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Aperture shape optimization in intensity-modulated radiation therapy planning

Nuclear Science and Techniques 2023年第9期34卷 106-117页

作者： Li-Yuan Zhang zhi-guo gui Peng-Cheng Zhang Jie Yang Shanxi Provincial Key Laboratory for Biomedical Imaging and Big Data North University of ChinaTaiyuan 030051China School of Medicine Management Shanxi University of Chinese MedicineTaiyuan 030619China

The gradient element of the aperture gradient map is utilized directly to generate the aperture shape without *** process can be likened to choosing the direction of negative gradient descent for the generic aperture shape *** negative gradient descent direction is more suitable under local conditions and has a slow convergence *** overcome these limitations,this study introduced conjugate gradients into aperture shape optimization based on gradient ***,the aperture gradient map of the current beam was obtained for the proposed aperture shape optimiza-tion method,and the gradients of the aperture gradient map were modulated using conjugate gradients to form a modulated gradient *** aperture shape was generated based on the modulated gradient *** proposed optimization method does not change the optimal solution of the original optimization problem,but changes the iterative search direction when generating the aperture *** performance of the proposed method was verified using cases of head and neck cancer,and prostate *** optimization results indicate that the proposed optimization method better protects the organs at risk and rapidly reduces the objective function value by ensuring a similar dose distribution to the planning target *** to the contrasting methods,the normal tissue complication probability obtained by the proposed optimization method decreased by up to 4.61%,and the optimization time of the proposed method decreased by 5.26%on average for ten cancer *** effectiveness and acceleration of the proposed method were verified through comparative *** to the comparative experiments,the results indicate that the proposed optimization method is more suitable for clinical *** is feasible for the aperture shape optimization involving the proposed method.

关键词： Aperture shape Column generation Conjugate gradient Gradient modulation Direct aperture optimization

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Hard-core Hall tube in superconducting circuits

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Chinese Physics B 2022年第8期31卷 226-233页

作者： Xin Guan Gang Chen Jing Pan zhi-guo gui Department of Materials and Chemical Engineering Taiyuan UniversityTaiyuan 030032China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Light Manipulations and Applications Shandong Normal UniversityJinan 250358China

The Hall tube as a minimum model to simulate the integer quantum Hall effect is essential for exploring topological physics, while it has not been constructed in the recent developing successfully experiments on superconducting *** this work, we propose a feasible experiment scheme using three legs superconducting circuits with transmon qubits to realize a Hall tube. Then we first investigate its topological properties. Since the time–reversal, particle–hole, and chiral symmetries are all broken for the system, the Hall tube belongs to the A class of the Altland–Zirnbauer *** obtain the corresponding topological phase transition both numerically and analytically. Since the chirality is a key character of the quantum Hall effect, we secondly investigate the chiral physics in the Hall tube. We find the topological protected chiral edge currents and discuss its robustness. Finally, we give the possible experimental observations of the topological state and topological protected chiral edge currents.

关键词： Hall tube superconducting circuits topological phase transition chiral edge currents

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Arsenic Trioxide Induces Apoptosis of Glucocorticoid-Resistant Acute Lymphoblastic Leukemia CEM-C1 Cells

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Chinese Journal of Cancer Research 2009年第3期21卷 217-223页

作者： Jiao Ge Xia guo zhi-gui Ma Ling Gu Qiang Li Department of Pediatric Hematology and Immunology West China Second Hospital Sichuan University Chengdu 610041 China

