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Recursive Filtering for Stochastic Systems With Filter-and-Forward Successive Relays
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作者 Hailong Tan Bo Shen +1 位作者 Qi Li Hongjian Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第5期1202-1212,共11页
In this paper,the recursive filtering problem is considered for stochastic systems over filter-and-forward successive relay(FFSR)networks.An FFSR is located between the sensor and the remote filter to forward the meas... In this paper,the recursive filtering problem is considered for stochastic systems over filter-and-forward successive relay(FFSR)networks.An FFSR is located between the sensor and the remote filter to forward the measurement.In the successive relay,two cooperative relay nodes are adopted to forward the signals alternatively,thereby existing switching characteristics and inter-relay interferences(IRI).Since the filter-and-forward scheme is employed,the signal received by the relay is retransmitted after it passes through a linear filter.The objective of the paper is to concurrently design optimal recursive filters for FFSR and stochastic systems against switching characteristics and IRI of relays.First,a uniform measurement model is proposed by analyzing the transmission mechanism of FFSR.Then,novel filter structures with switching parameters are constructed for both FFSR and stochastic systems.With the help of the inductive method,filtering error covariances are presented in the form of coupled difference equations.Next,the desired filter gain matrices are further obtained by minimizing the trace of filtering error covariances.Moreover,the stability performance of the filtering algorithm is analyzed where the uniform bound is guaranteed on the filtering error covariance.Finally,the effectiveness of the proposed filtering method over FFSR is verified by a three-order resistance-inductance-capacitance circuit system. 展开更多
关键词 FILTERING successive STOCHASTIC
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Group-Based Successive Interference Cancellation for Multi-Antenna NOMA System with Error Propagation 被引量:1
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作者 Cheng Hu Hong Wang +1 位作者 Changxiang Li Rongfang Song 《China Communications》 SCIE CSCD 2023年第8期276-287,共12页
Non-orthogonal multiple access(NOMA)is viewed as a key technique to improve the spectrum efficiency and solve the issue of massive connectivity.However,for power domain NOMA,the required overall transmit power should ... Non-orthogonal multiple access(NOMA)is viewed as a key technique to improve the spectrum efficiency and solve the issue of massive connectivity.However,for power domain NOMA,the required overall transmit power should be increased rapidly with the increasing number of users in order to ensure that the signal-to-interference-plus-noise ratio reaches a predefined threshold.In addition,since the successive interference cancellation(SIC)is adopted,the error propagation would become more serious as the order of SIC increases.Aiming at minimizing the total transmit power and satisfying each user’s service requirement,this paper proposes a novel framework with group-based SIC for the deep integration between power domain NOMA and multi-antenna technology.Based on the proposed framework,a joint optimization of power control and equalizer design is investigated to minimize transmit power consumption for uplink multi-antenna NOMA system with error propagations.Based on the relationship between the equalizer and the transmit power coefficients,the original problem is transformed to a transmit power optimization problem,which is further addressed by a parallel iteration algorithm.It is shown by simulations that,in terms of the total power consumption,the proposed scheme outperforms the conventional OMA and the existing cluster-based NOMA schemes. 展开更多
关键词 multi-antenna NOMA group-based successive interference cancellation error propagation power control
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THE FEKETE-SZEG?INEQUALITY AND SUCCESSIVE COEFFICIENTS DIFFERENCE FOR A SUBCLASS OF CLOSE-TO-STARLIKE MAPPINGS IN COMPLEX BANACH SPACES 被引量:1
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作者 徐庆华 方炜康 +1 位作者 冯伟珩 刘太顺 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期2075-2088,共14页
