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Research on Node Classification Based on Joint Weighted Node Vectors
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作者 Li Dai 《Journal of Applied Mathematics and Physics》 2024年第1期210-225,共16页
Node of network has lots of information, such as topology, text and label information. Therefore, node classification is an open issue. Recently, one vector of node is directly connected at the end of another vector. ... Node of network has lots of information, such as topology, text and label information. Therefore, node classification is an open issue. Recently, one vector of node is directly connected at the end of another vector. However, this method actually obtains the performance by extending dimensions and considering that the text and structural information are one-to-one, which is obviously unreasonable. Regarding this issue, a method by weighting vectors is proposed in this paper. Three methods, negative logarithm, modulus and sigmoid function are used to weight-trained vectors, then recombine the weighted vectors and put them into the SVM classifier for evaluation output. By comparing three different weighting methods, the results showed that using negative logarithm weighting achieved better results than the other two using modulus and sigmoid function weighting, and was superior to directly concatenating vectors in the same dimension. 展开更多
关键词 Node Classification Network Embedding Representation Learning Weighted Vectors Training
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Litter Productivity and Nutrient Return Characteristics of Three Typical Forest Stands in Golden Mountain
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作者 Fengchen Yan Jiang Zhu +2 位作者 Juyang Wu Jinshi Chen Zijun Tian 《Open Journal of Applied Sciences》 2024年第2期353-370,共18页
Objective: The paper aims to analyze the dynamic characteristics of litter production and nutrient return of the forest ecosystems in subtropical areas, and provide a theoretical basis for the nutrient cycling study i... Objective: The paper aims to analyze the dynamic characteristics of litter production and nutrient return of the forest ecosystems in subtropical areas, and provide a theoretical basis for the nutrient cycling study in southwest Hubei Province and carbon sink function of the whole forest ecosystem. Methods: Three typical forest stands (Chinese fir plantation, Cryptomeria fortunei plantation and evergreen and deciduous broad-leaved mixed forest) in Golden Mountain Forest Farm in southwest Hubei Province were investigated and monitored continuously for the litter types and productivity and nutrient return. Results: The annual litter productivity of the three forest stands ranged from 161.77 to 396.26 kg·hm<sup>-2</sup>;Litters of branches, leaves and reproductive organs accounted for 14.14% - 20.85%, 33.26% - 78.33%, 7.52% - 42.18% of the total, respectively;The litter productivity and total litter productivity of each composition in the three forest stands show unimodal or bimodal changes over months, and the total litter productivity reached the highest value in January, April and October respectively. For different nutrient contents of the three forest stands, the common feature is C > N. The order of nutrient return amount from greatest to least is evergreen and deciduous broad-leaved mixed forest, Cryptomeria fortunei plantation and Chinese fir plantation. For different nutrient return amounts, the common feature is C > N, and the nutrient return amounts are 76.51-180.69 kg·hm<sup>-2</sup> and 2.3 - 5.71 kg·hm<sup>-2</sup> respectively. Conclusion: The annual litter productivity and nutrient return amount of the evergreen and deciduous broad-leaved mixed forest are the highest among the three forest stands. Therefore, protecting the evergreen and deciduous broad-leaved mixed forest and studying the litter changes of Chinese fir plantation and Cryptomeria fortunei plantation are of far-reaching significance for the development of sustainable forest management in this region and the further improvement of the carbon sequestration function of the whole forest ecosystem. 展开更多
关键词 Golden Mountain Litter Productivity Nutrient Return Amount Nutrient Content
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Three Subjects and Seven Duties Model:Empowering Informatization Teaching Ability of Pre-Service Teachers
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作者 Jingjuan Shu Dongqi Xu 《Journal of Contemporary Educational Research》 2024年第1期13-24,共12页
