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Journal articles on the topic 'Maximum ratio combiner'

Author: Grafiati

Published: 4 September 2021

Last updated: 11 February 2022

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Djeumou, Brice, Samson Lasaulce, and Antoine O. Berthet. "Combining Coded Signals with Arbitrary Modulations in Orthogonal Relay Channels." Research Letters in Communications 2008 (2008): 1–4. http://dx.doi.org/10.1155/2008/287320.

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We consider a relay channel for which the following assumptions are made. (1) The source-destination and relay-destination channels are orthogonal (frequency division relay channel). (2) The relay implements the decode-and-forward protocol. (3) The source and relay implement the same channel encoder, namely, a convolutional encoder. (4) They can use arbitrary and possibly different modulations. In this framework, we derive the best combiner in the sense of the maximum likelihood (ML) at the destination and the branch metrics of the trellis associated with its channel decoder for the ML combiner and also for the maximum ratio combiner (MRC), cooperative-MRC (C-MRC), and the minimum mean-square error (MMSE) combiner.

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Ivanis, P., V. Blagojevic, D. Drajic, and B. Vucetic. "Second-order statistics of a maximum ratio combiner with unbalanced and unequally distributed Nakagami branches." IET Communications 5, no. 13 (2011): 1829–35. http://dx.doi.org/10.1049/iet-com.2010.0493.

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Parrish, Nathan H., Ashley J. Llorens, and Alex E. Driskell. "An Agent-Ensemble for Thresholded Multi-Target Classification." Applied Sciences 10, no. 4 (2020): 1376. http://dx.doi.org/10.3390/app10041376.

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We propose an ensemble approach for multi-target binary classification, where the target class breaks down into a disparate set of pre-defined target-types. The system goal is to maximize the probability of alerting on targets from any type while excluding background clutter. The agent-classifiers that make up the ensemble are binary classifiers trained to classify between one of the target-types vs. clutter. The agent ensemble approach offers several benefits for multi-target classification including straightforward in-situ tuning of the ensemble to drift in the target population and the ability to give an indication to a human operator of which target-type causes an alert. We propose a combination strategy that sums weighted likelihood ratios of the individual agent-classifiers, where the likelihood ratio is between the target-type for the agent vs. clutter. We show that this combination strategy is optimal under a conditionally non-discriminative assumption. We compare this combiner to the common strategy of selecting the maximum of the normalized agent-scores as the combiner score. We show experimentally that the proposed combiner gives excellent performance on the multi-target binary classification problems of pin-less verification of human faces and vehicle classification using acoustic signatures.

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Ali, M., M. A. K. Mian, M. A. Hossain, M. Z. Islam, and M. M. Hossain. "COMBINING ABILITY AND HETEROSIS IN QUASI AROMATIC RICE (Oryza sativa L.)." Bangladesh Journal of Plant Breeding and Genetics 27, no. 1 (2015): 1–8. http://dx.doi.org/10.3329/bjpbg.v27i1.23971.

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The experiment was conducted to study general and specific combining ability (GCA and SCA) and to estimate heterosis estimation at experimental farm of Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur during T. Aman, 2006 and 2007 seasons. Eleven rice parental lines consisting of two quasi CMS lines in BC3 generation as lines and nine restorer lines as testers along with their eighteen F1s and a check variety (BRRI dhan37) were used for combining ability study in a line x tester mating design for eight characters. Ratio of general combining ability (GCA) to specific combining ability (SCA) variances above unity were observed for 1000-grain weight(g) indicating predominance of additive gene action for controlling the character. Among mother parents, CMS-1 appeared as good general combiner for panicle length, 1000-grain weight(g), and grain lengthbreadth ratio. Among male parents, Benaful, Oval Tapi and Sorukamini-1 were observed to be good general combiners for most of the characters studied. The cross combinations, CMS-1 × Kataribhog, CMS-2 × Maloti-1 and CMS-2 × Keora were found as good specific combiners for most of the characters under study. Good specific combiners were evolved from all kinds of combinations of general combiners indicating additive and non-additive types of gene effect for inheritance. Maximum hybrids showed desired significant standard heterosis for panicle length and 1000-grain weight. None of the hybrids showed desired and significant standard heterosis simultaneously for any three or more characters.

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Gahtyari, Navin Chander, P. I. Patel, Rakesh Choudhary, Sudhir Kumar, Naveen Kumar, and J. P. Jaiswal. "Combining ability studies for yield, associated traits and quality attributes in rice for South Gujarat (Oryza sativa L.)." Journal of Applied and Natural Science 9, no. 1 (2017): 60–67. http://dx.doi.org/10.31018/jans.v9i1.1151.

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Line x tester analysis using a set of four females, ten males and their forty hybrids was carried out to esti-mate the general combining ability of parents and specific combining ability of hybrids for yield and ten other associ-ated components in rice (Oryza sativa L.) in a Randomized Block Design during Kharif 2011. GCA variances for females (s2f) were significant at 0.1% level of significance for plant height (40.8), no. of grains per panicle (505.9), grain yield per plant (29.1), test weight(17.9), straw yield per plant (61.3) and kernel L/B ratio (0.2) whereas specific combining ability (SCA) variances for f x m interactions were highly significant for all the characters. Non-additive gene action was prevalent in all characters (Range: 0.03 in amylose content to 0.88 in kernel length breadth ratio) except plant height (1.33) as evident by low GCA to SCA ratio. None of the parents were good general combiner for all traits, however, female IR-28 and male AMT-119 and PNR-546 were good general combiners for a maximum number of traits i.e. five traits out of eleven.. The general combining ability for grain yield per plant for female parent Gurjari (6.19) and NVSR-178 (5.29); and male parents AMT 119 (2.73) and PNR 546 (2.44) makes them a good choice for improving yields in a hybridization programme as these female and male parents are also having signifi-cant GCA effects for maximum number of yield associated traits i.e. four and five traits out of eleven for female and male parents respectively. A vis-à-vis comparison of top three specific combining ability crosses with their mean performance showed correlation and these crosses were having at least one good general combining ability parent.

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Marques da Silva, Mário, and Rui Dinis. "Power-Ordered NOMA with Massive MIMO for 5G Systems." Applied Sciences 11, no. 8 (2021): 3541. http://dx.doi.org/10.3390/app11083541.