Objective： To explore the effects of arsenic trioxide （ATO） on the apoptosis of glucocorticoid （GC）-resistant T-acute lymphoblastic leukemia （ALL） CEM-C1 cells and its possible mechanisms. Methods： Different concentrations of ATO （0.25 μmol/L-5 μmol/L） were used to induce the apoptosis of CEM-C1 cells. The inhibition rate of cell proliferation and apoptosis were detected by MTT test, Annexin V-FITC/PI flow cytometry and optical microscopy, respectively. RT-PCR was applied to semi-quantitatively analyze the mRNA expression of pro-apoptotic proteins （Bad and PDCD4） and anti-apoptotic proteins （XIAP and MCL-1） induced by different concentrations of ATO at different time points. Results： ATO could inhibit proliferation and induce apoptosis of CEM-C1 cells at a concentration and time dependent manner. Low-dose ATO mildly inhibited the proliferation of CEM-C1 cells while higher concentrations （1 μmol/L and 5 μmol/L） had strong anti-tumor effect with the inhibiting rates of 40.07±7.98% and 88.67±2.88%, respectively. Annexin V-FITC/PI flow cytometry showed that the apoptotic rates of CEM-C1 ceils were significantly increased after 48 hours treatment of different concentrations of ATO. RT-PCR demonstrated up-regulated mRNA expression of pro-apoptotic protein Bad and PDCD4 but down-regulated mRNA expression of anti-apoptotic protein XIAP when CEM-C1 cells were treated with different concentrations of ATO at different time points. The MCL-1 mRNA expression was down-regulated only after the treatment of 5 μmol/L ATO. Conclusion： ATO can inhibit cell proliferation and induce cell apoptosis in GC-resistant CEM-C1 cells. The molecular mechanisms might involve the increased mRNA expression of pro-apoptotic protein Bad and PDCD-4, and rapid down-regulation of XIAP mRNA expression.

关键词： Acute lymphoblastic leukemia CEM-C1 cells Apoptosis arsenic trioxide (ATO)

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Traffic safety helmet wear detection based on improved YOLOv5 network

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Optoelectronics Letters 2025年第1期21卷 35-42页

作者： gui Dongdong SUN Bo College of Software Southeast University Quanzhou Equipment Research Centre Haixi Institute Chinese Academy of Sciences

Aiming at the problem that the current traffic safety helmet detection model can't balance the accuracy of detection with the size of the model and the poor generalization of the model, a method based on improving you only look once version 5(YOLOv5) is proposed. By incorporating the lightweight Ghost Net module into the YOLOv5 backbone network, we effectively reduce the model size. The addition of the receptive fields block(RFB) module enhances feature extraction and improves the feature acquisition capability of the lightweight model. Subsequently, the high-performance lightweight convolution, GSConv, is integrated into the neck structure for further model size compression. Moreover, the baseline model's loss function is substituted with efficient insertion over union(EIoU), accelerating network convergence and enhancing detection precision. Experimental results corroborate the effectiveness of this improved algorithm in real-world traffic scenarios.

关键词： Traffic control

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Offload Strategy for Edge Computing in Satellite Networks Based on Software Defined Network

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Computers, Materials & Continua 2025年第1期82卷 863-879页

作者： zhiguo Liu Yuqing gui Lin Wang Yingru Jiang Communication and Network Laboratory Dalian UniversityDalian116622China College of Environment and Chemical Engineering Dalian UniversityDalian116622China

Satellite edge computing has garnered significant attention from researchers;however,processing a large volume of tasks within multi-node satellite networks still poses considerable *** sharp increase in user demand for latency-sensitive tasks has inevitably led to offloading bottlenecks and insufficient computational capacity on individual satellite edge servers,making it necessary to implement effective task offloading scheduling to enhance user *** this paper,we propose a priority-based task scheduling strategy based on a Software-Defined Network(SDN)framework for satellite-terrestrial integrated networks,which clarifies the execution order of tasks based on their ***,we apply a Dueling-Double Deep Q-Network(DDQN)algorithm enhanced with prioritized experience replay to derive a computation offloading strategy,improving the experience replay mechanism within the Dueling-DDQN ***,we utilize the Deep Deterministic Policy Gradient(DDPG)algorithm to determine the optimal resource allocation strategy to reduce the processing latency of *** results demonstrate that the proposed d3-DDPG algorithm outperforms other approaches,effectively reducing task processing latency and thus improving user experience and system efficiency.

