• Korean Journal of Computational Design and Engineering
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• v.10 no.5
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• pp.328-338
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• 2005

CAD systems are routinely used by designers for creating part geometries. Interfaces to CAE/CAM systems are also commonplace enabling the FEA-based design optimization and the rapid fabrication of the designed part. However, conventional CAD systems have thus far focused on objects with homogeneous interior. Two recent advances--use of heterogeneous objects such as Functionally Graded Materials (FGM) in parts and Layered Manufacturing Technology (LMT)--have brought to the forefront the need for CAD systems to support the creation of geometry as well as the graded material inside. We first describe the need and the components of such a CAD system for heterogeneous objects. A prototype CAD system is then described with one specific example (thermal barrier type FGM, pressure vessel) in order to illustrate the use of the implemented CAD system. The implemented system is manually integrated with FEA tools for optimal design. Our ongoing work involves the automation of the integration with FEA tools.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.8 s.227
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• pp.1159-1165
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• 2004

This paper describes fabrication of a micro cell counter integrated with an oxygen micropump and counting experiment with Sephadex G-25 beads ($70{\sim}100\;{\mu}m$). The pumping part consisted of a microheater, catalyst (manganese dioxide) enveloped with paraffin, hydrogen peroxide, and microchannel, and the counting part consisted of collimated light, a microwindow, and a phototransistor including an external circuit. The micropump generated oxygen gas by decomposing hydrogen peroxide with manganese dioxide, which was initiated by melting the paraffin with the microheater, and pumped beads in the microchannel. When the beads passed the microwindow, they shaded the collimated light and changed the illumination on the phototransistor, which caused the current variation in the circuit. The signals, according to the bead size, reached up to 22 mV with noise level of 2 mV during 50 seconds and the numbers of peaks were analyzed by magnitude.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3089-3091
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• 1999

To control IWR-III Biped Waking Robot, those complex modules are necessary that concurrent control multi-axes servo motors, PID & Feedforward gain tuning, initial value calibration, display current status of system, user interface for emergency safety and three-dimensional rendering graphic visualization. It is developed for various-type gait $data^{[1]}$ and for control modes (i.e open/closed loop and pulse/velocity/torque control) that Integrated Control Enviroment with GUI( Graphic User Interface) consist of time-buffered control part using MMC (Multi-Motion Controller) and 3D simulation part using DirectX graphic library.

• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.1
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• pp.83-88
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• 2019

Structural analysis remains as an essential part of any integrated civil engineering system in today's rapidly changing computing environment. Even with enormous advancements in capabilities of computers and mobile tools, enhancing computational efficiency of algorithms is necessary to meet the changing demands for quick real time response systems. The finite element method is still the most widely used method of computational structural analysis; a robust, reliable and automated finite element structural analysis module is essential in a modern integrated structural engineering system. To be a part of an automated finite element structural analysis, an efficient adaptive mesh generation scheme based on R-H refinement for the mesh and error estimates from representative strain values at Gauss points is described. A coefficient that depends on the shape of element is used to correct overly distorted elements. Two simple case studies show the validity and computational efficiency. The scheme is appropriate for nonlinear and dynamic problems in earthquake engineering which generally require a huge number of iterative computations.

• Journal of Korean Institute of Industrial Engineers
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• v.25 no.3
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• pp.298-309
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• 1999

In this study, we attempt to solve the loading and scheduling problems of an FMS in an integrated manner. We propose an integrated approach and its solution methodologies which can fully exploit the flexibility of an FMS effectively and make decisions about tool allocation, machine selection, and job sequencing simultaneously. The proposed approach consists of two main modules : 'schedule generating module' which makes partial schedules and 'tool-allocation checking module' which investigates the feasibility of tool-allocation for unscheduled tasks. Utilizing two interacting modules, we can finally settle the loading and scheduling problems. Experimental results show that in most cases the proposed integrated approach outperforms existing hierarchical approaches in the scheduling performance and the computational time required. In addition to that, the difference between the two approaches tends to increase when the number of part types and the number of alternative machines increase and the tool constraints become tight. To conclude, the experimental results show that the proposed approach is a viable one for solving practical problems.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.9
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• pp.1668-1673
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• 2011

