• Journal of Electrical Engineering and Technology
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• 제2권2호
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• pp.178-187
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• 2007

One important issue in power systems is dynamic instability due to loosing balance relation between electrical generation and a varying load demand that justifies the necessity of stabilization. Moreover, Power System Stabilizer (PSS) must have capability of producing appropriate stabilizing signals over a wide range of operating conditions and disturbances. To overcome these drawbacks, this paper proposes a new method for robust design of PSS by using an auto-tuning fuzzy control in combination with Real-Coded Genetic Algorithm (RCGA). This method includes two fuzzy controllers; internal fuzzy controller and supervisor fuzzy controller. The supervisor controller tunes the internal one by on-line applying of nonlinear scaling factors to inputs and outputs. The RCGA-based method is used for off-line training of this supervisor controller. The proposed PSS is tested in three operational conditions; nominal load, heavy load, and in the case of fault occurrence in transmission line. The simulation results are provided to compare the proposed PSS with conventional fuzzy PSS and conventional PSS. By evaluating the simulation results, it is shown that the performance and robustness of proposed PSS in different operating conditions is more acceptable

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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• pp.823-825
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• 2003

A sensor system was designed to measure real time vibro displacement of civil structure. The He-Ne laser is used for the displacement measuring method, because it guarantees short time stabilization, long time output power stability. Also, it guarantees simple maintenances and repairs under actual using condition. The line CCD image sensor(Tcd-142d) is used to detect the displacement of Ne-Ne laser responding to the vibro of civil structure. For accurate measurement and comparison, CDP-50 is used. Usually CDF-50 (Strain type displacement device) is used for the standard correction device of optical measurement equipments. The data processing part is consists of Optical sensor part, Wireless data transmission device, DAQp-1200, and LapView program. The displacement data of vibro from optical sensor part inputted to wireless data transmission device and then transmitted to DAQp-1200 in main control room. DAQp-1200 performs A/D conversion for the receiving data. After that the converted data inputted to computer system using LapView program for user display. The significance of this paper is to develope a convenient, accurate and lost saving real time displacement measurement system for the civil structure.

• 한국정밀공학회지
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• 제33권12호
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• pp.1031-1037
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• 2016

This study was to verify the effect of complex training programs on the postural balance and trunk muscle strength of the elderly. We recruited 40 elderly participants aged 60 to 75 years. Subjects were evaluated before, and 12 weeks after. The participants underwent complex training programs, including free exercise, elastic band and unstable plate. Exercise were performed as follows: 10 repeats in 50 minutes (0 to 4 weeks), 13 repeats in 50 minutes (5 to 8 weeks), and 15 repeats in 50 minutes (9 to 12 weeks). The training group underwent complex training, including warm up, thrice a week for twelve weeks. The control group did not perform any complex training. Results indicate that the postural balance and trunk muscle strength in the training group significantly increased. Data generated from this study could be applied to develop a complex training program to efficiently build whole body muscle strength.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.786-789
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• 2005

The proper parameters in a twin roll strip casting are important to obtain the stabilization of the Mg sheet. What is examined in this paper is the quantitative relationships of the important control parameters such as the roll speed, height of pool region, outlet size of nozzle, solidification profile and the final point of solidification in a twin roll strip casting Unsteady conservation equations were used for transport phenomena in the pool region of a twin roll strip casting in order to predict a velocity, temperature distributions of fields and a solidification process of molten magnesium. The energy equation of cooling roll Is solved simultaneously with the conservation equations of molten magnesium In order to consider the heat transfer through the cooling roil. The finite difference method (2-D) and the finite element method (2-D) are used in the analysis of pool region and cooling roil to reduce computing time and to improve the accuracy of calculation respectively.

• 대한물리의학회지
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• 제7권3호
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• pp.275-282
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• 2012

Purpose : Bridge exercise has been commonly used in clinical rehabilitation settings to improve trunk control, and hip adductor muscles were a related muscle that may affect trunk muscle activation. The aim of this study was to investigate whether the co-contraction of hip adductor muscles may affect trunk muscle activation during bridge exercises. Methods : Thirty-eight healthy young subjects (19 men and 19 women) performed bridge exercises (with and without hip adduction movement). Surface electromyography (EMG) data were collected from the dominant-side internal oblique (IO), rectus abdominis (RA), multifidus (MF) and erect spine (ES) during bridge exercises to compare trunk muscles activation patterns. Result : The EMG activities of IO and RA appeared to be significantly higher during bridge exercise with hip adductor co-contraction than during bridge exercise alone (p<.01), but there were no significant differences in those of MF and ES. Furthermore, there were significant differences in the IO:RA EMG ratio during bridge exercise with hip adductor co-contraction (p<.05). Conclusion : These findings suggest that integration of hip adduction during bridge exercise may be beneficial in increasing deep muscles' activity for trunk stabilization.

