• Title/Summary/Keyword: 부착력 측정

Search Result 259, Processing Time 0.03 seconds

Evaluation of Durability and Slope Stability of Green Soil using Cementitious Materials (시멘트 계 재료를 사용한 녹생토의 내구성 및 사면 안정성 평가)

  • Kim, Il-Sun;Choi, Yoon-Suk;Yang, Eun-Ik
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.5
    • /
    • pp.45-53
    • /
    • 2018
  • Among the various slope stabilization methods, the green soil method based on the growth of plants is advantageous to the environment, but the durability and slope stability are insufficient when the green soil method is applied to a steep slope and rock slope sites. Therefore, in this study, green soil, which improved the adhesion performance and the vegetation environment, was developed using cementitious materials and ECG, and the durability and slope stability as well as the possibility of its use as a rock vegetation base material were assessed. From the results, the adhesive force and internal friction angle were higher than that of the existing green soil so that it could be used for in situ construction. The soil hardness value was 26 mm, which was slightly higher than that of the best growth condition of the plant, 18~23 mm, and the drying shrinkage strain was approximately 3%; hence, it is not expected to affect the durability of green soil. The results of a rainfall intensity simulation for evaluating the slope adhesion force showed that slope failure did not occur under all conditions. The damage decreased with increasing slope angle. Therefore, the green soils developed in this study have excellent durability and slope stability and can be used for rock slope sites.

Formation and Properties of Gel from Maize Starches with Different Amylose Content (아밀로오스 함량이 다른 옥수수 전분의 겔 형성과 특성)

  • 문세훈;김완수;신말식
    • Korean journal of food and cookery science
    • /
    • v.13 no.4
    • /
    • pp.379-383
    • /
    • 1997
  • To study the effect of amylose on the mechanism of gel formation, swelling power, water solubility, the pattern of alkali gelatinization and gel properties were investigated. The swelling power of waxy maize starch (Amioca) was the highest and followed by those of PFP > Amaizo > Amylomaize VII. Amioca showed higher iodine affinity of soluble amylose than other maize starches. The apparent viscosity of alkali gelatinization measured by Brookfield viscometer for Amaizo was 70${\times}$10$^3$cp which was higher than Amylomaize VII. The apparent viscosity of PFP was increased to 70${\times}$10$^3$cp and then decreased. As maize starches were autoclaved at 121$^{\circ}C$ with starch: water ratio (1 : 9) and autoclaving-cooling cycle were up to 4 times, gel properties were measured by rheometer. Amaizo showed the highest value for hardness, adhesiveness, springiness, and cohesiveness, and hardness of gel after two cycles of autoclaving-cooling was the highest. Gel properties seemed to be affected by the chain length of amylose rather than the content of amylose.

  • PDF

A System Prototype for Remote Haptic Communication (원격 촉감 커뮤니케이션을 위한 시스템 프로토타입)

