• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.128-131
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• 2005

Structural Dynamics Modification (SDM) is a very effective technique to improve structure's dynamic characteristics by adding or removing auxiliary structures. changing material properties and shape of structure. Among those of SDM technique, the method to change shape of structure has been mostly relied on engineer's experience and trial-and-error process which are very time consuming. In order to develop a systematic method to change structure shape, surface grooving technique is studied and successfully applied to HDD cover model. To check the effectiveness of this surface grooving technique, the grooved HDD cover design was manufactured using rapid prototyping and experimentally tested to prove the effectiveness of the grooving method as one of SDM techniques. And the modal strain energy and eigenvalue sensitivity method for choosing the initial starting point are compared.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.1
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• pp.9-16
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• 2021

Modern combat has been extended to the concept of real-time response to a variety of threats simultaneously occurring in vast areas. In order to quick command determination and accurate engagement in these threats, the combat system has emerged in frigate. Frigates conduct anti-surface, anti-submarine, and anti-aircraft as the core forces of the fleet. In this study, the combat effectiveness measures naval frigates using AHP (analytic hierarchy process) method. A hierarchical structure for measuring the combat effectiveness was developed, and weights of criteria were calculated by expert surveys and pair-wise comparisons. In addition, the combat effectiveness of frigates was synthesized and compared. The weights for each attribute were calculated, and the weights for the three main attributes were in the order of act (0.594), evaluate (0.277), and see (0.129). As a result of calculating the weight, anti surface warfare (0.203) was the highest. The combat effectiveness of FFG Batch-III, which has advanced hardware and software and improved combat system capabilities, see (1.73 to 2.56 times), evaluate (1.68 to 2.08 times), and act (1.31 to 3.80 times) better than the comparative frigate. In summarizing the combat effects of the frigate, FFG Batch-III was 1.41~2.95 times superior to the comparative frigate. In particular, a group of experts evaluated the act importantly, resulting in better combat effectiveness.

• Journal of the Korean institute of surface engineering
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• v.48 no.4
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• pp.149-157
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• 2015

We investigated the effects of the fabric structure or the kinds of plated metals on the electromagnetic interference shielding effectiveness (EMI SE) by means of electroless plating on polyester fabric. We found that the weight of deposited metal, EMI SE, and flexibility of the conductive fabric for EMI shield is affected by morphology of fabric and structure of fiber. The EMI SE of conductive fabric plated Ni/Cu/Ni by electroless plating method on draw textured yarn (DTY) polyester was in the practically useful range of above 70 dB over a wide frequency range of 10 MHz to 1.0 GHz at the surface resistivity of $0.05{\Omega}/{\square}$. Au or Ag plated conductive fabric by immersion plating method is not able to provide for a good EMI SE.

• Herbal Formula Science
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• v.27 no.4
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• pp.285-297
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• 2019

Objectives : The purpose of this study is to analyze effectiveness of herbal medicine treatment on Dry Eye Syndrome. Methods : We analyze medical records of 114 patients who visited Indara oriental medical clinic for dry eye syndrome. Patients were treated with acupuncture and Inmok-tang, and the ocular surface disease index was evaluated before and after treatment. Results : Analysis of 114 medical records showed a significant decrease in the pre-treatment and post-treatment ocular surface disease index, and a statistically significant positive correlation between the duration of Inmok-tang administration and the change in the ocular surface disease index. Conclusions : Herbal medicine treatment with Inmok-tang reduces the Ocular Surface Disease Index, an indicator of subjective symptoms of dry eye syndrome.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.3
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• pp.1026-1039
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• 2014

We present a new method for generating sweep surfaces using bivariate B-spline motion. The sweep surface is defined as the trace of a single point under bivariate B-spline motion. Direct manipulation of the sweep surface is achieved by controlling its motion components while producing various editing effects. We demonstrate the effectiveness of our technique by modeling and deforming various three-dimensional shapes.

• Journal of the Korean Society of Safety
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• v.13 no.1
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• pp.64-69
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• 1998

Three kinds of N-fluoroacyl carboxy pyridinium chlorides were synthesized by the reaction of pyridine-carboxylic acid such as pyridine-2-carboxylic, pyridine-3-carboxylic and pyridine-4-carboxylic acid with long chain perfluoroacyl chloride. The surface chemical properties including surface tension, foaming power, foam stability, effectiveness of wettability and solubilizing effect were measured. These compounds showed good surface activities as emulsifying agent, solubilizing agent and fire-fighting agent.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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• pp.47-53
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• 2003

Screen filter of PDP TV plays an important role in satisfying the EMI/EMC specifications. Two types of filters, the mesh type and the sputter type, are used in PDP TVs, and this paper presents measurement results of the shielding effectiveness (SE) in the frequency range from 50MHz to 1GHz. Two methods were used for the measurement, one using network analyzer (NA) in an open area test site(OATS), and the other using the screen room. The overall conclusion is that the shielding effectiveness of the screen filter is related to the surface resistance of the screen filter. The mesh type screen filters are superior to the sputter types in the shielding effectiveness, which is varying with the frequency.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.7
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• pp.661-667
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• 2010

This paper presents a failure diagnosis and accommodation strategy which is capable of tolerating faulty actuators of a submersible vehicle. The proposed method is mainly based on a sliding mode control technique. The primary ideas include a performance index to describe the effectiveness of actuators, and a controller reconfiguration strategy using the actuator effectiveness index. The actuator effectiveness proposed in this work is defined as the relationship between the sliding surface and the controlled system behavior. The resulting actuator effectiveness is then used in reconfiguring the controller in order to counteract for the deteriorated control performance in the presence of a faulty actuator. The effectiveness of the proposed method is demonstrated by means of numerical simulations with a submersible vehicle.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.183-184
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• 2023

The purpose of this study is to compare and analyze the effect of type and volume fraction of fiber on the electrical conductivity and shielding effectiveness of cementitious composites. The large specific surface area of amorphous metallic fiber, as well as the high number of fibers per unit weight, provided an advantage in the formation of conductive path. As the result, the electrical conductivity of amorphous metallic fiber was evaluated to be higher, and the shielding effectiveness was also higher. However, the shielding effectiveness according to electrical conductivity was confirmed to have a threshold point, and further research is needed to improve it.

• Transactions of Materials Processing
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• v.16 no.7
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• pp.538-548
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• 2007

In this paper, a novel approach which enables rapid die surface modification for sheet metal forming process is proposed. In this method an implicit surface which interpolates a given set of control points and displacement constraints is generated to compute the displacements at arbitrary points located on die surface. The proposed method does not depend on the underlying surface representation type and is affected neither by its complexity nor by its quality. In addition, the domain decomposition method is introduced in order to treat large surface model. The global domain of interest is divided into smaller domains where the problem can be solved locally. And then the local solutions are combined together to obtain a global solution. In order to verify the validity and effectiveness of the proposed method, various surface modifications are carried out fur three kinds of die surface model including polygonal surface composed of triangular and rectangular meshes, polynomial surface and NURBS surface.