• Title/Summary/Keyword: Plate analysis

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RETENTIVE FORCE OF ADJUSTABLE DENTAL IMPRESSION TRAYS WITH DIFFERENT RETENTION FORMS (유지형태에 따른 가변형 치과 인상용 트레이의 유지력에 관한 연구)

  • Song Kie-Bum;Kim Sung-Rok;Park Kwang-Soo;Kim Yu-Lee;Dong Jin-Keun
    • The Journal of Korean Academy of Prosthodontics
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    • v.43 no.1
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    • pp.15-29
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    • 2005
  • Statement of problem. The adjustable dental impression trays were made for being adjusted their width automatically along the width of dental arch. Purpose. The purpose of this study was to investigate the best retentive form of adjustable dental impression tray, and so to make it a more satisfactory product. Material and methods. The eight pairs of adjustable trays were made of ABS(acrylonitrile butadiene styrene) with different distribution of holes and with or without the rim on the border area of them. The experiment was done with the horse-shoe shaped metal plate to pull out the set impression body from the tray, and the tray jig which was made for holding the tray on a lower part of Universal Testing Machine(UTM, Zwick Z020, Zwick Co., Germany). After the impression in the tray was allowed to set four minutes, a tensile force was applied at right angles to the tray which had been previously seated on the jig. The force was applied to measure a maximum retentive force by use of a UTM at a constant strain rate of 100mm per minute. A 2-factor analysis of variance (p<.05) was used to determine whether differences existed among distribution of retentive holes and between rim existing and not. Results. 1 The retentive force of the upper and lower resin tray with 2mm holes on the tray border was highest(25.83/24.98kg). (p<.05) 2. As the tray had more retentive holes, it was less retentive. 3. There was no significant difference in the retentive force of the varied hole intervals in the case of distributing all the area. (p>.05) 4. The rimless trays were more retentive generally, than the rimmed trays except 2 case: upper tray group-all area / 2 mm, intervals and lower tray group-margin only / 2 mm, intervals.(p<.05) 5. Most of the adjustable trays were showed higher retentive force than perforated metal tray except the lower group that perforated on the all area at intervals of 2 mm.

The Comparison on Illustrations of Elementary Science Textbooks in Koaea and Japan (한.일 국민학교 자연 교과서 삽화 비교 연구)

  • Park, Si-Hyoun;Woo, Jong-Ok
    • Journal of The Korean Association For Science Education
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    • v.14 no.1
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    • pp.58-69
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    • 1994
  • In this study, with the problem of "What is the desirable illustrations?", the problem points of the existing textbooks were analyzed, and the opinions of experts concerning desirable illustrations were examined through questionaire survey, and by developing 'Analysis Framework of Illustrations', and Korean-Japanese 'science' textbooks were analyzed and compared with. The conclusions for the direction of korean 'science' textbooks are summarized as follows : 1) The numbers of korean illustrations should be more about two than one of per one page of the existing textbooks. 2) The korean illustrations for the 6th grade should be more largely inserted. 3) The more econmic space utilizing measure should be groped for looking at from the such side. 4) Though the kinds of Korean illustrations are mostly composed of photographs, pictures, illustrations, cartoons, etc. should be positively utilized. and the shapes of photographs should be diversified by such as square, round shape,omissions of background and others. 5) The distribution of players by sex should be considered envenly for male and female from the ascendency of male (1.5: 1). 6) It was found that it is desirable for the formation of role of illustrations of 20% for motive inducement, 45% for guidance for experimentation, 30% for presentation of data, and 5% for presentation of the results of experimentation. 7) The illustrations for guidance for experimentation should present important stages of experimentation process regardless the number of illustration. 8) It would be advantageous for motive induction to find the subject matters as possible as from the children's close actual life. 9) It is necessary to induce more freely method in utilizing Printing plate for inserting illustrations. 10) It is the result of research that the existing Korean textbooks are not suitable in inducing interest, and the positive strategy to induce interest is demanded. 11) It is required to select their location freely in accordance with the content regardless the. 12) In order to develop such illustrations, it is required to cultivate expert illustrators, and more economic investment is required for development of illustrations. The emphasis matters of revision of the 6th educational process of 'Inducement of study motive and emphasis on interest' is the change of presenting form and method of illustrations, which is expected to be rewarded with much good fruits.