Let C be the familiar class of normalized close-to-convex functions in the unit disk.In[17],Koepf demonstrated that,as to a function■in the class C,■By applying this inequality,it can be proven that‖a3|-|a2‖≤1 fo... Let C be the familiar class of normalized close-to-convex functions in the unit disk.In[17],Koepf demonstrated that,as to a function■in the class C,■By applying this inequality,it can be proven that‖a3|-|a2‖≤1 for close-to-convex functions.Now we generalized the above conclusions to a subclass of close-to-starlike mappings defined on the unit ball of a complex Banach space. 展开更多
关键词 Fekete and Szego inequality successive coefficients difference bound close-to-starlike mappings complex Banach space
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A 5MS/s 12-Bit Successive Approximation Analog-to-Digital Converter
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作者 Qinghong Li Xianguo Cao +2 位作者 Liangbin Wang Zechu He Weiming Liu 《Open Journal of Applied Sciences》 2023年第10期1778-1786,共9页
With the continuous development of science and technology, digital signal processing is more and more widely used in various fields. Among them, the analog-to-digital converter (ADC) is one of the key components to co... With the continuous development of science and technology, digital signal processing is more and more widely used in various fields. Among them, the analog-to-digital converter (ADC) is one of the key components to convert analog signals to digital signals. As a common type of ADC, 12-bit sequential approximation analog-to-digital converter (SAR ADC) has attracted extensive attention for its performance and application. This paper aims to conduct in-depth research and analysis of 12-bit SAR ADC to meet the growing demands of digital signal processing. This article designs a 12-bit, successive approximation analog-to-digital converter (SAR ADC) with a sampling rate of 5 MS/s. The overall circuit adopts a fully differential structure, with key modules including DAC capacitor array, comparator, and control logic. According to the DAC circuit in this paper, a fully differential capacitor DAC array structure is proposed to reduce the area of layout DAC. The comparator uses a digital dynamic comparator to improve the ADC conversion speed. The chip is designed based on the SMIC180 nm CMOS process. The simulation results show that when the sampling rate is 5 MS/s, the effective bit of SAR ADC is 11.92 bit, the SNR is 74.62 dB, and the SFDR is 89.24 dB. 展开更多
关键词 successive Approximation Analog-to-Digital Converter SEGMENTED Capacitor Array
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Correlation of personality with individual reproductive success in shrub-nesting birds depends on their life history style
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作者 Jianchuan Li Wen Zhang +5 位作者 Ningning Sun Yujie Wang Lifang Gao Ran Feng Liqing Fan Bo Du 《Avian Research》 SCIE CSCD 2024年第1期42-49,共8页
Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain ... Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain unresolved.We addressed these two questions in three shrub-nesting birds,the Azure-winged Magpie(Cyanopica cyanus,AM),White-collared Blackbird(Turdus albocinctus,WB),and Brown-cheeked Laughingthrush(Trochalopteron henrici,BL).The personality type of an individual was first identified according to its response to a territorial intruder.Then,we compared the fleeing distance,breeding parameters,and differential expressed genes(DEGs) in the brain transcriptome between bold and shy breeders.In the three species,bold breeders exhibited more aggressiveness towards an intruder of their territory than did shy breeders.The reproductive success of bold breeders was significantly higher than that of shy breeders in AM but not in WB and BL.The three species shared one DEG,crabp1,which was up-regulated in bold relative to in shy individuals.By regulating the expression of corticotropin-releasing hormone,higher crabp1 gene expression can decrease cellular response to retinoic acid.Therefore,bold individuals are insensitive to external stresses and able to exhibit more aggressiveness to intruders than their shier counterparts.Aggressiveness is beneficial to bold individuals in AM but not in WB and BL because the former could evoke neighbors to make the same response of defending against intruders but the latter could not.Although a personality trait may have the same genetic basis across species,its correlation with reproductive success depends largely on the life history style of a species. 展开更多
关键词 BOLDNESS Life history style PERSONALITY Reproductive success Transcriptome analysis
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The Emergence of Loving Pedagogy in the L2 Affective Domain:How Affective Pedagogy Accounts for Chinese EFL Teachers’Professional Success and Job Satisfaction?
