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Secure resource allocation against colluding eavesdropping in a user-centric cell-free massive multiple-input multiple-output system

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 500-512页

作者： Na LI Yuanyuan GAO Kui XU Xiaochen XIA Huazhi HU yang LI yueyue ZHANG College of Communication Engineering Army Engineering University of PLANanjing 210007China

We investigate the resource allocation problem of a cell-free massive multiple-input multiple-output system under the condition of colluding eavesdropping by multiple passive eavesdroppers.To address the problem of limited pilot resources,a scheme is proposed to allocate the pilot with the minimum pollution to users based on access point selection and optimize the pilot transmission power to improve the accuracy of channel estimation.Aiming at the secure transmission problem under a colluding eavesdropping environment by multiple passive eavesdroppers,based on the local partial zero-forcing precoding scheme,a transmission power optimization scheme is formulated to maximize the system’s minimum security spectral efficiency.Simulation results show that the proposed scheme can effectively reduce channel estimation error and improve system security.

关键词： Cell-free Colluding eavesdropping Limited pilot resources Access point selection Security rate

A sequential continuous flow synthesis and purification process of calcium dibutyryladenosine cyclophosphate

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Chinese Chemical Letters 2024年第2期35卷 402-406页

作者： Liming Cao Maolin Sun Chaoming Liang Lei yang yueyue Ma Ruihua Cheng Yanxiong Ke Wei Yu Jinxing Ye Engineering Research Center of Pharmaceutical Process Chemistry Ministry of EducationSchool of PharmacyEast China University of Science and TechnologyShanghai 200237China School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhou 510006China Shanghai No.1 Biochemical& Pharmaceutical Co. Ltd.Shanghai 200080China

Calcium dibutyryladenosine cyclophosphate is a widely used cardiovascular drug.The traditional batch synthesis process suffers from long reaction times,tedious operations,and unstable yields.Herein,a sequential continuous flow synthesis combined with a multistage in-line purification process of calcium dibutyryladenosine cyclophosphate was developed.The acylation reaction was completed in a continuous coil reactor at 160℃ in 20 min.And the high toxic solvent pyridine was replaced by acetonitrile.Furthermore,the multistage in-line purification process was integrated into the homemade 3D circular cyclone-type micromixer chip.Combining with the membrane phase separators,the residence time of the purification step was 30 s.The isolated yield of this sequential continuous process was 92%with 99%purity.

关键词： Flow chemistry Calcium dibutyryladenosine cyclophosphate Continuous flow synthesis In-line purification 3D circular cyclone-type micromixer chip

Machine learning predicts atomistic structures of multielement solid surfaces for heterogeneous catalysts in variable environments

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The Innovation 2024年第2期5卷 79-87页

作者： Huan Ma yueyue Jiao Wenping Guo Xingchen Liu Yongwang Li Xiaodong Wen State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of Chinese Academy of Sciences Beijing 100049China National Energy Center for Coal to Liquids Synfuels China Co.Ltd.Beijing 101400China Beijing Advanced Innovation Center for Materials Genome Engineering IndustryUniversity Cooperation Base between Beijing Information S&T University and Synfuels China Co.Ltd.Beijing 100101China

Solid surfaces usually reach thermodynamic equilibrium through particle exchange with their environment under reactive conditions.A prerequisite for understanding their functionalities is detailed knowledge of the surface composition and atomistic geometry under working conditions.Owing to the large number of possible Miller indices and terminations involved in multielement solids,extensive sampling of the compositional and conformational space needed for reliable surface energy estimation is beyond the scope of ab initio calculations.Here,we demonstrate,using the case of iron carbides in environments with varied carbon chemical potentials,that the stable surface composition and geometry of multielement solids under reactive conditions,which involve large compositional and conformational spaces,can be predicted at ab initio accuracy using an approach that combines the bond valence model,Gaussian process regression,and ab initio thermodynamics.Determining the atomistic structure of surfaces under working conditions paves the way toward identifying the true active sites of multielement catalysts in heterogeneous catalysis.

