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A Fairness-Enhanced Intelligent MAC Scheme Using Q-Learning-Based Bidirectional Backoff for Distributed Vehicular Communication Networks

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Tsinghua Science and Technology 2023年第2期28卷 258-268页

作者： Ping Wang Shuai wang College of Information Science and Technology Donghua UniversityShanghai 201620China

With the increasing attention to front-edge vehicular communication applications,distributed resource allocation is beneficial to the direct communications between vehicle nodes.However,in highly dynamic distributed vehicular networks,quality of service(QoS)of the systems would degrade dramatically because of serious packet collisions in the absence of sufficient link knowledge.Focusing on the fairness optimization,a Q-learning-based collision avoidance(QCA)scheme,which is characterized by an ingenious bidirectional backoff reward model RQCA corresponding to arbitrary backoff stage transitions,has been proposed in an intelligent distributed media access control protocol.In QCA,an intelligent bidirectional backoff agent based on the Markov decision process model can actively motivate each vehicle agent to update itself toward an optimal backoff sub-intervel BSIopt through either positive or negative bidirectional transition individually,resulting in the distinct fair communication with a proper balance of the resource allocation.According to the reinforcement learning theory,the problem of goodness evaluation on the backoff stage self-selection policy is equal to the problem of maximizing Q function of the vehicle in the current environment.The final decision on BSI_(opt) related to an optimal contention window range was solved through maximizing the Q value or Q_(max).The ε-greedy algorithm was used to keep a reasonable convergence of the Q_(max) solution.For the fairness evaluation of QCA,four kinds of dynamic impacts on the vehicular networks were investigated:mobility,density,payload size,and data rate with a network simulator NS2.Consequently,QCA can achieve fair communication efficiently and robustly,with advantages of superior Jain’s fairness index,relatively high packet delivery ratio,and low time delay.

关键词： media access control(MAC) fairness Q-learning-based collision avoidance(QCA) bidirectional backoff agent vehicular communication networks

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Investigating Factors Influencing the Stability of Enteral Nutritional Emulsions Designed for Cancer Patients

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Journal of Nutritional Oncology 2021年第3期6卷 140-148页

作者： Qin Qin Li Dan ping Hou Zhuang Ding Sangeeta Prakash Yu Ying Liu Han ping Shi Jun Han Zheng Ping Wang Institute of BioPharmaceutical Liaocheng UniversityLiaocheng252000ShandongChina Liaocheng High-tech Biotechnology Co. Ltd.Liaocheng 252000ShandongChina School of Agriculture&Food Sciences The University of QueenslandBrisbaneQLD 4072Australia Department of Gastrointestinal Surgery/Department of Clinical Nutrition Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China

Objective A commercially available reference product was“re-engineered”and the target emulsion was formulated to contain the same energy density,as well as the same percentage of energy sources,as the reference product.The particle size and distribution,polydispersity index(PDI),and zeta-potential of emulsions were measured as indices to analyse the quality of the emulsions.Methods The centrifugal stability(Ke)was examined as the main measure of the stability of the target emulsion.Critical parameters affecting the stability of emulsions were also determined,while the temperature was fixed at 30℃,shear speed at 3500 r/min,and shear time was 15 min.The optimal quantity of emulsifier was also studied in the crude homogenate.Results A relatively stable emulsion could be obtained by using PC-50 at a dosage of 2%as the emulsifier.A 2∶1 proportion of whey protein to casein,a 1∶1 proportion of maltodextrin(DE 10-15)to maltodextrin(DE 15-20)and medium chain triglyceride(MCT)in powder form were used to obtain the most desirable emulsion.Conclusion This study explored the critical parameters that influence the stability of a total nutrition enteral emulsion designed for cancer patients,providing useful information for further industrialisation of this and other emulsion products.

