• Journal of Educational Research in Mathematics
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• 제20권4호
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• pp.445-458
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• 2010

This study intends to investigate the process of the development of quantity concept and how to deal with the quantity calculus in elementary school, and to find out the implication for improving the curriculum and mathematics textbooks of Korea. There had been the binary Greek categories of discrete number and continuous magnitude in quantity concept, but by the Stevin's introduction of decimal, the unification of these notions became complete. As a result of analyzing of the curriculum and mathematics textbooks of Korea, there is a tendency to disregard the teaching of quantity and its calculus compared to the other countries. Especially multiplication and division of quantity is seldom treated in elementary mathematics textbooks. So these should be reconsidered in order to seek the direction for improvement of mathematic teaching. And Korea's textbooks need the emphasis on the quantity calculus and on constructing quantity concept.

• Fashion & Textile Research Journal
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• 제7권1호
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• pp.56-62
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• 2005

Fancy Yarn has developed diverse textures in fabrics, reducing the time in yarn and fabric production or apparel making in order to develop creative goods. In this study aimed to propose the use of a 4D box system to make fancy yarn shapes with loops, knops and spirals and the like. The change in texture was analysed and simulated to produce a suitable fabric image by using the fancy yarns fabric. The results are as follows. The plain weave, 2/2 basket weave, 2/2 twill weave, 2/2 2 complete broken weaves, and 5 harness sateen weaves were woven and a fabric image formed. In the case of the loop and the knop yarns fabric image, compared to the twisted fabric image the surface was covered by loops or some parts became partially black. In the case of the spiral shape it showed pattern continuity in spiral shapes 1, 2 and 3. The more twisted spirals produced a diamond shaped pattern or a twill line and a herring bone shaped twill line. An evenly distributed black fabric image appeared in 5 harness sateen weave. For the loop shape the broken weave or 5 harness sateen weave was produced; basket weave and broken weave for the knop yarn 1 or knop yarn 2; and for the spiral shape a plain fabric or 5 harness sateen weave were produced much similar to the fabric image. The surface texture of the mapped image compared to the twisted fabric image produces fancy yarn fabric images covered with loops or irregular spots caused by the knop and the spiral. Therefore it is appropriate or suitable for the simulation of tweed or woolen wool fabrics. The fabric image which produced consistent and continuous lines is therefore more suitable for simulations of twill or herringbone fabric images.

• Journal of Korean society of Dental Hygiene
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• 제14권6호
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• pp.789-794
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• 2014

The increasing cross-border mobility of dental school or dental hygiene students, educators, practitioners, programs and providers takes challenges for existing national quality assurance and accreditation frameworks and bodies, as well as for the systems for recognizing foreign qualifications. The new dental hygiene accreditation system was introduced to encourage the improvement of dental hygiene programs, to ensure the quality of education and, most of all, to establish an internationally compatible system of evaluation and accreditation. The accreditation procedure takes 1 year to complete. The result of the accreditation is released after evaluation via self-study report, site visit, preliminary draft report, responses from the institution and the results from the conciliation and review committees. The result from the accreditation procedure is either 'accreditation' or 'no accreditation'. Accredited schools receive one of several statuses following the evaluation. These are next general review, interim report and interim visit or suspension. Dental healthcare quality is not improved instantaneously, but instead gradually through continuous communication within the dental field. For this accreditation system to be successful, the following are essential: the accreditation agency should adopt hygiene education accreditation; it needs to become financially independent and managed efficiently; the autonomy and regulations surrounding the system need to be balanced; the professionalism of the system is ensured; and the dental field which includes not only dental program, but also hygiene program, needs to play an active role in the operation of the system.