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作者 Yi Li Xinpeng Wang 《International Journal of Mental Health Promotion》 2024年第3期239-250,共12页
The success of teachers in professional environments has a desirable influence on their mental condition.Simply said,teachers’professional success plays a crucial role in improving their mental health.Due to the inva... The success of teachers in professional environments has a desirable influence on their mental condition.Simply said,teachers’professional success plays a crucial role in improving their mental health.Due to the invaluable role of professional success in teachers’mental health,personal and professional variables helping teachers succeed in their profession need to be uncovered.While the role of teachers’personal qualities has been well researched,the function of professional variables has remained unknown.To address the existing gap,the current investigation measured the role of two professional variables,namely job satisfaction and loving pedagogy,in Chinese EFL teachers’professional success.To do this,three validated scales were provided to 1591 Chinese EFL teachers.Participants’answers to the questionnaires were analyzed using the Spearman correlation test and structural equation modeling.The data analysis demonstrated a strong,positive link between the variables.Moreover,loving pedagogy was found to be the positive,strong predictor of Chinese EFL teachers’job satisfaction and professional success.The findings of the current inquiry may help educational administrators enhance their instructors’professional success,which in turn promotes their mental and psychological conditions at work. 展开更多
关键词 Professional success mental health psychological condition loving pedagogy job satisfaction EFL teachers
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An Evaluation of the Critical Success Factors in Sustainable Food Supply Chains in Developing Countries
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作者 Muhammad Ahasan Habib Deen Islam Preyo +1 位作者 Muhammad Kamruzzaman Ahasan Md. Maruf Hossain 《World Journal of Engineering and Technology》 2024年第3期466-492,共27页
Food is one of the biggest industries in developed and underdeveloped countries. Supply chain sustainability is essential in established and emerging economies because of the rising acceptance of cost-based outsourcin... Food is one of the biggest industries in developed and underdeveloped countries. Supply chain sustainability is essential in established and emerging economies because of the rising acceptance of cost-based outsourcing and the growing technological, social, and environmental concerns. The food business faces serious sustainability and growth challenges in developing countries. A comprehensive analysis of the critical success factors (CSFs) influencing the performance outcome and the sustainable supply chain management (SSCM) process. A theoretical framework is established to explain how they are used to examine the organizational aspect of the food supply chain life cycle analysis. This study examined the CSFs and revealed the relationships between them using a methodology that included a review of literature, interpretative structural modeling (ISM), and cross-impact matrix multiplication applied in classification (MICMAC) tool analysis of soil liquefaction factors. The findings of this research demonstrate that the quality and safety of food are important factors and have a direct effect on other factors. To make sustainable food supply chain management more adequate, legislators, managers, and experts need to pay attention to this factor. In this work. It also shows that companies aiming to create a sustainable business model must make sustainability a fundamental tenet of their organization. Practitioners and managers may devise effective long-term plans for establishing a sustainable food supply chain utilizing the recommended methodology. 展开更多
关键词 Supply Chain Collaboration Interpretative Structural Modeling Cross-Impact Matrix Multiplication SUSTAINABILITY Critical success Factors Multi-Criteria Decision Making Technique for Order of Preference by Similarity to Idea Solution
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Ordered successive noise projection cancellation algorithm for dual lattice-reduction-aided MIMO detection 被引量:2
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作者 刘金铸 邢松 沈连丰 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期229-234,共6页
A novel nonlinear multi-input multi-output MIMO detection algorithm is proposed which is referred to as an ordered successive noise projection cancellation OSNPC algorithm. It is capable of improving the computation p... A novel nonlinear multi-input multi-output MIMO detection algorithm is proposed which is referred to as an ordered successive noise projection cancellation OSNPC algorithm. It is capable of improving the computation performance of the MIMO detector with the conventional ordered successive interference cancellation OSIC algorithm. In contrast to the OSIC in which the known interferences in the input signal vector are successively cancelled the OSNPC successively cancels the known noise projections from the decision statistic vector. Analysis indicates that the OSNPC is equivalent to the OSIC in error performance but it has significantly less complexity in computation.Furthermore when the OSNPC is applied to the MIMO detection with the preprocessing of dual lattice reduction DLR the computational complexity of the proposed OSNPC-based DLR-aided detector is further reduced due to the avoidance of the inverse of the reduced basis of the dual lattice in computation compared to that of the OSIC-based one. Simulation results validate the theoretical conclusions with regard to both the performance and complexity of the proposed MIMO detection scheme. 展开更多