  • Cha, Jong-Eun;Lee, Jun-Hun;Ryu, Je-Ha
    • 한국HCI학회:학술대회논문집
    • /
    • 2006.02a
    • /
    • pp.238-243
    • /
    • 2006
  • 최근에는 통신기술과 인터넷의 발달로 원격의 사람과 전화, 이메일, 메신저 또는 화상회의 시스템 등을 통해서 쉽게 의사소통 할 수 있다. 이 시스템들은 주로 음성, 그림, 동영상 또는 문자 기반의 시청각 정보를 서로 주고 받으며 자신의 의사 및 감정을 전달하는 통로를 제공한다. 그러나 일상 생활에서 시청각 정보 외에 촉감 정보도 서로 의사소통 하는데 중요한 역할을 한다. 악수, 포옹 등의 촉감 상호작용은 사람 사이에서 친근감을 표시하는데 가장 직접적인 방법으로 자신의 감정을 전달하거나 느낌을 표현하는데 사용된다. 그럼에도 불구하고 촉감 상호작용을 가능케 하는 의사소통 시스템의 연구는 아직 폭넓게 진행되고 있지 않다. 본 논문에서는 일상에서와 같이 원격에서도 상대를 바라 볼 수 있고 자연스럽게 접촉할 수 있는 원격 촉감 커뮤니케이션 시스템을 제안한다. 이 시스템에서는 로컬 사용자가 손가락으로 상대의 몸 특정 부위를 만질 수 있고 서로 그 촉감을 실시간으로 느낄 수 있다. 이 시스템은 크게 AR 시스템, 그래픽 시스템, 햅틱 시스템, 택타일 시스템의 부시스템들로 나눌 수 있다. AR 시스템에서는 몸의 한 부위에 사각형의 AR 마커를 부착한 원격 사용자를 웹카메라로 촬영하고 ARToolKit 을 사용하여 마커의 위치를 측정한다. AR 마커의 바로 밑에는 택타일 장치가 장착되어 있으며 이 부위를 통하여 원격의 사용자는 로컬사용자가 자신의 팔을 만지는 느낌을 받게된다. 그래픽 시스템은 로컬사용자에게 촬영된 원격 사용자와 측정된 마커의 위치가 대표하는 원격 사용자의 가상 피부, 그리고 자신의 가상 손가락을 보여준다. 햅틱 시스템에서는 촉감 장치를 사용하여 로컬 사용자의 손가락 위치를 구하여 원격 사용자의 가상 피부와 접촉했을 때 그 충돌을 감지하고 접촉력을 계산하여 촉감 장치에 반영함으로써 그 접촉력을 느낄 수 있도록 한다. 택타일 시스템에서는 원격 사용자의 AR 마커 밑에 장착된 배열 타입의 진동 촉감 장치에 접촉 정보를 주어 로컬 사용자와 접촉 했을 때 접촉 부위에 진동을 줌으로써 촉감을 느끼도록 한다.

  • PDF

Formation and Properties of Gel from Maize Starches with Different Amylose Content (아밀로오스 함량이 다른 옥수수 전분의 겔 형성과 특성)

  • 문세훈;신말식
    • Proceedings of the SOHE Conference
    • /
    • 1997.12a
    • /
    • pp.45-49
    • /
    • 1997
  • To study the effect of amylose on the mechanism of gel formation, swelling power, water solubility, the pattern of alkali gelatinization and gel properties were investigated. The swelling power of waxy maize starch(Amioca) was the highest and followed by those of PFP >Amaizo > Amylomaize Ⅶ. Amioca showed higher iodine affinity of soluble amylose than other maize starches. The apparent viscosity of alkali gelatinization measured by Brookfield viscometer for Amaizo was $70{\pm}10^3cp$ which was higher than Amylomaize VII. The apparent viscosity of PFP was increased to $70{\pm}10^3cp$ and then decreased. As maize starches were autoclaved at $121^{\circ}C$ with starch : water ratio (1:9) and autoclaving-cooling cycle were up to 4 times, gel properties were measured by rheometer. Amaizo showed the highest value for hardness, adhesiveness, springiness, cohesiveness, and hardness of gel after two times of autoclaving-cooling cycles was the highest. Gel properties was thus affected by the chain length of amylose rather than amylose content.

  • PDF

Reliability of Infrared Thermographic Imaging in the Orofacial Region (구강안면부에서 적외선 체열검사의 신뢰도에 관한 연구)

