• Title/Summary/Keyword: 재료 유사성

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An experimental study of cutting efficiency of air-driven diamond burs on human tooth (수종 air-turbine 다이아몬드 버의 절삭 효과에 관한 실험적 연구)

  • Hong, Jin-Sun;Yeo, In-Sung;Kim, Sung-Hun;Lee, Jai-Bong;Han, Jung-Suk;Yang, Jae-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.49 no.1
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    • pp.1-7
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    • 2011
  • Purpose: The purpose of this study was to investigate the cutting efficiency of coarse grit diamond burs with air-turbine handpiece on natural tooth. Materials and methods: Four groups of coarse grit diamond bur were selected: Komet (A), Shofu (B), Premier (C), and Mani (D). The extracted maxillary central incisors were used, and ten cuts were made on each specimen, using the rotary diamond burs. The surface of each bur was measured at the upper, middle, and bottom of the bur with confocal laser scanning microscope and imaged with SEM. The data were analyzed with one-way ANOVA and t-test at the significance level of 0.05. Results: The surface roughness was measured. At the A diamond bur, the Sa values were 52.93μm52.93μm, 48.32μm48.32μm, 46.79μm46.79μm, 45.06μm45.06μm, and 43.43μm43.43μm for control, test 1, 2, 3, and 4 respectively. The Sa values were 50.68μm50.68μm, 45.62μm45.62μm, 44.41μm44.41μm, 44.10μm44.10μm, and 42.46μm42.46μm for B diamond bur, 58.02μm58.02μm, 55.53μm55.53μm, 52.22μm52.22μm, 48.26μm48.26μm, and 45.36μm45.36μm for C diamond bur, and 50.11μm50.11μm, 46.73μm46.73μm, 45.46μm45.46μm, 42.58μm42.58μm, and 41.80μm41.80μm for D diamond bur. Surface roughness after each bur use showed significant changes, but no significant difference was found in surface roughness change between bur systems. Conclusions: Surface roughness in the same bur system showed significant differences after each tooth preparation. However no statistically significant differences were found in surface roughness between bur systems. The SEM images between control and test 4 showed the abraded particles.

Causes of Childhood Injuries Observed at the Emergency Rooms of Five Hospitals in Taegu (대구시내 종합병원 응급실에 찾아온 소아사고 환아의 사고원인)

  • Park, Jung-Han;Bae, Yeong-Sook
    • Journal of Preventive Medicine and Public Health
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    • v.21 no.2 s.24
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    • pp.224-237
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    • 1988
  • To determine the causes of and related factors to childhood injuries, the emergency room records and inpatient medical records were reviewed for 4,849 injured children out of 15,790 pediatric patients(<15 years old) who visited the emergency rooms of 3 university hospitals and 2 general hospitals in Taegu from 1 January to 31 December 1987. Out of total injured children, 54.675 were 3-8 years old and the male to female ratio of the total injured children was about 2:1. The leading causes of injury were falls and slips (29.1%) and traffic accident(28.2%). The frequency of injury was higher in May-October than the rest of months and 51.6% of the injuries occurred between 15 and 20 o'clock. Falls and slips took place most frequently at the stairway(25.7%). The most common interpersonal violence was inflicted injuries(85.6%) and there were 11 child rapes. Dog bites accounted for 67.6% of all biting injuries and it occured 2.9 times more in male than in female. CO intoxication was the most common cause of poisoning (45.3%) and scalding accounted for 85.2% of all burns. Common places of drownings were river (32.2%), swimming pool (22.6%) and construction site(19.3%). To prevent childhood injuries, it is recommended to eliminate the hazardous environmental factors, to provide safe playgrounds, to educate the children for safety from kindergarten and the general public through mass communication, to establish a strict safety standard for houses, public buildings and facilities, and playgrounds.

