• Journal of the Korean Solar Energy Society
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• v.35 no.4
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• pp.67-75
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• 2015

PV module is conventionally connected in series with some solar cell to adjust the output of module. Some bypass diodes in module are installed to prevent module from hot spot and mismatch power loss. However, bypass diode in module exposed outdoor is easily damaged by surge voltage. In this paper, we study the thermal and electrical characteristics change of module with damaged bypass diode to easily find module with damaged bypass diode in photovoltaic system consisting of many modules. Firstly, the temperature change of bypass diode is measured according to forward and reverse bias current flowing through bypass diode. The maximum surface temperature of damaged bypass diode applied reverse bias is higher than that of normal bypass diode despite flowing equal current. Also, the output change of module with and without damaged bypass diode is observed. The output of module with damaged bypass diode is proportionally reduced by the total number of connected solar cells per one bypass diode. Lastly, the distribution temperature of module with damaged bypass diode is confirmed by IR camera. Temperature of all solar cells connected with damaged bypass diode rises and even hot spot of some solar cells is observed. We confirm that damaged bypass diodes in module lead to power drop of module, temperature rise of module and temperature rise of bypass diode. Those results are used to find module with a damaged bypass diode in system.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.403-408
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• 2007

According as diesel automobile are produced, reduce noise and vibration that is occurred by characteristic of diesel engine, and need engine room layout optimization and research for light weight of parts. Balance Shaft Module is module parts for vehicles engine to improve performance and efficiency of engine and reduce noise and vibration. These days, an oil pump integrated balance shaft module and an oil sump integrated balance shaft module is on the rising for optimizing of engine room. In this study, produced prototype of oil pump integrated type balance shaft module, and achieved dynamic characteristic test about experimental modal analysis and noise/vibration of balance shaft module.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.729-732
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• 2002

This paper reports an experimental study around a module about forced air flow by blower($35{\times}35{\times}6mm^3$) in portable PC(10mm high, 200mm wide, and 235mm long). The channel inlet flow velocity has been varied between 0.26, 0.52 and 0.78m/s. The power input to the module is 4Wthis report, particular attention is directed to the fluid flow and adiabatic wall temperature($T_(ad)$) around a module which is under fluid mechanical and thermal influences of the module. The fluid flow around a module was visualized using PIV system. Liquid crystal thernography is used to determine the adiabatic wall temperature around a heated module on an acrylic board. Plots of $T_(ad)$ (or F) show marked effects of dispersion of thermal wake near the module.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.540-545
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• 2008

The design on balance shaft module is performed based on the target specification of engine module as well as the its own dynamic nature under a high speed rotation. However, the specific information for engine module is not always available for non-motor companies even though a reliable analytical result should be attached in the conceptual design process or more detail works. In this paper, the analysis on balance shaft module, both each parts or module itself, is suggested to estimate the performance on the target component with respect to durability and NVH without any consideration of a engine module. This methodology could modify the nominal balance shaft model before the production of prototype such that cost reduction as well as time saving can be expected during design process of balance shaft module.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.5
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• pp.804-810
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• 2016

Photovoltaic system construction of the module capacity in domestic is specified criteria to less than 105% of the inverter capacity. However, the modules are installed in the outdoor actual output is reduced due to factors such as the irradiation intensity, module surface temperature. Thus, it needs the capacity of the inverter to be designed according to the actual module output. In this paper, the first approach to find the actual module output is to analyze the actual PV system monitoring data. Next, four sites where the loss analysis, system utilization, inverter utilization, and the ratio of the inverter overload are performed using PVSYST software. By changing the ratio of the module capacity, the inverter capacity of the site B is confirmed 20% less than the module capacity. Site A, C, D are identified as the ratio of the inverter capacity is 10% less than the module capacity.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.93-98
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• 2011

A photovoltaic/thermal(PVT)collector produces both thermal energy and electricity simultaneously. The heat from PV modules should be removed for better electrical performance, and can be converted into useful thermal energy. A PVT module is a combination of PV module with a solar thermal collector which forms one device that converts solar radiation into electricity and heat. In general, there are two different types of PVT module: glazed PVT module and unglazed PVT module. On the other hand, two types of the PVT module can be distinguished according to absorber on PV module rear side: the sheet-and-tube absorber PVT module and the fully wetted absorber PVT module. The absorber collector plays an important function in PVT system. It cools down the PV module, while collecting the thermal energy produced in the form of hot water. The aim of this study is to compare the electrical and thermal performance of two different PVT collectors, one with the rectangular tube and the other with fully wetted absorber PVT collectors. For this paper, the PVT collectors with two different types of thermal absorber were made, and both the thermal and electrical performance of them were measured in outdoor, and the results were compared. The experimental results were analyzed that the thermal efficiency of the fully wetted absorber PVT collector is about 8.7% higher than the sheet-and-tube absorber PVT collector, and for the electrical efficiency, the fully wetted absorber PVT collector had about 7% higher than the rectangular tube absorber.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2609-2612
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• 2003

This paper describes a 64 channel signal generator/analyzer module that is useful for verification and testing of digital circuits. It can perform logic analyzer function and signal generator function at the same time. The 64 Channel module is implemented with single FPGA chip for miniaturization, and an USB interface is used to increase portability of the module. Multiple modules can be used in parallel for the verification of large scale circuits. Moreover, since the module is implemented as a PC based system, one can configure convenient GUI(Graphic User Interface) environment.

• Korean Journal of Mathematics
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• v.25 no.4
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• pp.587-606
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• 2017

This paper is a continuation of study semi-potentness endomorphism rings of module. We give some other characterizations of endomorphism ring to be semi-potent. New results are obtained including necessary and sufficient conditions for the endomorphism ring of semi(injective) projective module to be semi-potent. Finally, we characterize a module M whose endomorphism ring it is semi-potent via direct(injective) projective modules. Several properties of the endomorphism ring of a semi(injective) projective module are obtained. Besides to that, many necessary and sufficient conditions are obtained for semi-projective, semi-injective modules to be semi-potent and co-semi-potent modules.

• Proceedings of the KIPE Conference
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• 2014.11a
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• pp.79-80
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• 2014

In this paper, to make sure that the photovoltaic solar cell module of the system can be normal for output in each solar cell module, input and output unit is installed in the bypass device, and then through the voltage and current monitoring to determine abnormality of the solar cell module, in the case of abnormal occurring, the bypass device can be pass to the next solar module of the serial structure.

• Bulletin of the Korean Mathematical Society
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• v.48 no.1
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• pp.23-33
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• 2011

Extending the notion of McCoy rings, we introduce the class of McCoy modules. Over a given ring R, it contains the class of Armendariz modules (over R). Some properties of this class of modules are established, and equivalent conditions for McCoy modules are given. Moreover, we study the relationship between a module and its polynomial module. Several known results relating to McCoy rings can be obtained as corollaries of our results.