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The aim of this article is to study the conventional and cooperative power-order Non-Orthogonal Multiple Access (NOMA) using the Single Carrier with Frequency Domain Equalization (SC-FDE) block transmission technique, associated with massive Multiple-Input Multiple-Output (MIMO), evidencing its added value in terms of spectral efficiency of such combined scheme. The new services provided by Fifth Generation of Cellular Communications (5G) are supported by new techniques, such as millimeter waves (mm-wave), alongside the conventional centimeter waves and by massive MIMO (m-MIMO) technology. NOMA is expected to be incorporated in future releases of 5G, as it tends to achieve a capacity gain, highly required for the massive number of Internet of things (IoT) devices, namely to support an efficient reuse of limited spectrum. This article shows that the combination of conventional and cooperative NOMA with m-MIMO and SC-FDE, tends to achieve capacity gains, while the performance only suffers a moderate degradation, being an acceptable alternative for future evolutions of 5G. Moreover, it is shown that Cooperative NOMA tends to outperform Conventional NOMA. Moreover, this article shows that the Maximum Ratio Combiner (MRC) receiver is very well fitted to be combined with NOMA and m-MIMO, as it achieves a good performance while reducing the receiver complexity.

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Gvozdarev, Aleksey, and Pavel Patralov. "PROBABILISTIC ANALYSIS OF GENERALISED STATISTIC MODEL FOR MULTIPATH CHANNEL OF SIMO SISTEMS WITH FADING AND CORRELATED SHADOWING." Informatics and Automation 20, no. 3 (2021): 727–49. http://dx.doi.org/10.15622/ia.2021.3.8.

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The paper considers the problem of analysis of the information transmission process by multi-element communication systems in presence of a multipath signal propagation channel. To generalize the propagation effects, the model of the κ–μ fading channel with correlated shadowing was assumed, and the technology used for organizing a multi-element system was the SIMO system, equipped with the maximum-ration combiner of the signal on the receiving side. To describe the characteristics of the information transfer process, an approach based on the higher-order statistics of the ergodic capacity was used. Closed-form analytical expressions for arbitrary-order capacity higher-order statistics were obtained for the channel model under consideration. The behavior of the first four statistics (ergodic capacity, its reliability, skewness and kurtosis coefficients) is analyzed depending on the channel parameters (the number of multipath propagation clusters, the ratio of power of the dominant components to the total power of multipath waves, the degree of shadowing of the dominant components, and the shadowing correlation coefficient). Within the framework of the study, 4 distinct situations of the assumed channel model behavior were considered, which significantly differ in their properties. It is noted that, in contrast to the capacity, its higher-order statistics are significantly more sensitive to the channel parameters and, as a result, are more significant indicators of fluctuations in the information transfer rate within the communication channel. The existence of a pronounced extremum (minimum) of the reliability ergodic capacity dependence from the signal-to-noise ratio was established. It should be accounted for in practical applications, when the requirements of the signal-to-noise ratio that guarantees the desired communication link quality are set.

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Kabalci, Yasin, and Muhammad Ali. "Improved Hybrid Precoder Design for Secure mmWave MIMO Communications." Elektronika ir Elektrotechnika 26, no. 4 (2020): 72–77. http://dx.doi.org/10.5755/j01.eie.26.4.25857.

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Key challenges of emerging mobile communication systems are to provide higher data rates, diverse device connectivity, low latency, higher system capacity, and low energy consumption. The communication systems exploiting the millimeter-wave (mmWave) band are realized to resolve thereof inevitable issues. However, security is considered as one of the challenging issues in mmWave communication in addition to unavoidable problems (e.g., propagation loss, penetration loss, and fading). This study aims to construct efficient secure hybrid precoder with low-resolution phase shifters that can protect legitimate information from eavesdropping by employing coordinated analog precoder and combiner algorithms and improve the secrecy rate. Moreover, in order to further enhance the secrecy rate, hybrid precoder are obtained using an efficient channel. This work compares its results with the recent approach reported in the literature, which indicates that our proposed model outperforms at high signal-to-noise ratio (SNR) values, while our model provides similar performance at low SNR values. Simulation studies also confirm the effectiveness of the proposed hybrid precoder to achieve maximum secrecy rate.

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Navitha, Ch, K. Sivani, and K. Ashoka Reddy. "Performance Evaluation of Adaptive Continuous Wavelet Transform based Rake Receiver for UWB Systems." International Journal of Electrical and Computer Engineering (IJECE) 8, no. 5 (2018): 3444. http://dx.doi.org/10.11591/ijece.v8i5.pp3444-3452.

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This paper proposes an adaptive continuous wavelet transform (ACWT) based Rake receiver to mitigate interference for high speed ultra wideband (UWB) transmission. The major parts of the receiver are least mean square (LMS) adaptive equalizer and N-selective maximum ratio combiner (MRC). The main advantage of using continuous wavelet rake receiver is that it utilizes the maximum bandwidth (7.5GHz) of the UWB transmitted signal, as announced by the Federal Communication Commission (FCC). In the proposed ACWT Rake receiver, the weights and the finger positions are updated depending upon the convergence error over a period in which training data is transmitted. Line of sight (LOS) channel model (CM1 from 0 to 4 meters) and the Non line of sight (NLOS) channel models (CM, CM3 and CM4) are the indoor channel models selected for investigating in this research . The performance of the proposed adaptive system is evaluated by comparing with conventional rake and continuous wavelet transform (CWT) based rake. It showed an improved performance in all the different UWB channels (CM1 to CM4) for rake fingers of 2, 4 and 8. Simulations showed that for 8 rake fingers, the proposed adaptive CWT rake receiver has shown an SNR improvement of 2dB, 3dB, 10dB and 2dB respectively over CWT rake receiver in different UWB channels CM1, CM2, CM3 and CM4.

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Yu, Yi, Lina Mroueh, Philippe Martins, Guillaume Vivier, and Michel Terré. "Radio Resource Dimensioning for Low Delay Access in Licensed OFDMA IoT Networks." Sensors 20, no. 24 (2020): 7173. http://dx.doi.org/10.3390/s20247173.

