Bibliographies thématiques / L-beams

Littérature scientifique sur le sujet « L-beams »

Auteur : Grafiati
Publié le 18 mai 2024

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Articles de revues sur le sujet "L-beams"

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Ma, Xiaolu, Dajun Liu, Yaochuan Wang, Hongming Yin, Haiyang Zhong et Guiqiu Wang. « Propagation of Rectangular Multi-Gaussian Schell-Model Array Beams through Free Space and Non-Kolmogorov Turbulence ». Applied Sciences 10, no 2 (8 janvier 2020) : 450. http://dx.doi.org/10.3390/app10020450.

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In this paper, rectangular multi-Gaussian Schell-model (MGSM) array beams, which consists N×D beams in rectangular symmetry, are first introduced. The analytical expressions of MGSM array beams propagating through free space and non-Kolmogorov turbulence are derived. The propagation properties, such as normalized average intensity and effective beam sizes of MGSM array beams are investigated and analyzed. It is found that the propagation properties of MGSM array beams depend on the parameters of the MGSM source and turbulence. It can also be seen that the beam size of Gaussian beams translated by MGSM array beams will become larger as the total number of terms, M, increases or coherence length, σ , decreases, and the beam in stronger non-Kolmogorov turbulence (larger α and l 0 , or smaller L 0 ) will also have a larger beam size.
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Brosnan, David P., et Chia-Ming Uang. « Effective Width of Composite L-Beams in Buildings ». Engineering Journal 32, no 2 (30 juin 1995) : 73–80. http://dx.doi.org/10.62913/engj.v32i2.640.

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The latest AISC design specifications permit the use of wider effective widths for steel-concrete composite exterior beams (or L-beams) than previous editions. This sometimes results in more flexible beams which quite often support deflection-sensitive nonstructural components. An analytical study of composite L-beams was conducted within a practical range of span and spacing for buildings. Both the conventional stress-based and rational stiffness-based definitions of effective width were considered. Effective widths were computed from the results of finite element analysis of three dimensional models permitting longitudinal slip between the concrete slab and the steel beam. It was concluded that the AISC effective width criteria for L-beams tends in an unconservative direction; a stiffness-based formula dependent on the spacing/span ratio is proposed.
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Wang, Qiang, et Chun Ling Lu. « Durability Experimental Study on RC Beams Strengthened with CFRP ». Key Engineering Materials 400-402 (octobre 2008) : 519–24. http://dx.doi.org/10.4028/www.scientific.net/kem.400-402.519.

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The principle of electrochemistry is adopted in this test. The current is switched on 7 RC beams strengthened with CFRP of different measures (include: not strengthened L-0, strengthened with one layer of CFRP on the bottom L-1, coated only with epoxy resin L-2, strengthened with one layer of CFRP on the bottom and coated with epoxy resin on the lateral L-3, strengthened with two layers of CFRP on the bottom L-4, strengthened with one layer of CFRP on the bottom and alternately on the lateral L-5, strengthened with CFRP entirely L-6) when the beams are working in corrosive environment. So the corrosion speed of the beams becomes fast. Comprehensive comparison of mechanical property and transformation rule among them has been made. The different effects of the enhancement in durability are analyzed and its reason is researched. The test results indicate that the durability of the beams strengthened with CFRP can be enhanced significantly especially in the beam strengthened with CFRP entirely L-6.
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Xiong, Liang Cai, Quan Sheng Zhou et Peng Chen. « Vibration Analysis of Different Micro-Beams with Laser Ablation ». Applied Mechanics and Materials 462-463 (novembre 2013) : 428–31. http://dx.doi.org/10.4028/www.scientific.net/amm.462-463.428.

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The dynamic response of different micro-beams after laser excitation experiments have been investigated in this paper. The impact force that induces the vibration of micro-beams is the interaction of focused pulse laser and tested beams. The impact response of micro-beams after being excited is measured by Laser Doppler Vibrometer. Different beams such as cantilever beam, L-shaped beam are employed in our experiments. Comparisons of the vibration velocity and its frequencies of different beams have also been performed. Experimental results show that the mechanical effects of laser shock do really exist and can be utilized.
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Jasim Mohammed, Thaer, Badorul Hisham Abu Bakar et Norazura Muhamad Bunnori. « Effects of Thickness of Ultra High-Performance Fiber Concrete Wrapping on the Torsional Strength of Reinforced Concrete Beam ». Applied Mechanics and Materials 802 (octobre 2015) : 161–65. http://dx.doi.org/10.4028/www.scientific.net/amm.802.161.

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Abstract: Two groups of rectangular beams, comprising of six specimens, the first group (L) were provided with four longitudinal bars, one at each corner while the second groups of beams (S) were fully reinforced with longitudinal bars and transverse reinforcement. Each group consisted of three beams. Two beams have been strengthened with ultra high performance fiber concrete (UHPFC) on four sides having a thickness of (15mm - 25mm) and one control beam. The variables considered in the experimental study include the transverse reinforcement ratios and the effect of thickness of UHPFC wrap. Experimental results show the effectiveness of the proposed technique at ultimate torque for strengthening beams and behavioral curves. Strengthened RC beams fully wrapped with a thin layer of UHPFC exhibit an enhanced torsional strength when compared to control beam. Results reveal that the transverse reinforcement ratios by 0.66%, increases the UHPFC contribution to torsional strength of strengthened beams with a 15 thick UHPFC; and by up to 7% for strengthened beams with a 25 thick UHPFC, respectively when compared to same strengthened beams without stirrup. It is found that the ultimate torque of beams with a 25 mm thin layer UHPFC is greater than beams with 15 mm by (28% and 28.3%) for the groups L and S, respectively.
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Knyazev, Boris, Natalya Osintseva, Maxim Komlenok, Vladimir Pavelyev, Vasily Gerasimov, Oleg Kameshkov, Yulia Choporova et Konstantin Tukmakov. « Terahertz Bessel Beams Formed by Binary and Holographic Axicons ». Photonics 10, no 6 (20 juin 2023) : 700. http://dx.doi.org/10.3390/photonics10060700.

