• Restorative Dentistry and Endodontics
• /
• v.37 no.4
• /
• pp.201-206
• /
• 2012

Objectives: The purpose was to investigate the preference and usage technique of NiTi rotary instruments and to retrieve data on the frequency of re-use and the estimated incidence of file separation in the clinical practice among general dentists. Materials and Methods: A survey was disseminated via e-mail and on-site to 673 general dentists. The correlation between the operator's experience or preferred technique and frequency of re-use or incidence of file fracture was assessed. Results: A total of 348 dentists (51.7%) responded. The most frequently used NiTi instruments was ProFile (39.8%) followed by ProTaper. The most preferred preparation technique was crown-down (44.6%). 54.3% of the respondents re-used NiTi files more than 10 times. There was a significant correlation between experience with NiTi files and the number of re-uses (p = 0.0025). 54.6% of the respondents estimated experiencing file separation less than 5 times per year. The frequency of separation was significantly correlated with the instrumentation technique (p = 0.0003). Conclusions: A large number of general dentists in Korea prefer to re-use NiTi rotary files. As their experience with NiTi files increased, the number of re-uses increased, while the frequency of breakage decreased. Operators who adopt the hybrid technique showed less tendency of separation even with the increased number of re-use.

• Journal of Engineering Education Research
• /
• v.19 no.3
• /
• pp.3-12
• /
• 2016

The purpose of this study was to examine the current states of role model and effects on the expertise development in engineers (i.e., undergraduate students and experts in the field of engineering). Based on the previous studies, role model was categorized into two domain, general role model and value sharing role model. A total of 257 participants (162 undergraduate students, 95 experts) answered survey questions about their role model (the number of their role model, the frequency of meeting with them, and the number of sharing value with them), major confidence, knowledge acquisition, and research performance. The results showed that engineers had 1 or 2 general role models and that the contents of role model were different between the two groups. The value-sharing role model significantly predicted major confidence and research performance in undergraduate students whereas the number of general role model was closely associated with major satisfaction in experts. These results suggest that it is important for engineering major students to have general role model and value-sharing role model in order to enhance expertise development. Establishing infrastructure for having and meeting with role models can facilitate the development of personal expertise in engineers.

• 대한공업교육학회지
• /
• v.30 no.2
• /
• pp.45-59
• /
• 2005

The purpose of this study is to develop and operate a curriculum which is able to connect a vocational high school to a general high school. That curriculum makes it possible to meet the necessity of accepting the learning rights for the students of a small scale school located in a rural community. And also, it is able to broaden the implementation of the elective-centered curriculum in the $7^{th}$ curriculum. So, We developed a connected curriculum model which fulfills to the utmost the requirement of a few students who want to go to a collage after finishing vocational high school and who want to get a job after finishing general high school in a electing their subjects and then operated it with student's moving to the connected schools on a Saturday. In this study, we got the results as follows: First, we prepared the curriculum environments which can accept the learning-demands of students in a small scale school located in a rural community. To do so, we publicized the curriculum of a vocational high school connected to that of a general high school, made questions, and organized the committee of students, parents and teachers and so on. Second, we organized and implemented the connected curriculum so that a small number of students could learn the subjects they demands. So, a small number of the vocational high school students could have learned the 'Math I' and 'English Conversation' which were not allowed in their school. And also, a small number of the general high school students who hope to have an occupation after graduation could have learned 'Web Design' subject. Third, we examined the problems and presented the solving methods according to organizing and implementing the connected curriculum. So we could have served as an aid on building up the foundation of the generation of the elective-centered curriculum.

• Journal of Korean Academy of Nursing Administration
• /
• v.6 no.1
• /
• pp.147-159
• /
• 2000

This paper studied the factors that influence on RN staffing level in the 43 Specialized general hospitals. Market structure was analysed using the monopsony model. The degree of competition was estimated by Herfindal Index and market was defined as Great medical zone. As the result of the estimation, in the more competitive hospital market hospitals employed the higher level of RN staffing, so monopsony model was supported. Hospitals with above 1001bed employed more RN than hospitals with below 700bed did. Hospital type, hospital union and the number of medical doctor did not affect the level of RN staffing. There was positive correlation between the level of RN staffing and the number of nurse's aid. The structure of RN market in Specified general hospitals was proved monopsony market, it seems that government regulation will be needed to improve social efficiency and equity.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.18 no.4
• /
• pp.317-335
• /
• 2014

In this work, we investigate the global stability analysis of a viral infection model with antibody immune response. The incidence rate is given by a general function of the populations of the uninfected target cells, infected cells and free viruses. The model has been incorporated with two types of intracellular distributed time delays to describe the time required for viral contacting an uninfected cell and releasing new infectious viruses. We have established a set of conditions on the general incidence rate function and determined two threshold parameters $R_0$ (the basic infection reproduction number) and $R_1$ (the antibody immune response activation number) which are sufficient to determine the global dynamics of the model. The global asymptotic stability of the equilibria of the model has been proven by using Lyapunov theory and applying LaSalle's invariance principle.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.19 no.4
• /
• pp.443-457
• /
• 2015

We consider the M/M/c/c queues in which the customers blocked to enter the service facility retry after a random amount of time and some of idle servers can leave the vacation. The vacation time and retrial time are assumed to be of phase type distribution. Approximation formulae for the distribution of the number of customers in service facility and the mean number of customers in orbit are presented. We provide an approximation for M/M/c/c queue with general retrial time and general vacation time by approximating the general distribution with phase type distribution. Some numerical results are presented.

