• The Journal of Advanced Prosthodontics
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• v.11 no.4
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• pp.215-222
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• 2019

PURPOSE. To evaluate the polishing effect on roughness and color change of pressed and layering ceramics after immersion in coffee solution. MATERIALS AND METHODS. 88 ceramic discs ($1.0mm{\times}10.0mm$) were manufactured - 44 nano-fluorapatite layering ceramics (IPS e.max Ceram. Group C) and 44 pressed lithium disilicate ceramic discs (IPS e. max Press - Group P). Each group was divided into 4 subgroups according to surface treatments: (G) Glaze, (S) Shofu polishing system (Shofu Inc.), (E) Edenta AG polishing System, (KG) $30-{\mu}m$ diamond granulation tip. Surface roughness (Ra) and color change (${\Delta}E$) measurings after the surface treatments were performed, before and 12 days after the immersion in coffee solution. A samples' qualitative analysis was conducted with a scanning electron microscopy (SEM). Data were statistically-treated with one-way-ANOVA and Duncan's tests, apart from paired t-test and Pearson's correlation test (${\alpha}=5%$). RESULTS. The decrescent order, both for surface roughness (Ra) and ${\Delta}E$ for both ceramics were: KG > E > S > G (P<.05). With exception for PG and CG subgroups, which did not present statistical difference between them, all other pressed ceramics subgroups presented smaller Ra values and greater ${\Delta}E$ values than the layering ceramics subgroups (P<.05). CONCLUSION. Although mechanical polishing systems presented intermediate Ra values, their colors were considered clinically acceptable. There is a strong correlation between the surface roughness and the color change of tested ceramics.

• Restorative Dentistry and Endodontics
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• v.21 no.2
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• pp.569-584
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• 1996

The purpose of this study was to elucidate the effect of benzalkonium chloride on tensile bond strength of BPDM/HEMA dentin bonding. One hundred sixty dentin specimens from freshly extracted bovine mandibular incisors were used, and 0, 0.02, 0.1 or 0.5% benzalkonium chloride solution was applied to the dentin specimen with/after phosphoric acid. 32% phosphoric acid was used when the specimens were bonded with One-Step$^{TM}$, a BPDM/HEMA system and 10% was used when bonded with All-Bond$^{(R)}$ 2, a NTG-GMA/BPDM system. Aelitefil$^{TM}$ composite resin was bonded to the pretreated dentin specimen with the use of All-Bond$^{(R)}$ 2 or One-Step$^{TM}$ dentin bonding agent. After the bonded specimens were stored in $37^{\circ}C$ distilled water for 24 hours, tensile bond strength was measured. The fractured dentin specimens were examined under the scanning electron microscope. The results were as follows : Benzalkonium chloride application after acid-treatment resulted in decrease of dentin bond strength of One-Step$^{TM}$, a BPDM/HEMA system (p>0.05). Benzalkonium chloride application did not exert any influence on dentin bond strength of All-Bond$^{(R)}$ 2, a NTG-GMA/BPDM system (p>0.05). There was no relationship between the concentration or application method of benzalkonium chloride and the dentin bond strength of One-Step$^{TM}$ or All-Bon$^{(R)}$ 2 (p<0.05). On SEM examination of the fractured dentin-resin interface, while mixed failure was prominent in dentin bonding with One-Step$^{TM}$, adhesive and mixed failures were seen together in dentin bonding with All-Bond$^{(R)}$ 2 regardless of the concentration and application method of benzalkonium chloride.

