• Elastomers and Composites
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• v.56 no.1
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• pp.32-42
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• 2021

The vulcanizate structure of silica-filled compounds is affected by the filler-rubber interaction (FRI) due to the silica-rubber coupling reaction and the chemical crosslink density (CCD) of the matrix rubber. In this study, the vulcanizate structure changes of silica-filled compounds according to the silane and sulfur variation were quantitatively analyzed using the Flory-Rehner and Kraus equations. In efficiency vulcanization (EV) conditions with low sulfur content, FRI increased when the bis-[3-(triethoxysilyl)propyl]tetrasulfide (TESPT) content increased, and the CCD clearly decreased. By contrast, in semi-EV conditions with high sulfur content, as TESPT content increased, the FRI increased the same way EV conditions, but the CCD was unchanged. Based on these results, it was confirmed that FRI of the silica-filled compounds increased as TESPT content increased, but CCD decreased or retained similar values according to the vulcanization system, indicating that the formation reaction of FRI was preferred over CCD.

• Korean Security Journal
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• no.55
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• pp.31-55
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• 2018

The purpose of this study is to analyze the precedence analysis of traffic safety facilities installation for traffic accidents. The main results were as follows. First, the precedence of the number of traffic safety signs installation for the number of traffic accident is follows. The number of traffic safety signs[total number] (time precedent 1), the number of traffic safety signs[attention] (time precedent 7), the number of traffic safety signs[regulation] (time precedent 7), the number of traffic safety signs[indication] (time precedent 4) precede the number of traffic accidents as negative(-) relationship. Second, the number of traffic signal equipments[pedestrian lamp] (time precedent 2) precedes the number of traffic accidents as negative(-) relationship. Third, the precedence of the increase/decrease rate of traffic safety facilities installation for the increase/decrease rate of traffic accident is follows. The increase/decrease rate of traffic safety signs[total number] (time precedent 1), the increase/decrease rate of traffic safety signs[attention] (time precedent 1), the increase/decrease rate of traffic safety signs[indication] (time precedent 1), the increase/decrease rate of traffic safety signs[auxiliary] (time precedent 1) precede the increase/decrease rate of traffic accidents as negative(-) relationship. Fourth, the increase/decrease rate of traffic signal equipments[pedestrian lamp] (time precedent 0) accompanies the increase/decrease rate of traffic accidents as positive (+) relationship.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.89-100
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• 2018

The precedent study stage of defense programs is a project stage that is conducted to support the determination of an efficient acquisition method of the weapon system determined by the requirement. In this study, the FTA/FMEA technique was used in the safety analysis process to identify elements to be conducted in the precedent study stage and a methodology for deriving the key review elements through conceptualization and tailoring was suggested. To supplement the key elements derived from the existing research, it is necessary to analyze various events that may arise from key elements. To accomplish this, the HAZOP technique for safety analysis in other industrial fields was used to supplement the results of kdy element derivation. We analyzed and modeled the execution procedure by establishing input/output information and association with the key elements of the precedent study stage derived by linking HAZOP/FTA/FMEA techniques. In addition, performance maturity was evaluated for performance of precedent study, and a risk-based response manual was generated based on inter-working information with key elements with low maturity. Based on the results of this study, it is possible to meet the performance, cost, and schedule of the project implementation through application of the key elements and procedures and the risk management response manual in the precedent study stage of the defense program.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.83-84
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• 2010

Precast beam column joints with thru-connectors are developed from precedent study. The seismic performance is evaluated by experimental method. The test results of the precedent study showed that failure modes for all specimens were a compression failure by characteristics of unbonded tendon. Thus, variable considered in the research program for a tensile failure include the use of dog-boned longitudinal steel and concrete confined with steel spirals. The analysis of structural characteristics and evaluation of seismic performance of specimens was conducted by the experimental way. Comparison of result with the test specimens indicates that seismic performance is higher than the precedent study due to concrete confinement effect from steel spirals.

• The Korean Society of Law and Medicine
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• v.8 no.2
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• pp.291-328
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• 2007

Under the present law, a medical corporation has the legalistic character of a noncommercial corporation and its commerciality is restricted by public service. In a recent precedent, however, a judgment has considered the service part in medical practice. The tendency of a precedent is that both commerciality of a medical institution and medical corporation are allowed to be pursued under fundamental order-observance. This change is found in china and india, which consider a medical service as national industry. In the case of ours, the now government demonstrate the industrialization or the market of medical service through promotion of commerciality of a medical corporation. This paper deal with the meaning of a medical corporation and the present condition of medical market under the present law and recommends a tendency of law policy through study of foreign's and our precedent for commerciality of medical advertisement and medical corporation.