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In this paper, we focus on the radio resource planning in the uplink of licensed Orthogonal Frequency Division Multiple Access (OFDMA) based Internet of Things (IoT) networks. The average behavior of the network is considered by assuming that active sensors and collectors are distributed according to independent random Poisson Point Process (PPP) marked by channel randomness. Our objective is to statistically determine the optimal total number of Radio Resources (RRs) required for a typical cell. On one hand, the allocated bandwidth should be sufficiently large to support the traffic of the devices and to guarantee a low access delay. On the other hand, the over-dimensioning is costly from an operator point of view and induces spectrum wastage. For this sake, we propose statistical tools derived from stochastic geometry to evaluate, adjust and adapt the allocated bandwidth according to the network parameters, namely the required Quality of Service (QoS) in terms of rate and access delay, the density of the active sensors, the collector intensities, the antenna configurations and the transmission modes. The optimal total number of RRs required for a typical cell is then calculated by jointly considering the constraints of low access delay, limited power per RR, target data rate and network outage probability. Different types of networks are considered including Single Input Single Output (SISO) systems, Single Input Multiple Output (SIMO) systems using antenna selection or Maximum Ratio Combiner (MRC), and Multiuser Multiple Input Multiple Output (MU-MIMO) systems using Zero-Forcing decoder.

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Fayadh, Rashid A., F. Malek, and Hilal A. Fadhil. "Pulse Sign Separation Technique for the Received Bits in Wireless Ultra-Wideband Combination Approach." Mathematical Problems in Engineering 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/919681.

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When receiving high data rate in ultra-wideband (UWB) technology, many users have experienced multiple-user interference and intersymbol interference in the multipath reception technique. Structures have been proposed for implementing rake receivers to enhance their capabilities by reducing the bit error probability (Pe), thereby providing better performances by indoor and outdoor multipath receivers. As a result, several rake structures have been proposed in the past to reduce the number of resolvable paths that must be estimated and combined. To achieve this aim, we suggest two maximal ratio combiners based on the pulse sign separation technique, such as the pulse sign separation selective combiner (PSS-SC) and the pulse sign separation partial combiner (PSS-PC) to reduce complexity with fewer fingers and to improve the system performance. In the combiners, a comparator was added to compare the positive quantity of positive pulses and negative quantities of negative pulses to decide whether the transmitted bit was 1 or 0. ThePewas driven by simulation for multipath environments for impulse radio time-hopping binary phase shift keying (TH-BPSK) modulation, and the results were compared with those of conventional selective combiners (C-SCs) and conventional partial combiners (C-PCs).

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Chen, Jie Shi, and Jun Chen. "Sheet Metal Forming Limit Prediction with Maximum Thickness Reduction Ratio." Advanced Materials Research 314-316 (August 2011): 999–1004. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.999.

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Maximum thickness reduction ratio is used to predict sheet metal forming limit in the numerical simulation of forming process. The maximum thickness reduction ratio under different stain path is not a constant for the same material. The effect of strain path and strain hardening exponent on forming limit is considered. The relationship between the maximum thickness reduction ratio that the material can obtained and the strain path between tensile to equi-biaxial is established. The parameter in the criterion can be determined by tensile experiment combined with numerical simulation of the same forming process. Then the limit strains under other linear strain paths between tensile to equi-biaxial can be determined by the criterion combined with numerical simulation of corresponding forming process. Forming limits of three kinds of sheet metals are predicted with the modified maximum thickness reduction ratio criterion. Good agreement is achieved between the predicted data and the experimental data.

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Horlock, J. H. "The Optimum Pressure Ratio for a Combined Cycle Gas Turbine Plant." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 209, no. 4 (1995): 259–64. http://dx.doi.org/10.1243/pime_proc_1995_209_004_01.

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A graphical method of calculating the performance of gas turbine cycles, developed by Hawthorne and Davis (1), is adapted to determine the pressure ratio of a combined cycle gas turbine (CCGT) plant which will give maximum overall efficiency. The results of this approximate analysis show that the optimum pressure ratio is less than that for maximum efficiency in the higher level (gas turbine) cycle but greater than that for maximum specific work in that cycle. Introduction of reheat into the higher cycle increases the pressure ratio required for maximum overall efficiency.

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El-Mahdy, Ahmed El-Sayed. "EM-Based Optimal Maximal Ratio Diversity Combiner for Constant Envelope Signals." Open Signal Processing Journal 2, no. 1 (2009): 1–6. http://dx.doi.org/10.2174/1876825300902010001.

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Iskander, C. D., and P. T. Mathiopoulos. "Analytical Envelope Correlation and Spectrum of Maximal-Ratio Combined Fading Signals." IEEE Transactions on Vehicular Technology 54, no. 1 (2005): 399–404. http://dx.doi.org/10.1109/tvt.2004.838889.

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Annamalai, A., and C. Tellambura. "Analysis of hybrid selection/maximal-ratio diversity combiners with Gaussian errors." IEEE Transactions on Wireless Communications 1, no. 3 (2002): 498–512. http://dx.doi.org/10.1109/twc.2002.800548.

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El Haj Assad, Mamdouh. "Finite-Time Thermodynamic Analysis of Combined Heat Engines." International Journal of Mechanical Engineering Education 25, no. 4 (1997): 281–89. http://dx.doi.org/10.1177/030641909702500404.

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The maximum power output and the efficiency at that power of a combined heat engines are analysed by using Curzon and Ahlborn's finite-time analysis. The efficiency at the maximum power of the combined reversible and irreversible heat engines has been obtained. This work also shows that when the engines are internally irreversible, the combined cycle delivers less power and has lower efficiency than an endoreversible combined heat engines. An expression is derived to relate the maximum power output ratio (irreversible/endoreversible) to the corresponding cycle efficiency ratio. It is shown by that relation that the efficiency ratio is much higher than the power ratio and they become identical when the irreversible cycle is very close to the endoreversible one.

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Yan, Yi, and Rui-jin Li. "Maximum likelihood channel estimation algorithm combines logarithm likelihood ratio decoding in the coal mine application." Journal of Coal Science and Engineering (China) 19, no. 1 (2013): 104–8. http://dx.doi.org/10.1007/s12404-013-0117-4.

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Milišić, Mirza, Mirza Hamza, and Mesud Hadžialić. "BEP/SEP and Outage Performance Analysis of -Branch Maximal-Ratio Combiner for Fading." International Journal of Digital Multimedia Broadcasting 2009 (2009): 1–8. http://dx.doi.org/10.1155/2009/573404.

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Maximal-ratio combiner (MRC) performances in fading channels have been of interest for a long time, which can be seen by a number of papers concerning this topic. In this paper we treat bit error probability (BEP), symbol error probability (SEP) and outage probability of MRC in presence of fading. We will present fading model, probability density function (PDF), and cumulative distribution function (CDF). We will also present PDF, CDF, and outage probability of theL-branch MRC output. BEP/SEP will be evaluated for broad class of modulation types and for coherent and noncoherent types of detection. BEP/SEP and outage performances of the MRC will be evaluated for different number of branches via Monte Carlo simulations and theoretical expressions.