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Finite Element Analysis of Stress Distribution in using Face Mask according to Traction Point (훼이스 마스크의 견인위치에 따른 응력분포에 관한 유한요소법적 연구)

  • Oh, Kyo-chang;Cha, Kyung-Suk;Chung, Dong-hwa
    • Journal of Dental Rehabilitation and Applied Science
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    • v.25 no.2
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    • pp.171-181
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    • 2009
  • The objective of this study was to analyse stress distribution of maxillary complex by use of face mask. The construction of the three-dimensional FEM model was based on the computed tomography(CT) scans of 13.5 years-old male subject. The CT image were digitized and converted to the finite element model by using the mimics program, with PATRAN. An anteriorly directed force of 500g was applied at the first premolar 45 degrees downwards to the FH plane and at the first molar 20 degrees downwards to the FH plane. When 45 degrees force was applied at maxillary first premolar, there were observed expansion at molar part and constriction at premolar part. The largest displacement was 0.00011mm in the x-axis. In the y-axis, anterior displacement observed generally 0.00030mm at maximum. In the z-axis, maxillary complex was displaced 0.00036 mm forward and downward. When 20 degrees force was applied at maxilla first molar, there were observed expansion at lateral nasal wall and constriction at molar part. The largest displacement was 0.001mm in the X-axis. In the Y-axis, anterior displacement observed generally 0.004mm at maximum. In the Z-axis, ANS was displaced upward and pterygoid complex was displaced downward. The largest displacement was 0.002mm.

Analysis on PD Pulse Distribution by Defects Depending on SF6 Pressure (SF6 압력에 따른 결함별 부분 방전 펄스의 분포 분석)

  • Kim, Sun-Jae;Jo, Hyang-Eun;Jeong, Gi-Woo;Kil, Gyung-Suk;Kim, Sung-Wook
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.28 no.1
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    • pp.40-45
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    • 2015
  • Electrode systems: a protrusion on conductor (POC), a protrusion on enclosure (POE), a crack in epoxy plate and a free particle (FP) were fabricated to simulate insulation defects in a gas insulated switchgear (GIS). SF6 gas was filled in the electrode systems by 3 bar and/or 5 bar, respectively. Partial discharge (PD) pulses were detected through a 50Ω non-inductive resistor. A calibration test was carried out according to IEC 60270, and the sensitivity was 0.25 pC/mV. PD pulses were distributed in the phase of 50135 and over 95% of them existed in the phase of 55120 for the POC. PD pulses were distributed in the phase of 230310 and over 90% of them existed in phase of 220300 for the POE. PD pulses occurred in the phase of 4060 and 220300 for the crack, and pulse counts were 25% higher in negative polarity than in positive polarity. PD pulses were distributed in every phase unlike to other three electrode systems and the peak magnitude was measured at 118 and 260 for the FP. As described above, PD pulses were observed in positive polarity for the POC, in negative one for the POE, in both one for the crack and the FP. In conclusion, it is expected that the identification rate of defect type can be improved by considering the polarity ratio of PD pulses on the PRPDA method.

Isolation of Antifungal Substances by Bacillus amyloliquefaciens IUB158-03 and Antagonistic Activity against Pathogenic Fungi (Bacillus amyloliquefaciens IUB158-03이 생산하는 항진균물질의 분리와 항균활성)