• 한국지능시스템학회논문지
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• 제16권6호
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• pp.753-758
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• 2006

본 논문에서는 하이브리드 발전 시스템에서의 최대 전력 추종을 위한 디지털 퍼지 제어기 설계를 목표로 한다. 하이브리드 발전 시스템은 풍력과 태양광, 두 개의 발전 시스템으로 구성된다. 각 발전기에서 전압과 전류는 일반적으로 비선형 관계에 있기 때문에, 퍼지 모델 기반 제어기를 사용하여 비선형성을 효율적으로 제어하게 된다. 또한 마이크로프로세서 기반제어 시스템의 구축을 위하여 최신 디지털 재설계 기법을 사용하며, 디지털 퍼지 제어기를 설계하게 된다. 마지막으로 하이브리드 발전 시스템의 플랜트를 통한 실험으로써 본 제안 기법의 우수성을 입증한다.

• 대한상한금궤의학회지
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• 제10권1호
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• pp.125-132
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• 2018

Objective : The purpose of this study is to review a case of hypertension. The patient was 41 years, a male. We stabilized blood pressure after administration of Daehuanghuanglianxiexin-tang. In this paper, we review the interpretation of Shanghanlun by analyzing the patient's progress, diagnosis, treatment. Methods : Blood pressure changes have been monitored during the period. Additionally, We have observed the patients' compliance and accompanied symptom by the timeline analysis. Results : According to Shanghanlun disease pattern identification diagnostic system, Wediagnosed a Greater yang disease. The patient was treated with Daehuanghuanglianxiexin-tang for 2 months. Daehuanghuanglianxiexin-tang was able to control blood pressure to under 120mmhg / 80mmhg. During the treatment period, the accompanied symptom Stiffness and pain in posterior neck has improved, patient's compliance was good, and symptoms improved without significant complication Conclusions : Taking of the Daehuanghuanglianxiexin-tang makes patient's blood pressure controlled to safe and stable range and eases the discomfort of posterior neck pain.

• 한국공간구조학회논문집
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• 제19권1호
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• pp.45-51
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• 2019

In this study, the static load test and the load transfer test were carried out to evaluate the structural performance of the circular anchorage proposed by the previous study. Specimens were fabricated according to KCI-PS101 and ETAG 013. As a result of the static load test, it was verified that the displacement of the wedge and the strand was kept constant when the tensile force of 80% of the nominal strength of the strand was applied. In the load transfer test, it was confirmed that all the specimens satisfied the stabilization formula of KCI-PS101 and ETAG 013. Post-tensioned one-way slab with circular anchorage were fabricated to evaluate the flexural behavior. All specimens exhibited the same flexural behavior and maximum load. However, the specimen with circular anchorage were advantageous than the rectangular anchorage one in terms of crack control of the anchorage zone.

• Archives of Pharmacal Research
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• 제23권4호
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• pp.267-282
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• 2000

Cytochrome P45O (CYP) 2E1 catalyzes the metabolism of a wide variety of therapeutic agents, procarcinogens, and low molecular weight solvents. CYP2E1-catalyzed metabolism may cause toxicity or DNA damage through the production of toxic metabolites, oxygen radicals, and lipid peroxidation. CYP2E1 also plays a role in the metabolism of endogenous compounds including fatty acids and ketone bodies. The regulation of CYP2E1 expression is complex, and involves transcriptional, post-transcriptional, translational, and post-translational mechanisms. CYP2E1 is transcriptionally activated in the first few hours after birth. Xenobiotic inducers elevate CYP2E1 protein levels through both increased translational efficiency and stabilization of the protein from degradation, which appears to occur primarily through ubiquitination and proteasomal degradation. CYP2E1 mRNA and protein levels are altered in response to pathophysiologic conditions by hormones including insulin, glucagon, growth hormone, and leptin, and growth factors including epidermal growth factor and hepatocyte growth factor, providing evidence that CYP2E1 expression is under tight homeostatic control.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제4권3호
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• pp.95-103
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• 2023

This study aimed to identify the initial migratory macroinvertebrate species in two newly created mountain wetlands. To analyze the initial immigration species of macroinvertebrates, two experimental sites and two control sites were selected after habitat creation and investigated thrice from spring to fall. Benthic macroinvertebrates were collected quantitatively from each site using a Surber sampler and Modified D-frame deep net. After restoration at the two experimental sites, the number of macroinvertebrate species and individuals gradually increased from spring to fall and continued to increase over time with the development of waterside vegetation and habitat stabilization at the experimental sites. The species initially introduced to mountain wetlands after their creation were Ephemera strigata, Ephemera orientalis, Chironomidae sp., and Aquaris paludum. Subsequently, predators such as Davidius lunatus, Sieboldius albardae, Oyamia nigribasis, and Sialis longidens were introduced. Additionally, as a differentiating physicochemical factor between the two habitats, current velocity, which determines the distribution characteristics of benthic macroinvertebrates, and water temperature, which impacts the growth of organisms, showed a relatively stronger influence.