By constructing a model,this study seeks to provide suggestions for strengthening pre-service teachers’informatization teaching ability.It aims to answer the following research questions:(1)What do the pre-service te... By constructing a model,this study seeks to provide suggestions for strengthening pre-service teachers’informatization teaching ability.It aims to answer the following research questions:(1)What do the pre-service teachers know about informatization instruction?What is their level of informatization teaching ability?(2)What factors influence pre-service teachers’ability to deliver informatization instruction?How to overcome the obstacles?The inquiry focuses on the theoretical exploration of informatization teaching ability,questionnaire,and interview analysis on the current condition and improvement of pre-service teachers’informatization teaching ability.The data from the questionnaire and interview of the pre-service teachers were evaluated from three dimensions:awareness and attitude towards informatization teaching,knowledge of informatization teaching,and the ability to apply informatization teaching skills innovatively and comprehensively.The 3S-7D(Three Subjects and Seven Duties)model consisting of three subjects and the seven duties that go with them is established.The three subjects include pre-service teachers,teacher educators,and higher education schools.The seven duties involve pre-service teachers demonstrating learning motivation,cross-discipline thinking,and information and communications technology mastery;teacher educators actively constructing informatization teaching practice and formative assessment;and higher education schools providing adequate hardware and software equipment while offering cooperative opportunities with primary and junior schools through institutionalization. 展开更多
关键词 Pre-service teachers Informatization teaching ability 3S-7D model
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The history,research,and application of traditional Chinese medicine(TCM)guidance techniques in the clinical management of chronic
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作者 Tian-Li Song Li-An Liu +1 位作者 Fang-Lin Zhu Chu-Hua Zeng 《History & Philosophy of Medicine》 2024年第1期3-9,共7页
Traditional Chinese guidance techniques are an important part of traditional Chinese medicine and involve integrating three aspects:essence,energy,and spirit,while combining physical movement,breath control,and mental... Traditional Chinese guidance techniques are an important part of traditional Chinese medicine and involve integrating three aspects:essence,energy,and spirit,while combining physical movement,breath control,and mental regulation.Traditional Chinese guidance techniques include Tai Chi,Eight Section Brocade,Five Animal Frolics,Yi Jin Jing,and Liu Zi Jue,among others.In recent years,an increasing number of clinical studies have demonstrated the beneficial effects of guidance techniques on promoting health and well-being safely.This study provides a systematic and comprehensive summary and analysis of the research on the application of Traditional Chinese guidance techniques in the management of chronic diseases,offering valuable insights for future clinical research directions and the integration of these techniques into medical practice. 展开更多
关键词 Daoyin Therapy energy and spirit chronic diseases
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Postoperative adjuvant therapy for hepatocellular carcinoma with microvascular invasion 被引量:2
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作者 Jiang Li Fan Yang +3 位作者 Jian Li Zhi-Yong Huang Qi Cheng Er-Lei Zhang 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第1期19-31,共13页
Hepatocellular carcinoma(HCC)is one of the most lethal tumors in the world.Liver resection(LR)and liver transplantation(LT)are widely considered as radical treatments for early HCC.However,the recurrence rates after c... Hepatocellular carcinoma(HCC)is one of the most lethal tumors in the world.Liver resection(LR)and liver transplantation(LT)are widely considered as radical treatments for early HCC.However,the recurrence rates after curative treatment are still high and overall survival is unsatisfactory.Microvascular invasion(MVI)is considered to be one of the important prognostic factors affecting postoperative recurrence and long-term survival.Unfortunately,whether HCC patients with MVI should receive postoperative adjuvant therapy remains unknown.In this review,we summarize the therapeutic effects of transcatheter arterial chemoembolization,hepatic arterial infusion chemotherapy,tyrosine protein kinase inhibitor-based targeted therapy,and immune checkpoint inhibitors in patients with MVI after LR or LT,aiming to provide a reference for the best adjuvant treatment strategy for HCC patients with MVI after LT or LR. 展开更多
关键词 Microvascular invasion Hepatocellular carcinoma Liver resection Liver transplantation POSTOPERATIVE Adjuvant treatment
