• Title/Summary/Keyword: bead

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Verification Study on the Treasure #634 of Silla Face-Inlaid Glass Bead: Focusing on the Design and Cultural Symbolic Elements (보물 제634호 신라 인면 상감 유리구슬의 검증 연구: 디자인과 문화 상징요소를 중심으로)

  • Misuk Choi;Hyo Jeong Lee;Youngjoo Na
    • Science of Emotion and Sensibility
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    • v.26 no.4
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    • pp.71-92
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    • 2023
  • This study investigates the symbolism and meaning of the bead design, its relationship with the Silla culture, and the conditions of glass bead manufacturing to verify the theory of Silla's production of Silla face-inlaid glass beads with excellent artistry and technology. The research method includes investigating the design analysis, ancient documents, myths, relics, glass, and metal production techniques. Moreover, Hongshan cultural relics and other cases of inlaid glass beads were collected. There are records in the literature that the people of Makhan, Buyeo and Silla of ancient Korea people considered beads as treasures and used them for accessories. It was confirmed that all the design elements of the bead-patterned hair topknot, golden crown, birds, and flower trees were closely related to the myth of Kim Al-ji of Silla, the oviparous tales and the sacred birds and divine beasts of the north. Moreover, the pattern and arrangements were found to be similar in other Silla relics. The origin of beads and face pendants was Hongsan culture, and a stone cast for beads was discovered in Bukpyo of Gojoseon, the lower-level culture of Hajiajeom. In addition, excavating inlaid glass beads from Sik-ri tombs of Korea and a face-inlaid glass bead from Toganmori tombs in Japan confirms the theory of Silla's production. The fact that the Baekje people of ancient Korea had a glass bead manufacturing office in Japan in the fifth centuries suggests that the Silla people also had a manufacturing plant in Java, Indonesia, because this place was a crossroads of Silla's Sea Silk Road and a source of raw materials and labors with a close relationship to Silla. Therefore, the face-inlaid glass bead was indeed self-made by Silla, who possessed the tradition of bead myths and hair topknot, and the high-level skills such as gold crowns and metal inlays.

Three-dimensional numerical simulation for the prediction of product shape in sheet casting process

  • Chae, Kyung-Sun;Lee, Mi-Hye;Lee, Seong-Jae;Lee, Seung-Jong
    • Korea-Australia Rheology Journal
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    • v.12 no.2
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    • pp.107-117
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    • 2000
  • Prediction of the product shape in sheet casting process is performed from the numerical simulation. A three-dimensional finite element method is used to investigate the flow behavior and to examine the effects of processing conditions on the sheet produced. Effects of inertia, gravity, surface tension and non-Newtonian viscosity on the thickness profile of the sheet are considered since the edge bead and the flow patterns in the chill roll region have great influence on the quality of the products. In the numerical simulation with free surface flows, the spine method is adopted to update the free surface, and the force-free boundary condition is imposed along the take-up plane to avoid severe singularity problems existing at the take-up plane. From the numerical results of steady isothermal flows of a generalized Newtonian fluid, it is shown that the draw ratio plays a major role in predicting the shape of the final sheet produced and the surface tension has considerable effect on the bead thickness ratio and the bead width fraction, while shear-thinning and/or tension-thickening viscosity affect the degree of neck-in.

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Sustained Release of Ibuprofen from Sodium Alginate Beads (알긴산나트륨을 이용한 이부프로펜의 용출지연)

  • Kwon, Sang-Keun;Seo, Seong-Hoon
    • Journal of Pharmaceutical Investigation
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    • v.25 no.2
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    • pp.153-161
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    • 1995
  • Alginic acid is a hydrophilic , colloidal polysaccharide obtained from cell wall of seaweed or brown algae and has a broad range of applications. Alginlc acid becomes alginate gel bead due to its cation-induced gelation. Dried alginate beads can be reswollen according to environmental pH. The purpose of this paper is to explore the possible applicability of alginate beads as an oral controlled release system of ibuprofen. In this experiment ibuprofen was incorporated in alginate beads and alginate beads were treated with various methods. Ibuprofen release from alginate beads in phosphate buffer (pH 7.4) was laster than in distilled water and dilute HCl. The release of ibuprofen was more sustained in bead than simple mixture and coprecipitate of ibuprofen and sodium alginate. The dissolution rate of ibuprofen was decreased in using of bead that hardened with formaldehyde. The dissolution rate of the drug from the bead was the fastest in 12 hour dried beads, 1.5%-sodium alginate concentration and 1%-calcium chloride concentration. Sodium alginate bead can be used as a sustaind release drug delivery system of water-insoluble drugs.

