Academic literature on the topic 'Layer by layer optimization'

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Journal articles on the topic "Layer by layer optimization"

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Lychev, S. A., G. V. Kostin, K. G. Koifman, and T. N. Lycheva. "Modeling and Optimization of Layer-by-Layer Structures." Journal of Physics: Conference Series 1009 (April 2018): 012014. http://dx.doi.org/10.1088/1742-6596/1009/1/012014.

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Swetanshu, ,., and Vijay Sharma. "Formulation, Optimization and Evaluation of Bilayer Tablet of Antihypertensive Drug." Journal of Drug Delivery and Therapeutics 9, no. 4 (July 15, 2019): 704–8. http://dx.doi.org/10.22270/jddt.v9i4.3098.

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Hypertension or high blood pressure occurs when the high cardiac output exerts pressure on the arterial wall as the blood flow increases. Bi-layer tablets are prepared with one layer of drug for immediate release while second layer designed to release drug later, either as second dose or in an extended release manner. Bi-layered tablet is suitable for sequential release of two drugs in combination, separate two incompatible substances, and also for sustained release tablet in which one layer is immediate release as initial dose and second layer is maintenance dose. Bilayer tablet is suitable for sequential release of two drugs in combination, separate two incompatible substances and also for sustained release tablet in which one Layer is immediate release as initial dose and second layer is maintenance dose. The preparation of tablets in the form of multi layers is used to provide systems for the administration of drugs. Keywords: Hypertension, Bi-layered tablet, Enalapril, Immediate release and Sustained release.
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Zhang, Chao, Jianjun Song, and Jie Zhang. "Optimization of Laser Recrystallization Process for GeSn Films on Si Substrates Based on Finite Difference Time Domain and Finite Element Method." Journal of Nanoelectronics and Optoelectronics 15, no. 3 (March 1, 2020): 376–83. http://dx.doi.org/10.1166/jno.2020.2705.

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GeSn alloy on Si substrate has the advantages of high carrier mobility, high radiation recombination efficiency, compatibility with the Si process, and is widely used in the field of semiconductor optoelectronics. However, due to the high lattice mismatch between the GeSn epitaxial layer and the Si substrate, how to prepare a perfect GeSn film on the Si substrate is an issue. The 808 nm continuous wave laser recrystallization technology can significantly improve the quality of the GeSn alloy epitaxial layer by melting and recrystallization, which provide another technical way for solving this problem. Optimized laser recrystallization related process parameters is necessary when laser recrystallization technology is used to prepare high quality GeSn alloy on Si substrate. For this purpose, the absorption, reflection and transmission models of GeSn alloy epitaxial layer/Si substrate system irradiated by 808 nm continuous wave laser are established using finite difference time domain software FDTD Solutions. The thickness-related process parameters of GeSn alloy epitaxial layer and SiO2 capping layer are optimized. In addition, the temperature distribution model of 808 nm continuous wave laser irradiation of GeSn alloy epitaxial layer on Si substrate system is obtained by COMSOL Multiphysics simulation. The process parameters related to laser recrystallization temperature are optimized and listed, which can be used as important technical references for the growth of low defect density GeSn layer on Si substrate assisted by the laser recrystallization technology.
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Abdalla, M., J. Yamin, and E. Al-Khawaldeh. "Multi-layer optimization algorithm." Journal of Algorithms & Computational Technology 16 (January 2022): 174830262110604. http://dx.doi.org/10.1177/17483026211060469.

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The optimization of experimental results has repeatedly posed major challenges for scientist and engineers. In this work, a systematic multi-layer optimization scheme is proposed in conjunction with particle swarm optimization algorithm to locate a global optimum that fits a cost function. The technique utilizes SP-lines to form three-dimensional patches surfaces from experimental data in multi-layer fashion and incorporates a multi-layer search using particle swarm optimization. The novel technique is illustrated and verified over two layers of experimental data to show its effectiveness.
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Zhao, Xiaohui, Zhenfu Shi, Chao Deng, Yu Liu, and Xin Li. "The Effect of Laser Offset Welding on Microstructure and Mechanical Properties of 301L to TA2 with and without Cu Intermediate Layer." Metals 10, no. 9 (August 24, 2020): 1138. http://dx.doi.org/10.3390/met10091138.

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Based on dissimilar materials of 301L/TA2, the effect of laser offset and copper intermediate layer on welded joints was investigated. First, the process optimization of laser offsets indicated that the tensile strength of welded joint without intermediate layer was reached to the highest value when the laser was applied on the TA2 side. On the other hand, the tensile strength of welded joint with intermediate layer performed well when laser was applied in the middle position. Then, microstructural characterization and mechanical properties of welded joints were observed and tested. Based on eutectic reaction and peritectic reaction: TiFe and TiFe2 compounds were produced for welded joint without intermediate layer. Cu-Fe solid solutions and Cu-Ti compounds were generated when copper was used as the intermediate layer. The maximum tensile strength of welded joint with and without copper intermediate layer were 396 and 193 MPa, respectively. Finally, fracture mechanism of 301L/TA2 welded joint was studied: Fe-Ti compounds caused brittle fracture of welded joints without intermediate layer; brittle fracture took place in rich copper and Cu-Ti compounds area of welded joints with copper intermediate layer.
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Baloni, Sunil Dutt, Somesh K. Sharma, Jagroop Singh, and Sushant Negi. "SLS Process Parameter Optimization to Improve Surface Quality and Accuracy of Polyamide Parts." International Journal of Manufacturing, Materials, and Mechanical Engineering 11, no. 4 (October 2021): 57–74. http://dx.doi.org/10.4018/ijmmme.2021100104.

