• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.110-113
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• 2006

This paper describes the development process of body and full vehicle for reduced idle vibration through the data level of frequency and sensitivity. The vibration mode map is used to separate body structure modes from resonance of engine idle nm and steering system. This paper describes the analysis approach process to reduce the variation of uncertainties for idle vibration performance at initial design stage. The robust design method is performed to increase the stabilization performance under vehicle vibration. It is used to predict the effects of the stiffness deviation according to the spot welding condition of the body structure. The tolerance associated with hood over slam bumper is analyzed for the quality deviation of the moving system in full vehicle. And the glass sealant stiffness and weight difference is considered for the deviation characteristic. The design guideline is suggested considering sensitivity about body and full vehicle by using mother car at initial design stage. It makes possible to design the good NVH performance and save vehicles to be used in tests. These improvements can lead to shortening the time needed to develop better vehicles.

• Kyungpook Mathematical Journal
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• v.48 no.4
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• pp.665-684
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• 2008

Runge-Kutta-Nystr$\"{o}$m (RKN) methods provide a popular way to solve the initial value problem (IVP) for a system of ordinary differential equations (ODEs). Users of software are typically asked to specify a tolerance ${\delta}$, that indicates in somewhat vague sense, the level of accuracy required. It is clearly important to understand the precise effect of changing ${\delta}$, and to derive the strongest possible results about the behaviour of the global error that will not have regular behaviour unless an appropriate stepsize selection formula and standard error control policy are used. Faced with this situation sufficient conditions on an algorithm that guarantee such behaviour for the global error to be asympotatically linear in ${\delta}$ as ${\delta}{\rightarrow}0$, that were first derived by Stetter. Here we extend the analysis to cover a certain class of ODEs with low-order derivative discontinuities, and the class of ODEs with constant delays. We show that standard error control techniques will be successful if discontinuities are handled correctly and delay terms are calculated with sufficient accurate interpolants. It is perhaps surprising that several delay ODE algorithms that have been proposed do not use sufficiently accurate interpolants to guarantee asymptotic proportionality. Our theoretical results are illustrated numerically.

• The KIPS Transactions:PartA
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• v.14A no.1 s.105
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• pp.15-24
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• 2007

As a single video server exposes its limitation in scalability, capability, fault-tolerance, and cost-efficiency, solutions of this limitation emerge. However, these solutions have their own problems that will be discussed in this paper. To solve these problems and exploit various video silvers, we designed a parallel multimedia system architecture that supported a content-aware routing to heterogeneous personal computer (PC), operating system (OS), video servers through a HTTP-level redirection. We also developed a prototype, added different video servers into the prototype, and measured its overheads.

• Korean Journal of Clinical Laboratory Science
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• v.42 no.3
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• pp.125-128
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• 2010

HbA1c test measures the amount of glycated hemoglobin in blood. HbA1c shows the average of blood glucose levels for the past three months, this is a better indicator of how overall diabetes is doing. HbA1c gives a much better idea of how the body is breaking down the glucose. Therefore, this HbA1c is very important tool for maintaining normal glucose levels for pre-and diabetic patients. Total 408 participants were tested HbA1c voluntarily from Chosunilbo Health Expo (8th~11th, July 2010). Through this small-scaled direct HbA1c, about 54.7% (207 out of 408) was shown glucose tolerance and diabetes. However, 61 from 157 participants who were shown under 6.9% HbA1c (normal and pre-diabetic stage) are taking only antidiabetic drugs to maintain a normal blood glucose. Regular HbA1c test can bring an important management and awareness about controlling blood sugar level and prevention of diabetic complications.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.4
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• pp.911-925
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• 1996

Emerging service classes need an error model which efficiently satisfies the requirements for each media and application. However limited flexibility in the error control has been provided. Therefore we propose a new error control model which applies error control scheme per media flexibly with respect to ETL(Error Tolerance Leverl) and delay. In order to select the error control scheme in this model, the attributes of media(i.e., ETL, isochronism), the attributes of application(i.e., delay) and environment parameters(i.e., packet loss ration, network types, connection modes of the application) are considered as effect factors.

• Korean Journal of Pharmacognosy
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• v.52 no.4
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• pp.251-256
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• 2021

Oat, the seeds of Avena sativa L. (Gramineae), is an important dietary staple for people in many countries. Previous studies reported that A. sativa had various pharmacological effects such as anti-inflammatory, antitumor, neurotonic, and antispasmodic activities. In this study, Caenorhabditis elegans model system was used to investigate the antioxidant activity of methanol extract of oat. The ethyl acetate soluble fraction of the oat methanol extract showed the best DPPH radical scavenging activity. The ethyl acetate fraction was measured for the activity of superoxide dismutase (SOD), catalase, and oxidative stress tolerance by using C. elegans along with reactive oxygen species (ROS) level. In addition, to confirm that the regulation of the stress response gene is responsible for the increased stress tolerance of C. elegans treated by the ethyl acetate fraction, SOD-3 expression was measured using GFP-expressing transgenic worm. As a result, the ethyl acetate fraction increased SOD and catalase activities, and decreased ROS accumulation in a dose-dependent manner. In addition, the ethyl acetate fraction-treated CF1553 worm showed higher SOD-3::GFP intensity compared to the control.