  • Kim, Hye-Young;Lee, Tae-Soo
    • The Korean Journal of Mycology
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    • v.37 no.1
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    • pp.96-103
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    • 2009
  • For the control of pathogenic microorganisms, Bacillus spp. were isolated from diseased pepper fruits in Korea. Among them, Bacillus sp. IUB158-03 showed high inhibitory effect on mycelial growth and spore germination of C. gloeosporioides and Botrytis cinerea. The strain was identified as B. amyloliquefaciens IUB158-03 based on its physiological, biochemical characteristics and Microlog analysis. The highest level of antifungal substances by B. amyloliquefaciens IUB158-03 were obtained when the bacterium was cultured in medium containing 2% soluble starch, 3% yeast extract, 0.5% tryptone, 0.5% NH4H2PO4, and 1% NaCl (pH 6.0) at 25C for 72 hrs. The antifungal substances were purified by butanol extraction, silica gel column chromatography, preparative thin layer chromatography, and high performance liquid chromatography. The purified antifungal substance was confirmed Rf 0.27 by TLC. This substance exhibited antifungal activity against Fusarium solani, Rhizoctonia solani, Botrytis cineria, Alternata alternaria of plant pathogenic fungi and Trichophyton mentagrophytes, Epidermophyton floccosum, Cryptococcus neoformans of human pathogenic fungi.

A Study on Consumer's Recognition of Frozen Processed Foods and Contamination Levels of Frozen Seafoods (냉동가공 식품에 대한 소비자 인식도 및 수산 냉동식품의 오염 상태 조사 연구)

  • Kang, Su-Jeong;Kim, Ok-Seon;Son, Shih-Hui;Yoo, Hae-Min;Lee, Jee-Won;Jung, Su-Young;Cho, Ah-Young;Yoon, Ki-Sun
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.6
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    • pp.873-883
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    • 2008
  • In this study, we assessed consumers' recognition of frozen foods via a survey study, and monitored the contamination levels of total aerobic bacteria and Escherichia coli in imported and domestic frozen seafoods obtained from five whole sale markets in Seoul. A questionnaire used to assess the perception of frozen food safety and the attitude towards frozen food usage was developed and distributed to 350 adults. A total of 324 questionnaires were subjected to frequency analysis and a chi-square test, using SPSS for Windows. The results of our survey study demonstrated that 44.6% of the respondent consumed frozen processed foods two to three times per month, with dumplings being the most frequently purchased. 70.5% of the respondents selected "convenient cooking" as the principal reason for their frozen food purchases. 58% of the respondents believed that frozen processed food is not safe to eat as the result of food additives and changes in quality during the shelf life period. Consumers most profoundly preferred frozen seafood originating from America, and preferred that from China least profoundly (81.2%). Microbiological analyses demonstrated that the aerobic plate counts of frozen seafood, regardless of origin, fulfill the standard requirements except for one frozen clam (6.6 Log CFU/g), which was a heated-frozen domestic product. In addition, E. coli was isolated from frozen cooked mussels, frozen raw clams and squids, thus indicating that more strict hygienic regulation for frozen seafoods will be necessary to protect the consumer in both domestic and foreign markets.

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A Study on the Natural Frequency of Al Square Plates with a Brass Inclusion using Rule of Mixtures (혼합법칙을 이용한 황동 개재물이 있는 Al 정사각판의 고유진동수 해석)

  • Lee, Youn-Bok;Lee, Se-Hoon;Lee, Young-Shin
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.19 no.4 s.74
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    • pp.399-406
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    • 2006
  • The natural frequencies of Al square plates with a brass inclusion were analyzed by the rule of mixtures. The rule of mixtures is the method to derive natural frequency mutiplying effective inplane wane speed and nondimensional frequency parameters. Numerical models were Al square plates with an inclusion with cantilever type, 2 clamped edge-2 free edge type, 3 clamped edge-1 free edge type and fully clamped edge type. In cantilever type plates, 2 clamped edge-2 free edge type plates and 3 clamped edge-1 free edge plates with an inclusion, good agreement within 10% obtained from rule of mixtures' results and numerical analysis results within inclusion area ratio 1/9. It was found that the natural frequencies of the cantilever type, 2 clamped edge-2 free edge type and 3 clamped edge-1 free edge type plates with an inclusion decrease as the size of inclusion increases when inclusion is located center of plates. And when the density of inclusion is less than the plates, natural frequency of plates with an inclusion increases as the size of inclusion increases.