关键词： Satellite network edge computing task scheduling computing offloading

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海洋平台UPS选型计算研究

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海洋工程装备与技术 2015年第3期2卷 201-204页

作者：郭治贵姚小华上海利策科技股份有限公司上海200233

不间断电源(UPS)是海洋石油平台供电系统的重要设备,在正常电源及应急电源失效后,满足通信、仪表控制、电气保护、关键机械设备的控制盘或工作站等重要负荷的供电要求。论述了UPS选型计算方法,并以某海洋石油平台UPS选型为例,进行了工... 详细信息

不间断电源(UPS)是海洋石油平台供电系统的重要设备,在正常电源及应急电源失效后,满足通信、仪表控制、电气保护、关键机械设备的控制盘或工作站等重要负荷的供电要求。论述了UPS选型计算方法,并以某海洋石油平台UPS选型为例,进行了工程计算。所提出的计算方法简便易行,可用于海洋石油平台的电气设计。

关键词：海洋平台供电系统不间断电源重要负荷选型计算

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Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第1期68卷 152-156页

作者： Lihua Zhang Lingjing Chen Huatian Shi Yue Wei gui Chen Tai-Chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology Department of Chemistry and Institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （HCOO-）.Turnover number （TON） for HCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole （BIH） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NHBF4also produced HCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO2reduction.

关键词： photocatalysis noble metal-free CO2 reduction formate cobalt hydride

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生产管理策略转变对荒漠草原家庭牧场草地植被特征的影响

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中国草地学报 2017年第1期39卷 105-110页

作者：李治国张富贵姚蒙韩国栋李江文王瑞珍内蒙古农业大学草原与资源环境学院内蒙古呼和浩特010019 四子王旗草原工作站内蒙古011800 内蒙古自治区草原工作站内蒙古呼和浩特010020

通过对荒漠草原区不同生产管理模式下家庭牧场草地植物特征的测定,分析探讨生产管理策略转变对牧场植被特征的影响。结果表明:荒漠草原家庭牧场草地生产力随降水量的变化而变化,生产管理策略转变后,在短期内对草地生产力影响较小,但长... 详细信息

通过对荒漠草原区不同生产管理模式下家庭牧场草地植物特征的测定,分析探讨生产管理策略转变对牧场植被特征的影响。结果表明:荒漠草原家庭牧场草地生产力随降水量的变化而变化,生产管理策略转变后,在短期内对草地生产力影响较小,但长期实施有助于植物群落中建群种和优势种的恢复,主要表现为植物高度、密度、盖度和多年生丛生禾草种类增加,一二年生植物和多年生杂类草显著减少,根茎禾草的重要值显著提高。

关键词：荒漠草原家庭牧场管理策略植被特征

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Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao Yu-gui Peng Peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

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Cooperative output regulation of heterogeneous directed multi-agent systems: a fully distributed model-free reinforcement learning framework

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Science China(Information Sciences) 2025年

作者： Xiongtao SHI Yanjie LI Chenglong DU Huiping LI Chaoyang CHEN Weihua gui Guangdong Key Laboratory of Intelligent Morphing Mechanisms and Adaptive Robotics School of Mechanical Engineering and Automation Harbin Institute of Technology (Shenzhen) School of Automation Central South University School of Marine Science and Technology Northwestern Polytechnical University School of Information and Electrical Engineering Hunan University of Science and Technology

In this paper, the cooperative output regulation (COR) problem of a class of unknown heterogeneous multi-agent systems (MASs) with directed graphs is studied via a model-free reinforcement learning (RL) based fully distributed eventtriggered control (ETC) strategy. First, we consider the scenario that the exosystem is accessible globally to all agents, an internal model-based augmented algebraic Riccati equation (AARE) is constructed, and its solution is learned by the proposed model-free RL algorithm via online input-output data. Further, for the scenario that the exosystem is accessible only to its adjacent followers, the distributed observers are designed for each agent to get the state of the exosystem, and an internal modelbased fully distributed adaptive ETC protocol is then synthesized to construct the corresponding AARE, and the feedback gain matrix is learned in a model-free fashion. The model-free RL-based control protocol proposed in this paper can not only remove the prior knowledge of agents’ dynamics, but also release the dependence on global information by the adaptive event-triggered mechanism (ETM) and the new graph-based Lyapunov function. Finally, simulation results are illustrated to show the feasibility and effectiveness of the proposed control scheme.

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