• Smart Structures and Systems
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• v.15 no.3
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• pp.897-911
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• 2015

This study presents a novel approach based on advancements in Evolutionary Computation for data-driven modeling of complex multi-dimensional memory-dependent systems. The investigated example is a benchmark coupled three-dimensional system that incorporates 6 Bouc-Wen elements, and is subjected to external excitations at three points. The proposed technique of this research adapts Genetic Programming for discovering the optimum structure of the differential equation of an auxiliary variable associated with every specific degree-of-freedom of this system that integrates the imposed effect of vibrations at all other degrees-of-freedom. After the termination of the first phase of the optimization process, a system of differential equations is formed that represent the multi-dimensional hysteretic system. Then, the parameters of this system of differential equations are optimized in the second phase using Genetic Algorithms to yield accurate response estimates globally, because the separately obtained differential equations are coupled essentially, and their true performance can be assessed only when the entire system of coupled differential equations is solved. The resultant model after the second phase of optimization is a low-order low-complexity surrogate computational model that represents the investigated three-dimensional memory-dependent system. Hence, this research presents a promising data-driven modeling technique for obtaining optimized representative models for multi-dimensional hysteretic systems that yield reasonably accurate results, and can be generalized to many problems, in various fields, ranging from engineering to economics as well as biology.

• Journal of Korean Physical Therapy Science
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• v.18 no.4
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• pp.47-58
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• 2011

The purpose of this study was to analyses the main factors of research papers for related with home physical therapy. This study was retrospective descriptive study, the period of data collection was from 1991 to 2011. The data was collected by the journal related in physical therapy, the dissertation of academic degree, National Assembly Library and the web-site for academic information. In the web-site, searched with the keyword 'home physical therapy' and 'after school voucher'. The results were as follows; 1. In the home physical therapy, visiting physical therapy, school physical therapy, there were different based on laws; home physical therapy was based on medical law, visiting physical therapy was based on law for community health and law for long term health insurance, school physical therapy was based on special education law. 2. The summary of research title/thema from 1991 to 2011 was as follows; for the home and visiting physical therapy 'the needs and necessity of home and visiting physical therapy' was 18 papers, 'the contents of service of home and visiting physical therapy' was 18 papers, 'program and skill development' was 16 papers, 'system developing and induction strategy of home and visiting physical therapy 'was 15 papers, 'costs of nome and visiting physical therapy' was 2 papers, 'perception and information of home and visiting physical therapy' was 9 papers, 'Recoding system and administration management' was 9 papers, 'the others 'was 14 papers, for the school physical therapy 'after school voucher system' was 9 papers, the others was 4 papers. The total papers was 114 papers. 3. Finally suggested 'Model of Educational Program for HomeVisiting and School Physical Therapy'.

• The Journal of Internal Korean Medicine
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• v.22 no.4
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• pp.647-657
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• 2001

In the oriental medicine field, researches have been in progress regarding oriental medical factors. I also carried out a clinical study on stroke, from which I discovered meaningful results about important factors that impact on the prognosis of stroke. We studied 132 patients after diagnosis of stroke through a Brain-CT scan and MRI sea, to the oriental internal medicine department at the Hospital affiliated to Oriental Medical College, Dongeui University. All the patients showed meaningful improvement in the examination of their symptoms after four weeks, compared with the first week. Between strokes involving meridian system and strokes involving internal organs, the symptom of paralysis caused by strokes involving meridian system, which patients were in favorable initial condition, had improved significantly and that by strokes involving internal organs had not. The group whose initial bowel movement since the stroke was delayed, whose coating on the tongue was thick or the tongue was dry, whose pulse was tachycardiac, or who had a history of hypertension or diabetics showed a significantly worse symptom after 4 weeks than that of groups in the opposite cases.

• The Korean Journal of Health Service Management
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• v.10 no.1
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• pp.13-26
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• 2016

Objectives : The aim of this study was to investigate whether there is a difference in the factors affecting the financial performance and profitability before and after the specialty hospital designation and thereby identifying the differentiated significance of the financial performance of specialty hospitals. Methods : Based on the year 2011, the analysis period was divided into the pre-specialty hospital designation (2007-2010) and post-specialty hospital designation (2011-2014), and the data were pooled according to the respective analysis period and analyzed by descriptive statistics and regression analysis. Results : The difference in the financial factors that affected the financial performance and profitability before and after the specialty hospital designation was discovered, and a financial performance factor different from prior studies was found. Conclusions : This study identified improved outcomes in financial performance due to the specialty hospital designation and the factors that affect profitability in terms of the finance of specialty hospitals.