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Three-Way Behavioral Decision Making With Hesitant Fuzzy Information Systems:Survey and Challenges 被引量:1
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作者 Jianming Zhan Jiajia Wang +1 位作者 Weiping Ding Yiyu Yao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第2期330-350,共21页
Three-way decision(T-WD)theory is about thinking,problem solving,and computing in threes.Behavioral decision making(BDM)focuses on effective,cognitive,and social processes employed by humans for choosing the optimal o... Three-way decision(T-WD)theory is about thinking,problem solving,and computing in threes.Behavioral decision making(BDM)focuses on effective,cognitive,and social processes employed by humans for choosing the optimal object,of which prospect theory and regret theory are two widely used tools.The hesitant fuzzy set(HFS)captures a series of uncertainties when it is difficult to specify precise fuzzy membership grades.Guided by the principles of three-way decisions as thinking in threes and integrating these three topics together,this paper reviews and examines advances in three-way behavioral decision making(TW-BDM)with hesitant fuzzy information systems(HFIS)from the perspective of the past,present,and future.First,we provide a brief historical account of the three topics and present basic formulations.Second,we summarize the latest development trends and examine a number of basic issues,such as one-sidedness of reference points and subjective randomness for result values,and then report the results of a comparative analysis of existing methods.Finally,we point out key challenges and future research directions. 展开更多
关键词 Hesitant fuzzy information system(HFIS) prospect theory regret theory three-way decision(T-WD)
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PROPERTIES OF SOLUTIONS TO A HARMONIC-MAPPING TYPE EQUATION WITH A DIRICHLET BOUNDARY CONDITION
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作者 陈博 陈正茂 谢君辉 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1161-1174,共14页
In the present paper, we consider the problem {-△u=u^(β_(1))|■u|^(β_(2)),in Ω,u=0,on ■Ω,u>0,in Ω,(0.1) where β_(1), β_(2) > 0 and β_(1) + β_(2) < 1, and Ω is a convex domain in R~n. The existence... In the present paper, we consider the problem {-△u=u^(β_(1))|■u|^(β_(2)),in Ω,u=0,on ■Ω,u>0,in Ω,(0.1) where β_(1), β_(2) > 0 and β_(1) + β_(2) < 1, and Ω is a convex domain in R~n. The existence, uniqueness,regularity and (2-β_(2))/(1-β_(1)-β_(2))-concavity of the positive solutions of the problem(0.1) are proven. 展开更多
关键词 Harmonic-Mappings type equation positive solution existence regularity α-concavity
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Double-Layer-Optimizing Method of Hybrid Energy Storage Microgrid Based on Improved Grey Wolf Optimization
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作者 Xianjing Zhong Xianbo Sun Yuhan Wu 《Computers, Materials & Continua》 SCIE EI 2023年第8期1599-1619,共21页
To reduce the comprehensive costs of the construction and operation of microgrids and to minimize the power fluctuations caused by randomness and intermittency in distributed generation,a double-layer optimizing confi... To reduce the comprehensive costs of the construction and operation of microgrids and to minimize the power fluctuations caused by randomness and intermittency in distributed generation,a double-layer optimizing configuration method of hybrid energy storage microgrid based on improved grey wolf optimization(IGWO)is proposed.Firstly,building a microgrid system containing a wind-solar power station and electric-hydrogen coupling hybrid energy storage system.Secondly,the minimum comprehensive cost of the construction and operation of the microgrid is taken as the outer objective function,and the minimum peak-to-valley of the microgrid’s daily output is taken as the inner objective function.By iterating through the outer and inner layers,the system improves operational stability while achieving economic configuration.Then,using the energy-self-smoothness of the microgrid as the evaluation index,a double-layer optimizing configuration method of the microgrid is constructed.Finally,to improve the disadvantages of grey wolf optimization(GWO),such as slow convergence in the later period and easy falling into local optima,by introducing the convergence factor nonlinear adjustment strategy and Cauchy mutation operator,an IGWO with excellent global performance is proposed.After testing with the typical test functions,the superiority of IGWO is verified.Next,using IGWO to solve the double-layer model.The case analysis shows that compared to GWO and particle swarm optimization(PSO),the IGWO reduced the comprehensive cost by 15.6%and 18.8%,respectively.Therefore,the proposed double-layer optimizationmethod of capacity configuration ofmicrogrid with wind-solar-hybrid energy storage based on IGWO could effectively improve the independence and stability of the microgrid and significantly reduce the comprehensive cost. 展开更多
