• Title/Summary/Keyword: Type Specimens

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Structural repairing of damaged reinforced concrete beam-column assemblies with CFRPs

  • Yurdakul, Ozgur;Avsar, Ozgur
    • Structural Engineering and Mechanics
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    • v.54 no.3
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    • pp.521-543
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    • 2015
  • Depending on the damage type as well as the level of damage observed after the earthquake, certain measures should be taken for the damaged buildings. In this study, structural repairing of two different types of damaged RC beam-column assembly by carbon fiber-reinforced polymer sheets is investigated in detail as a member repairing technique. Two types of 1:1 scale test specimens, which represent the exterior RC beam-column connection taken from inflection points of the frame, are utilized. The first specimen is designed according to the current Turkish Earthquake Code, whereas the second one represents a deficient RC beam-column assembly. Both of the specimens were subjected to cyclic quasistatic loading in the laboratory and different levels of structural damage were observed. The first specimen displayed a ductile response with the damage concentrated in the beam. However, in the second specimen, the beam-column joint was severely damaged while the rest of the members did not attain their capacities. Depending on the damage type of the specimens, the damaged members were repaired by CFRP wrapping with different configurations. After testing the repaired specimens, it is found that former capacities of the damaged members were mostly recovered by the application of CFRPs on the damaged members.

Morphological classification of the moderator band and its relationship with the anterior papillary muscle

  • Lee, Ju-Young;Hur, Mi-Sun
    • Anatomy and Cell Biology
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    • v.52 no.1
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    • pp.38-42
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    • 2019
  • This study investigated and classified the various types of moderator band (MB) in relation to the anterior papillary muscle, with the aim of providing anatomical reference information and fundamental knowledge for use when repairing the congenital defects and understanding the conduction system. The study investigated 38 formalin-fixed human hearts of both sexes obtained from donors aged 38-90 years. The MB was evident in 36 of the 38 specimens (94.7%). The morphology of the MB and its connection with the APM took various forms. The MBs that had a distinct shape were classified into three types according to their shape: cylindrical column, long and thin column, and wide and flat column. Types 2 and 3 were the most common, appearing in 15 (41.7%) and 14 (38.9%) of the 36 specimens, respectively, while type 1 was observed in seven specimens (19.4%). Type 3 was divided into subtypes based on their length. The MB usually originated from a single root (91.7%), with the remainder exhibiting double roots. The pairs of roots in the latter cases had different shapes. The originating point of the MB ranged from the supraventricular crest to the apex of the ventricle. The most-common originating point was in the middle (25 of 36 specimens, 69.4%), followed by the upper third (13.9%), the lower third (11.1%), and the top fifth (5.6%) of the interventricular septum. This study has produced fundamental anatomical and clinical information that will be useful when designing cardiac surgical procedures.

A new distribution record of Scutellaria barbata D. Don (Lamiaceae) and an erroneously identified Scutellaria in Korea

  • LEE, Yoonkyung;KIM, Jung-Hyun;LEE, Byoung Yoon;KIM, Jin-Seok;KIM, Sangtae
    • Korean Journal of Plant Taxonomy
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    • v.48 no.2
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    • pp.123-128
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    • 2018
  • Earlier taxonomic studies of Korean Scutellaria reported a new record of Scutellaria hastifolia L. in Korea based on three herbarium sheets. During a reexamination of these specimens, we found that the leaf characters of these specimens differ from those in the type specimen of S. hastifolia. Based on a literature survey and confirmation of the type specimen, the specimens identified as S. hastifolia thus far were a misidentification of S. barbata D. Don. S. hastifolia is clearly different from S. barbata by single conspicuous teeth on both sides of the leaf margins and larger leaves. In addition to the distribution sites of the three specimens used in the previous study, a distribution site of the S. barbata was newly found in the southern part of Korea. In this study, we report a new distribution of S. barbata in Korea, correct a previous report of S. hastifolia, describe the morphological characters of S. barbata, and suggest a taxonomic key to Korean Scutellaria including S. barbata.

Lectotypification of the names Scrophularia alata and S. kakudensis(Scrophulariaceae)

  • Jang, Hyun-Do;Ji, Seong-Jin;Noh, Tae-Kwon;Oh, Hyun-Kyung;Nam, Gi-Heum
    • Journal of Species Research
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    • v.10 no.2
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    • pp.164-167
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    • 2021
  • According to Article 9.3 of the International Code of Nomenclature for algae, fungi, and plants(Shenzhen Code), a lectotype may be selected as the nomenclatural type from the original material, if the name was published without a holotype. While reviewing the genus Scrophularia collected in Northeast Asia, we found that two species, S. alata A. Gray and S. kakudensis Franch., were still untypified. S. alata has three specimens considered as syntypes in two herbaria, Harvard University and the Smithsonian Institution. For S. kakudensis, two specimens considered as syntypes at the Muséum National d'Histoire Naturelle, Paris were classified as normal specimens, not type specimens. Therefore, two species of Scrophularia L. namely, S. alata A. Gray and S. kakudensis Franch., are lectotypified. The lectotypes are kept in the Harvard University and the Muséum National d'Histoire Naturelle, Paris, respectively. Furthermore, some nomenclatural issues related to these names are discussed, and the photographs of the selected lectotypes are provided.

