• Journal of Biosystems Engineering
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• v.40 no.4
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• pp.327-334
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• 2015

Purpose: A falling-type weight sorter equipped with a load cell was developed to sort lightweight dried persimmons. The performance of the sorter was also evaluated. Methods: The electronic weight sorter for dried persimmon comprises a feeder part, a weight-measurement part, an indicator part, a carrier cup, a discharging part, and a driving part. The weight setting and zero-point adjustment are performed digitally for the convenience of users. For the experimental trials, 228 rubber-clay specimens (representative of dried persimmons) in the weight range of 24.73~99.56 g were manufactured for use in experiments to evaluate the performance of the sorter. Results: The average error of the weight measurements from three experimental trials was 1.655%, with a bias of -0.492 g, a root-mean-square error (RMSE) of ${\pm}0.808g$, and a coefficient of determination ($R^2$ ) of 0.997. Conclusions: The load-cell-based electronic dried-persimmon weight sorter developed in this study facilitates effective, precise, and convenient sorting of dried persimmons.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.1
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• pp.87-94
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• 2005

This paper is about the compensation of phase angle error and amplitude difference in stationary 2 pole coordinates by the installation variation of sensor at low cost high resolution digital hybrid encoder. To solve the problem of amplitude difference at the existing hybrid encoder, we normalized the relative magnitude of the two analog signals. and also to solve the problem of installation variation when installed the sensor, we rotate the stationary 2 pole coordinates to compensate the location error of sensor. and we used and tested the QEP function and A/D port in DSP(TMS320F2812) to verify the mentioned proposed method.

• Korean Journal of Optics and Photonics
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• v.10 no.4
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• pp.342-347
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• 1999

As the waveguide width and the radius of curvature get smaller for the effort of monolithic fabrication of integrated photonic devices, the waveguide characteristics change significantly according to the change of the waveguide width or the radius of curvature. Especially, variation of the waveguide width due to fabrication process errors induces a phase error for each waveguide from the change of the propagation constant. Therefore, it is important to quantify these variation effects on the device characteristics for the design and fabrication of highly integrated photonic devices. Here, we analyze four different types of waveguides to get general characteristics in propagation constant change by utilizing the effective index method and the analytic solution method. Futhermore, the output characteristics of two AWG(Arrayed Waveguide Grating) devices are simulated by a highly-functional computer code. The simulated results have been found to be similar to the realistic device characteristics. The required fabrication error limit for the ridge-type InP-AWG device should be smaller than 0.02 ${\mu}{\textrm}{m}$ to get better channel crosstalk than-25 dB, while the required fabrication error limit for rib-type silica-AWG devices may be allowed up to 0.1 ${\mu}{\textrm}{m}$ to obtain better crosstalk than -30 dB.

• Communications of the Korean Mathematical Society
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• v.11 no.2
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• pp.503-514
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• 1996

We consider non-constant coefficient elliptic equations of the type -div(a \bigtriangledown u) = f$, and employ the P-version of the finite element method as a numerical method for the approximate solutions. To compute the integrals in the variational form of the discrete problem we need the numerical quadrature rule scheme. In practice the integrations are seldom computed exactly. In this paper, we give an $L_2(\Omega)$-error estimate of $\Vert u = \tilde{u}_p \Vert_{0,omega}$ in comparison with $\Vert u = \tilde{u}_p \Vert_{1,omega}$, under numerical quadrature rules which are used for calculating the integrations in each of the stiffness matrix and the load vector.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.8
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• pp.1167-1177
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• 1989

In this paper, a generalized adaptive law is proposed which uses a rational function type operator for parameter adjustment. To satisfy the passivity condition of the adaptation block, we introduce a constant feedback gain into the adaptation block. This adaptation scheme is applied to the model reference adaptive control of a continuous-time, linear time-invariant, minimum-phase system whose relative degree is 1. We prove the asymptotic stability of the output error of this adaptive system by hyperstability method. It is shown that by digital computer simulations this law can give a better output error transient response in some cases than the conventional gradient adaptive law. And the output error responses for the several types of the proposed adaptation law are examined in the presence of a kind of unmodeled dynamics.

