• 제목/요약/키워드: type specimens

검색결과 2,191건 처리시간 0.031초

A considerable review on type specimens of Korean vascular plants in the Herbarium of the Komarov Botanical Institute (LE) Addition

  • Grabovskaya-Borodina, Alisa E.;Illarionova, Irina D.;Jang, Hyun-Do;Lee, Byoungyoon;Suh, Min Hwan;Park, Jeong Mi
    • Journal of Species Research
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    • 제7권1호
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    • pp.73-79
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    • 2018
  • The review provides the information about 46 type specimens on 35 taxa of vascular plants from Korea (Fig. 1), kept in the Herbarium of the Komarov Botanical Institute of the Russian Academy of Sciences in addition to 150 taxa published before. Lectotype of Ligustrum patulum Palib is designated here.

평직유리섬유강화 에폭시 적층판의 기계적 특성 이방성 (Mechanical Properties Anisotropy of Plain Weave Glass Fabric Reinforced Epoxy Resin Laminates)

  • 김연직
    • 한국자동차공학회논문집
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    • 제17권3호
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    • pp.15-21
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    • 2009
  • The anisotropic mechanical properties were measured for the three orthogonal orientations of plain weave glass fabric reinforced epoxy resin laminate. In tensile and flexural tests, axial and edge type specimens failed by pull-out of warp and fill yarns, respectively. In contrast, the thickness type specimens failed by adhesive failure process. Longitudinal cracking occurred in several of the edge type specimens during tensile test. That cracking caused pop-in in the stress-strain curve. Defects induced by improper coupon machining caused that cracking.

돌마자 M. yaluensis (어상강, 잉어과)의 동종이명, Microphysogobio tungtingensis uchidai (Microphysogobio tungtingensis uchidai, a Junior Synonym of M. yaluensis (Pisces, Cyprinidae))

  • Ik-Soo Kim;Hyun Yang
    • Animal Systematics, Evolution and Diversity
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    • 제16권2호
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    • pp.159-163
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    • 2000
  • 1973년 Banarescu and Nalbant는 우리나라 낙동강에서 채집된 모래무지아과의 어류 표본 5개체를 근거로 하여 Microphysogobio tungtingensis uchidai로 기재 발표하고, Uchida가 미확인종으로 보고한 경모치 Microphysogobio sp.를 M. t. uchidai의 동종이명으로 처리하였다. 그러나 Microphysogobio t. uchidai의 type specimens의 모식 표본들의 입술의 유두돌기를 포함한 계수 및 계측 형질을 비교 검토한 결과 M. t. uchidai는 돌마자 M. yaluensis의 동종이명임을 확인하였다. 확인하였다.

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나이트라이드계 세라믹 코팅의 고온 마모, 마찰거동 (High Temperature Tribological Behaviors of Nitride Based Ceramic Coatings)

  • 김장엽;임대순;이상로;백운승
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1996년도 제23회 학술대회
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    • pp.83-86
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    • 1996
  • In this study, CrN, TiN and TiN + CrN coatings have treated onto the steel substrates by ion plating to improve their tribological behaviors. Some of the specimens were ion nitriding treated to study the effect of ion nitriding on wear behavior. The wear tests were performed with these specimens by ball-onplate type and disc-on-plate type wear tester. It was demonstrated that ion nitriding treatment improve wear resistance of the coatings. The results of high temperature wear tests indicated that the specimens coated with CrN were exhibited the better wear resistance properties than the specimens with TiN coatings

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차체구조물에서 면내 굽힘모우멘트 및 과하중이 피로특성과 균열전파 거동에 미치는 영향에 관한 연구 (A Study on the Fatigue Characteristics and the Behavior of Crack Propagation by Overload and Bending Moment in Car Body Structure)

  • 성기찬;장경복;정진우;강성수
    • Journal of Welding and Joining
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    • 제19권6호
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    • pp.652-657
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    • 2001
  • To analyze and predict crack initiation position and propagation directions on the spot welded area are very important for strength design of the automobile body structure. It is necessary to test by method considering random loads with variable amplitude for strength design of vehicle body structure, because driving cars are actually subjected to random loads with variable amplitude in the road. Although this condition, nearly all tests haute been performed under constant load conditions in the laboratory because it is impossible to replay like an actual conditions. In this study, using in-plane bending type specimens, the overload factor affecting on the fatigue strength, crack initiation and propagation directions of spot-welded specimens have been studied.

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Mechanical performance of additively manufactured austenitic 316L stainless steel

  • Kim, Kyu-Tae
    • Nuclear Engineering and Technology
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    • 제54권1호
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    • pp.244-254
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    • 2022
  • For tensile tests, Vickers hardness tests and microstructure tests, plate-type and box-type specimens of austenitic 316L stainless steels were produced by a conventional machining (CM) process as well as two additive manufacturing processes such as direct metal laser sintering (DMLS) and direct metal tooling (DMT). The specimens were irradiated up to a fast neutron fluence of 3.3 × 109 n/cm2 at a neutron irradiation facility. Mechanical performance of the unirradiated and irradiated specimens were investigated at room temperature and 300 ℃, respectively. The tensile strengths of the DMLS, DMT and CM 316L specimens are in descending order but the elongations are in reverse order, regardless of irradiation and temperature. The ratio of Vickers hardness to ultimate tensile strength was derived to be between 3.21 and 4.01. The additive manufacturing processes exhibit suitable mechanical performance, comparing the tensile strengths and elongations of the conventional machining process.