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The characteristics of high-power vortex Bessel beams in the terahertz range (λ=141 μm) obtained with the use of diffractive axicons (DAs) illuminated by a Gaussian beam of the Novosibirsk free-electron laser were studied. Two of the three possible types of DA recently described in our previous paper, namely, binary spiral silicon axicons (BAs), forming beams with a topological charge l equal to 0–4 and 9, and a diamond “holographic” axicon (HA), forming a beam with l=9, were used in the experiments. These axicons formed beams whose cross sections in the region of inner Bessel rings were close to those of ideal Bessel beams, but their intensities varied in azimuth with a frequency of l and 2l for the BAs and HA, respectively. However, in the case of the BAs, the beams had a pronounced helical structure at the periphery, whereas for the HA, the beam was axisymmetric. By focusing these beams with a lens, we studied the structure of the so-called “perfect” beams (PBs). While an ideal Bessel beam exhibits a PB as a thin ring, in the case of the BAs, we observed a broadened ring structure consisting of 2l short spirals, and for the HA, we observed a narrow ring with 2l maxima in azimuth. A comparison of the numerical calculations and experiments showed that the observed azimuthal intensity variations can be attributed to inaccuracies in the preparation of the axicon relief and/or discrepancies between the calculated and actual wavelengths, within a few percent. The results of this work enable the establishment of quality requirements for axicon manufacture and the appropriate selection of the axicon type in accordance with the requirements for the beam.
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Fašalek, Andrej, Aleš Straže, Bogdan Šega, Johannes A. J. Huber et Milan Šernek. « Bonding Performance of Melamine–Urea–Formaldehyde and Polyurethane Adhesives for Laminated Hybrid Beams and Their Selected Mechanical Properties ». Buildings 13, no 8 (17 août 2023) : 2087. http://dx.doi.org/10.3390/buildings13082087.

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Beech (Fagus Sylvatica L.) is a prevalent tree species in Slovenia and is suitable for manufacturing glulam beams. However, beech wood has certain limitations that can potentially be mitigated by combining it with Norway spruce (Picea abies (L.) Karst.) wood to create hybrid beams. This study aimed to determine the bonding performance of commonly used melamine–urea–formaldehyde and polyurethane adhesives for these hybrid beams. Moreover, how varying the proportion of beech wood in a hybrid beam affects its mechanical properties was examined. Shear and delamination tests (method B) were conducted, and EN 14080:2013 requirements were met in all cases. The four-point bending tests of the beams showed that hybrid beams containing 20% of beech wood in the cross-sectional height on each side of the neutral axis exhibited a similar modulus of elasticity values as pure beech beams, but their strength was not equally improved. Hybrid beams with 11% of beech wood did not show any improvement in bending stiffness or strength compared to pure spruce beams. It was noted that the presence of beech wood in a hybrid beam can influence its failure mode. Furthermore, analytical calculations showed that a symmetrical lay-up is preferable to an asymmetrical one to increase the effective modulus of elasticity.
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Nairat, Mazen. « Axial Angular Momentum of Bessel Light ». Photonics Letters of Poland 10, no 1 (31 mars 2018) : 23. http://dx.doi.org/10.4302/plp.v10i1.787.

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Both linear and angular momentum densities of Bessel, Gaussian-Bessel, and Hankel-Bessel lasers are determined. Angular momentum of the three Bessel beams is illustrated at linear and circular polarization. Axial Angular momentum is resolved in particular interpretation: the harmonic order of the physical light momentum. Full Text: PDF ReferencesG. Molina-Terriza, J. Torres, and L. Torner, "Twisted photons", Nature Physics 3, 305 - 310 (2007). CrossRef J Arlt, V Garces-Chavez, W Sibbett, and K Dholakia "Optical micromanipulation using a Bessel light beam", Opt. Commun., 197, 4-6, (2001). CrossRef L. Ambrosio and H. Hernández-Figueroa, "Gradient forces on double-negative particles in optical tweezers using Bessel beams in the ray optics regime", Opt Exp, 18, 23 (2010). CrossRef I. Litvin, A. Dudley and A. Forbes, "Poynting vector and orbital angular momentum density of superpositions of Bessel beams", Opt Exp, 19, 18 (2011). CrossRef K Volke-Sepulveda, V Garcés-Chávez, S Chávez-Cerda, J Arlt and K Dholakia "Orbital angular momentum of a high-order Bessel light beam" , JOP B 4 (2). 2002. CrossRef M. Verma, S. Pal, S. Joshi, P. Senthilkumaran, J. Joseph, and H Kandpal, "Singularities in cylindrical vector beams", Jou. of Mod. Opt., 62 (13), 2015. CrossRef R. Borghi, M. Santarsiero, and M. Porras, "Nonparaxial Bessel?Gauss beams", J. Opt. Soc. Am. A, 18 (7) (2011). CrossRef L. Allen, M. Beijersbergen, R. Spreeuw, and J. Woerdman, "Orbital angular momentum of light and the transformation of Laguerre-Gaussian Laser modes", Phys Rev A, 45 (11): 8185-8189 (1992). CrossRef D. Mcglion and K. Dholakia, "Bessel beams: diffraction in a new light", Cont. Phys, 46(1) 15 ? 28. (2005). CrossRef F. Gori, G. Guattari and C. Padovani," Bessel-Gauss Beams", Opt. Commun., 64, 491, (1987). CrossRef V. Kotlyar, A. Kovalev, and A. Soifer, "Hankel?Bessel laser beams" J. Opt. Soc. Am. A, 29 (5) (2012). CrossRef L. Allen and M. Babiker "Spin-orbit coupling in free-space Laguerre-Gaussian light beams", Phys. Rev. A 53, R2937. CrossRef
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Sudarsana, I. Ketut, I. Putu Chandra Sajana et I. Gusti Ngurah Oka Suputra. « Applications of bolted steel plates to shear strengthening of RC beams ». MATEC Web of Conferences 276 (2019) : 01002. http://dx.doi.org/10.1051/matecconf/201927601002.

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Many reinforced concrete beams have been found deficiencies in shear due to lack of shear reinforcement. Few researches have been done to investigate shear strengthening of low concrete strength of RC beams using bolted steel plates. This paper presents experimental results on the behaviour of RC beams strengthening using full steel plates along the shear span fixed with bolts. Nine RC beams having dimension of 150x200x1500mm were tested to failure on simply supports with four point loadings setup. The beams were reinforced with tension rebars area of 289.8 mm2 (2D10+1D13) and transvers reinforcement of Ø6-125. Two dial gauges were installed at the beam middle span to measure beam deflection during the test. The results show that the applications of steel plate and bolts as external reinforcement increase beam shear capacity, stiffness and delay the occurrence of first diagonal cracks. Beams stregnthened with U-shape plates gave better performances than the beams with two pieces of L-shape plates due to better achorages.
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Dai, Xianzhi, Zhang Zhang, Wang Chen, Lijun Wang, Yong Wang et Min Zheng. « A 3D multi-directional and multimodal broadband vibration energy harvester using an L-shaped bending beam ». Journal of Physics : Conference Series 2527, no 1 (1 juin 2023) : 012076. http://dx.doi.org/10.1088/1742-6596/2527/1/012076.