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A Study on the Back Bead control by Using Short Circuit Frequency in GMA Welding of Sheet Metal (박판 GMA 용접에서 단락 주파수를 이용한 이면비드의 제어에 관한 연구)

  • 안재현;김재웅
    • Journal of Welding and Joining
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    • v.13 no.4
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    • pp.75-84
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    • 1995
  • In GMA welding of sheet metal, the short circuit metal transfer mdoe is preferred because of its low heat input and capability of bridging the root gap. The molten electrode is transferred to the workpiece during repectitive short circuit in the model. The waveform of welding current or voltage and the frequency of short circuiting are affected by a number of factors including: magnitude of welding current and voltage, root gap, electrode extension, power supply characteristics, and so on. In this study experimental models were proposed, which are able to determine the relationship between the root gap and short circuit frequency and the relationship between the root gap and appropriate welding speed that produces the good quality of back bead without burn through. Using the experimental models, the root gap can be obtained from measuring the short circuit frequency, and then the appropriate weldig speed to the root gap can be determined. Thus a back bead control system was constructed by controlling the welding speed for maintaining the quality of back bead. The developed system has shown the successful capability of back bead control.

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Temperature Reduction of Concrete Pavement Using Glass Bead Materials

  • Pancar, Erhan Burak;Akpinar, Muhammet Vefa
    • International Journal of Concrete Structures and Materials
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    • v.10 no.1
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    • pp.39-46
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    • 2016
  • In this study, different proportions of glass beads used for road marking were added into the concrete samples to reduce the temperature gradient through the concrete pavement thickness. It is well known that decreasing the temperature gradient reduces the risk of thermal cracking and increases the service life of concrete pavement. The extent of alkali-silica reaction (ASR) produced with partial replacement of fine aggregate by glass bead was investigated and compressive strength of concrete samples with different proportion of glass bead in their mix designs were measured in this study. Ideal results were obtained with less than 0.850 mm diameter size glass beads were used (19 % by total weight of aggregate) for C30/37 class concrete. Top and bottom surface temperatures of two different C30/37 strength class concrete slabs with and without glass beads were measured. It was identified that, using glass bead in concrete mix design, reduces the temperature differences between top and bottom surfaces of concrete pavement. The study presented herein provides important results on the necessity of regulating concrete road mix design specifications according to regions and climates to reduce the temperature gradient values which are very important in concrete road design.

A Study of the Application of Neural Network for the Prediction of Top-bead Height (표면 비드높이 예측을 위한 최적의 신경회로망의 적용에 관한 연구)

  • Son, J.S.;Kim, I.S.;Park, C.E.;Kim, I.J.;Kim, H.H.;Seo, J.H.;Shim, J.Y.
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.16 no.4
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    • pp.87-92
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    • 2007
  • The full automation welding has not yet been achieved partly because the mathematical model for the process parameters of a given welding task is not fully understood and quantified. Several mathematical models to control welding quality, productivity, microstructure and weld properties in arc welding processes have been studied. However, it is not an easy task to apply them to the various practical situations because the relationship between the process parameters and the bead geometry is non-linear and also they are usually dependent on the specific experimental results. Practically, it is difficult, but important to know how to establish a mathematical model that can predict the result of the actual welding process and how to select the optimum welding condition under a certain constraint. In this paper, an attempt has been made to develop an neural network model to predict the weld top-bead height as a function of key process parameters in the welding. and to compare the developed models using three different training algorithms in order to select an adequate neural network model for prediction of top-bead height.

