• 한국생산제조학회지
• /
• 제23권5호
• /
• pp.435-442
• /
• 2014

This paper describes an improved design model that can be used to configure a non-contact pneumatic device to turn a large sheet at the in-line system. For rotational moving in the conveyor system, the conventional method is to turn the system itself. The improved non-contact pick-up system mainly uses 8 pairs of L-shaped latches and 12 swirl type heads. It is positioned above the upward air flow table. This system performs the non-contact gripping and side-edge contact support in the vertical and rotational directions to hold the self-weight of a large flat sheet. A non-contact air head can exert a sufficient gripping ability at 4N lower than the standard working pressure. The side latches support 60% of the lifting force required. Through structural and flow analysis, the working conditions were simultaneously considered in accordance with the deflection and flatness of the glass.

• 농업과학연구
• /
• 제19권1호
• /
• pp.28-32
• /
• 1992

태국의 토양으로부터 분리한 젤라틴 분해능을 갖는 광합성세균 T-20주(株)는 직경이 $0.6{\sim}0.7{\mu}m$의 적색 간균으로써, Bacteriochlorophyll a의 흡수극대는 870nm이었고 또한, 퀴논종(種)은 UQ-8을 나타내었다. 유기 화합물로써 citrate, aspirate, glutamate, fractose 등을 이용하였다. 이상의 결과로부터 T-20주는 Bergey's Manual of Systematic Bacteriology(1989)에 기재된 Rhodocyclus gelatinosus와 일치한다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제55권12호
• /
• pp.586-590
• /
• 2006

Dendrimers represent a new class of synthetic macromoleculcs characterized by a regularly branched treelike structure. Multiple branching yields a large number of chain ends that distinguish dendrimers from conventional star-like polymers and microgels. The azobenzene dendrimer is one of the dendrimeric macromolecules that include the azo-group exhibiting a photochromic character. Due to the presence of the charge transfer element of the azo-group and its rod-shaped structure, these compounds are expected to have potential interest in electronics and photoelectronics, especially in nonlinear optics. In the present paper, we give pressure stimulation to organic thin films and detect the induced displacement current. Functional photoisometrization organic molecular the photo-stimulus to organic monomolecular L films and LB films of dendrimer and 8A5H were performed. The 8A5H organic monolayer in case of pressure stimulus occurred that positive course but in case of the photo-stimulus compared positive and negative. It is assumed that generation forms of displacement current were measured when photo-stimulus for impression.

• Computers and Concrete
• /
• 제13권2호
• /
• pp.291-308
• /
• 2014

A nonlinear, three-dimensional finite element analysis was conducted on six intermediate L-shaped spandrel beams using the "ANSYS Civil FEM" program. The beams were constructed and tested in the laboratory under eccentric concentrated load at mid-span to obtain a combined loading case: torsion, bending, and shear. The reinforcement case parameters were as follows: without reinforcement, with longitudinal reinforcement only, and reinforced with steel bars and stirrups. All beams were tested under two different combined loading conditions: T/V = 545 mm (high eccentricity) and T/V = 145 mm (low eccentricity). The failure of the plain beams was brittle, and the addition of longitudinal steel bars increased beam strength, particularly under low eccentricity. Transverse reinforcement significantly affected the strength at high eccentricities, that is, at high torque. A program can predict accurately the behavior of these beams under different reinforcement cases, as well as under different ratios of combined loadings. The ANSYS model accurately predicted the loads and deflections for various types of reinforcements in spandrel beams, and captured the critical crack regions of these beams.

• 마이크로전자및패키징학회지
• /
• 제16권2호
• /
• pp.27-31
• /
• 2009

Sn whiskers can grow from the pure Sn and high Sn-based finish and cause the electrical shorts and failures. Even with the wealth of information on whiskers, we have neither the clear understanding of whisker growth nor methods for its prevention. In this study, the whisker grain roots which connected with intermetallic layer were analyzed by high-resolution transmission electron microscopy (HR-TEM). In the Sn-Cu plated leadframe (LF) that was stored at ambient condition for 540 days, filament-shaped whiskers were grown on the Sn-plated surface and ${\eta}'-Cu_6Sn_5$ precipitates were widely distributed along the grain boundaries at the Sn matrix. The measured of the lattice fringes at the ${\eta}'-Cu_6Sn_5$ was $4.71{\AA}$ at the coarse grain and $2.91{\AA}$ at the fine grain. The $Cu_3Sn$ which generates the tensile stresses was not observed. The formation of $Cu_6Sn_5$ precipitates and intermetallic layer were strongly related to whisker growth, but, the whisker growth tendency does not closely relate with the geometric morphology of irregularly grown intermetallic compound (lMC).