关键词： surfaces solids environments

Cooperative Anti-Jamming and Interference Mitigation for UAV Networks: A Local Altruistic Game Approach

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China Communications 2024年第2期21卷 183-196页

作者： yueyue Su Nan Qi Zanqi Huang Rugui Yao Luliang Jia College of Electronic Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China School of Space Information Space Engineering UniversityBeijing 101416China

To improve the anti-jamming and interference mitigation ability of the UAV-aided communication systems, this paper investigates the channel selection optimization problem in face of both internal mutual interference and external malicious jamming. A cooperative anti-jamming and interference mitigation method based on local altruistic is proposed to optimize UAVs’ channel selection. Specifically, a Stackelberg game is modeled to formulate the confrontation relationship between UAVs and the jammer. A local altruistic game is modeled with each UAV considering the utilities of both itself and other UAVs. A distributed cooperative anti-jamming and interference mitigation algorithm is proposed to obtain the Stackelberg equilibrium. Finally, the convergence of the proposed algorithm and the impact of the transmission power on the system loss value are analyzed, and the anti-jamming performance of the proposed algorithm can be improved by around 64% compared with the existing algorithms.

关键词： channel selection cooperative antijamming and interference mitigation local altruistic game Stackelberg game unmanned aerial vehicle(UAV)

Trench gate GaN IGBT with controlled hole injection efficiency

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 10-16页

作者： Huang Yi Li yueyue Gao Sheng Wang Qi Liu Bin Han Genquan School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Electronic Science and Engineering Nanjing UniversityNanjing 210008China School of Microelectronics Xidian UniversityXi’an 710126China

In this paper,a novel trench gate gallium nitride(GaN)insulated gate bipolar transistor(GaN IGBT),in which the collector is divided into multiple regions to control the hole injection efficiency,is designed and theoretically studied.The incorporation of a P+/P-multi-region alternating structure in the collector region mitigates hole injection within the collector region.When the device is in forward conduction,the conductivity modulation effect results in a reduced storage of carriers in the drift region.As a result,the number of carriers requiring extraction during device turn-off is minimized,leading to a faster turn-off speed.The results illustrate that the GaN IGBT with controlled hole injection efficiency(CEH GaN IGBT)exhibits markedly enhanced performance compared to conventional GaN IGBT,showing a remarkable 42.2%reduction in turn-off time and a notable 28.5%decrease in turn-off loss.

关键词： gallium nitride insulated gate bipolar transistor(GaN IGBT) hole injection trench gate turn-off loss

Structural Isomers:Small Change with Big Difference in Anion Storage

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Nano-Micro Letters 2024年第1期16卷 222-234页

作者： Huichao Dai Yuan Chen yueyue Cao Manli Fu Linnan Guan Guoqun Zhang Lei Gong Mi Tang Kun Fan Chengliang Wang School of Integrated Circuits Wuhan National Laboratory for Optoelectronics(WNLO)Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China Wenzhou Advanced Manufacturing Institute Huazhong University of Science and TechnologyWenzhou 325035People’s Republic of China Hubei Key Laboratory of Polymer Materials School of Materials Science and EngineeringHubei UniversityWuhan 430062People’s Republic of China School of Chemistry and Environmental Engineering Wuhan Institute of TechnologyWuhan 430073People’s Republic of China

Organic electrode materials are promising for batteries.However,the reported organic electrodes are often facing the challenges of low specific capacity,low voltage,poor rate capability and vague charge storage mechanisms,etc.Isomers are good platform to investigate the charge storage mechanisms and enhance the performance of batteries,which,however,have not been focused in batteries.Herein,two isomers are reported for batteries.As a result,the isomer tetrathiafulvalene(TTF)could store two monovalent anions reversibly,deriving an average discharge voltage of 1.05 V and a specific capacity of 220 mAh g−1 at a current density of 2 C.On the other hand,the other isomer tetrathianaphthalene could only reversibly store one monovalent anion and upon further oxidation,it would undergo an irreversible solid-state molecular rearrangement to TTF.The molecular rearrangement was confirmed by electrochemical performances,X-ray diffraction patterns,nuclear magnetic resonance spectra,and 1H detected heteronuclear multiple bond correlation spectra.These results suggested the small structural change could lead to a big difference in anion storage,and we hope this work will stimulate more attention to the structural design for boosting the performance of organic batteries.

