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PSO-DBNet for Peak-to-Average Power Ratio Reduction Using Deep Belief Network
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作者 A.Jameer Basha M.Ramya Devi +3 位作者 S.Lokesh P.Sivaranjani D.Mansoor Hussain Venkat Padhy 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1483-1493,共11页
Data transmission through a wireless network has faced various signal problems in the past decades.The orthogonal frequency division multiplexing(OFDM)technique is widely accepted in multiple data transfer patterns at... Data transmission through a wireless network has faced various signal problems in the past decades.The orthogonal frequency division multiplexing(OFDM)technique is widely accepted in multiple data transfer patterns at various frequency bands.A recent wireless communication network uses OFDM in longterm evolution(LTE)and 5G,among others.The main problem faced by 5G wireless OFDM is distortion of transmission signals in the network.This transmission loss is called peak-to-average power ratio(PAPR).This wireless signal distortion can be reduced using various techniques.This study uses machine learning-based algorithm to solve the problem of PAPR in 5G wireless communication.Partial transmit sequence(PTS)helps in the fast transfer of data in wireless LTE.PTS is merged with deep belief neural network(DBNet)for the efficient processing of signals in wireless 5G networks.Result indicates that the proposed system outperforms other existing techniques.Therefore,PAPR reduction in OFDM by DBNet is optimized with the help of an evolutionary algorithm called particle swarm optimization.Hence,the specified design supports in improving the proposed PAPR reduction architecture. 展开更多
关键词 5G wireless network orthogonal frequency division multiplexing signal distortion peak to average power ratio partial transmit sequence deep belief network
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Identified the hydrochemical and the sulfur cycle process in subsidence area of Pingyu mining area using multi-isotopes combined with hydrochemistry methods
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作者 Hui-Meng Su Fa-Wang Zhang +4 位作者 Jing-Yu Hu Jin-Feng Lei Wei Zuo Bo Yang Yu-Hua Liu 《Journal of Groundwater Science and Engineering》 2024年第1期62-77,共16页
Groundwater serves as an important water source for residents in and around mining areas.To achieve scientific planning and efficient utilization of water resources in mining areas,it is essential to figure out the ch... Groundwater serves as an important water source for residents in and around mining areas.To achieve scientific planning and efficient utilization of water resources in mining areas,it is essential to figure out the chemical formation process and the ground water sulfur cycle that transpire after the coal mining activities.Based on studies of hydrochemistry and D,^(18)O-H_(2)O,^(34)S-SO_(4)isotopes,this study applied principal component analysis,ion ratio and other methods in its attempts to reveal the hydrogeochemical action and sulfur cycle in the subsidence area of Pingyu mining area.The study discovered that,in the studied area,precipitation provides the major supply of groundwater and the main water chemistry effects are dominated by oxidation dissolution of sulfide minerals as well as the dissolution of carbonate and silicate rocks.The sulfate in groundwater primarily originates from oxidation and dissolution of sulfide minerals in coal-bearing strata and human activities.The mixed sulfate formed by the oxidation of sulfide minerals and by human activities continuously recharges the groundwater,promoting the dissolution of carbonate rock and silicate rock in the process. 展开更多
关键词 PCA Ion ratio Water chemistry Sulfide minerals Multi-isotopes Subsidence area of mining area
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The migration of the crustal deformation peak area in the eastern Himalayan Syntaxis inferred from present-day crustal deformation and morpho-tectonic markers
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作者 Ling Zhang Shiming Liang +1 位作者 Xiaoping Yang Chenglong Dai 《Geodesy and Geodynamics》 CSCD 2021年第3期165-174,共10页
