• Conservation Science in Museum
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• v.18
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• pp.51-64
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• 2017

The Bracket clock in the collection of the Korean Christian Museum at Soongsil University underwent conservation treatment for a special exhibition. The compositional analysis showed that the body was made of brass plated with gold by fire-gilding(gold amalgam process), while the dial was identified as pure copper coated with enamel. The hands were made of steel. Remnants of adhesive tape on the dial were cleaned, followed by the addition of a protective coating. In order to restore it to a condition as similar to its original form as possible, replacements for missing parts were newly constructed out of brass and were connected to the hands and the dial. The dial was then fixed to the body using an acrylic support. The compositional analysis and conservation treatment have left the clock in stable condition and readily available for exhibitions and future studies.

• Conservation Science in Museum
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• v.11
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• pp.1-8
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• 2010

Conservation re-treatment of dagger and scabbard in Gyeongju National Museum, which were excavated from Gyerim-ro Tomb No. 14 (Treasure No. 635) was carried out after a wide-scale dissembling in order for publishing a report and holding a special exhibition. The interior shape of the iron dagger which was disclosed by ornament plates was confirmed by X-ray investigation. The results of XRF analysis which was used to analyse compositions of the golden ornament plates reveal that having more than 3% of copper distinguishes it from other Silla gold artifacts. The conservation treatment progressed in a way that surface contaminants were removed and insecure areas were consolidated. The original shape of the iron dagger and scabbard was found after adhering and restoration. With the ornament plates staying on the iron dagger, a stand in acrylic for display and storage was made, which is able to place the dagger and scabbard in the safest way.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.4
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• pp.1059-1064
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• 2003

Oldenlandiae Herba has been used for the prevention or treatment of cancer in oriental medicine for years. Experimentally its antitumor activity was reported. However, in order to develop new Korean original plants. we tried to study the antitumor activity of Chinese and Korean origin Oldenlandiae Herba. We first evaluated the cytotoxicity of Oldenlandiae Herba originated from China and Korea on HT1080, U937 and SK-mel tumor cells. MeOH extract of Chinese Oldelandiae Herba was more effective than MeOH extract of Korean Oldenlandiae Herba. Approixmately IC50 of two species of Oldelandiae Herba was 380-450 ug/ml. For evaluation of antiangiogenic activity, proliferation assay with HUVECs(Human umblical vein endothelial cells) was done with three samples. Chinese Herba and Korean Herba and root. Korean root and herba was more effective than Chinese Herba. Thus, we found Korean Oldenlandiae was more effective on angigenic activity than Chiness Oldenlandiae. In an anlytical study on effective compounds from Oldenlandiae, the spot of ursolic acid was more marked by Korean Oldenlandiae than by Chinese Oldenlandiae. whereas the spot of asperuloside was more pronounced by Chinese Oldenlandiaethan by Korean Oldenlandiae by TLC analysis.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.963-966
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• 2005

Model updating method is known to the area to correct finite element models by the results of the experimental modal analysis. Most common methods in model updating depend on a parametric model of the structure. In this case, the number of parameters is normally smaller than that of modal data obtained from an experiment. In order to overcome this limitation, many researchers are trying to get modal data as many as possible to date. 1 want to name this method multiple modified-system generation method. These Methods consist of direct system modification method and feedback controller method. The direct system modification Is to add a mass or stiffness on the original structure or perturb the boundary conditions. The feedback controller method is to make the closed food system with sensor and actuator so as to get the closed loop modal data. In this paper, we need to focus on the feedback controller method because of its simplicity. Several methods related the feedback controller methods are virtual passive controller (VPC) sensitivity enhancement controller (SEC) and mode decoupling controller (MDC). Among them, we will apply MDC to the model updating problem. MDC has various advantages compared with other controllers, such as VPC and SEC. To begin with, only the target mode can be changed without changing modal property of non-target modes. In addition, it is possible to fix any modes if the number of sensors is equal to that of the system modes. Finally, the required control power to achieve desired change of target mode is always lower than those of other methods such as VPC. However, MDC can make the closed loop system unstable when using incomplete modal data. So we need to take action to avoid undesirable instability from incomplete modal data. In this paper, we address the method to design the unique and robust MDD obtained from incomplete modal data. The associated simulation will be Incorporated to demonstrate the usefulness of this method.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.4
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• pp.328-338
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• 2007

One of main advantages of composite using smart material as reinforcement can be controlled cracks behavior inside the composite. If the smart composite is applied as part of the structure, the use of the shape memory effect of the smart material is the best way to protect the propagation of cracks generated in the structure while use. In this study, the optical manufacturing conditions for the smart composite were derived. In order to evaluate the shape memory effect by shape memory alloy, the tensile load was applied to the smart composite and stress distribution was inspected. And then, the smart composite was heated to a certain temperature and the shape memory alloy would shrink to the original shape. Finally, at this point the recovering status of stress using photoelastic instrument was discussed.

