• Smart Structures and Systems
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• v.13 no.6
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• pp.1015-1039
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• 2014

The widening project on Freeway No.1 in Taiwan has a total length of roughly 14 kilometers, and includes three special bridges, namely a 216 m long-span bridge crossing the original freeway, an F-bent double decked bridge in a co-constructed section, and a steel and prestressed concrete composite bridge. This study employed in-situ monitoring in conjunction with numerical modeling to establish a real-time monitoring system for the three bridges. In order to determine the initial static and dynamic behavior of the real bridges, forced vibration experiments, in-situ static load experiments, and dynamic load experiments were first carried out on the newly-constructed bridges before they went into use. Structural models of the bridges were then established using the finite element method, and in-situ vehicle load weight, arrangement, and speed were taken into consideration when performing comparisons employing data obtained from experimental measurements. The results showed consistency between the analytical simulations and experimental data. After determining a bridge's initial state, the proposed in-situ monitoring system, which is employed in conjunction with the established finite element model, can be utilized to assess the safety of a bridge's members, providing useful reference information to bridge management agencies.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.444-448
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• 2005

This paper presents a developing procedure of the CAN-based real-time simulator for car body control, aiming at replacing the actual W/H (Wiring Harness) and J/B(Junction Box) couple eventually. The CAN protocol, as one kind of field-bus communication, defines the lowest 2 layers of the ISO/OSI standard, namely, the physical layer(PL) and the data link layer(DLL), for which the CSMA/NBA protocol is generally adopted. For CPU, two PIC18Fxx8x's are used because of their built-in integration of CAN controller, large internal FLASH memory (48K or 64K), and their costs. To control J/B's and actuators, 2 controller boards are separately implemented, between which CAN lines communicate through CAN transceivers MCP255. A power motor for washing windshield, 1 door lock motor, and 6 blink lamps are chosen for actuators of the simulator for the first stage. For the software architecture, a polling method is used for the fast global response time despite its slow individual response time. To improve the individual response time and to escape from some eventual trapped-function loops, High/Low ports of the CPU are simply used, which increases the stability of the actuator modules. The experimental test shows generally satisfactory results in normal transmitting / receiving function and message trace function. This simulator based on CAN shows a promising usefulness of lighter, more reliable and intelligent distributed body control approach than the conventional W/H and J/B couple. Another advantage of this approach lies in the distributed control itself, which gives better performance in hard real-time computing than centralized one, and in the ability of integrating different modules through CAN.

• Journal of Agricultural Extension & Community Development
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• v.27 no.3
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• pp.111-124
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• 2020

This study begins with an interest in community capacity, the basis for mobilizing community action and the driving force of community development. The study aims to identify the structural equation model of community capacity, social participation, satisfaction in life, and the impact relationship and to verify the differences between urban and rural areas. The analysis data used the 2018Korean Social Integration Survey, which is the statistical data for national approval. The analysis method was performed by using SPSS was used to perform descriptive analysis and t-test, and the structural equation model. Multi-group analysis of AMOS was also performed to verify the research model. As the result of analysis, both the condition and status of community capacity and social participation, which are products of community capacity, showed a higher average of rural areas than urban areas. As a result of the analysis of the structural equation model between community capacity, social participation, and life satisfaction, differences between rural and urban groups were identified. In rural areas, both the capacity-condition and the capacity-status variables act as positive factors for social participation and life satisfaction, but in urban areas, the path of capacity-condition, social participation, capacity-status and life satisfaction was significant. On the other hand, social participation variables acted as a factor of direct and indirect negatively influence on life satisfaction. Therefore, it can be said that the quality of community capacity in rural areas is superior to that of urban areas.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.1
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• pp.96-113
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• 2005

The goal of this study is to build the environmental and geographic information system according to the administrative territory in Gyeongbuk province in order to resolve the mismatch between the environment attribute information and geographic information system. In order to do that, this study reviews the characteristics of local geographic information system and environmental attribute information. After that, this paper tries to figure out the way of integration between geographic and environmental informations using the administrative unit code. The result of this study can provide the basic database for building the environmental policy and improve the reality of policy analysis because this method can provide the environmental attribute database with the administrative territory information. And it will contribute to improve the environmental management system and to build the other attribute databases for the local government.

• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.2
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• pp.87-94
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• 1998

Behavioral characteristics of shallow circular arches with dynamic loading and different end conditions are analysed. Geometric nonlinearity is modelled using Lagrangian description of the motion. The finite element analysis procedure is used to solve the dynamic equation of motion, and the Newmark method is adopted in the approximation of time integration. The behavior of arches is analysed using the buckling criterion and non-dimensional time, load and shape parameters which Humphreys suggested. But a new deflection-ratio formula including the effect of horizontal displacement plus vertical displacement is presented to apply for the non-symmetric buckling problems. Through the model analysis, it's confirmed that fix-ended arches have higher buckling stability than hinge-ended arches, and arches with the same shape parameter have the same deflection ratio at the same time parameter when loaded with the same parametric load.

• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.6
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• pp.65-71
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• 2008

A one-dimensional site response analysis program (KODSAP) was developed using cyclic soil behavior model by using the modified parallel IWAN model. The model is able to predict the cyclic hardening and degradation of soil through the adjustment of the internal slip stresses of its elements beyond the cyclic threshold, and satisfies Bauschinger's effect and the Masing rule in terms of its own behavior characteristics. The program (KODSAP) used the direct integration method in the time domain. The elasticity of the base rock was considered as a viscous damper boundary condition. The effects of cyclic hardening or degradation of soil on site response analysis were evaluated through parametric studies. Three types of analyses were performed to compare the effect of analysis and cyclic parameter on site response. The first type was equivalent linear analysis, the second was nonlinear analysis, and a third was nonlinear analysis using the cyclic hardening or degradation model.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.2
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• pp.114-123
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• 2014

Vehicle Black Box (Event Data Recorder EDR) only recognizes the general surrounding environments of load. In addition, general EDR is difficult to recognize the images of a sudden illumination change. It appears that the lens is being a severe distortion. Therefore, general EDR does not provide the clues of the circumstances of the accident. To solve this problem, we estimate the value of Normalized Luminance Descriptor(NLD) and Normalized Contrast Descriptor(NCD). Illumination change is corrected using Normalized Image Quality(NIQ). Second, we are corrected lens distortion using model of Field Of View(FOV) based on designed method of fisheye lens. As a result, we propose integration algorithm of two methods that correct distortions of images using each Gamma Correction and Lens Correction in parallel.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.2
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• pp.139-145
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• 2014

Control of threshold voltage ($V_T$) by ground-plane (GP) technique for planar tunnel field-effect transistor (TFET) is studied for the first time using TCAD simulation method. Although GP technique appears to be similarly useful for the TFET as for the metal-oxide-semiconductor field-effect transistor (MOSFET), some unique behaviors such as the small controllability under weak ground doping and dependence on the dopant polarity are also observed. For $V_T$-modulation larger than 100 mV, heavy ground doping over $1{\times}10^{20}cm^{-3}$ or back biasing scheme is preferred in case of TFETs. Polarity dependence is explained with a mechanism similar to the punch-through of MOSFETs. In spite of some minor differences, this result shows that both MOSFETs and TFETs can share common $V_T$-control scheme when these devices are co-integrated.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.5
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• pp.531-542
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• 2011

The time-dependent temperature distribution across the section in bridges is determined on the basis of the three-dimensional finite element analyses and numerical time integration in this study. The material properties which change with time and thermal stress of concrete are taken into account to effectively trace the early-age structural responses. Since the temperature distribution is nonlinear and depends upon many material constants such as the thermal conductivity, specific heat, hydration heat of concrete, heat transfer coefficients and solar radiation, three representative influencing factors of the construction season, wind velocity and bridge pavement are considered at the parametric studies. The validity of the introduced numerical model is established by comparing the analytical predictions with results from previous analytical studies. On the basis of parametric studies for four different bridge sections, it is found that the creep deformation in concrete bridges must be considered to reach more reasonable design results and the temperature distribution proposed in the Korean bridge design specification need to be improved.

• Journal of Science and Technology Studies
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• v.5 no.1 s.9
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• pp.31-53
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• 2005

This paper argues that globalization of science can be put forward only through successful institutionalization of science at the national level and that the strengthened local research activities will contribute to a better integration into the global research community. In order to examine hypotheses derived from the theoretical arguments, this paper analyzes the development of physical science in Korea using mainly bibliometric method. The results show that the physical science in Korea has developed local characteristics represented by different research activities across sub-fields of physics. International research collaboration of the Korean physicists has not increased substantially during the time period studied, but an additional analysis indicates that the mode of international research collaboration may have been changed towards rather 'symmetric' way, resulting in the strengthened networks of the Korean physicists with international research community.