Antibacterial Effects of Lactococcus lactis HK-9 Isolated from Feces of a New Born Infant (신생아 태변에서 젖산세균인 Lactococcus lactis HK-9의 분리 및 항균활성)

  • Baek, Hyun;Ahn, Hye-Ran;Cho, Yun-Seok;Oh, Kye-Heon
    • Korean Journal of Microbiology
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    • v.46 no.2
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    • pp.127-133
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    • 2010
  • The purpose of this work was to investigate the antibacterial activity derived from a lactic acid bacterium, Lactococcus lactis HK-9, isolated from the feces of a 2-day newborn infant. We characterized the physiological and biochemical properties of this strain. Both the BIOLOG system and phylogenetic analysis using 16S rRNA sequencing were utilized for identification, and the strain was assigned to the Lactococcus lactis species, designated as L. lactis HK-9, and registered in GenBank as [GU936712]. We monitored growth rate, production of lactic acid and acetic acid as metabolites, and pH during growth. The maximum concentrations of lactic acid and acetic acid reached 495.6 mM and 104.3 mM, respectively, and the initial pH of the cultures decreased from 7.0 to 4.1 after incubating for 60 h. HPLC was used to confirm the production of lactic acid and acetic acid. Significant antibacterial activity of the concentrated supernatant was demonstrated against Gram-positive (e.g., Staphylococcus aureus, Enterococcus faecalis, Listeria monocytogenes, MRSA) and Gram-negative (e.g., Escherichia coli, Salmonella enteritidis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Shigella sonnei) bacteria by the plate diffusion method. The antibacterial activity was sensitive to protease, and the molecular weight of the presumed bacteriocin molecule was estimated to be about 4 kDa by tricine-SDS-PAGE.

A Study on Electrodewatering Filter Press Technology for Improvement of Dewarterability of Waterworks Sludge (정수슬러지 탈수효율 향상을 위한 전기필터프레스탈수에 관한 연구)

  • Lee, Jung-Eun;Lee, Jae-Keun
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.10
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    • pp.1009-1015
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    • 2006
  • The elcetrodewatering filter press(EDFP) which had anode and cathod plates to be set between filter plates was built for reducing the waterworks sludge and improving performance of dewatering equipment. Several tests to compare the dewaterability with conventional mechanical filter press dewatering(MDEP) and EDFP was conducted through this equipment. As test results, filtration amount discharged from EDFP measured 43.2 kg which increased against MDFP, and cake weight measured 4 kg which was two times against MDFP. The water content of dewatered cake from EDFP was 55wt% and dewatering velocity was 2.3 kg/m2cycle. This water content decrease 20% and dewatering velocity increased 30% with compare to the MDFP. That is to say, EDFP constructed from electrodewatering mechanism increase filtrate discharging amount, which make dewatering velocity increase and produce the low water content dewatered cake against MDFP. Energy consumption of EDFP is analysed to 400 kwh/DS ton. The results to analysis the economical aspect considering the power consumption and the handling cost decline as sludge volume reduction due to producing the low water content cake showed that expenses to handle sludge of 1 ton by dry solid base cut down on 20,000 won. If considering several test aspects, it was analysed that EDFP was excellent in the side of performance as well as economical suitability.

Development of a Personal Compound Stimulus Device for Skin-care (개인용 피부미용 복합자극기 개발)

  • Lee, Jeon;Kim, Chi-Hyun;Chung, Geum-Hee
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.49 no.1
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    • pp.12-19
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    • 2012
  • Recently, the market of skin-care device has been steadily growing up. In this paper, we tried to develop a personal compound stimulus device more competitive than existing products. As the compound stimulus, biochemical stimulus of herbal extraction fluid, thermal stimulus of plate-shaped carbon fiber heater, and optical stimulus of near infrared LED were selected. By some evaluation tests, the thermal stimulation part and the optical stimulation part were found to be developed properly. Additionally, the efficacy of the mixed stimulus of thermal and optical stimulation was tested in C2C12 mouse myoblast. Through RT-PCR analysis, it was found that, by the developed compound stimulus, the expression of collagen I mRNA and collagen III mRNA increased by 4.9 and 1.3 times respectively.