The present-day Global Positioning System(GPS)velocity field shows that the Indian Plate is not a complete rigid block,as its northeastern corner has been torn off and clockwise rotating relative to the main part.With... The present-day Global Positioning System(GPS)velocity field shows that the Indian Plate is not a complete rigid block,as its northeastern corner has been torn off and clockwise rotating relative to the main part.With the updated GPS velocity data,the Euler vector of the northeastern corner of the Indian Plate relative to the stable main plate is deduced as(89.566±0.06°E,26.131±0.05°N,1.34±0.11°/Myr).The peak area of the present-day crustal deformation is located in the Chayu deformation belt with the compressional dilation strain rate over 160 nanostrain/yr.However,the Namche-Barwa Syntaxis with the massive crustal thickening and intense surface erosion is generally considered to be the previous locus of the strongest compressional stress in the Eastern Himalayan Syntaxis over long geological timescales.Thus,there is a discrepancy between the previous and present-day crustal deformation peak areas.We argue the migration of the crustal deformation peak area with a total distance of about 120 km and ascribe it to the variation of stress conditions caused by northeast India’s clockwise rotation. 展开更多
关键词 GPS velocity Eastern himalayan syntaxis LANDFORM Crustal deformation peak area
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The Attenuation Law of Horizontal Peak Acceleration on the Rock Site in Yunnan Area
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作者 Xiang Jianguang and Gao DongSeismological Bureau of Yunnan Province,Kunming 650041,China 《Earthquake Research in China》 1994年第4期112-119,共8页
In this paper,we select 131 accelerograms observed in the Yunnan area and cite 114 accelerograms from western America.By statistical regression analysis,we get two separate acceleration attenuation formulations based ... In this paper,we select 131 accelerograms observed in the Yunnan area and cite 114 accelerograms from western America.By statistical regression analysis,we get two separate acceleration attenuation formulations based on the data of Yunnan and those of both Yunnan and western America.By analyzing and comparing the above results with the result deprived from intensity-earthquake ground motion,this paper proposes the formula below,which may show the acceleration attenuation feature of the Yunnan area:Ap=1291.07e0.5275Ms(R+15)-t. 展开更多
关键词 The ATTENUATION of peak acceleration ROCK SITE YUNNAN area
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Evaluation of a traditional method for peak flow discharge estimation for floods in the Wenchuan Earthquake area,Sichuan Province,China 被引量:1
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作者 GUO Xiao-jun CUI Peng +3 位作者 LI Yong LIU Jin-feng GE Yong-gang WANG Ci-de 《Journal of Mountain Science》 SCIE CSCD 2019年第3期641-656,共16页
Peak discharge of flood in small mountainous watershed is usually calculated using the "Rainstorm–runoff calculation method in small watersheds in Sichuan Province"(RRM). This study evaluated the RRM calcul... Peak discharge of flood in small mountainous watershed is usually calculated using the "Rainstorm–runoff calculation method in small watersheds in Sichuan Province"(RRM). This study evaluated the RRM calculation using real-time monitored rainfall and hydrologic data from a small watershed in the Wenchuan Earthquake area of Sichuan Province, China. The results indicated that the discharge values given by the RRM are commonly overestimating the measured discharge. The overestimation rate was discussed and empirical equations were proposed for improving RRM estimations, based on the relationship between calculated and measured discharge values at different watershed scales(2, 30, and 40 km2), under different rainfall probabilities(0.97–0.5, 0.5–0.2, and 0.2–0.002), and for different rainfall durations(0–6, 6–24, and >24 h). The results of this study help contribute to the understanding of water floods formation and help provide more accurate estimations of peak flow discharge in small watersheds in the Wenchuan Earthquake area. 展开更多
关键词 RAINFALL RUNOFF yield INFLUX peak DISCHARGE WENCHUAN Earthquake area
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Application of Different Image Processing Techniques on Aster and ETM+ Images for Exploration of Hydrothermal Alteration Associated with Copper Mineralizations Mapping Kehdolan Area (Eastern Azarbaijan Province-Iran) 被引量:2
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作者 Golchin Hajibapir Mohammad Lotfi +1 位作者 Afshar Zia Zarifi Nima Nezafati 《Open Journal of Geology》 2014年第11期582-597,共16页