• Journal of KIISE:Computer Systems and Theory
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• v.31 no.5_6
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• pp.288-296
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• 2004

This paper proposes a new mesh simplification algorithm using differential error metric. Many simplification algorithms make use of a distance error metric, but it is hard to measure an accurate geometric error for the high-curvature region even though it has a small distance error measured in distance error metric. This paper proposes a new differential error metric that results in unifying a distance metric and its first and second order differentials, which become tangent vector and curvature metric. Since discrete surfaces may be considered as piecewise linear approximation of unknown smooth surfaces, theses differentials can be estimated and we can construct new concept of differential error metric for discrete surfaces with them. For our simplification algorithm based on iterative edge collapses, this differential error metric can assign the new vertex position maintaining the geometry of an original appearance. In this paper, we clearly show that our simplified results have better quality and smaller geometry error than others.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.9
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• pp.4119-4124
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• 2011

In a MPC coding using excitation source of voiced and unvoiced, it would be a distortion of speech waveform in case of increasing or decreasing of speech signal amplitude in a frame. This is caused by normalization of synthesis speech signal in the process of restoration the multi-pulses of representation section. To solve this problem, this paper present a method of amplitude compensation(AC-MPC) in a multi-pulses each pitch interval in order to reduce distortion of speech waveform. I was confirmed that the method can be synthesized close to the original speech waveform. And I evaluate the MPC and AC-MPC using amplitude compensation method. As a result, SNRseg of AC-MPC was improved 0.7dB for female voice and 0.7dB for male voice respectively. Compared to the MPC, SNRseg of AC-MPC has been improved that I was able to control the distortion of the speech waveform finally. And so, I expect to be able to this method for cellular phone and smart phone using excitation source of low bit rate.

• Journal of Korea Multimedia Society
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• v.11 no.7
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• pp.966-976
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• 2008

Providing Quality-of-Service(QoS) guarantee requires the reservation of resource needed to accommodate the traffic flow of service for which resource reservation protocol(RSVP) was introduced. However, if any RSVP-capable router on the path fails to accommodate the traffic flow due to lack of resource, the flow is not allowed no matter how much surplus resources other routers on the path have. In order to solve this problem, this paper proposes a resource reservation method that can adjust adaptively the delay budget of traffic flow allocated to each RSVP-capable router in which the router uses the recently developed general-time fair queuing scheduler. The results of the simulation applying the proposed method to an evaluation network show that it may yield the gain of up to 90% compared to that in the original one in terms of the number of admitted flows.

• Journal of Information Management
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• v.33 no.2
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• pp.67-94
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• 2002

With the development of modern society, we are all living in a world where information is shared through mass media and environment. Just as there was an identifier for the approach of information in the past analog environment, there is a demand for the continuous development and research of an original identifier for each and every digital contents of the changing digital environment. In order to present the need for standardization of effective construction concerning digital contents, this study examines the identifiers system structure of ISBN and ISSN of the analog environment and URL, URN, URC, which are under the URI system of the digital environment. After analyzing the problems of different URL identifiers construction in each university library's OPAC system, this study presents a standard device of effective identifiers patterns.

• Journal of KIISE:Computer Systems and Theory
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• v.28 no.11
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• pp.561-572
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• 2001

Since energy consumption of CMOS circuits has a quadratic dependency on the supply voltage, lowering the supply voltage is the most effective way of reducing energy consumption. We propose an intra-task voltage scheduling algorithm for low-energy hard real-time applications. Based on a static timing analysis technique, the proposed algorithm controls the supply voltage within an individual task boundary. By fully exploiting all the slack times, as scheduled program by the proposed algorithm always complete its execution near the deadline, thus achieving a high energy reduction ratio. In order to validate the effectiveness of the proposed algorithm, we built a software tool that automatically converts a DVS-unaware program into an equivalent low-energy program. Experimental results show that the low-energy version of an MPEG-4 encoder/decoder (converted by the software tool) consumes less than 7~25% of the original program running on a fixed-voltage system with a power-down mode.