Utilizing vacuum bagging process to enhance bond strength between FRP sheets and concrete

  • Abdelal, Nisrin R.;Irshidat, Mohammad R.
    • Structural Engineering and Mechanics
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    • v.72 no.3
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    • pp.305-312
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    • 2019
  • This paper investigates the effect of utilizing vacuum bagging process to enhance the bond behavior between fiber reinforced polymer (FRP) composites and concrete substrate. Sixty specimens were prepared and tested using double-shear bond test. The effect of various parameters such as vacuum, fiber type, and FRP sheet length and width on the bond strength were investigated. The experimental results revealed that utilizing vacuum leads to improve the bond behavior between FRP composites and concrete. Both the ultimate bond forces and the maximum displacements were enhanced when applying the vacuum which leads to reduction in the amount of FRP materials needed to achieve the required bond strength compared with the un-vacuumed specimens. The efficiency of the enhancement in bond behavior due to vacuum highly depends on the fiber type; using carbon fiber showed higher enhancement in the bond strength compared to the glass fiber when vacuum was applied. On the contrary, specimens with glass fiber showed higher enhancement in the maximum slippage compared to specimens with carbon fibers. Utilizing vacuum does not affect the debonding failure modes but lead to increase in the amount of attached concrete on the surface of the debonded FRP sheet.

Cryptonemia asiatica sp. nov. (Halymeniaceae, Rhodophyta), a new marine macroalgal species from Korea and Japan

  • Yang, Mi Yeon;Kim, Myung Sook
    • Journal of Ecology and Environment
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    • v.37 no.4
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    • pp.387-393
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    • 2014
  • We propose Cryptonemia asiatica sp. nov. from Korea and Japan. We used molecular analyses of plastid-encoded rbcL and morphological observations to resolve the taxonomic identities of C. lactuca from Korea, C. luxurians from Japan, and C. seminervis from Spain. Specimens of C. lactuca and C. luxurians fell within the same molecular phylogenetic clade (with 100% bootstrap support) and were clearly separated from specimens of C. luxurians collected from the type locality in Brazil. Our analyses demonstrated identical molecular sequences between C. seminervis specimens from Spain and C. lomation specimens from France. Morphological characteristics of the new species, C. asiatica include prominent midribs through the mid thallus, a cortex 4-6 cells thick, and a blade with undulate margins. Molecular evidence indicates that specimens from Korea and Japan previously assigned to C. lactuca and C. luxurians, respectively, should be reassigned to Cryptonemia asiatica. Binomial C. luxurians from Brazil should be resurrected as the independent species of Cryptonemia.

A Study on the Handle and Texture of Artificial Suede (인조 스웨이드의 handle 및 질감에 관한 연구)

  • 신경인;김종준
    • Journal of the Korean Society of Clothing and Textiles
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    • v.24 no.1
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    • pp.128-137
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    • 2000
  • A range of suede-like samples were collected including woven fabric type, nonwoven fabric type, and natural suede(sheep). The surface textures of these suede-like fabrics are rather diverse and different from the plain filament type fabrics since there are a lot of fine surface free fiber ends. Physical and mechanical measurements were carried using the KES equipments. Based on the Kawabata-Niwa translational equation, primary hand values and THV were calculated. Uniaxial tensile tests were performed. Using glossmeter, the reflectance pattern was analyzed at different incidence and receiving angles. In order to capture the surface images of the specimens, a CCD camera and frame grabber connected to a PC were employed. The reflectance uniformity of the images was measured with line-profile analysis and standard deviation values of the profile of the images were calculated. After the multiscale wavelet transfermation, correlation among the transformed image was analyzed at each scale. The reflectance uniformity of the natural suede was better than that of nonwoven type suede, while that of woven type suede was the last among the selected three samples(natural suede, nonwoven type, woven type). The correlation analysis among images has shown the possibility of using the wavelet transformation of the images as one of the measures to detect similarities among the textured specimens.