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Studies on the Improvement of the Fishing Efficiency of Purse Seine in the Sea Area of Cheju Island -The Changes of Seine Volume and Tension in the Purseline During Pursing- (제주도 주변해역 선망의 어획성능 향상에 관한 연구 -짐줄 체결 중 선망의 용적과 짐줄의 장력 변화 -)

  • 김석종
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.35 no.2
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    • pp.93-101
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    • 1999
  • A simple experimental method was used in an attempt to realize the elevation of the fishing ability of purse seine in the sea area of Cheju Island, the changes of seine volume and tension in the purseline during pursing. Experiments carried out on the six types simplified reduced model seines which were made of knotless nettings. The nettings were woven in different leg length 4.3, 5.0, 5.5, 6.0, 6.6 and 7.7mm of polyester 28 tex two threads two-ply twine, and each of the seines were named I, II, III, IV, V and Ⅵ seine. Dimension of seine models were 450cm for corkline and 85cmfor seine depth, each seines rigged up 160g of float for a floatline and 50g (underwater weight) of lead for a leadline. These model purse seines were made of the scale of 1/200 of its full scale, a 120 ton in the near sea of Cheju Island. Designing and testing for the model purse seines were based on the Tauti's law. Experiments were measured in the observation channel of a flume tank at the static conditions set up shooting and pursing equipments. Motion of purse seine during purse line was recorded by the two sets video camera for VTR which were placed in top and front of the model seine. The reading coordinate of seine volume carried out by the video digitization system, disk data for the purseline tension. An analysis were performed on the changes seine volume and tension in the purseline during pursing. The results obtained were as follows: 1. The seine volume during pursing was largest for Ⅵ seine with smallest d/l followed by V, IV, III, II and I seines, and tension in the purseline was small. 2. Seine volume during pursing can be expressed by the following equation; CVt=l-EXP[{2.79 (d/l)+0.35}t-33.37 (d/l) + 0.57] Where CVt is volume ratio, d is twine diameter, l is leg length and t is pursing time (sec). 3. Tension in the purse line during pursing can be expressed by the following equation; T= 1- EXP {0.57t + 13.36 (d/l)+2.97} Where T is tension (kg) in the purseline during pursing.

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Development and Usefulness of Acrylic Needle for Percutaneous Bone Biopsy (경피적 골생검용 아크릴 바늘의 제작과 유용성)

  • Kim, Tae-Hyung;Shin, Myung-Jin;Shin, Ji-Hoon;Lim, Jin-Oh;Ryu, Ji-Yeon;Oh, Jae-Seon;Woo, Chul-Woong;Nam, Jeung-Hee
    • Journal of radiological science and technology
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    • v.33 no.1
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    • pp.25-29
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    • 2010
  • To evaluate the usefulness of newly designed percutaneous bone biopsy needle for pumpkin's specimen collection. We manufactured three types of biopsy needle with different internal processing which were made of 10 mm-diameter acrylic material. We made the conventional type (Ct) similar to the clinical type then compared the test group. The type a (Ta) made 1 cm-length internal processing from the distal, type b (Tb) made taper, and type c (Tc) made internal processing like spiral configuration. We performed 20 times biopsy to get an 10 mm length specimen from pumpkin's surface and evaluated the success rate of the biopsy, length of the specimen, and determine internal processing type of the most suitable biopsy needle (ANOVA test). Success rates of Ct, Ta, Tb, and Tc were 55%, 80%, 90%, and 100%, respectively. The lengths of the specimen of Ct, Ta, Tb, and Tc were 5.6±1.1mm5.6±1.1mm, 5.9±0.87mm5.9±0.87mm, 3.9±0.77mm3.9±0.77mm, and 9.4±0.54mm9.4±0.54mm, respectively. All groups were statistically significant (p < 0.05) except the group between Ct and Ta (p = 0.28). Newly designed bone biopsy needle seems to be useful for obtaining enough specimen. Tc may be more effective than other types.

