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Pure quantum gradient descent algorithm and full quantum variational eigensolver

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Frontiers of physics 2024年第2期19卷 221-234页

作者： Ronghang Chen Zhou Guang Cong Guo Guanru Feng Shi-Yao hou College of Physics and Electronic Engineering Center for Computational SciencesSichuan Normal UniversityChengdu 610068China Shenzhen SpinQ Technology Co. Ltd.Shenzhen 518045China DEEPROUTE.AI

Optimization problems are prevalent in various fields,and the gradient-based gradient descent algorithm is a widely adopted optimization ***,in classical computing,computing the numerical gradient for a function with variables necessitates at least d+1 function evaluations,resulting in a computational complexity of O(d).As the number of variables increases,the classical gradient estimation methods require substantial resources,ultimately surpassing the capabilities of classical ***,leveraging the principles of superposition and entanglement in quantum mechanics,quantum computers can achieve genuine parallel computing,leading to exponential acceleration over classical algorithms in some *** this paper,we propose a novel quantum-based gradient calculation method that requires only a single oracle calculation to obtain the numerical gradient result for a multivariate *** complexity of this algorithm is just O(1).Building upon this approach,we successfully implemented the quantum gradient descent algorithm and applied it to the variational quantum eigensolver(VQE),creating a pure quantum variational optimization *** with classical gradient-based optimization algorithm,this quantum optimization algorithm has remarkable complexity advantages,providing an efficient solution to optimization *** proposed quantum-based method shows promise in enhancing the performance of optimization algorithms,highlighting the potential of quantum computing in this field.

关键词： quantum algorithm gradient descent variational quantum algorithm

Clinical manifestations and the prenatal diagnosis of trisomy 7 mosaicism:Two case reports

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World Journal of Clinical Cases 2024年第8期12卷 1544-1548页

作者： Fei hou Yan Li Hua Jin Department of Prenatal Diagnosis Jinan Maternal and Child Health HospitalJinan 250001Shandong ProvinceChina

BACKGROUND The clinical manifestations of trisomy 7 mosaicism are diverse and nonspecific,so prenatal diagnosis is very *** SUMMARY Two pregnant women with abnormal prenatal screening results were *** was a 22-year-old woman(G1P0).At 31st week of gestation,ultrasound revealed that the posterior horn of the left lateral ventricle was 10 mm and the right renal pelvis had a separation of 7 *** other pregnant woman was 33 years old(G2P1L1A0),and her fetus was found to have a cardiac malformation at the 24th week of *** number variation sequencing,whole-exome sequencing and karyotype analysis were carried out after amniocentesis,and both fetuses were diagnosed with trisomy 7 *** parental counseling,one woman continued the pregnancy,and the other woman terminated the *** In trisomy 7 mosaicism,the low proportion of trisomy does not lead to abortion,but can result in abnormal fetal development,which can be detected via ***,clinicians need to pay more attention to various aspects of fetal growth and development,combining with imaging,cellular,molecular genetics and other methods to perform comprehensive evaluations of fetuses to provide more reliable genetic counseling for pregnant women.

关键词： Trisomy 7 mosaicism Copy number variation sequencing Whole-exome sequencing Karyotype analysis Prenatal diagnosis Case report

Perturbation to Symmetries and Adiabatic Invariants for Generalized Birkhoffian Systems on Time Scales

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Wuhan University Journal of Natural Sciences 2024年第3期29卷 263-272页

作者： hou Shuang SONG Chuanjing School of Mathematical Sciences Suzhou University of Science and TechnologySuzhou 215009JiangsuChina

Time scale is a new and powerful tool for dealing with complex dynamics problems. The main result of this study is the exact invariants and adiabatic invariants of the generalized Birkhoffian system and the constrained Birkhoffian system on time scales. Firstly, we establish the differential equations of motion for the above two systems and give the corresponding Noether symmetries and exact invariants. Then, the perturbation to the Noether symmetries and the adiabatic invariants for the systems mentioned above under the action of slight disturbance are investigated, respectively. Finally, two examples are provided to show the practicality of the findings.

