• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.2
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• pp.59-67
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• 2006

The aim of this study is to evaluate the design table for envelope curve analysis of base isolated buildings, which represent the period of base isolated buildings and the lateral displacement of base isolation devices. For the construction of design table, $V_E$ spectrum, which represents the energy, is developed instead of acceleration of seismic hazard. Based on the seismic coefficient of UBC 97, boundary period $T_G$ and maximum velocity response $V_0$ are proposed considering Korea seismic hazard. Using $T_G$ and $V_0$, finally, $V_E$ spectrum is developed for the four types of soil conditions. Base on the $V_E$ spectrum, design table for envelope curve analysis is also developed for soil types.

• Journal of Oriental Neuropsychiatry
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• v.12 no.2
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• pp.103-122
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• 2001

The clinical study was carried out the 58 patients with Headache who were treated in Department of Neuropsychiatry, College of Oriental Medicine, Dae Jeon University from 14 October 1999 to 15 October 2001. The results were summarized as follows. 1. The ratio of male and female was 15:43, 40s(36.2%) was frequent, the ratio of Tension headache and Migraine was 43:12, hypernoia and overwork oneself were the most inducing factor. 2. In distribution of the period of the clinical history, Tension headache was comparatively short term within 1 month(62.8%) and Migraine was comparatively long term over 1 year(91.7%), Tension headache was frequent at whole portion(41.3%) and occipital portion(26.1%), Migraine was frequent at temporal portion(76.9%). 3. In pain type, Tension headache has many vandlike discomport type, Migraine has many pulsatile type, neck-stiffness-pain and dizziness were mainly coexited. 4. Toung aspect has many SULDAMHONGTAEBAEKHOO(舌淡紅苔白厚), GINMAEK(緊脈) and HEUNMAEK(弦脈) were frequent in Pulse type, the GAEDAMSUNKIJEETONG(祛淡順氣止痛) prescription drugs were frequent such as GEYNTONGA(肩痛A), GEYNTONGDODAMTANG(?通導淡湯), Tension headache patients were well treated(90.7%). 5. In Tension headache and Migraine, the Curve has many SL except Tension headache‘s 2th SANGHAN(상한), in Regulation RR was frequent at 1th, 2th, 3th, 4th, 7th SANGHAN and RL was frequent at 5th, 6th SANGHAN, the result of Graph, Activity and Reactivity have many low response at the whole. 6. The Curve was within normal limit at whole portion and frequent SL at temporal portion, the whole and temporal portion s Regulation also have many RR at 1th, 2th, 3th, 4th, 7th SANGHAN and RL at 5th, 6th SANGHAN, Activity and Reactivity have many low response at the whole. 7. The occipital and frontal portion‘s Curve have many SL at 1th SANGHAN, the occipital portion’s Regulation has many RR at 1th, 2th, 4th, 7th SANGHAN and RL at 5th, 6th SANGHAN, Activity has many low response at the whole, Reactivity has many low response at 1th, 4th, 5th, 6th SANGHAN and high response 2th, 3th SANGHAN, the frontal portion s Regulation has many RL at 1th, 3th, 5th, 6th, 7th SANGHAN and RR at 4th SANGHAN, Activity and Reactivity also have many low response at the whole except 6th, 7th SANGHAN respectively.

• Earthquakes and Structures
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• v.26 no.3
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• pp.239-249
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• 2024

A new layered shear continuum model box was developed to address the dynamic response issues of buried oil and gas pipelines under multi-point excitation. Vibration table tests were conducted to investigate the seismic response of buried pipelines and the surrounding soil under longitudinal multi-point excitation. A nonlinear model of the pipeline-soil interaction was established using ABAQUS finite element software for simulation and analysis. The seismic response characteristics of the pipeline and soil under longitudinal multi-point excitation were clarified through vibration table tests and simulation. The results showed good consistency between the simulation and tests. The acceleration of the soil and pipeline exhibited amplification effects at loading levels of 0.1 g and 0.2 g, which significantly reduced at loading levels of 0.4 g and 0.62 g. The peak acceleration increased with increasing loading levels, and the peak frequency was in the low-frequency range of 0 Hz to 10 Hz. The amplitude in the frequency range of 10 Hz to 50 Hz showed a significant decreasing trend. The displacement peak curve of the soil increased with the loading level, and the nonlinearity of the soil resulted in a slower growth rate of displacement. The strain curve of the pipeline exhibited a parabolic shape, with the strain in the middle of the pipeline about 3 to 3.5 times larger than that on both sides. This study provides an effective theoretical basis and test basis for improving the seismic resistance of buried oil and gas pipelines.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.631-638
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• 2006