• The Journal of Korea Assosiation for Disability and Oral Health
• /
• v.3 no.1
• /
• pp.11-16
• /
• 2007

The use of general anesthesia as a special method of behavior management is necessary if certain handicapped or disabled child patient to receive dental treatment. This study was designed to report the results of 53 cases of complete oral rehabilitation under general anesthesia. The data were obtained from patients who were provided with dental treatment under general anesthesia for last 3years managed at the Dept. of pediatric dentistry in PNU Hospital. The distribution of age, gender, primary reason for general anesthesia, duration of dental procedure, number of treated tooth and periodic recall check-up were surveyed. In distribution of age, most(78%) were younger than 10 years and mean was 13.0 years. The reasons for providing general anesthesia were lack of cooperation due to various mental and physical handicapped situation(74%), congenital heart disease(13%), combined with medically compromised and behavior problem and others. The average duration of the treatments was 2 hours and 41 minutes and average duration of the anesthesia was 3 hours and 6minutes. The mean number of treated with restoration a children were 16.7 teeth. From the results, total dental rehabilitation under general anesthesia is a favorable modality to improve for disabled children's oral condition.

• The Journal of Korean Medicine
• /
• v.22 no.3
• /
• pp.51-62
• /
• 2001

Objectives : In Oriental Medicine, the improvement of constipation is very important for patients at the acute stage of cerebrovascular accident. For constipation, oral medicine has usually been used but is not available to stroke patients with dysphagia and mental disorder, and may bring about side effects on the gastrointestinal tract. In such cases, general enema has been used for assistant therapy, We needed to develop a more effective enema technique on constipation of stroke patients. Methods : Sixty-three patients were researched. We treated 29 patients with Bo-Ryu enema and 34 patients with general enema. To compare the effect of the Bo-Ryu enema group with that of the general enema group, we analyzed general characteristics, bowel movement, abdominal examination and related symptoms. Results : Sixty-three patients comprised the Bo-Ryu (n=29) and general (n=34) enema groups. Between the Bo-Ryu and general enema groups, the Bo-Ryu enema was more effective than the general enema in the number of bowel movements, total and corrected amount of stool, tonus of rectus abdominis muscle and abdominal discomfort. However, there were not significant differences in the power of abdominal muscle, digestion and physical power. Among the subgroups, Bo-Ryu enema group was most effective in the number of bowel movements, total amount of stool and tonus of rectus abdominis muscle, and Bo-Ryu enema group was best in the corrected amount of stool and abdominal discomfort. Conclusions : Bo-Ryu enema should be considered as an effective and safe treatment for patients with constipation during the acute stage of cerebrovascular accident.

• Journal of Technology Innovation
• /
• v.14 no.1
• /
• pp.67-99
• /
• 2006

Utilizing the patent application data between 1997 and 2002, this study focuses on analysing the impact of patents on firm value. Especially we attempt to examine the difference of patents between venture firms and general firms. This paper first shows that the number of the patent applications of general firms listed on the securities market is more than that of venture firms listed on KOSDAQ. It is thought that this result is originated from the facts that the size of firms of the securities market is usually bigger than that of the firms of KOSDAQ and that these large firms could manage R&D more efficiently. Second, this paper reports that there is no difference in the ratio of patent maintenance between venture firms and general firms. Both venture firms and non-venture firms would do their best to keep their patents after patent regisration. Third, in the regression of patent index and firm growth, we find that the excellence of patent and the number of patents per employee would have an impact on the growth of firms. Fourth, the regression of patent index and profitability shows that the excellence and the number of patents per employee might have an effect on the profitability of firms.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.18 no.3
• /
• pp.454-462
• /
• 1996

With the increase of population, dramatic urbanization, traffic, leisure and sports, the number of maxillofacial injury has increased markedly. Subsequently the number of motor vehicle accident, sports accident and industrial accident were increased and the number of oral and maxillofacial trauma patients were also markedly increased. A clinical study on 177 patients with facial bone fracture who visited Kangnam General Hospital during 4 years(1992-1995) was done by analysing sex, cause, fracture site, treatment method, complication and involvement of other body part. The results obtained were as follows : 1. The occurrence was more frequent in male than in female with the ratio of 4.2 : 1 and most frequently in twenties. 2. Violence was the most common cause of facial bone fracture. 3. Mandible was the most frequently occurred site and there were more cases of simple fracture(81.9%) than cases of compound fracture. 4. Simple fracture was most frequently occurred(44.0%). 5. In mandible fracture, simple fracture was 86.1%, fracture site was average 1.5 sites, most frequently in symphysis. 6. As treatment methods, open reduction(78.5%) was used more frequently than closed reduction(21.5%). 7. Post-operative complication occurred in 29.4% of the cases. 8. Other injuries that were related to maxillofacial fracture occurred in 28.2%.