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The contribution of selective laser sintering (SLS) technique in the 4.0 manufacturing industry is undisputedly significant. SLS part quality exhibits high dependence on SLS process parameters and is a major challenge. Therefore, this research aims to investigate the effect of input parameters (i.e., part orientation, bed temperature, and layer thickness) on the surface roughness and accuracy of laser-sintered polyamide specimens. Response surface methodology (RSM) and ANOVA analysis aided the testing and evaluation. Optimal working conditions for minimum shrinkage were 0.17 mm layer thickness, 177.89°C part bed temperature, and part orientation at 88.91 degrees. The surface quality deteriorated with the increment in part bed temperature and layer thickness, and it shows an inverse trend (or improves) with the part orientation in the prescribed range. The optimal surface roughness was at a layer thickness of 0.11 mm, bed temperature at 174.55°C, and part orientation at 86.5 degrees.
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Lee, Alvin, Jay Su, Baron Huang, Ram Trichur, Dongshun Bai, Xiao Liu, Wen-Wei Shen, et al. "Optimization of laser release layer, glass carrier, and organic build-up layer to enable RDL-first fan-out wafer-level packaging." International Symposium on Microelectronics 2016, no. 1 (October 1, 2016): 000190–95. http://dx.doi.org/10.4071/isom-2016-wa34.

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Abstract With increasing demand for mobile devices to be lighter and thinner and consume less power while operating at high speed and high bandwidth, many equipment suppliers and assembly participants have invested great efforts to achieve fine-line fan-out wafer-level packaging (FOWLP). However, the inherent warp of reconstituted wafers, which can contribute to poor die placement accuracy and/or delamination at the interface of the build-up layer and carrier, remains a major challenge. In this study, the interactions among laser release layer, glass carrier, and build-up layer were evaluated for optimization of redistribution layer (RDL)–first FOWLP as a foundation to move toward fine-line FOWLP. In this study, a series of experiments incorporating glass carrier, laser release layer, and build-up layers were carried out to determine the optimal setup for RDL-first FOWLP. First, glass carriers (300 mm × 300 mm × 0.7 mm) with coefficients of thermal expansion of 3 and 8 ppm/°C were treated with 150-nm laser release layers. After deposition of 0.1 μm of sacrificial material on the glass carrier, 8-μm build-up layers were coated and patterned by lithography to electroplate Cu interconnections with a density of approximately 10% of the surface area. Subsequent to die attachment, molding compound was applied on top to form a 200-μm protective overcoat. The reconstituted wafer was then separated from the glass carrier through a laser ablation process using a 308-nm laser to complete the design of experiments (DOE). An experiment to study the correlation of glass carrier, laser release layer, build-up layers, and molding compound in RDL-first FOWLP processes is discussed to address full process integration on 300-mm glass substrates. The combination of glass carrier, laser release layer, build-up layer, and molding compound will pave the way for realizing cost-effective RDL-first FOWLP on panel-size substrates.
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Kimmel, G., G. Shafirstein, and M. Bamberger. "Fast Thickness Measurement of Thin Crystalline Layers by Relative Intensities in XRPD Method." Advances in X-ray Analysis 32 (1988): 293–301. http://dx.doi.org/10.1154/s0376030800020607.

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In this work a continuous wave CO2 laser was used for melting a layer of amorphous alumina obtained by anodizing 6061 aluminum plates. Melting the surface of the anodized plates led to the formation of a new uniform corundum layer at the expense of some of the amorphous coating, resulting in a double layer coating of crysta11ine on amorphous.The characterization of the corundum layer is essential for process optimization study. Among the non-destructive methods X-ray diffraction is useful, because it provides us with selected data on the crystalline layer.
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Ju, Jiang, Yang Zhou, Maodong Kang, and Jun Wang. "Optimization of Process Parameters, Microstructure, and Properties of Laser Cladding Fe-Based Alloy on 42CrMo Steel Roller." Materials 11, no. 10 (October 22, 2018): 2061. http://dx.doi.org/10.3390/ma11102061.

