• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.1
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• pp.34-42
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• 2001

A battery is the device that transforms the chemical energy into the direct-current electrical energy directly without a mechanical process. Unit cells are connected in series to obtain the required voltage, while being connected in parallel to organize capacity for load current and to decrease the internal resistance for corresponding the sudden shift of the load current. Because the voltage droop down in one set of battery is faster than in tow one, it amy result in the low efficiency of power converter with the voltage drop and cause the system shutdown. However, when the system being driven in parallel, a circular-current can be generated. The changing current differs in each set of battery because the system including batteries, rectifiers and loads is connected in parallel and it makes the charge voltage constant. It is shown that, as a result the new batteries are heated by over-charge and over-discharge, and the over charge current increases rust of the positive grid and consequently shortens the lifetime of the new batteries. The difference between the new batteries and old ones is the amount of internal resistance. In this paper, we can detect the unbalance current using the micro-processor and achieve the balance current by adjusting resistance of each set. The internal resistance of each set becomes constant and the current of charge and discharge comes to be balanced by inserting the external resistance into the system and calculating the change of internal resistance.

• Journal of Korean Library and Information Science Society
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• v.39 no.1
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• pp.5-32
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• 2008

The purpose of this study is to investigate the feasibility of establishing the national reciprocal borrowing scheme for academic libraries in Korea. The national or regional borrowing schemes could be operated to further the resource sharing among academic libraries as an alternative or supplement to ILL. In this research, the characteristics of those borrowing schemes in other countries are discussed, and some strategic plans, including the organization in charge and the operating principles, are suggested for the national borrowing scheme in Korea.

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.4
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• pp.1-8
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• 2014

The purpose of this study is to analyzes the administration actual situation of community living home in Korea. The results are as follows. First, community living home in Korea is distributed over the Jeonranam-do areas by approximately 67.7%, and distributed over 18 cities in the Jeonrabuk-do areas. Second, In a type of community living home, "Sharing residence type" accounts for approximately 97%. The reason of this is because it can save a budget by utilizing existing public accommodation. Third, the administration main constituent of community living home running in each city is a neighborhood association, but bears the administration expense in the local government. Fourth, as a result of having analyzed the representative example of the community living home, "Sharing residence type" knew that a per person necessary area was the insufficient. Finally, it is desirable for oneself of the neighborhood association to be in charge of the administration main constituent of the community living home basically.

• The Transactions of the Korean Institute of Power Electronics
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• v.19 no.1
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• pp.15-22
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• 2014

Recently, parallel operation of dc-dc converters has been widely used in distributed power systems. In this paper, a control method to achieve parallel operation of three-phase bi-directional isolated interleaved dc-dc converters is discussed for the battery charging and discharging system which consists of the 32 battery charger/dischargers and two three-phase bi-directional isolated interleaved dc-dc converters. In the boost mode, the battery energy is delivered to the grid, whereas the grid energy is transferred to the battery in the buck mode operation. The average current sharing control method is employed to obtain an equal conducting of each phase current in the three-phase dc-dc converter. By using the proposed method, the imbalance factor is gratefully reduced from 8 percent to 1 percent. Two 2.5kW three-phase bi-directional dc-dc converter prototype have been built and the proposed method has been verified through experiments.

• Journal of the Korean Institute of Gas
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• v.8 no.2 s.23
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• pp.28-34
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• 2004

Enhanced methodologies for process diagnosis and abnormal situation management have been developed for the last two decades. However, there is no single method that always shows better performance over all kinds of diagnostic problems. In this paper, a framework of message-passing, cooperative, intelligent diagnostic agents is presented for improved on-line fault diagnosis through cooperative problem solving of different expertise. A group of diagnostic agents in charge of different process functional perform local diagnoses in parallel; exchange related information with other diagnostic agents; and cooperatively solve the global diagnostic problem of the whole process plant or business units just like human experts would do. For their better understanding, sharing and exchanging of process knowledge and information, we also suggest a way of remodeling processes and protocols, taking into account semantic abstracts of process information and data. The benefits of the suggested multi-agents-based approach are demonstrated by the implementations for solving the diagnostic problems of various chemical processes.