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du Pin Calmon, Flavio, and Michel Yacoub. "MRCS -- selecting maximal ratio combined signals: a practical hybrid diversity combining scheme." IEEE Transactions on Wireless Communications 8, no. 7 (2009): 3425–29. http://dx.doi.org/10.1109/twc.2009.080949.

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Sagias, Nikos C., Anthony C. Boucouvalas, Kostas Yiannopoulos, Murat Uysal, and Zabih Ghassemlooy. "Optimal Combiners in Pre-Amplified Optical Wireless Systems under Medium-to-Strong Atmospheric Turbulence." Image Processing & Communications 21, no. 1 (2016): 25–34. http://dx.doi.org/10.1515/ipc-2016-0002.

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Abstract In this work we analytically investigate optimal combiners for pre-amplified diversity receivers that operate under medium-to-strong atmospheric turbulence. We first demonstrate that the combiner performance is strongly affected by the existence of a signal-amplified spontaneous emission beat noise at the output of the photodetector. Due to the signal-dependent nature of noise, the optimal combiner can be classified as a hybrid one, of which performance is between the well-known equal-gain and maximal-ratio combiner architectures. Having established the optimal design, we further assess the proposed combiner performance over gamma-gamma and negative-exponential fading environments.

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Hu, Ruichang, and Jianmin Zhang. "Numerical Analysis on Hydraulic Characteristics of U-shaped Channel of Various Trapezoidal Cross-Sections." Water 10, no. 12 (2018): 1788. http://dx.doi.org/10.3390/w10121788.

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Curved channel with trapezoidal cross-section is approximate to the common form in nature fluvial networks and its hydraulic characteristics are considerably complex and variable. Combined with volume of fluid (VOF) method, renormalization group (RNG) k-ε turbulence model was employed to numerically investigate the flow properties in the U-shaped channel with various trapezoidal cross-sections. Analyses were performed from the aspects of the water surface transverse slope in bend apex (WTS-BA), longitudinal velocity, secondary flow, shear stress and turbulent kinetic energy (TKE) under several scenarios, specifically, four types of radius-to-width ratio and seven types of slope coefficient with a constant aspect ratio. The calculated results suggested that the maximums of shear stress and TKE in the bend were observed in the convex bank and the maximal intensities of secondary flow were observed within the range of 60 to 75 degrees for various varieties. As the radius-to-width ratio increased, the maximums of shear stress, TKE and WTS-BA decreased; but increased with increasing slope coefficients. The intensity of secondary flow decreased as slope coefficients increased and the angle of maximum intensity of secondary flow moved to the upstream for the increasing radius-to-width ratios. In addition, a new equation concerning the vertical distribution of longitudinal velocity in trapezoidal cross-sectioned channel was presented.

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Hu, Yujia, and Xiaofeng Tao. "Secrecy Outage on Transmit Antenna Selection With Weighting Errors at Maximal-Ratio Combiners." IEEE Communications Letters 19, no. 4 (2015): 597–600. http://dx.doi.org/10.1109/lcomm.2015.2394786.

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ARYANTA, DWI, and RIENZY PRATAMA LONDONG ALLO. "Dynamic Spatial Diversity Combiner pada Kanal Fading." ELKOMIKA: Jurnal Teknik Energi Elektrik, Teknik Telekomunikasi, & Teknik Elektronika 7, no. 3 (2019): 466. http://dx.doi.org/10.26760/elkomika.v7i3.466.

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ABSTRAKKanal transmisi radio berkontribusi pada terjadinya efek fading yang dapat berpengaruh pada terjadinya penurunan kualitas sinyal pada penerima. Salah satu solusi yang digunakan untuk menekan efek fading adalah penggunaan Spatial Diversity di sisi penerima. Pada penelitian ini digunakan suatu teknik Dynamic Spatial Diversity Combining yang memadukan Selection Combining, Equal Gain Combining, dan Maximal Ratio Combining untuk mendapatkan kinerja combiner yang lebih efektif dan efisien. Simulasi dilakukan dengan menggunakan modulasi BPSK pada beberapa jenis kanal yaitu Rayleigh, Rician, Nakagami-m, Weibull, dan Suzuki. Hasil simulasi MATLAB menunjukkan bahwa secara umum kanal yang mendapatkan perbaikan kinerja penerimaan, dimana nilai terendah sebesar 2 dB terjadi pada kanal Suzuki dan tertinggi sebesar 4 dB pada kanal Weibull.Kata kunci: fading, spatial diversity, rayleigh, rician, weibull, nakagami, suzuki. ABSTRACTRadio transmission channels contribute to the occurrence of fading effects that can affect the decrease in signal quality at the receiver. One solution that is used to suppress fading effects is the use of Spatial Diversity on the receiving side. In this research, a Dynamic Spatial Diversity Combining technique is used which combines Selection Combining, Equal Gain Combining, and Maximal Ratio Combining to get a more effective and efficient combiner performance. Simulation is done using BPSK modulation on several types of canals, namely Rayleigh, Rician, Nakagamim, Weibull, and Suzuki. The MATLAB simulation results show that in general canals that get improved performance, where the lowest value of 2 dB occurs on the Suzuki channel and the highest is 4 dB on the Weibull canal.Keywords: fading, spatial diversity, rayleigh, rician, weibull, nakagami, suzuki.

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Cui, X. W., Q. T. Zhang, and Z. M. Feng. "Outage Performance for Maximal Ratio Combiner in the Presence of Unequal-Power Co-Channel Interferers." IEEE Communications Letters 8, no. 5 (2004): 289–91. http://dx.doi.org/10.1109/lcomm.2004.827401.

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Koga, Masafumi, Akira Mizutori, and Tadashi Iida. "Optical diversity transmission and maximum-ratio combined receiver in multi-core fiber to mitigate fiber non-linear phenomenon." IEICE Communications Express 2, no. 2 (2013): 67–73. http://dx.doi.org/10.1587/comex.2.67.

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Nag, P. K., and S. De. "Study of thermodynamic performance of an integrated gasification combined cycle power plant." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 212, no. 2 (1998): 89–95. http://dx.doi.org/10.1243/0957650981536619.