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Study on the Fatigue Test and the Accelerated Life Test for Dental Implant using Universal-Joint Test Type (유니버설조인트 시험방식을 이용한 치과용 임플란트의 피로시험 및 가속수명시험에 관한 연구)

  • Do, Gyeong Hun;Lee, Seok Jin;Kim, Jong Mi;Kim, Sung Min
    • Journal of Applied Reliability
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    • v.17 no.1
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    • pp.50-57
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    • 2017
  • Purpose : This paper is a comparative analysis results of the fatigue test for dental implants and accelerated life test by using a static type loading device commonly used in Korea and a dynamic type loading device (universal-joint) recommended by FDA. Methods : Fatigue tests of dental implant is based on ISO 14801 and classified into static load test and dynamic load test. The tests were carried out on three test specimens by four load stress steps under each loading device. For analysis on failure mode such as crack, fracture and permanent deformation of test specimens, we used X-ray three-dimensional computed tomography on test specimens before and after the fatigue tests. The design of the accelerated life test was based on the analysis results of the fatigue life data obtained from the dynamic load test and the statistical analysis software (Minitab ver.15) was used to analyze the appropriate life distribution. Results : As a result of the fatigue tests and the accelerated life tests at same acceleration condition under each test method, the fatigue life under the dynamic type loading device (universal-joint) was shorter than when static type loading device was applied. Conclusion : This paper can be used as a reference when the universal-joint type loading device for implants fatigue test is applied as ISO 14801.

An Experimental Evaluation on Bond Strength between Porcelain and Recast Allog (도재용(陶材用) 비귀금속(非貴金屬) 합금(合金)의 재사용(再使用)에 따른 결합강도(結合强度)의 실험적(實驗的) 측정(測定))

  • So, Myung-Sub
    • Journal of Technologic Dentistry
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    • v.11 no.1
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    • pp.103-109
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    • 1989
  • Bond strength between alloy and ceramic plays an important role in deciding the quaring the processing of metalceramic restorations. Now the author had an experiment on the measurement of bond strength differences accoding to the contents of recast alloy used during the processing of metal-ceramic restorations. In the experiment, Anusavice's Planar Interface Shear Bond Test was employed to determine the bond strength. Total 25 specimens were divided as 5 groups, that is, 5 specimens in a group respections : Group I (new alloy 100%) Group II (new 75%$\cdot$recast 25%), Group III (new 50%$\cdot$recast 50%), Group IV (new 25%$\cdot$recast 75%), Group V(recast 100%). All specimens examined micropically and respective strength values of the group specimens were checked simultaneously. The results were as follows, 1. In the analtsis of variance the result showed the significant differences of 1%(P<0.01) among the each group classifid according to the recast contents. 2. When the interfaces of specimens were examined with an electron microscope, the air bubble were evenly occurred in all the specimens, and the occurrence frequencies and the sizes of air bubble were different between Group I and Group III, especially marked different Group I and Croup V. 3. In respective verification of each group through T-test, between Group I and Group II, between Group I and Group III did not show significant differences. 4. There was significant difference between Group I and Group IV, between Group I and Group V as 1%(P<0.01). 5. In the Shear Bond Test of all the groups, Croup V showed the lowest value. Explanatoion of Figures Fig 1. Main fracture type of metal-porcelain interlace showed in group I, II, III from shear Bond Test resets. Fig 2. Main fracture type of metal-porcelain interface showed In group Ⅳ, Ⅴ form shear Bond Test resets. Air bubble and their size appeared around interface of metal-porcelain. Fig 3. Group I, Fig 4. Group II Fig 5. Group III, Fig 6. Group IV, Fig 7. Group V.

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Experimental Study on Structural Performance of Recycled Coarse Aggregate Concrete Confined by Steel Spirals (나선철근으로 횡구속된 순환골재 콘크리트의 구조적 성능에 관한 실험적 연구)

  • Kim, Sang Woo;Jung, Chang Kyo;Lee, Sun Hee;Kim, Kil Hee
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.1
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    • pp.103-111
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    • 2011
  • This paper estimated the structural behavior of recycled aggregate concrete confined with spiral reinforcement. The main test parameter was designed to be the type of aggregates and the steel ratio of spirals. A total of 18 specimens were cast and tested in this study. All the specimens had a diameter of 150mm and a height of 300mm. The specimens can be divided into two groups, based on the type of coarse aggregate used. The ratio of spiral reinforcement was varied from 0 % to 1.75%. To measure the axial and lateral deformations of the specimens, a total of six linear variation displacement transducers (LVDTs) were installed at each specimen. Furthermore strain gauges were also attached to the steel spirals to obtain the strain of spiral reinforcements. From the experimental results, the structural performance of recycled aggregate concrete specimens confined by steel spirals was similar to that of natural aggregate concrete specimens regardless of the ratio of spiral reinforcement.