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The mould foot roller is a key component of a continuous casting machine. In order to investigate the possibility of using laser cladding to repair mould foot roller, Fe-based powders and 42CrMo steel are used in this work. The laser cladding process parameters were optimized by orthogonal experiments. The chemical compositions, microstructure, properties of the cladding layer under the optimum process parameters, and substrate were systematically investigated by using optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), microhardness test, wear test, and salt spray corrosion test. The results indicate that the primary factor affecting the width and depth of the cladding layer is laser power. The scanning speed also has a significant effect on the height of the cladding layer. The optimum process parameters for repairing the mould foot roller are 2 kW laser power, 4 mm/s scanning speed, and 15 g/min feeding rate of powder. Along the depth direction of the cladding layer, the microstructure of the coating gradually transforms from plane crystal, cell grains, or dendrites to equiaxed grains. The matrix is mainly martensite with retained austenite; the eutectic phase is composed of netlike M2B, particulate M23(C,B)6, and M7(C,B)3 phase. The hardness of the cladding layer is significantly improved, about three times that of the substrate. The weight loss of the cladding layer is just half that of the substrate. Its wear resistance and corrosion resistance have been significantly improved. The work period of the laser cladding-repaired foot roller is much longer than for the surfacing welding-repaired one. In summary, laser cladding technology can increase the life of mould foot rollers.
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Lin, Jin Lan, and Jian Hong Fan. "Research on the Theory of the Laser Shock Processing Technology." Applied Mechanics and Materials 610 (August 2014): 1021–28. http://dx.doi.org/10.4028/www.scientific.net/amm.610.1021.

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In this paper the laser shock processing technology (LSPT) is investigated theoretically. A one-dimensional theoretical model is presented to express analytically the transmission coefficient of the incident laser beam through four different layers, i.e., the air layer, the constrained layer, the plasma layer, and the absorbing coating. Based on this model, the key parameters of LSPT can be further optimized to obtain the maximum transmission coefficient and the best surface-hardening effect. This one-dimensional theoretical model presented can be further used in guiding the parameter optimization for this technology.
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Dissertations / Theses on the topic "Layer by layer optimization"

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Angelou, Marianna. "Cross-layer optimization in optical networks." Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/83925.

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Network planning and operation in core optical networks require processes that lead to a cost-effective network able to effectively accommodate the given traffic demands. Crosslayer techniques that exploit information coming from the transport plane to serve either the network planning or the operation phases have been proposed to achieve optimal resource utilization and network performance. Dynamic impairment-aware networking refers to a solution that utilizes the dynamicity as well as the valuable physical-layer information of a reconfigurable WDM network to provide a smooth transition from the quasi-static networking of today to an intelligent reconfigurable and physical impairment-aware architecture. The concept of physical layer awareness allows intelligent techniques to offer optimal planning, dynamic configuration and management of the network while ensuring strong quality of transmission (QoT). A physical-layer performance estimating tool called Q-tool, has been designed and developed to deliver fast and accurate QoT assessments in dynamic single line-rate WDM networks employing 10 Gb/s OOK systems. The Q-tool was developed so as to feed with QoT evaluations the various cross-layer modules including offline RWA, monitor placement, regenerator placement, online RWA and failure handling. The significance of the physical-layer awareness and the role of Q-tool in the online routing strategy have been experimentally investigated using an impairment-enabled control-plane testbed. A cross-layer module that utilizes physical layer information to optimize the planning phase of single line-rate networks has been also developed; a monitor placement scheme was designed that takes into account partial monitoring information coming from the physical layer to decide the optimum number and locations of the optical monitoring devices. A techno-economic analysis was also conducted to explore the cost implications stemming from the resource optimization of a dynamic single line-rate network. Impairment aware and impairment-unaware algorithms along with the developed QoT tool were used to compare the planning solutions in terms of CapEx and OpEx. The challenges arising in the core networks of the next generation have also been addressed. Flexible optical networking has been introduced by the research community as a way to offer efficient utilization of the available optical resources while offering ultra-high speed rates. As opposed to the rate-specific and fixed-grid solution of a mixed line-rate (MLR) network, flexible networks are bandwidth agnostic and have the ability to adapt on- demand the delivered bit-rate. Yet, the increased level of flexibility imposes complex requirements; during network operation traffic is changing with time, leaving windows of spectrum of variable size unused. Moreover, interference from the neighbouring channels has to be taken into account and sufficient guard-bands ought to be considered. In such context the physical layer requirements for a spectrum-flexible optical superchannel were experimentally investigated by implementing a set of networking scenarios. The importance of the result is that it can act as input for cognitive algorithms that will enable a novel networking paradigm. Finally next generation core networks were evaluated from a cost, spectral and energy perspective so as to give a comprehensive view of the potential of the proposed technologies. The resource optimization achieved by flexible networks has been compared to single and mixed line-rate networks under the prism of cost and energy efficiency. It was shown that the capability of flexible networks to allocate efficiently the available spectrum, counterbalances the additional capital expenditures that are required to migrate to a multi-carrier system. In addition flexible networks achieve low energy per bit as they use just the amount of network resources needed for the given input traffic.
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Gifford, James Hart. "Optimization of the automated spray layer-by-layer technique for thin film deposition." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59883.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 82-83).
The operational parameters of the automated Spray-LbL technique for thin film deposition have been investigated in order to-identify their effects on film thickness and roughness. We use the automated Spray-LbL system developed at MIT by the Hammond lab to build 25 bilayer films of poly (ally amine hydrochloride) (PAH) and poly (acrylic acid) (PAA). Each of the 10 operational parameters of this system are explored individually to isolate each parameter's effect on film thickness and roughness. The parameter effects are analyzed for apparent trends to determine the parameters best suited for adjusting film thickness and roughness. The optimal parameters for thickness adjustment are polyelectrolyte solution concentration, polyelectrolyte spray time, spraying distance, air pressure and polyelectrolyte charge density. These parameters are independent of the type of species used to construct the film, and thus the trends should apply to any species used to construct thin films. The effect of each of the 10 operational parameters is examined in detail. While researching the parameter effects, polyelectrolyte interdiffusion in the films was observed. This interdiffusion is investigated using both the conventional dipped LbL and Spray-LbL deposition techniques. Interdiffusion is shown to be dependent on 3 factors, the charge density of the polyelectrolytes, the molecular weight of the polyelectrolytes, and the contact time between the polyelectrolyte solutions and the surface of the film. Interdiffusion is observed when the PAH is partially charged, the polyelectrolytes chains have a low molecular weight, and the contact time is sufficiently long enough to allow for interdiffusion. The significantly reduced contact time during the automated Spray-LbL process not only speeds up the film deposition time, but also significantly hinders the interdiffusion of PAH resulting in much thinner films than what is possible from dipping. Finally, the uniformity of the films produced using the automated Spray-LbL system is investigated. Films deposited on substrates greater than 1 in diameter area exhibit more than 20% variance in thickness. Adjustments were made to the setup of the system in an effort to expand this area of film thickness uniformity. However, it is determined that the design of this automated Spray-LbL system limits the film uniformity to an area of 1 in diameter.
by James Hart Gifford.
S.M.
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Warren, Christopher L. (Christopher Lane). "Submarine design optimization using boundary layer control." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/10529.