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Abstract A three-dimensional (3D), multi-directional and multimodal broadband vibration energy harvester using L-shaped curved beams is proposed in this paper. The harvester is composed of an L-shaped cylindrical bending beam and a piezoelectric beam. The free ends of the L-shaped bending beam and the piezoelectric beam are respectively fixed with a magnet. These two beams are coupled by nonlinear magnetic force introduced by the two magnets. The results show that the prototype can collect 3D multi-directional broadband vibration energies and has three natural frequencies in 3D directions. Under 5 m/s2 acceleration, the prototype obtains 42.1V, 45.0V and 66.9V peak-peak voltages in the x-direction, y-direction and z-direction respectively, and the widest 3 DB bandwidths in this three directions reach up to 6.4Hz, 6.3Hz and 4.2Hz, respectively.
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Thèses sur le sujet "L-beams"

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Shetty, Suhas Gururaj. « Failure Modeling of Curved Composite Beams : Numerical Modeling of Failure Onset and Propagation in L-Profile Beams ». Thesis, KTH, Lättkonstruktioner, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-244415.

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The high strength/stiffness-to-weight ratio that composite materials exhibit has led to the utilization of composites as alternative to traditional materials in weight-critical applications. However, the highly anisotropic nature of composites renders the strength prediction under complex loading challenging. To efficiently predict the failure of composite structures especially in cases where out-of-plane stresses are dominant, the modeling of damage onset and propagation plays an essential role in accurate strength predictions.Firstly, in this Thesis work the analysis of a composite L-profile, which is loaded such that significant out-of-plane stresses are generated in the curved region, is conducted. However, the inherent heterogeneity at the micro/meso scale is not modeled for the stress analysis.Secondly, in this project the target was to accurately predict the initiation of failure at the ply level, modal based Puck’s matrix failure criteria have been implemented to the failure analysis. Maximum stress failure criteria were however retained to check the possible fiber-based failure which is not directly captured with in Puck’s failure criterion.Thirdly, Cohesive Zone Material Model has also been employed to model the growth of interlaminar damage (delamination). The delamination study is based on the Inter Fibre Fracture crack initiation and doesn’t include other causes like edge effects, voids, manufacturing defects etc.Finally, the attempt to validate the analysis results with the available test results was made. Further development of the existing model and several tests are required to be carried out for material characterization and complete validation of the developed damage model for composite structure.
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Pastore, Marcus Vinícius Filiagi. « Contribuição ao projeto de vigas delgadas de seção \"L\" de concreto pré-moldado ». Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-03092015-085641/.

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Esta dissertação tem por objetivo contribuir para o projeto estrutural de vigas delgadas de seção \"L\" de concreto pré-moldado, também conhecidas no Brasil como vigas suporte-peitoril. O projeto deste tipo de viga apresenta uma maior complexidade que o de vigas usuais pela seção transversal assimétrica, carregamento excêntrico e as várias possibilidades de ligações viga-pilar e viga-laje. Em função de sua ligação com a laje, o comportamento deste tipo de viga pode apresentar diferentes modelos: a) com torção de equilíbrio; b) sem torção de equilíbrio; e c) com restrição parcial da rotação da laje. É mostrado que para relações altura da viga/largura da mesa inferior maiores que 2,5, a variação da orientação dos eixos principais de inércia com relação aos eixos vertical e horizontal pode ser desprezada. Além disso, o centro de cisalhamento pode ser considerado situado na linha de centro da alma para grandes relações altura da viga/altura da aba. Também são discutidas as ações e efeitos a serem considerados no projeto de vigas de seção \"L\". Em relação ao estado limite último, é mostrado que os procedimentos de dimensionamento de momento fletor e força cortante não diferem dos outros tipos de vigas de concreto, entretanto, o momento de torção pode ser tratado como flexão de placa por um método recomendado na última revisão do ACI-318. O comportamento da ligação alma/aba é considerado como dente de concreto e os seguintes aspectos de seu dimensionamento são apresentados: cálculo do tirante, cálculo da suspensão, cálculo da armadura longitudinal e verificação da biela crítica. Além disso, é levada em conta a resistência à punção da aba para efeito de forças concentradas. Também são discutidas as considerações para a flexão do peitoril que pode ocorrer pela ação lateral do vento e do impacto de veículos. Em relação ao estado limite de serviço, são apresentadas duas situações exclusivas para vigas de seção \"L\" com peitoril alto e delgado: formação de fissuras na extremidade e deformação lateral excessiva. Por fim, um exemplo de aplicação é desenvolvido para ilustrar particularidades no dimensionamento de vigas delgadas de seção \"L\" de concreto pré-moldado.
This thesis aims to contribute to the structural design of precast concrete slender L-shaped beams, also known as facade beams, spandrel beams, L-shaped edge beams and others. The design of these beams shows a greater complexity than usual concrete beams due to the asymmetric cross section, eccentric loads and the various possibilities for beam-column and beam-slab connections. According to their connection with the slab, the beam behavior can be divided into different models: a) with equilibrium torsion; b) without equilibrium torsion; c) with partial restriction of the slab rotation. It is shown that for height-to-total width ratios larger than 2.5, the variation of the orientation of the principal axes with respect to the vertical and horizontal axes can be neglected. Furthermore, the shear center can be considered located at the web center line for high values of the beam height-to-ledge height ratio. It is also discussed the actions and effects to be considered in the design of L-shaped beams. Regarding the ultimate limit state, it is shown that the bending moment and shear force procedures do not differ from other types of concrete beams, however, the torsion can be treated as plate bending by a recent method recommended in the latest ACI-318 revision. The ledge is considered as dapped end beams and the following aspects of its design are presented: transverse bending; hanger requirements; longitudinal bending and shear strength, including punching shear. It is also discussed the considerations for web flexure that may occur by wind action and lateral vehicle impact. Regarding the serviceability limit state, it is presented two unique situations for precast concrete slender L-shaped beams: crack formation at end regions and excessive lateral deflection. Lastly, an example is developed to illustrate particularities of the precast concrete slender L-shaped beam design.
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Scott, Jonathan Paul. « First direct measurement of F←L using ISR events in deep inelastic scattering at HERA ». Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326678.