Effect of Peel and Whole Crop of Kale and Angelica Keiskei Koidz on Fatty Acid Composition and Quality of Eggs (케일과 명일엽 및 부산물의 급여가 계란 품질 및 지방산 조성에 미치는 영향)

  • Kang, Hwan-Ku;Kang, Geun-Ho;Kim, Dong-Wook;Lee, Sang-Jin;Kim, Sang-Ho
    • Food Science of Animal Resources
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    • v.28 no.5
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    • pp.645-650
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    • 2008
  • The effects of various levels of dietary dried whole crop of kale (0.1%, 0.3%), dried peel of kale (0.3%), dried whole crop of Angelica keiskei (Koidz) (0.1%, 0.3%), and peel of Angelica keiskei (Koidz) (0.3%) in egg-laying performance were studied with 560 ISA brown layers for a period of 12 weeks. No significant differences were recognized between the treatments and control in egg production, feed intake and egg mass. The quality of egg and eggshell were not different among treatments but egg yolk color was improved in the both of whole crop and peel of kale and Angelica keiskei (Koidz). Vitamin and polyunsaturated fatty acid concentration of eggs increased in treatments compared to control but were not significantly different from controls. In conclusion, dried peel of kale and Angelica keiskei (Koidz) supplementation in laying hens diet improved egg yolk color, and improve vitamin concentration of chicken eggs.

Quality characteristics of fermented vinegars using pear (배를 이용한 발효식초의 품질특성)

  • Park, Yeon-Ok
    • Food Science and Preservation
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    • v.23 no.6
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    • pp.778-787
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    • 2016
  • Fermented vinegars using pear was compared according to the appled side materials. Quality characteristics of three kinds of the fermented vinegars (pear vinegar, PV; pear black rice vinegar, PBV; pear mint vinegar, PMV) were investigated, which includes pH, total acidity, colors, the contents of sugar, amino acids, total polyphenol, and total flavonoid, ααdiphenylβpycrylhydrazyl (DPPH) radical scavenging ability, and sensory evaluation. Brown rice vinegar (BRV) was used as a control. The pH and total acidity of the fermented pear vinegars were significantly different showing the range of 3.17~3.43 and 4.01~5.05%, respectively (p<0.05). The sugar contents of PV and PMV were significantly higher than other vinegars (p<0.05). L, a, and b values were the highest in PV, PBV, and PMV, respectively. Among the four vinegars, the essential amino acids were the highest in PV with the order of lysine, isoleucine, valine, and threonine. Besides, the fermented pear vinegars have many non-essential amino acids such as glutamic acid and aspartic acid. The aspartic acid content was the highest in PV while glutamic acid content was the highest in BRV. The total polyphenol content was the highest in PV while total flavonoid content was the highest in PBV. The DPPH radical scavenging ability (%) was the highest in PV. In sensory evaluation, PBV showed the highest color, taste and overall preference scores. These results show that pear would be desirable to prepare high-quality vinegars and functional foods.

Escape from Binary Opposition -Analysis of Performative Method in - (이항대립(二項對立)으로부터의 탈주 -<오목어>에서의 매체 수행 방식 분석-)

  • Suh, Yong-Chu
    • Cartoon and Animation Studies
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    • s.41
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    • pp.511-531
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    • 2015
  • The underlying impetus of the birth of animated film is attraction about a moving image. And the animation image occurs from the process of performative relationship between an animator and apparatus. Therefore, analysing the method how the moving image is constructed will be the focal starting point to deal with an animated film as a text. In this context, that conveys the theme in more sensuous way will be examined in a dimension of the material, technique and image-making method. KIM Jin-man's is a Stop Motion Animated Film with Noodlescreen about a journey of a fish that wishes to go outside of the water. KIM created original and friendly images out of plain thin noodle which is a common ingredient in Korea, and dealt with the ontological introspection based of the concept of Nondualism. Nondualism based on the interconnected and cyclical eastern philosophy which is different from the western dualistic theory points to the idea that the universe and all its multiplicity are ultimately expressions or appearances of one essential reality. This paper focuses on KIM's recent work and sees how Nondualism is applied throughout the animated film by analysing the performative method of mediums, technique, and structure. First of all, the form of Noodlescreen will be reviewed in Chapter Two. Pinscreen Animation which was invented by Alexander Alexeieff and Claire Parker will be also compared with Noodlescreen in the aesthetic viewpoint here. In Chapter Three, it will be analysed how the description of the image of binary opposition itself provides expanded sense and rich metaphor. Lastly, the format of Mise-en-abyme going constantly towards outer space will be dealt how it exposes the cinematic illusion and spatiality in Chapter Four. Throughout the whole chapters, it will reviewed how the concept of Nondualism relates the images of and deactivate the boundary of binary opposition in terms of both the story development and the visualization method. By this methodology, it will be confirmed that image of animated film not only explains the narrative but also activates the perception about the theme and provides integrated sensory experiences in the independent and expanded dimension.