• Fashion & Textile Research Journal
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• v.22 no.6
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• pp.777-788
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• 2020

Growth in the sharing economy and sustainability have grown has influenced collaborative consumption that values usage rather than ownership. Collaborative fashion consumption platforms have become a rapidly growing business and need to be investigated. A theoretical review and case study were conducted to analyze the typology of collaborative fashion consumption consisting of renters, lenders, and platforms. Applying the nascent literature of partial organization, this paper outlines a typology, user-driven types in which lenders take responsibility to manage rental products and platform-driven types in which platforms are in charge. Four representative cases such as Hurr Collective, Villageluxe, Wardrobe, and Closetshare were selected in order to derive the roles of collaborative fashion consumption platforms. First, it is critical to balance between renters and lenders in collaborative fashion consumption platforms. Second, it is imperative to establish trust about the platform and formulate mutually understandable guidelines. Third, the concept of lenders needs to be broadened to individuals as well as fashion brand companies. Fourth, it is necessary to improve interaction between renters and lenders in platform-driven types. This study represents one careful step to understand collaborative consumption platforms that also provides managerial and academic implications.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.4
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• pp.63-69
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• 2012

This paper describes novel scheme of a gray scale capacitive fingerprint image for high-accuracy capacitive sensor chip. The typical gray scale image scheme used a DAC of big size layout or charge-pump circuit of non-volatile memory with high power consumption and complexity by a global clock signal. A modified capacitive detection circuit of charge sharing scheme is proposed, which uses DLC(down literal circuit) based on a neuron MOS(vMOS) and analog simple multiplexor. The detection circuit is designed and simulated in 3.3V, $0.35{\mu}m$ standard CMOS process. Because the proposed circuit does not need a comparator and peripheral circuits, a pixel layout size can be reduced and the image resolution can be improved.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.33 no.4
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• pp.115-137
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• 2022

This research aims to suggest the way of activation of book curation in secondary school libraries by analyzing examples of book curation and the recognition of the persons in charge of secondary school libraries. A documentary research and a survey is conducted. 192 school librarians are chosen for that survey in Incheon region secondary school. 4 teacher librarians of Incheon region secondary school and a professor of library and information science are interviewed. Also an investigation is executed by visiting school libraries. Augmentation of the persons in charge of secondary school libraries, coordinating and information sharing with educational teachers, establishment of manual for book curation operation, publishing examples of subject selection are suggested for the measure of activation of book curation.

• Journal of Korean Library and Information Science Society
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• v.37 no.1
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• pp.109-130
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• 2006

This study aims to find the way how to operate cataloging work effectively and share it between libraries through web based cataloging manual. There have been various trials in using web based tools in ether parts of library such as acquisition and reference service. However, in case of cataloging. the rules and policies of each library are not united. and any cooperation In sharing them between libraries is not done. Therefore. for Information sharing, practical cooperation and unification in cataloging work, each library needs to make web cataloging manuals and share them. That is, building the web based cataloging tools makes it easier to access the cataloging works and keep them updated. Additionally, it could improve the communication between the librarians who are in charge of cataloging and provide the chance for cooperation and information sharing between libraries. With these roles, web based cataloging manual could be the basic for standardization of cataloging.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04b
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• pp.239-244
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• 1999

aluminum sulfate (alum) as a representative retention aid in papermaking processes was added to pulp suspensions, and the aluminum components adsorbed on the pulp were investigated quantitatively by two types of X-ray elementary analyses with regard to simultaneous changes of their surface charges. X-ray photoelectron spectroscopy (XPS) and X-ray fluorescence analysis (XFA) were applied to determine the aluminum components retained in pulp pads up to ca. 10 nm and 100${\mu}$m depth, respectively. In other words, XPS was utilized to analyze the outermost surface layers of the samples, and XFA was available for measurement of their extensive regions. A particle charge detector (PCD) was used to monitor streaming potentials at various pHs of the pulp mixtures under moderate sharing conditions. At pH 4.5 of pulp suspensions containing alum, surface charges of pulp fibers varied from negative to slight negative (approximately neutral) according to adsorption of aluminum components onto the pulp fibers. Subsequently, when a dilute NaOH solution in limited amounts was added to pulp mixtures, both streaming potentials and surface aluminum content of the pulp fibers increased distinctly although little total aluminum retention increased. Further addition of alkali solutions brought drastic decreases of the surface charges and surface aluminum content, while total aluminum content, on the contrary, increased gradually under neutral conditions. These results indicate that residual aluminum ions remained in pulp suspensions are predominantly adsorbed on surfaces of pulp fibers by adequate alkali additions and they must sufficiently cationize the fiber surfaces with increases of somewhat cationic aluminum complexes formed on the surfaces. On the other hand, aluminum components formed in higher pH ranges have nearly no contribution to improvement of charge properties of the pulp fiber surfaces, even though aluminum retention in pulp pads increases. XPS and XFA analyses combined with streaming potential measurement using a PCD suggest close relationships between aluminum content on the pulp fiber surfaces and their charge properties.