关键词 Wind-solar microgrid hybrid energy storage optimization configuration double-layer optimization model IGWO
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Thermal spin molecular logic gates modulated by an electric field
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作者 谭兴毅 李强 任达华 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期591-595,共5页
Logic gates are fundamental structural components in all modern digital electronic devices. Here, nonequilibrium Green's functions are incorporated with the density functional theory to verify the thermal spin tra... Logic gates are fundamental structural components in all modern digital electronic devices. Here, nonequilibrium Green's functions are incorporated with the density functional theory to verify the thermal spin transport features of the single-molecule spintronic devices constructed by a single molecule in series or parallel connected with graphene nanoribbons electrodes. Our calculations demonstrate that the electric field can manipulate the spin-polarized current. Then, a complete set of thermal spin molecular logic gates are proposed, including AND, OR, and NOT gates. The mentioned logic gates enable different designs of complex thermal spin molecular logic functions and facilitate the electric field control of thermal spin molecular devices. 展开更多
关键词 thermal spin molecular logic gates electric field SINGLE-MOLECULE
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A novel approach for 25-gauge transconjunctival sutureless vitrectomy to evaluate vitreous substitutes in rabbits
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作者 Rui-Jin Ran Ting Wang +2 位作者 Meng-Ying Tao Yue-Qin Gou Ming Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第10期1568-1573,共6页
AIM:To improve the standard three-port vitrectomy for establishing and evaluating an endotamponade model in rabbits.METHODS:Three ports were prepared near the third eyelid of rabbits,and the infusion port was placed a... AIM:To improve the standard three-port vitrectomy for establishing and evaluating an endotamponade model in rabbits.METHODS:Three ports were prepared near the third eyelid of rabbits,and the infusion port was placed at the inferior nasal quadrant with the inserted cannula linking with a self-designed handheld rigid infusion catheter.All right eyes of rabbits underwent a modified 25-gauge vitrectomy and were subsequently filled with balanced salt solution,silicone oil,and eight-arm polyethylene glycols(8-arm PEGs)hydrogel separately for comparison.Ophthalmic examinations were performed regularly to record the changes after the surgery.RESULTS:Successful vitrectomy was achieved among 44 chinchilla rabbits.The mean operation time was 4.51±1.25min.Four eyes(9.1%)presented limited lens touch and two eyes(4.5%)showed retinal touch during surgery.Incision leakage was found in three eyes(6.8%)after surgery.There was no endophthalmitis,hemorrhage,or retinal detachment during the observation period and ophthalmic examinations after the implantation of vitreous substitutes.CONCLUSION:The modified technique of the standard vitrectomy applied in the endotamponade model in rabbits shows excellent safety and practicality. 展开更多
关键词 surgical technique endotamponade model vitreous substitute three-port vitrectomy RABBIT
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Envelope Method and More General New Global Structures of Solutions for Multi-dimensional Conservation Law
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作者 Gui-Qin Qiu Gao-Wei Cao +1 位作者 Xiao-Zhou Yang Yuan-An Zhao 《Communications on Applied Mathematics and Computation》 2023年第3期1180-1234,共55页
For the two-dimensional(2D)scalar conservation law,when the initial data contain two different constant states and the initial discontinuous curve is a general curve,then complex structures of wave interactions will b... For the two-dimensional(2D)scalar conservation law,when the initial data contain two different constant states and the initial discontinuous curve is a general curve,then complex structures of wave interactions will be generated.In this paper,by proposing and investigating the plus envelope,the minus envelope,and the mixed envelope of 2D non-selfsimilar rarefaction wave surfaces,we obtain and the prove the new structures and classifications of interactions between the 2D non-selfsimilar shock wave and the rarefaction wave.For the cases of the plus envelope and the minus envelope,we get and prove the necessary and sufficient criterion to judge these two envelopes and correspondingly get more general new structures of 2D solutions. 展开更多
