• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.101-106
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• 2006

Balance shaft has a key role in reducing a engine vibration in a vehicle and widely applied for current models. Since balance shaft module consists many sub-component and each part has its own operational characteristics, some different analysis backgrounds should be integrated into one sub-part in balance shaft module and this is the main obstacles in making a design process. Moreover, the balancing shaft is rotating in high speed and such condition requires large safety factors in a design process owing to a lot of unexpected problems with the overwhelming rotation. Balance shaft is the core-component generating the intended unbalance as well as cancelling the unbalance force or moment by the engine module. So, the balance shaft should meet the high fatigue resistance not to mention of NVH performance. In this paper, a design strategy focused on balance shaft is developed to build a optimal model considering a engine vibration. Putting the unbalance mass distribution as main design parameter, some candidate model is verifed with structural and fatigue analysis and most appropriate model is proposed here.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.393-398
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• 2007

Balance shaft has a key role in reducing a engine vibration in a vehicle and widely applied for current models. Since balance shaft module consists many sub-component and each part had its own operational characteristics, some different analysis background should be integrated into one sub-part in balance shaft module and this is the main obstacles in making a design process. Moreover, the balancing shaft rotating in high speed and such condition requires large safety factors in a design process owing to a lot of unexpected problems with the overwhelming rotation. Balance shaft is the core-component generating the intended unbalance as well as canceling the unbalance force or moment by the engine module. So, the balance shaft should meet the high fatigue resistance not to mention of NVH performance. In this paper, a design strategy focused on balance shaft is developed to build a optimal model considering a engine vibration. Putting the unbalance mass distribution as main design parameter, some candidate model is verified with structural and fatigue analysis most appropriate model is proposed here.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.139-141
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• 2006

Quantum-dot Cellular Automata (QCA) is one of the most promising next generation nano-electronic devices which will inherit the throne of CMOS which is the domineering implementation technology of large scale low power digital systems. In late 1990s, the basic operations of the QCA cell were already demonstrated on a hardware implementation. Also, design tools and simulators were developed. Nevertheless, its design technology is not quite ready for ultra large scale designs. This paper proposes a new approach which enables the QCA designs to inherit the verification methodologies and tools of CMOS designs, as well. First, a set of disciplinary rules strictly restrict the cell arrangement not to deviate from the predefined structures but to guarantee the deterministic digital behaviors. After the gate and interconnect structures of the QCA design are identified, the signal integrity requirements including the input path balancing of majority gates, and the prevention of the noise amplification are checked. And then the digital logic is extracted and stored in the OpenAccess common engineering database which provides a connection to a large pool of CMOS design verification tools. Towards validating the proposed approach, we designed a 2-bit QCA adder. The digital logic is extracted, translated into the Verilog net list, and then simulated using a commercial software.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.3
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• pp.278-285
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• 1999

This paper utilizes the method of Q-parameterization control to design a controller which solves the problem of imbalance in magnetic bearing systems. There are two methods to solve this problem using feedback controal. The first method is to compensate for the imbalance forces by generating opposing forces on the bearing surface (imbalance compensation). The second method is to make the rotor rotate around its axis of inertia (automatic balancing);in this case no imbalance forces will be generated. In this paper we deal with only imbalance compensation. The free parameter of the Q-parameterization controller is chosen such that these goals are achieved. After the introduction of a model of the magnetic bearing system, we explain the Q-parameterization controller design of the magnetic bearing system with emphasis on the rejection of sinusoidal disturbance for imbalance compensation design. The design objectives are formulated as a linear equations in the controller free paramete Q. Finally, simulation and experimental results are presented and showed the robustness and effectiveness of the proposed controllers.

• Journal of People, Plants, and Environment
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• v.23 no.4
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• pp.387-398
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• 2020

Background and objective: Land vacancy is a persistent issue in most urban areas in the United States, yet few case studies have examined how vacant lots are used and the functions they serve in local communities. The purposes of this study were to provide a new revitalization planning and design proposal for the Durant-Tuuri-Mott (DTM) target area in the shrinking city of Flint, MI, USA, and to assess the final planning and design guideline through an analysis of vacant land redevelopment alternatives. Methods: For developing a revitalization planning and design guideline, this study developed several design modules with three main design themes. Then, landscape performance of the final design proposals was analyzed by three development scenarios, based on implementation level: 100%, 75%, and 50%. These development scenarios were based on the local context and different implementation budgets needed to adopt the proposed design modules. To generate a comprehensive development plan by optimizing design module allocation in the study area, this research employed a system-oriented approach, analyzing the existing cultural, natural, and built environments. A community participant process was adopted to collect stakeholders' opinions on future development. Results: By utilizing landscape performance metrics to quantify the environmental, social, and economic benefits, this study developed optimized development scenarios and a master plan for the reuse and redevelopment of existing vacant lots across DTM neighborhoods and analyzed the benefits of each. Conclusion: This research offers a flexible design method for balancing objectives in vacant land redevelopment that can be applied in other shrinking cities.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.347-354
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• 2013

