• Journal of Periodontal and Implant Science
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• v.24 no.1
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• pp.131-143
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• 1994

For maintenance of exposed implant in healthy state, it is necessary to treat the surface of implant fixture and provide the surface adjustable to surrounding tissues. Variable techniques have been introduced such as citric acid and air-abrasive system to treat the failed implant. Although when the rough surface of HA coated implant was exposed to oral environment, the surface treatment method with citric acid or air-abrasive system is effective for removal of bacterial endotoxin, it is unsuccessful to prevent plaque deposition due to difficulty in removal of rough surface of HA coated implant. Thus, in this study the method that removes bacterial endotoxin and makes smooch surface without alteration of surface characteristics was studied. HA coated disc manufactured by IMZ Co. Was treated with high speed diamond bur, low speed diamond bur, stone bur, rubber point, jetpolisher. And then its surface state was examined with profilometer and SEM to evaluate the surface smoothness, and its surface component was analyzed with EDX to evaluate wheter the surface characteristics were altered or not. As a result, following results were obtained. When the surface roughness of each implant disc was measured by profilometer, the group I showed a $R_{max}\;2.11{\mu}m$ and the group II, III, IV, V showed a $R_{max2}\;4.17{\mu}m$, $7.28{\mu}m$, $8.61{\mu}m$ and $39.44{\mu}m$ respectively. That is, surface smoothness was highest in the group I and it has been gradually decreased in the group II, III, IV and V. Under the SEM examination, the group I showed relatively smooth surface and the group II showed slightly rougher surface than the group I due to partially remaining HA particles while most HA particle was removed. The group III and IV showed rough topography due to HA particles that was not grinded, and HA coated surface in group V showed very irregular surface with deep groove and prominence. In cross-sectional view, the group I showed uniform surface, and the group III, IV showed rough surface due to remaining HA particles but the thickness of HA coating was remarkably reduced. The group II has similar pattern in group I, and the group V showed about $40{\mu}m$ thickness although it was not constant. By analysis of surface component with EDX, the group II in which the grinding was effective showed a small quantity of calcium and phosphorous and the group III, IV, in which the grinding was incomplete showed calcium and phosphorus peak. In all experimental group, no other than titanium, aluminum, calcium, phosphorus was observed.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.1
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• pp.45-52
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• 2020

This study analyzed the components contained in the pine needles of first and second-year-olds to analyze the factors that the in vivo content of inorganic elements affects the sex determination of pine trees. In response, the plan for pine tree plant and maintenance was intended to be presented in consideration of the reproductive environment and physiological characteristics. The results are as follows. First, last year, when there were many encyclopedias, the analyzed N(%) content was found to be high. The nitrogen content of the previous year's soil was found to affect the production of the spheres the following year. This is believed to be possible to reduce the rate of Pine pollen produced in the new plant in the following year through a dispute over quality consumption in the spring of the previous year. Second, the weapons elements involved in the Pine cones and the generation of the Pine pollen in the new plant appeared to be P(%), K(%), Ca(%), and Fe(%). However, the nutrients from the previous year's leaves of Ca(%) and Fe(%) were found to have a low influence on the sex determination of first-year pine trees. Because Ca(%) and Fe(%) are not able to move nutrients accumulated in aging organs due to the nature of the components, feeding nutrients in the fall when the growth of the previous year's branches is reduced is expected to affect oral generation. Third, pine trees are extremely positive and Pine pollen is related to the time of the northeast wind. Therefore, it is believed that it would be good to be located in the northern direction, where the sunlight is good, in an outdoor space. In addition, it is important to use vaginal consumer products in spring and carry out a quarrel involving Mg and Fe during fall to reduce the effect of the Pine pollen, which is an outdoor plant. This is an important part of maintaining and managing pine trees in outdoor spaces as well as the sex determination of pine trees. This study suggested that plant planning, which derives the correlation between pine inorganic element content on sexual determination and takes into account the physiological characteristics of pine trees, is an important issue in the creation of outdoor space. Follow-up research on other factors affecting pine tree sex determination is expected.

