• Title/Summary/Keyword: Number of layers

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Cyclic loading response of footing on multilayered rubber-soil mixtures

  • Tafreshi, S.N. Moghaddas;Darabi, N. Joz;Dawson, A.R.
    • Geomechanics and Engineering
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    • v.14 no.2
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    • pp.115-129
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    • 2018
  • This paper presents a set of results of plate load tests that imposed incremental cyclic loading to a sandy soil bed containing multiple layers of granulated rubber-soil mixture (RSM) at large model scale. Loading and unloading cycles were applied with amplitudes incrementally increasing from 140 to 700 kPa in five steps. A thickness of the RSM layer of approximately 0.4 times the footing diameter was found to deliver the minimum total and residual settlements, irrespective of the level of applied cyclic load. Both the total and residual settlements decrease with increase in the number of RSM layers, regardless of the level of applied cyclic load, but the rate of reduction in both settlements reduces with increase in the number of RSM layers. When the thickness of the RSM layer is smaller, or larger, settlements increase and, at large thicknesses may even exceed those of untreated soil. Layers of the RSM reduced the vertical stress transferred through the foundation depth by distributing the load over a wider area. With the inclusion of RSM layers, the coefficient of elastic uniform compression decreases by a factor of around 3-4. A softer response was obtained when more RSM layers were included beneath the footing damping capacity improves appreciably when the sand bed incorporates RSM layers. Numerical modeling using "FLAC-3D" confirms that multiple RSM layers will improve the performance of a foundation under heavy loading.

Effect of Number of Film Layers and Storage Duration and on the Fermentation Quality of Whole Crop Oat Silage (귀리 사일리지의 비닐겹수 및 저장기간에 따른 발효품질)

  • Song, Tae-Hwa;Park, Jong-Ho;Yoon, Chang;Kang, Chon-Sik;Son, Jae-Han;Yoon, Young-mi;Kim, Yang-Kil;Cheong, Young-Keun;Park, Tae-Il
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.38 no.1
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    • pp.1-6
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    • 2018
  • This study was conducted to investigate the feed value and silage quality according to storage period and film layers in whole crop oat silage. The crude protein content was increased in all silage during the storage periods compared to those before silage, under prolonged storage period slightly and the number of film layers of silage, six layer were higher than four layers, but no significant. NDF and ADF contents were also increased in all silage of storage duration compared to those before silage, but they was similar level between storage duration and number of film layers. TDN content was decreased of the storage duration. However, it was similar under the storage duration and the number of film layers. The pH value was decreased during prolonged storage period and six layers was lower than four layers depending on the film layers. In the organic acid contents, lactic acid and acetic acid were increased under the prolonged storage duration, and butyric acid was higher significantly(p<0.05), six layers of the film were showed higher lactic acid and lower butyric acid(p<0.05). Therefore, oat silage should be used within 6 months it was when treated with 4 layers, if considering the long-term storage, it is desirable to treat it with 6 layers or more.

Influence of temperature on the beams behavior strengthened by bonded composite plates

  • Bouazza, Mokhtar;Antar, Kamel;Amara, Khaled;Benyoucef, Samir;Bedia, El Abbes Adda
    • Geomechanics and Engineering
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    • v.18 no.5
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    • pp.555-566
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    • 2019
  • The purpose of this paper is to investigate the thermal effects on the behaviour reinforced-concrete beams strengthened by bonded angle-ply laminated composites laminates plate $[{\pm}{\theta}n/90m]_S$. Effects of number of $90^{\circ}$ layers and number of ${\pm}{\theta}$ layers on the distributions of interfacial stress in concrete beams reinforced with composite plates have also been studied. The present results represent a simple theoretical model to estimate shear and normal stresses. The effects the temperature, mechanical properties of the fibre orientation angle of the outer layers, the number of cross-ply layers, plate length of the strengthened beam region and adhesive layer thickness on the interfacial shear and normal stresses are investigated and discussed.