  • Han, Dong-Joon;Kim, Ki-Suk
    • Journal of Oral Medicine and Pain
    • /
    • v.26 no.4
    • /
    • pp.355-367
    • /
    • 2001
  • 치의학 분야에서 디지탈 근적외선 체열측정 장치(digital infrared thermographic imaging; DITI)의 응용이 미미한 것은 과거 열측정장치의 기술력이 부족한 것이 주된 요인이었다. 그러나 최근들어 기술이 진보함에 따라 실시간 열영상을 재현할 수 있게 되었고 이는 치의학 및 의학계에 많은 관심을 일으키고 있다. 지금까지의 연구를 보면 두개하악장애시 구강영역의 온도변화의 임상적 효용 가능성을 제시하였으나 안면 및 두경부에 대한 실제 기기 및 측정방법의 신뢰도에 대한 연구는 이루어지지 못한 상태이다. 본 연구에서는 DITI에 대한 신뢰도를 조사하였다. DITI의 모니터 상에서 비활동성 발통점의 부위를 찾아내기가 쉽지 않다. 따라서 모니터상에서 안면발통점(joint, temporalis anterior, masseter anterior, masseter inferior)의 부위를 찾아 온도를 찾아내는 방법과 미리 발통점 피부상에 링모양의 마크를 부착하여 모니터상에서 쉽게 찾아내는 방법을 사용하여 신뢰도를 조사하여 비교한 결과 다음과 같다. 1. 조사한 발통점 중에서 temporalis anterior, joint, masseter anterior과 masseter inferior의 순서로 피부온도가 유의하게 온도가 높았으나(p<0.05) masseter 내에서는 유의한 차이를 보여주지 않았다. 2. 4개의 발통점 모두에서 높은 열적 대칭성을 보였으며, 좌우 온도차이는 $0.1^{\circ}C$미만이었다. 3. 다른 시기에 조사한 조사자내 신뢰도는 두 조사자 모두 높은 상관관계를 보여주지 않았으며 대조군과 마크를 사용한 군간에는 뚜렷한 차이를 볼 수 없었다. 4. 동일한 시기에 조사한 조사자간 신뢰도는 두 시기 모두 joint 부위의 일부를 제외하고 높은 상관관계를 보여주었으며, 마크를 사용한 경우 사용하지 않은 경우 보다 훨씬 신뢰도가 높은 상관관계를 나타내었다. 이상의 결과로 보아 DITI는 두개하악장애환자에 대한 두경부 발통점의 온도변화를 측정하는 데 있어 시간에 따른 신뢰도는 결여되었으나 동일 시기의 측정에는 매우 유익할 것으로 사료되며, 특히 발통점에 대한 표시를 사용하는 경우 매우 정확한 온도를 조사할 수 있을 것으로 판단된다.

  • PDF

A Study on Quality Characteristics of Noodle with Whey Powder (유청분말 첨가 국수의 품질 특성)

  • 김선경;유양자
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.11 no.5
    • /
    • pp.386-392
    • /
    • 2001
  • Quality characteristics of conventional and whey noodles were investigated by studying the textural properties. cooking properties, and sensory characteristics. The whey noodles were prepared by mixing whey powder with the wheat flour before noodle production, with the mixture ratio ranging between 1 and 7% in volume. The results are summarized as follows : the addition of whey powder noticeably improved the textural characteristics of the cooked noodles, i.e. hardness, gumminess, and chewiness. The best results were obtained using the following percentage of whey in the mixture: the hardness with 1% added, the gumminess and chewiness with 3% added, and the elasticity with a 7% addiction. The tension force also increased with addition of whey powder, The highest tension force was obtained when 3% of the whey was mixed. While the cooking water of the general noodles displayed a light reddish tint, the cooking water of the whey noodles had a yellow-greenish tint. The cooking water of the whey noodles was more turbid than that of the conventional noodles. The whey noodles increased in volume more than the conventional noodles. after cooking. There was no difference in weight increase and water absorption rates between both types of noodles. More favorable results were shown for appearance, color, texture, and sensory acceptability in the whey noodle than in the conventional noodles.

  • PDF

Effects of Blueberry on the Quality Characteristics of Strawberry Jam (블루베리를 첨가한 딸기잼의 품질 특성)

  • Han, B.K.;Kang, C.S.
    • Journal of Practical Agriculture & Fisheries Research
    • /
    • v.21 no.2
    • /
    • pp.15-25
    • /
    • 2019
  • The effect of blueberries on the quality characteristics of strawberry jam substituted with 50% sugar, glucose syrup 10% was investigated. Strawberry jams with 5, 10 and 20% blueberries in place of strawberry were prepared and evaluated for moisture content, reducing sugar, total acidity, pH, color, total sugar (°Brix), pectin content, anthocyanin content, DPPH radical scavenging activity, texture analysis and sensory characteristics. As the amount of blueberries increased, total acidity, °Brix , reducing sugar content and anthocyanin content of jams increased, while pH decreased, moisture content has changed little. The DPPH radical scavenging activities of the 80% methanol extract from jams were 75.33%, 85.75%, 91.23% and 92.73% at a concentration of 8 mg/mL. Radical scavenging activity increased with the added concentration of blueberries. The lightness decreased with addition of blueberries, but the redness and yellowness increased. The sensory scores for jams increased with the increase of blueberry content; however, strawberry jams with 10% blueberries showed the best scores.