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Computational analysis is performed to investigate the effects of the pressure ratio of the gas cycle (Rp) and the temperature ratio across the combustion chamber (RT) on the thermodynamic performance of an integrated gasification combined cycle (IGCC) power plant with single pressure power generation for both the gas and steam cycles. The gases are assumed to be real ones that follow the Redlich-Kwong equation of state. The overall efficiency of the cycle (η) is found to be maximum at an optimum pressure ratio of the gas cycle for a given temperature ratio. The second law analysis indicates that maximum exergy is destroyed in the process of gasification and is not at all affected by the temperature ratio, while the effect of the pressure ratio on it is also not very significant. The exergy loss in the combustor is found to decrease with an increase in either of the ratios. For the heat recovery steam generator (HRSG), it increases with a higher temperature ratio and decreases with a higher pressure ratio. The total exergy loss of the cycle is found to decrease with either of these two ratios while the other is held constant.

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Reig, Juan. "Performance of maximal ratio combiners over correlated Nakagami-m fading channels with arbitrary fading parameters." IEEE Transactions on Wireless Communications 7, no. 5 (2008): 1441–44. http://dx.doi.org/10.1109/twc.2008.060129.

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Qin, Jun, Yuansheng Tao, Haowen Shu, et al. "Highly Reliable Transmission System for Next-Generation Optical Access Network Based on Silicon Modulator With Maximum-Ratio Combined Receiver." IEEE Journal of Selected Topics in Quantum Electronics 27, no. 3 (2021): 1–10. http://dx.doi.org/10.1109/jstqe.2020.3021732.

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Han, Ji-ang, Jian Guan, Jingjun Zhong, and Zi-an Zhao. "Numerical investigation of strake profile and maximum thickness position in the ram-rotor." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 233, no. 15 (2019): 5773–87. http://dx.doi.org/10.1177/0954410019859703.

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Numerical investigation of ram-rotors with different strake profiles and maximum thickness positions has been performed. Four types of strake profiles are modeled firstly and the results show that total pressure ratio and adiabatic efficiency of the ss-sym, ss-ps, and ss-ss schemes are improved in different degrees compared with the sym-sym scheme, in which the comprehensive performance of the ss-ss scheme is relatively optimal, and its total pressure ratio and adiabatic efficiency are increased by 26.275% and 2.554%, respectively. The results of different strake maximum thickness positions indicate that the total pressure ratio and adiabatic efficiency are gradually increasing with the backward movement of starting point of maximum thickness, and the pressure rising capacity can come to a peak value. As the ending point of maximum thickness moves backward, there both exist peak values of the total pressure ratio and adiabatic efficiency. Compared with the ss-ss scheme, the scheme that combines optimal starting and ending point positions of maximum thickness takes advantage of these two schemes to achieve a higher aerodynamic performance, with total pressure ratio and adiabatic efficiency increasing 0.182% and 1.928%, respectively. Moreover, in comparison to the original sym-sym scheme, the total pressure ratio and the adiabatic efficiency of the combination scheme are improved much by 26.50% and 4.53%.

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D., Damodaram. "MIMO Based Cooperative Communication and Joint Maximum-Likelihood Detection for Cognitive Radio System." International Journal of Recent Technology and Engineering 10, no. 1 (2021): 39–43. http://dx.doi.org/10.35940/ijrte.a5720.0510121.

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In this work, novel cooperative communication strategies like Decode and Forward based relay schemes, joint maximum likelihood signal detection in combinational Multiple Input Multiple Output (MIMO) cooperative relay cognitive networks are used. The joint cooperative signal detection using Maximum-Likelihood (ML) detector at each relays, and associated path links improves the quality of services at the destination node, which can be dynamically altered using different relay combinations and associated iterative computational complexity accumulated during ML detection. Here the relay performs ML decoding and transmit the detected symbols to the destination and also to the multiple antennas equipped for cooperative communication. The same ML detection at the destination combines the MIMO based diversity to narrow down the error probability among different orthogonal transmissions. The combination of iterative signal detection and relay assisted decoding scheme shows superior error rate performance when compared to non-iterative hard decoded signal detection. The simulations results proved the influence of MIMO assisted cooperative communication and the associated performance penalty gaps that come with imperfect channel state information at the destination node.

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Yang, Z. Q., Y. X. Li, J. B. Zhang, et al. "Effects of the red:far-red light ratio on photosynthetic characteristics of greenhouse cut Chrysanthemum – Short communication." Horticultural Science 40, No. 1 (2013): 40–43. http://dx.doi.org/10.17221/43/2012-hortsci.

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For the use of LED as a light source to regulate the photosynthesis of chrysanthemum leaves under greenhouse conditions, the effects of different red (660 &plusmn; 30 nm) to far-red (730 &plusmn; 30 nm) radiation ratios (R:FR) on the photosynthetic characteristics and chlorophyll fluorescence parameters of chrysanthemum leaves were studied. Red and far-red LED light sources were combined in different proportions to produce four R:FR ratio treatments: 0.5, 2.5, 4.5 and 6.5. The chlorophyll a content, SPAD value, net photosynthetic rate, light-saturated maximum photosynthetic rate, CO<sub>2</sub>-saturated carboxylation rate, apparent quantum efficiency and carboxylation efficiency were all the highest under the R:FR ratio of 2.5, followed by the R:FR ratio of 4.5. Potential photochemical efficiency of photosystem II, photochemical quenching and electron transport rate for the R:FR ratios of 2.5 and 4.5 were markedly higher than those for 0.5 and 6.5, however, those parameters did not differ significantly between the R:FR ratios of 2.5 and 4.5.

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Nagaraju, Samala, and Vidhyacharan Bhaskar. "Outage Probability of Maximal Ratio Combiner in the Presence of Adjacent Cell Interference and Adjacent Channel Interference." Wireless Personal Communications 90, no. 4 (2016): 1581–95. http://dx.doi.org/10.1007/s11277-016-3412-8.

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Ma, She Xiang, and Yuan Zhang. "Power Allocation for Multi-Relay Nodes Based on Signal-Noise-Ratio." Advanced Materials Research 403-408 (November 2011): 2255–58. http://dx.doi.org/10.4028/www.scientific.net/amr.403-408.2255.