• Journal of the Korea Safety Management & Science
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• v.12 no.3
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• pp.93-99
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• 2010

As more than 90% of global trade is carried by sea there is little doubt that the safety of the ports at which the world's trading fleet call is of critical concern. The concept of 'safe port' continues to be an area of critical concern for charterers and ship-owners. In light of increased global security and health risks the recognised principles are under security. This paper examines the nature of safe port, and analyses the precedent trend of safe port and its Implication

• International conference on construction engineering and project management
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• 2005.10a
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• pp.1112-1117
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• 2005

Construction cost index is generally used to estimate the new project cost based on past construction data and to adjust contract cost when the price change of various articles and items of expenditure composing the contract occurs. In Korea, it is mostly used for adjustment of construction contract cost due to fluctuation of prices. However index adjustment rate which is used for adjustment of construction contract cost had some problems in calculating cost index of each expenditure item that could not reflect properly the change of construction cost. For supplementing these problems, the research of developing construction cost index has been executed. Through the precedent research, these problems were partially resolved but still remain. Therefore this research proposes method of making cost index that utilizes representative items of labor, material, and equipment by analyzing bill of quantity of road construction, through analysis and comparison of precedent study. By using this method, it is expected to solve problems which were not reflected in precedent studies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.50-61
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• 2018

A precedent defense project study was carried out in the early stage of the project to support efficient determination of the acquisition method of the determined weapons system. A precedent study in the early stage of the project has been neglected, but lack of performance and increased costs are continuing problems. In a precedent study on a number of items within a limited time frame, expected risks during project implementation were not identified and reduced by failing to review the key review element in depth. Therefore, in this paper, we studied the application of the FTA/FMEA technique used in the system safety analysis process to identify key factors to be considered when carrying out the defense research project. The methodology for the development of the key review items was established through the improvement of the FTA/FMEA technique in order to meet specific conditions and given conditions. Based on the results of this study, we redefined core key factors in the precedent study stage, thereby eliminating unnecessary and anticipated risks that may arise in the future project management aspects of the defense project. It is anticipated that this will reduce costs and time in terms of the lifecycle of the weapon system and promote stable operation of the project through reduction of risk.

• The Korean Nurse
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• v.13 no.4 s.72
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• pp.9-11
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• 1974

• Journal of architectural history
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• v.20 no.2
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• pp.39-54
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• 2011

The Bunhuangsa stone pagoda, constructed in AD. 634, National Treasure no. 30, has been named as 'brick-copied pagoda' since the Japanese-ruling period by scholars. It is said that the Chinese brick pagoda was its precedent model, however the Bunhuangsa Pagoda is the oldest of all the Chinese-style brick pagodas except one, the Sungaksa Pagoda. The Chinese pagoda cannot have been a precedent model to copy due to its complex detail of wood vestige, as the Bunhuangsa pagoda is simple form without ornament. Domestic brick pagodas cannot have been a precedent model to copy as well, because all the domestic brick pagodas are younger than the Bunhuangsa Pagoda. Therefore, the terminology 'brick-copied pagoda' is a fallacy; it is rather that later brick pagoda copied the precedent the Bunhuangsa stone pagoda. The Bunhuangsa Pagoda is simply a piled-up pagoda of thick or thin, big or small slates of stone, facing only one smooth side and therefore needing nothing to relate to brick. The originality of the pagoda is more related to simple piled-up Indian stone stupa rather than Chinese brick pagoda. The roof form of its gradually stepped projection comes from the harmika of the summit of Indian stupa. Contrary to general history, old Silla Dynasty imported Buddhism directly from India by sea. From written national history and by temple foundation history, the Indian Buddhism evangelist possibly made influence to the erecting of temple and pagoda. The original wrong terminology has made a harmful effect gradually to the naming of mass-styled stone pagoda of only carved stepped-roof form after brick-copied pagoda. The false term 'brick-copied pagoda' should be discarded, which comes with superficial observation based on toadyism to China and colonialism to Japan. Instead of the fallacious term, this paper suggests multi-storied 'piled-up pagoda with slate stone.'