Studies on a Feasibility of Swine Farm Wastewater Treatment using Microbial Fuel Cell (미생물연료전지의 가축분뇨 처리 가능성 연구)

  • Jang, Jae-Kyung;Kim, Se-Hee;Ryou, Young-Sun;Lee, Sung-Hyoun;Kim, Jong-Gu;Kang, Young-Goo;Kim, Young-Hwa;Choi, Jung-Eun
    • Microbiology and Biotechnology Letters
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    • v.38 no.4
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    • pp.461-466
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    • 2010
  • In this study the feasibility of simultaneous electricity generation and treatment of swine farm wastewater using microbial fuel cells (MFCs) was examined. Two single-chamber MFCs containing an anode filled with different ratio of graphite felt and stainless-steel cross strip was used in all tests. The proportion of stainless-steel cross strip to graphite felt in the anode of control microbial fuel cell (CMFC) was higher than that of swine microbial fuel cell (SMFC) to reduce construction costs. SMFCs produced a stable current of 18 mA by swine wastewater with chemical oxygen demand (COD) of 3.167±80mg/L after enriched. The maximum power density and current density of SMFCs were 680mW/m3 and 3,770mA/m3, respectively. In the CMFC, power density and current density was lower than that of SMFC. CODs decreased by the SMFC and CMFC from 3.167±80 to 865±21 and 930±14mg/L, achieving 72.7% and 70.6% COD removal, respectively. The suspended solid (SS) of both fuel cells was also reduced over 99% (4,533±67 to 24.0±6.0mg/L). The concentration of nutritive salts, NH4+, NO3, and PO43, dropped by 65.4%, 57.5%, and 73.7% by the SMFC, respectively. These results were similar with those of CMFC. These results show that the microbial fuel cells using electrode with mix stainless-steel cross strip and graphite felt can treat the swine wastewater simultaneously with an electricity generation from swine wastewater.

An Experimental Study on the Hydration Heat of Concrete Using Phosphate based Inorganic Salt (인산계 무기염을 이용한 콘크리트의 수화 발열 특성에 관한 실험적 연구)

  • Jeong, Seok-Man;Kim, Se-Hwan;Yang, Wan-Hee;Kim, Young-Sun;Ki, Jun-Do;Lee, Gun-Cheol
    • Journal of the Korea Institute of Building Construction
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    • v.20 no.6
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    • pp.489-495
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    • 2020
  • Whereas the control of the hydration heat in mass concrete has been important as the concrete structures enlarge, many conventional strategies show some limitations in their effectiveness and practicality. Therefore, In this study, as a solution of controling the heat of hydration of mass concrete, a method to reduce the heat of hydration by controlling the hardening of cement was examined. The reduction of the hydration heat by the developed Phosphate Inorganic Salt was basically verified in the insulated boxes filled with binder paste or concrete mixture. That is, the effects of the Phosphate Inorganic Salt on the hydration heat, flow or slump, and compressive strength were analyzed in binary and ternary blended cement which is generally used for low heat. As a result, the internal maximum temperature rise induced by the hydration heat was decreased by 9.5~10.6% and 10.1~11.7% for binder paste and concrete mixed with the Phosphate Inorganic Salt, respectively. Besides, the delay of the time corresponding to the peak temperature was apparently observed, which is beneficial to the emission of the internal hydration heat in real structures. The Phosphate Inorganic Salt that was developed and verified by a series of the aforementioned experiments showed better performance than the existing ones in terms of the control of the hydration heat and other performance. It can be used for the purpose of hydration heat of mass concrete in the future.