• Korean Journal of Pharmacognosy
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• v.52 no.2
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• pp.105-111
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• 2021

To investigate the antioxidant activities of Pinus densiflora needle (Pinaceae), which is widely used as a traditional medicine in Korea, Caenorhabditis elegans model system was used. The n-butanol fraction of P. densiflora needle methanol extract showed the most potent DPPH radical scavenging and superoxide quenching activities in a dose-dependent manner. The n-butanol fraction was measured for the activities of superoxide dismutase (SOD), catalase, and oxidative stress tolerance by using C. elegans with reactive oxygen species (ROS) level. In addition, to see that the regulation of the stress response gene is responsible for the increased stress tolerance of C. elegans treated by the butanol extract, SOD-3 expression was measured using a transgenic strain. As a result, the P. densiflora needle n-butanol fraction increased SOD and catalase activities, and decreased ROS accumulation, dose-dependently. Furthermore, the n-butanol fraction-treated CF1553 worm showed higher SOD-3::GFP intensity than the control.

• Korean Journal of Pharmacognosy
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• v.50 no.2
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• pp.96-101
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• 2019

Methanol extract of Helianthus tuberosus L. (Compositae) flower was investigated to research the anti-oxidative activity by using a Caenorhabditis elegans model system. Ethyl acetate soluble fraction of the methanol extract showed the most potent DPPH radical scavenging activity. The ethyl acetate fraction was measured on its activities of superoxide dismutase (SOD), catalase, and oxidative stress tolerance with reactive oxygen species (ROS) level in C. elegans. Furthermore, in order to verify if regulation of stress-response gene is responsible for the increased stress tolerance of C. elegans which treated by the ethyl acetate fraction, we checked SOD-3 expression using a transgenic strain. Consequently, the ethyl acetate fraction of H. tuberosus flower increased the catalase and SOD activities in a dose-dependent manner in C. elegans, reduced ROS accumulation dose-dependently. Besides, the ethyl acetate fraction-treated CF1553 worms showed higher SOD-3::GFP intensity than the control group.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.1
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• pp.15-19
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• 2021

Objectives: The aim of this study was to evaluate correlations between anxiety and preoperative pressure pain assessments and postoperative pain and analgesic requirements in impacted lower third molar tooth surgery. Materials and Methods: This prospective study enrolled 60 patients who underwent impacted lower third molar surgery. The preoperative State-Trait Anxiety Inventory-I (STAI-I), pressure pain threshold, and pressure pain tolerance scores were measured. At 2, 4, 6, 12, and 24 hours, and at 6 days following surgery, the patients scored their pain on the visual analogue scale and recorded their analgesic drug usage. The data were evaluated, and the results were statistically analyzed. Results: Of the 60 patients, 38 were female. Mean age was 24.62±7.42 years. The study found no relationship between preoperative pressure pain assessments and postoperative pain (P>0.05). There was also no relationship observed between preoperative STAI-I scores and postoperative pain (P>0.05). However, there was a positive correlation between operation time and total medication taken (P<0.05). Conclusion: Preoperative pressure pain threshold, pressure pain tolerance, and anxiety level had no significant effects on postoperative pain and analgesic requirements in impacted lower third molar surgery.

• Korean Journal of Pharmacognosy
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• v.53 no.4
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• pp.207-212
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• 2022

Through the Caenorhabditis elegans model system, the antioxidant activity of methanol extract of Ixeis dentata was investigated. The ethyl acetate soluble fraction of the I. dentata methanol extract showed the best DPPH radical scavenging activity. The ethyl acetate fraction was measured for the activity of superoxide dismutase (SOD), catalase, and oxidative stress tolerance by using C. elegans along with reactive oxygen species (ROS) level. In addition, to confirm that the regulation of the stress response gene is responsible for the increased stress tolerance of C. elegans treated by the ethyl acetate fraction, SOD-3 expression was measured using a transgenic strain (CF1553). As a result, the ethyl acetate fraction increased SOD and catalase activity, and decreased ROS accumulation in a dose-dependent manner. In addition, the ethyl acetate fraction-treated CF1553 worm showed higher SOD-3::GFP intensity than the control worm.