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Thesis (Nav. E.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1997, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1997.
Includes bibliographical references (leaves 64-67).
by Christopher L. Warren.
M.S.
Nav.E.
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Chu, Zheng. "Transmit optimization techniques for physical layer security." Thesis, University of Newcastle upon Tyne, 2016. http://hdl.handle.net/10443/3377.

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Over the last several decades, reliable communication has received considerable attention in the area of dynamic network con gurations and distributed processing techniques. Traditional secure communications mainly considered transmission cryptography, which has been developed in the network layer. However, the nature of wireless transmission introduces various challenges of key distribution and management in establishing secure communication links. Physical layer security has been recently recognized as a promising new design paradigm to provide security in wireless networks in addition to existing conventional cryptographic methods, where the physical layer dynamics of fading channels are exploited to establish secure wireless links. On the other hand, with the ever-increasing demand of wireless access users, multi-antenna transmission has been considered as one of e ective approaches to improve the capacity of wireless networks. Multi-antenna transmission applied in physical layer security has extracted more and more attentions by exploiting additional degrees of freedom and diversity gains. In this thesis, di erent multi-antenna transmit optimization techniques are developed for physical layer secure transmission. The secrecy rate optimization problems (i.e., power minimization and secrecy rate maximization) are formulated to guarantee the optimal power allocation. First, transmit optimization for multiple-input single-output (MISO) secrecy channels are developed to design secure transmit beamformer that minimize the transmit power to achieve a target secrecy rate. Besides, the associated robust scheme with the secrecy rate outage probability constraint are presented with statistical channel uncertainty, where the outage probability constraint requires that the achieved secrecy rate exceeds certain thresholds with a speci c probability. Second, multiantenna cooperative jammer (CJ) is presented to provide jamming services that introduces extra interference to assist a multiple-input multipleoutput (MIMO) secure transmission. Transmit optimization for this CJaided MIMO secrecy channel is designed to achieve an optimal power allocation. Moreover, secure transmission is achieved when the CJ introduces charges for its jamming service based on the amount of the interference caused to the eavesdropper, where the Stackelberg game is proposed to handle, and the Stackelberg equilibrium is analytically derived. Finally, transmit optimization for MISO secure simultaneous wireless information and power transfer (SWIPT) is investigated, where secure transmit beamformer is designed with/without the help of arti - cial noise (AN) to maximize the achieved secrecy rate such that satisfy the transmit power budget and the energy harvesting (EH) constraint. The performance of all proposed schemes are validated by MATLAB simulation results.
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Miao, Guowang. "Cross-layer optimization for spectral and energy efficiency." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31807.

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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2010.
Committee Chair: Li, Geoffrey Ye; Committee Member: Ma, Xiaoli; Committee Member: Stuber, Gordon; Committee Member: Wardi, Yorai; Committee Member: Yu, Xingxing. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Hägg, Ragnar. "Scalable High Efficiency Video Coding : Cross-layer optimization." Thesis, Uppsala universitet, Avdelningen för visuell information och interaktion, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-257558.

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In July 2014, the second version of the HEVC/H.265 video coding standard was announced, and it included the Scalable High efficiency Video Coding (SHVC) extension. SHVC is used for coding a video stream with subset streams of the same video with lower quality, and it supports spatial, temporal and SNR scalability among others. This is used to enable easy adaption of a video stream, by dropping or adding packages, to devices with different screen sizes, computing power and bandwidth. In this project SHVC has been implemented in Ericsson's research encoder C65. Some cross-layer optimizations have also been implemented and evaluated. The main goal of these optimizations are to make better decisions when choosing the reference layer's motion parameters and QP, by doing multi-pass coding and using the coded enhancement layer information from the first pass.
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Soldati, Pablo. "Cross-layer optimization of wireless multi-hop networks." Licentiate thesis, Stockholm Stockholm : Elektrotekniska system, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4463.

