• 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 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.

• The Journal of Fisheries Business Administration
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• v.49 no.4
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• pp.83-97
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• 2018

The ocean is very important to mankind for its infinite value in resource storage and utilization. In shallow coastal waters, landfill as well as pollution damage occurs frequently for the promotion of important public and private projects that are the driving forces of national development. In this case, compensation paid for the loss or damage of fishing rights acquired by the fishing community shall be distributed to each individual of the fishing community in accordance with the appropriate balance. In reality, as fishing communities in different sectors coexist, the voting rights of the general meeting of fishing communities are ignored as a minority, and the demand for the rights is ignored by the majority. Many other industries receive fish compensation, even though they have not suffered much damage. As a result serious conflicts between the individuals of the fishing community have caused social problems. Therefore, similar cases are investigated and analyzed to provide a reasonable solution.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.10
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• pp.701-707
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• 2000

This paper proposes a tension control to compensate friction loss using on-line friction torque observer for a continuous strip processing line. Friction loss of roller results in significant deviation of strip tension, accordingly it has an influence on the operation of other adjacent rolls. To avoid tension variation of the strip, a friction torque observer is designed in adjacent roll, which operates in speed control mode. The observed torque is added to the torque limit reference of the pay-off reel for on-line compensation of both friction loss and acceleration/deceleration torque at the same time. The simulation and experimental results show improvement of tension control performance by the proposed friction compensation method.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.5
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• pp.761-766
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• 2008

This paper describes a compensation algorithm for a measurement voltage transformer (VT) based on the hysteresis characteristics of the core. The error of the VT is caused by the voltages across the primary and secondary windings. The latter depends on the secondary current whilst the former depends on the primary current, i.e. the sum of the exciting current and the secondary current. The proposed algorithm calculates the voltages across the primary and secondary windings and add them to the measured secondary voltage for compensation. To do this, the primary and secondary currents should be estimated. The secondary current is obtained directly from the secondary voltage and used to calculate the voltage across the secondary winding. For the primary current, in this paper, the exciting current is decomposed into the two currents, i.e. the core-loss current and the magnetizing current. The core-loss current is obtained by dividing the primary induced voltage by the core-loss resistance. The magnetizing current is obtained by inserting the flux into the flux-magnetizing current curve. The calculated voltages across the primary and secondary windings are added to the measured secondary current for compensation. The proposed compensation algorithm improves the error of the VT significantly.

• The Journal of Fisheries Business Administration
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• v.37 no.3 s.72
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• pp.85-108
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• 2006

The government enforced 'Act on the acquisition of land for the public undertakings and compensation' commenced on the 1st of January 2003 to faithfully protect the property right of people and to scheme the effiecient drive of public works by systematizing the procedures and the standards of compensation and reforming irrational systems. The previous act regulated to compensate a rightful person of fishery right, who is in a nearby area of public works enforcement zone for actual loss according to the level of damage. On the contrary, as for the fishery damage happened at the outside of public works enforcement zone, the act regulates to compensate for a loss when it is actullay occurred and affirmed. So, the related act was amended as, so called, Post Factum Compensation. With regard to the Post Factum Compensation regulation for the fishery damage occurred at the outside of this public works enforcement zone, many objections and problems are raised as it is not clearly understood of the nature of the fishery compensation. However, this paper is not intended to mention the right or wrong of the current law, but to discuss the problems or remedies of 'Act on the acquisition of land for the public undertakings and compensation' after examining cases of public works which was enforced for the fishery compensation within the current law.

• Smart Structures and Systems
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• v.17 no.6
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• pp.881-901
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• 2016

In this study, a method to compensate the effect of temperature variation on impedance responses which are used for prestress-loss monitoring in prestressed concrete (PSC) girders is presented. Firstly, an impedance-based technique using a mountable lead-zirconate-titanate (PZT) interface is presented for prestress-loss monitoring in the local tendon-anchorage member. Secondly, a cross-correlation-based algorithm to compensate the effect of temperature variation in the impedance signatures is outlined. Thirdly, lab-scale experiments are performed on a PSC girder instrumented with a mountable PZT interface at the tendon-anchorage. A series of temperature variation and prestress-loss events are simulated for the lab-scale PSC girder. Finally, the feasibility of the proposed method is experimentally verified for prestress-loss monitoring in the PSC girder under temperature-varying conditions and prestress-loss events.

