• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• 제26권2호
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• pp.133-145
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• 1996

Aspirating or swallowing foreign bodies is a common occurrence. If they are wholly or partly radiopaque, their localization in and progress through the gastrointestinal tract can be more effective. Of the dental origin foreign materials swallowed, the most common things are fragments of anterior maxillary partial denture. But the radiopacity of denture base resins is not sufficient to determine the location of the objects. The purpose of this study was to develop a radiopaque dental acrylic resin, which has clinically detectible radiopacity with minimal change of mechanical properties and color. The radiopacity, color change(CIE 6..E) and microhardness of acrylic resins were determined after mixing barium sulfate or iodide compound. Thermocycling course was conducted to determine the change of characteristic of resins after using for a long time in the mouth. Five or ten percent of barium sulfate to total weight of cured material was mixed with heat curing dental acrylic resin or chemically curing orthodontic resin. In the case of iodide compound, the mixing ratio was two or three percent. After mixing the high radiopaque materials, resin was cured to 20×20×2 mm plate, polished with #600 sand paper and finally polished with Microcloth(Buehler). The specimens were thermocycled in 5 and 55 t distilled water for 2,000 times, and the measurement of radiopacity, color and Vickers hardness was repeated every 500 times thcrmocycling. The radiopacity of specimens on the X -ray films was measured with densitometer(X-rite). The color change was detennined with differential colorimeter(Model TC-6FX, Tokyo Denshoku), and the Vickers hardness number was measured with microhardness tester(Mitsuzawa). The following results were obtained : 1. All the three variables, the kinds of acrylic resins, the mixing or the kinds of high radiopaque materials and thermocycling, had combined effect on the radiopacity of the dental acrylic resins(p<0.0l). 2. The two variables, the mixing or the kinds of high radiopaque materials and thermocycling, influenced on the radiopacity of the dental acrylic resins(p<0.01). But the kinds of acrylic resins did not influence on the color change of mixed dental acrylic resins(p>0.05). 3. Each of the three variables, the kinds of acrylic resins, the mixing or the kinds of high radiopaque materials and thermocycling, influenced on the radiopacity of dental acrylic resins(p<0.0l). 4. The high radiopaque materials used in this study did not yield clinically usable radiopacity, and the color change was great after mixing those materials.

• The Journal of the Convergence on Culture Technology
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• 제6권1호
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• pp.471-476
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• 2020

We propose an practical embodiment-based programming training course for middle school students using Arduino and conduct survey before and after the curriculum. Arduino is an open source physical computing platform that integrates the IDE used in processing language. It is a low-cost, relatively simple I/O interface compared to other platforms, and because of its practical formability, it is educational material suitable for programming. Subsequent surveys will provide feedback on changes in cognition of programming needs and improvement in thinking skills. In this study, the program based on embody-based programming using Arduino was conducted for 8 weeks for each first grade, and 112 middle school students for two years from '16 to '17. Based on the theoretical and practical training, the training was based on the application of the ultrasonic sensor to the RC car and the preparation of the adduction quadrotor drone. The purpose of this study is to prove that the recognition, necessity, and programming education of middle school students are effective for the improvement of thinking ability through the program based on embody-based programming using Arduino.

• Journal of Plant Biology
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• 제1권1호
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• pp.11-20
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• 1958

I. Assumption: Mo-kam-ju, Koelreuteria paniculata is a woody plant mainly cistributed over Northern China. Its sporadic growth along the beaches of Korea and Japan is assumed to have been sowed by the seeds transported adrift on the current across the ocean. II. Use and Growth of the Plant: In China, this plant has been cultivated from early times mainly at temples, it seeds being used as rosaries, its flowers for yellow dyes and medicine for the eyes, and its leaves for black dyes. In Korea and Japan, these plants have been cultivated at temples and used as the material for rosaries. No natural growth of these plants was reported until 1919. III. Discoveries: In this domestic area, Dr. Chung Tae Hyun discovered the plant on the beach between Cho-Do and Chang-san-kot, Hwang-Hae Prov. in 1920. The reporter discovered them on the beach at Buk-Ni, Duk-jok-Do in 1948, at An-Hung in 1956 and on the beach at An-min-Do in 1957. In the Japan area, it was discovered for the first time twenty years ago, mainly along the coast line of the Japan Sea and some along the eastern coast line, at Subo, Yamaguchi Prefecture facing the Pacific Ocean. IV. Study and Experiment: A. Seed The seed coat is thick, non-permeable and floatable. A number of seeds were immersed in artificial sea water and fresh water separately. The seeds remained there for a hundred and forty-five (145) days from April 6, 1957 to August 29, 57. Thirty one seeds out of the fifty immersed in salt water and twenty seeds out of the fifty immersed in fresh water remained on the surface of the water, proving them to be non-permeable to both sea and fresh water. Of course, these had retained their germinating capabilities. Five (5) seeds out of twenty from the fresh water and six (6) out of thirty-one from the sea water were successfully germinated after a hole had been drilled in the seed coat and they had been planted. Thus their floating capability, non-permeability and germinating capability after a possible 145 day trip on the flowing currents has been proved satisfactory according to the assumption made above. B. Current As shown in the Data 2 and 3, the sea current initiated in the Pohai Sea flows westward down along the coast line of Korea reaching the southern part during the autumn and winter seasons. This fact also is in favor of the reporter's assumption. V. Discussion and Conclusion: The reporter concludes that, as discussed above, Koelreuteria paniculata which originates in Northern China is transported adrift on the flowing sea current to our western coast line, and also the coast lines of Shantung and Kuangtung of China and it is germinated on the sandy beaches forming new plants. Thus, the seeds drifted down on the southern beach of Korea and have been transported to the Japanese coast, adrift on the Tae-Ma current. Upon fruition, the seeds of the plants which settle on the coasts of western Korea and Japan will migrate to new places. It can be, however, assumed that while the thickness and nonpermeability of the coat enables the long travel in the water, this also can compose a difficulty in germination, consequently in developing a new distribution of this species.