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Ferri, Lorenzo. « Il metodo del beam-forming acustico ». Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8735/.

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Nel corso di questa tesi si svilupperà il metodo del Beam-forming acustico, uno dei più semplici algoritmi di elaborazione segnale che permette di isolare spazialmente un suono proveniente da una precisa direzione decisa da noi, creando quindi un microfono super-direzionale orientabile a partire da un array microfonico di caratteristiche note. Inoltre si implementerà in modo pratico l'algoritmo per descrivere il livello sonoro emesso da ogni punto di una sorgente sonora estesa in modo da mappare l'intensità di quest'ultima in un'immagine 2D da sovrapporre all'immagine stessa dell'oggetto. Volendo schematizzare in breve questa tesi, essa è composta da una prima parte teorica contenente gli argomenti che ci servono per descrivere lo spazio acustico e le onde acustiche, una seconda parte riguardante i microfoni e i suoi vari parametri, una terza parte riguardante la teoria sull'elaborazione segnale nel dominio del tempo e delle frequenze e in particolare cenni sulla trasformata di Fourier. Nella parte successiva verranno descritti i due principali metodi di Beam-forming acustico trattando sia gli apparati di misura sia i due algoritmi, facendo sempre riferimento alle parti di teoria necessarie alla spiegazione del metodo. Infine nell'ultima parte della tesi verrà discusso in primo luogo la creazione del microfono virtuale, in particolare parleremo della sua sensibilità in funzione della direzione avvalendoci di uno schema che in letteratura viene denominato Beam-pattern, in secondo luogo parleremo di come creare la mappa 2D dove effettivamente possiamo vedere l'intensità sonora dell'onda proveniente da ogni punto dell'oggetto preso in considerazione.
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Hashtroodi, Seyedowjan. « Crack Propagation Analysis of a Pre-stressed L-shaped Spandrel Parking Garage Beam ». University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1420753991.

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Moreno, Tinjaca Maria Alexandra. « Effect of electron beam irradiation on quality and shelf-life of Tommy Atkins mango (Mangifera indica l.) and blueberry (Vaccinium corymbsum l.) ». Texas A&M University, 2005. http://hdl.handle.net/1969.1/4726.

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The main goal of this research was to determine the feasibility of using electron beam irradiation as an alternative disinfestation technology while preserving the overall quality of mangoes, and to verify its suitability for the preservation shelf life of blueberries. Physicochemical and sensory characteristics of the fruits were evaluated. Mangoes were irradiated at 1.0, 1.5 and 3.1 kGy using a 10MeV (10 kW) linear accelerator (LINAC) with double beam fixture. Samples were stored at 12ºC and 62.7% RH for 21 days. Blueberries packed in plastic clamshell containers were irradiated at 1.1, 1.6 and 3.2 kGy doses using the same linear accelerator with a single beam. The shelf life of the berries stored at 5ºC and 70.4% RH was evaluated for 14 days. The firmness of mangoes irradiated at 1.5 and 3.1 kGy significantly (p > 0.05) decreased during storage. There was a reduction of total sugars (8.1% and 14.1%) in samples irradiated at 1.0 kGy and 1.5 kGy, respectively. All irradiated mangoes had significantly lower (50- 70 %) ascorbic acid content throughout storage. The phenolic compounds increased in samples irradiated at 1.5 kGy (27.4%) and 3.1 kGy) (18.3%). Sensory evaluation of the fruits irradiated with 3.1 kGy showed significantly less acceptability for overall quality, color, texture and aroma. Irradiation of blueberries at 1.1 kGy had no significant (p > 0.05) effect on the fruits' physicochemical characteristics with the exception of ascorbic acid which decreased by 17% after 14 days. A significant decrease in texture (firmness) of irradiated berries was observed during storage time. Total sugars decreased in all irradiated fruits while total phenolics and tannins increased (10 -20%). Sensory attributes of samples irradiated with 1.1 kGy and 1.6 kGy were found acceptable by the panelists. The high dose-treated fruits were considered unacceptable. The results from this research suggest that a 1.5 kGy is the best treatment to maintain the quality attributes of mangoes and increase the shelf life by three days. The electron beam irradiation of packed blueberries at doses of 1.1 and 1.6 kGy ensures and enhances the quality and the shelf life of blueberries up to 14 days.
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Capoani, Federico. « Adiabatic extraction models for beam dynamics ». Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/12056/.

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Il presente lavoro prende le mosse da un problema di dinamica dei fasci relativo a un metodo di separazione di un fascio di particelle recentemente messo in funzione nell’sincrotrone PS al CERN. In questo sistema, variando adiabaticamente i parametri di un campo magnetico, nello spazio delle fasi si creano diverse isole di stabilità (risonanze) in cui le particelle vengono catturate. Dopo una parte introduttiva in cui si ricava, a partire dalle equazioni di Maxwell, l’hamiltoniana di una particella sottoposta ai campi magnetici che si usano negli acceleratori, e una presentazione generale della teoria dell’invarianza adiabatica, si procede analizzando la dinamica di tali sistemi. Inizialmente si prende in considerazione l’hamiltoniana mediata sulle variabili veloci, considerando perturbazioni (kick) dei termini dipolare e quadrupolare. In ognuno dei due casi, si arriva a determinare la probabilità che una particella sia catturata nella risonanza. Successivamente, attraverso un approccio perturbativo, utilizzando le variabili di azione ed angolo, si calcola la forza della risonanza 4:1 per un kick quadrupolare.
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Pause, Marion. « Soil moisture retrieval using high spatial resolution Polarimetric L-Band Multi-beam Radiometer (PLMR) data at the field scale ». Diss., lmu, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-132176.

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Chang, Patrick. « An improved size, matching, and scaling synthesis method for the design of meso-scale truss structures ». Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41138.

