• International Journal of Control, Automation, and Systems
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• v.6 no.4
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• pp.534-543
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• 2008

To use the Global Positioning System (GPS) carrier phase measurement for precise positioning, the integer ambiguities at the early stage of most algorithms must be determined. Furthermore, if a precise positioning is to be applied to real time navigation, fast determination and validation methods for integer ambiguity are essential. In this paper, the Wald test that simultaneously determines and validates integer ambiguities is used with assistance of the Inertial Navigation System (INS) to improve its performance. As the Wald test proceeds, it assigns a higher probability to the candidate that is considered to be true at each time step. The INS information is added during the Wald test process. Large performance improvements were achieved in convergence time as well as in requiring fewer observable GPS satellites. To test the performance improvement of the Wald test with the INS information, experimental tests were conducted using a ground vehicle. The vehicle moved in a prescribed trajectory and observed seven GPS satellites. To verify the effect of the INS information on the Wald test, the convergence times were compared with cases that considered the INS information and cases that did not consider the INS information. The results show that the benefits of using the INS were emphasized as fewer GPS satellites were observable. The performance improvement obtained by the proposed algorithm was shown through the fast convergence to the true hypothesis when using the INS measurements.

• The korean journal of orthodontics
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• v.39 no.3
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• pp.177-184
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• 2009

Objective: The aim of this study was to investigate the occurrence rate of bacteremia following toothbrushing with toothpastes composed of several antibacterial agents and compare the results with the conventional oral hygiene maintaining methods in orthodontic patients. Methods: This clinical study included 100 adult orthodontic patients who were divided into 4 groups. Each group comprised of 25 patients, wearing fixed orthodontic appliances. In the first group, bacteremia was assessed after toothbrushing without using any toothpaste. In the second group, a 0.2% chlorhexidine gluconate mouthrinse was used before brushing with no toothpaste. In the third group, subjects brushed with a commonly used toothpaste which did not include an additional antimicrobial agent. The fourth experimental group used toothpaste which included tea tree oil, clove oil, peppermint oil and bisabolol as antimicrobial elements. Pre- and post-brushing blood samples were obtained using a strict aseptic technique. All samples were microbiologically evaluated using blood culture bottles. Results: Toothbrushing in orthodontic patients yielded to an increase in the occurrence rate of bacteremia when using normal toothpaste or no toothpaste at all. Conclusions: The use of chlorhexidine mouthwash before toothbrushing, and brushing with antimicrobial toothpaste did not show a statistically significant difference in preventing the occurrence of bacteremia (p > 0.05).

• Journal of the Korean Geographical Society
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• v.47 no.1
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• pp.121-139
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• 2012

The purpose of this study is to derive the implications for improving 'the Geography of Korea' by analyzing the regional geographies of other countries. For this purpose, the regional geographies of eight countries are used: the United Kingdom, France, and Germany in Europe, the United States in America, Japan and China in Asia, and Turkey and Pakistan in Arab. After we select the representative regional geography for each country, its general characteristics, structure, style, and contents are analyzed. Based on the findings, implications for improving 'the Geography of Korea' are summarized in terms of the contents, style, and publication project. These implications suggest that 'the Geography of Korea' needs to be improved by explaining the regional identity in a more refined way and by attracting more readers.

• Structural Engineering and Mechanics
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• v.36 no.6
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• pp.759-783
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• 2010

In this paper, compressive strength of carbon fiber reinforced polymer (CFRP) confined concrete cylinders is formulated using a hybrid method coupling genetic programming (GP) and simulated annealing (SA), called GP/SA, and a robust variant of GP, namely multi expression programming (MEP). Straightforward GP/SA and MEP-based prediction equations are derived for the compressive strength of CFRP-wrapped concrete cylinders. The models are constructed using two sets of predictor variables. The first set comprises diameter of concrete cylinder, unconfined concrete strength, tensile strength of CFRP laminate, and total thickness of CFRP layer. The most widely used parameters of unconfined concrete strength and ultimate confinement pressure are included in the second set. The models are developed based on the experimental results obtained from the literature. To verify the applicability of the proposed models, they are employed to estimate the compressive strength of parts of test results that were not included in the modeling process. A sensitivity analysis is carried out to determine the contributions of the parameters affecting the compressive strength. For more verification, a parametric study is carried out and the trends of the results are confirmed via some previous studies. The GP/SA and MEP models are able to predict the ultimate compressive strength with an acceptable level of accuracy. The proposed models perform superior than several CFRP confinement models found in the literature. The derived models are particularly valuable for pre-design purposes.

