Dynamic spectrum allocation for cognitive radio sensor networks based on improved genetic algorithm by Chang CAI, Yafang WANG, Bingmei MIAO, Hui JIANG

“…ISM (industrial scientific and medical) bands where wireless sensor network works faced with the shortage of spectrum resources problems.Aimed at this case,dynamic spectrum allocation in cognitive radio technology was applied in wireless sensor network.A dynamic frequency spectrum allocation scheme was proposed.The algorithm was a modified adaptive genetic algorithm which was based on graph coloring model.In addition,the objective functions of the algorithm were maximum bandwidth gains and minimum spectrum handoff,besides,in the crossover and mutation process,adaptive crossover probability and mutation probability was used instead of the fixed.Experimental results confirm that compared with the traditional genetic algorithm and color sensitive graph coloring algorithm,the proposed algorithm can achieve the expected goal of improving the spectral efficiency and reducing energy consumption.…”
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Quantum yields of photocoloration and molar absorption coefficients of ferrocenyl substituted benzo and dibenzochromenes. Comparison with their phenyl-homologues by Pierre Brun, Robert Guglielmetti, Jean Claude Micheau, Véronique Pimienta, Stéphane Anguille

“…It was shown that the ferrocenyl- substitution induces the formation of a new band in the 500–700 nm range in the open forms, however, it does not affect significantly the UV spectra of the closed forms. …”
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Some Recent Developments in Adaptive Tuned Vibration Absorbers/Neutralisers by Michael J. Brennan

“…A limitation of the device, however, is that it acts like a notch filter, only being effective over a narrow band of frequencies. Recent developments have overcome this limitation by making it possible to tune the device over a range of frequencies. …”
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Substrate Integrated Slot Array Antenna with Required Radiation Pattern Envelope by M. M. Zhou, Y. J. Cheng, W. N. Huang

“…After that, the geometrical dimension of the substrate integrated slot array can be synthesized. As an example, a K-band 16 × 22 slot array antenna based on the substrate integrated waveguide (SIW) technology is designed, fabricated, and measured. …”
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Experimental Study on Deep Carburizing Process and Distortion Control of Large Modulus Rack by Li Baokui, Lu Jinsheng

“…The results show that, by the multi-stage carburizing process with high intensity carburizing and diffusion, the depth of the carburizing layer of the rack is up to 0.5 mm,the bending deformation of rack is 0.8~1.4 mm by process equipment and process control, and the metallographic structure are effectively controlled.…”
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Empirical research on the diffusion effect of ICT innovation diffusion and prediction in China by Wenyu HU, Wenju WANG

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A Low-Profile and Compact Split-Ring Antenna with Horizontally Polarized Omnidirectional Radiation by Kittima Lertsakwimarn, Chuwong Phongcharoenpanich, Takeshi Fukusako

“…The −10-dB S11 of the antenna covers the 920-MHz RFID band, and the gain is about 1.45 dBi in the parallel direction to the ground plane. …”
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Statistical Analysis of Radio Propagation Channel in Ruins Environment by Jiao He, Er-Ping Li, Sai-Qiong Zhou, Kun Liao

“…The radio propagations at three typical mobile communication bands (0.9, 1.8, and 2 GHz) are investigated in two different scenarios. …”
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RESEARCH ON CALCULATION METHOD OF AXIAL COMPRESSION LOAD-CARRYING CAPACITY OF INTEGRALLY STIFFENED PANEL by LIU Cun, WAN YaFeng, LI Jian

“…This paper proposes the equivalent calculating method based on the bending resistance of stiffened panels,axial compression tests of stiffened panels have verified the accuracy of the calculation method for the three types skin effective width,influences of shot peening on compressive strength of wing stiffened panel are considered by comparison on crippling test results of shot peened and unpeened panel element,afterwards,a more perfect and accurate,practical engineering calculation method is established.…”
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鸟类环志的简介 by 许维枢

“…<正> （一）环志的意义鸟类环志（Bird-Banding）是获得有关鸟类迁徙资料的一种科学方法。通过环志可以了解和研究鸟类迁徙、散布、季节运动、归巢能力、死亡率、存活率、寿命、种群大小、种群结构、配育经久性、地点和场所、日活动,以及有关生境、行为等方面的基本数据。…”
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Development of a Zero-Bias Detector Based on T-Type Structure by Xiaobo Zhang, Jin Meng, Jingtao Zhou, Baijun Zhang, Zenghui Liu, Zexing Yuan

“…This paper provides a detailed introduction to the design concept, working principle, and experimental results of the detector, which lays the device foundation for the development of terahertz focal plane imaging systems and provides support for future terahertz applications in higher frequency bands.…”
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Comparing Two Observational Systems in the Assessment of Knee Pain by Shannon Fuchs-Lacelle, Thomas Hadjistavropoulos, Donald Sharpe, Jaime Williams, Ronald Martin, Diane LaChapelle

