• Journal of Electrical Engineering and Technology
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• v.13 no.2
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• pp.769-780
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• 2018

This paper presents an analysis of the power gain under partial shading conditions (PSC) when the partial shade loss is being compensated in photovoltaic(PV) system. To analyze the power gain, our study divides the mismatch loss into partial shade loss and operating point loss. Partial shade loss is defined as the power difference between a normal string and a partially shaded string at the maximum power point (MPP). Operating point loss is defined as the power loss due to the operating point shift while following the MPP of the PV array. Partial shading in a PV system affects the maximum power point tracking (MPPT) control by creating multiple MPPs, which causes mismatch losses. Several MPPT algorithms have been suggested to solve the multiple MPP problems. Among these, mismatch compensation algorithms require additional power to compensate for the mismatch loss; however, these algorithms do not consider the gain or loss between the input power required for compensation and the increased output power obtained after compensation. This paper analyzes the power gain resulting from the partial shade loss compensation under PSC, using the V-P curve of the PV system, and verifies that power gain existence by simulation and experiment.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.3
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• pp.235-241
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• 2007

This paper proposes a self-calibration method of robots those are used in industrial assembly lines. The proposed method is a position compensation using laser sensor and vision camera. Because the laser sensor is cross type laser sensor which can scan a horizontal and vertical line, it is efficient way to detect a feature of vehicle and winding shape of vehicle's body. For position compensation of 3-Dimensional axis, we applied block interpolation method. For selecting feature point, pattern matching method is used and 3-D position is selected by Euclidean distance mapping between 462 feature values and evaluated feature point. In order to evaluate the proposed algorithm, experiments are performed in real industrial vehicle assembly line. In results, robot's working point can be displayed 3-D points. These points are used to diagnosis error of position and reselecting working point.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.7 s.184
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• pp.51-58
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• 2006

This study analyzes the uncertainty of the compensation method of a sensing error of three-DOF measuring system. This compensation method utilizes a reference coordinate system using a three point by moving a position of an endpoint of a three-DOF manipulator. The coordinate transformation between the three-DOF manipulator and the measuring system is identified by the reference coordinate system. According to the concept of this compensation method, each positioning error at any position of the end-point of the manipulator is derived. Uncertainty analyses of the compensation values on the basis of sensitivity analysis and Monte Carlo simulation are used to investigate a feasibility and effectiveness of the compensation method.

• Korean Journal of Medicinal Crop Science
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• v.9 no.3
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• pp.232-237
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• 2001

This study was carried out to know the effect of light intensity, temperature and $CO_2$ concentration on photosynthesis and transpiration in yacon(Polymnia sonchifolia Poepp.& Endl.). Light compensation point was ${58\;{\mu}mol\;m^{-2}\;s^{-1}}$and light saturation point was ${1708\;{\mu}mol\;m^{-2}\;s^{-1}}$. Transpiration rate was increased to about 4 mmol${m^{-2}\;s^{-1}}$ with increasing of light intensity to ${2193\;{\mu}mol\;m^{-2}\;s^{-1}}$. The optimum temperature for photosynthesis was ${24^{\circ}C}$ in air. Photosynthesis was gradually reduced as transpiration rate increased from 4 to 8 mmol ${m^{-2}\;s^{-1}}$ in different air temperature. $CO_2$ compensation point was 63 vpm and $CO_2$ saturation point was 1155 vpm and light saturation point was enhanced with increasing of $CO_2$ concentration from 350 vpm to 1300 vpm.

• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.15-17
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• 2006

This paper presents a new global intensity compensation method for extracting moving object in a visual surveillance system by compensating time variant intensity changes of background region. The method that compensates a little changes of intensity due to time variant illumination change and automatic gain control of camera is called global intensity compensation. The proposed method expresses global intensity change with a mapping table to describe complex form of intensity change while the previous method models this global intensity change with a simple function as a straight line. The proposed method builds the mapping table by calculating the cross histogram between two images and then by selecting an initial point for generating the mapping table by using Hough transform applied to the cross histogram image. Then starting from the initial point, the mapping table is generated according to the proposed algorithm based on the assumption that reflects the characteristic of global intensity change. Experimental results show that the proposed method makes the compensation error much smaller than the previous GIC method

