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Throughput Analysis of HARQ Scheme Based on Full-Duplex Two-Way AF SWIPT Relay

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Computers, Materials & Continua 2023年第3期74卷 4819-4830页

作者： Xiaoye Shi fei ding Haiting Zhu Zhaowei Zhang Lei Zhang School of Internet of Things(Nanjing University of Posts and Telecommunications) Nanjing210003China Department of Electronic and Electrical Engineering(University College London) LondonWC1E6BTUK

The simultaneous wireless information and power transfer(SWIPT)relay system is one of the emerging *** Corporation and Motorola *** launched indoor wireless power transfer equipment is one of the most promising *** tap the potential of the system,hybrid automatic repeat request(HARQ)is introduced into the SWIPT relay ***,the time slot structure of HARQ scheme based on full duplex two-way amplify and forward(AF)SWIPT relay is given,and its retransmission status is ***,the equivalent signal-to-noise ratio and outage probability of various states are calculated by approximate ***,the energy harvesting power in each state is ***,the energy harvested-throughput sum function is constructed to characterize the performance of energy harvesting and data *** results show that the proposed HARQ scheme has better energy harvestedthroughput sum function than the traditional HARQ *** P_(2)=22 dB,the maximum sum function is 54.86%(the proposed HARQ scheme)and 52.307%(the traditional HARQ scheme),respectively.

关键词： SWIPT relay HARQ throughput full-duplex

Antiosteoporotic Tetrahydroxanthone Dimers from Aspergillus brunneoviolaceus FB-2 Residing in Human Gut

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Chinese Journal of Chemistry 2021年第6期39卷 1580-1586页

作者： Xiao-Jing Lv fei ding Ying-Jie Wei Ren-Xiang Tan State Key Laboratory Cultivation Base for TCM Quality and Efficacy Nanjing University of Chinese MedicineNanjingJiangsu 210023China State Key Laboratory of Pharmaceutical Biotechnology School of Life SciencesNanjing UniversityNanjingJiangsu 210023China

A complex community of human-associated microorganisms plays diversely important roles in maintaining health,and the metabolites help to define whether a particular human-associated microbe is a friend or a *** work shows that Aspergillus brunneoviolaceus FB-2,derived from the stool of a healthy individual,produces a family of antiosteoporotic xanthone dinners including penibishexahydroxanthone A(1)and brunneoxanthones A-E(2-6,undescribed previously).The structures of 1-6 were elucidated by MS and NMR spectroscopic analysis,and the absolute configuration of 2 was established by X-ray *** 4-6 are relatively rare examples of highly oxidized heterodimeric xanthones with an 8-ketone ***,the prednisolone-induced osteoporotic zebrafish enabled our demonstration that the antiosteoporotic effects of 1-6 are dose-dependent.

关键词： Aspergillus brunneoviolaceus Gut-associated fungus Natural products Structure elucidation Biological activity

FTIR-ATR chamber for observation of efflorescence and deliquescence processes of NaClO_(4) aerosol particles on ZnSe substrate

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Chinese Science Bulletin 2005年第19期50卷 2149-2152页

作者： ZHANG Yunhong HU Yong'an ding fei ZHAO Lijun Department of Chemistry School of Science Beijing Institute of Tech-nology Beijing 100081 China

NaClO4 aerosol particles with diameter of 5―20 microns are deposited on the ZnSe substrate. An FTIR-ATR chamber on the ZnSe substrate is set up to ob-serve the structural changes of NaClO4 aerosol particles at crystallization relative humidity (CRH) and deliquescence relative humidity (DRH). With the decrease of RH (relative humidity) from 96% to 24% in the efflorescence process, the absorbance of O-H stretching band of the aerosol solutions continuously decreases. A sudden decrease of the water peak is observed at RH20%, where solid particles form. Very small amount of residual interfacial water, with two weak peaks at 3602 and 3533 cm-1, can still be resolved in the FTIR-ATR spectra of the solid particles. In the deliquescence process of the same sample, little spectral changes are ob-served when the value of RH varies from 5% to 29%. Before the abrupt increase of the O-H stretching band at the DRH of about RH46%, a pre-deliquescence process is observed, i.e. in the RH range between 33% and 46%, there is really a slow absorbance increase for the peak area of O-H stretching band. The O-H stretching band shows an arciform O-H en-velope, totally different from not only the FTIR-ATR spectra of ClO4? solutions either under supersaturated state or in diluted state, but also the characteristic of the residually in-terfacial water discussed in the efflorescence process. Such kind of water is considered as pure water, indicating that small amount of water aggregates in the microspaces of solid aerosol particles due to the capillary cohesion effect. When the RH arrives at RH44%, two weak shoulders at 3384 and 3260 cm?1 can be resolved, and the solid NaClO4 particles begin to be dissolved by increasing capillary cohesion water. The spectral characteristic of the ν3-ClO4? band also shows the transition from solid particles to mainly solvated ClO4? ions.