关键词 ordered successive noise projection cancellation(OSNPC) dual lattice reduction (DLR) multi-input multi-output (MIMO) detection ordered successive interferencecancellation (OSIC)
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Capacitor self-calibration technique used in time-interleaved successive approximation ADC
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作者 殷勤 戚韬 +1 位作者 吴光林 吴建辉 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期164-168,共5页
A capacitor self-calibration circuit used in a successive approximation analog-to-digital converter (SA-ADC) is presented. This capacitor self-calibration circuit can calibrate erroneous data and work with the ADC b... A capacitor self-calibration circuit used in a successive approximation analog-to-digital converter (SA-ADC) is presented. This capacitor self-calibration circuit can calibrate erroneous data and work with the ADC by adding an additional clock period. This circuit is used in a 10 bit 32 Msample/s time-interleaved SA- ADC. The chip is implemented with Chart 0. 25 μm 2. 5 V process and totally occupies an area of 1.4 mm× 1.3 mm. After calibration, the simulated signal-to-noise ratio (SNR) is 59. 586 1 dB and the spurious-free dynamic range (SFDR) is 70. 246 dB at 32 MHz. The measured signal-to-noise and distortion ratio (SINAD) is 44. 82 dB and the SFDR is 63. 760 4 dB when the ADC samples a 5.8 MHz sinusoid wave. 展开更多
关键词 capacitor self-calibration analog-to-digital converter successive approximation time-interleaved
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A Polarized Radiative Transfer Model Based on Successive Order of Scattering 被引量:16
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作者 段民征 Qilong MIN 吕达仁 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第4期891-900,共10页
Based on Successive Order of Scattering approach, a full Vector Radiative Transfer model (SOSVRT) for vertically inhomogeneous plane-parallel media has been developed. To overcome the computational burdens of conver... Based on Successive Order of Scattering approach, a full Vector Radiative Transfer model (SOSVRT) for vertically inhomogeneous plane-parallel media has been developed. To overcome the computational burdens of convergence, a simple approximation technique by truncating scattering orders with a geometric series is used to reduce computational time. Analytical Fourier decomposition of phase matrix with three symmetry relationships and two mutual inverse operators have been implemented to further improve the computational efficiency. To improve the accuracy, a post-processing procedure is implemented to accurately interpolate the Stokes vector at arbitrary angles. Comparisons with the benchmarks for an atmosphere of randomly orientated oblate spheroids show excellent agreement for each Stokes parameter (within 0.1%). SOSVRT has been tested for different atmospheric condition against RT3, which is based on doubling-adding method, and the results prove that SOSVRT is accurate and much more efficient in vector radiative transfer modeling, especially for optical thin atmosphere, which is the most common case in polarized radiative transfer simulations. SOSVRT is written in Fortran 90 and the code is freely accessible by contacting the author. 展开更多
关键词 radiative transfer POLARIZATION successive order of scattering SCATTERING
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Response of successive three generations of cotton,bollworm,Helicoverpa armigera (Hübner),fed on cotton bolls under elevated CO_2 被引量:5
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作者 WU Gang CHEN Fa-jun +1 位作者 SUN Yu-cheng GE Feng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第11期1318-1325,共8页
The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera (Htibner), fed on cotton bolls grown under elevated CO2 (double-ambient vs. ambient) in open-top cha... The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera (Htibner), fed on cotton bolls grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere. 展开更多
关键词 elevated CO2 Helicoverpa armigera growth development FECUNDITY cotton bolls population consumption successive generation
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Relationship between rooting ability and endogenous phytohormone changes in successive continuous generation cuttings of Buxus sinica var. parvifolia, an endangered woody species in China 被引量:7
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作者 Huang Yan Ji Kong-shu Zhai Jin-ru 《Forestry Studies in China》 CAS 2007年第3期189-197,共9页
The objectives of this study were to investigate the effects of successive continuous generation (SCG) cuttings of Buxus sinica var. parvifolia on the rejuvenation of ortets at the hormone level, detect levels of in... The objectives of this study were to investigate the effects of successive continuous generation (SCG) cuttings of Buxus sinica var. parvifolia on the rejuvenation of ortets at the hormone level, detect levels of indoleacetic acid (IAA), abscisic acid (ABA), isopentenyladenosine (iPA), zeatin riboside (ZR) and gibberellin4 (GA4) during the rooting process of different generations by means of enzyme-linked immunosorbent assay (ELISA) technology and statistically analyze the rooting characteristics of cuttings. The results show that, the root systems of subsequent generations (generation 1998, 2000) developed satisfactorily, only a few initial generation (generation 1990, 1994) cuttings rooted and the root growth was inhibited. Around the period of callus formation and root projection through the epidermis, there was a marked, regular variation in the levels of IAA, ABA and GA4 between the initial generations and subsequent generations. 展开更多
