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关键词： 成果导向教育   分析化学   教学目标   教学内容   实施策略  

摘要： 成果导向教育能够进一步提高教学的质量,增强学生的就业竞争力和综合实力。文章以分析化学课程教学为例,深入探讨了成果导向教育理念在分析化学课程中的应用,明确基于该理念的课程教学目标设定和教学内容选择,并提出以学生为中心调整教学模式、不断创新教学方法、多元化评价为手段促进持续反馈等教学实施策略,以期促进分析化学教学质量的提升,为社会培养更多符合时代需求的专业人才。

关键词： 通感一体化   无人机   隐蔽通信   干扰选择  

摘要： 无人机隐蔽通信在实现可持续低空经济方面引起了相当大的关注。本文基于通感一体化框架，研究了多无人机协作隐蔽通信网络的系统策略和资源分配，其中多个无人机进行协作感知并在移动监管者(Willie)存在的情况下同时向多个地面用户(GUs)隐蔽传输下行信息。为了提高通信隐蔽性，无人机在干扰(JUAV)模式和信息(IUAV)模式之间自适应切换。为了应对Willie的移动性，采用基于无迹卡尔曼滤波的方法，利用从ISAC回波中提取的时延和多普勒频移来预测和跟踪Willie的位置。通过联合优化JUAV选择策略、IUAV-GU调度、通信/干扰功率分配，本文提出了一个实时公平性传输最大化问题。采用交替优化方法，将原始问题分解为一系列子问题，从而获得有效的次优解。仿真结果表明，所提出的方案能够准确跟踪Willie并有效保证下行隐蔽传输。

关键词： Brain function   Child   Resting state functional magnetic resonance imaging   Tourette syndrome  

摘要： This study investigated the characteristic changes of brain function in children with Tourette syndrome (TS) based on resting-state functional MRI (rs-fMRI) and their correlation with the Yale Global Tic Severity Scale (YGTSS) scores. A total of 19 children diagnosed as TS at the Department of Pediatrics in China-Japan Friendship Hospital from October 2021 to April 2023 were enrolled prospectively as the TS group, and 20 healthy children matched for age and gender were field recruited from the community as the control group. All participants underwent head rs-fMRI scans, and regional homogeneity (ReHo) and amplitude of low-frequency fluctuations (ALFF) values were calculated. YGTSS scores were assessed for the TS group. Pearson correlation analysis and Spearman correlation analysis were used to evaluate the correlation between ReHo, ALFF and YGTSS scores. Receiver operating characteristic (ROC) curves were plotted and area under the curve (AUC) was calculated to evaluate the efficacy of brain function parameters related to YGTSS score in diagnosing TS. The TS group included 19 patients, and aged (8.5±2.6) years, including 13 males (68.4%). The control group included 20 children, and aged (5.5±1.8) years, including 7 males (35.0%). In the TS group, the ReHo values in the left lentiform nucleus gray matter, left occipital lobe fusiform gyrus, right occipital lobe medial gyrus, and right frontal lobe paracentral lobule white matter were lower than those in the control group. The ReHo values in the pons and right cerebellar tonsil region, as well as the ALFF values in the right lingual gyrus, were higher than those in the control group (all P<0.01). The ReHo values in the right frontal lobe paracentral lobule, right occipital lobe medial gyrus, and left occipital lobe fusiform gyrus were positively correlated with vocal frequency (r=0.466, 0.576, 0.491) and intensity (r=0.498, 0.593, 0.609);the ReHo values in the right occipital lobe medial gyruss (r=0.615) and left occ

关键词： 物理层密钥生成   毫米波MIMO   智能超表面   原子最小化  

摘要： 针对毫米波大规模多输入多输出(MIMO)系统中智能超表面(RIS)辅助的密钥生成方法面临的导频开销高、信道信息估计误差大和信道稀疏度依赖性强问题，该文提出一种基于原子范数最小化(ANM)的RIS辅助密钥生成方案。现有基于压缩感知(CS)的密钥生成方案需预设信道稀疏度作为先验知识，且受限于网格化离散建模，易导致密钥失配问题。该方案通过引入ANM技术，将基站(Base Station, BS)与用户(UE)间的级联信道估计问题转化为无限分辨率的稀疏信号恢复问题，结合多信号分类(MUSIC)算法联合估计虚拟离开角(AoDs)与到达角(AoAs)，突破传统网格化约束并消除对稀疏度的显式假设，从而提取高精度信道参数作为密钥源。仿真结果表明，与基于传统CS的方案相比，该方案在5dB的信噪比条件下密钥不一致率降低了47.7%，同时显著减少了导频开销;随着天线规模扩大，其性能优势进一步凸显。该方案为RIS辅助毫米波MIMO系统的密钥生成提供了一种无需先验稀疏度、抗网格误差的可靠解决思路。