The Kehdolan area is located at 20 kilometers to the?south-east of Dozdozan Town (Eastern Azarbaijan Province). According to structural geology, volconic rocks are situated in Alborz-Azarbyjan zone, and faults?are?obs... The Kehdolan area is located at 20 kilometers to the?south-east of Dozdozan Town (Eastern Azarbaijan Province). According to structural geology, volconic rocks are situated in Alborz-Azarbyjan zone, and faults?are?observed?in?the?same direction to this system with SE-NW trend. The results show that kaolinite alteration trend with Argilic and propylitic veins?is the?same direction with SW-NE faults in this area. Therefore, these faults with these trends can be considered as the mineralization control for determination of the alterations. Different image processing techniques,?such as false color composite?(FCC), band ratios, color ratio composite?(CRC), principal component?analysis?(PCA), Crosta technique, supervised spectral angle mapping?(SAM), are used for?identification of the alteration zones associated with copper mineralization. In this project ASTER?data are process and spectral analysis to fit for recognizing intensity and kind of argillic, propylitic,?philic, and ETM+ data?which?are process and to fit for iron oxide and relation to metal mineralization of the area. For recognizing different alterations of the study area, some chemical and mineralogical analysis data from the samples showed that ASTER data and ETM+ data were?capable of hydrothermal alteration mapping with copper mineralization.?Copper mineralization in the region is in agreement with argillic alteration. SW-NE trending faults controlled the mineralization process. 展开更多
关键词 Kehdolan area False COLOR COMPOSITE Band ratios COLOR ratio COMPOSITE Principal Component Analysis Crosta Technique Supervised Spectral Angle MAPPING ASTER DATA ETM+ DATA Alteration
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MULTI-PEAK MATCH INTENSITY RATIO METHOD OF QUANTI-TATIVE X-RAY DIFFRACTION PHASE ANALYSIS 被引量:5
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作者 G. Chu, Y.F. Cong and H.J. YouResearch Center of Analysis and Test, Liaoning University of Petroleum & Chemical Technology, Fushun 113001, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2003年第6期489-494,共6页
A new method for quantitative phase analysis is proposed by using X-ray diffraction multi-peak match intensity ratio. This method can obtain the multi-peak match intensity ratio among each phase in the mixture sample ... A new method for quantitative phase analysis is proposed by using X-ray diffraction multi-peak match intensity ratio. This method can obtain the multi-peak match intensity ratio among each phase in the mixture sample by using all diffraction peak data in the mixture sample X-ray diffraction spectrum and combining the relative intensity distribution data of each phase standard peak in JCPDS card to carry on the least square method regression analysis. It is benefit to improve the precision of quantitative phase analysis that the given single line ratio which is usually adopted is taken the place of the multi-peak match intensity ratio and is used in X-ray diffraction quantitative phase analysis of the mixture sample. By analyzing four-group mixture sample, adopting multi-peak match intensity ratio and X-ray diffraction quantitative phase analysis principle of combining the adiabatic and matrix flushing method, it is tested that the experimental results are identical with theory. 展开更多
关键词 X-ray diffraction multi-peak match intensity ratio quantitative phase analysis
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A Novel Peak-to-Average Power Ratio Reduction Scheme via Tone Reservation in OFDM Systems 被引量:1
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作者 Jurong Bai Yong Li +2 位作者 Wei Cheng Huimin Du Yanben Wang 《China Communications》 SCIE CSCD 2017年第11期279-290,共12页
In this paper, a novel signal-to-clipping noise ratio and least squares approximation tone reservation scheme(SCR-LSA TR) is proposed to reduce the peak-to-average power ratio for orthogonal frequency division multipl... In this paper, a novel signal-to-clipping noise ratio and least squares approximation tone reservation scheme(SCR-LSA TR) is proposed to reduce the peak-to-average power ratio for orthogonal frequency division multiplexing systems. During the SCR procedure, only the element with the maximal amplitude is picked for processing, which not only decreases the algorithm complexity, but also helps to overcome the BER deterioration. With the LSA method, the amplitude of the peak-cancelling signals can approximate to that of the original clipping noise as much as possible. Through the combination of the optimization factor in the LSA method, the classic SCR method can achieve better PAPR reduction with faster convergence. Simulation results show that the proposed SCR-LSA TR scheme has less in-band distortion and smaller out-of-band spectral radiation. The BER of the proposed scheme shows a better performance especially under the 16-QAM over the additive white Gaussian noise channel. 展开更多