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The recent improvement of additive manufacturing has allowed designers to achieve a level of complexity and customizability that is difficult or impossible to accomplish using traditional manufacturing processes. As a result, much research has been conducted on developing new methods to utilize the larger design space brought by additive manufacturing. One such research area is in the design of mesoscale lattice structures. Mesoscale lattice structures are a type of cellular structure with support element sizes on the order of magnitude of centimeters. These types of structures are engineered for high performance and have applications in industries where both low weight and high strength are desired. However, due to the small size of their struts, these structures can easily have hundreds to thousands of individual struts. As a result, design poses a unique challenge. Current methods approach design of mesoscale lattice structures as a topological optimization problem, treating each strut diameter in the structure as a design variable. For structures with a fewer number struts, these optimization methods can converge, but will generally be very time-consuming. For structures with a large number of struts, the optimization problem becomes too large for current algorithms to solve. In previous research, a new, highly efficient design method for mesoscale lattice structures was presented that eliminates the need for global size or topological optimization. This method, termed the Size, Matching and Scaling method, used a unique combination of a solid-body finite element analysis and a library of pre-defined lattice configurations, termed the "unit-cell library," to generate lattice topologies. The results from this method were highly promising: design time was significantly reduced when compared to optimization methods. Furthermore, lattices designed using the SMS method had performance results that were either comparable or better than their optimized counterparts. However, the method developed was highly conceptual, lacking a true systematic methodology for generating topologies and suffering from some gaps in implementation. In this research, we present a modified Size Matching and Scaling (SMS) design method. Firstly, we introduce and outline the modified methodology. This methodology particularly includes an optimization step for determining strut diameters that replaces the manual search used in the original method. Secondly, we expand and explore the unit-cell library in an attempt to improve the performance of lattices generated using the SMS method. In particular, we optimize several unit-cell configurations and compare their performance in the context of the SMS method. Finally, we test the updated SMS methodology and unit-cell library using various design examples. Results from the various example problems indicate that optimization is not only a viable systematic method for determining diameter values, but is actually preferred to the manual, iterative process used in the original method. Furthermore, various optimization algorithms and approaches yield different results. Between the two optimization algorithms utilized in this method: constrained optimization and least-squares minimization, constrained minimization converges faster, but least-squares minimization yields slightly improved performance results. In addition to these algorithms, a one-variable approach using an untested, simplifying assumption, dubbed the "28% approach," was tested. Results indicate that this assumption was incorrect and cannot be utilized. Finally, results from the expanded unit-cell library indicate that the best unit-cell configuration is still the same original unit-cell configuration utilized in the first SMS method. The addition of more unit-cell does not improve the performance of structures generated using the SMS method. In fact, both performance and design time worsen when additional configurations are utilized.
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Carlini, Gianluca. « Artefatti di ricostruzione nella tomografia computerizzata con raggi X ». Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16933/.

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Gli artefatti da ricostruzione sono problemi comuni nella tomografia computerizzata con raggi X. Essi possono degradare la qualità di una immagine al punto da renderla inutilizzabile. Scopo dell’elaborato è l’analisi di diversi tipi di artefatti, a partire dai fenomeni che li causano, fino ad arrivare ai metodi impiegati per eliminarli o quantomeno ridurli. A tal fine si è proceduto ad una approfondita ricerca bibliografica e allo studio dei testi scientifici fondamentali riguardo all’argomento. Particolare attenzione è stata rivolta al fenomeno fisico del Beam Hardening, che è tra le maggiori cause di artefatti grafici, e di cui si sono viste diverse metodologie di correzione. Sono stati poi trattati gli artefatti dovuti all’apparato di misura e gli artefatti dovuti al paziente. Per quanto riguarda le tecniche di correzione, oltre ai procedimenti di più vecchia concezione e ormai consolidati, si è dato largo spazio alle metodologie innovative, di recente applicazione e ancora oggetto di studio e ricerca, come la Dual-Energy CT e la ricostruzione iterativa. Si è visto come la ricostruzione iterativa garantisca risultati di gran lunga superiori in merito alla qualità dell’immagine ricostruita, rispetto alla canonica Filtered Back-Projection, in particolare per quanto riguarda la Low-dose CT, di grande interesse in campo medico.
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Livres sur le sujet "L-beams"

1

Thode, Jackson C. George L. Beam and the Denver & Rio Grande. Denver, Colo : Sundance Publications, 1986.

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Symposium, L. on Silicon Molecular Beam Epitaxy (1995 Strasbourg France). Silicon molecular beam epitaxy, 1995 : Proceedings of Symposium L on Silicon Molecular Beam Epitaxy of the 1995 E-MRS Spring Conference, Strasbourg, France, May 22-26, 1995. Amsterdam : Elsevier, 1995.

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E, Kasper, Parker E. H. C et European Materials Research Society. Spring Conference, dir. Silicon molecular beam epitaxy 1995 : Proceedings of Symposium L on Silicon molecular beam epitaxy of the 1995 E-MRS Spring Conference, Strasbourg, France, May 22-26, 1995. Amsterdam : North-Holland, 1995.

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International Symposium on Silicon Molecular Beam Epitaxy (6th 1995 Strasbourg, France). Selected topics in group IV and II-VI semiconductors : Proceedings of Symposium L, 6th International Symposium on Silicon Molecular Beam Epitaxy, and Symposium D on Purification, Doping and Defects in II-VI Materials of the 1995 E-MRS Spring Conference, Strasbourg, France, May 22-26, 1995. Amsterdam : Elsevier, 1996.

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Bessioud, Mohammed Salah. Behaviour of headed-stud shear connectors in composite L-beams. Bradford, 1988.

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(Contributor), J. Demaison, H. Hübner (Contributor) et G. Wlodarczak (Contributor), dir. Rotational, l-type, Centrifugal Distortion and Related Constants of Diamagnetic Diatomic, Linear, and Symmetric Top Molecules (Landolt-Bornstein, 2/24/a). Springer, 1998.

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(Editor), Raj N. Singh, dir. Beam Processing Technologies (V L S I Electronics). Academic Press, 1989.

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Estimating the vibration level of an l-shaped beam using power flow techniques. [Washington, DC ? : National Aeronautics and Space Administration, 1987.

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Chapitres de livres sur le sujet "L-beams"

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Ekici, Yigitcan, Ender Cigeroglu et Yigit Yazicioglu. « Effect of Structural Parameters on the Nonlinear Vibration of L-Shaped Beams ». Dans Nonlinear Structures & ; Systems, Volume 1, 23–32. Cham : Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-36999-5_4.