• Korean Journal of Bronchoesophagology
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• 제16권2호
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• pp.145-148
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• 2010

Background: Laryngeal papillomatosis, which is cased by human papillomavirus, is the most common benign neoplasm of the larynx. However, the prognosis of this disease remains really unpredictable. The aim of this paper is to determine whether any clinical features at the time of diagnosis could predict its course. Material and Method: Eighty-six patients treated at our institution during the last 20 years were analyzed retrospectively. All patients had microsurgery under general anesthesia. All patients' follow-up period was more than 1 year. We divided the patients into 1) Juvenile versus adult group based on their age 20, 2) single surgical method with laser versus dual surgical method with laser and microdebrider group, and 3) single subsite versus multiple subsites group. And we compared the therapeutic outcome. Results: The recurrence rate was 100% (15 patients) in the JP group and 56% (40 patients) in the AP group. Juvenile versus adult group was the only independent prognostic factor by univariate, and multivariate analysis. Microdebrider resection technique and multiple subsites were not associated with treatment result. Time period from the first surgery to recurrence detection was different statistically only for the age group. The number of surgery in the JP group ranged from 1 to 31 (mean 8.8). In the AP group the number of surgery ranged from 1 to 25 (mean 3.7). It was statistically different. Conclusion: Prognosis for the laryngeal papillomatosis remains unpredictable. Only patients' age was the only independent prognostic factor.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.331-336
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• 2007

The importance of a building management is embossed at construction industry and the concernment about a lengthening longevity and a efficient management of construction project is concentrated. At present, a study about maintenance management of existing building is progressed and normal papers concentrate in partial construction project for showing management method. This paper proposes Management method that make use of RFID/USN at the whole course of construction project that is composed plan, design, supply, construction, operation, maintenance management and so on. First of all, this paper analyzes process and applicable scope of RFID/USN at construction project. At each step, use scope, location, method and so on are decided at plan, design step and equipment, human power, materials and so on are established at supply step. real time progress, human power, safety, material, equipment management and so on put in operation at construction step and building is managemented real time by established sensor tag and wireless sensor network. This paper want to helps efficient project progress and management and presents convenience of maintenance management.

• Journal of Environmental Policy
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• 제10권2호
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• pp.3-19
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• 2011

Nagoya Protocol designed to establish criteria about material trade of biological genetic resources(ABS) was adopted in the 10th conference of the Parties to the Convention on Biological Diversity. In the course of the negotiation for adoption of the protocol, there was conflict between developed and developing countries, resource-rich and poor countries, and multinational corporations and environmentalists. This study investigates conflict process, subjects, issues and major factors in the negotiation case, and analyzes the negotiation by using the Conflict Management Process. To develope conflict management strategies for various conflict cases, we examine previous studies and analyze the intersectional conflict factors of this case and general cases, such as Fundamental side, Resource-allocation side, and Communication/Information-sharing side. These analyses of conflict prevention/resolution of the ABS negotiation show the importance of building mutual trust among stakeholders, enhancing mediator training, and constructing appropriate legislative/policy systems for successful conflict management.

• 대한공업교육학회지
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• 제39권1호
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• pp.128-142
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• 2014

The purpose of this study was to provide a basis information for the education direction of 'creative engineering design' lesson to highschool students and pre-technology teachers by analyzing pre-experienced the d epartment of technology professors' recognitions, according to the newly opened unit 'creative engineering design' in 2009 revised highschool technology home economics education curriculum. The survey questionnaire was composed of 34 questions and collected from 16 department of technology education professors. The data was analyzed by SPSS program. The results of study were as follows : First, in 'creative engineering design' educational objectives, the highest average level(M) of response was problem solving ability, the opportunity of engineering experience and creativity improvement were followed. In the response about 'creative engineering design' educational contents, the average level(M) of the creative thinking method education was the highest(3.94). and the following important level was the write training education for presentation. Second, in the 'creative engineering design' educational areas, the professors preferred the idea conception, design, and production manufacturing area. In the teaching learning method, the average level(M) of design-based learning method was the first. and PBL, problem solving method were favored Third, in the 'creative engineering design' lesson manage, the secure of practice room and material cost, and the check of the progress situations were needed preferentially. In the education assessments, various and combined assessment preferred such as production, portfolio, and presentation. Fourth, in the pre-technology teachers' lesson of the university course, the product manufacturing level was preferred production to improve uncomfortable thing in life. The major difficulty in product manufacturing was the lack of major knowledge and product conception.