关键词 orthogonal frequency division multiplexing peak-to-average power ratio tone reservation signal to clipping noise ratio
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Analysis of Similarities of Different Species of Boenninghausenia Plants by Common and Variant Peak Ratios Dual Indicator Sequence Method
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作者 Nannan LONG Risha WEIZE +3 位作者 Hairong ZHONG Xiaoxia CAI Yuan LIU Ying LI 《Medicinal Plant》 CAS 2019年第2期73-78,84,共7页
[Objectives] To analyze the similarities of Boenninghausenia sessilicarpa Levl. and Boenninghausenia albiflora(Hook.) Meiss by the common and variant peak ratio dual indicator sequence method. [Methods] Four different... [Objectives] To analyze the similarities of Boenninghausenia sessilicarpa Levl. and Boenninghausenia albiflora(Hook.) Meiss by the common and variant peak ratio dual indicator sequence method. [Methods] Four different solvents(petroleum ether, chloroform, ethyl acetate and methanol) were used to extract the chemical components of different polar regions of B. sessilicarpa and B. albiflora. UV-visible spectrophotometry(second derivative method) was used to collect the fingerprints of different solvent extracts, and common and variant peak peak ratios were analyzed for the absorption peak data. [Results] The common peak ratio and variant peak ratio data of ground parts of B. albiflora and B. sessilicarpa was S2∶S5(46.2(54.2, 62.5)), compared with the data of other groups, the common peak ratio was the largest, thus the components of ground parts of B. albiflora and B. sessilicarpa were closest and had the largest similarities; the common peak ratio and variant peak ratio data of the components extracted by chloroform from B. albiflora and B. sessilicarpa was Y2∶Y6(54.2(38.5, 46.2)), compared with the data of other groups, the variant peak ratio was the smallest, thus, the chemical components near the chloroform polarity of two kinds of medicinal materials had the largest similarities and smallest differences. [Conclusions] This method is simple and easy to operate, and the ultraviolet fingerprint data of four different polar organic solvent extracts are used for comprehensive analysis, and the results have high specificity and high accuracy. Besides, there are certain similarities and also differences between the chemical components of B. sessilicarpa and B. albiflora. It is expected to provide a new evaluation method for the variety quality of B. sessilicarpa and B. albiflora. 展开更多
关键词 Boenninghausenia albiflora (Hook.) Meiss Boenninghausenia sessilicarpa Levl. Ultraviolet fingerprint COMMON peak ratio VARIANT peak ratio
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Coral Ba/Ca and Mn/Ca Ratios as Proxies of Precipitation and Terrestrial Input at the Eastern Offshore Area of Hainan Island
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作者 JIANG Qiaowen CAO Zhimin +3 位作者 WANG Daoru LI Yuanchao WU Zhongjie NI Jianyu 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第6期1072-1080,共9页
Geochemical ratios in coral reef skeletons could be used as proxies to reconstruct past climatological and environmental records in data-poor regions. Using a 103-year data set(1902 to 2005), the annual variations in ... Geochemical ratios in coral reef skeletons could be used as proxies to reconstruct past climatological and environmental records in data-poor regions. Using a 103-year data set(1902 to 2005), the annual variations in Ba/Ca and Mn/Ca ratios of Porites lutea skeletons at an eastern offshore area of Hainan Island(19?12'28.4''N, 110?37'38.8''E) were analyzed using inductively coupled plasma-optic emission spectrometry(ICP-OES). The analysis results showed that Ba/Ca ratios varied from a minimum of 3.120 μmol mol^(-1) in 1903 to a maximum of 10.064 μmol mol^(-1) in 1944, with an average of 5.256 μmol mol^(-1). Mn/Ca ratios varied from 0.206 to 5.708 μmol mol^(-1) with an annual average of 1.234 μmol mol^(-1), with peak values in 2001, 1964 and 1932, that correlated with strong rainfall events caused by typhoons. Variation in Ba/Ca and Mn/Ca ratios were compared with available river discharge and precipitation records, providing insight into past climatological events. Human activities and their indirect effects could impact the strength of the relationship between Ba/Ca and Mn/Ca ratios and observed precipitation and terrestrial input in the future. 展开更多
关键词 PORITES lutea eastern offshore area of Hainan Island Ba/Ca and Mn/Ca ratios terrigenous INPUT PRECIPITATION climate proxy records