关键词： time scale generalized Birkhoffian system Noether symmetry perturbation and adiabatic invariants

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A 26.5–29.5-GHz Doherty PA with enhanced linearity and efficiency based on adaptive bias circuit for 5G MIMO arrays

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Science China(Information Sciences) 2024年第7期67卷 341-342页

作者： Long WANG Jixin CHEN Debin hou Xiaojie XU Wei HONG State Key Laboratory of Millimeter Waves Southeast University Misic Microelectronics Co. Ltd.

Power amplifiers (PAs) play a crucial role in achieving key performance metrics such as efficiency, power, and ***, in the millimeter-wave frequency range, the performance of active devices rapidly deteriorates with increasing frequency. The typical Doherty architecture, through load modulation techniques, can achieve high back-off efficiency [1]. To enhance the linearity of the PA, adaptive bias circuits (ADBs) have been widely adopted [2, 3].

关键词： POWER-AMPLIFIER

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Reinforcement Learning Navigation for Robots Based on Hippocampus Episode Cognition

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Journal of Bionic Engineering 2024年第1期21卷 288-302页

作者： Jinsheng Yuan Wei Guo Zhiyuan hou Fusheng Zha Mantian Li Pengfei Wang Lining Sun State Key Laboratory of Robotics and System Harbin Institute of Technology(HIT)Harbin 150001China Shenzhen Academy of Aerospace Technology Shenzhen 518057China School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050China

Artificial intelligence is currently achieving impressive success in all ***,autonomous navigation remains a major challenge for *** learning is used for target navigation to simulate the interaction between the brain and the environment at the behavioral level,but the Artificial Neural Network trained by reinforcement learning cannot match the autonomous mobility of humans and *** hippocampus–striatum circuits are considered as key circuits for target navigation planning and *** paper aims to construct a bionic navigation model of reinforcement learning corresponding to the nervous system to improve the autonomous navigation performance of the *** ventral striatum is considered to be the behavioral evaluation region,and the hippocampal–striatum circuit constitutes the position–reward *** this paper,a set of episode cognition and reinforcement learning system simulating the mechanism of hippocampus and ventral striatum is constructed,which is used to provide target guidance for the robot to perform autonomous *** with traditional methods,this system reflects the high efficiency of learning and better Environmental *** research is an exploration of the intersection and fusion of artificial intelligence and neuroscience,which is conducive to the development of artificial intelligence and the understanding of the nervous system.

关键词： Episode cognition Reinforcement learning Hippocampus Robot navigation

不同降雨年型施氮量对延迟收获夏玉米产量、强弱势粒形态与粒重的影响

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中国农业科学 2023年第20期56卷 3975-3995页

作者：刘梦张垚葛均筑杨永安吴锡冬侯海鹏天津市主要农作物智能育种重点实验室/天津农学院农学与资源环境学院西北农林科技大学农学院天津市优质农产品开发示范中心天津市农业发展服务中心

【目的】华北平原热量资源有限，夏播玉米收获期籽粒含水率高，影响机械粒收质量，限制了该项技术在该区域的应用。延迟收获条件下，施氮量差异对夏玉米籽粒产量、强弱势粒形态、粒重等关键产量性状的影响尚不明确。通过对不同施氮水平... 详细信息