• Restorative Dentistry and Endodontics
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• 제22권1호
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• pp.193-208
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• 1997

Much evidence now exists from both in vivo and in vitro studies to support the claim that small caries lesions can 'heal'. But, there are still different views on the mechanism of remineralization. So in order to find the best condition for the remineralization of incipient dental caries in maximum efficient way, the author conducted the experiment which reveals the effect of pH on remineralization. 40 specimens of sound permanent teeth without demineralization or crack, $100{\mu}m$ in thickness, were immersed in lactic acid buffered demineralization solution for 4 days. Dental caries with surface zone and subsurface lesion were artificially produced. All specimens were immersed in lactic acid buffered remineralization solution of pH 4.0, 4.5, 5.0, 5.5 containg fluoride ion for 10 days. The results were obtaind by observing the specimens for every 10 days under polarized microscopy at x25. 1. Remineralization did not occur in entire depth of body of lesion at given degree of saturation and concentration of fluoride ion. 2. The pattern of remineralization has increased according to increase of pH. So it can be concluded that supersaturated solution with fluoride ion can be affected by pH in remineralization of enamel, and pH 5.5 seems to be very effective in remineralization of deep and surface zone of dental caries. However, more complex factors exist in achieving complete remineralization and further continuous researches are needed to clarify the factors.

• Applied Chemistry for Engineering
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• 제7권3호
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• pp.443-452
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• 1996

Fouling is caused by sedimentation and corrosion of polymer, heavy paraffine, chemicals, heavy organics, asphaltene, etc. in the entire chemical process of heat exchanger, boiler, desalter, etc. Fouling phenomena remains a serious operating problem which results in increased energy consumption, increased pressure drops, reduction or complete loss of products yield, and increased maintenance costs. In order to calculate the separated amounts of foulants and to control the fouling process, the predictive model is developed which is based on Scott & Magat polymer solution theory, Peng-Robinson EOS, BWR EOS, and continuous and multicomponent thermodynamics.

• KIISE Transactions on Computing Practices
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• 제21권1호
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• pp.94-99
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• 2015

With the recent machine learning paradigm of using nonparametric Bayesian statistics and statistical inference based on random sampling, the Dirichlet distribution finds many uses in a variety of graphical models. It is a multivariate generalization of the gamma distribution and is defined on a continuous (K-1)-simplex. This paper presents a sampling method for a Dirichlet distribution for the problem of dividing an integer X into a sequence of K integers which sum to X. The target samples in our problem are all positive integer vectors when multiplied by a given X. They must be sampled from the correspondingly gridded simplex. In this paper we develop a Markov Chain Monte Carlo (MCMC) proposal distribution for the neighborhood grid points on the simplex and then present the complete algorithm based on the Metropolis-Hastings algorithm. The proposed algorithm can be used for the Markov model, HMM, and Semi-Markov model for accurate state-duration modeling. It can also be used for the Gamma-Dirichlet HMM to model q the global-local duration distributions.

• The Journal of the Korea Contents Association
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• 제16권12호
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• pp.203-212
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• 2016

The purpose of this study was to determine the effects of simulation practice education applying problem-based learning on problem-solving ability, critical thinking disposition, and learning satisfaction of nursing students. 63 nursing students taking the practice subject for integrated simulation at U University in K region were asked to complete a self-administered questionnaire to collect data before and after the simulation practice. The simulation practice education applying problem-based learning was effective in improving problem-solving ability and learning satisfaction significantly and positive correlation was found among problem-solving ability, critical thinking disposition, and learning satisfaction; that is, the better problem-solving ability, the higher level of critical thinking disposition and learning satisfaction. While the results of this study conducted in nursing students at a single university cannot be generalized, it was confirmed that simulation practice education applying problem-based learning was an effective teaching method in improving problem-solving ability and learning satisfaction of nursing students. It is therefore necessary to give simulation practice education applying problem-based learning on a systematic and continuous basis with the objective of improving problem-solving ability and learning satisfaction and promoting critical thinking disposition.