关键词： FTIR-ATR 气溶胶毛细管凝聚 NaClO4 风化作用潮解作用

Optimizing radial basis function neural network based on rough sets and affinity propagation clustering algorithm

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第2期13卷 131-138页

作者： Xin-zheng XU Shi-fei ding Zhong-zhi SHI Hong ZHU School of Computer Science and Technology China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Intelligent information Processing Institute of Computing TechnologyChinese Academy of SciencesBeijing 100190China

A novel method based on rough sets (RS) and the affinity propagation (AP) clustering algorithm is developed to optimize a radial basis function neural network (RBFNN). First, attribute reduction (AR) based on RS theory, as a preprocessor of RBFNN, is presented to eliminate noise and redundant attributes of datasets while determining the number of neurons in the input layer of RBFNN. Second, an AP clustering algorithm is proposed to search for the centers and their widths without a priori knowledge about the number of clusters. These parameters are transferred to the RBF units of RBFNN as the centers and widths of the RBF function. Then the weights connecting the hidden layer and output layer are evaluated and adjusted using the least square method (LSM) according to the output of the RBF units and desired output. Experimental results show that the proposed method has a more powerful generalization capability than conventional methods for an RBFNN.

关键词： Radial basis function neural network (RBFNN) Rough sets Affinity propagation Clustering

Microstructure evolution in grey cast iron during directional solidification

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International Journal of Minerals,Metallurgy and Materials 2017年第8期24卷 884-890页

作者： Xian-fei ding Xiao-zheng Li Qiang Feng Warkentin Matthias Shi-yao Huang National Center for Materials Service Safety University of Science and Technology Beijing Beijing Key Laboratory of Special Melting and Preparation of High-end Metal University of Science and Technology Beijing State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Ford Research & Advanced Engineering Europe Materials and Process Research Ford Motor Research and Engineering Center

The solidification characteristics and microstructure evolution in grey cast iron were investigated through Jmat-Pro simulations and quenching performed during directional solidification. The phase transition sequence of grey cast iron was determined as L → L + γ→ L + γ + G →γ + G → P(α + Fe_3C) + α + G. The graphite can be formed in three ways: directly nucleated from liquid through the eutectic reaction(L →γ + G), independently precipitated from the oversaturated γ phase(γ→γ + G), and produced via the eutectoid transformation(γ→ G + α). The area fraction and length of graphite as well as the primary dendrite spacing decrease with increasing cooling rate. Type-A graphite is formed at a low cooling rate, whereas a high cooling rate results in the precipitation of type-D graphite. After analyzing the graphite precipitation in the as-cast and transition regions separately solidified with and without inoculation, we concluded that, induced by the inoculant addition, the location of graphite precipitation changes from mainly the γ interdendritic region to the entire γ matrix. It suggests that inoculation mainly acts on graphite precipitation in the γ matrix, not in the liquid or at the solid–liquid front.

关键词： directional solidification grey cast iron phase transition graphite

Synchronous occurrence of gastric cancer and gastrointestinal stromal tumor: A case report and review of the literature

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World Journal of Gastrointestinal Oncology 2023年第10期15卷 1807-1822页

作者： Jie Liu Bin-Jie Huang fei-fei ding Fu-Tian Tang Yu-Min Li Department of General Surgery Lanzhou University Second HospitalLanzhou 730030Gansu ProvinceChina Key Laboratory of the Digestive System Tumors of Gansu Province Lanzhou University Second HospitalLanzhou 730030Gansu ProvinceChina