• Journal for History of Mathematics
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• v.18 no.1
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• pp.33-48
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• 2005

The Rule of False Position is known as an arithmetical solution of algebraical equations. On the other hand, the Excess-Deficit Rule is an algorithm for calculating about excessive or deficient quantitative relations, which is found in the ancient eastern mathematical books, including the nine chapters on the mathematical arts. It is usually said that the origin of the Rule of False Position is the Excess-Deficit Rule in ancient Chinese mathematics. In relation to these facts, we pose two questions: - As many authors explain, the excess-deficit rule is a solution of simultaneous linear equations？ - Which relation is there between the two rules explicitly？ To answer these Questions, we consider the Rule of Single/Double False Position and research the Excess-Deficit Rule in some ancient mathematical books of Chosun Dynasty that was heavily affected by Chinese mathematics. And we pursue their historical traces in Egypt, Arab and Europe. As a result, we can make sure of the status of the Excess-Deficit Rule differing from the Rectangular Arrays(the solution of simultaneous linear equations) and identify the relation of the two rules: the application of the Excess-Deficit Rule including supposition in ancient Chinese mathematics corresponds to the Rule of Double False Position in western mathematics. In addition, we try to appreciate didactical value of the Rule of False Position which is apt to be considered as a historical by-product.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.18 no.1
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• pp.1-9
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• 2015

Eating behaviour disorder during early childhood is a common pediatric problem. Many terminologies have been used interchangeably to describe this condition, hindering implementation of therapy and confusing a common problem. The definition suggests an eating behaviour which has consequences for family harmony and growth. The recent Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition does not cover the entire spectrum seen by pediatricians. Publications are substantive but level of evidence is most of the time low. This purpose of this review is to clarify terminology of eating behaviour problems during early childhood; including benign picky eating, limited diets, sensory food aversion, selective eating, food avoidance emotional disorder, pervasive refusal syndrome, tactile defensiveness, functional dysphagia, neophobia and toddler anorexia. This tool is proposed only to ease the clinical management for child care providers. Diagnostic criteria are set and management tools are suggested. The role of dietary counselling and, where necessary, behavioural therapy is clarified. It is hoped that the condition will make its way into mainstream pediatrics to allow these children, and their families, to receive the help they deserve.

• Pediatric Infection and Vaccine
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• v.22 no.3
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• pp.131-135
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• 2015

Since April 2012, more than 1,600 laboratory-confirmed human infections with Middle East Respiratory Syndrome Coronavirus (MERS-CoV) have been reported, occurring primarily in countries in the Arabian Peninsula; the majority in Saudi Arabia. The MERS outbreak in Korea, which began in May 2015 through the importation of a single case who had recently traveled to Bahrain, the United Arab Emirates, Saudi Arabia, and Qatar. As of November 28th, 186 secondary and tertiary cases had been reported; 38 deaths, mainly associated with underlying chronic illnesses, were reported. One case was exported to China and has been recorded as the first MERS case in China. Thirty-seven confirmed cases were associated with the index case, who was hospitalized from May 15 to May 17. Emergency room at one of the nation's largest hospitals had been affected by hospital-to-hospital and intra-hospital transmissions of MERS-CoV, resulting in an outbreak of 90 infected patients. The vast majority of 186 confirmed cases are linked to a single transmission chain associated with health facilities. The median age of patients is 55 years, with a range of 16 to 87 years. The majority (61%) of patients are men. Twenty-five (14%) of the cases involve healthcare workers. The overall median incubation period was six days, but it was four days for secondary cases and six days for tertiary cases. There has been no evidence of airborne transmission and sustained human-to-human transmission in communities. Intensified public health measures, including contact tracing, quarantine and isolation of all contacts and suspected cases, and infection prevention and control have brought the MERS-CoV under control in Korea. Since 4 July no new cases have been reported.