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Loretti, Simone. "Cross-layer Optimization of CDMA Multihop Radio Networks." Thesis, KTH, Reglerteknik, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-109471.

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In this thesis, the problem of finding the jointly Scheduling, Power and Rate allocation for Wireless ad hoc networks is considered. The motivation for this study is limiting multiuser interference in order to increase the total utility, throughput, and spatial reuse of the system. One such algorithm is realized for an S-TDMA (Spatial reuse-Time Division Multiple Access) environment where all communication links share the same frequency band and are power limited. Strong levels of interference inherent to wireless ad hoc network can not be overcome by computationally expensive power control algorithm. Therefore a scheduling algorithm becomes essential to coordinate the transmissions of the users in order to guarantee nonconflicting transmission and an efficient spatial reuse. In this work, firstly an algorithm that tries to simultaneously optimize routing, power/rate control and scheduling for a network composed by fixed nodes and channel gain depend only on distances, is developed. Then, with some modifications, the developed procedure handles node mobility and time-varying flat-fading channel. Numerical results indicate that both ones increase the performances of the system. Furthermore a formulation suitable for the study of energy-constrained networks is introduced. Finally this work investigates the use of multiuser detectors (MUD) in an ad hoc network environment. We demonstrate that multiuser detectors in the terminals give substantial improvements to the total network utility, even when we use very simple schemes for scheduling transmissions.
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Lin, Yuxia. "Cross-layer optimization in wireless local area networks." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/7571.

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This thesis studies several research problems in the area of wireless local area networks (WLANs) with an objective of improving network efficiency, quality-of-service and user satisfactions. The I E E E 802.11 Working Group has been under rapid development and expansion in recent years following the successful deployment of the 802.11 network around the globe. The thesis work has been striving to study several key problems in these developments and propose effective schemes to improve network performance. The original 802.11 standard presents a simple and robust design, but has relatively low data rate and lacks QoS support. The recent 802.11e standard and the 8 0 2 . l ln proposals aim to significantly improve the network performance in terms of QoS and throughput. In this thesis, an analytical model of I E E E 802.11e WLANs is first presented. With the help of this throughput model, an admission control scheme for a multi-hop 802.11e W L A N is proposed. To fully utilize the high data rate provided by 802.11n, the performance improvement of the M A C protocol by frame aggregation is studied. Two frame aggregation techniques, namely A - M P D U (MAC Protocol Data Unit Aggregation) and A - M S D U (MAC Service Data Unit Aggregation) are considered. Furthermore, a comprehensive network setup is studied where the QoS requirements of the 802.11e M A C and the MIMO physical layer of 8 0 2 . l ln are both considered. Cross-layer design schemes are proposed for WLANs under two different M A C protocols: the carrier sense multiple access with collision avoidance (CSMA/CA)-based 802.11e M A C , and the slotted Aloha M A C . Lastly, the thesis studies the problem of cooperative transmission in a wireless ad-hoc network with extensions to the 802.11 M A C protocols. A complete system framework is proposed for wireless adhoc networks utilizing two different cooperative relaying techniques at the physical layer: the repetition coding and the space-time coding. In the data link layer, two medium access control protocols are proposed to accommodate the corresponding physical layer cooperative diversity schemes. In the network layer, diversity-aware routing protocols are proposed to determine the routing path and the relaying topology. Improvements in network performance for the proposed schemes are validated with numerical and simulation tests.
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Dubroca, Sabrina Marjorie. "Cross-Layer optimization in a satellite communication network." Thesis, KTH, Radio Systems Laboratory (RS Lab), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-127401.

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This thesis aims to improve a satellite communication network which carries both data streams and Voice over IP (VoIP) communication sessions with resource reservation. The resource reservations are made using the standard protocols for Traffic Engineering: MPLS-TE and RSVP-TE. The goal of this thesis project is to optimize the number of concurrent VoIP calls that can be made, in order to use the available bandwidth while maintaining a guaranteed Quality of Service (QoS) level, which is not possible in the existing system. This thesis proposes and evaluates a solution to this optimization problem in the specific context of a satellite modem system that was developed by Thales Communications. This optimization improves the system's ability to carry VoIP communications through better use of the available transmission resources. A solution to this problem would also increase the  exibility in bandwidth allocation within the modem system, and could provide a framework for future development. The proposed solution allows all of the reservable bandwidth to be used.  The amount of reservable bandwidth must be at least a little lower than the channel's available bandwidth in order to avoid congestion. Some areas of future work are proposed.
Detta projekt har försökt förbättra ett datornätverk bestående av satelliter som används till både data och Voice over IP (VoIP) kommunikation. VoIP använder sig av resursreservation som bestäms av standardprotokollen för Traffic Engineering, MPLS-TE och RSVP-TE.  Målet är att optimera antalet samtidiga VoIP samtal så att det mesta av den befintliga bandbredden kan utnyttjas samtidigt som Quality of Service (QoS) kan garanteras. Detta är omöjligt i det befintliga systemet. Projektet föreslår en lösning för problemet med modemet som utvecklas av Thales Communications och utvärderar därefter lösningen. Dessa optimeringar förbättrar systemets förmåga att driva VoIP kommunikationer genom att bättre använda de befintliga resurserna. En lösning för det här problemet skulle höja systemets flexibilitet och kunna användas som underlag för kommande utvecklingar. Tack vare lösningen kan hela utsedda bandbredden reserveras. Antalet bandbredd som kan reserveras måsta vara minst lite lågre än total befintling bandbredd för att undvika överbelastning. även några möjliga ideer för vidare undersökning föreslås.
Ce projet a pour but d'améliorer un réseau de communication par satellite utilisé pour transporter des flux de données ainsi que des sessions de communication Voix sur IP (VoIP) avec réservation de ressources. Les réservations sont prises en charge par les protocoles standard de Traffic Engineering que sont MPLS-TE et RSVP-TE. L'objectif de ce projet est d'optimiser le nombre d'appels VoIP pouvant être passés en parallèle afin d'utiliser autant de bande passante que possible tout en offrant un niveau de Qualité de Service (QoS) garanti, chose impossible dans le système actuel. Ce rapport propose et évalue une solution à ce problème d'optimisation dans le contexte spécifique du modem satellite développé par Thales Communications. Ces optimisations amélioreraient la capacité du système à transporter des communications VoIP grâce à une meilleure utilisation des ressources disponibles pour la transmission. Une solution à ce problème rendrait aussi l'allocation de ressources plus flexible au sein du système, et pourrait fournir une base à de futurs développements. La solution proposée permet l'utilisation de toute la bande passante réservable. La quantité réservable doit être un peu inférieure à la bande passante totale disponible afin d'éviter la congestion. Les résultats de ces évaluations sont exposés. Enfin, ce rapport propose de futurs développements possibles.
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Books on the topic "Layer by layer optimization"