【目的】华北平原热量资源有限，夏播玉米收获期籽粒含水率高，影响机械粒收质量，限制了该项技术在该区域的应用。延迟收获条件下，施氮量差异对夏玉米籽粒产量、强弱势粒形态、粒重等关键产量性状的影响尚不明确。通过对不同施氮水平强弱势粒形态、灌浆及脱水过程的系统观测，明确氮肥调控效应，为区域机械粒收夏玉米稳产减氮增效栽培提供支持。【方法】2020—2021年选用粒收夏玉米品种京农科728为材料，采用收获时期和施氮量二因素区组试验设计，收获时期设正常果穗收获(NH)和延迟籽粒收获(DH),6个纯氮施用水平分别为0(N0)、120(N120,2021)、180(N180)、240(N240)、300(N300)、360(N360)和450 kg hm-2(N450,2020)，测定产量(GY)、籽粒鲜体积(GFV)、鲜重(GFW)、干重(GDW)、含水率(GMC)及其变化速率。【结果】与干旱年型(2020年)相比，多雨年型(2021年)弱势粒的GFV、GFW和GDW的最大变化速率(Gmax)、生长量(Wmax)和起始势(R0)显著降低，到达最大变化速率时间(Tmax)推迟，活跃期(P)延长，导致弱势粒的GFV、GFW和GDW显著降低15.4%—50.6%、25.4%—62.0%和31.2%—57.3%，而强势粒不显著，GY显著降低3.03×103—5.44×103kg·hm-2。多雨年型条件下，弱势粒的GDWGmax、GDWWmax和GDWR0比强势粒显著降低55.1%—258.1%、13.4%—143.0%和12.0%—126.6%,GDWTmax推迟4.2—20.7 d，强势粒的GFV、GFW和GDW比弱势粒显著提高56.8%—69.6%、67.0%—80.4%和54.1%—92.1%。与NH相比，延迟收获籽粒的Gmax和R0提高，强、弱势粒的P显著延长；在干旱年型和多雨年型下，GFV、GFW显著降低2.1%—8.1%和12.2%—17.1%、4.0%—5.2%和15.7%—19.5%,GDW自25.1—28.2 g/100 grains提高到28.0—34.4 g/100 grains,GMC降至22.6%—26.0%，降幅达31.3%—40.4%，产量提高0.02×103—1.67×103kg·hm-2。干旱年型施氮水平间的GFV、GFW、GDW无显著差异；多雨年型N240-N360处理的GDWGmax、GDWWmax比N180提高，GDWTmax推迟，GDWP延长，差异均达显著水平，且对弱势粒影响强于强势粒。DH处理下，N240-N360弱势粒的GFV、GFW和GDW比N180显著提高25.7%—85.3%、59.4%—83.6%和17.9%—43.9%。多雨年型下氮肥的增产效应(74.4%—169.5%)显著高于干旱年型(51.5%—99.1%),N240GY比N120-N180显著提高12.6%—54.5%。【结论】华北平原热量资源限制区小麦-玉米种植制度，将冬小麦变为春小麦，夏玉米延迟收获23—33 d，显著提高弱势粒库容与粒重，籽粒含水率降低至籽粒机收含水率标准，实现周年机械化粒收。优化施氮247.2—248.6 kg·hm-2，实现不同降雨年型下产量稳定在7.0×103—12.0×103kg·hm-2的稳产减氮增效的生产目标。

关键词：夏玉米降雨年型延迟收获施氮量强弱势粒籽粒灌浆

Mathematical model and numerical investigation of the influence of spray drying parameters on granule sizes of mold powder

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Particuology 2024年第2期85卷 280-295页

作者： Fei Zhang Youyu Lu Shaoyan Zhu Funian Han Guanghua Wen Ping Tang Zibing hou College of Materials Science and Engineering Chongqing UniversityChongqing400044China Guizhou Academy of Testing and Analysis Guizhou Academy of SciencesGuiyang550014China

In this work,the formation mechanism of the droplet-to-granule was investigated in detail based on mold powder manufacturing.A specific mathematical model of two-stage spray drying was established to describe droplet and granule motion,heat and mass transfer,and granule morphology during spray ***,the relationships between spray drying parameters(inlet temperature,atomization pres-sure,slurry mass flow rate)and the properties of the drying tower(temperature and velocity fields)and mold powder granules(temperature,evaporation rates,moisture content,and diameter)were simulated and calculated using ANSYS/Fluent *** ensure that the granule size of mold powder was controlled within the ideal range(0.2-0.6 mm)for producing granules with appropriate mechanical and metallurgical properties,the following optimum spray drying parameters were chosen based on the results of the numerical simulation:inlet temperatures,873 K;slurry atomization pressure,1.8 MPa;slurry mass flow rate,0.05 kg *** these parameters,the slurry mass flow rate has the most significant effect on granule size.