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He, K., et W. D. Zhu. « Detection of Damage in Space Frame Structures with L-shaped Beams and Bolted Joints Using Changes in Natural Frequencies ». Dans Sensors, Instrumentation and Special Topics, Volume 6, 263–89. New York, NY : Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-9507-0_26.

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Jegadeesan, Souframanien, et Kandali Sreenivasulu Reddy. « Radiation-induced mutations in genetic enhancement and development of new crop varieties in black gram (Vigna mungo (L.) Hepper). » Dans Mutation breeding, genetic diversity and crop adaptation to climate change, 303–11. Wallingford : CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0031.

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Abstract Black gram (Vigna mungo (L.) Hepper), popularly known as urdbean or mash or black gram, is a grain legume rich in protein (25-28%), widely cultivated in the Indian subcontinent and to a lesser extent in Thailand, Australia and other Asian and South Pacific countries. Genetic improvement in this crop is hindered due to the narrow genetic base. As genetic variability is a prerequisite for any crop improvement programme, induced mutations provide an important source for generating variability. Radiation (gamma, X-rays and neutron) induced mutants were identified for various morphological and biochemical traits, creating a pool of genetic variability. These mutants were used in a cross-breeding programme to develop high-yielding, disease-resistant varieties in black gram. The effective blend of mutation and recombination breeding at the Bhabha Atomic Research Centre has resulted in the release of five black gram varieties (TAU-1, TAU-2, TPU-4, TU94-2 and TU-40) by incorporating desirable traits like large seed, wider adaptability, resistance to disease and improved quality. These varieties have been developed from mutants directly or by using them in cross-breeding programmes. For example, a black gram variety, N0.55, was irradiated with gamma-rays and electron beams to obtain a large number of mutants. The large-seed mutants, UM-196 and UM-201, were used in cross-breeding with the elite cultivar T-9 for developing the high-yielding varieties TAU-1, TAU-2, TPU-4, TU94-2 and TU-40. TAU-1 has become the most popular variety in Maharashtra state, occupying the maximum area under black gram cultivation. Induced mutations will continue to play an increasing role in generating genetic variability for various traits as a major component of environmentally sustainable agriculture.
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Canzani, Yaiza, et Jeffrey Galkowski. « The Koch–Tataru–Zworski Approach to $$L^\infty $$ Estimates ». Dans Geodesic Beams in Eigenfunction Analysis, 45–52. Cham : Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-31586-2_5.

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Kanapala, Satish, Nelapati Ananda Rao et M. Sekhar. « Beam Steering Cuboid Antenna Array for L Band RADAR ». Dans Lecture Notes in Electrical Engineering, 485–93. Singapore : Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1906-8_50.

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Samandari, Hamed, et Ender Cigeroglu. « Nonlinear Vibrations of a Flexible L-shaped Beam Using Differential Quadrature Method ». Dans Nonlinear Dynamics, Volume 1, 145–54. Cham : Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-15221-9_12.

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Sinharay, Arindam, Pranab Roy et Hafizur Rahaman. « Hausdorff Distance Driven L-Shape Matching Based Layout Decomposition for E-Beam Lithography ». Dans Communications in Computer and Information Science, 287–95. Singapore : Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-7470-7_29.

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Utsuki, Y., et K. Ikarashi. « Elastic buckling characteristics of L-shaped beam-column connection panels for H-section members ». Dans Insights and Innovations in Structural Engineering, Mechanics and Computation, 1234–40. Taylor & Francis Group, 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742 : CRC Press, 2016. http://dx.doi.org/10.1201/9781315641645-202.

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Yusop, Mohd Rafii, Yusuff Oladosu, Abdul Rahim Harun, Asfaliza Ramli, Ghazali Hussin, Mohd Razi Ismail et Norhani Abdullah. « Application of mutation techniques and genotype × environment interaction for grain yield in ion beam induced mutant rice lines tested in multiple locations in Malaysia. » Dans Mutation breeding, genetic diversity and crop adaptation to climate change, 226–34. Wallingford : CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0023.

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Abstract Genotype evaluation for stability and high yield in rice is an important factor for sustainable rice production and food security. These evaluations are essential, especially when the breeding objective is to release rice with high yields, adaptability and stability for commercial cultivation. To achieve this objective, this study was carried out to select high-yielding rice genotypes induced by ion beam irradiation. Seeds of the rice variety 'MR219' were subjected to different doses of 320 MeV carbon-ion beam irradiation to determine the optimum dose to produce high mutant frequency and spectrum. The optimum dose was 60 Gy. After several cycles of selection and fixation between 2009 and 2014 (M0-M6), six prospective lines with desirable characters were selected at the M6 generation. The selected mutant lines along with other mutant varieties were then tested at five locations in two planting seasons to select high-yielding and stable genotypes. The experiment was conducted in a randomized complete block design with three replications across the locations and seasons. The pooled analysis of variance revealed highly significant differences (p ≤ 0.01, 0.05) among genotypes, among locations and among genotypes by location by season (G×L×S interaction) for the yield traits except for seasons and genotype by season (G×S interaction). Based on univariate and multivariate stability parameters, rice genotypes were classified into three main categories. The first group comprised genotypes with high yield stability along with high yield per hectare. These genotypes include ML4 and ML6 and are widely adapted to diverse environmental conditions. One line exhibited high yield per hectare but low stability; this genotype (ML9) is suitable for specific environments. The last group had low yield per hectare and high stability and included 'MR220', 'Binadhan4' and 'Binadhan7'. This final group is more suitable for breeding specific traits or perhaps has yield component compensation. Hence, rice mutant lines ML4 and ML6 were recommended for commercial cultivation in Malaysia.
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Karthikeyan, Premkumar, Nagabushanam Hari Kumar et Srinivasan Aishwarya. « 5G-Optimizing Network Coverage in Radio Self Organizing Networks by M/L Based Beam Tilt Algorithm ». Dans Smart City 360°, 44–54. Cham : Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-33681-7_4.

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Actes de conférences sur le sujet "L-beams"

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Richter, C. C., et G. R. Heppler. « L-Spline Finite Elements ». Dans ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81747.

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The L-spline finite element method is applied to the static deflection analysis and linear vibration analysis of curved Euler-Bernoulli and Timoshenko beams. A formal definition of membrane locking is presented along with a simple test that allows a priori determination of an L-spline finite element models susceptibility to locking. Formulations for both types of beam models, that under certain discretizations experience locking are presented. Examples that demonstrate the efficacy of the locking test and illustrate the L-spline finite element method performance are included.
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Whitehouse, David R. « Divergence and Strehl ratios of L-G multimode beams ». Dans Applications in Optical Science and Engineering, sous la direction de James M. Darchuk. SPIE, 1993. http://dx.doi.org/10.1117/12.143842.