关键词 Riemann problem Non-selfsimilar shock wave Non-selfsimilar rarefaction wave ENVELOPE Multi-dimensional conservation law
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Global Dynamics Analysis of a Cholera Transmission Model with General Incidence and Multiple Modes of Infection
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作者 Daijun Li Lianwen Wang 《Journal of Applied Mathematics and Physics》 2023年第11期3747-3759,共13页
This paper develops an SIBR cholera transmission model with general incidence rate. Necessary and sufficient conditions for local and global asymptotic stability of the equilibria are established by Routh Hurwitz crit... This paper develops an SIBR cholera transmission model with general incidence rate. Necessary and sufficient conditions for local and global asymptotic stability of the equilibria are established by Routh Hurwitz criterium, Lyapunov function, and the second additive composite matrix theorem. What is more, exploiting the DED is cover simulation tool, the parameter values of the model are estimated with the 1998-2021 cholera case data in China. Finally, we perform sensitivity analysis for the basic reproduction number to seek for effective interventions for cholera control. . 展开更多
关键词 Cholera Transmission Model Nonlinear Incidence Rate Second Additive Composite Matrix Lyapunov Function Global Stability
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Synthesis, Crystal Structure, and Antitumor Activity of 1-(4-Methoxybenzylidene)-2-(1-phenyl-6-trifluoromethyl-1H-pyrazolo[3,4-d]pyrimidin-4-yl)hydrazine Monohydrate 被引量:2
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作者 杨平 高慧 宋新建 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第8期1129-1134,共6页
The novel title compound 1-(4-methoxybenzylidene)-2-(1-phenyl-6-trifluoromethyl-1H-pyrazolo[3,4-d]pyrimidin-4-yl)hydrazine monohydrate(C20H15F3N6O·H2O, Mr = 430.40) has been synthesized by a four-step procedure i... The novel title compound 1-(4-methoxybenzylidene)-2-(1-phenyl-6-trifluoromethyl-1H-pyrazolo[3,4-d]pyrimidin-4-yl)hydrazine monohydrate(C20H15F3N6O·H2O, Mr = 430.40) has been synthesized by a four-step procedure including the cyclization, chlorination, hydrazinolysis and condensation reaction, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to orthorhombic, space group Pbca with a = 8.3779(13), b = 17.607(3), c = 26.774(4) , V = 3949.2(11) 3, Z = 8, Dc = 1.448 g/cm3, μ = 0.117 mm–1, F(000) = 1776, the final R = 0.0553 and wR = 0.1516 for 2354 observed reflections with I > 2■(I). X-ray diffraction analysis reveals that the title compound is almost coplanar except for the trifluoromethyl and phenyl moieties. In the crystal packing, the molecules are linked by intermolecular O(1W)–H(1WA)···N(2), O(1W)–H(1WA)···N(4) and N(5)–H(5A)···O(1W) hydrogen bonds via water molecules and stacked through π-π stacking interactions. The preliminary bioassay suggested that the title compound exhibits relatively good antitumor activity against HepG2 and BCG-823. 展开更多
关键词 抗肿瘤活性 三氟甲基 晶体结构 甲氧基 水合物 苯基 肼解 合成
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Pachymic Acid Ameliorates Pulmonary Hypertension by Regulating Nrf2-Keap1-ARE Pathway 被引量:7
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作者 Yuan HE Jian-hua ZHONG +6 位作者 Xiao-dong WEI Chu-ying HUANG Pai-lan PENG Jun YAO Xiu-sheng SONG Wan-li FAN Guang-cai LI 《Current Medical Science》 SCIE CAS 2022年第1期56-67,共12页
Objective:Pulmonary hypertension(PH)is a severe pulmonary vascular disease that eventually leads to right ventricular failure and death.The purpose of this study was to investigate the mechanism by which pachymic acid... Objective:Pulmonary hypertension(PH)is a severe pulmonary vascular disease that eventually leads to right ventricular failure and death.The purpose of this study was to investigate the mechanism by which pachymic acid(PA)pretreatment affects PH and pulmonary vascular remodeling in rats.Methods:PH was induced via hypoxia exposure and administration of PA(5 mg/kg per day)in male Sprague-Dawley rats.Hemodynamic parameters were measured using a right ventricular floating catheter and pulmonary vascular morphometry was measured by hematoxylin-eosin(HE),a-SMA and Masson staining.MTT assays and EdU staining were used to detect cell proliferation,and apoptosis was analyzed by TUNEL staining.Western blotting and immunohistochemistry were used to detect the expression of proteins related to the Nrf2-Keapl-ARE pathway. 展开更多
关键词 pulmonary hypertension pachymic acid nuclear factor erythroid 2-related factor 2 Kelch-like epichlorohydrin-related protein 1 antioxidant response element
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Novel DDS Based OFDM Transmitter Structure without IFFT and Interpolation Filter 被引量:2