• Korean Journal of Medicinal Crop Science
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• v.10 no.1
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• pp.1-4
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• 2002

This study was carried out to know the effect of light intensity, temperature and $CO_2$ concentration on photosynthesis and transpiration in Hovenia dulcis Thunb. Light compensation point was $2.4\;{\mu}mol\;m^{-2}\;s^{-1}$ and light saturation point was $1033\;{\mu}mol\;m^{-2}\;s^{-1}$. The optimum temperature for photosynthesis was $25^{\circ}C$ at $1000\;{\mu}mol\;m^{-2}\;s^{-1}$ light intensity. $CO_2$ compensation point was 67 vpm and $CO_2$ saturation point was 707 vpm. Transpiration rate was increased to about $2\;mmol\;m^{-2}\;s^{-1}$ with increasing of light intensity to $1750\;{\mu}mol\;m^{-2}\;s^{-1}$ and to above $4\;mmol\;m^{-2}\;s^{-1}$ with increasing of temperature from $18^{\circ}C$ to $36^{\circ}C$. however It was gradually reduced as $CO_2$ concentration increased from 21 vpm to 800 vpm.

• Journal of Korean Academy of Nursing Administration
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• v.9 no.4
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• pp.585-597
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• 2003

Purpose: The purpose of this research is to find out how clinical nurse's recognition is effected to nursing organization through compensation justice, and then will support important basic data to management of nursing organization. Methods: Data collection was held through April 1st to 30th in 2003, The Subjects were 375 who were working at 5 hospitals in Seoul and has experiences at least over one year. Result: The average score of nurses' organizational commitment was 3.95 on a 7 point scale, and job satisfaction was 2.80 on a 5 point scale, and distribute justice was 2 on a 5 point scale, and procedural justice was 2.32 on a 5 point scale. We realize the distribute justice of compensation justice showed outstanding difference by age, education back-ground, experience, status of job, religious and types of hospital foundation, comparing the procedural justice only showed the difference by marriage status and type of hospital foundation, Through the study of how compensation-justice effect to organizational commitment, distribute justice never effect instead of procedural justice made effect 30.4% overall transition, as well as procedural justice explain 31.5% of job satisfaction. Conclusion: Finally we have data on the clinical nurse's recognition of compensation justice distribute justice and procedural justice are generally low, job satisfaction and organizational commitment are average. Job satisfaction and organizational commitment are depend upon age and educational level seriously.

• Journal of Power Electronics
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• v.18 no.6
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• pp.1866-1878
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• 2018

This paper presents a neutral point deviation and ripple compensation control method for application to 3-level NPC converters. The neutral point deviation and its harmonic components are analyzed with a focus on the average current flowing through the neutral point of the dc-link. This paper also proposes a control scheme to compensate for the neutral point deviation and dominant harmonic components under generalized unbalanced grid operating conditions. The positive and negative sequence components of the pole voltages and ac input currents are employed to accurately explain the behavior of 3-level NPC converters. Simulation and experimental results are presented to verify the validity of the proposed method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.6C
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• pp.492-496
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• 2012

This paper presents a decoding technique for speech recognition using uncertainty information from feature compensation method to improve the speech recognition performance in the low SNR condition. Traditional feature compensation algorithms have difficulty in estimating clean feature parameters in adverse environment. Those algorithms focus on the point estimation of desired features. The point estimation of feature compensation method degrades speech recognition performance when incorrectly estimated features enter into the decoder of speech recognition. In this paper, we apply the uncertainty information from well-known feature compensation method, such as IMM, to the recognition engine. Applied technique shows better performance in the Aurora-2 DB.

• Journal of the Korean Solar Energy Society
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• v.29 no.1
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• pp.58-63
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• 2009

In this paper, the power loss due to PV module mismatch in PV string is analyzed and a mismatch compensation method is proposed to improve the efficiency of PV system. The analysis of mismatch loss using PV model simulation reveals that the mismatch module may decrease the total efficiency because the MPPT function of power conditioner make the PV system operate at the local maximum point. The mismatch loss can be severe if the maximum power point current of mismatch module is less than that of string. The proposed compensation method which is simply implemented with a buck type converter shows the possibility to remove the mismatch loss. The effectiveness of the analysis and compensation method is verified by a prototype experiment.