• Journal of the Korean Society of Safety
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• v.11 no.3
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• pp.10-19
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• 1996

Grinding temperature and thermal deformation(dimensional error) are studied theoretically and experimentally. The propose of this research is clarified loading phenomena and residual stress In order to guide nozzle's efficiency. The main results to be obtained are as follows ; 1) When grinding condition Is high efficient grinding, FEM program is developed about grinding heat and dimensional error. 2) Thermal deformation depend on temperature distribution is in good agreement with experimental results in case of little grinding energy flux but is comparatively in good agreement with in case of large (3.5$\times$10$^{6}$ J/m). 3) In terms of high efficient grinding at field(table speed 4m/min), grinding fluid (dilution 5/100) obtained a good workpiece quality and decreased a grinding temperature. 4) A surface roughness, dimensional error, residual stress and loading phenomena with guide nozzle are decreased and these results obtained a good workpiece quality.

• Journal of Environmental Science International
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• v.13 no.7
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• pp.637-643
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• 2004

A new method of automatic recording raingauge is developed to measure rainfall with 0.01mm resolution. This use two different signals to measure rainfall more accurately compare than other raingauges. One is weight of the tipping bucket with rainfall amount and the other is pulse from tipping bucket reverse. New method applied 1 mm tipping bucket mechanism and install loadcell under tipping bucket mechanism for measuring rainfall weight. Loadcell measure weight of rainfall until 1 mm with 0.01 mm resolution and more than 1 mm than bucket reverse and pulse signal generate, after that loadcell measure weight again. The validation of new instrument was examined in the room 65 mm/hour rainfall rate total 53 mm range. There is below than 1 % error of absolute rainfall amount and 0.01 mm resolution. The field test of instrument was carried out by comparing its measured values with values recorded by weight type and standard type on June 1 2003 at Terrestrial Environmental Research Center at Tsukuba University in Tsukuba of Japan, when it has recorded total amount of 40.58 mm rainfall by standard raingauge and new raingauge recorded 41.032 mm. Same rainfall intensity pattern observed in field observation with weight type raingauge. Rainfall intensity between weight type and Lee-A type raingauge reached 0.9947 correlation in 3 minute average.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.1-7
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• 1993

In this paper we propose the new adaptive control algorithm by using S-G algorithm based on the error equations derived by Slotine. We verify the validity of the proposed controller and convergence of three type parameter estimation law based on S-G algorithm from the computer simulation.

• Journal of applied mathematics & informatics
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• v.14 no.1_2
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• pp.473-484
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• 2004

In this paper we give an expression for the kernel and remainder term of Gauss-Radau and Gauss-Lobatto quadratures and study on an error bound with end points of multiplicity γ.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.7
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• pp.1109-1120
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• 2009

This study develops a fitted torso type basic pattern for men by utilizing 3D body scan data. Recent fashion trends are reflected in the development of the pattern. The subjects were 15 men in their 20's, who wear size 95 (M size). Body scan data was obtained through a 3D whole body scanner (WB4, Cyberware, USA), and a body surface development figure for developing male fitted torso type basic pattern was attained through the use of Rapid Form 2006 as well as Auto CAD 2006 programs. The results are as follows: A body surface development figure through body surface segment method showed high exactitude in an error range of 100$\pm$1%. In addition, it occurred in an error range of 100:1:3% because of the hard scanning conditions in the incline of the shoulder and armpit areas. However, the body surface development figure as well as the direct measurement results can be used as basic data for the given patternmaking since the error range falls into 100$\pm$3%. Dart amounts obtained from the average cross section were center back 2.2cm (24.3%), back armpit point 3.8cm (41.8%), front armpit point 3.0cm (33.9%). As shown the jacket pattern, the biggest dart amount was portioned out at the back armpit point. The drafting equations for the development pattern acquired are as follows; Full width=C/2+5cm, back length=height/4-1cm, armhole depth=(C/10+12cm)+3cm, back width=2C/10+2cm, front width=2C/10. The development pattern was a fitted torso basic pattern that was composed of 3 pieces, so it would be very useful in developing shirt or jacket patterns. According to the results of the evaluation of the developed pattern appearance, it obtained higher scores of over 3.5 points in almost items, meaning that the developed pattern is appropriate for a male fitted torso type basic pattern. It suggests a possibility of patternmaking from a body surface development figure in 2-D to prototype.