• Restorative Dentistry and Endodontics
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• v.44 no.1
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• pp.2.1-2.6
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• 2019

Objectives: The purpose of this research was to identify the top 10 most-cited articles on the management of fractured or broken instruments and to perform a bibliometric analysis thereof. Materials and Methods: Published articles related to fractured instruments were screened from online databases, such as Web of Science, Scopus, PubMed, and ScienceDirect, and highly cited papers, with at least 50 citations since publication, were identified. The most-cited articles were selected and analysed with regard to publication title, authorship, the journal of publication, year, institution, country of origin, article type, and number of citations. Results: The top 10 most-cited articles were from various journals. Most were published in the Journal of Endodontics, followed by the International Endodontic Journal, and Dental Traumatology. The leading countries were Australia, Israel, Switzerland, the USA, and Germany, and the leading institution was the University of Melbourne. The majority of articles among the top 10 articles were clinical research studies (n = 8), followed by a basic research article and a non-systematic review article. Conclusions: This bibliometric analysis revealed interesting information about scientific progress in endodontics regarding fractured instruments. Overall, clinical research studies and basic research articles published in high-impact endodontic journals had the highest citation rates.

• Asia-Pacific Journal of Business
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• v.11 no.1
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• pp.61-75
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• 2020

Purpose - The purpose of this study was to examine the efficiency of the foreign exchange markets in Korea, Japan and China. Design/methodology/approach - This study collected 1327 observations each of the daily closing exchange rates of the three currencies against the US dollar for the sample period from January 1, 2015 to January 31, 2020, based on the tests for autocorrelation, unit root tests and GARCH-M(1,1) model estimation. Findings - We have found that the autocorrelation test indicates the lack of autocorrelation and unit root test confirms the existence of unit roots in all times series of the three currencies, respectively. The GARCH-M(1,1) test results, however, suggest that the exchange rates do not follow a random walk process. In conclusion, the recent spot foreign exchange markets in Korea, Japan and China are believed to be informationally inefficient. Research implications or Originality - These findings have practical implications for both individual and institutional investors to be able to obtain excess returns on their investments in the foreign exchange markets in three countries by using appropriate risk management, portfolio strategy, technical analysis, etc. This study provides the first empirical examination on the foreign exchange market efficiency in the three biggest economies in Asia including China, which has been excluded from research due to its exchange rate regime.

• International Journal of Advanced Culture Technology
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• v.11 no.3
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• pp.310-314
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• 2023

The purpose of this study is to predict the remaining capacity of lithium-ion batteries and evaluate their performance using five artificial intelligence models, including linear regression analysis, decision tree, random forest, neural network, and ensemble model. We is in the study, measured Excel data from the CS2 lithium-ion battery was used, and the prediction accuracy of the model was measured using evaluation indicators such as mean square error, mean absolute error, coefficient of determination, and root mean square error. As a result of this study, the Root Mean Square Error(RMSE) of the linear regression model was 0.045, the decision tree model was 0.038, the random forest model was 0.034, the neural network model was 0.032, and the ensemble model was 0.030. The ensemble model had the best prediction performance, with the neural network model taking second place. The decision tree model and random forest model also performed quite well, and the linear regression model showed poor prediction performance compared to other models. Therefore, through this study, ensemble models and neural network models are most suitable for predicting the remaining capacity of lithium-ion batteries, and decision tree and random forest models also showed good performance. Linear regression models showed relatively poor predictive performance. Therefore, it was concluded that it is appropriate to prioritize ensemble models and neural network models in order to improve the efficiency of battery management and energy systems.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.113-119
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• 2014

To examine the soil reinforcement by the shrub with shallow root systems for slope stability, we developed insitu apparatus for direct shear test and conducted the insitu field tests for Lespedeza cyrtobotrya, a representative revegetation species for artificial hillslopes. The insitu field tests were conducted for two different soil conditions (the rooted soils and non-rooted soils) and we then compared the experimental values with those calculated from the Wu model. The results showed that the soil reinforcement derived from the insitu field tests ranged from 0.01525 to 0.1438 $kgf/cm^2$ while the one calculated from the Wu model ranged from 0.1952 to 0.2696 $kgf/cm^2$. Our finding suggests more field tests are needed to collect the related parameters in the model application thereby predicting the reliable soil reinforcement by the shrub root systems.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.04a
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• pp.13-17
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• 2007