• Journal of Chest Surgery
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• 제37권5호
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• pp.432-437
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• 2004

Background : Solitary fibrous tumors of the pleura (SFTP) is one of rare neoplasms that originated from submesothelial mesenchyme. Clinical course or extent of surgical resection is not well known. Material and Method: We retrospectively reviewed all the clinical records of the patients who had undergone surgical resection of benign and malignant SFTP, Result: Twenty two (male female 14 : 8) patients were enrolled and mean age was 50.2(range 25∼83). Number of symptomatic patients at the time of diagnosis was 13 (59%) and the most common symptom was dyspnea. Operative approach was carried out through thoracotomy (n=14) or video-assisted thoracic surgery (n=8). Mass excision was performed in 12 cases and en bloc resection including adjacent structure in 10 cases. In all cases complete resection was performed. There was no operative mortality. Malignant SFTP were 11 cases and benign SFTP 11 cases. Local recurrences (n=2) or distant metastasis (n=6) occurred only in malignant SFTP. Conclusion: Number of symptomatic patients, on bloc resection, and recurrence was more in malignant SFTP. Although complete surgical resection is known as treatment of choice for SFTP, further study should be performed about systemic therapeutic modalities pre- or postoperatively to control recurrence and metastasis.

• Korean Journal of Community Nutrition
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• 제4권1호
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• pp.83-94
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• 1999

This study was carried out to investigate the general characteristics of public health nutritionists, the current status of nutrition services operation, the recognition about nutrition services of public health center related man power, the job satisfaction and self-assessment and the need for a retraining course of public health nutritionists. The subjects were 58 public health nutritionists who responded to the questionnaire distributed at the annual retraining program in 1998. The results of this study are summarized as follows. 1) 46.5% of the nutritionists were 26-30 years old, 62.1% were 4 year university graduates 74.1% were food and nutrition majors and 51.7% were daily workers. 2) Among the public health center-related manpower, the recognition about nutrition services was the highest for the manager of family health section, followed by the head of public health centers, and then the general nurse in public health centers. 3) The ranking of the reasons for job satisfaction of the public health nutritionists was, relationship with colleagues(3.84), inhabitants response after nutrition counselling(3.53), specialized value realization/conviction about duty(3.35), contents of the work(3.10), value achievement(3.08), self achievement/development(3.00), self discretion(2.92), participation in policy decisions(2.90), work load(2.75), chance of retraining and acquisition of new information(2.73), working environment(2.69), supervisio $n^port by superiors(2.67), salary(2.38), supply of necessary education material, technique(2.37), and budget security(2.22). 4) The satisfaction of the inhabitant's responses after nutrition counseling was the highest among the 4 year university graduates(p<0.05), the satisfaction of the specialized value realization/conviction about duty was the highest among the nutritionists 26-30 years old(p<0.05). Food and nutrition majors(p<0.05) and those having worked less than 3-5years at public health centers also showed much satisfaction(p<0.05). Satisfaction with the salary was the lowest among the food and nutrition majors(p<0.01) and daily workers(p<0.001). The satisfaction with the participation in policy decisions was the lowest among the daily workers(p<0.01). 5) The ranking for the level of self-assessment were, nutrition and dietetic practice(2.92), communication(2.80), management(2.77), public health science and practice(2.66)(p<0.01). The general characteristics such as the level of education, major, employment condition, current public health center's tenure, and charge experience of the nutrition guidance work were not significantly related to self-assessment except the management part(p<0.05). The higher the satisfaction of specialized value realization/conviction about the duty, the better the total score on the self-assessment(p<0.05)..

• Journal of The Korean Ophthalmological Society
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• 제59권12호
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• pp.1190-1194
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• 2018

Purpose: We report a case of unilateral, focal, pigmented paravenous retinochoroidal atrophy (PPRCA). Case summary: A 46-year-old female visited our clinic in complaint of a vague problem with her right eye identified during a general medical examination. The visual acuity (without correction) of both eyes was 1.0. Slit-lamp examination of both eyes revealed no specific signs. Fundus examination of the right eye revealed focal, bony-spicule-shaped retinochoroidal atrophy with pigmentation along the course of the superior retinal vein. A fundus autofluorescence examination revealed principally hypofluorescence with some hyperfluorescence at the margin of the atrophic retinochoroidal lesion. Optical coherence tomography revealed mixed clumping and atrophy of the retinal pigment epithelium (RPE) layer and thinning of the choriocapillaris layer. Fluorescence angiography revealed a window defect and blockage at the site of the lesion (the fluorescent material did not enter the lesion). The site of the window defect was in correlation with the atrophic RPE region. The site of the blockage at lesion also matched with the site of the regional pigment clumping. No definite leakage was observed. Conclusions: To the best of our knowledge, this is the first case of unilateral focal PPRCA reported from Korea.