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Warren, Christopher L. Submarine design optimization using boundary layer control. Springfield, Va: Available from National Technical Information Service, 1997.

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A, Kanibolotskiĭ M., ed. Matematicheskie metody sinteza sloistykh struktur. Novosibirsk: VO "Nauka", 1993.

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Strobel, Rainer. Channel Modeling and Physical Layer Optimization in Copper Line Networks. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-91560-9.

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1966-, Giambene Giovanni, ed. Resource management in satellite networks: Optimization and cross-layer design. New York, N.Y: Springer, 2007.

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Morel, M. Interphase layer optimization for metal matrix composites with fabrication considerations. [Washington, D.C.]: National Aeronautics and Space Administration, 1991.

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1966-, Giambene Giovanni, ed. Resource management in satellite networks: Optimization and cross-layer design. New York, N.Y: Springer, 2007.

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S, Salzar Robert, and United States. National Aeronautics and Space Administration., eds. Optimization of residual stresses in MMC's through the variation of interfacial layer architectures and processing parameters. [Washington, DC]: National Aeronautics and Space Administration, 1996.

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S, Salzar Robert, and United States. National Aeronautics and Space Administration., eds. Optimization of residual stresses in MMC's through the variation of interfacial layer architectures and processing parameters. [Washington, DC]: National Aeronautics and Space Administration, 1996.

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Center, Langley Research, ed. Optimum suction distribution for transition control. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1996.

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Center, Langley Research, ed. Optimum suction distribution for transition control. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1996.

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Book chapters on the topic "Layer by layer optimization"

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Hu, Kai, Krishnendu Chakrabarty, and Tsung-Yi Ho. "Control-Layer Optimization." In Computer-Aided Design of Microfluidic Very Large Scale Integration (mVLSI) Biochips, 25–52. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-56255-1_2.

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Song, Lingyang, Zhu Han, and Chen Xu. "Cross-Layer Optimization." In Resource Management for Device-to-Device Underlay Communication, 51–73. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-8193-5_4.

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Salo, Jari, and Jussi Reunanen. "Inter-layer Mobility Optimization." In LTE Small Cell Optimization, 333–78. Chichester, UK: John Wiley & Sons Ltd, 2015. http://dx.doi.org/10.1002/9781118912560.ch15.

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Marchewka, Adam, and Jarosław Zdrojewski. "Layer Image Components Geometry Optimization." In Advances in Intelligent Systems and Computing, 225–32. Heidelberg: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-01622-1_27.

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Hildmann, H., D. Y. Atia, D. Ruta, K. Poon, and A. F. Isakovic. "Nature-Inspired? Optimization in the Era of IoT: Particle Swarm Optimization (PSO) Applied to Indoor-Distributed Antenna Systems (I-DAS)." In The IoT Physical Layer, 171–92. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-93100-5_11.

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Bi, Ying, Bing Xue, and Mengjie Zhang. "Multi-layer Representation for Binary Image Classification." In Adaptation, Learning, and Optimization, 75–95. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-65927-1_4.

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Chze, Paul Loh Ruen, Kan Siew Leong, Ang Khoon Wee, Elizabeth Sim, Kan Ee May, and Hing Siew Wing. "Cross-Layer Secured IoT Network and Devices." In Proceedings in Adaptation, Learning and Optimization, 319–33. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-13356-0_26.

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Rehman, Semeen, Muhammad Shafique, and Jörg Henkel. "Cross-Layer Reliability Analysis, Modeling, and Optimization." In Reliable Software for Unreliable Hardware, 51–80. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-25772-3_3.