• Restorative Dentistry and Endodontics
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• 제26권4호
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• pp.341-349
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• 2001

Dental caries is the most common oral disease. There are many factors contributing to its development, but complete understanding and prevention are not fully known. However, it is possible to remineralize the early enamel curious lesion by fluoride containing remineralization solution. Recently the pH-cycling model has been used to examine the effect of fluoride solution on remineralization of artificial caries in vitro as it can closely simulate the conditions encountered in vivo within a carefully controlled environment. The aim of this study was to evaluate the remineralizing effects of supersaturated buffer solutions under pH-cycling model. The specimen with 3mm-diameter was made using mature bovine incisors which has no caries and has sound enamel surface. Early curious lesions were produced by suspending each specimens into demineralization solution at pH 5.0 for 33 hours and the specimen whose surface hardness value ranged from 25 to 45 VHN were used. The pH cycling treatment regimen consisted of 5 min soaks of three treatment solutions four times per days for 15 days and the continuous cycling of demineralization and remineralization were carried out for 15 days. Following the pH-cycling treatment regimen, the specimens' surface microhardness were measured by the Vickers hardness test (VHN) and analyzed by ANOVA and Duncan's multiple-range test. 1. The surface microhardness value of supersaturated solution, Senstime, and Gagline groups were increased after pH cycling, and that of supersaturated solution was significantly Increased compared to saline group(P<0.05). 2. The surface remineralization effect of fluoride containing solutions was accelerated by saliva under pH-cycling mode 3. The pH cycling model was considered appropriate to mimic the intra-oral pH changes when evaluating demineralization and remineralization in vitro. Under the results of above study, salivary remineralization effect can be improved by fluoride containing remineralization solution. The pH-cycling model was considered appropriate to mimic the intra-oral pH changes when evaluating demineralization and remineralization in vitro.

• The Journal of the Korean dental association
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• 제53권1호
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• pp.47-56
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• 2015

Obstructive sleep apnea (OSA), most common respiratory disorder of sleep, is characterized by intermittent partial or complete occlusions of the upper airway due to loss of upper airway dilating muscle activity during sleep superimposed on a narrow upper airway. Termination of these events usually requires arousal from sleep and results in sleep fragmentation and hypoxemia, which leads to poor quality of sleep, excessive daytime sleepiness, reduced quality of life and numerous other serious health consequences Untreated OSAS can cause various problems such as hypertension, diabetes, stroke, cardiac disease, daytime sleepiness. Various treatments are available, including non-surgical treatment such as medication or modification of life style, surgical treatment, continuous positive airway pressure (CPAP) and oral appliance (OA). Oral appliance is known to be effective in mild to moderate OSA, also genioglossus muscle advancement (GA) or maxillomandibluar advancement (MMA) is a good option for OSA patients with muscular or skeletal problems. Although the prevalence of OSA is increasing, the proportion of the patient treated by dentist is still very law. Dentists need to understand the mechanism of OSA and develop abilities to treat OSA patients with dental problems. The purpose of this paper is to give a brief overview about OSA and the dentist's role in OSA patients.

• Korean Institute of Interior Design Journal
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• 제21권6호
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• pp.71-78
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• 2012

These days, design has been used a very useful means to achieve differentiated urban images and establish the identity of a city, and as an effort to specialize local industries through design, public design projects are competing one another. However, the projects have considerable negative effects because of diverse reasons such as unorganized procedures. For continuous and organized projects which meet demands of the interested persons of public design, reasonable design management should be introduced with a use of design as a strategic means of management Therefore, this study examined the concepts of design management and its meaning in space and analysed cases of implementing components for management of public design projects. It searched for the factors of design management indicating design-oriented management and presented a strategy model which complements design-oriented management. The results of the study are presented as follows: First, strategic implementing components needed for a space design management process were obtained. A design recognition process aimed at what space aims at and needed to identify active components such as physical and indigenous environment. A design inquiry process included problem solution considering characteristics of multi-dimensional space active components, design development considering behavioral functions of humans, checklists needed to complete design and necessary components to institutionalize design. For definition of project space, guideline projects of public design should be progressed in the same context as urban design, and developmental directions of public design needed design inquiry in terms of space to create various experiences in space.