关键词 Buxus sinica var. parvifolia PHYTOHORMONES successive continuous generation cutting REJUVENATION
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Mismatch Calibration Techniques in Successive Approximation Analog-to-Digital Converters
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作者 王沛 龙善丽 吴建辉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第9期1369-1374,共6页
Comparator offset cancellation and capacitor self-calibration techniques used in a successive approximation analog-to-digital converter (SA-ADC) are described. The calibration circuit works in parallel with the SAAD... Comparator offset cancellation and capacitor self-calibration techniques used in a successive approximation analog-to-digital converter (SA-ADC) are described. The calibration circuit works in parallel with the SAADC by adding additional calibration clock cycles to pursue high accuracy and low power consumption, and the calibrated resolution can be up to 14bit. This circuit is used in a 10bit 3Msps successive approximation ADC. This chip is realized with an SMIC 0. 18μm 1.8V process and occupies 0.25mm^2 . It consumes 3. 1mW when operating at 1.8MHz. The measured SINAD is 55. 9068dB, SFDR is 64. 5767dB, and THD is - 74. 8889dB when sampling a 320kHz sine wave. 展开更多
关键词 analog-to-digital converter successive approximation self-calibration techniques
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Successive lag synchronization on dynamical networks with communication delay 被引量:2
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作者 张新建 韦爱举 李科赞 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第3期466-472,共7页
In this paper, successive lag synchronization (SLS) on a dynamical network with communication delay is investigated. In order to achieve SLS on the dynamical network with communication delay, we design linear feedba... In this paper, successive lag synchronization (SLS) on a dynamical network with communication delay is investigated. In order to achieve SLS on the dynamical network with communication delay, we design linear feedback control and adaptive control, respectively. By using the Lyapunov function method, we obtain some sufficient conditions for global stability of SLS. To verify these results, some numerical examples are further presented. This work may find potential applications in consensus of multi-agent systems. 展开更多
关键词 successive lag synchronization dynamical network communication delay feedback control
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Biomass Productivity of Taiwania flousiana Plantation and Successive Rotation Plantation of Cunninghamia lanceolata in Cutover Forest Land of C.Lanceolata 被引量:5
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作者 Kai LIU Jiaguo WEI +3 位作者 Bin HE Ji LIANG Fansheng LIU Zhengwen YANG 《Agricultural Biotechnology》 CAS 2018年第4期178-180,186,共4页
[Objectives] The aim was to reveal the accumulation characteristics and differences of biomass productivity of Taiwania flousiana plantation and successive rotation plantation of Cunninghamia lanceolata .[Methods] The... [Objectives] The aim was to reveal the accumulation characteristics and differences of biomass productivity of Taiwania flousiana plantation and successive rotation plantation of Cunninghamia lanceolata .[Methods] The biomass and productivity of the 23-year-old T. flousiana plantation and successive rotation plantation of C. lanceolata were studied at Nandan Shankou Forestry Farm of Guangxi., China.[Results] There were differences in the biomass distribution of different organs of T. flousiana plantation and successive rotation plantation of C.lanceolata. The biomass for the T. flousiana plantation was distributed in the order of stem 〉 branch 〉 leaves 〉 bark, and the successive rotation plantations of C. lanceolata was stem〉 root 〉 branch 〉 bark 〉 leaves. The biomass of tree layer of 23-years-old T. flousiana plantation and successive rotation plantations were 195.21 and 136.82 t/hm^2, respectively, including 113.32 and 87.91 t/hm^2 of economic biomass (stem). The annual net productivity of tree layer of the 2 plantations were 8.49 and 5.95 t/(hm^2·a), respectively, including 5.14 and 3.82 t/(hm^2·a) of stem. Therefore, T. flousiana plantation has higher biomass accumulation ability than that of successive rotation plantations of C.lanceolata, and can be used as an excellent substitute tree species for the regeneration of C.lanceolata cutover plantation.[Conclusions] 展开更多
关键词 Taiwania flousiana Cunninghamia lanceolata successive rotation BIOMASS PRODUCTIVITY
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Successive lag cluster consensus on multi-agent systems via delay-dependent impulsive control 被引量:1
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作者 Xiao-Fen Qiu Yin-Xing Zhang Ke-Zan Li 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第5期38-47,共10页
We introduce a new consensus pattern, named a successive lag cluster consensus(SLCC), which is a generalized pattern of successive lag consensus(SLC). By applying delay-dependent impulsive control, the SLCC of first-o... We introduce a new consensus pattern, named a successive lag cluster consensus(SLCC), which is a generalized pattern of successive lag consensus(SLC). By applying delay-dependent impulsive control, the SLCC of first-order and second-order multi-agent systems is discussed. Furthermore, based on graph theory and stability theory, some sufficient conditions for the stability of SLCC on multi-agent systems are obtained. Finally, several numerical examples are given to verify the correctness of our theoretical results. 展开更多
