• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.41-46
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• 2003

The objective of this paper is to present a methodology for automatically balancing multi-cavity injection molds with the aid of flow simulation. After the runner and cavity layout has been designed, the methodology adjusts runner and gate sizes iteratively based on the outputs of flow analysis. This methodology also ensures that the runner sizes in the final design are machinable. To illustrate this methodology, an example is used wherein a 3-cavity mold is modeled and filling of all the cavities at the same time is achieved. Based on the proposed methodology, a multicavity mold with identical cavities is balanced to minimize overall unfilled volume among various cavities at discrete time steps of the molding cycle. The example indicates that the described methodology can be used effectively to balance runner systems for multi-cavity molds.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.2
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• pp.106-114
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• 2010

We proposed an unified design methodology and verification platform for giga-scale System on Chip (SoC). According to the growth of VLSI integration, the existing RTL design methodology has a limitation of a production gap because a design complexity increases. A verification methodology need an evolution to overcome a verification gap. The proposed platform includes a high level synthesis, and we develop a power-aware verification platform for low power design and verification automation using it's results. We developed a verification automation and power-aware verification methodology based on control and data flow graph (CDFG) and an abstract level language and RTL. The verification platform includes self-checking and the coverage driven verification methodology. Especially, the number of the random vector decreases minimum 5.75 times with the constrained random vector algorithm which is developed for the power-aware verification. This platform can verify a low power design with a general logic simulator using a power and power cell modeling method. This unified design and verification platform allow automatically to verify, design and synthesis the giga-scale design from the system level to RTL level in the whole design flow.

• Transactions on Electrical and Electronic Materials
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• v.15 no.3
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• pp.149-154
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• 2014

A new CMOS analog design methodology using an independently optimized self-cascode (SC) is proposed. This idea is based on the concept of the dual-workfunction-gate MOSFETs, which are equivalent to SC structures. The channel length of the source-side MOSFET is optimized, to give higher transconductance ($g_m$) and output resistance ($r_{out}$). The highest $g_m$ and $r_{out}$ of the SC structures are obtained by independently optimizing the channel length ratio of the SC MOSFETs, which is a critical design parameter. An operational amplifier (OPAMP) with the proposed design methodology using a standard digital $0.18-{\mu}m$ CMOS technology was designed and fabricated, to provide better performance. Independently $g_m$ and $r_{out}$ optimized SC MOSFETs were used in the differential input and output stages, respectively. The measured DC gain of the fabricated OPAMP with the proposed design methodology was approximately 18 dB higher, than that of the conventional OPAMP.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.3
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• pp.573-577
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• 2009

Piezoresistive pressure sensor have become the successfully-commercialized MEMS product and the related technologies have been well developed over the past decades. Regarding the design methodology, however, the coupled-physics FEM analyses of the transducer itself and the signal-processing circuitry design based on the conventional EDA are separated and both of the analyses were sequentially processed for the full design of the pressure sensor. For the fast and effective R&D, new design methodology is proposed in this paper where the FEM results are linked to the EDA environment and therefore most of the design works can be done in the EDA environments, which means the time-consuming FEM analyses can be minimized. In order to verify the proposed approach, a typical piezoresistive pressure sensor having the silicon diaphragm and piezoresistors was modeled and analyzed based on the proposed methodology. The verification results showed that the simulated results were matched well with the measured data within the 7% difference while the simulation time was reduced less than 5% compared to the conventional methodology. Through the proposed approach, various types of the piezoresistive pressure sensors can be developed in more effective way.

• International Journal of Control, Automation, and Systems
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• v.5 no.5
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• pp.515-525
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• 2007

In this paper, we develop a co-design methodology of stochastic optimal controllers and network parameters that optimizes the overall quality of control (QoC) in networked control systems (NCSs). A new dynamic model for NCSs is provided. The relationship between the system stability and performance and the sampling frequency is investigated, and the analysis of co-design of control and network parameters is presented to determine the working range of the sampling frequency in an NCS. This optimal sampling frequency range is derived based on the system dynamics and the network characteristics such as data rate, time-delay upper bound, data-packet size, and device processing time. With the optimal sampling frequency, stochastic optimal controllers are designed to improve the overall QoC in an NCS. This co-design methodology is a useful rule of thumb to choose the network and control parameters for NCS implementation. The feasibility and effectiveness of this co-design methodology is verified experimentally by our NCS test bed, a ball magnetic-levitation (maglev) system.