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作者 Sanjun Liu Guangming Gan 《China Communications》 SCIE CSCD 2021年第12期219-229,共11页
The traditional orthogonal frequency divi-sion multiplexing(OFDM)transmitter is implemented by inverse fast Fourier transform(IFFT),up-sampling and low pass shaping filter(LPSF),which occupy a large number of hardware... The traditional orthogonal frequency divi-sion multiplexing(OFDM)transmitter is implemented by inverse fast Fourier transform(IFFT),up-sampling and low pass shaping filter(LPSF),which occupy a large number of hardware resources and have long la-tency.To further meet the 5G and future 6G commu-nication requirements,this paper proposes a novel di-rect digital synthesis(DDS)based OFDM transmitter structure that can replace these modules.Due to the strong parallelism of the system structure,it is very suitable for implementation on field programable gate array(FPGA)platform.After making two special sim-plifications to the primary structure,the refined struc-ture becomes very simple compared with the tradi-tional structures.Most attractively,the proposed struc-ture has the following three advantages that i)the data transformation from frequency domain to time domain has zero latency,ii)the transformation length does not need to be an integer power of 2 and iii)the struc-ture does not even need to use any multiplier,thus leading to low implementation complexity and high speed.Comparative experiments are carried out on Intel FPGA platform which show that our DDS based structure can save more than half of the resources com-pared with the traditional structures and can provide the same bit error rate(BER)performance under the condition without using any LPSF. 展开更多
关键词 OFDM TRANSMITTER direct digital synthe-sis(DDS) fast Fourier transform(FFT)
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Electronic and optical properties of GaN–MoS2 heterostructure from first-principles calculations 被引量:1
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作者 任达华 谭兴毅 +1 位作者 张腾 张源 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第8期254-257,共4页
Heterostructures(HSs)have attracted significant attention because of their interlayer van der Waals interactions.The electronic structures and optical properties of stacked GaN-MoS2 HSs under strain have been explored... Heterostructures(HSs)have attracted significant attention because of their interlayer van der Waals interactions.The electronic structures and optical properties of stacked GaN-MoS2 HSs under strain have been explored in this work using density functional theory.The results indicate that the direct band gap(1.95 e V)of the Ga N-MoS2 HS is lower than the individual band gaps of both the GaN layer(3.48 e V)and the MoS2 layer(2.03 eV)based on HSE06 hybrid functional calculations.Specifically,the GaN-MoS2 HS is a typical type-II band HS semiconductor that provides an effective approach to enhance the charge separation efficiency for improved photocatalytic degradation activity and water splitting efficiency.Under tensile or compressive strain,the direct band gap of the GaN-MoS2 HS undergoes redshifts.Additionally,the GaN-MoS2 HS maintains its direct band gap semiconductor behavior even when the tensile or compressive strain reaches 5%or-5%.Therefore,the results reported above can be used to expand the application of Ga N-MoS2 HSs to photovoltaic cells and photocatalysts. 展开更多
关键词 GaN-MoS2 HETEROSTRUCTURE ELECTRONIC structures optical properties FIRST-PRINCIPLES CALCULATIONS
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Preparation of Bi_(2)O_(3)/BiOI Step-scheme Heterojunction Photocatalysts and Their Degradation Mechanism of Methylene Blue 被引量:2
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作者 姜雪超 谭海燕 +3 位作者 SHI Xinyu CHENG Xinhua HU Weibing HU Xinhui 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第5期801-806,共6页
Bi_(2)O_(3)/BiOI step-scheme(S-scheme) heterojunction photocatalyst was synthesized by green calcination method, its degradation ability of methylene blue was investigated, and the photocatalytic performance of the Bi... Bi_(2)O_(3)/BiOI step-scheme(S-scheme) heterojunction photocatalyst was synthesized by green calcination method, its degradation ability of methylene blue was investigated, and the photocatalytic performance of the Bi_(2)O_(3)/BiOI heterojunction, Bi_(2)O_(3) and BiOI was compared. The structure and morphology of the samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FESEM), and UV-vis diffuse reflection spectrum (UV-vis DRS). The degradation rate of methylene blue was analysised by spectrophotometry, and the calculation result showed that the degradation rate of methylene blue was 97.8% in 150 minutes. The first order kinetic rate constant of 10%Bi_(2)O_(3)/BiOI is 0.021 