This paper considers the nonlinear direct spectrum method to estimate seismic performance of mixed building structures without iterative computations, given dynamic property $T_1$ from stiffness skeleton curve and nonlinear pseudo acceleration $A_{1y}$ and/or ductility ratio $\mu$ from response spectrum. Nonlinear response history analysis has been performed and analysed with various earthquakes for evaluation of correctness and confidence of nonlinear direct spectrum method.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.10a
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• pp.523-528
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• 2001

The Capacity Spectrum Method (CSM) was first introduced in the 1970's as rapid evaluation procedure. The procedure compares the capacity of the structure (in the form of a pushover curve) with the demands on the structure (in the form of a response spectrum). The graphical intersection of the two curves approximates the response of the structure. In order to account for nonlinear inelastic behavior of the structural system, effective ductility ratios(μ) are applied to the elastic-linear response spectrum to imitate an inelastic response spectrum. CSM in ATC-40 has deficiencies such as performance point does not converge and the peak deformation of inelastic systems is to be inaccurate when compared against results of nonlinear response history analysis. The purpose of this paper is to investigate the variation of performance points of Capacity Spectrum Method (CSM) are investigated with respect to the different sets of earthquake ground motions. The earthquake sets were used in this study selected by Miranda(1993), Riddell(1991), Seed et al. (1976).

• Journal of Auto-vehicle Safety Association
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• v.15 no.3
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• pp.17-26
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• 2023

This paper presents extended state feedback control based on impulse response for lane change of autonomous driving vehicle. The triple characteristic root of path tracking system and longitudinal velocity determine feedback gains. We suggest a resemblance of impulse response curve of the system and lane change trajectory of the vehicle. The root affects the duration of lane change and lateral acceleration. The effect of limited lateral acceleration and saturation of steering angle will be analyzed and discussed. Finally, simulation results will show the trajectory of lane change based on impulse response under limitation of lateral acceleration.

• Journal of Environmental Policy
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• v.10 no.4
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• pp.3-37
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• 2011

This paper investigates the existence of the environmental Kuznets curve (EKC) for carbon dioxide $CO_2$ emissions and its causal relationships with economic growth and openness by using time series data (1971-2006) from China (an emerging market), Korea (a newly industrialized country), and Japan (a developed country). The sample countries span a whole range of development stages from industrialized to newly industrialized and emerging market economies. The environmental consequences according to openness and economic growth do not show uniform results across the countries. Depending on the national characteristics, the estimated EKC show different temporal patterns. China shows an N-shaped curve while Japan has a U-shaped curve. Such dissimilarities are also found in the relationship between $CO_2$ emissions and openness. In the case of Korea, and Japan it represents an inverted U-shaped curve while China shows a U-shaped curve. We also analyze the dynamic relationships between the variables by adopting a vector auto regression or vector error correction model. These models through the impulse response functions allow for analysis of the causal variable's influence on the dynamic response of emission variables, and it adopts a variance decomposition to explain the magnitude of the forecast error variance determined by the shocks to each of the causal variables over time. Results show evidence of large heterogeneity among the countries and variables impacts.

• Journal of Sensor Science and Technology
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• v.25 no.4
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• pp.243-246
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• 2016

The characteristics of a bimetallic surface plasmon resonance (SPR) chip were investigated to detect a tumor biomarker, carcinoembryonic antigen (CEA). The linewidth and the tangential slope of the reflectance curve of the bimetallic SPR chip was compared with those of the reflectance curve of a conventional gold (Au) SPR chip. The changes in reflectance in response to the variation in CEA in the critical concentration range were analyzed at an angle where the tangential slope of the reflectance curve was maximum. From linear regression analysis, the sensitivity of the bimetallic SPR chip with respect to the CEA in critical concentration was obtained.

• Smart Structures and Systems
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• v.4 no.3
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• pp.279-290
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• 2008

The modeling and parameter estimation of a damped one-degree-of-freedom mass-spring system is examined. This paper presents a method for estimating the system parameters (damping coefficients and natural frequency) from measured free-vibration motion of a system that is modeled to include both subcritical viscous damping and kinetic Coulomb friction. The method applies a commercially available least-squares curve-fitting software function to fit the known solution of the equations of motion to the measured response. The method was tested through numerical simulation, and it was applied to experimental data collected from a laboratory mass-spring apparatus. The mass of this apparatus translates on linear bearings, which are the primary source of light inherent damping. Results indicate that the curve-fitting method is effective and accurate for both perfect and noisy measurements from a lightly damped mass-spring system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.261-264
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• 1995

The response speed enhancement in picosecond photoconductor made from RF planar magnetron sputtered hydrogenated amorphous germanium thin film is discussed. Pulsed laser annealing technique was used to fabricate the highly conductive ohmic contacts and to remove the shallow deflects in the deposited photoconductive film using the different laser powers. Measured V-I curve showed -5 times bigger conductance in photoconductive gap than the one used by the conventional vacuum annealing method using strip heater.