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Syrotiuk, Violet R., and Amaresh Bikki. "Modeling Cross-Layer Interaction Using Inverse Optimization." In Mobile Ad Hoc Networking, 411–25. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2005. http://dx.doi.org/10.1002/0471656895.ch15.

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Yang, Yimin, and Q. M. Jonathan Wu. "Two-Layer Extreme Learning Machine for Dimension Reduction." In Proceedings in Adaptation, Learning and Optimization, 31–42. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-28373-9_3.

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Conference papers on the topic "Layer by layer optimization"

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Bien, Anna. "Optimization of laser-modified surface layer homogeneity." In Laser Technology V: Applications in Materials Sciences and Engineering. SPIE, 1997. http://dx.doi.org/10.1117/12.287835.

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Zhang, Jiaqiang, Quan Liu, Wenjun Xu, Zude Zhou, and Duc Truong Pham. "Cross-Layer Optimization Model Towards Service-Oriented Robotic Manufacturing Systems." In ASME 2017 12th International Manufacturing Science and Engineering Conference collocated with the JSME/ASME 2017 6th International Conference on Materials and Processing. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/msec2017-2703.

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Service-oriented robotic manufacturing system is an integrated system, in which the industrial robots (IRs) operate within a service-oriented manufacturing model, and can be virtualized and servicelized as services, so as to provide on-demand, agile, configurable and sustainable manufacturing capability services to users in workshop environment. Manufacturing capability of such systems can be divided into three layers, including manufacturing cell layer, production process layer and workshop layer. However, most of existing works carried out the optimization on each layer individually. Manufacturing cells are the component parts of a production process, and there are close relationships between them and can effect the operation and performance for each other, therefore it is essential to jointly consider the manufacturing capability service optimization on both layers. In this context, a cross-layer optimization model is proposed to conquer the existing limitation and provide a comprehensive performance assurance to service-oriented robotic manufacturing systems. The proposed model has different decision-making mechanisms on each layer and the communications and interaction between the two layers can further coordinate the optimizations. A case study based on robotic assembly is implemented to demonstrate the availability and effectiveness of the proposed model.
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Chen, Jack Szu-Shen, and Hsi-Yung Steve Feng. "Tolerance-Based Layer Setup Optimization for Layered Manufacturing." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-37775.

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This paper introduces a new tolerance-based method to generate the optimum layer setup required to build layered manufacturing (LM) end-user parts for maximized efficiency. To achieve this, the deviation between the final polished LM part geometry and the original design model are formulated and controlled. Maximized layer thicknesses are then realized through optimization of each layer position with respect to the design and final geometry and maximization of the allowable deviation for each layer, which consequently leads to minimization of the build time. Current LM layer setup methods do not take into account of the final part during layer setup generation, rendering layer thickness selection to operator-deemed-best. Without the ability to predict the final geometry and to optimize the layer setup accordingly, layer thickness selection is often overly conservative, causing more layers than necessary to be used. Since the LM build time increases exponentially with an increase in the number of layers, efficiency is greatly reduced with conservative layer setup. To achieve maximum efficiency, this paper proposes a new method based on error compensation and minimization to solve for the optimum layer setup necessary to allow the resulting final physical part to reliably approximate the design model geometry according to a user specified tolerance limit. Case studies have been performed in order to validate that the proposed method is able to minimize the number of layers for constructing an LM part while controlling the maximum error for tolerance conformance.
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Moser, Daniel, Scott Fish, Joseph Beaman, and Jayathi Murthy. "Multi-Layer Computational Modeling of Selective Laser Sintering Processes." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-37535.

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Selective laser sintering (SLS) is an additive manufacturing technique able to rapidly create parts directly from a CAD model using a laser to selectively fuse successive layers of powder. However, defects can arise in SLS parts due to incomplete fusion of the powder layers or thermal stresses introduced by large temperature gradients during the part build. Accurate models of the SLS process are needed to ensure that high quality parts are produced and to allow new materials and designs to be used without requiring extensive experimentation. Most existing models of the SLS process are very narrowly focused, predicting the temperature history of a single powder layer after a single laser pass or examining the impact of a few processing parameters on the properties of the produced part. A model capable of predicting a complete temperature history during an entire part build does not yet exist. Therefore, a new thermal model able to simulate multiple powder layers is proposed. A transient, three-dimensional, finite volume model is developed and implemented in ANSYS Fluent. A domain of cells representing multiple layers of an SLS build is initialized, some with the properties of air and some with the properties of powder, depending on cell location. A Gaussian heat source representing the laser is applied to the top layer of powder cells. The center of the Gaussian is varied with time along an established path to simulate the motion of the laser along the powder bed. At all times the three-dimensional heat equation is solved to produce a temperature profile of the powder bed. When the laser completes a full scan of the powder layer, the air cells directly above the powder layer are re-initialized as powder cells and re-set to an initial temperature, representing the addition of a new powder layer. The process is repeated for each new layer. Temperature history results from the model are validated against experimental data available in the literature and good agreement is obtained. As the model accounts for multiple powder layers, it can be used to simulate an entire part build and predict the impact of any of the SLS processing parameters on part quality and thus enable better control and optimization of the SLS process.
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Ghiasi, Hossein, Damiano Pasini, and Larry Lessard. "Layer Separation for Optimization of Composite Laminates." In ASME 2008 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/detc2008-50106.