• Journal of Fisheries and Marine Sciences Education
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• v.23 no.2
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• pp.221-233
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• 2011

The purpose of this research was made to suggest the improvement for problems of indication subject of Fisheries & Maritime High School teacher's certificate issued by the operation of the 7th national curriculum in 2000. After analyzing the integrated indication subjects related with fisheries & Maritime high school, among the middle school teacher's 24 subjects of industrial world, the problems and improvements can be arranged as followed. Firstly, the subjects of fisheries & Maritime high school teacher's certificates are fishing industry, aquiculture, sailing, engine and freezing and new subjects are ocean shipping and ocean logistics. Because the teacher's certificate was changed to integrated indication subjects, there were problems of teacher cultivation, teacher hiring, etc. So, in the actual field of school, teacher cultivating university and related department are necessary to strengthen high-quality majoring education/subjects and practical education as well as need to establish teacher cultivating system by teacher cultivating organization's evaluation system and teacher cultivating education program related by differentiation and easiness of majoring characterization. Secondly, teacher cultivating for new departments and new subjects can apply related major system, free major system, etc. Thirdly, if professional high schools find majoring areas whose content is same one another and introduce common indication subject system, it will be helpful to improve the quality of teachers, teacher certification examination, etc. of professional area.

• Journal of the Korean Institute of Educational Facilities
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• v.27 no.1
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• pp.3-10
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• 2020

Due to the frequent occurrence of large-scale disasters such as recent earthquakes, the problem of the safety of old school buildings has emerged. The need to secure safety management technology through constant monitoring is increasing in an attempt to supplement old school buildings with weak disaster response capabilities. Traditional research is approaching the development of an existing sensor-based risk precursor information monitoring system. However, unlike this, in this study, we will focus on the development of a data analysis platform as part of the development of a continuous monitoring system that can be prepared for earthquakes, collapses, and fires, based on constantly measured data. For this reason, the development of a safety diagnostic algorithm based on the optimal sensor-attached points and sensor data reflecting the fragile characteristics of old school buildings was derived. Utilizing this, a message and action manual system for each management / use entity of school buildings after retirement was constructed.

• International Journal of Aerospace System Engineering
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• v.3 no.2
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• pp.22-25
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• 2016

This dissertation tried to analyze passenger behaviors after an accident with the possibilities of a variety of accidents open reflecting the phases of the times of increasing interests in safety of passengers as the use of means of transportation such as cars and airplanes is increasing. Because a lot of data on head-on collisions, broadside collisions and reverse side collisions have been gathered through lots of experiments and interpretations, I chose to study a relatively unfamiliar subject, dropping collision. For example, I tried to study passenger behaviors in seating position after a dropping collision in preparation for falling accidents due to recent frequently-occurring sinkholes, driver's carelessness or mechanical problems. I used MADYMO, passenger behavior interpretation program, and experimented with 2 meters high Drop Test device which I made in person to increase the reliability of the results. On the basis of these, I compared the real experiments with interpretations.

• The Journal of Sustainable Design and Educational Environment Research
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• v.13 no.2
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• pp.13-25
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• 2014

The recent trend has been consistently raised by the media of educational environment issues such as deteriorated existing school facilities, water-leaks due to the lack of proper maintenance and poor toilet facilities. For the efficient use of the budget to be used for maintenance of school facilities, an effort to extend the life of the facility to the max is needed. However, current maintenance system of school facilities is to deal with the defects after discovered, and consequently the durable period is shortened due to early deterioration of facilities and efficient budget execution cannot be realized. For this reason, the result emphasizes the need to improve maintenance management system of school facilities, and proposes a systematic bill of school facilities maintenance according to expert investigation and correlation analysis through school facilities maintenance-related information that is distributed to a number of laws.