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Effect of Flood Peak Discharge Control by a Small Reservoir in an Urbanized Area—Case Study in the Kurabe River Basin, Japan
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作者 Kouzo Ito Manabu Segawa +1 位作者 Hiroshi Takimoto Toshisuke Maruyama 《Open Journal of Modern Hydrology》 2017年第4期314-330,共17页
Recently severe damage of flooding by urbanization was frequently occurred. To prevent this damage, small reservoir was constructed in the urbanized residential area. This paper describes an effect of flood peak disch... Recently severe damage of flooding by urbanization was frequently occurred. To prevent this damage, small reservoir was constructed in the urbanized residential area. This paper describes an effect of flood peak discharge control by a small reservoir (control reservoir) caused by rapidly developed urbanization. Although work for this purpose was conducted, research on the effects of the control reservoir was not conducted until now. This research, conducted by simulation, was a case study in the Kurabe River Basin in the Tedori River Alluvial Fan Area, Japan, based on the precise investigation of the reservoir in the actual field. The study was conducted to determine not only the actual control reservoir capacity for the newly developed residential area but also the ideal capacity for all present residential areas and the largest capacity allowable for a maximum rainfall event that recently occurred. The control reservoir effects between individual blocks and the entire basin area were compared by dividing the test basin into 15 blocks (sub-basins). The results showed that the effects on the capacity per unit area of the residential area in blocks have close relationship with the decreasing ratio of peak discharge in blocks. Consequently, the effects of control reservoir capacity and the limitation were clarified. In the future, control reservoirs should be constructed for all of the already developed residential areas, for example, by utilizing underground car parking lot. The results of this research can contribute to the design of the control reservoir for protection against flooding damage in urbanized areas. 展开更多
关键词 FLOOD Control RESERVOIR DISCHARGE from Urbanized area Unit FLOOD DISCHARGE peak DISCHARGE DECREASING ratio Simulation of Drainage DISCHARGE
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A new strategy for ionospheric remote sensing using the 130.4/135.6 nm airglow intensity ratios 被引量:2
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作者 XiaoHan Yin JianQi Qin Larry J.Paxton 《Earth and Planetary Physics》 CAS CSCD 2023年第4期445-459,共15页
We demonstrate here that global-scale determination of a key ionospheric parameter,the peak height of the F_(2)region(h_(m)F_(2)),can be obtained by making a simple ratio measurement of the atomic oxygen 130.4 and 135... We demonstrate here that global-scale determination of a key ionospheric parameter,the peak height of the F_(2)region(h_(m)F_(2)),can be obtained by making a simple ratio measurement of the atomic oxygen 130.4 and 135.6 nm emissions in the far-ultraviolet nightglow with a nadir-viewing system such as a pair of photometers suitable for flight on a CubeSat.We further demonstrate that measurements from an altitude that is within the typical range of nighttime h_(m)F_(2)250−450 km can provide the ratios that are needed for retrieval of the h_(m)F_(2).Our study is conducted mostly through numerical simulations by using radiative transfer models of the two emissions coupled with empirical models of the atmosphere and ionosphere.Modeling results show that the relationship between the h_(m)F_(2)and the intensity ratio is sensitive to the altitude from which the emissions are observed,primarily because of the distinctly different degrees of resonant scattering of the two emissions in the atmosphere.A roughly quadratic relationship can be established for observations from an orbit of~400 km,which enables h_(m)F_(2)retrieval.Parametric analysis indicates that the relationship can be affected by the ambient atmospheric conditions through resonant scattering and O2 absorption.For typical nighttime conditions with h_(m)F_(2)250−450 km,retrieval of the h_(m)F_(2)from synthetic observations shows that the typical errors are only a few kilometers(up to~20 km),depending on the accuracy of the ambient conditions predicted by the empirical models.Our findings pave the way for use of the 130.4/135.6 nm intensity ratios for global-scale monitoring of the nighttime ionosphere at mid to low latitudes. 展开更多
