• KEPCO Journal on Electric Power and Energy
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• v.8 no.2
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• pp.61-68
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• 2022

In this paper, the change history of various types of MV (Medium Voltage) cables was investigated. In addition, the statistical life expectancy of each type was calculated by using the operation data and the failure data. For cut-off year, 10 years was applied, and realistically applicable statistical life expectancy was calculated by correcting the cause of failure entered by mistake. The life expectancy of FR-CNCO-W was calculated as 51.2 years, CNCV-W 38.1 years, and CNCV 31.4 years and the overall average is 33.8 years. Currently, the life expectancy of TR CNCV-W is 29.4 years, but it is estimated that the lifespan will be extended if failure data is accumulated. As a result, it is expected that life expectancy results can be applied to Asset Management System (AMS) in the future.

• Geomechanics and Engineering
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• v.33 no.1
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• pp.53-63
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• 2023

Rock disturbance caused by blasting and stress relaxation is commonly observed during excavation. As the distance from the source of disturbance increases, the degree of disturbance decreases, and rock at a large depth does not experience disturbance. However, in stability analyses, a single value of disturbance is often applied to the entire rock mass, which leads to underestimated results. In this study, this modeling mistake is addressed by considering realistically varying rock disturbance. The safety of infinite slopes in a disturbed rock mass with a strength governed by the Hoek-Brown failure criterion is investigated based on the kinematic approach of limit analysis. The maximum disturbance is assigned to the outermost slope face because it is directly exposed to blasting damage and dilation, and the disturbance progressively decays with distance in the rock mass. The safety analysis results indicate that the assumption of uniform disturbance in the entire rock mass leads to underestimation of the rock strength and safety on infinite rock slopes. A critical slip surface appears to be within the disturbed rock layer as well as the interface between the disturbed upper rock and undisturbed lower rock.

• Journal of Korea Society of Industrial Information Systems
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• v.15 no.5
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• pp.1-9
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• 2010

Abstract The DHCP power saving system provides advantage to driving active participation in which users installs the power saving software by restricting IP address through the power management server. However, the problem with this approach is the vulnerability to IP spoofing attacks, therefore we need to solve the mistake that disrupt the entire network system rather than saving electric power. In this paper, we propose the authentication system that can implement the efficiency saving power by providing high security for the members' computer system of the public institutions based on the saving power system.

• Communications of the Korean Mathematical Society
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• v.38 no.1
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• pp.121-122
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• 2023

In this erratum, we correct a mistake in the proof of Proposition 2.7. In fact the equivalence (3) ⇐ (4) "R is a quasi-regular ring if and only if R is a reduced ring and every principal ideal contained in Z(R) is a 0-ideal" does not hold as we only have Rx ⊆ O(S).

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.167-168
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• 2023

Construction of reinforced concrete structures required massive amounts of concrete and steel rebar. The current procedure to estimate the quantity of rebar requires tedious and time-consuming manual labor. Consequently, this circumstance made the engineers vulnerable to error and mistake, which led to the rebar waste. No system that is capable of automatically calculating rebar length has yet been developed Thus, this study proposes a preliminary investigation of automatic rebar length estimation of beam element by using BIM-based shape codes drawn in Revit. Beam is chosen due to its complexity in the rebar arrangement. In addition, the development of this study could assist engineers on the construction site and effectively contribute to the minimization of rebar waste in the future.

• International Journal of Computer Science & Network Security
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• v.24 no.8
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• pp.72-84
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• 2024

Plant leaf classification is an imperative task when their use in real world is considered either for medicinal purposes or in agricultural sector. Accurate identification of plants is, therefore, quite important, since there are numerous poisonous plants which if by mistake consumed or used by humans can prove fatal to their lives. Furthermore, in agriculture, detection of certain kinds of weeds can prove to be quite significant for saving crops against such unwanted plants. In general, Artificial Neural Networks (ANN) are a suitable candidate for classification of images when small datasets are available. However, these suffer from local minima problems which can be effectively resolved using some global optimization techniques. Considering this issue, the present research paper presents an automated plant leaf classification system using optimized soft computing models in which ANNs are optimized using Grasshopper Optimization algorithm (GOA). In addition, the proposed model outperformed the state-of-the-art techniques when compared with simple ANN and particle swarm optimization based ANN. Results show that proposed GOA-ANN based plant leaf classification system is a promising technique for small image datasets.