Stress relaxation effect on uniaxial compressive strength values of a silt type soil

  • Eren Komurlu
    • Geomechanics and Engineering
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    • 제32권5호
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    • pp.495-502
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    • 2023
  • In this study, stress relaxation tests were carried out by keeping silt type soil specimens under different strain levels. Decreases in the stress values with time data was collected to better understand the effect of the strain level on the relaxation properties of soil specimens. In addition, the stress relaxation effect on the uniaxial compressive strength (UCS) values of the specimens was investigated with a series of tests. According to the results obtained from this study, the UCS values of the silt specimens significantly vary as a result of the stress relaxation effect. The UCS values were determined to increase with an increase of relaxation strain level to a threshold value. On the other hand, the UCS values were found to be affected adversely in case of high stress levels at the initiation of the relaxation, which are close to the peak level.

아말감의 표면연마에 관한 전기화학적 연구 (AN ELECTROCHEMICAL STUDY ON SURFACE FINISH OF DENTAL AMALGAM)

  • 석창인;엄정문
    • Restorative Dentistry and Endodontics
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    • 제16권2호
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    • pp.18-32
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    • 1991
  • The purpose of this study was to observe characteristic properties of amalgam through the polarization curves and SEM images from 4 type amalgams (Amalcap, Shofu spherical. Dispersalloy and Tytin) with 3 different surface finish procedures (polishing, burnishing and carving) by using the potentiostats (EG & GPARC) and SEM (Jeol JSM-35). After each amalgam alloy and Hg was triturated as the direction of the manufacturer by means of mechanical amalgamator (Samki), the triturated mass was inserted into the cylndrical metal mold which was 12 mm in diameter and 10 mm in height and was pressed with $100kg/cm^2$. 4 specimens of each type amalgam were burnished with egg burnisher and another 4 specimens of each type amalgam were carved with Hollenback carver. Above 8 specimens and remaining untreated 4 specimens were stored at room temperature for about 7 days. Untreated 4 specimens of each type amalgam were polished with abrasive papers (Deer) from #400 to #1200 and finally on the polishing cloth with $0.5{\mu}m$ and $0.06{\mu}m$ $Al_2O_3 $ powder suspended water. Anodic polarization measurements was employed to compare the corrosion behaviours of the amalgams in 0.9% saline solution at $37^{\circ}C$. The open circuit potential was determined after 30 minutes immersion of specimen in electrolyte. The scan rate was 1 mV/sec and the surface area of amalgam exposed to the solution was $0.64cm^2$ for each specimen. All the potentials reported are with respect to a saturated calomel electrode (SCE). SEM images of each specimen were taken after + 800 mV (SCE) polarization. The results were as follows: 1. The corrosion potential of high copper amalgam was more anodic than that of low copper amalgam. 2. The polished amalgam were more resistant to corrosion than any other burnished and carved amalgam. 3. In the case of polishing, current density of high copper amalgam was lower than that of low copper amalgam.

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밴드형 전단보강근으로 보강된 무량판 슬래브 내부접합부의 구조 거동 평가 (Evaluation of Structural Performance of Flat Plate-Column Interior Connections with Folded Bend Shear Reinforcement)

  • 이범식;박성식;박지영;방종대;전명훈;조건희
    • 토지주택연구
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    • 제4권4호
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    • pp.371-382
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    • 2013
  • 불균형 모멘트가 작용하는 무량판 슬래브 내부접합부를 대상으로 폐쇄형 전단보강근으로 보강한 1개 실험체와 밴드형 전단보강근으로 전단보강한 2개의 실험체를 제작하여 구조성능을 평가하였다. 구조성능평가 결과, 구조설계기준(KBC 2009)으로 평가한 불균형모멘트는 실험결과의 95%로 매우 잘 일치하나, 개정 구조설계기준(KCI 2012)으로 산정한 불균형모멘트는 실험결과의 약 60%에 불과하여, 내부접합부의 불균형모멘트를 과대평가하는 것으로 나타났다. 밴드형 전단보강근은 기존 전단보강근과 비교하여 유사한 구조성능을 가지며, 시공성이 우수한 것으로 나타나 중진지역의 무량판구조물 설계 시 적용할 수 있는 것으로 평가되었다.

솔기 유형이 직물의 드레이프성에 미치는 영향 (The Effects of the Seam Type on Fabric Drape)

  • 팽숙경;정수진;추미선
    • 한국의류산업학회지
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    • 제13권3호
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    • pp.418-424
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    • 2011
  • The purpose of this study was to reveal the effects of the seam type on the fabric drape to provide the basic knowledge for proper seam type according to the design of sewing products. Seven kinds of specimens were constructed with seam (no seam, welt seam with over-edged finish, welt seam with bias bound finish, plain seam with over-edged finish, plain seam with bias bound finish, french seam, and flat fell seam) in wrap direction of the fabric. Using a drape measurement system involving two 18 cm diameter supporting disks, and a digital camera, the images of draped specimens were captured and processed. Drape behavior was evaluated in terms of drape coefficient, node number, and drape profile. Significant differences were found in drape coefficient by the seam types. The specimens with french seam and flat fell seam showed higher drape coefficients compared to those with welt seam and plain seam. Node numbers in the drape profiles showed positive correlation with the weight of the specimens, however, no significant differences were observed in node numbers by the seam types. Significant differences were found in the length of the seamed part by the seam types. The specimens with french seam and flat fell seam showed longer length of the seamed part compared to those with welt seam and plain seam. The ratio of the maximum length in the seam direction to the maximum length perpendicular to the seam direction showed significant differences by the seam types.