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In wireless communication system, the cooperative diversity is a new space diversity mode. Power allocation plan aiming at maximizing the signal-noise-ratio (SNR) for multi-relay cooperative nodes system is discussed. Diversity signals are combined by the maximum ratio at the destination node. The research results show that 1) when the received noise level at destination node is very low, it can be neglected; 2) when the power allocation coefficients are proportional to the square of the channel gains from the source node to the relay nodes, the SNR of system is maximized in the maximum ratio combination model; and 3) When the received noise at destination node cannot be neglected, the power allocation coefficients are correlative to the received noise at destination node, the amplifying coefficients and the fading coefficients. The SNR of system can be enhanced by using the plan compared with traditional equal power allocation plan.

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Matuschek, C., E. Bölke, S. Gripp, W. Budach, D. Hermsen, and M. Peiper. "Mediator release during combined radio chemotherapy in rectal carcinoma." Journal of Clinical Oncology 27, no. 15_suppl (2009): 3043. http://dx.doi.org/10.1200/jco.2009.27.15_suppl.3043.

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3043 Background: Bacterial translocation is a well-documented phenomenon after polytrauma and major abdominal surgery. Today neoadjuvant chemoradiotherapy is the gold standard for uT3, N+ rectal cancer. The aim of this study was to evaluate if a gut barrier dysfunction occurred during radiotherapy and elective rectal surgery. Methods: We investigated in 45 patients (25 male, 20 female) with uT3N+ rectal carcinoma and neoadjuvante long-term radio chemotherapy with 5-FU and pelvis irridation up to 50.4 Gy on admission and weekly during radiotherapy and after surgery IL-6, LPS-binding protein, IL-8, TNF-α and procalcitonin. Results: There were no clinical complications in all patients. During radiochemotherapy we could not detect a significant increase of the acute phase response. IL-6 plasma levels showed maximal values 6 h after surgery (270 pg/ml) und CRP had its maximal values 48 h (185 mg/l). IL-8, TNF-α, LPS-BP, and procalcitonin were not elevated during an uncomplicated postoperative course. Conclusions: During an uncomplicated course of radio chemotherapy we could not detect elevated mediator releases. During surgery we could find a significant mediator liberation, which correlated with the amount of the operative trauma. No significant financial relationships to disclose.

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Ben, Guangli, Xifeng Zheng, Yongcheng Wang, Ning Zhang, and Xin Zhang. "A Local Search Maximum Likelihood Parameter Estimator of Chirp Signal." Applied Sciences 11, no. 2 (2021): 673. http://dx.doi.org/10.3390/app11020673.

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A local search Maximum Likelihood (ML) parameter estimator for mono-component chirp signal in low Signal-to-Noise Ratio (SNR) conditions is proposed in this paper. The approach combines a deep learning denoising method with a two-step parameter estimator. The denoiser utilizes residual learning assisted Denoising Convolutional Neural Network (DnCNN) to recover the structured signal component, which is used to denoise the original observations. Following the denoising step, we employ a coarse parameter estimator, which is based on the Time-Frequency (TF) distribution, to the denoised signal for approximate estimation of parameters. Then around the coarse results, we do a local search by using the ML technique to achieve fine estimation. Numerical results show that the proposed approach outperforms several methods in terms of parameter estimation accuracy and efficiency.

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Ghotkar, Rhushikesh, Ellen B. Stechel, Ivan Ermanoski, and Ryan J. Milcarek. "Hybrid Fuel Cell—Supercritical CO2 Brayton Cycle for CO2 Sequestration-Ready Combined Heat and Power." Energies 13, no. 19 (2020): 5043. http://dx.doi.org/10.3390/en13195043.

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The low prices and its relatively low carbon intensity of natural gas have encouraged the coal replacement with natural gas power generation. Such a replacement reduces greenhouse gases and other emissions. To address the significant energy penalty of carbon dioxide (CO2) sequestration in gas turbine systems, a novel high efficiency concept is proposed and analyzed, which integrates a flame-assisted fuel cell (FFC) with a supercritical CO2 (sCO2) Brayton cycle air separation. The air separation enables the exhaust from the system to be CO2 sequestration-ready. The FFC provides the heat required for the sCO2 cycle. Heat rejected from the sCO2 cycle provides the heat required for adsorption-desorption pumping to isolate oxygen via air separation. The maximum electrical efficiency of the FFC sCO2 turbine hybrid (FFCTH) without being CO2 sequestration-ready is 60%, with the maximum penalty being 0.68% at a fuel-rich equivalence ratio (Φ) of 2.8, where Φ is proportional to fuel-air ratio. This electrical efficiency is higher than the standard sCO2 cycle by 6.85%. The maximum power-to-heat ratio of the sequestration-ready FFCTH is 233 at a Φ = 2.8. Even after including the air separation penalty, the electrical efficiency is higher than in previous studies.

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NAKIBOĞLU, G., S. P. C. BELFROID, J. GOLLIARD, and A. HIRSCHBERG. "On the whistling of corrugated pipes: effect of pipe length and flow profile." Journal of Fluid Mechanics 672 (February 18, 2011): 78–108. http://dx.doi.org/10.1017/s0022112010005884.

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Whistling behaviour of two geometrically periodic systems, namely corrugated pipes and multiple side branch systems, is investigated both experimentally and numerically. Tests are performed on corrugated pipes with various lengths and cavity geometries. Experiments show that the peak-whistling Strouhal number, where the maximum amplitude in pressure fluctuations is registered, is independent of the pipe length. Experimentally, a decrease of the peak-whistling Strouhal number by a factor of two is observed with increasing confinement ratio, i.e. the ratio of pipe diameter to cavity width. A numerical methodology that combines incompressible flow simulations with vortex sound theory is proposed to estimate the acoustic source power in periodic systems. The methodology successfully predicts the Strouhal number ranges of acoustic energy production/absorption and the nonlinear saturation mechanism responsible for the stabilization of the limit cycle oscillation. The methodology predicts peak-whistling Strouhal numbers in agreement with experiments and explains the dependence of the peak-whistling Strouhal number on the confinement ratio. Combined with an energy balance, the proposed methodology is used to estimate the acoustic fluctuation amplitudes.

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He, Yong Hong, Hong Yan Wen, and Peng Wei Jin. "Application in Deformation Monitoring Signal Based on Wavelet Modular Maximum Algorithm." Advanced Materials Research 591-593 (November 2012): 1862–67. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.1862.