• Journal of Science Education
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• v.32 no.1
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• pp.33-46
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• 2008

The purpose of this study was to know whether or not any wrongful description or simple errors were in photosynthesis unit of Biology II textbook under 7th national curriculum and if so, to know whether or not high school teachers recognized and corrected properly the mistakes. The mistakes in photosynthesis unit of text books were determined by the comparison with several reference books and through examination by three plant physiologists in 8 different Biology II textbooks. After the mistakes were analysed, the survey using contents of textbook containing the mistakes was conducted on high school teachers teaching Biology II. As a result, 48 mistakes were determined in 13 subjects. As many as four mistakes were found even in one subject in a certain textbook and a same mistake was found repeatedly in several textbooks. The survey result showed that the teachers who pointed exactly the mistakes out corrected properly, however, the percentage of these ones out of 35 teachers replied to survey was less than 50%. The ratios of correction out of total number of responses were high in question #6 (43%), #4-3 (40%), and #1-2 (32%) which were containing a simple mistake in graph, a wrong word and a wrong picture, respectively. But, no one pointed out and made correction in question #5-1 and #5-2 which were containing Z scheme of light reaction without the legend of vertical axis that should be explained as electron energy or standard reduction potential. The result indicates the possibility that the mistakes in photosynthesis unit of Biology II textbook can be corrected and teached properly by teachers may be low. In order to reduce the possibility that students may have misconceptions about photosynthesis, the list of print's errors should be provided to the teachers and/or the training program and/or workshop for in-service high school biology teachers was recommended.

• The Journal of Art Theory & Practice
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• no.9
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• pp.59-91
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• 2010

The Bauhaus educational method gave the strong influences on Modern Japanese art and design education. In the 1920s and 1930s, Japan allied with Germany and Italy politically and tried to receive German system to be modernized. The reception of the Bauhaus and Moholy-Nagy's photographic theory was one of those activities at that time. Japanese intellectual class went to the Bauhaus and studied there; Ishimoto Kikuchi, Nakata Sadanosuke, Mijutani Takehiko, Yamawaki Iwao and Yamawaki Michiko(Yamawaki Iwao's wife). Especially, Yamawaki Iwao studied about the architecture at the Bauhaus, but his interest moved toward the photography and the photomontage based on Moholy-Nagy's theory. He studied at the photography workshop of the Bauhaus presented by Peterhans irregularly. Even though Yamawaki Iwao was an architect, he wanted to be admitted as an expert for the photomontage that he particularly studied at the Bauahus as a Bauhaus member. He had presented many articles about the photomontage at the photography magazines in Japan in order to introduce it to Japan since he returned in 1933. Thus, Yamawaki Iwao is the important person when we look back the Modern Japanese design and art history. In Japan, the art and design systems are managed by the Bauhaus educational system until now, and it has become a kind of cultural legacy in Modern Japan; The university of Tama and The university of Tsukuba are the representative educational systems which are based on the Bauhaus legacy. However, Yamawaki Iwao had been concealed as a photographer in Japanese design and photography history until the retrospective discuss named by 'Bauhaus syashin(Bauhaus Photographies)' at the photography magazine, Deja-vu in 1995 and the retrospective exhibition titled as 'Bauhaus syashin(bauahustofografie)' in 1997. This study rethinks of Yamawaki Iwao's historical position while looking at the term as 'Bauhaus Syashin(Bauhaus Photographies)' used in Japan. It is very important to bear in mind Moholy-Nagy's wide variety of approaches to photography at the Bauhaus, but it is impossible to name it 'Bauhaus style'. 'Bauhaus style' is the international style in architecture, but that was never a Bauhaus style in photography. Eugene J. Prakapas indicated that the vague term of 'Bauhaus Photographies' in his article in 1985 as well. This study considers the historical background for the mistake of the term of 'Bauhaus Syashin(Bauhaus Photographies)' in Modern Japanese history, while looking at Yamawaki Iwao's photomontage faintly entering on the historical stage again to discuss the reception of the photomontage from him. In particular, Some of Yamawaki Iwao's photomontage presented as the wall photography in Japan during the Second World War, that was related to the propaganda of Japanese government. It had not been known well in the modern Japanese art and design history because it was related to a declaration of the Second World War by Japan. However, the historical position of his photomontage is very important for Japanese history when we rethink of the reception of the Bauhaus and Moholy-Nagys' photographic theory to build up the Japanese modern history. In the result, this study wants to discuss that the mistake of the term of 'Bauhaus syashin(Bauhaus Photographies)' in Japan is related to the interpretation for the the historical position for Yamawaki Iwao's photomontage in the reception of Bauhaus and Moholy-Nagy's photography in Japan.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.41
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• pp.79-102
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• 2009

