• Journal of Korean Neurosurgical Society
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• v.29 no.6
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• pp.822-825
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• 2000

Lymphocytic infundibuloneurohypophysitis is a rare inflammatory disorder, which may be caused by autoimmune response, affecting the infundibulum and the posterior lobe of the pituitary gland. The authors present a 15-year-old man with central diabetes insipidus, whose sellar magnetic resonance imaging (MRI) showed a focal thickening of the infundibulum and loss of high signal of the normal neurohypophysis on T1-weighted images. The histopathological diagnosis was lymphocytic infundibuloneurohypophysitis. When a patient presents with central diabetes insipidus and infundibular thickening on brain MRI, this entity should be included in the differential diagnosis though it is very rare. The significance of this entity in treatment is that it is basically not a surgical one, and surgery is needed only for tissue diagnosis. Symptomatic treatment and observation make it regress spontaneously.

• Journal of the Korean Society of Hazard Mitigation
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• v.4 no.1 s.12
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• pp.1-14
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• 2004

The objective of this study is firstly to frame up the seismic safety of concrete gravity dams. It is necessary to analyze seismic response and evaluate seismic performance of concrete gravity dams during earthquake. In this study, seismic damage and dynamic analysis of concrete gravity dams using structural analysis package such as SAP2000 and MIDAS were performed. Additional dynamic water pressure due to earthquake considered as additional mass for numerical seismic analysis. According detailed analysis, the vibration through the dam structure (transverse to water flow) seems to be very critical depending on the shape of the dam. For more precise evaluation of seismic fragility of concrete gravity dams, further research is still needed.

• Journal of Astronomy and Space Sciences
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• v.34 no.2
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• pp.119-125
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• 2017

We retrieved rotational temperatures from emission lines of the OH airglow (8-3) band in the sky spectra of the Sloan digital sky survey (SDSS) for the period 2000-2014, as part of the astronomical observation project conducted at the Apache Point observatory ($32^{\circ}N$, $105^{\circ}W$). The SDSS temperatures show a typical seasonal variation of mesospheric temperature: low in summer and high in winter. We find that the temperatures respond to solar activity by as much as $1.2K{\pm}0.8K$ per 100 solar flux units, which is consistent with other studies in mid-latitude regions. After the seasonal variation and solar response were subtracted, the SDSS temperature is fairly constant over the 15 year period, unlike cooling trends suggested by some studies. This temperature analysis using SDSS spectra is a unique contribution to the global monitoring of climate change because the SDSS project was established for astronomical purposes and is independent from climate studies. The SDSS temperatures are also compared with mesospheric temperatures measured by the microwave limb sounder (MLS) instrument on board the Aura satellite and the differences are discussed.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.49 no.6
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• pp.334-338
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• 2000

Even though it is not practical, yet there is a trend of the researches related to the anesthesia on the determination of depth of anesthesia and level of consciousness in the view point of neurophysiological aspects. That is, quantification of physiological signals which represent human brain function and pharmacological response could be used to find the level of consciousness based on the changes in physiological signals. This research was performed to analyze the relationship between parameters extracted from LAEP(long latency auditory evoked potential) and the amount of sedatives injected to the patients. Seventeen patients were participated for the experiment. Two different sedatives, midazolam and diazepam, were injected intramuscularly, and LAEPs caused by 1KHz and 2KHz auditory tone bust were obtained. It was found that amplitude of extracted parameters from LAEP, N100 and P300, were reduced as dose of sedatives were increased. Results of this study could be used for extracting more meaningful index and establishing algorithm for predicting changes of level of consciousness induced by sedatives.

• Proceedings of the KIEE Conference
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• 2000.11d
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• pp.650-652
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• 2000

Although Fuzzy Logic Controller(FLC) adopted three terms as input gives better performance. FLC is in general composed of two-term control because of the difficulty in the construction of fuzzy rule base. In this paper, a three-term FLC which is similar to PID control but acts as a nonlinear controller is proposed. To reduce the complexity of the rule base design and increase efficiency, a simplified fuzzy PID control is induced from a hybrid velocity/position type PID algorithm by sharing a common rule base for both fuzzy Pi and fuzzy PD parts. It is simple in structure, easy in implementation, and fast in calculation. The phase plane technique is applied to obtain the rule base for fuzzy two-term control and them. The resultant rule base is Macvicar-Whelan type. The frequency response information is used in tuning of membership functions. Also a tuning strategy for the scaling factors is Proposed based on the relationship between PID gain and them. Simulation results show better performance and the effectiveness of the proposed method.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.37-39
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• 2000