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In the deformation monitor data, the noise exists inevitably. According to the different dissemination characteristic of the signal and the noise in the different scale, Wavelet modular maximum de-nosing algorithm combines the method of threshold de-noising with scale trading theory by Witkin, and picks out modular maximum value of the noise, makes use of Modular Maximum value of the signal to recover the coefficients of different scale efficiently, until recovers the signal. Contrast to the traditional threshold value and translation invariance, the processing result shows de-nosing method based on wavelet modular maximum can pick out the noise in the deformation data, protect the original information, have a better effect on de-noising, enforce the signal to noise ratio,Wavelet modular maximum de-nosing algorithm is a effective method in the deformation monitor data processing.

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Su, Y.-F., and C.-K. Chen. "Application of exergy method to a two-stage irreversible combined refrigeration system." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 221, no. 7 (2007): 807–13. http://dx.doi.org/10.1243/0954406jmes459.

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The exergy method, based on the maximum exergetic efficiency criterion, is applied to a two-stage irreversible combined refrigeration system. The exergetic efficiency defined as the ratio of rate of exergy output to rate of exergy input is taken as the objective index to be maximized. The related cycle temperature parameters are first solved. The maximum exergetic efficiency is then obtained analytically. Comparisons between the exergetic efficiency and the coefficient of performance of the combined refrigeration system are performed. The influences of various parameters on the system performances are discussed. It shows that the exergy method is practical and effective when operating or designing the combined refrigeration system.

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Kitching, Ian D. "GPS and Cellular Radio Measurement Integration." Journal of Navigation 53, no. 3 (2000): 451–63. http://dx.doi.org/10.1017/s0373463300008936.

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In many combined GPS/cellular radio receivers, the cellular radio segment is not used to aid the positioning process. Recently proposed Assisted-GPS systems use the communications channel to improve receiver time-to-first-fix and the GPS tracking sensitivity. However, the cellular radio signals can also be used for locating the receiver. Studies using the GSM mobile communication system have shown positional accuracy comparable to that of SA-degraded GPS. To achieve maximum performance (accuracy, availability, integrity and reliability), both sources of positioning information, GPS and cellular, should be regarded as sensor inputs to an integrated navigation system. In this way the benefits of both systems can be fully exploited to produce an optimal navigation solution.

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Oskarsson, Johanna, and Kerry McGawley. "No individual or combined effects of caffeine and beetroot-juice supplementation during submaximal or maximal running." Applied Physiology, Nutrition, and Metabolism 43, no. 7 (2018): 697–703. http://dx.doi.org/10.1139/apnm-2017-0547.

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Dietary supplements such as caffeine and beetroot juice are used by athletes in an attempt to optimize performance and therefore gain an advantage in competition. The aim of this study was to investigate the individual and combined effects of caffeine and beetroot-juice supplementation during submaximal and maximal treadmill running. Seven males (maximal oxygen uptake: 59.0 ± 2.9 mL·kg–1·min–1) and 2 females (maximal oxygen uptake: 53.1 ± 11.4 mL·kg–1·min–1) performed a preliminary trial followed by 4 experimental test sessions. Each test session consisted of two 5-min submaximal running bouts (at ∼70% and 80% of maximal oxygen uptake) and a maximal 1-km time trial (TT) in a laboratory. Participants ingested 70 mL of concentrated beetroot juice containing either 7.3 mmol of nitrate (BR) or no nitrate (PBR) 2.5 h prior to each test session, then either caffeine (C) at 4.8 ± 0.4 (4.3–5.6) mg/kg of body mass or a caffeine placebo (PC) 45 min before each test session. The 4 test sessions (BR-C, BR-PC, PBR-C, and PBR-PC) were presented in a counterbalanced and double-blind manner. No significant differences were identified between the 4 interventions regarding relative oxygen uptake, running economy, respiratory exchange ratio, heart rate (HR), or rating of perceived exertion (RPE) at the 2 submaximal intensities (P > 0.05). Moreover, there were no significant differences in performance, maximum HR, peak blood lactate concentration, or RPE during the maximal TT when comparing the interventions (P > 0.05). In conclusion, no beneficial effects of supplementing with typical doses of caffeine, beetroot juice, or a combination of the two were observed for physiological, perceptual, or performance responses during submaximal or maximal treadmill running exercise.

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Spitas, V., and C. Spitas. "Optimizing involute gear design for maximum bending strength and equivalent pitting resistance." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 221, no. 4 (2007): 479–88. http://dx.doi.org/10.1243/0954406jmes342.

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Standard involute gear designs dominate high-power transmission applications because they combine sufficient bending strength with high pitting resistance, while retaining an adequate contact ratio. In this paper, a non-standard, optimal alternative involute gear design has been presented, which has the same pitting resistance as the standard involute gears but exhibits maximum resistance to bending. The optimization procedure is based on the complex algorithm, where the root stress, as calculated through tabulated boundary element analysis values, is the objective function and the active constraints include all of the kinematical, manufacturing and geometrical conditions, which must be satisfied by the optimal design, including the pitting resistance. The results indicate that optimal designs can achieve up to 8.5 per cent reduction of the fillet stress. Two-dimensional photoelasticity was used to verify the optimization results.

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Hwang, Beong Bok, G. M. Lee, Y. H. Lee, J. H. Ok, and S. H. Kim. "An Analysis on the Force Requirement of Combined Operations for Forward and Backward Tube Forming." Materials Science Forum 519-521 (July 2006): 943–48. http://dx.doi.org/10.4028/www.scientific.net/msf.519-521.943.

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In the present study, the finite element analysis has been conducted to investigate the deformation characteristics of forward and backward can extrusion process using AA 1100 aluminum alloy tubes in terms of maximum forming load and extruded length ratio in a combined material flow. A commercially available code is used to conduct rigid-plastic FEM simulation. Hollow tubes are selected as initial billets and the punch geometries follow the recommendation of ICFG. Selected design parametrs involved in simulation includes punch nose radius, die corner radius, frictional condition, and punch face angle. The investigation is foucused on the analysis of deformation pattern and its characteristics in a forward tube extrusion combined simultaneously with backward tube extrusion process main in terms of force requirements for this operation according to various punch nose radii and backward tube thickness. The simulation results are summarized in terms of load-stroke relationships for different process parameters such as backward tube thickness, die corner radii, and punch face angle, respectively, and pressure distributions exerted on die, and comparison of die pressure and forming load between combined extrusion and two stage extrusion process in sequencial operation. Extensive analyses are also made to investigate the relationships between process parameters and extruded lengths in both forward and backward directions. It has been concluded from simulation results that a) the combined operation is superior to multi-stage extrusion process in sequential operation in terms of maximum forming load and maximum pressure exerted on die, b) the length of forward extruded tube increases and that of backward extruded tube decreases as the thickness ratio decreases, and c) the forming load is influenced much by the thickness ratio and the other design factors such as die corner radius and punch face angle does not affect much on the force requirement for the combined extrusion process.