L/C transaction, the most important issue for the seller and the buyer is the theory of documentary transaction and the theory of strict compliance which are the principles of L/C transactions. According to the leading cases in England and America where the practice of L/C transactions was created and developed, the descriptions of the commodities specified on all the documents which are submitted based on an L/C, should be identical to the descriptions of commodities specified in the L/C. And further, many leading cases of L/C continuously repeat to emphasize strict compliance. However, the recent leading cases in and out of the country show that the principle of strict compliance is being weakened. The leading cases in America show two trends of weakening the principle of strict compliance. That is, on the contrary to strict compliance, tends to apply substantial compliance (which puts more value on the substance of the documents). These leading cases reflect the attitudes of the judicial and the legislative authorization that don't want to approve formal approach to the commercial law. Recently, the Supreme Court of Korea is giving a decision on the principle of strict compliance, "The documents attached to an L/C should strictly comply with the conditions in the L/C, but it doesn't mean that they should be perfectly identical without any mistake in words. In case the bank can understand through reasonable care that a small mistake in words is too trivial to give different meaning or to give damage to the conditions of the L/C, the documents are regarded to comply with the conditions of the L/C. However, the judgment should be based on whether the difference between the documents and the L/C can be admitted by the international standard bank transaction practice or not." This decision tells that the principle of strict compliance is quite much modified so application of this modification can't be ignored. However, from the viewpoint of the party who requests to open an L/C, there is a criticism that a bank's arbitrary judgement can be involved. Therefore, reviewing the original purpose of L/C transactions (activating international transactions), the principle of strict compliance may be thought old-fashioned because it emphasizes a form, but in reality, for prompt transaction and payment, the principle of strict compliance should be observed in L/C transactions. And further, if a legislative device is prepared to systematically compensate for several side-effects, the principle of strict compliance will improve dynamic flow of prompt and low-costly L/C transactions. On the other hand, it will be able to protect the interested parties.

• The Journal of Korean Society for School & Community Health Education
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• v.1 no.2
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• pp.105-125
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• 2000

The purpose of this study was to examine the influence of school safety accident on teacher's normal educational activities and to seek some desirable ways to cope with it. The subjects in this study were 351 class teachers randomly selected from Seoul and Kyonggi Province and surveyed from April through July, 2000. The conclusions were as follows; 1. Actual Condition of School Safety Accident 1) Approximately many teachers investigated had had an experience to suffer safety accident. Safety accident occurred most during break or class, but there was a significant difference according to service area. 2) Safety accident took place most in playground, and the most common cause was student's own carelessness, and the most widely occurred accident type was an injury. But there was no significant difference caused by the general characteristics of the teachers. 2. Influence of Safety Accident On Teacher's Educational Activities. 1) The largest reason they offered safety education was to ensure student safety. The greatest number of them had an opinion they would consider changing or giving up a planned normal educational activity if they recognized any possibilities of safety accident. There was a significant difference in this point according to gender and career. 2) They worried about possible safety accident most during field study, but there was a significant difference according to gender or presence or absence of safety accident experience. 3) The general characteristics of teacher produced a significant difference to an experience of avoiding educational activity due to psychological withdrawal, but safety accident experience didn't make any difference. 3. Minimization of Teacher Damage or Loss from Safety Accident. 1) The dominant opinion about teacher's small mistake for any occurrence of safety accident was that the responsibility should be escaped to maintain teacher's authority. For severe mistake, however, there were two different opinions at the same percentage: one was being exempted and the other was taking civil liability. 2) Establishing teacher insurance was preferred as a way to minimize teacher's economic loss from safety accident, but there was a significant difference according to gender. 3) The dominant opinion about the payment of insurance premium for safety accident was that it should be paid from school operating expenses.