• Journal of dental hygiene science
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• v.15 no.3
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• pp.265-271
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• 2015

This study has an objective not only to be helpful to the understanding about students' career and employment preparation by investigating the present conditions which are related with vocational consciousness and job values of dental hygiene department graduating students. Study subjects were 350 female graduating students in 3-year-course College, dental hygiene department at five areas of Seoul, Gyeonggi, Gangwon and Gyeongnam. Data were analyzed using IBM SPSS Statistics ver. 19.0. Regarding job values, job prospect of dental hygienist is a little developmental (55.2%) and institution hoping to work is dental clinic (43.2%), reasons for employment in major area are good wage and working environment (24.0%). And regarding opinion about job, dental hygienist job is a measure for living income (69.7%). Regarding job selection conditions, 35.0% subjects replied good human relationship. In the questionnaires regarding professional job in vocational consciousness category, results showed high percentages in that 'the occupation is a job in charge of oral health improvement'; regarding academic area, 'scaling should be done better than dentist'; regarding human relationship, 'harmony between colleagues is closely related with job efficiency'; regarding work ethics, 'development of dental hospital (clinic) and dental hygienist is correlated.' In vocational consciousness of study subjects, higher major satisfaction showed significant differences in professional job consciousness and work ethics consciousness (p<0.05) and the correlation results in vocational consciousness areas showed all statistically significant correlations (p<0.01). In case that the characteristic in one type is higher among 4 types, all other types showed high characteristics and also showed high general vocational consciousness.

• The Korean Journal of Archival Studies
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• no.13
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• pp.179-203
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• 2006

This study develops the process and method of official administration documents which have remained ill-balanced like the official documents of the government-general of Chosun(the pro-Japanese colonial government (1910-1945)). At first, the existing Appraisal-theories are recomposed. The Appraisal-Theories of Schellenberg is focused valuation about value of records itself, but fuction-Appraisal theory is attached importance to operational activities which take the record into action. But given that the record is a re-presentation of operational activities, the both are the same on the philosophy aspect. Therefore, in the case that the process - method is properly designed, it can be possible to use a composite type between operational activities and records. Also, a method of the Curve has its strong points in the macro and balanced aspect while the Absolute has it's strength in the micro aspect, so that chances are that both alternate methodologies are applied to the study. Hereby, the existing Appraisal theories are concluded to be the mutually-complemented things that can be easily put together into various forms according to the characteristics of an object and its situation, in the terms of the specific Appraisal methodology. Especially, in the case of this article dealing with the imbalance remains official-documents, it is necessary to compromise more properly process with a indicated useful method than establishing a method and process by choosing the only one theory. In order to appraise the official-documents of the pro-Japanese colonial government (1910-1945), a macro appraisal of value has to be appraised about them by understanding a system, functions and using the historical-cultural evolution, after analysing Disposal Authority. From this, map the record so that organization function maps are constructed regarding the value rank of functions and detailed-functions. After this, establish the appraisal strategy considering the internal environment of archival agencies and based on micro appraisal to a great quantity of records remained and supplying other meaning to a small quantity of records remained for example, the oral resources production are accomplished. The study has not yet reached the following aspects ; a function analysis, historical decoding techniques, a curve valuation of the record, the official gazette of the government general of Chosun( the pro-Japanese government for 1910-1945), an analysis method of the other historical materials and it's process, presentation of appraisal output image. As the result, that's just simply a proposal and we should fill in the above-mentioned shortages of the study through development of all the up-coming studies.

• The Korean Journal of Archival Studies
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• no.20
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• pp.77-114
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• 2009

The actual conditions of the labor unions are primitive. First, there is no good records management regulation. At this research, I found it that most regulations of the labor unions were all the same. I think they have been copied a kind of one of originality. Second, the definition of records were very narrow, like documentary evidence. Third, the classification, filing, disposal regulations are the below level of the public institution in 1970s. Fourth, there are no standards of the records scheduling for the labor records. What kind of labor records have the historical values? I could not find, only the documentary evidence value. So, I think The actual conditions of the labor unions are primitive. I investigated the collections of the Southern Labor Archives in USA. There were many kind of records. For example, the records of regional labor unions also central labor unions, pamphlets, journals, photos, personal records, oral history, organizational records like protocols article of associations internal rules, minute books etc. Like this the collections of the Southern Labor Archives in USA are very various. But our actual conditions of the labor unions is far from that. Rather, we just have tried collected records for publishing the white papers. But this habitual practice would not be desirable. Because they must manage the records from the producing time. Mostly, 'laborer history HANNAE' were organised, and they are trying the collecting and management of the labor records. Also They are trying the computerizing, compilation. 'HANNAE' has the condition for the transformation of the labor archives. But if they want to be really, they must make the records management infra and so, should normalize the record management firstly. For example, They must be keep the standardized records management regulations, records scheduling redesigned. the developing standard model for the records management. And they have the vision for the hub of the labor archives. When coming to this, it will be realized the labor archives Now the records for the working class are disappearing. The managing the records for the labor is another labor movement. All together should join it. But I think the supporting of the archival science research colleagues will be the essential part.

