• Proceedings of the KSR Conference
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• 2003.10c
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• pp.395-400
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• 2003

Adhesive joining technique is considered as one of hot issues in developing advanced composite structures. The designer should be familiar with important guidelines of fundamental principles and ideas underlying the design and application of adhesive joints for a correct joint design. This study deals with the following characteristics of adhesive joining techniques: (1) design parameters the affect the performance of joining, (2) fundamental principles and design methods of joining, (3) adhesive selection, (4) surface pre-treatment of the adherand, and (6) test methods. The results would be used to predict the performance of adhesive joints subjected to a thermal aging.

• Journal of The Korea Institute of Healthcare Architecture
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• v.15 no.2
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• pp.31-38
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• 2009

The purpose of this study is to research the fundamental cause of psychological stress and healing elements related to the waterscape design of contemporary architecture. As one of the solution, analysis of the psychological function of waterscape of natural elements in composition of architectural space was included. This study is focused on the form and psychological function of waterscape, and concerned with the cause of psychological stress at the same time. Also, this study includes analyzed cased with both inside and outside of contemporary architecture. The result will show that the waterscape will be useful solution for healing of fundamental cause of psychological stress with sixteen psychological healing elements through compositional elements of waterscape.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.30 no.3
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• pp.106-112
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• 2016

The high-voltage pulse generator consists of transformers of fundamental wave and harmonic waves, and shunt capacitors. The pulse has the fundamental wave and the harmonic waves that have been as a series circuit by the transformers to make high voltage pulse. This paper shows that pulse generator circuit is analyzed by using transformer equivalent circuits with the effect of load and simulated in time domain using Matlab program. The output voltage of pulse were obtained to 2.5kHz, 2.0kV. In high voltage circuit, capacitors are related to frequency band pass characteristics. Also, it is shown that the voltage of output pulse increases according to the growth of load.

• Advances in concrete construction
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• v.13 no.6
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• pp.451-459
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• 2022

In present study, the nonlocal Flügge shell model based is utilized to investigate the vibration characteristics of armchair and chiral single-walled carbon nanotubes with impact of small-scale effect subjected to two boundary supports. The wave propagation approach is employed to determine eigen frequencies for armchair and chiral tubes. The fundamental frequencies scrutinized with assorted aspect ratios by varying the bending rigidity. The raised in value of nonlocal parameter reduces the corresponding fundamental frequency. It is investigated with higher aspect ratio, the boundary conditions have a momentous influence on vibration of CNT. It is concluded that frequencies would increase by increasing of the bending rigidity. Solutions of the frequency equation have determined by writing in MATLAB coding.

• Advances in nano research
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• v.13 no.2
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• pp.135-146
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• 2022

The accurate assessment of the performance of nonuniform systems requires a thorough understanding of stability analysis. As a result, the theoretical modeling of the influence of various variables on the performance of small-scale nonuniform structures with conventional and non-conventional geometries is presented in this paper. According to the fundamental computer simulation based on mathematical and mechanical principles, the stability of the nonuniform structures is examined. Thus, a numerical procedure is used to simulate the stability and instability characteristics of the nonuniform small-scale structures via computer aid. Theoretic simulation methods provide a great deal of the design and production of small-scale structures at a low cost compared to experimental simulations. Thus, this paper provides a good presentation of the stability analysis of the nonuniform nanoscale structures with high accuracy without actual experimental.

• Journal of Biosystems Engineering
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• v.30 no.3 s.110
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• pp.185-191
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• 2005

Importance of alternative energy has been increasing due to environmental issues and lack of fossil fuels. In addition, heating cost that occupies from 30 to $40\%$ of the total production cost in the protected cultivation sector in Korea needs to be reduced for profitability and global competition. But, study on geothermal energy to solve these problems has not been activated for Korean protected cultivation. This study was conducted to develop an optimized geothermal exchange system through fundamental test of heat transfer characteristics in soil such as thermal diffusivity, changes in soil temperature during heating and cooling operations, and restorations of soil temperature after the heater was fumed off, These issues were investigated using computer simulation for different depths. The simulated characteristics were evaluated through controlled tests. Simulated characteristics of heat transfer in the soil at different depths showed a reasonable agreement with the results of the controlled tests. All of computer simulation and controlled tests, soil temperatures changed at 10cm and 20cm distance from pipe. but don't change at more than 30cm distance. It means that distances of heat transfer of the soil ranged from 20 to 30cm a day. Based on these results, the optimum spacing between adjacent heat exchange pipes and the pitch were selected as 50 and 40cm, respectively.

• Journal of the Korea Convergence Society
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• v.12 no.2
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• pp.29-34
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• 2021

In this paper, a cylindrical photonic crystal waveguide with a low-index core is first proposed. The core can be filled with air, liquid, or arbitrary dielectric materials. Exact analyses for the electromagnetic field characteristics of guided modes, by using appropriate Bessel functions and applying the boundary conditions, are performed to find out the guiding characteristics of the proposed waveguide. For verification and usage in design and manufacturing process, the computer-calculation of the waveguide transmission characteristics is also performed by applying the rigorous full-vectorial finite difference method. Providing variations of the effective area for the fundamental mode of the designed waveguide with different numbers of cladding layers, ranging from 2.6056 ㎛2 to 5.9673 ㎛2 over the operation wavelength, generally as the core refractive index n1 is higher, the mode area becomes smaller and the result leads to more optimistic effect for nonlinear device applications.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.269-278
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• 1998

The Planning characteristics of the canals linking river basins and estuary reservoirs have been reviewed in relation to the trend widening the areas of water resources planning. It has been also tried to justify the characteristics of the link canals in the history of irrigation development. It was concluded that the link canals were resulted from the most recent technology as far as irrigation systems were concerned, why these were long- and large-scale multipurpose canals ； the hydraulic heads of the link canals could be controlled easily ； and which consisted of open channels, pipelines and control reservoirs. The types and general characteristics of the canals have been reviewed, and the fundamental concept and characteristics in the planning of the canals have been described.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.1
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• pp.7-11
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• 1998

In this paper, a new synapse cell with nonvolatile SONOS semiconductor memory device is proposed and it's fundamental function electronically implemented SONOS NVSM has shown characteristics that the memory value, synaptic weights, can be increased or decreased incrementally. A novel SONOS synapse is used to read out the stored analog value. For the purpose of synapse implementation using SONOS NVSM, this work has investigated multiplying characteristics including weight updating characteristics and neuron output characteristics. It is concluded that SONOS synapse cell has good agreement for use as a synapse in artificial neural networks.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.682-686
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• 2001

A fundamental structural design consideration for a vehicle is the overall vibration characteristics in bending and torsion. Vibration characteristics of a vehicle system are mainly influenced by dynamic stiffness of the vehicle body structure and material and physical properties of the components attached to the vehicle body structure. The first step in satisfying this requirement is to obtain a satisfactory dynamic model of the vehicle structure. In this paper. modeling techniques of the vehicle components are presented and the effects of the vehicle components on the vibration characteristics of the vehicle are investigated,