关键词 nighttime ionosphere far-ultraviolet remote sensing 130.4/135.6 nm airglow intensity ratio peak height of the F_(2)region(h_(m)F_(2)) TIMED observation
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Reducing Peak-to-Average Power Ratio of a Turbo Coded OFDM
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作者 Spyridon K. Chronopoulos Vasilis Christofilakis +1 位作者 Giorgos Tatsis Panos Kostarakis 《Wireless Engineering and Technology》 2012年第4期195-202,共8页
Peak to Average Power Ratio (PAPR) is defined as the instantaneous power (maximum value) to the average power ratio. PAPR is considered to be a major problem in OFDM systems. This problem can cause radical unexpected ... Peak to Average Power Ratio (PAPR) is defined as the instantaneous power (maximum value) to the average power ratio. PAPR is considered to be a major problem in OFDM systems. This problem can cause radical unexpected behavior of the signal fluctuation. This fluctuation is constituted by a large number of power states. The enormous number of these states leads to an additional complexity of ADCs and DACs. This research addresses the previous problem in OFDM systems utilizing Turbo Codes. μLaCP technique is employed for the purpose of decreasing PAPR. Moreover, our OFDM system was simulated in the presence of an AWGN channel with four types of codes (without the presence of ADCs and DACs). These were constituted of PCCC (typical and new), SCCC, and Convolutional Codes. Our Turbo Coded OFDM exhibited unchanged BER performance before and after the use of μLaCP technique. This was accomplished by modifying our previous PAPR reduction technique without sacrificing greatly its attributes. 展开更多
关键词 Orthogonal Frequency Division Multiplexing peak to Average Power ratio μ-Law μLaCP μLaIF Parallel CONCATENATED Convolutional Codes A POSTERIORI Probability Cyclic PREFIX Zero PADDING peak ratio Bit Error Rate
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Correlation between Surface Area Ratio of Medial to Lateral Tibial Plateau and Knee Alignment in Adults
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作者 Song GONG Li-zhi HAN +3 位作者 Tian-lun GONG Yi-hu YI Ruo-yu WANG Wei-hua XU 《Current Medical Science》 SCIE CAS 2022年第3期577-583,共7页
Objective This study aimed to investigate the correlation between the surface area ratio of medial tibial plateau(MTP)to lateral tibial plateau(LTP)and the mechanical tibiofemoral angle(mTFA).Methods Lower limb comput... Objective This study aimed to investigate the correlation between the surface area ratio of medial tibial plateau(MTP)to lateral tibial plateau(LTP)and the mechanical tibiofemoral angle(mTFA).Methods Lower limb computed tomography(CT)images were collected at our hospital.Then,the original CT data were analyzed and reconstructed using medical image processing software.The proximal and distal centres of the femur and tibia were marked.The surface areas of MTP and LTP were identified using image processing software.GraphPad Prism 8.0.2 was used to perform the statistical analysis.Results The surface area ratio of MTP to LTP was significantly correlated with the mTFA in all patients(P<0.0001),male group(P<0.0001),female group(P<0.0001),varus group(P<0.0001),and valgus group(P=0.002).Furthermore,the surface area of MTP and LTP was significantly greater in the male group than in the female group(P<0.0001).There was significant difference in the surface area of the MTP between the varus and valgus groups(P<0.0001).Significant difference was also observed in the surface area ratio of MTP to LTP between the varus and valgus groups(P<0.0001).Conclusion The surface area ratio of MTP to LTP was correlated with the mTFA.Within a certain range,the smaller the mTFA,the greater the surface area ratio of MTP to LTP.For patients undergoing total knee arthroplasty,of whom the surface area of the MTP was basically equal to that of the LTP,it is recommended that the osteotomy should be performed in accordance with mechanical alignment standards,and that a symmetrical tibial plateau prosthesis should be used.For patients whose surface area of MTP is significantly greater than that of the LTP,it is recommended that the osteotomy should be performed in accordance with kinematic alignment standards,and that an anatomical tibial plateau prosthesis should be used. 展开更多
关键词 knee alignment medial tibial plateau lateral tibial plateau surface area ratio prosthesis types total knee arthroplasty
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Phase-Space Areas of the Body Motion in the Solar System Deduced from the Bohr-Sommerfeld Atomic Theory and Approximate Invariance of Their Ratios for the Pairs of Planets and Satellites
