• Current Optics and Photonics
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• v.5 no.5
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• pp.538-543
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• 2021

The evanescent wave coupling of a microring resonator is controlled by changing the gap distance between the bus waveguide and the microring waveguide. However, the interdependence of the bus waveguide's width and the coupling is not well understood. In this paper, we investigate the dependence of coupling strength on the bus waveguide's width. The strength of the evanescent wave coupling is analytically calculated using coupled-mode theory (CMT) and numerically calculated by three-dimensional finite-difference-time-domain (FDTD) simulation. The analytic and numerical simulation results show that the phase-matching condition in evanescent wave coupling does not provide maximum coupling strength, because both phase-matching and mode confinement influence the coupling. The analytic and simulation results for the evanescent coupling correspond to the experimental results. The optimized bus-waveguide width that provides maximum coupling strength results in intrinsic quality factors of up to 1.3 × 10⁶. This study provides reliable guidance for the design of microring resonators, depending on various applications.

• Steel and Composite Structures
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• v.32 no.3
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• pp.337-346
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• 2019

The present paper tries to contribute fill the gap of application of the component method to tubular connections. For this purpose, one typical joint configuration in which just one component can be considered as active has been studied. These joints were selected as symmetrically loaded welded connections in which the beam width was the same as the column width. This focused the study on the component 'side walls of rectangular hollow sections (RHS) in tension/compression'. It should be one of the main components to be considered in welded unstiffened joints between I beams and RHS columns. Many experimental tests on double-sided I-beam-to-RHS-column joint with a width ratio 1 have been carried out by the authors and a finite element (FE) model was validated with their results. Then, some different analytical approaches for the component stiffness and strength have been assessed. Finally, the stiffness proposals have been compared with some FE simulations on I-beam-to-RHS-column joints. This work finally proposes the most adequate equations that were found for the stiffness and strength characterization of the component 'side walls of RHS in tension/compression' to be applied in a further unified global proposal for the application of the component method to RHS.

• Journal of the Korean Home Economics Association
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• v.20 no.3
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• pp.9-18
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• 1982

In this study, we attempted to make an original pattern of clothing for an abnormal type of figure, especially for the type of kyphosis. We measured the curvature of the spine of a woman with kyphosis with a Martin measuring instrument and a silhouetter in the following ways. First, we counted the rate of shrinkage of the standard lines drawn on the surface of the body according as the body moved. Secondly, placing the front and back darts, the front and back shoulder darts and the side darts according to“Munhwa”pattern, we made cubic cuttings of four moving postures as well as the standing one. Thirdly, we superposed the developed patterns of the standing and the moving postures, measuring the position change and the amount of the chaange of the darts, and compared them. The results are as follows: 1) In the developed pattern of a cubic cutting of the basic pattern and the standing posture, the neckhole became larger than that of the basic pattern, and the waist line was lowered than that of the basic pattern because the center back line was shortened due to the curved backbone. 2) As for the change of the standard line according to the movement, we found that the waist line, the center front line, the center back line, the bust width line, the upper back width line and the back width line became longer. Special consideration must be given to the function of the clothing for an abnormal type of figure. 3) The difference of the measurements between the cubic cutting and the body measurement regardless of the body movement is due to a gap by an acute angle at the jutted place between the developed pattern and the body surface. We found that the body measurement of the upper back width line, the back width line and the bust line became larger. Consequently, in making an original clothing pattern, it is desirable that we must not place the front and the back waist darts at the jutted place on the back from the functional and the aesthetic viewpoint of clothing. It is also desirable that we must widen the neckhole because the shoulder angle is close to a straight line due to a jut of the upper back width line.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.11
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• pp.575-580
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• 2001

In this paper, using $500\mum-thickness\; (100)\; silicon\; wafer,\; flat\; 65\mum-thickness$ silicon mirror plates were fabricated through dry etching and wet etching, and $45\mum-depth$ grooved driving electrodes were fabricated through UV-LIGA process. Four shapes of the driving electrode were fabricated: twenty four grooves of the $50\mum-width$, twelve grooves of the $100\mum-width$, six grooves of the $200\mum-width$, and no grooves on the driving electrode. Fabricated mirror plate size and spring size are $2400\times2400\times65\mum3\; and \;500\times10\times65\mum3,$ respectively. Mirror plate parts and driving electrodes were assembled into the scanning mirrors. Measured natural resonance frequencies were about 600Hz which have error within $\pm 2%$ to calculated value. Due to the squeeze effect in the narrow gap between the mirror plate and the driving electrode, measured resonance frequencies were reduced as raising the amplitude of the mirror plate. In a case of driving electrode without grooves, the resonance frequency was reduced largely, compared with a case of driving electrode with grooves. According to the experimental results, squeeze effect was smaller in the driving electrode with smaller-width and many grooves. Therefore, the driving electrode with smaller-width and many grooves was effective in low voltage and high speed operation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.7
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• pp.1255-1260
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• 2009