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The excellent mechanical properties of laminated composites cannot be exploited without a careful design of stacking sequence of the layers. An important variable in the search of the optimum stacking sequence is the number of layers. The larger is this number, the harder as well as longer is the search for an optimal solution. To tackle efficiently such a variable-dimensional problem, we introduce here a multi-level optimization technique. The proposed method, called Layer Separation (LS), increases or decreases the number of layers by gradually separating a layer into two, or by merging two layers into one. LS uses different levels of laminate representation ranging from a coarse level parameterization, which corresponds to a small number of thick layers, to a fine level parameterization, which corresponds to a large number of thin layers. A benefit of such differentiation is an increase of the probability of finding the global optimum. In this paper, LS is applied to the design of composite laminates under single and multiple loadings. The results show that LS convergence rate is not inferior to that of other optimization techniques available in the literature. It is faster than an evolutionary algorithm, more efficient than a layerwise method, simple to perform, and it has the advantage of possibility of termination at any point during the optimization process.
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Lan, Weixian, and Julian Panetta. "Efficient Layer-by-Layer Simulation for Topology Optimization." In SCF '22: Symposium on Computational Fabrication. New York, NY, USA: ACM, 2022. http://dx.doi.org/10.1145/3559400.3562000.

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Inoue, Yukari, Matej Hala, Alexander Steigert, Reiner Klenk, and Susanne Siebentritt. "Optimization of buffer layer/i-layer band alignment." In 2015 IEEE 42nd Photovoltaic Specialists Conference (PVSC). IEEE, 2015. http://dx.doi.org/10.1109/pvsc.2015.7355902.

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Sun, Yunlong. "Interference effect on laser trimming and layer thickness optimization." In Proc Int 91, edited by Bodil Braren. SPIE, 1991. http://dx.doi.org/10.1117/12.51029.

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Soumplis, P., P. Pananikolaou, K. Christodoulopoulos, N. Argyris, C. Spatharakis, S. Dris, H. Avramopoulos, and E. Varvarigos. "Cross-layer optimization: Network cost vs. physical layer margins." In 2015 17th International Conference on Transparent Optical Networks (ICTON). IEEE, 2015. http://dx.doi.org/10.1109/icton.2015.7193690.

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Saul, Andreas, and Gunther Auer. "Analysis of Cross-Layer Optimization between Application and Link Layer." In 2007 4th International Symposium on Wireless Communication Systems. IEEE, 2007. http://dx.doi.org/10.1109/iswcs.2007.4392459.

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Reports on the topic "Layer by layer optimization"

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Previdi, S., M. Stiemerling, R. Woundy, and Y. Yang. Application-Layer Traffic Optimization (ALTO) Requirements. Edited by S. Kiesel. RFC Editor, September 2012. http://dx.doi.org/10.17487/rfc6708.

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Kiesel, S., S. Previdi, W. Roome, S. Shalunov, and R. Woundy. Application-Layer Traffic Optimization (ALTO) Protocol. Edited by R. Alimi, R. Penno, and Y. Yang. RFC Editor, September 2014. http://dx.doi.org/10.17487/rfc7285.

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Seedorf, J., and E. Burger. Application-Layer Traffic Optimization (ALTO) Problem Statement. RFC Editor, October 2009. http://dx.doi.org/10.17487/rfc5693.

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Kiesel, S., M. Stiemerling, N. Schwan, M. Scharf, and H. Song. Application-Layer Traffic Optimization (ALTO) Server Discovery. RFC Editor, November 2014. http://dx.doi.org/10.17487/rfc7286.

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Stiemerling, M., S. Kiesel, M. Scharf, H. Seidel, and S. Previdi. Application-Layer Traffic Optimization (ALTO) Deployment Considerations. RFC Editor, October 2016. http://dx.doi.org/10.17487/rfc7971.

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Randriamasy, S., W. Roome, and N. Schwan. Multi-Cost Application-Layer Traffic Optimization (ALTO). RFC Editor, October 2017. http://dx.doi.org/10.17487/rfc8189.

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Randriamasy, S., R. Yang, Q. Wu, L. Deng, and N. Schwan. Application-Layer Traffic Optimization (ALTO) Cost Calendar. RFC Editor, November 2020. http://dx.doi.org/10.17487/rfc8896.

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Wu, Q., Y. Yang, Y. Lee, D. Dhody, S. Randriamasy, and L. Contreras. Application-Layer Traffic Optimization (ALTO) Performance Cost Metrics. RFC Editor, August 2023. http://dx.doi.org/10.17487/rfc9439.

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Kiesel, S., and M. Stiemerling. Application-Layer Traffic Optimization (ALTO) Cross‑Domain Server Discovery. RFC Editor, February 2020. http://dx.doi.org/10.17487/rfc8686.

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Maurer, Scott M., David L. Fowler, and David K. Friday. Optimization and Measurement of Water Removal on a Laboratory Scale-PSA System; Summary Report: 13X, 3-Layer, 4-Layer, and 5-Layer PSA Beds. Fort Belvoir, VA: Defense Technical Information Center, November 1997. http://dx.doi.org/10.21236/ada333299.

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