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作者 Stanislaw Olszewski Tadeusz Kwiatkowski 《Journal of Modern Physics》 2012年第9期1142-1151,共10页
Energy-time and momentum-position phase spaces defined by the electron orbits in the hydrogen-like atom exhibit special properties of equivalence. It is demonstrated that equivalence of the same kind can be obtained f... Energy-time and momentum-position phase spaces defined by the electron orbits in the hydrogen-like atom exhibit special properties of equivalence. It is demonstrated that equivalence of the same kind can be obtained for the phase-space areas defined by the orbit pairs of planets, or satellites, which compose the solar system. In the choice of the examined areas it is useful to be guided by the Bohr-Sommerfeld atomic theory. 展开更多
关键词 ratios of the PHASE-SPACE areas and THEIR INVARIANCE Planets and SATELLITES Bohr-Sommerfeld Atomic Theory
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A PHASE SCRAMBLING SCHEME FOR SUPPRESSION OF PEAK TO AVERAGE POWER RATIO FOR OFDM
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作者 LiuYang ShiYin 《Journal of Electronics(China)》 2005年第1期66-69,共4页
The complex-valued modulating vectors for the subcarriers consist of two kinds of components: One is the information-bearing components superposed with pseudo-randomized phases and the other is the suppression compone... The complex-valued modulating vectors for the subcarriers consist of two kinds of components: One is the information-bearing components superposed with pseudo-randomized phases and the other is the suppression components with specified scrambling phases. The pseudo randomized phases are generated according to the predefined polynomial and mapping function whereas the scrambling phases are from a gradient algorithm. The simulation results verify the rationality and validity of the phase scrambling. 展开更多
关键词 Orthogonal Frequency Division Multiplexing (OFDM) peak to Average Power ratio (PAPR) Phase scrambling scheme
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A Study of the Correlation between the Concentration of Particulate Matter and Green Area Ratio Measured through a Portable Monitoring System: With Particular Focus on the Case of Dalseo-Gu, Daegu Metropolitan City
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作者 Kyungsu Son Sanghun Baek +1 位作者 Eungho Jung Daewuk Kim 《Journal of Environmental Protection》 2022年第1期84-96,共13页
This study analyzed the relationship between the measured concentration of particulate matter (PM) and green area, which is an important spatial factor affecting urban PM concentration and even more carbon neutral in ... This study analyzed the relationship between the measured concentration of particulate matter (PM) and green area, which is an important spatial factor affecting urban PM concentration and even more carbon neutral in cities. In order to investigate the effects of green area, the green area ratio (GAR) is used and correlated with particulate matter. As a result of analyzing the correlation between GAR and PM concentration using the measured PM data, it was found that there was a positive correlation between the two variables. Hence, the higher the GAR, the lower the PM concentration. It can be said that the introduction of spatial elements with high GAR scores, such as parks and forests in cities, is effective in reducing PM concentration. In this study, a portable PM monitoring system using a vehicle for PM measurement was also established and operated. As a result, it was found that a PM monitoring system using a light-scattering sensor is an effective PM measurement method that can be used at the local government level. It was also found that a follow-up study is needed in the future to identify the PM mitigation functions of urban green areas according to the detailed characteristics of green areas as well as various environmental factors. This study can be used in air quality improvement activities and efforts as reference data by policy decision makers and in the field of environmental planning associated with the removal of airborne particulate matter pollution in urban areas. 展开更多
关键词 Particulate Matter (PM) CORRELATION Green area ratio (GAR) Monitoring System
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A correlation OPTS algorithm for reducing peak to average power ratio of FBMC-OQAM systems
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作者 WANG Xing MA Tianming +1 位作者 LI Fengrong ZHAO Qinghua 《High Technology Letters》 EI CAS 2022年第2期208-216,共9页