In the recent global construction environment, EPC contracts that integrate planning, design, procurement, and construction have been widely used for industrial facilities. Similarly, as the importance of the engineering capability such as project management consulting(PMC) and front end engineering design(FEED) has been increased, design-build contracts also have been gradually adopted for infrastructure projects. Whereas, the Korean infrastructure industry has fragmentary features which mainly emphasize on the construction sector. Therefore, this study aims at developing strategies for enhancing the engineering capability and for balancing the competitiveness between engineering and construction sectors in the Korean infrastructure industry. To this end, the authors first carried out market analysis for both global and domestic market. Then, a structured survey and expert in-depth interviews were sequentially performed in order to reflect practitioners' perspectives and needs for institutional strategies. As a result, five strategies drawn from this study are as follows: 1) rearranging the government's roles for supporting the engineering sector; 2) establishing institutional bases being compatible with global standards; 3) fostering value-added workforce for undertaking complex tasks; 4) constructing an consortium between an engineering association and general contractors; and 5) building a nationwide collaborative networks for overseas market expansion.

• Korean Institute of Interior Design Journal
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• v.24 no.1
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• pp.64-71
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• 2015

This study aims to disclose the dynamics of Daniel Libeskind Museums by the principles of counterbalance. Balance as a dynamic concept is the settlement of instability and tension and to draw overall sense of balance by controlling new perception elements that may cope with the unbalance elements. This is based on balancing compensation and can be explained as a counterbalance. Daniel Libeskind, a representative architect of deconstructivism, creates dynamic space by using oblique lines on the plane. The study was carried out under the assumption that this space would be designed under the certain principles rather than the result of momentary feelings and the analysis was conducted by the counterpoint of music and counterbalance. As a result, Daniel Libeskind balances in a way of forming the mutual right angle by using oblique lines which cancel out the unbalance in plane composition or making the same angle based on vertical / horizontal axis. Counterbalance has been achieved in the section and elevation as well as plane and complex and diverse oblique lines were worked under the constant principle not accidental results. The axes of Daniel Libeskind's architecture have been known to follow contextualism with symbolism and historicity but it was found that a design technique considering counterbalance was used in the overall control.

• Journal of Biosystems Engineering
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• v.35 no.5
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• pp.302-309
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• 2010

Aerial application using an unmanned agricultural helicopter would allow precise and timely spraying. The attitude of a helicopter depends on a number of dynamic variables for roll-balanced flight. Laterally tilting behavior of a helicopter is a physically intrinsic phenomenon while hovering and forwarding. In order to balance the fuselage, the rotor should be counter-tilted, resulting in the biased down-wash. The biased spraying toward right side causes uneven spray pattern. In this study, a raised tail rotor system for the roll-balanced helicopter was studied. Thrust of the tail rotor system was measured and theoretically estimated for the fundamental database of the roll-balanced helicopter design. The estimated tail thrust and roll-moment would be used to design the raising height of tail rotor and roll balancing dynamics. The unmanned agricultural helicopter required the tail rotor thrust of about 39.2 N (4.0 kgf) during hovering with a payload of 235.4 N (24 kgf). A raised tail rotor system would compensate for the physical tilt phenomena. A further attitude control system of helicopter would assist roll-balanced aerial spray application.

• Korean Journal of Computational Design and Engineering
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• v.16 no.5
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• pp.315-322
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• 2011

The goal of total knee replacement (TKR) surgery is to replace patient's knee joint with artificial implants in order to restore normal knee joint functions. Since mismatched knee implants often cause a critical balancing problem and short durability, designing a well-fitted implant to a patient's knee joint is essential to improve surgical outcomes. We developed a software system that three-dimensionally (3D) simulates TKR surgery based upon 3D knee models reconstructed from computed tomography (CT) imaging. The main task of the system was to extract precise 3D anatomical parameters of a patient's knee that were directly used to determine a custom fit implant and to virtually perform TKR surgery. The virtual surgery was simulated by amputating a 3D knee model and positioning the determined implant components on the amputated knee. The test result shows that it is applicable to derive surgical parameters, determine individualized implant components, rehearse the whole surgical procedure, and train medical staff or students for actual TKR surgery. The feasibility and verification of the proposed system is described with examples.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.135-138
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• 2006

We developed an engine system design program by balancing the pressure-mass-power relation which can be acquired from each component's specification. In gas generator type open-cycle rocket engine system it is possible to distinguish the variables into two categories, which are input variables and requirement variables. We define 11 design variables corresponding to the 11 balance equations as functions of pressure, mass and power of target engine system. We solved these equations by Newton method. As an example we designed gas generator cycle engine system and finally we could conclude that this developed program is well suited to the engine system design.