A STUDY ON THE RELATIVE SHEAR BOND STRENGTHS OF SOME ADHESIVE RESTORATIVE MATERIALS TO PRIMARY ENAMEL AND DENTIN (수종 접착성 수복재의 유치 법랑질과 상아질에 대한 상대적 접착력의 비교연구)

  • Kim, Seung-Mee;Kim, Shin;Jeong, Tae-Sung
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.27 no.2
    • /
    • pp.237-245
    • /
    • 2000
  • For the purpose of comparing the bond strengths of some tooth adhesive restoration materials on primary enamel and dentin, 4 kinds (7 brands) of restorative materials including a composite resin (Z 100), a conventional glass ionomer cement (Chem-Flex), 2 brands of resin-modified glass ionomer cements (Fuji II LC-I, Vitremer), and 3 brands of compomers(Dyract AP, F2000, Compoglass) were investigated using UTM for measuring the shear bond strengths. Additionally the failure modes were examined by histologically observing the fractured surfaces of each specimen. The following results were obtained. 1. The shear bond strengths of Z 100 to the primary enamel were higher than those of other experimental materials except Fuji II LC-I, which showed significantly higher bond strength than Chem-Flex or Vitremer (P<0.05). 2. The shear bond strengths of Z 100 to the primary dentin were higher than those of other experimental materials except Dyract AP and Fuji II LC-I, both of which showed significantly higher shear strength than Chem-Flex or Vitremer (P<0.05). 3. The shear bond strengths of all restorative materials except Dyract AP showed relatively higher values to enamel surface than to dentin surface. In Dyract AP, the reverse was true significantly. 4. All materials examined showed cohesive failures except some Chem-Flex and Vitremer, which showed adhesive failures.

  • PDF

The Effect of Surface Tension on Shear Wave Velocities according to Changes of Temperature and Degree of Saturation (온도와 포화도의 변화에 의한 표면장력이 전단파 속도에 미치는 영향)

  • Park, Jung-Hee;Kang, Min-Gu;Seo, Sun-Young;Lee, Jong-Sub
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.32 no.6C
    • /
    • pp.285-293
    • /
    • 2012
  • The surface tension, which is generated in the unsaturated soils, increases the stiffness of the soils. The objective of this study is to estimate the effect of the surface tension, which varies according to the temperature, on the shear wave velocity. Nine specimens, which have the different degree of saturation (0%, 2.5%, 5%, 10%, 20%, 40%, 60%, 80%, 100%), are prepared by using sand-silt mixtures. Experiments are carried out in a nylon cell designed for the measurement of shear waves. A pair of bender elements, which are used for the generation and detection of shear waves, is installed as a cross-hole type. The shear waves are continuously monitored and measured as the temperature of specimens decreases from $15^{\circ}C$ to $1^{\circ}C$. The results show that shear wave velocities of the fully saturated and fully dried specimens change a little bit as the temperatures of specimens decrease. However, the shear wave velocities of the specimens with the degree of saturations of 2.5%, 5%, 10%, 20%, 40%, 60% and 80% continuously increase as temperature decreases from $15^{\circ}C$ to $1^{\circ}C$. Furthermore, a fully saturated specimen is dried at the temperature of $70^{\circ}C$ in order to observe the shear waves according to degree of saturation. The shear wave velocities measured at the temperature of $70^{\circ}C$ are generally lower than those measured at temperature of $15^{\circ}C$. This study demonstrates that the dependence of shear wave velocities on the temperature according to the degree of saturation should be taken into account in both laboratory and field tests.

A Study on the Group Effect of the Inclined Ground Anchor (경사 지반앵커의 군효과에 대한 연구)

  • 임종철;홍석우
    • Geotechnical Engineering
    • /
    • v.10 no.4
    • /
    • pp.39-52
    • /
    • 1994
  • The group effect of inclined ground anchor should be considered in design, but it has been hardly studied due to the difficulties of experimental or theoretical study. In this study, the model tests for the inclined ground anchors are made, and the displacements and strain fields of ground around anchor surface are analysed. As the results of this study, the group effect of the inclined ground anchor in air dried sand ground does not show even though two anchor surfaces are very close(10.7cm, surface to surface). That is to say, ,in the case that the final failure surface by pullout of anchor shows on the anchor surface, the pullout resistances of single anchors are almost same as those of the group anchors in these model tests.

  • PDF