• Journal of the korean academy of Pediatric Dentistry
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• v.50 no.3
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• pp.318-333
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• 2023

The purpose of this study is to analyze changes in dental trauma in children under the age of 12 during the period of Coronavirus Disease 2019 (COVID-19). March 2020, when COVID-19 was officially declared a pandemic by the World Health Organization, was set as the starting point for COVID-19. From March 2018 to February 2020, subjects in the pre-COVID-19 period were classified as the Pre-COVID-19 group, and from March 2020 to March 2022, subjects in the post-COVID-19 period were classified as the COVID-19 group. Information related to trauma was collected through electronic medical records. The number of trauma patients before and after the outbreak of COVID-19 decreased significantly. During the COVID-19 period, there was no significant difference in the male-female ratio or the distribution order of age groups. In the COVID-19 group of permanent teeth, the ratio of trauma caused by personal mobility was higher than trauma caused by sports. In the COVID-19 group of permanent teeth, the ratio of crown fracture with pulp involvement was significantly higher than the ratio of crown fracture without pulp involvement. Changes in trauma patterns caused by COVID-19 were observed more clearly in school-aged children than in preschool children. In a pandemic situation such as COVID-19, it is expected to be used as a good educational basis for knowing that frequent diagnoses can change due to changes in the environment.

• Journal of dental hygiene science
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• v.4 no.1
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• pp.21-25
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• 2004

In modern times, children's trauma is increasing every year because of car accidents and life environment changes. There is a limit to prevent traumatic damage for oral cavity organization. The fundamental data of trauma treatment and prevention will be presented through the survey and analysis of traumatic teeth damage. I examined 113 patients from Oct. 4th, 2000 to Feb. 27th, 2004 at Dept. of Children's Dental Clinic, Kangnung National University. The results are as follows. (1) The trauma frequency of male subjects is higher than that of female at a rate of 2.05:1. The average age is 5.27 for men and 5.27 for women. The highest percentage of trauma patients is among 2 year old children. It is 21.2%. (2) A patient survey was taken at a trauma treatment hospital. On the first day 34.4% of the patients had come to receive treatment of their first set of teeth. However, after a week, 38.8% of the patients had received treatment on their permanent teeth. (3) As a result of falling, 59% of patients needing treatment on their first set of teeth. 55.1% of patients is permanent teeth. As a result of bump against physical solid, 26.6% of patients is the first set of teeth and 26.5% of patients is permanent teeth. (4) Teeth damage happened at home. 42.1% were male. 35.1% were female. According to trauma, 59.4% of teeth damage happened at home. 28.6% of permanent teeth damage happened at school or kindergarten. (5) According to trauma, the number of teeth damaged was in the first set of teeth are as follows: 56.3%, one-31.3%, three or four-6.3% each. For permanent teeth: two-46.9%, one-28.6%, four over-16.3% and three-8.2%. Over four teeth is larger number for permanent teeth. (6) 56% of first set of teeth patients and 43.4% of permanent teeth patients were male. 56.8% of first set of teeth patients and 43.2% of permanent teeth were female. Trauma happened to both male and female frequently in the first set of teeth. (7) Most of the tooth damage which was in the first set of teeth and permanent teeth was done to the upper jaw. 75% of patients are the first set of teeth. 63.8% of patients are permanent teeth. Trauma is very high in the two mid teeth of the upper jaw. (8) According to trauma survey, 30.2% is from impulse. 28.0% is from crown fracture, 14.7% is from depression. 8.9% is from concussion. 7.1% is from full dislocation of a joint. 2.2% of patients are extrusion. 1.8% is from displacement. According to teeth damage trauma, 35.8% is pulse in the first set of teeth. The breaking of the crown of a tooth happened a lot in permanent teeth. (9) According to data, 43.2% of teeth damage in the first set of teeth goes without treatment. In permanent teeth, it is 38.9%. After treatment, 22.0% of first set of teeth treatment requires a dental pulp treatment. In permanent teeth, which is used for temporary acid etching resin restoration.