8 min^(-1), which are2.37 and 2.68 times of BiOI(0.009 18 min^(-1)) and Bi_(2)O_(3) (0.008 03 min^(-1)) respectively. The calculation result shows that the work function of Bi_(2)O_(3) and BiOI are 3.0 e V and 6.0 e V, respectively, by density functional theory(DFT). When this S-scheme heterojunction is used as a photocatalyst, the weaker electrons in the conduction band of BiOI will be combined with the weaker holes in the Bi_(2)O_(3) valence band under combined effect with built-in electric field and band bending, which will retain stronger photoelectrons and holes between Bi_(2)O_(3) and BiOI. This may be the internal reason for the efficient degradation of tetracycline by Bi_(2)O_(3)/BiOI S-scheme heterostructures. 展开更多
关键词 step-scheme heterojunction methylene blue antibiotic wastewater treatment photocatalytic degradation charge separation
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Tunable electronic structures of germanane/antimonene van der Waals heterostructures using an external electric field and normal strain 被引量:1
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作者 谭兴毅 刘利利 任达华 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第7期393-398,共6页
oscale devices.In the present work,we investigate the electronic structures of germanane/antimonene vdW heterostructure in response to normal strain and an external electric field by using the first-principles calcul... oscale devices.In the present work,we investigate the electronic structures of germanane/antimonene vdW heterostructure in response to normal strain and an external electric field by using the first-principles calculations based on density functional theory(DFT).The results demonstrate that the germanane/antimonene vdW heterostructure behaves as a metal in a[1,,0.6]V/A range,while it is a direct semiconductor in a[0.5,0.2]V/A range,and it is an indirect semiconduc-tor in a[0.3,1.0]V/A range.Interestingly,the band alignment of germanane/antimonene vdW heterostructure appears astype-II feature both in a[0.5,0.1]range and in a[0.3,1]V/A range,while it shows the type-I character at 0.2 V/A.In ad-dition,we find that the germanane/antimonene vdW heterostructure is an indirect semiconductor both in an in-plane biaxial strain range of[[5%,,3%]and in an in-plane biaxial strain range of[3%,5%],while it exhibits a direct semiconductor character in an in-plane biaxial strain range of[2%,2%].Furthermore,the band alignment of the germanane/antimonene vdW heterostructure changes from type-II to type-I at an in-plane biaxial strain of 3%.The adjustable electronic structure of this germanane/antimonene vdW heterostructure will pave the way for developing the nanoscale devices. 展开更多
关键词 germanane/antimonene vdW heterostructure electronic structures external electric field STRAIN first-principles calculations
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PV Power Short-Term Forecasting Model Based on the Data Gathered from Monitoring Network 被引量:1
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作者 ZHONG Zhifeng TAN Jianjun +1 位作者 ZHANG Tianjin ZHU Linlin 《China Communications》 SCIE CSCD 2014年第A02期61-69,共9页
关键词 短期预测模型 光伏发电 网络基础 预测精度 搜集 监测 粒子群算法 经济运行
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Tunable electronic properties of GaS-SnS_(2)heterostructure by strain and electric field 被引量:1
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作者 任达华 李强 +1 位作者 钱楷 谭兴毅 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第4期583-588,共6页
Vertically stacked heterostructures have received extensive attention because of their tunable electronic structures and outstanding optical properties.In this work,we study the structural,electronic,and optical prope... Vertically stacked heterostructures have received extensive attention because of their tunable electronic structures and outstanding optical properties.In this work,we study the structural,electronic,and optical properties of vertically stacked GaS-SnS_(2)heterostructure under the frame of density functional theory.We find that the stacked GaS-SnS_(2)heterostructure is a semiconductor with a suitable indirect band gap of 1.82 eV,exhibiting a type-Ⅱband alignment for easily separating the photo-generated carriers.The electronic properties of GaS-SnS_(2)hetero structure can be effectively tuned by an external strain and electric field.The optical absorption of GaS-SnS_(2)heterostructure is more enhanced than those of the GaS monolayer and SnS_(2)monolayer in the visible light region.Our results suggest that the GaS-SnS_(2)hetero structure is a promising candidate for the photocatalyst and photoelectronic devices in the visible light region. 展开更多
关键词 GaS-SnS_(2)heterostructure type-Ⅱband alignment optical properties density functional theory
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