The characteristic of strength weld according to patterns of weld bead on $CO_2$ laser welding ($CO_2$ 레이저 용접시 비드패턴에 따른 용접강도 특성)

  • Kim, T.I.;Song, Y.C.;Lee, M.Y.;Nam, K.W.
    • Laser Solutions
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    • v.11 no.1
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    • pp.32-35
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    • 2008
  • In the remote welding system using $CO_2$ laser, laser beam can be rapidly transferred to a workpiece by moving mirrors of scanner system. So, it makes reducing the cycle time of welding process. We can also use and apply various patterns of weld beads by linear controlled mirrors. But most of the domestic car makers have usually applied use stitch-shaped weld bead. In that case, we don't have the merit of remote welding system efficiently. Therefore, in this paper, we investigated the characteristic of weld strength according to patterns of weld bead on $CO_2$ laser welding. And we also studied the relationship between shape of weld bead and value of tensile load.

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Effects of the Bead Shape on the Nonlinear Behavior of Cylinder Head Gasket (비드 형상에 따른 실린더 헤드 가스켓의 비선형 거동 특성)

  • Byun, Chul-Jin;Yoo, Seung-Hyun;Yoon, Cheon-Han;Park, Jong-Kuk
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.321-325
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    • 2000
  • Gasket of vehicle engine maintains airtight between cylinder head and engine block under high temperature and pressure, and plays important role in heat conduction of engine. And the characterization of the nonlinear behavior of metal gasket fer various bead shapes is very important as basic research for estimation of gasket durability. But it is very difficult to analyze the behavior of gasket In real experiment. In this paper, to analysis effects of the bead shape on the nonlinear behavior of cylinder head gasket under uniform pressure, the virtual experiment using the nonlinear finite element method was performed. Results are analyzed with residual deformation and the sealing pressure. With the increase of the height and the width of bead, the residual deformation and the sealing pressure increase. And if the height is very high and the width is very narrow, the wrinkles are occurred in the gasket while working.

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Control of molten pool by physical force of bead former in TIG welding of overhead and inclined-up position (위보기 및 경사상진자세의 TIG용접에서 비드성형기의 물리적 힘에 의한 용융지 제어)

  • Ha, Jong-Moon;Ham, Hyo-Sik;Im, Sung-Bin;Seo, Ji-Suk;Cho, Sang-Myung
    • Proceedings of the KWS Conference
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    • 2009.11a
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    • pp.23-23
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    • 2009
  • 우수한 용접부 품질 때문에 TIG를 이용한 오비탈 용접은 파이프 용접에 널리 사용되고 있다. 하지만 루트갭이 없고 루트페이스가 큰 맞대기 오비탈 용접의 위보기 및 경사상진자세에서는 오목한 이면비드가 형성되기 쉽지만, 이러한 문제를 극복하기 위한 연구는 희박한 실정이다. 본 연구에서는 위보기 및 경사상진자세에서 볼록한 이면비드의 형성을 연구하기위해서 용융지의 제어 방법을 적극적으로 검토하였다. 4mm 두께의 SS400 시편을 위보기 및 경사상진자세에서 각각 Bead-on-plate 용접하고, 이 때 비드성형기의 사용에 따른 비드 형상 변화를 관찰하였다. 텅스텐 전극과 비드 성형기간의 거리(Tip To Former Distance, 이하 TTFD)를 4.5mm에서 7.5mm로 1mm단위로 변경시켜 실험하였으며, TTFD가 증가할수록 위보기 및 경사상진자세에서 이면비드 높이가 감소하였으며 표면비드의 처짐이 증가하였다.

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Friction stir welding with back-bead to improve fatigue strength (이면비드를 가진 마찰교반용접에 대한 피로강도에 관한 연구)

  • Rajesh, S.R.;Yun, Byeong-Hyeon;Kim, Heung-Ju;Kim, Teuk-Gi;Cheon, Chang-Geun;Jang, Ung-Seong
    • Proceedings of the KWS Conference
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    • 2007.11a
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    • pp.17-19
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    • 2007
  • The fatigue experiments of friction stir welded Al-6061-T6 alloy with and with out back bead were performed to investigate the variation in fatigue strength and life of the Joint. It was found that there were always existed flaws at the roots of friction stir welds for the normal welding parameters and clamping conditions. In order to overcome this root flaws, friction stir welds with optimum back bead has been developed. The test results with root flaws and with back bead were compared. The fatigue life of weld with root flaws was 5-10 times shorter than that of the friction stir weld with back bead.

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