关键词： Food for Special Medical Purposes Enteral nutritional emulsion Emulsion stability Functional food,Cancer nutrition

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Effects of Orthogonal Heat Treatment on Microstructure and Mechanical Properties of GN9 Ferritic/Martensitic Steel

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 289-300页

作者： Tingwei Ma Xianchao Hao Ping Wang Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110004China Yingkou Institute of Technology Yingkou 115014China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Microstructure and mechanical properties of GN9 Ferritic/Martensitic steel for sodium-cooled fast reactors have been investigated through orthogonal design and analysis.Scanning electron microscopy(SEM),transmission electron microscopy(TEM),differential scanning calorimeter(DSC),tensile and impact tests were used to evaluate the heat treatment parameters on yield strength,elongation and ductile-to-brittle transition temperature(DBTT).The results indicate that the microstructures of GN9 steel after orthogonal heat treatments consist of tempered martensite,M23C6,MX carbides and MX carbonitrides.The average prior austenite grains increase and the lath width decreases with the austenitizing temperature increasing from 1000°C to 1080°C.Tempering temperature is the most important factor that influences the dislocation evolution,yield strength and elongation compared with austenitizing tempera-ture and cooling methods.Austenitizing temperature,tempering temperature and cooling methods show interactive effects on DBTT.Carbide morphology and distribution,which is influenced by austenitizing and tempering tempera-tures,is the critical microstructural factor that influences the Charpy impact energy and DBTT.Based on the orthogo-nal design and microstructural analysis,the optimal heat treatment of GN9 steel is austenitizing at 1000°C for 0.5 h followed by air cooling and tempering at 760°C for 1.5 h.

关键词： Ferritic/Martensitic steel Orthogonal design M23C6 carbide Ductile-to-brittle transition temperature

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王平基于元气理论辨治老年健忘学术经验

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中国中医基础医学杂志 2023年第12期29卷 2076-2078页

作者：李晶王平湖北中医药大学中医临床学院武汉430065 湖北中医药大学老年医学研究所武汉430065

老年健忘主要表现为记忆力减退、遇事易忘,中医也称“喜忘”“善忘”等,属老年群体的常见病、多发病。有些患者还可能发展为阿尔茨海默病,严重影响患者的健康及生活质量。中医药在老年健忘的防治方面具有丰富的临床经验,值得深入探讨。... 详细信息

老年健忘主要表现为记忆力减退、遇事易忘,中医也称“喜忘”“善忘”等,属老年群体的常见病、多发病。有些患者还可能发展为阿尔茨海默病,严重影响患者的健康及生活质量。中医药在老年健忘的防治方面具有丰富的临床经验,值得深入探讨。王平教授从事老年病、老年脑病相关工作多年,对老年健忘的认识深刻、见解独到,常从元气理论出发探讨老年健忘的病因病机及防治措施。王平教授认为老年健忘的病理基础为脾肾亏虚,元气不足;发病的重要因素为元气亏虚,因虚致实,痰阻瘀停;防治方面,认为未病时需培元保元、重在预防,既病则应养元复元、培元健脑。

关键词：老年健忘元气王平病因病机

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Oxygen-contained amorphous MoS_(x) cocatalyst by one-step photodeposition to enhance H-adsorption affinity for efficient photocatalytic H_(2)generation

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Nano Research 2023年第7期16卷 8977-8986页

作者： Pinsi Deng Ping Wang Xuefei wang Feng Chen Huogen Yu School of Chemistry Chemical Engineering and Life SciencesWuhan University of TechnologyWuhan 430070China Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430074China