关键词： Zinc-organic batteries Isomers Solid-state molecular rearrangement Anion storage P-type organic electrode materials

class activation maps;laser-induced damage;semantic segmentation;weakly supervised learning

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High Power Laser Science and Engineering 2024年第1期12卷 30-41页

作者： yueyue Han Yingyan Huang Hangcheng Dong Fengdong Chen Fa Zeng Zhitao Peng Qihua Zhu Guodong Liu School of Instrumentation Science and Engineering Harbin Institute of TechnologyHarbinChina Research Center of Laser Fusion China Academy of Engineering PhysicsMianyangChina

Segmenting dark-field images of laser-induced damage on large-aperture optics in high-power laser facilities is challenged by complicated damage morphology, uneven illumination and stray light interference. Fully supervised semantic segmentation algorithms have achieved state-of-the-art performance but rely on a large number of pixel-level labels, which are time-consuming and labor-consuming to produce. LayerCAM, an advanced weakly supervised semantic segmentation algorithm, can generate pixel-accurate results using only image-level labels, but its scattered and partially underactivated class activation regions degrade segmentation performance. In this paper, we propose a weakly supervised semantic segmentation method, continuous gradient class activation mapping(CAM) and its nonlinear multiscale fusion(continuous gradient fusion CAM). The method redesigns backpropagating gradients and nonlinearly activates multiscale fused heatmaps to generate more fine-grained class activation maps with an appropriate activation degree for different damage site sizes. Experiments on our dataset show that the proposed method can achieve segmentation performance comparable to that of fully supervised algorithms.

关键词： class activation maps laser-induced damage semantic segmentation weakly supervised learning

Two-step continuous flow process of sodium tanshinone ⅡA sulfonate using a 3D circular cyclone-type microreactor

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Chinese Chemical Letters 2024年第1期35卷 290-294页

作者： Maolin Sun Chaoming Liang Liming Cao Yaguo Wang Jiasheng yang Shiyu Hou Wei Yu yueyue Ma Ruihua Cheng Jinxing Ye School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhou 510006China School of Pharmacy East China University of Science and TechnologyShanghai 200237China School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Shanghai No.1 Biochemical&Pharmaceutical Co. Ltd.Shanghai 200080China

A sustainable and practical process is presented for the direct synthesis of sodium tanshinone IIA sulfonate(STS).Our approach was inspired by the well-established and industrially applied batch synthetic route for STS production.We constructed a telescoped two-step continuous flow platform.This involved a continuous tanshinone IIA sulfonation and in-line salt formation.For the setup,we constructed a 3D circular cyclone-type microreactor using femtosecond laser micromachining.Compared to the 68%yield for 2 h in batch,the two-step continuous flow had an STS yield of 90%,achieved for a total residence time of<3.0 min under optimal conditions.The proposed continuous flow method vastly simplified the operation and improved procedural safety,while significantly reducing the required acid content and wastewater production.

关键词： Continuous flow Sodium tanshinone IIA sulfonate Cardiovascular Microreactor Green chemistry

Synergistic effects of chemical additives and mature compost on reducing H_2S emission during kitchen waste composting

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Journal of Environmental Sciences 2024年第5期139卷 84-92页

作者： Yongdi Liu Haihou Wang Hao Zhang yueyue Tao Rui Chen Sheng Hang Xiaoyan Ding Meidi Cheng Guochun Ding Yuquan Wei Ting Xu Ji Li College of Resources and Environmental Science Beijing Key Laboratory of Biodiversity and Organic FarmingChina Agricultural UniversityBeijing 100193China Organic Recycling Institute(Suzhou)of China Agricultural University Wuzhong DistrictSuzhou 215128China Suzhou Academy of Agricultural Sciences Institute of Agricultural Sciences in Taihu Lake DistrictSuzhou 215155China Technical Centre for Soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China College of Chemistry and Chemical Engineering Yantai UniversityYantai 264005China

Additives could improve composting performance and reduce gaseous emission,but few studies have explored the synergistic of additives on H_(2)S emission and compost maturity.This research aims to make an investigation about the effects of chemical additives and mature compost on H_(2)S emission and compost maturity of kitchen waste composting.The results showed that additives increased the germination index value and H_(2)S emission reduction over 15 days and the treatment with both chemical additives and mature compost achieved highest germination index value and H_(2)S emission reduction(85%).Except for the treatment with only chemical additives,the total sulfur content increased during the kitchen waste composting.The proportion of effective sulfur was higher with the addition of chemical additives,compared with other groups.The relative abundance of H_(2)S-formation bacterial(Desulfovibrio)was reduced and the relative abundance of bacterial(Pseudomonas and Paracoccus),which could convert sulfur-containing substances and H_(2)S to sulfate was improved with additives.In the composting process with both chemical additives and mature compost,the relative abundance of Desulfovibrio was lowest,while the relative abundance of Pseudomonas and Paracoccus was highest.Taken together,the chemical additives and mature compost achieved H_(2)S emission reduction by regulating the dynamics of microbial community.

关键词： Kitchen waste composting Sulfur conversion Chemical additives Mature compost Microbial community