Static analysis of a multilayer piezoelectric actuator with bonding layers and electrodes

  • Xiang, H.J.;Shi, Z.F.
    • Smart Structures and Systems
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    • v.5 no.5
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    • pp.547-564
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    • 2009
  • Based on the theory of piezoelasticity, an analytical solution for a typical multilayer piezoelectric composite cantilever is obtained by the Airy function method. The piezoelectric cantilever may consist of any number of layers. Moreover, the material and thickness for different layers may be different. The solution obtained in the present paper is concise and can be easily applied for the bending analysis of multilayer piezoelectric actuators considering the effect of bonding layers and electrodes. At last, a comprehensive parametric study is conducted to show the influence of electromechanical coupling (EMC), the number of piezoelectric layers, the elastic modulus of elastic layer and the thickness ratio on the bending behavior of actuators. Some interesting results for the design of multilayer piezoelectric actuators are presented.

Theoretical Analysis of FBARs Filters with Bragg Reflector Layers and Membrane Layer (브래그 반사층 구조와 멤브레인 구조의 체적 탄성파 공진기 필터의 이론적 분석)

  • Jo, Mun-Gi;Yun, Yeong-Seop
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.39 no.4
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    • pp.41-54
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    • 2002
  • In this study, we have analyzed the effects of the membrane layer and the bragg reflector layers on the resonance characteristics through comparing the characteristics of the membrane type FBAR (Film Bulk Acoustic Wave Resonator) and the one type bragg reflector layers with those of the ideal FBAR with top and bottom electrode contacting air by using equivalent circuit technique. It is assumed that ZnO is used for piezoelectric film, $SiO_2$ are used for membrane layer and low acoustic impedance layer, W are used for the high acoustic reflector layer and Al is used for the electrode. Each layer is considered to have a acoustic propagation loss. ABCD parameters are picked out and input impedance is calculated by converting 1-port equivalent circuit to simplified equivalent circuit that ABCD parameters are picked out possible. From the variation of resonance frequency due to the change of thickness of electrode layers, reflector layers and membrane layer it is confirmed that membrane layer and the reflector layer just under the electrode have the greatest effect on the variation of resonance frequency. From the variation of resonance properties, K and electrical Q with the number of layers, K is not much affected by the number of layers but electrical Q increases with the number of layers when the number of layers is less than seven. The electrical Q is saturated when the number of layers is large than six. The electrical Q is dependent of mechanical Q of reflector layers and membrane layer. Both ladder filter and SCF (Stacked Crystal Filters) show higher insertion loss and out-of-band rejection with the increase of the number of resonators. The insertion loss decreases with the increase of the number of reflector layers but the bandwidth is not much affected by the number of reflector layers. Ladder Filter and SCF with membrane layer show the spurious response due to spurious resonance properties. Ladder filter shows better skirt-selectivity characteristics in bandwidth but SCF shows better characteristics in insertion loss.

Properties of the Puff Pastry with the Pastry Margarine Content and the Number of Layers (Pastry 마가린 함량과 적층 수에 따른 puff pastry 제조 특성)

  • Han, Jang-Ho;Kim, Seok-Young;Yoon, Yoh-Chang;Lee, Si-Kyung
    • Applied Biological Chemistry
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    • v.46 no.4
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    • pp.311-316
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    • 2003
  • This study was carried out to investigate the effect of pastry margarine content and number of layers on moisture content, baking loss, specific loaf volume and the vapor action in the manufacturing process of puff pastry. As the number of layers of the puff pastry increased the moisture content of the products slightly increased. And the moisture contents of the products decreased, as the pastry margarine contents of the puff pastry increased in the same number of layers. The baking loss of the products tended to decrease as the number of layers increased. On the other hand, as the pastry margarine contents of the puff pastry increased, the baking loss of the product increased. When the pastry margarine content in puff pastries became 130%, 81 layers provided the maximum specific loaf volumes $21.62{\pm}0.79\;ml/g$ of puff pastries. When 110% of margarine and 256 layers were applied for preparation of puff pastry, the number of vapor action was $8.25{\pm}0.50$ with the vapor action size of 9-15 mm.