Traditional bulk MoS_(2) as an effective H_(2)-evolution cocatalyst is mainly subjected to the weak hydrogen-adsorption ability of highporpotion saturated S,resulting in a slow interfacial H_(2)-evolution reaction.In this paper,an efficient strategy for enhancing hydrogen adsorption of saturated S by manipulating electron density through O atoms is proposed to boost photocatalytic performance of CdS.Simultaneously,amorphization of MoS_(2) can further increase the unsaturated active S sites.Herein,oxygencontained amorphous MoS_(x)(a-MoOS_(x))nanoparticles(10-30 nm)were tightly loaded on the CdS surface through a mild photoinduced deposition method by using(NH_(4))_(2)[MoO(S_(4))_(2)]solution as the precursor at room temperature.The photocatalytic H_(2)-evolution result showed that the a-MoOS_(x)/CdS performed the superior H_(2)-production activity(382μmol·h^(-1),apparent quantum efficiencies(AQE)=11.83%)with a lot of visual H_(2)bubbles,which was 54.6,2.5,and 5.1 times as high as that of CdS,MoS_(x)/CdS,and annealed a-MoOS_(x)/CdS,respectively.Characterizations and density functional theory(DFT)calculations revealed the mechanism of improved H_(2)-evolution activity is that the O heteroatom in amorphous MoOS_(x) can enhance the atomic H-adsorption ability by manipulating the electron density to form electron-deficient S^((2-δ)-)sites.This study provides a new idea to improve the efficiency and number of H_(2)-evolution active sites for developing efficient cocatalysts in the field of photocatalytic hydrogen evolution.

关键词： CdS photocatalytic hydrogen evolution cocatalyst oxygen-contained amorphous MoS_(x)(a-MoOS_(x)) atomic hydrogen adsorption

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Green rusts-derived iron oxide nanostructures catalyze NO reduction by CO

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Green Energy & Environment 2023年第2期8卷 499-508页

作者： Ping Wang Xiaoling Mou Yong Li Wenjie Shen Hangzhou Institute of Advanced Studies Zhejiang Normal UniversityHangzhou311231China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China

Green rusts with brucite-like layers of hydroxide intercalated with anions constitute a family of diverse precursors for the synthesis of iron oxides via dehydration,but precise structural control of the resulting oxides with respect to the size and shape at the nanometer level remains challenging due to the easy oxidation of the ferrous species.Herein,we report a new synthetic strategy for the facile preparation of fibrous-like green rusts by using appropriate balancing anions(CO_(3)^(2-)and SO_(4)^(2-))in ethylene glycol to regulate the morphology.Depending on the type of the intercalating anion,the green rusts were converted into hematite with fibrous-or plate-like shapes upon thermal activation.When evaluated in the reaction of NO reduction by CO,these iron oxides showed a prominent shape-dependent catalytic behavior.The fibrous-like Fe_(2)O_(3)was much more catalytically active and structurally robust than the plate-like analogue.Combined spectroscopic and microscopic characterizations on the nanostructured iron oxides revealed that the superior performance of the fibrous-like Fe_(2)O_(3)stemmed from a facile Fe_(2)O_(3)/Fe_(3)O_(4)redox cycle and a higher density of active sites for NO activation.

关键词： Green rust Hematite Morphology NO reduction by CO Redox cycle

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Seizure as the main presenting manifestation of three patients with acute glufosinate-ammonium poisoning

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 354-358页

作者： Ping Wang Congying SONG Xuan LU Yuanqiang LU Deparment of Emergency Medicine the First Afiliated HospitalSchool of MedicineZhejiang UniversiyHangzhou 3100030 China Zhejiang Key Laboratory for Diagnosis and Treatment of Physic chemical and Aging related Injuries Hangzhou 310003China Department of Geriatric Medicine the First Afiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310003China

Glufosinate-ammonium herbicides are the most widely used broad-spectrum,non-selective herbicides in the world.Glufosinate-ammonium is a structural analogue of glutamate(Glu)which can irreversibly inhibit the activity of glutamine synthetase(GS)and Glu decarboxylase in plants,thereby blocking the synthesis of glutamine(Gln)from Glu and ammonia(Hoerlein,1994).This causes the plants to die because of the nitrogen metabolism disorder and subsequent intracellular accumulation of ammonia.In humans,the characteristic features of glufosinate-ammonium herbicide poisoning include gastrointestinal symptoms and neurotoxicity(Watanabe and Sano,1998).