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Karadag, Vedat. « Vibration Control and Identification Analysis of Generally Cracked and Spring Added “L” Shaped Beams ». Dans ASME 8th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2006. http://dx.doi.org/10.1115/esda2006-95511.

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In this study, the analytical and experimental free vibration analysis of rectangular cross-section uniform cracked thin L shaped beam on noise isolating elastic spring, has been made by the finite element method. In the present analysis; vibration characteristics of “L” shaped beams with cracks and springs attachments have been analyzed giving particular attention to vibration control and noise identification aspects. This analysis is made by using the finite element method considering three dimensional motion of cracked L shaped beams, namely, for inplane, and out of plane bending, coupled bending-longitudinal and bending-torsional frequencies as new research aspects in the literature which, the related works are usually in plane uncoupled beam analysis. The L shaped beams were analyzed on clamped-free and free-free supported conditions. The cracks were put only one side of the beam and several types of cracks were modeled by massless rotational and longitudinal springs. The analytical and experimental results were compared with each other and with the results available in the literature, satisfactorily. As a result of analysis, it has been found that; there is a certain decrease on the natural frequencies of the beam that has different cracks, and it is concluded that, it is possible to have an exact detection and control idea about the shape and the largeness of the crack with analyzing the natural frequencies and noise patterns of the parts. The crack model used in this study is mentioned as a linear spring model used in the literature. The analytical and experimental results and comparisons show the efficiency and effectiveness of the proposed method.
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Hassan, B. N., Y. M. Hameed, K. S. Abdul-Razzaq, A. A. Dawood et W. H. Khaleel. « Elliptical L-section R.C. beams - A parametric study using ETABS ». Dans CONFERENCE ON MATHEMATICAL SCIENCES AND APPLICATIONS IN ENGINEERING : CMSAE-2021. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0148868.

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Lin, Tao, et David L. Russell. « Estimating the Interaction Kernel in a Mathematical Model for a Beam With Internal Damping Mechanism ». Dans ASME 1995 Design Engineering Technical Conferences collocated with the ASME 1995 15th International Computers in Engineering Conference and the ASME 1995 9th Annual Engineering Database Symposium. American Society of Mechanical Engineers, 1995. http://dx.doi.org/10.1115/detc1995-0675.

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Abstract Beams formed by long fiber composite materials have certain internal damping torque. A mathematical model for the displacement of this type of beams in cantilever configuration is the following initial-boundary value problem of an integro-differential equation [1, 14]: (1) ρ ( x ) w t t ( x , t ) − 2 ( ∫ 0 L h ( x , y ) [ w t x ( x , t ) − w t x ( y , t ) ] d y ) x + ( E I w x x ( x , t ) ) x x = f ( x , t ) , (2) w ( 0 , t ) = 0 , w x ( 0 , t ) = 0 , (3) w x x ( L , t ) = b l 1 ( t ) , (4) − ( E I w x x ( x , t ) ) x | x = L + 2 ∫ 0 L h ( L , y ) [ w t x ( L , t ) − w t x ( y , t ) ] d y = b l 2 ( t ) , (5) w ( x , 0 ) = w 0 ( x ) , w t ( x , 0 ) = w 1 ( x ) , where L is length of the beam, w(x, t) is the transverse displacement of the beam at time t and position x, ρ(x) is the mass density, EI is the stiffness parameter. The interaction integral kernel h(x, ξ) is introduced in this model by considering a restoring torque which comes from spatially variable bending of the beam. This kernel h(x, ξ) depends on the material properties of the beam. Choosing a different material (different h(x, ξ)) can realize a different damping effect for the beam.
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Churnside, James H. « Geometric optics approach to beam wander in the turbulent atmosphere ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1989. http://dx.doi.org/10.1364/oam.1989.wo3.

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The variance of the wander of an optical beam in the turbulent atmosphere is calculated using a geometric optics calculation. A uniform beam of diameter D and focal range F is assumed to propagate a distance L through the atmosphere. A geometric optics calculation and several reasonable physical assumptions lead to a simple integral expression for the one-axis wander variance. If turbulence strength C n 2 is constant along the path and the beam does not come to a focus between the transmitter and receiver, the integral can be evaluated to 0.97 C n 2 D − 1 / 3 L 3 2 F 1 ( 1 / 3 , 1 ; 4 ; L / F ) , where 2 f 1 is the hypergeometric function. This expression reduces to the expected results for collimated beams (L/F infinite) and focused beams (L/F unity). The geometric optics expression is shown to be valid for D larger than the Fresnal zone and also larger than the ratio of the square of the Fresnel zone to the lateral coherence length.
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Cao, Dong-Xing, Wei Zhang et Ming-Hui Yao. « Theoretical and Experimental Investigation of an L-Shape Beam Structure ». Dans ASME 2008 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. ASMEDC, 2008. http://dx.doi.org/10.1115/smasis2008-546.

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Flexible multi-beam structures are significant components of large space station, architecture engineering and other structural systems. The understanding of the dynamic characteristics of these structures is essential for their design and control of vibrations. In this paper, the planar nonlinear vibrations and chaotic dynamics of an L-shape flexible beam structure will be investigated using theoretical and experimental methods. The L-shape beam structure considered here is composed of two flexible beams with right-angle. The governing equations of motion for the L-shape beam structure are established firstly. Then, the method of multiple scales is utilized to obtain a four-dimensional averaged equation. Numerical method is used to analyze the nonlinear dynamic responses and chaotic motions. Finally, The experimental apparatus and schemes for measuring the amplitude of nonlinear vibrations for the L-shape beam structure are introduced briefly. Then, the detailed analysis for experimental data and signals which represent the nonlinear responses of the beam structure are given.
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He, K., et W. D. Zhu. « Finite Element Modeling of Structures With L-Shaped Beams and Bolted Joints : Model Updating and Predictive Modeling Approaches ». Dans ASME 2009 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/detc2009-87811.