关键词 successive LAG CLUSTER CONSENSUS IMPULSIVE control multi-agent systems
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Acid Release from an Acid Sulfate Soil Sample Under Successive Extractions with Different Extractants 被引量:5
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作者 C.LIN M.M.ISLAM 《Pedosphere》 SCIE CAS CSCD 2000年第3期221-228,共8页
An acid sulfate soil sample was successively extracted with deionized water, 1 mol L-1 KCl and 0.000 5 mol L-l Ca(OH)2 solutions. The results showed that only very small amounts of acidity were extracted by deionized ... An acid sulfate soil sample was successively extracted with deionized water, 1 mol L-1 KCl and 0.000 5 mol L-l Ca(OH)2 solutions. The results showed that only very small amounts of acidity were extracted by deionized water, possibly through slow jarosite hydrolysis. Acid release through jarosite hydrolysis was greatly enhanced by Ca(OH)2 extraction at the expense of the added OH- being neutralized by the acid released. Successive extraction of the sample with KCl removed the largest amounts of acidity from the sample. However, it is likely that the major form of acidity released by KCl extraction was exchangeable acidity. The results also show the occurrence of low or non charged Al and Fe species in water and Ca(OH)2 extracts after first a few extractions. It appears that such a phenomenon was related to a decreasing EC value with increasing number of extractions. 展开更多
关键词 acid release acid sulfate soil successive extractio`
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Over-relaxation effect of deformed austenite on ageing behavior of an Nb-bearing microalloyed steel 被引量:4
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作者 ShaoqiangYuan ShanwuYang +1 位作者 XueminWang XinlaiHe 《Journal of University of Science and Technology Beijing》 CSCD 2005年第3期248-251,共4页
The ageing behavior of an Nb-bearing microalloyed steel at 525℃ was investigated by thermo-simulation test, hardness measurements and transmission electron microscopy (TEM). Prior to ageing, the steel was deformed in... The ageing behavior of an Nb-bearing microalloyed steel at 525℃ was investigated by thermo-simulation test, hardness measurements and transmission electron microscopy (TEM). Prior to ageing, the steel was deformed in austenite zone followed by a long relaxation. Experimental results indicate that the hardness decreases gradually in the initial stage until ageing for 120 min, and then increases continuously until 1200 min. The coarsened precipitates (>10 nm) formed in deformed austenite remain nearly unchanged in size, even after ageing for long time, while the further precipitates, which nucleate in a phase, contribute to the increasing of hardness. By comparison, the undeformed samples in austenite subjected to the same ageing process display a very similar hardness change trend to that of over-relaxation ones and have higher hardness values at each corresponding period. 展开更多
关键词 over-relaxation ageing HARDNESS PRECIPITATES
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MHD flow of upper-convected Maxwell fluid over porous stretching sheet using successive Taylor series linearization method 被引量:3
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作者 S.S.MOTSA T.HAYAT O.M.ALDOSSARY 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第8期975-990,共16页
This paper investigates the magnetohydrodynamic (MHD) boundary layer flow of an incompressible upper-convected Maxwell (UCM) fluid over a porous stretching surface. Similarity transformations are used to reduce th... This paper investigates the magnetohydrodynamic (MHD) boundary layer flow of an incompressible upper-convected Maxwell (UCM) fluid over a porous stretching surface. Similarity transformations are used to reduce the governing partial differential equations into a kind of nonlinear ordinary differential equations. The nonlinear prob- lem is solved by using the successive Taylor series linearization method (STSLM). The computations for velocity components are carried out for the emerging parameters. The numerical values of the skin friction coefficient are presented and analyzed for various parameters of interest in the problem. 展开更多
关键词 upper-convected Maxwell (UCM) fluid boundary layer flow successivelinearization method successive Taylor series linearization method (STSLM)
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New Formulas of Earth Pressure on Large Successive Cylinders 被引量:1
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作者 Wang, YZ Meng, QW 《China Ocean Engineering》 SCIE EI 1998年第4期443-452,共10页
The retaining wall made of large successive cylinders is a kind of structure which draws much attention in coastal engineering of China. The earth pressure on the arched back of large successive cylinders is different... The retaining wall made of large successive cylinders is a kind of structure which draws much attention in coastal engineering of China. The earth pressure on the arched back of large successive cylinders is different from that on the plane back of a general wall. On the basis of equilibrium of forces on the strip element taken from the soil between two cylinders, the differential equation is established and the analytic solution to the equation is obtained. The formulas of earth pressure on large successive cylinders are given in this paper. The distribution of earth pressure around the circle given by the present formulas is different from that given by the formulas commonly used at present, but it is identical with that measured in the model test. 展开更多
关键词 successive cylinders earth pressure analytic solution
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