Microstrip interdigital filter is designed with the width and length of a resonator, the gap distance between resonators and the location of a tap. When designing filters, it is a benefit to design with few design parameters comparing to many design parameters. In this paper we design and implement two microstrip interdigital filters operating in the UWB(Ultra Wide-Band) frequency band, one using a fixed width of a resonator and the other using a different width of resonators. The test results of the implemented filters show that the low-band high filter with a fixed width has the insertion loss of 1.49dB, -10dB band width of 720MHz, -35.7dBattenuation at 4.8GHzand below -13dB of S11. The filter with a different width of resonators has the insertion loss of 1.6dB, -10dBbandwidth of 1.63GHz and below-8dBof S11.

• Journal of Sensor Science and Technology
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• v.13 no.4
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• pp.277-281
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• 2004

$Hg_{1-x}Cd_{x}Te$ (MCT) was grown by hot wall epitaxy. Prior to the MCT growth, the CdTe (111) buffer layer was grown on the GaAs substrate at the temperature of $590^{\circ}C$ for 15 min. When the thickness of the CdTe buffer layer was $5{\mu}m$ or thicker, the full width at half maximum values obtained from the x-ray rocking curves were found to significantly decrease. After a good quality CdTe buffer layer was grown, the MCT epilayers were grown on the CdTe (111)/GaAs substrate at various temperatures in situ. The crystal quality for those epilayers was investigated by means of the x-ray rocking curves and the photocurrent experiment. The photoconductor characterization for the epilayers was also measured. The energy band gap of MCT was determined from the photocurrent measurement and the x composition rates from the temperature dependence of the energy band gap were turned out.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.152-152
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• 2003

Hg$\sub$l-x/Cd$\sub$x/Te (MCT) was grown by hot wall epitaxy. Prior to the MCT growth, the CdTe (111) buffer layer was grown on the GaAs substrate at the temperature of 590$^{\circ}C$ for 15 min. When the thickness of the CdTe buffer layer was 5 $\mu\textrm{m}$ or thicker, the full width at half maximum values obtained from the x-ray rocking curves were found to significantly decrease. After a good quality CdTe buffer layer was grown, the MCT epilayers were grown on the CdTe (111) /GaAs substrate at various temperatures in situ. The crystal quality for those epilayers was investigated by means of the x-ray rocking curves and the photocurrent experiment The photoconductor characterization for the epilayers was also measured The energy band gap of MCT was determined from the photocurrent measurement and the x composition rates from the temperature dependence of the energy band gap were turned out

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.6
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• pp.1105-1109
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• 2009

This paper deals with a polynomial thrust equation of a permanent magnet linear synchronous motor that is considered by a skew and overhang effects of permanent magnet. The skew length, the overhang length, the width and height of permanent magnet, the teeth length and air-gap length which effect to the flux density of air-gap are selected as variables of the polynomial thrust equation. Polynomial thrust equation is elicited by the 6 parameters. The results are satisfied that the values by polynomial thrust equation are compared ones by using 3-dimensional finite element analysis and experiment.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.379-379
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• 2010

$Hg_{1_x}Cd_xTe$ (MCT) was grown by hot wall epitaxy. Prior to the MCT growth, the CdTe (111) buffer layer was grown on the GaAs substrate at the temperature of $590^{\circ}C$ for 15 min. When the thickness of the CdTe buffer layer was $5\;{\mu}m$ or thicker, the full width at half maximum values obtained from the x-ray rocking curves were found to significantly decrease. After a good quality CdTe buffer layer was grown, the MCT epilayers were grown on the CdTe (111) /GaAs substrate at various temperatures in situ. The crystal quality for those epilayers was investigated by means of the x-ray rocking curves and the photocurrent experiment. The photoconductor characterization for the epilayers was also measured. The energy band gap of MCT was determined from the photocurrent measurement and the x composition rates from the temperature dependence of the energy band gap were turned out.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.48 no.2
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• pp.56-62
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• 1999

This paper is concerned with the design and the construction of a moving magnet type linear DC motor(MM type LDM) for instrumentation. A mathematical model for the design of a LDM is developed and a permeance method is used to calculate the effective flux density in the air gap. The flux distribution in the air gap is analyzed and the width of iron core should be determined in order not to saturate the iron core by caluclating maxmum flux density. The design data culculated by a permeance method are compared with the analyzed results using FEM(MAXWELL 2D). The errors between two results are corrected. The tested LDM is constructed using the corrected design data. The results of experiment for thrust characteristics are compared with simulation.