Behavior of sand columns reinforced by vertical geotextile encasement and horizontal geotextile layers

  • Shamsi, Mohammad;Ghanbari, Ali;Nazariafshar, Javad
    • Geomechanics and Engineering
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    • v.19 no.4
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    • pp.329-342
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    • 2019
  • In this paper, the effect of a group of sand columns in the loose soil bed using triaxial tests was studied. To investigate the effect of geotextile reinforcement type on the bearing capacity of these sand columns, Vertical encased sand columns (VESCs) and horizontally reinforced sand columns (HRSCs) were used. Number of sixteen independent triaxial tests and finite element simulation were performed on specimens with a diameter of 100 mm and a height of 200 mm. Specimens were reinforced by either a single sand column or three sand columns with the same area replacement ratio (16%) to evaluate the Influence of the column arrangement. Effect the number of sand columns, the length of vertical encasement and the number of horizontal reinforcing layers were investigated, in terms of bearing capacity improvement and economy. The results indicated that the ultimate bearing capacity of the samples with three ordinary sand columns (OSCs) is eventually about 11% more than samples with an OSC. Also, comparison of the column reinforcing modes showed that four horizontal layers of geotextile achieved similar performance to a vertical encasement geotextile at the 50% of the column height, from the viewpoint of strength improvement, while from the viewpoint of economy, the geotextile needed for encasing the single column is around 2.5 times of the geotextile required for four layers.

Function Approximation Based on a Network with Kernel Functions of Bounds and Locality : an Approach of Non-Parametric Estimation

  • Kil, Rhee-M.
    • ETRI Journal
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    • v.15 no.2
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    • pp.35-51
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    • 1993
  • This paper presents function approximation based on nonparametric estimation. As an estimation model of function approximation, a three layered network composed of input, hidden and output layers is considered. The input and output layers have linear activation units while the hidden layer has nonlinear activation units or kernel functions which have the characteristics of bounds and locality. Using this type of network, a many-to-one function is synthesized over the domain of the input space by a number of kernel functions. In this network, we have to estimate the necessary number of kernel functions as well as the parameters associated with kernel functions. For this purpose, a new method of parameter estimation in which linear learning rule is applied between hidden and output layers while nonlinear (piecewise-linear) learning rule is applied between input and hidden layers, is considered. The linear learning rule updates the output weights between hidden and output layers based on the Linear Minimization of Mean Square Error (LMMSE) sense in the space of kernel functions while the nonlinear learning rule updates the parameters of kernel functions based on the gradient of the actual output of network with respect to the parameters (especially, the shape) of kernel functions. This approach of parameter adaptation provides near optimal values of the parameters associated with kernel functions in the sense of minimizing mean square error. As a result, the suggested nonparametric estimation provides an efficient way of function approximation from the view point of the number of kernel functions as well as learning speed.

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A Method for Reducing the Number of Metal Layers for Embedded LSI Package

  • Ohshima, Daisuke;Mori, Kentaro;Nakashima, Yoshiki;Kikuchi, Katsumi;Yamamichi, Shintaro
    • Journal of the Microelectronics and Packaging Society
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    • v.17 no.4
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    • pp.27-33
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    • 2010
  • We have successfully demonstrated a high-pin-count and thin embedded-LSI package to realize next generation's mobile terminals. The following three design key points were applied: (i) Using Cu posts, (ii) Using the coreless structure, (iii) Using a Cu plate as the ground plane. In order to quantitatively determine the contribution of the three points, the five-stage process for reducing the number of metal layers is described by means of the electrical simulation. The point-(i) and (ii) are effective from the viewpoint of the power integrity (PI); that is, these points play important roles in reducing the number of metal layers, and especially the point-(ii) contributes at least twice as the point-(i). The point-(iii) is not effective in the PI, but has a few effects on the signal integrity (SI). For reducing the number of metal layers, we should, at first, pay attention whether the PI characteristics fulfill the specification, and then we should confirm the SI characteristics.

Atomic Structure Analysis of BaO Layers on the Si(100) Surface by Impact-Collision ion Scattering Spectroscopy

  • Hwang, Yeon
    • Korean Journal of Crystallography
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    • v.17 no.2
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    • pp.51-54
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    • 2006
  • BaO layers were formed on the Si(100) surface by thermal evaporation of barium metal with simultaneous oxidation. The atomic structure of BaO layers at the initial stage of the deposition was investigated by the scattering intensity variation of $He^+$ions on time-of-flight (TOF) impact-collision ion scattering (ICISS). The results show that several number of BaO layers are formed on the Si(100) surface with the lattice parameter of bulk phase, and the occupation of oxygen atoms of the BaO layers is on-top site of silicon atoms.