“…It was expected that the more discomforting physiotherapy activities (knee bending and quadriceps exercises) would result in more pain behaviours than intermediate activities (walking and standing), which, in turn, would result in more pain behaviours than reclining. …”
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Design and Analysis of the Elastic Torsion Shafting in Split Torque Transmission System of Cylindrical Gear by Pan Lei, Zhu Rupeng, Jin Guanghu, Ren Wei

“…According to the design pattern,two analysis models of elastic torsion shafting and split torque transmission system with elastic torsion shafting are established with Romax.A study on characteristic of force transmission and load sharing of elastic torsion shafting is carried out.The modal analysis is also carried out for split torque transmission system with elastic torsion shafting.The study results show that the main flexible shaft is subjected to torque but not influenced by bending moment.The elastic torsion shafting has better characteristic of load sharing than common duplicate gear shaft.The running condition of system with elastic torsion shafting is out of resonance region.The study results are a theoretical guide for engineering design and dynamic analysis of this split-torque transmission system.…”
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Joint source-channel coding for image transmission based on best wavelet packet by Jun-hong CHEN, Qin-yu ZHANG

“…A novel joint source/channel image coding algorithm was proposed based on the best wavelet packet in a rate-distortion sense.Different from other wavelet packet image coding,the channel and the channel code information were introduced to the source coding,so the proposed algorithm was a joint source-channel coding.The coding of wavelet packet sub-band was bit plane,accorolingly,the bit streams could be good match to UEP.And a WICP-LDPC code was using as a channel code.The simulation results in BSC channel show that,the proposed algorithm is better than the EEP image transmission system.And the proposed algorithm is also better than several other image transmission algorithms,which proposed recently.…”
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A Compact RFID Reader Antenna for UHF Near-Field and Far-Field Operations by Lai Xiao zheng, Xie Zeming, Cen Xuanliang

“…This antenna, printed on a 0.8 mm thick FR4 substrate with a small size of 31 mm × 31 mm, achieves good impedance bandwidth from 897 to 928 MHz, which covers USA RFID Band (902–928 MHz). The proposed loop configuration, with a split-ring resonator (SRR) coupled inside it, demonstrates strong and uniform magnetic field distribution in the near-field antenna region. …”
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Modern materials and technologies in the production of artificial casting by S. S. Tkachenko, V. O. Yemelyanov, K. V. Martynov

“…The strength of forms on an aqueous binder before calcination (bending strength σi) is from 1.5 to 2 MPa. The presented technology allows flexible coverage of the entire range of art products. …”
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Multi-Structure-Based Refractive Index Sensor and Its Application in Temperature Sensing by Zhaokun Yan, Shubin Yan, Ziheng Xu, Changxing Chen, Yuhao Cao, Xiaoran Yan, Chong Wang, Taiquan Wu

“…The simulation results show that the sharp asymmetric resonance generated by the interaction between the discrete narrow-band mode and the continuous wideband mode is called Fano resonance. …”
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Rest-to-Rest Attitude Naneuvers and Residual Vibration Reduction of a Finite Element Model of Flexible Satellite by Using Input Shaper by Setyamartana Parman, Hideo Koguchi

“…The finite element method is used to examine discrete elastic deformations of a particular model of satellite carrying flexible solar panels by modelling the panels as flat plate structures in bending. Results indicate that, under an unshaped input, the maneuvers induce undesirable attitude angle motions of the satellite as well as vibration of the solar panels. …”
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Low-complexity despreading scheme with repetition code for wireless body area networks by Yu CHI, Lan CHEN, Chao LV

“…To improve the reliability of data transmission and reduce the complexity of the narrow band receiver for wireless body area networks(WBAN),spreading with repetition code is used in IEEE 802.15.6 standard.A despreading structure in which the metrics of reliability were calculated selectively according to the dynamic threshold was designed.Combined with hard decision,hard threshold-combine and hard threshold-delete despreading methods by simplifying maximal ratio combining and generalized minimum distance principle respectively were proposed,which had low complexity and near-optimal performance.The theoretical analysis and simulation results show that compared to despreading based on maximum likelihood method,the spreading gain of the proposed methods is close to the theoretical value and the computational complexity can be reduced by 86% at most under high SNR circumstances.…”
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Estimation of fretting fatigue life using a multiaxial stress-based critical distance methodology by F. C. Castro, J. A. Araújo, M. S. T. Pires, L. Susmel

“…Most of the life estimates were within an error band given by a factor of 2.…”
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