关键词： ammonium ammonia thereby

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Characterizing and identifying bedforms in the wandering reach of the lower Yellow River

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International Journal of Sediment Research 2022年第1期37卷 110-121页

作者： Yuanfeng Zhang Ping Wang Guanqing Shen Yellow River Institute of Hydraulic Research

The lower Yellow River (LYR) is a fully alluvial system with a fine-grained bed that has a high proportion of silt.Bathymetric survey data collected with a Multi-Beam Echo Sounder (MBES) from the wandering reach of the LYR indicates that the bedforms are characterized by large aspect ratios (wavelength/height)and low lee-side angles.Since the Xiaolangdi Reservoir (XLD) has been operational in the middle reach of the Yellow River,bedforms have been dominated by two-scales of dunes,that is,a frame of compound dunes with first-order dunes superimposed on the stoss and lee sides,which disappear during high sediment concentration floods that occur during the annual sediment and water regulation.The bedform formation regime has changed with dune beds having more chances,and upper regime beds having less chances,to form.Longitudinal profile data measured using a sounding-rod before the XLD began filling demonstrate that the bedforms were mainly dunes during low flows (less than 1200 m~3/s) or upper regime beds during high-flows (larger than 2000 m~3/s).A discriminator is proposed to describe the conditions for bedform formation and to predict the alluvial resistance which gives better results than those from Manning approach.When a bedform system is almost at equilibrium,the changes in the sediment concentrations versus the discriminator can be defined into three segments in the LYR.

关键词： Bedform discrimination Two-scales of dunes Alluvial resistance The lower Yellow River

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A Comprehensive Review:Recent Developments of Biomimetic Sensors

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Journal of Bionic Engineering 2022年第4期19卷 853-876页

作者： Xu Ye Yuanyuan Li Yan Zhang Ping Wang National Engineering Laboratory for Modern Silk College of Textile and Clothing EngineeringSoochow UniversitySuzhou 215123China

With the fast development of Internet of Things,flexible and extensible sensors have undergone a great revolution.Because of the limited functions of traditional flexible sensors,more and more researchers begin to develop biomimetic sensors inspired by nature,which introduce unique structures of various natural creatures into sensors through a simple and low-cost process,endowing them with excellent comprehensive properties.By imitating structures,compositions,biological mechanisms of natural organisms,these flaws can be overcome,making sensors have a variety of functions,such as hydrophobicity,discoloration and so on.In this paper,biomimetic objects used in sensors are summarized from three perspectives,plants(lotus leaves),animals(butterfly wings)and components(enzymes).And then,the common preparation methods of biomimetic materials are described in detail,such as template method,hydrothermal method,lithography.Furthermore,the current applications of biomimetic sensors in wearable fields like electronic skin,human health detection and human motion detection,are also generalized.Finally,the difficulties and limitations of sensors,efforts to improve properties of materials,as well as likely future developments were discussed.Hence,it is highly promising to provide readers with a quick glimpse into the research landscape of this field.

关键词： Biomimetic sensors Template Lithography Wearable devices

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Effect of heat treatments on Charpy impact properties of 15Cr12MoVWN ferritic/martensitic steel

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Journal of Iron and Steel Research(International) 2022年第3期29卷 512-518页

作者： Ting-wei Ma Xian-chao Hao Ping Wang Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang110819LiaoningChina Yingkou Institute of Technology Yingkou115014LiaoningChina CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016LiaoningChina

The Charpy impact properties of 15Cr12MoVWN ferritic/martensitic steel for sodium-cooled reactors with variation in heat treatment factors and parameters are reported.The results show that the ductile-to-brittle transition temperature(DBTT)increased and the upper shelf energy(USE)decreased with increase in normalizing temperature.However,the variation tendency of DBTT and USE was the opposite with increase in tempering temperature.The tempering temperature showed a greater influence on USE than the normalizing temperature,and normalizing and tempering temperatures had the equally significant effects on DBTT,but the cooling method was not a significant factor for DBTT and USE.The prior austenite grain and M_(23)C_(6) size were the main influences on DBTT,and the dislocation density was the main factor affecting the variation of USE.The heat-treatment regime recommended for 15Cr12MoVWN steel was composed of normalizing at 1000-1050℃ for 0.5 h followed by water quenching or air cooling and tempering at 760℃ for 1.5 h.

关键词： 15Cr12MoVWN steel Ductile-to-brittle transition temperature Prior austenite grain size M23C6-MX

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