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Elgam, Avner, Yael Balal, and Yosef Pinhasi. "Study of 5G-NR-MIMO Links in the Presence of an Interferer." Electronics 10, no. 6 (2021): 732. http://dx.doi.org/10.3390/electronics10060732.

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Many communication systems are based on the Multiple Input, Multiple Output (MIMO) scheme, and Orthogonal Space–time Block Transmit diversity Coding (OSTBC), combined with Maximal Ratio Receive Combining (MRRC), to create an optimal diversity system. A system with optimal diversity fixes and optimizes the channel’s effects under multi-path and Rayleigh fading with maximum energy efficiency; however, the challenge does not end with dealing with the channel destruction of the multi-path impacts. Susceptibility to interference is a significant vulnerability in future wireless mobile networks. The 5th Generation New Radio (5G-NR) technologies bring hundreds of small cells and pieces of User Equipment (UE) per indoor or outdoor local area scenario under a specific Long Term Evolution (LTE)-based station (e-NodeB), or under 5G-NR base-station (g-NodeB). It is necessary to study issues that deal with many interference signals, and smart jammers from advanced communication equipment cause deterioration in the links between the UE, the small cells, and the NodeB. In this paper, we study and present the significant impact and performances of 2×2 Alamouti Phase-Shift Keying (PSK) modulation techniques in the presence of an interferer and a smart jammer. The destructive effects affecting the MIMO array and the advanced diversity technique without closed-loop MIMO are analyzed. The performance is evaluated in terms of Bit Error Rate (BER) vs. Signal to Interference Ratio (SIR). In addition, we proved the impairment of the orthogonal spectrum assumption mathematically.

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Penloup, Q., K. Roncin, and Y. Parlier. "Influence of Kite Characteristics on Propulsive Power Applied to Ship Auxiliary Propulsion." Journal of Sailing Technology 6, no. 01 (2021): 173–92. http://dx.doi.org/10.5957/jst/2021.6.1.173.

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A Design of Experiment method was applied combined with a performance prediction program to assess the influence of four design parameters on the propulsive capacity of kites used as auxiliary propulsion for merchant vessels. Those parameters are the lift coefficient, the lift to drag ratio or drag angle, the maximal load bearable by the kite and the ratio of the tether length on the square root of the kite area. These parameters are independent from the kite area and, therefore, they could be used with various kite ranges and types. The maximum wing load parameter is the one that shows the most influence on the propulsive force. Over 50% of the gains obtained through this study are directly attributable to it. Then the ratio of the tether length on the square root of the kite area comes as the second greatest influence factor for true wind angles above 70°. While the drag angle is more influential for the narrower angles. In fact, the most substantial gains are made upwind.

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Li, Guo Cheng, Ping Sun, and Peng Hu. "Numerical Simulation Study of the Influence of Structural Parameters of Combustion Chamber on In-Cylinder Flow Field of Diesel Engine." Advanced Materials Research 860-863 (December 2013): 1729–32. http://dx.doi.org/10.4028/www.scientific.net/amr.860-863.1729.

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Based on the entity model of the type 4B26 diesel engine, calculated by CFD FIRE and combined with the software BOOST for the initial boundary conditions, the influence of combustion chamber structural parameters, such as boss height, surface-volume ratio and diameter-depth ratio of combustion chamber, on in-cylinder flow field of diesel engine was investigated. The results show that the influence of the boss height on flow field in the cylinder and the transient swirl ratio is obvious, and increasing the boss height is beneficial to urge the formation of mixture rapidly. Reducing the surface-volume ratio is beneficial for improving the maximum transient swirl ratio, and the air strength maintains well also, but has little influence to the retentivity of the swirl intensity. Meanwhile, reducing the diameter-depth ratio does not only improves the air flow movement strengthen in the combustion chamber, but also enhances the maximum transient swirl ratio, and the retentivity of swirl flow movement is satisfying.

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Yang, Xi, Jinchao Yu, Feng Tian, et al. "The combined effect of heat-draw ratios and residence time on the morphology and property of aromatic copolysulfonamide fibers." RSC Advances 5, no. 34 (2015): 27163–67. http://dx.doi.org/10.1039/c5ra01868d.

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More perfect structure of the aromatic copolysulfonamide (co-PSA) fiber only could be formed with favourable draw ratio and residence time, which corresponds to the maximum strength of the heat-drawn fibers.

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Shi, Nan Nan, Da Hai Huang, and Run Xiao Zhang. "Effect of Reinforcement Size on Concrete Crack Width with the Same Reinforcement Ratio." Applied Mechanics and Materials 193-194 (August 2012): 600–604. http://dx.doi.org/10.4028/www.scientific.net/amm.193-194.600.

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The quantitative influence of tensile steel bars size on the concrete crack width is analyzed. According to the engineering experience, the smaller diameter steel bars are superior to the bigger ones with the same reinforcement ratio consideration. However, the quantitative analyses have not been well treated. The criterion of “element with the maximum tensile stress will crack” and classic formula of the crack width in “Design code for hydraulic concrete structures”, are combined to analyze the uniaxial tensile specimens. Finally, three conventional diameters of tensile steel bars (14, 16 and 20mm) are adopted to verify the finite element model (FEM), and the quantitative analyses can be employed to the engineering reinforcement design.

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Chen, Xi Liang, and Qing Nan Shi. "Research on Roll Welding Process of Cu/Al Composite Plates." Advanced Materials Research 743 (August 2013): 227–30. http://dx.doi.org/10.4028/www.scientific.net/amr.743.227.

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Cu/Al composites have the advantage of both copper and aluminum, i.e., the high electrical conductivity, high thermal conductivity, and low contact resistance of copper; the lightweight and corrosion resistant of aluminum. Roll welding is one common method to produce Cu/Al composite plates. The effects of rolling reduction ratio and annealing temperature on combined strength are analyzed by experiments. The results demonstrate that the combined strength increases with the increase of rolling reduction ratio, and at around 300°C the combined strength achieves the maximum value. The reason is then analyzed respectively. The results are helpful for understanding the Cu/Al combing mechanism, and are useful for improving the producing process of Cu/Al composite plates.

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