• The Journal of Fisheries Business Administration
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• v.25 no.1
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• pp.19-35
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• 1994

The objective of this study is to analize the system of legal compensation for the fishery loses caused by public works and to suggest alternatives on the current compensation system. Korea government has been performing reclamation activities in coastal region to conduct farm, urban and industrial area, and such activities are still going on in Yeongjongdo airport area, Saemangeum area and so on. Reclamation interrupts fishing activities in or around the reclaiming area, therefore, the compensation for fishery losses incurred by fishermen should be made. The system of legal compensation in Korea, however, is based on the land compensation, and the regulation of the compensation for fishery losses in the Fishery Act can not be applied for the compensation of public works because the procedure of the compensation in the Fishery Act is different from its cause of action. Therefore, this study is caried out to suggest a resonable compensation procedure and to provide a basis for establishing legal system.

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.523-538
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• 2013

To help improve the current government practice of direct damage-compensation policies, resulting from the loss of profit, sustained by Hanwoo farmers, as a result of the recent Korea-U. S. Free Trade Agreement (FTA), this research aims to examine any problems or issues caused by said policies. To accomplish this task, we have established Hanwoo-SIMO model and estimated the damage of Hanwoo farmers, one without the implementation of the FTA and another with the FTA, to compare and contrast the two. We then analyzed the efficacy of the current government policies. According to our analysis, the current direct compensation policies for the loss of profit on the part of Hanwoo farmers are insufficient. To address this problem, we recommend the government enact a new direct damagecompensation law to address the following issues. First, as the base formula of damage-compensation, the government should use current price of the beef rather than the annually changing flexible price. Second, the flexible control index should remain fixed at 1.0 rate while the government prepares the adequate amount of the damage compensating direct payment resulting from the FTA. Third, the direct government compensation policy should extend beyond the current 15 years (2013-2026) as the profit loss is expected to increase after the midpoint of the FTA.

• Journal of the Korean Society of Safety
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• v.34 no.1
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• pp.115-121
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• 2019

Background: Due to the diversification and advancement of research, researchers have become to deal with a variety of chemical and biological harmful materials in the laboratories of universities and research institutes and the risk has increased as well. Therefore, it is necessary to strengthen the social safety net for laboratory accidents by strengthening the compensation to the level comparable to that of Korean Workers' Compensation & Welfare Service, when the researchers become physically disabled by laboratory accidents. The purpose of this study is to secure researchers' health rights and to create a research environment where researchers can work with confidence by strengthening the compensation to the level comparable to that of Korean Workers' Compensation & Welfare Service. Method: We analyzed the laboratory accidents by year, injury type, severity of accident and disability grade with the 6 year data from 2011 to 2016, provided by Laboratory Safety Insurance. Based on the analysis result, we predicted the financial impact on Laboratory Safety Insurance if we introduce a compensation annuity by disability grade which is similar to Injury-Disease Compensation Annuity of Korean Workers' Compensation & Welfare Service. Result :As of 2011, the insured number of Laboratory Safety Insurance was approximately 700,000. The Average premium per insured was KRW 3,339 and there were 158 claims. Total claim amount was KRW 130 million, whereas the premium was about KRW 2.3 billion. The loss ratio was very low at 5.75%. If we introduce a compensation annuity by disability grade similar to Injury-Disease Compensation Annuity of Korean Workers' Compensation & Welfare Service, the expected benefit amount for 1 case of disability grade 1 would be KRW 1.6 billion, assuming 2% of interest rate. Given current premium, the loss ratio, the ratio of premium income to claim payment, is expected 41.4% in 2017 and 151.6% in 2026. The increased loss ratio due to the introduce of the compensation annuity by disability grade is estimated to be 11.0% in 2017 and 40.4% in 2026. Conclusion: Currently, laboratories can purchase insurance companies' laboratory safety insurance that meets the standards prescribed by Act on the Establishment of Safe Laboratory Environment. However, if a compensation annuity is introduced, it would be difficult for insurance companies to operate the laboratory safety insurance due to financial losses from a large-scale accident. Therefore, it is desirable that one or designated entities operate laboratory safety insurance. We think that it is more desirable for laboratory safety insurance to be operated by a public entity rather than private entities.