Recent power industries are to be progressed as moving into horizontal markets and expanding of competitive systems through promoting SmartGrid. In these environments, the information on power consumers leads to establish a part of power markets through active and real-time participations instead of participating it as a passive manner presented by a vertical integration. Also, such information should be established as a way that effectively reflects changes and market behaviors occurred in power market participants. Therefore, in this study, a method that develops consumer information models, performs integrated managements, implements registration and distribution, and forms integrated management centers is presented to commonly use the consumer information according to the change in the environment of power industries.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.352-361
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• 1998

The post-processing modules are parts of an integrated system for reinforced concrete structures. This modules are composed of two modules: member design module and calculation report module. The purpose of this paper is to develope modules that increase efficiency and usefulness of an integrated system used reinforced concrete structures design. The development of post-processing modules is necessary for user to design reinforced concrete structures conveniently and quickly. This modules are connected with central database for the benefit of storing amount of input/output data and being used system with little effort. Post-processing modules used Object-Oriented concepts and techniques include identity, classification, polymorphism, and inheritance. Member design module automatically converts no good members into satisfied members by changing section size or reinforcement bar arrangement. This module can be operated both independent member design modules with user input and a part of integrated system with database input. If user operates member design module, calculation report module is created automatically.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.515-519
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• 2002

As the number of the company to acquire the certifications of ISO 9001/1400, OHSAS 18001(not official standard) is increasing, it is needed to construct a integrated business management system for the efficient application of the certifications. In this circumstances the integrated construction of the SHE & Q system so called, for Safety, Health, Environment and Qualify can take a part for the communication in the customer, the company convenience and the interested parties(the worker. the supplier and the provider). In case that each certification systems are integrated, the problems of the redundancy in the management processes and the conflicting demands are able to be solved and the efficiency of the restricted management resources fan be raised as the complexity of the redundancies in the certification management is simplified. This paper deals with the integrated strategies, its convenience and its expecting merit and demerit for the efficient application of the certification parties haying the various characters.

• Journal of Mechanical Science and Technology
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• v.18 no.8
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• pp.1349-1357
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• 2004

Computer-Aided Inspection Planning (CAIP) is the integration bridge between CAD/CAM and Computer Aided Inspection (CAI). A CAIP system for On-Machine Measurement (OMM) is proposed to inspect the complicated mechanical parts efficiently during machining or after machining. The inspection planning consists of Global Inspection Planning (GIP) and Local Inspection Planning (LIP). In the GIP, the system creates the optimal inspection sequence of the features in a part by analyzing the various feature information such as the relationship of the features, Probe Approach Directions (PAD), etc. Feature groups are formed for effective planning, and special feature groups are determined for sequencing. The integrated process and inspection plan is generated based on the sequences of the feature groups and the features in a feature group. A series of heuristic rules are developed to accomplish it. In the LIP of Part II, the system generates inspection parameters. The integrated inspection planning is able to determine optimum manufacturing sequence for inspection and machining processes. Finally, the results are simulated and analyzed to verify the effectiveness of the proposed CAIP.

• Journal of Korean Institute of Industrial Engineers
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• v.21 no.1
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• pp.85-101
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• 1995

Automated Guided Vehicles(AGVs) are widely used in computer integrated manufacturing(CIM) systems for material handling purposes. Although automated guided vehicles provide higher levels of flexibility and computer integrability, the installations are limited in number and one of the critical reasons lies in the complexity involved in the operation. The main objective of this research is to alleviate this problem by proposing efficient integrated operational control methods for AGV-based CIM systems. Particularly, this research is concerned with the mixed problem of dispatching automated guided vehicles and scheduling machines operation. The proposed dynamic heuristic algorithm uses various priority schemes and relevant information concerning the load of the system, the status of queues, and the position of AGVs in the scheduling process. The scheduling decision process is hierarchical in the sense that different decision criteria are applied sequentially to identify the most appropriate part to be served. This algorithm consists of two sections, the section of part selection by AGVs for the next service whenever an AGV completes the current assignment, and the section of part selection by machines for next service whenever a machine completes the current operation. The proposed algorithm has been compared with other scheduling schemes using the performance measure of mean flow-time and mean tardiness. Simulation results indicate that the proposed algorithm can reduce the mean flow-time and mean tardiness significantly.