• Proceedings of the Korea Concrete Institute Conference
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• 1990.04a
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• pp.35-38
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• 1990

Depths of the vertical cracks in the concrete were determined by the time of flight of the ultrasonic waves. The ultrasonic waves are diffracted at the crack tip, and the arrival time of ultrasonic waves are dependent on the crack depth and speration distance between transmitting and receiving ultrasonic transducers. The vertical cracks with 0.2-2mm width and 10-100mm depth were examined by multi-layered ultrasonic transducers. It was found that the time of flight of ultrasonic waves were proportional to the depth of vertical cracks. The depth of vertical cracks in the range of 20-100mm depth could be determined by the transient time of the diffracted ultrasonic waves

• Journal of electromagnetic engineering and science
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• v.18 no.1
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• pp.35-40
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• 2018

This study presents a vertical-type CMOS Hall device with improved sensitivity to detect a 3D magnetic field in various types of sensors or communication devices. To improve sensitivity, trenches are implanted next to the current input terminal, so that the Hall current becomes maximum. The effect of the dimension and location of trenches on sensitivity is simulated in the COMSOL simulator. A vertical-type Hall device with a width of $16{\mu}m$ and a height of $2{\mu}m$ is optimized for maximum sensitivity. The simulation result shows that it has a 23% better result than a conventional vertical-type CMOS Hall device without a trench.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.568-569
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• 2011

As an answer for need for minimizing the road excavation of a box type tunnel, a method of vertical snake was developed, which is very economical and easy to construct. The reason why it is good is, the road excavation width, steel accessories, the road occupation space decreases with the technology. The pros and cons of 345kV XLPE $2,500mm^2$ horizontal and vertical snake are listed below. In this study, topics such as 345kV XLPE $2,500mm^2$ vertical snake construction standard and the development process of steel accessories, vertical snake construction procedure will be covered.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.1
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• pp.55-61
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• 2009

In this paper, a thrust prediction method for a developing vertical launching missile is proposed through considering a verified vertical launching missile(a baseline missile) as a model. In order to predict thrust profile of a developing vertical launching missile, both Similarity law and Pi theory are applied to the model. By comparing prediction results based on the 6-DOF program of a baseline missile with simulation results of a developing vertical launching missile, the proposed method has been indirectly verified.

• Earthquakes and Structures
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• v.14 no.5
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• pp.449-458
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• 2018

Earthquakes have shown the vulnerability of unreinforced masonry (URM) structures. The aim of this research is to study a technique for in-plane seismic retrofitting of URM walls in which both diagonal and vertical steel strips are added to a single side of a URM wall. Specimens have been tested under quasi-static cyclic lateral load in combination with constant vertical load. The tests show that vertical and diagonal strips cause a significant increase in seismic capacity in terms of both strength (about 200%) and displacement at maximum (about 20%). Furthermore, this technique caused the failure modes of URM walls were influenced.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.6
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• pp.83-90
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• 2009

This study was carried out to evaluate the vertical stress properties in sandy soil according to changes of loading type in soil bin compacted three layers. The following conclusions and comparisons have been made based on careful analysis from theoretical and experimental methods. : When sandy soil subjected to cycle-loading, compression of foundation and diffusion of vertical stress increment(${\Delta}{\sigma}_2$) were influenced by magnitude of loading plate. When sandy soil subjected to reloading after removing of pre-loading, the distribution of ${\Delta}{\sigma}_2$ depth at one time of loading plate width was different from its distribution at more deep point cause of load hysteresis, so in case of design of structure, the effect of ${\Delta}{\sigma}_2$ as depth must be considered. The increment of vertical stress will be different as loading condition and foundation depth, the loading condition must be considered in case of structure design.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1996.10a
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• pp.78-85
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• 1996

The effect of vertical vibration of a beam is significantly influenced by higher modes of vibration. Therefore, a beam can be modeled using several elements must De used to represent a vibrating beam. As a result, analysis of a space framed structure for vertical vibration requires increase number of elements leading to more complicated model with many degree of freedom which requires large amount of computing resources for dynamic analysis. An efficient analysis method for vertical vibration of space framed structures are proposed in this paper which is presented in three method. The first method is to determine minimum nodes that shall be used to obtain dynamic response with the vertical vibration. Secondly, matrix condensation methods are introduced to reduce the computation efforts used to perform dynamic analysis and the selection of primary degree-of-freedom is proposed. The third method is of using the mass participation factor for the selection of primary degree-of-freedom.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.10a
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• pp.469-475
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• 2004

The vibration on building structures due to exciting vibration forces has been studied only for the vibration level on existing buildings. Recently, several researches have been performed on the prediction of vertical vibration on structures by using an analytical method. However, these studies have been focused on mainly the vibration analysis through analytical modeling of structures. This study aims to investigate the dynamic characteristics of vertical vibration transfer from lower stories to upper ones on the Rahmen building structures due to traffic loads. In order to examine the characteristics of vertical vibration transfer, the mode analysis and the impact experiment were conducted several times on one building structures. The results of this study suggest that the characteristics of vertical vibration transfer are different in terms of the type of trains.

• The Journal of the Korean dental association
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• v.54 no.6
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• pp.438-446
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• 2016

Severe tooth wear may cause the pathologic change of the TMJ and masticatory muscles, unesthetic facial appearance, pathogenic pulp and occlusal disharmony. Treating patients with severely worn dentition often requires full mouth rehabilitation with increasing vertical dimension. Proper diagnosis and treatment planning are important for esthetic and functional definitive restorations and the long term stability of the neuromuscular system and the TMJ. In this case, 66 year-old female presented with generalized worn dentition. Based on assessment, pathologic destruction of teeth structure on entire dentition was caused by masticatory force and diet habit without loss of vertical dimension. Subsequently, 3 mm increase of vertical dimension that based on incisor for tooth restoration and esthetic improvement was determined. After 8 weeks stabilization period with temporary fixed prostheses, definitive prostheses were fabricated. After 6 months follow up period, satisfactory outcomes were attained both functional and esthetic aspects through this procedure.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.118-123
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• 2000

This experimental study was conducted to figure out the characteristics of convective heat transfer in non boiling vertical downward flow with polymer additives. This experiment was studied in 26mm diameter, 800mm heating length and $1{\times}10^5W/m^2$ heat flux. The polymer concentration ranged from 0PPM to 500PPM with corresponding from Reynolds number $3.3{\times}10^4$ to $6.8{\times}10^4$ in non boiling vertical downward flow. Experimental results show that the characteristics of convective heat transfer was a strong function of polymer concentration and it has decreased with increasing the polymer concentration in non boiling vertical downward flow.