• The Korean Journal of Health Service Management
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• v.5 no.2
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• pp.209-226
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• 2011

The purpose of this study is to analyze and find out key success factors and marketing strategies of Bumrungrad Hospital in Bangkok, Thailand. The major success factors of Bumrungrad Hospital are as follows; First, Bumrungrad Hospital had professional medical team and board of directors who had the international career. Second, Bumrungrad was supported by Thai government and they were in a cooperative relationship with each other for the development of the medical industry. Third, Bumrungrad appropriately handled the internal and external changes including Asia Financial Crises in 1997 and others. Fourth, Bumrungrad diversified and broaden its business field such as global medical investing and management, medical technology, anti-age medicine and wellness. Marketing strategies of Bumrungrad analyzed are the following four factors. First, Bumrungrad focused on the quality of services by employing professional medical staffs, who have the international certification, and by constructing IT system for hospital management. Second, Bumrungrad has maintained an equalized price policy to attract the customers bothin the domestic and foreign markets. The cost for care has appealed the foreign customers for its comparatively low price, but it focused mainly on the upper middle class in Thailand. Third, it established, managed, and consulted hospitals in the foreign countries including the Philippines and the Arab Emirates. Fourth, it adopted differentiated promotion strategies suitable for the special needs of domestic and foreign customers, and put emphasis on the buzz marketing.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.1
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• pp.29-33
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• 2019

Objectives: Bone density seems to be an important factor affecting implant stability. The relationship between bone density and primary and secondary stability remains under debate. The aim of this study was to compare primary and secondary stability measured by resonance frequency analysis (RFA) between different bone types and to compare implant stability at different time points during 3 months of follow-up. Materials and Methods: Our study included 65 implants (BioHorizons Implant Systems) with 3.8 or 4.6 mm diameter and 9 or 10.5 mm length in 59 patients. Bone quality was assessed by Lekholm-Zarb classification. After implant insertion, stability was measured by an Osstell device using RFA at three follow-up visits (immediately, 1 month, and 3 months after implant insertion). ANOVA test was used to compare primary and secondary stability between different bone types and between the three time points for each density type. Results: There were 9 patients in type I, 18 patients in type II, 20 patients in type III, and 12 patients in type IV. Three implants failed, 1 in type I and 2 in type IV. Stability values decreased in the first month but increased during the following two months in all bone types. Statistical analysis showed no significant difference between RFA values of different bone types at each follow-up or between stability values of each bone type at different time points. Conclusion: According to our results, implant stability was not affected by bone density. It is difficult to reach a certain conclusion about the effect of bone density on implant stability as stability is affected by numerous factors.

• International journal of steel structures
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• v.18 no.5
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• pp.1639-1653
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• 2018

Bolted connections are suitable due to high quality prefabrication in the factory and erection in the workplace. Prefabrication and modularization cause high speed of erection and fabrication, high quality and quick return of investment. Their technical hitches transportation can be removed by prefabrication of joints and small fabrication of components. Box-columns are suitable members for bolted structures such as welded steel structures with moment frames in two directions etc., but their continual fabrication in multi-story buildings and performing the internal continuity plate in them will cause some practical dilemmas. The details of the proposal technique introduced here, is to remove such problems from the box columns. Besides, some other advantages include new prefabricated bolted beam-to-column connections referred to BBCC. This connection is a set of plates joined to columns, beams, support, and bolts. For a better understanding of its fabrication and erection techniques, two connection and one structural maquettes are made. The present work aims to study the cyclic behavior of connection numerically. To verify the accuracy of model, a similar tested connection was modelled. Its verification was then made through comparison with test results. The behavior of connection was evaluated for an exterior connection using three different support shapes. The effects of support shapes on rigidity, ductility, rotation capacity, maximum strength, four rad rotation strength were compared to those of the AISC seismic provision requirements. It was found that single beams support has all the AISC seismic provision requirements for special moment frames with and without a continuity plate, and box with continuity plate is the best support in the BBCC connection.