BACKGROUND To evaluate the clinicopathological features and prognosis of gastric cancer(GC)occurring synchronously with gastrointestinal stromal tumor(GIST).CASE SUMMARY We report 19 patients with concurrent GC and GIST(17 male and 2 female,median age 62 years).GC was most often located in the lower third of the *** was diagnosed preoperatively in four *** was most often located in the gastric body(n=8,42%).The most common growth pattern in GIST was extraluminal(n=12,63%).The positive expression rates of CD117 and CD34 in GIST were 100% and 95%,*** patients with GIST(n=17,89%)were very low or low *** was no recurrence of GIST during *** 3-year cumulative survival rate was 73.9%,and the 5-year cumulative survival rate was 59.2%.The combined analysis of this study and literature reports(47 reports,157 patients)found that GC and GIST were usually located in the lower third(42%)and middle third(51%)of the *** was usually early(stage I:42%),poorly differentiated(42%)intestinal-type adenocarcinoma(51%).GISTs were primarily small in diameter(median:1.2 cm)and very low or low risk(89%).CONCLUSION Synchronous GC and GIST may not be *** have specific clinicopathological characteristics,and may have mutual inhibition in pathogenesis and progression.

关键词： Gastric cancer Gastrointestinal stromal tumor Synchronous occurrence Diagnosis Prognosis Case report

Novel two-directional grid multi-scroll chaotic attractors based on the Jerk system

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Chinese Physics B 2020年第10期29卷 541-549页

作者： Peng-fei ding Xiao-Yi Feng Cheng-Mao Wu School of Electronics and Information Northwestern Polytechnical UniversityXi'an 710072China School of Electronics and Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

A new method is presented to generate two-directional (2D) grid multi-scroll chaotic attractors via a specific form of the sine function and sign function series, which are applied to increase saddle points of index 2. The scroll number in the x-direction is modified easily through changing the thresholds of the specific form of the sine function, while the scroll number in the y-direction is controlled by the sign function series. Some basic dynamical properties, such as equilibrium points, bifurcation diagram, phase portraits, and Lyapunov exponents spectrum are studied. Furthermore, the electronic circuit of the system is designed and its simulation results are given by Multisim 10.

关键词： grid multi-scroll chaotic attractor Jerk system specific form of the sine function circuit implementation

Effects of Sb Addition on Microstructural Evolution and Mechanical Properties of Mg–9Al–5Sn Alloy

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Acta Metallurgica Sinica(English Letters) 2021年第2期34卷 278-288页

作者： Chun-Hua Ma Fu-Sheng Pan ding-fei Zhang Ai-Tao Tang Zhi-Wen Lu College of Materials Science and Engineering Chongqing UniversityChongqing 400045China College of Mechanical and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

The Mg–9Al–5Sn-xSb(x=0.0,0.3,0.6,1.0,1.5 wt%)alloys were prepared by a simple alloying process followed by hot extrusion with an extrusion ratio of *** effects of Sb additions on the microstructure and mechanical properties of the Mg–9 Al–5 Sn alloys were investigated by optical microscopy,X-ray diffraction,transmission electron microscopy,scanning electron microscopy equipped with an energy-dispersive X-ray *** results indicated that the phasesα-Mg matrix,Mg2Sn,Mg_(3)Sb_(2) and Mg17 Al12 exist in the as-cast Sb-containing *** addition results in the precipitation of Mg_(3)Sb_(2).The dendritic size of these alloys decreases with the addition of *** their ultimate tensile strength and yield strength of extruded alloys increase,and their elongation decreases gradually with increasing the content of *** better mechanical properties of the as-extruded alloys were achieved due to the refined grains and the formation of dispersive second phases Mg_(3)Sb_(2).

关键词： Mg–Al–Sn–Sb alloy Microstructure Extrusion Second phase Mechanical properties

Critical damage value of AZ31B magnesium alloy with different temperatures and strain rates

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Rare Metals 2021年第1期40卷 137-142页

作者： Jing-Ren Dong ding-fei Zhang Yu-Feng Dong Fu-Sheng Pan Sen-Sen Chai College of Materials Science and Engineering Chongqing UniversityChongqing 400045China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400045China

The uniaxial tensile tests were carried out at temperature ranging from room temperature(RT)to 523 K under strain rates of 0.001,0.010 and 0.100 s^(-1) to obtain the flow stress of AZ31 B magnesium *** tensile tests were simulated by the finite element method(FEM)to calculate the critical damage values(Dc)of the CockcroftLatham criterion to predict the occurrence of fracture ***,the effects of temperature and strain rate on Dc were analyzed to predict the critical damage value’s *** results demonstrate that the critical damage value changes in the range of *** increases as strain rate decreases at constant temperature,and increases with the increase of temperature under certain strain rate,but is more sensitive to the temperature.

关键词： AZ31 magnesium alloy Cockcroft-Latham Critical damage value Strain rates