joining
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• v.27 no.3
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• pp.67-72
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• 2009

The flux cored arc welding (FCAW) process is one of the most frequently employed and important welding process due to high productivity and excellent workability. The process is performed either as an automated process or as a semi-automatic process. In FCAW process, welding voltage has been considered as a qualitative indication of arc length. But it is necessary to let welding operators know, maintain and manage the arc length directly by estimating and displaying it. In this study, to develop arc length estimation technique, we measured a welding circuit resistance($R_sc$) and then we calculated welding circuit voltage drop($V_sc$). Also, we measured arc peak voltage($V_ap$). By subtracting $V_sc$ from $V_arc$, we can easily calculate net arc voltage drop($V_arc$). Consequently, we suggested arc length estimating equation and basic algorithm by regressive analyzing the relationship between net arc voltage drop($V_arc$) and real arc length(Larc) measured by high speed camera. Therefore, arc length can be predicted by just monitoring welding current and voltage.

• Journal of Information Processing Systems
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• v.15 no.6
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• pp.1472-1488
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• 2019

Critical elements in the China's Lunar Exploration reside in that the lunar rover travels over the surrounding undetermined environment and it conducts scientific exploration under the ground control via teleoperation system. Such an interplanetary transportation mission teleoperation system belongs to the ground application system in deep space mission, which performs terrain reconstruction, visual positioning, path planning, and rover motion control by receiving telemetry data. It plays a vital role in the whole lunar exploration operation and its so-called trustworthy evidence must be assessed before and during its implementation. Taking ISO standards and China's national military standards as trustworthy evidence source, the net assessment model and net assessment method of teleoperation system are established in this paper. The multi-dimensional net assessment model covering the life cycle of software is defined by extracting the trustworthy evidences from trustworthy evidence source. The qualitative decisions are converted to quantitative weights through the net assessment method (NAM) combined with fuzzy analytic hierarchy process (FAHP) and entropy weight method (EWM) to determine the weight of the evidence elements in the net assessment model. The paper employs the teleoperation system for interplanetary transportation as a case study. The experimental result drawn shows the validity and rationality of net assessment model and method. In the final part of this paper, the untrustworthy elements of the teleoperation system are discovered and an improvement scheme is established upon the "net result". The work completed in this paper has been applied in the development of the teleoperation system of China's Chang'e-3 (CE-3) "Jade Rabbit-1" and Chang'e-4 (CE-4) "Jade Rabbit-2" rover successfully. Besides, it will be implemented in China's Chang'e-5 (CE-5) mission in 2019. What's more, it will be promoted in the Mars exploration mission in 2020. Therefore it is valuable to the development process improvement of aerospace information system.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.4
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• pp.896-907
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• 1995

Titanium 6242(.alpha. + .betha.) alloy has a good strength/weight ratio and is used for aircraft components such as engine disks and compressor blades. When this material is forged at an elevated temperature, the process parameters should be carefully controlled because the process window of this material is quite narrow. In the present investigation, a rigid-thermoviscoplastic finite element method is used to predict the deformation behavior and temperature/strain distributions in an engine disk during near-net shape hot forging. The purpose of the investigation is to obtain a proper ram speed profile, assuming the hydraulic press used in the forging is capable of varying ram speed during loading. In result, it was found that the ram speed at constant strain-rate of 0.5/sec shows a sound deformation behavior, a relatively uniform deformation and a good temperature distribution. This information is also valuable in predicting resulting microstructures in the disk.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.2
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• pp.322-330
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• 1994

SIBs(Service Independent Building block) are defined in CCITT advanced intelligent network concept model for supporting various services in the future. This paper describes the protocol modeling and verification for basic call process SIB. For modeling, we use Petri Net and verify this modeling by analyzing reachability tree of Petri Net. Results of this paper should be used for design and implementation of basic call process SIB.

• The Journal of the Acoustical Society of Korea
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• v.22 no.2E
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• pp.49-55
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• 2003

The modified neural net pattern recognition equations were attempted to apply to speech recognition. The proposed method has a dynamic process of self-organization that has been proved to be successful in recognizing a depth perception in stereoscopic vision. This study has shown that the process has also been useful in recognizing human speech. In the processing, input vocal signals are first compared with standard models to measure similarities that are then given to a process of self-organization in neural net equations. The competitive and cooperative processes are conducted among neighboring input similarities, so that only one winner neuron is finally detected. In a comparative study, it showed that the proposed neural networks outperformed the conventional HMM speech recognizer under the same conditions.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.501-502
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• 2006

The present investigation has been performed on full densification behavior and mechanical property of the powder injection molded Fe-8wt%Ni nanoalloy powder. The net shaping process of the nanopowder was conducted by powder injection molding (PIM) process. The key-process for fabricating fully densified net-shaped nanopowder by pressureless sintering is an optimal control of agglomerate size of nanopowder. Enhanced mechanical property of PIMed Fe-Ni nanopowder is explained by grain refinement and microstructural uniformity.

• Journal of Korean Institute of Industrial Engineers
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• v.23 no.4
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• pp.669-686
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• 1997

In this research, an object-oriented Petri net model for representing a flexible process plan is proposed, which is hierarchically multi-faceted for supporting planning, scheduling, and shop floor control functions. The multi-faceted process plan model consists of the following: a) an object model which represents on object-oriented data model, b) a static model which represents a process flow model with process alternatives, and c) a dynamic model which represents a process activity model with resources alternatives, of a flexible process plan. Petri nets allow the static and the dynamic process plan models to be represented in a unified formalism with an ease of model transformation. The multi-faceted process plan model suggested in this paper, is illustrated with a prismatic port in comprehensive detail.