• Industrial Engineering and Management Systems
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• v.3 no.2
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• pp.140-150
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• 2004

Repetitive stress injury at the wrist has been reported as a common injury among visual display terminal (VDT) users (i.e., computer users). Adjusting a VDT workstation (computer table and chair) to maintain a correct seated posture while operating a keyboard is perhaps the most frequently recommended preventive solution. This paper proposes an analytical design methodology based on ergonomic design principles for recommending appropriate VDT workstation settings and layout of individual computer accessories on the computer table. The proposed design methodology consists of two interrelated phases: (1) determination of VDT workstation settings, and (2) design of computer accessories layout. Based on the information about the VDT user, dominant task to be performed, typing skill, and degrees of physical and visual interactions between the user and computer accessories, adjustment and layout solutions are recommended to allow having a correct seated posture while minimizing both physical and visual movements. The results from an experiment show that when adjusting the workstation and locating the computer accessories according to the recommendations given by the proposed design methodology, the user's hand movements can be significantly reduced.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.2
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• pp.69-75
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• 2006

This paper deals with the optimum design solution on reduction of torque ripple for a Synchronous Reluctance Motor with concentrated winding using response surface methodology. The coupled Finite Elements Analysis (FEA) & Preisach model have been used to evaluate the nonlinear solution. Comparisons are given with characteristics of a SynRM according to the stator winding, slot number, open width of slot, slot depth, teeth width variation in concentrated winding SynRM, respectively. This paper presents an optimization procedure using Response Surface Methodology (RSM) to determine design parameters for reducing torque ripple. RSM has been achieved to use the experimental design method in combination with finite Element Method (FEM) and well adapted to make analytical model for a complex problem considering a lot of interaction of design variables. Moreover, Sequential Quadratic Problem (SQP) method is used to solve the resulting of constrained nonlinear optimization problem.

• Journal of Korean Institute of Industrial Engineers
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• v.13 no.2
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• pp.47-57
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• 1987

The main purpose of this paper is to design a simple interactive software system for planning activities, called APS. We discuss the importance of informal and formal specifications of the system design, and survey a number of promissing design methodologies. To design APS, we present a methodology based upon the hierarchical decomposition of the system, and illustrate the methodology as applied to the design of an activity planning system.

• Journal of Digital Convergence
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• v.15 no.11
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• pp.447-454
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• 2017

Human desires start from the factors that make up the basic living environment. The development model of the safety guidelines will start from a sense of departure from collective psychology and systemic environment, at the time of inducing threats to threats. The design and methodology of the safety guidelines should be drawn up repeatedly by the sequence of iterative models, and the design methodology should be designed in the chronological order of the public services through the methodology of service design methodology. Various and complex threats attempt to derive insights from the user's perspective and to derive insight into the development of the safety guidelines and the sophistication of the user experience, and to extract insights from the perspective of a user's perspective and supervision model. This derived insight can be implemented as a multi-dimensional service model derived from the same problem consciousness methodology.

• Journal of Korea Multimedia Society
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• v.22 no.2
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• pp.292-298
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• 2019

Mobile-based software development methodology has been vigorously researched from using object-oriented development methodology and component-based development methodology previous structural developing methodology. There are two types of OS in mobile platform which are android and iOS. There is a problem that the application to be developed is developed depending on the device type. To resolve this problem, first, the system structure and design method should be managed effectively. Second, a basic design guide that can be commonly adapted to the each project is required. In this paper, we define a mobile cross platform meta model based on MDA-development methodology, focusing on reusability, portability and interoperability about non - dependent part of the mobile platform. If the proposed meta-model is applied to manage the related information and all the types of Mobile-Apps become available through independent mobile app development process, henceforward, it will be much of help establishing formulaic mobile-app developmental methodology.