A correlation overlapping partial transmit sequence(C-OPTS) algorithm is proposed to solve the issue of high complexity of overlapping partial transmit sequence(OPTS) algorithm in suppressing the peak to average power... A correlation overlapping partial transmit sequence(C-OPTS) algorithm is proposed to solve the issue of high complexity of overlapping partial transmit sequence(OPTS) algorithm in suppressing the peak to average power ratio(PAPR) of filter bank multicarrier-offset quadrature amplitude modulation(FBMC-OQAM) signals.The V subblocks in partial transmit sequence(PTS) are regrouped into U combinations according to the correlation coefficient p,and overlapping subblocks are allowed between adjacent groups.The search starts from the first group and sets the phase factors of the subsequent groups to 1.When the phase factors of the non-overlapping subblocks in the first group are determined,the subsequent groups are searched in turn to determine their respective phase factors.Starting from the second data block,the data overlapped with it should be taken into account when determining its optimal phase factor vector.Theoretical analysis and simulation results indicate that compared with the OPTS algorithm,the proposed algorithm can significantly reduce the computational complexity at the cost of slight deterioration of PAPR performance.Meanwhile,compared with the even-odd iterative double-layers OPTS(ID-OPTS) algorithm,it can further reduce the complexity and obtain a better PAPR suppression effect. 展开更多
关键词 filter bank multicarrier(FBMC) offset quadrature amplitude modulation(OQAM) peak to average power ratio(PAPR) overlapping partial transmit sequence(OPTS) correlation coefficient
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Joint Optimization of Peak-to-Average Power Ratio and Spectral Leakage in 5G Multicarrier Waveforms
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作者 WEI Peng DAN Lilin +3 位作者 ZHOU Cheng XIAO Yue WU Gang LI Shaoqian 《China Communications》 SCIE CSCD 2015年第S1期83-92,共10页
High peak-to-average-power ratio(PAPR) and spectral leakage are two main drawbacks of multicarrier systems, such as in orthogonal frequency division multiplexing(OFDM), in future 5G wireless communications. For genera... High peak-to-average-power ratio(PAPR) and spectral leakage are two main drawbacks of multicarrier systems, such as in orthogonal frequency division multiplexing(OFDM), in future 5G wireless communications. For generating optimized wave forms for 5G communications, this paper proposes an iterative scheme combining time-domain N-continuous OFDM(TD-NC-OFDM) and serial peak cancellation(SPC). Based on the theory of projection onto convex sets(POCS), the effectiveness of the proposed scheme is proved, and the optimized time-frequency domain multicarrier waveforms are analyzed in terms of a balanced tradeoff between out-of-band spectral leakage and PAPR. Both theoretical analysis and simulation results show that the proposed scheme can jointly optimize both the PAPR and out-ofband radiation, with moderate computational complexity. 展开更多
关键词 orthogonal frequency division multiplexing(OFDM) peak-to-average-power ratio(PAPR) SPECTRAL LEAKAGE
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Simulation on Peak-to-Average Power Ratio for Orthogonal Frequency Division Multiplexing
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作者 SHAN Weifeng MENG Baohong LIU Ningning LI Hui ZHANG Hongwei 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1873-1876,共4页
Clipping is a simple and convenient PAPR (peak-to-average power ratio) reduction method for high speed OFDM (orthogonal frequency division multiplexing) communication system. In this paper, we propose a new PAPR r... Clipping is a simple and convenient PAPR (peak-to-average power ratio) reduction method for high speed OFDM (orthogonal frequency division multiplexing) communication system. In this paper, we propose a new PAPR reduction method for Wireless-MAN(metropolitan area network)-OFDM system based on IEEE 802.16, which is over-sampling clipping arithmetic. Simulation and performance of the over-samples clipping's PAPR reduction capability, BER effect is given. The simulation indicates that the PAPR of at least 99.9% OFDM symbol is below 6dB after 2 Nyquist rate clipping, and the performance of BER has 1dB SNR(signal noise ratio) loss. The results prove that this method has better capacity to reducing PAPR. So it can be well used in WMAN-OFDM system. 展开更多
关键词 peak-to-average power ratio OFDM(orthogonal frequency divisior multiplexing) CLIPPING
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