关键词： Mold powder slurry Spray drying parameters Mathematical model Numerical simulation Granule sizes

Hemostatic mechanism of Jianpi Yiqi Shexue decoction(健脾益气摄血方) in treatment of immune thrombocytopenia

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Journal of Traditional Chinese Medicine 2024年第3期44卷 537-544页

作者： LI Ruibai CHEN Ke MA Wei ZHANG Yayue hou Li CHEN Xinyi Department of Oncology and Hemotology Dongzhimen HospitalBeijing University of Chinese Medicine Department of Hemotology Xiyuan HospitalChina Academy of Chinese Medical Sciences

OBJECTIVE: To explore the early hemostatic mechanism of Jianpi Yiqi Shexue decoction(健脾益气摄血方, JYSD) in treating immune thrombocytopathy(ITP), based on the functional homeostasis of brain-intestine axis and blood neurotransmitter METHODS: Non-drug treatment cases: Healthy volunteers were selected as normal control group and compared with patients with dysfunctional uterine bleeding, gastrointestinal tumors with bleeding and ITP, to detect the changes of blood 5-hydroxytryptamine(5-HT), β-endorphin(β-EP), vasoactive intestinal peptide(VIP) and compare the changes of blood neurotransmitters in patients with different disease symptoms. Drug treatment cases: According to the randomized controlled multicenter clinical trial, 272 ITP patients were randomly divided into three groups: treatment group(JYSD) combined group(JYSD + Prednisone) control group(Prednisone). The changes of blood neurotransmitter(5-HT, β-EP, VIP) before and after treatment were detected on the basis of peripheral blood platelet(PLT) and grade score. RESULTS: Non-drug treatment cases: compared with the normal control group, the 5-HT level was higher, and the VIP and β-EP levels were both lower in the ITP group(P < 0.001), and the 5-HT, VIP and β-EP levels in the Gastrointestinal tumors with bleeding group were also lower compared with the normal control group(P < 0.05, 0.001). Drug treatment cases: The PLT grading scores of the combination group and the control group after treatment were lower than that before treatment(P < 0.05, 0.001). The PLT grading score of the 3 groups were compared in pairs after treatment: the combination group was the lowest among the 3 groups, which was better than the treatment group, but no better than the control group(vs the treatment group, P = 0.005, vs the control group, P = 0.709). The statistical results of full analysis set(FAS) and per protocol set(PPS) were consistent. The bleeding symptom scores of the treatment and combination groups began to drop 7 d after trea

关键词： beta-endorphin brain-gut axis immune thrombocytopenic purpura serotonin vasoactive intestinal peptide

DC Traction Power Supply System Based on Modular Multilevel Converter Suitable for Energy Feeding and De-icing

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 649-659页

作者： Lingxi hou Shuqing Zhang Yingdong Wei Xiaoqian Li Qirong Jiang Mingrui Li Weirui Li Department of Electrical Engineering Tsinghua UniversityBeijing 100084China

A novel DC traction power supply system suitable for energy feeding and de-icing is proposed in this paper for an urban rail transit catenary on the basis of the full bridge submodule (FBSM) modular multilevel converter (MMC). The FBSM-MMC is a novel type of voltage source converter (VSC) and can directly control the output DC voltage and conduct bipolar currents, thus flexibly controlling the power flow of the urban rail transit catenary. The proposed topology can overcome the inherent disadvantages of the output voltage drop in the diode rectifier units, increase the power supply distance and reduce the number of traction substations. The flexible DC technology can coordinate multiple FBSM-MMCs in a wide area and jointly complete the bidirectional control of catenary power flow during the operation of the electric locomotive, so as to realize the local consumption and optimal utilization of the recovered braking energy of the train. In addition, the FBSM-MMCs can also adjust the output current when the locomotive is out of service to prevent the catenary from icing in winter. The working modes of the proposed topology are illustrated in detail and the control strategy is specially designed for normal locomotive operations and catenary de-icing. Simulation cases conducted by PSCAD/EMTDC validate the proposed topology and its control strategy.

关键词： DC traction power supply system de-icing for catenary energy feeding modular multilevel converter based on full-bridge submodules(FBSM-MMC) urban rail transit