The green roof industry have been developed with Europe, North America, Japan. At the same time, being recognized the important of green roofs in domestic industry and we just start to develop the relative technology as analyzing the future direction of advanced technology. Recently, local self-government including Seoul support the system for green roof which provide 50% of working expenses form of Matching Fund by Seed Money. As years go by, the number of build up the green roof has gradually increased to be proved. At this result caused by management of system in government, unstructured construction system, low development of support technology. In this study as analyzing the present of technical development, supporting by law and system for the advanced waterproofing and root penetration resistance technology, we suggest the development direction of it to be compared with application advanced technology and we could strengthen the international competitiveness to be industrialized the green roof considering system, technology, human infrastructure.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.4
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• pp.324-328
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• 2014

Aberrant anatomy of mandibular premolars is very rare in Korean, but aberration can contribute the endodontic failure as it makes difficult to remove the irritants during cleaning and shaping procedure. This case report describes the successful root canal treatment of a rare mandibular first premolar with C-shaped root canal as using a cone-beam computed tomography to understand the internal shape of root canal system and a dental operating microscope to improve the magnification and illumination.

• Journal of the Korean Wood Science and Technology
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• v.52 no.1
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• pp.31-46
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• 2024

Subterranean termite attacks on cajuput (Melaleuca cajuputi) seedling roots were widespread in several of Java's Perum Perhutani Forest Management Units. This attack was suspected to be related to the chemical components of the cajunput seedling roots. This study was conducted to determine the bioactivity of cajuput seedling root extract as an attractant for the subterranean termite Coptotermes curvignathus Holmgren (Isoptera: Rhinotermitidae). The extraction process was performed according to ASTM D1108-96, and the extract was characterized using gas chromatography-mass spectrometry (GC-MS). Bioactivity testing of the extracts was carried out using attractiveness and no-choice feeding bioassays. The results showed that the average root extraction yield from cajunput seedlings was 4.94%. The attractiveness of the extract solutions at concentrations of 0.50%, 0.75%, and 1.00% were 45.33%, 62.00%, and 74.67%, respectively. The mortality rate of C. curvignathus termites ranged from 9.63% to 24.44%. Cajuput seedling root extract's lethal concentration 50 was 2.45% (non-toxic). GC-MS analysis showed that the extract contained linoleic acid, which has the potential to attract insects.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.783-789
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• 2010

The effective method for heating root-zone during winter season was studied in the aspects of growth, yield and economics for tomato ($Solanum$ $lycopersicum$) in perlite bag culture. There were four root-zone heating treatments: two hours heating from one hour before to one hour after sunrise, four hours from two hours before to two hours after sunrise, 15 hours after sunset, and no heating. The growth characteristics of the upper parts of plants were not significantly different among the treatments, but root volume increased with longer heating of the root zone. The Plant Development Index, using stem diameter and the length between growing tip and the upper flowering truss, showed relation between yield per cluster and growth pattern. The treatment heating for four hours was the most economic in terms of growth and yield of tomato.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.254-257
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• 2003

It is common to experience delays during construction projects. Delays can ca use substantial damages to an owner as well as contractors and is the sources of frequent disputes and claims. Many studies have been carried out to assess the causes of delays in construction projects. They are found to be almost similar, except some prevailed local condition. Most of the common construction delay factors are attributed to design faults, incompetent contractor, lack of team accountability etc. To minimize or eliminate the delay we have to follow the recognized fundamental principles of management such as: cost-time relationship, time priority, accountability, rewards, innovative thinking etc. The root causes of delays found out in this paper are not so much different than other previous study. If the implementing agencies properly followed the, fundamental management principles and some other related corrections as recommended in the paper, much construction delays can be avoided.

• Journal of Korean Society for Quality Management
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• v.33 no.3
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• pp.91-104
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• 2005

Tolerance analysis plays an important role in design and manufacturing stages for reducing manufacturing cost by improving producibility. In most production processes encountered in practice, a process mean may shift or drift in the long run although process is in control. This study discusses the feasibility of three most common inflation factors(Bender, Gilson and Six Sigma) as a correction to Root Sum of Squares(RSS) method to compensate heuristically for a shift of process mean and nonnormal component distributions from simulation experiments and proposes the guidelines for choosing the inflation factor.