This paper describes the application of Fuzzy Logic Controller (FLC) to Thyristor Controlled Series Capacitor (TCSC) which can have significant impact on Power system dynamics. The function of the FLC is to control the firing angle of the TCSC. We tuned the scaling factors of the FLC using Tabu Search. The proposed FLC is used for damping the low frequency oscillations caused by disturbances such as the sudden changes of small of large loads or the outages in the generators or transmission lines. To evaluate usefulness of the proposed FLC. we performed the computer simulation for single-machine infinite system. The response of FLC is compared with that of PD controller optimized using Tabu Search. Simulation results that the FLC shows the better control performance than PD controller.

• Journal of Korean Society of Steel Construction
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• v.12 no.1 s.44
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• pp.83-91
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• 2000

The first Procedure to identify structural system by using measured data is transformation of data to frequency domain and try to recognize modal characteristics in graphical condition. Those methods are doubted about the reliability to the civil structures, especially bridges which has coupled and close modal characteristics. In this paper, feasibility of time domain modal Identification methods were examined and applied double least square method to overcome bias characteristics of the identification methods. To show the advantage of proposed method, simulation were carried out for mass-spring model. And to examine the usage of the method in realistic case, sensitivity of the methods to noise was performed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.57
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• pp.51-62
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• 2000

In this study, the psycho-physiological response of drivers was investigated in terms of EEG(Electroencephalogram), especially with the fractal dimensions computed by Chaotic algorithm. The Chaotic algorithm Is well Known to sensitively analyze the non-linear information such as brain waves. An automobile with a fully equipped data acquisition system was used to collect the data. Ten healthy subjects participated in the experiment. EEG data were collected while subjects were driving the car between Won-ju and Shin-gal J.C. on Young-Dong highway The results were presented in terms of 3-Dimensional attractor to confirm the chaotic nature of the EEG data. The correlation dimension and fractal dimension were calculated to evaluate the complexity of the brain activity as the driving duration changes. In particular, the fractal dimension indicated a difference between the driving condition and non-driving condition while other spectral variables showed inconsistent results. Based upon the fractal dimension, drivers processed the most information at the beginning of the highway driving and the amount of brain activity gradually decreased and stabilized. No particular decrease of brain activity was observed even after 100 km driving. Considering the sensitivity and consistency of the analysis by Chaotic algorithm, the fractal dimension can be a useful parameter to evaluate the psycho-physiological responses of human brain at various driving conditions.

• Fisheries and Aquatic Sciences
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• v.3 no.1
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• pp.52-63
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• 2000

Non-specific reaction has been a problem in doing, especially, research and diagnosis for infectious agents. Avidin-biotin-peroxidase complex (ABC) techniques has widely been used to amplify a reaction. Photobacterium damse1a subsp. piscicdia (formerly Pasteurella piscicida) exhibited a capacity to bind with streptavidin non-specifically. The band, estimated 26 K Da in Western blotted paper, was blocked with biotin but incompletely. In an attempt to explore an involvement of the non-specific substance in attaching piscine cells, cell attachment test performed using anti- Ph. d. subsp piscicida sera raised mouse and rabbit exhibited slightly blocking effects for Mediterranean (1736) and significantly for Japanese (Sp 92144) isolate. Biotin decreased the attachment ability significantly for Sp92144 but it was not effective to 1736. Both isolates showed greatly enhanced attachment ability with poly-L-lysin. The non-specific binding substance was contained in bacterial extracellular products (ECPs). The substance was able to purified with 2-imminobiotin affinity column, the purified substance appeared to have 4 bands in silver staining, and had a carbohydrate branch. This purified substance showed cytotoxic effects selectively between 5 piscine cell lines. Moreover, it stimulated rainbow trout macrophage in terms of reduction of cytochrome cas well as yeast phagocytosis, significantly.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.2
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• pp.46-54
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• 2000

Because the installation of the optical cables in rooms is difficult, we can terminate the optical cable at the main enterence and use infrared wireless communications in the room. In this paper, we calculate the impulse response of the infrared wireless communication link and the optical power penalty due to multipath effect up to the third reflections with the source on the sidewall. We can locate the optical sources on the sidewall without problem because of relative large power reflected from the ceiling and sidewalls once. And the optical power penalty due to multipath effect can be neglected at the speed of 2 Mb/s.