• Animal Systematics, Evolution and Diversity
• /
• 제19권1호
• /
• pp.111-117
• /
• 2003

경기도 시화호와 여수 및 대한해협에서 채집된 히드라해파리류는 관사르스해파리 (Sarsia tubujosa)와 네잎백합해파리 (Liriope tetraphylla)로 각각 동정되었다. 이들은 한국 미기록종으로 판명되어 재기재하여 보고한다. 관사르스해파리는 긴 관모양의 구병과 4개의 촉수를 가진다. 경해파리목 (Trachymedusae)에 속하는 네잎백합해파리는 내산의 중앙 표면에 위치한 삼각형의 생식선과 우산의 4분원 (quadrant)에 7개의 구심맹관 (blind centripetal canals)을 가지며 길고 굵은 구병과 구병 끝에 4개의 주름진 구엽을 가진다. 본 연구의 결과 지금까지 밝혀진 한국 해산 히드라해파리류는 5목 11과 12종이 된다.

• Journal of Microbiology
• /
• 제41권4호
• /
• pp.306-311
• /
• 2003

In Korea, a Lymantria dispar multinucleocapsid nucleopolyhedrovirus, LdMNPV-NM, was isolated and characterized from dead L. dispar larvae. The polyhedra of LdMNPV-NM were irregularly shaped with a diameter of $1.62{\pm}0.33{\mu}m$. Numerous virions comprised of the multinucleocapsid were evident in the electron microscopic examination of the polyhedra cross sections. These polyhedra were composed of a major protein of 30 kDa. The restriction enzyme digestion patterns of LdMNPV-NM showed that this isolate had some different fragments from those of the Gypchek LdMNPV isolate, although their overall profiles were similar. The deduced amino acid sequence of the enhancin gene of LdMNPV-NM showed differences when compared to previously reported enhancin genes of other LdMNPV strains. These results suggested that the LdMNPV-NM isolate from Korea was a new NPV strain and had a new enhancin gene.

• 대한기계학회논문집A
• /
• 제35권9호
• /
• pp.1091-1097
• /
• 2011

SGBEM-FEM 교호법은 유한 물체 내에 존재하는 삼차원 균열을 해석하는 유용한 방법으로 알려져 있다. 이 방법으로 일반적인 평면 혹은 비평면 삼차원 균열에 대한 정확한 응력강도계수를 구할 수 있다. 기존의 방법에서는 균열을 모델화 하는데 8 절점 사각형 경계요소를 사용한다. 그러나 임의 형상의 균열의 경우는 3 절점 삼각형 요소를 사용하여 균열을 모델화 하는 것이 더 편리하다. 따라서 본 논문에서는 3 절점 삼각형 요소와 7 절점 사각형 요소를 사용하여 전진 프런트 법으로 균열을 모델링 하였다. 사용된 균열 모델의 정확성을 검토하기 위하여 몇 가지 형상의 균열에 대하여 응력강도계수를 구하여 기존의 해와 비교하였다.

• 한국소음진동공학회논문집
• /
• 제22권10호
• /
• pp.994-1002
• /
• 2012

Acoustic power transmission loss(TL) is an important performance of the muffler system. TL will be affected by the velocity of the fluid in duct since acoustic pressure varies according to the fluid velocity. In this paper, two kinds of fluid model, potential flow and turbulent flow, for the fluid flowing in simple expansion chamber are considered. The effects of their two fluid models in acoustic TL are investigated for the straight and L-shaped simple expansion chamber. In higher frequency range, the characteristics of TL of the two fluid models show different results. The variation of TL according to the fluid velocity is shown more distinctly when turbulence model is used. Turbulent flow model should be used to obtain better estimation of acoustic TL in higher frequency range.

• Archives of Reconstructive Microsurgery
• /
• 제14권2호
• /
• pp.131-137
• /
• 2005

The extensor digitorum brevis (EDB) muscle island flap is a reliable, safe method for coverage of foot and ankle. There are many variation in approach such as curvilinear, zigzag, L-shaped or vertical longitudinal incision for exposure of the EDB muscle. These approaches use only single incision excluding the distal incision for exposure of the distal tendon. Since dorsalis pedis artery vascular bundle and sinus tarsi branch of the lateral tarsal artery both requires careful dissection, single incision alone may cause not only difficulty in exposure but also skin sloughing at donor site. So we tried to modify the approach into two parallel longitudinal incision, one for dorsalis pedis vascular bundle and the other for sinus tarsi branch exposure. The author treated 9 patient with EDB muscle flap. We used single incision in six patients, and two parallel incision in three patients. All the flap survived. In two parallel incision group, dissection was more easy and rapid. So we would like to suggest that two parallel longitudinal incision approach is better method than the single incision technique for exposure of the EDB muscle flap.