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Due to bending-torsion coupled vibrations of the L-shaped beams and numerous uncertainties associated with the bolted joints, modeling structures with L-shaped beams and bolted joints is a challenging task. With the recent development of the modeling techniques for L-shaped beams by the authors [1], this work focuses on developing new finite element (FE) models for bolted joints in these structures. While the complicated behavior of a single bolted connection can be analyzed using commercial FE software, it is computationally expensive and inefficient to directly simulate the global dynamic response of an assembled structure with bolted joints, and it is necessary to develop relatively simple and accurate models for bolted joints. Three new approaches, two model updating approaches and a predictive modeling approach, are developed in this work to capture the stiffness and mass effects of bolted joints on the global dynamic response of assembled structures. The unknown parameters of the models in the model updating approaches are determined by comparing the calculated and measured natural frequencies. In the predictive modeling approach, the effective area of a bolted connection is determined using contact FE models and an analytical beam model; its associated stiffnesses can also be determined. The models developed for the bolted joints have relatively small sizes and can be easily embedded into a FE model of an assembled structure. For the structures studied, including a three-bay space frame structure with L-shaped beams and bolted joints, and some of its components, the errors between the calculated and measured natural frequencies are within 2% for at least the first 13 elastic modes, and the associated modal assurance criterion values are all over 94%.
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Haghighatjou, T., Don A. Larson et Truman D. Black. « Diffraction of Gaussian beams by stationary and traveling grating combinations ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1987. http://dx.doi.org/10.1364/oam.1987.thpo26.

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The diffraction of Gaussian beams by multiple-grating configurations is analyzed using a general operator representation. Analytical intensity expressions were obtained for the 0 and ± 1 orders of diffraction for two gratings separated by a distance L. These results exhibit features that were not evident from simpler plane wave analyses of comparable configurations. In particular, the fundamental dynamic amplitudes due to the relative motion of the gratings vary as the Gaussian beam parameters change.
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Cao, Dong-xing, Ming-hui Yao, Wei Zhang et Qian Wang. « Theoretical and Experimental Investigations of Nonlinear Vibrations for a Beam Structure ». Dans ASME 2009 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/detc2009-86375.

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This paper discusses theoretical and experimental investigations of the planar nonlinear vibrations and chaotic dynamics of a beam structure composed of two beams with right-angled L-shape. Differential equations of motion for the L-shape beam structure with two-degree-of-freedom are derived firstly by application of the substructure synthesis method and the Lagrangian equation. Then, the method of multiple scales is utilized to obtain a four-dimensional averaged equation of the structure. Based on the averaged equations, numerical simulations are presented to analyze the nonlinear responses and chaotic dynamics of the L-shape beam structure. The bifurcation diagram, phase portrait, amplitude spectrum and Poincare map are plotted to illustrate that the periodic solutions and chaotic motions occur in the planar nonlinear vibrations of the L-shaped beam structure under certain conditions. Finally, the experimental apparatus and schemes for measuring the amplitude of nonlinear vibrations for the L-shape beam structure are introduced briefly. Then, the detailed analysis for experimental data and signals which represent the nonlinear responses of the beam structure are given.
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Rapports d'organisations sur le sujet "L-beams"

1

Chang, Xiangyun, Vladimir Teryaev et Jay Hirshfield. HIGHLY-EFFICIENT 20-MW L-BAND MULTI-BEAM KLYSTRON. Office of Scientific and Technical Information (OSTI), décembre 2023. http://dx.doi.org/10.2172/2229240.

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Rizkalla, Sami, Mohamed Nafadi, Gregory Lucier, Paul Zia et Gary Klein. Behavior and Design of Directly-Loaded L-Shaped Beam Ledges. Precast/Prestressed Concrete Institute, 2016. http://dx.doi.org/10.15554/pci.rr.comp-004.

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Read, Michael, Patrick Ferguson, Lawrence Ives, Liqun Song, Bruce Carlsten et Michael Fazio. Final Report 200 MW L-Band Annular Beam Klystron for Accelerators. Office of Scientific and Technical Information (OSTI), février 2009. http://dx.doi.org/10.2172/1011380.

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Georgiou, Ioannis T., et Ira B. Schwartz. POD (K-L) Analysis of the Interaction Free Dynamics of a Beam/Pendulum Configuration : An Experimental Study. Fort Belvoir, VA : Defense Technical Information Center, avril 2001. http://dx.doi.org/10.21236/ada389827.

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Wang D., I. Ben-Zvi, X. Chang et J. Kewisch. The Start-to-End Simulation of Electron Beam in the RHIC E-cooling Facility (L-band option) with PARMELA. Office of Scientific and Technical Information (OSTI), mars 2003. http://dx.doi.org/10.2172/1061688.

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BEHAVIOUR OF REINFORCED JOINTS BETWEEN STEEL BEAM AND L-SHAPED WIDE LIMB COMPOSITE COLUMN. The Hong Kong Institute of Steel Construction, mars 2021. http://dx.doi.org/10.18057/ijasc.2021.17.1.8.

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EXPERIMENTAL STUDY OF HYSTERETIC BEHAVIOR OF RESILIENT PREFABRICATED STEEL FRAMES WITH AND WITHOUT INTERMEDIATE COLUMNS. The Hong Kong Institute of Steel Construction, septembre 2022. http://dx.doi.org/10.18057/ijasc.2022.18.3.9.

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The research innovatively proposed a seismic resilient structural system including a prefabricated self-centering steel frame (PSC) and an intermediate column with a friction damper (CD). The CD, installed in the mid-span beam of the PSC, was expected to provide additional stiffness and damping, The seismic performance of the newly-developed resilient structural system thus can be greatly improved. This paper stated the experimental study on the hysteretic behaviors of the newly-developed system. Comparative pseudo-dynamic tests were conducted for the validation where two systems, a PSC with CD and a PSC without CD, were tested respectively. The testing results indicated that a PSC with CD has better seismic performance for long-span structures under catastrophic earthquakes’ attack. The CD overall provided additional stiffness for requirements of earthquake fortification criteria. The friction damper, part of CD greatly improves the damping effect together with the energy-dissipation bolts. The small residual rotations of beam-column connections on the PSC subsystem provides a satisfactory self-centering mechanism. Moreover, the steel strands of the resilient structural system can maintain the elasticity even after the highest-intensity earthquake. In turn, the satisfactory seismic performance of the proposed PSC with CD structural system validated. This research developed a series of design formula for the T-plate and L-plate friction damper in the CD to guarantee the designed seismic performance of the proposed seismic resilient structural system. The theoretical hysteresis curve of the system was proposed for the future design specification.
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