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Deep Learning-Based LecturePosture Evaluation

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Wuhan University Journal of Natural Sciences 2024年第4期29卷 315-322页

作者： YANG Yifan ZHANG Tao li weiyu Key Laboratory of Multidisciplinary Management and Control of Complex Systems of Anhui Higher Education Institutes Anhui University of TechnologyMaanshan 243002AnhuiChina School of Microelectronics and Data Science Anhui University of TechnologyMaanshan 243032AnhuiChina

Computer vision,a scientific discipline enables machines to perceive visual information,aims to supplant human eyes in tasksencompassing object recognition,localization,and *** traditional educational settings,instructors or evaluators evaluate teachingperformance based on subjective ***,with the continuous advancements in computer vision technology,it becomes increasinglycrucial for computers to take on the role of judges in obtaining vital information and making unbiased *** thisbackdrop,this paper proposes a deep learning-based approach for evaluating lecture ***,feature information is extracted fromvarious dimensions,including head position,hand gestures,and body posture,using a human pose estimation ***,a machinelearning-based regression model is employed to predict machine scores by comparing the extracted features with expert-assigned *** correlation between machine scores and human scores is investigated through experiment and analysis,revealing a robustoverall correlation(0.6420)between predicted machine scores and human *** ideal scoring conditions(100 points),approximately51.72%of predicted machine scores exhibited deviations within a range of 10 points,while around 81.87%displayed deviationswithin a range of 20 points;only a minimal percentage of 0.12%demonstrated deviations exceeding the threshold of 50 ***,tofurther optimize performance,additional features related to bodily movements are extracted by introducing facial expression recognitionand gesture recognition *** fusion of multiple models resulted in an overall average correlation improvement of 0.0226.

关键词： deep learning human pose estimation object detection correlation

基于人工智能的计算机网络安全维护系统设计策略

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鞋类工艺与设计 2024年第15期4卷 157-159页

作者：李维宇河南轻工职业学院河南郑州450000

步入新时代后,计算机网络的快速发展促进了各地信息高度共享,为人们的工作与生活提供了极大便利,但也伴随着各种各样的网络安全问题。以往网络安全维护大多采取漏洞扫描、防火墙等方法,具有一定的局限性,很难为计算机网络提供全方位的... 详细信息

步入新时代后,计算机网络的快速发展促进了各地信息高度共享,为人们的工作与生活提供了极大便利,但也伴随着各种各样的网络安全问题。以往网络安全维护大多采取漏洞扫描、防火墙等方法,具有一定的局限性,很难为计算机网络提供全方位的安全防护。人工智能技术快速发展的大趋势下,如何充分利用人工智能技术来加强计算机网络安全维护系统设计,是当下需要重点研究的内容。基于此,本文通过对人工智能在计算机网络安全维护系统设计中的应用意义进行探讨,并提出基于人工智能的计算机网络安全维护系统设计策略。

关键词：人工智能计算机网络安全维护系统设计

考虑不可测T接负荷的配电网虚拟三端电流差动保护

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电力系统保护与控制 2024年第15期52卷 81-90页

作者：梁伟宸王泽众周成瀚王亚娟李维宇邹贵彬国网冀北电力有限公司电力科学研究院北京100045 国网冀北电力有限公司北京100054 山东大学电气工程学院山东济南250061

采用电流差动保护可解决高比例分布式电源接入配电网引起的馈线保护问题。然而当馈线内存在不可测T接负荷分支时,差动保护只能利用被保护线路两端的数据构造判据,性能受到影响。为解决该问题,首先分析了不可测T接负荷对传统两端电流差... 详细信息

采用电流差动保护可解决高比例分布式电源接入配电网引起的馈线保护问题。然而当馈线内存在不可测T接负荷分支时,差动保护只能利用被保护线路两端的数据构造判据,性能受到影响。为解决该问题,首先分析了不可测T接负荷对传统两端电流差动保护的影响。在此基础上,提出了一种虚拟三端电流差动保护方法。该方法将被保护线路内部的不可测T接分支等效为一个虚拟支路,利用故障前后线路两端的电压、电流数据估算该虚拟支路的电流相量,并与馈线两端的电流相量一起构成三端电流差动保护判据。仿真结果表明,该方法在无需T接负荷测量数据的前提下能够满足配电网在不同场景下的保护需求,相比传统的电流差动保护具有更高的可靠性与灵敏性。

关键词：电流差动保护配电网不可测T接负荷虚拟支路分布式电源

维普期刊数据库博看期刊

反复胚胎种植失败行PGT-A妇女的临床特点分析

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实用妇科内分泌电子杂志 2024年第8期11卷 7-9页

作者：李为玉周欣段金良中国人民解放军联勤保障部队第九二四医院生殖中心广西桂林541002

目的分析反复胚胎种植失败妇女行植入前遗传学筛查(PGT-A)技术的临床特点。方法选取498例体外受精-胚胎移植治疗的不孕症妇女,其中反复种植失败(RIF)行PGT-A妇女79例(RIF组),对照组419例。根据是否获得整倍体胚胎将79例RIF患者分为获得... 详细信息

目的分析反复胚胎种植失败妇女行植入前遗传学筛查(PGT-A)技术的临床特点。方法选取498例体外受精-胚胎移植治疗的不孕症妇女,其中反复种植失败(RIF)行PGT-A妇女79例(RIF组),对照组419例。根据是否获得整倍体胚胎将79例RIF患者分为获得整倍体胚胎组51例(RIF-S)和未获得组28例(RIF-F)。观察其临床特点。结果RIF组年龄大于对照组,基础卵泡刺激素(FSH)、促黄体生成素(LH)、雌二醇(E_(2))水平均高于对照组,基础窦卵泡计数(AFC)少于对照组,外源性促性腺激素(Gn)用量、人绒毛膜促性腺激素(HCG)日E2水平、获卵数、MII卵数、2PN数均低于对照组(P<0.05)。RIF-S组年龄小于RIF-F组,活检胚胎数、D3优胚数、囊胚数、优囊数均多于RIF-F组(P<0.05)。结论高龄及卵巢储备功能差的女性容易发生RIF。

关键词：反复胚胎种植失败胚胎植入前遗传学筛查胚胎非整倍性

Variations regularity of microorganisms and corrosion of cast iron in water distribution system

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Journal of Environmental Sciences 2018年第12期30卷 177-185页

作者： Wei Qiu weiyu li Junguo He Hongyu Zhao Xiuming liu Yixing Yuan State Key Laboratory of Urban Water Resource and Environment School of Environment Harbin Institute of Technology Harbin Veterinary Research Institute Chinese Academy of Agricultural Sciences School of Architecture and Planning Jilin Jianzhu University School of Foreign Languages Harbin University of Science and Technology

Corrosion, one of the most common problems of metal pipe for water supply, generally leads to poor water quality, bacteria proliferation, water capacity decrease and other problems. As microorganisms affect corrosion by changing the characteristics of metal surface, the mechanism of microbial corrosion still remains unclear. The corrosion behavior of ductile cast iron is implemented in the dynamic flow and static conditions, in which variations of water quality and microbial community are analyzed in details. The results show that if the corrosion rate of ductile cast iron decreases, the corrosion of cast iron will result in a lower DO and a higher total iron in bulk water. The number of microorganisms is not a decisive factor of corrosion, even though the counts of bacteria had a close relationship with DO. On the basis of the detection of the 10 kinds of nitratereducing bacteria by Miseq sequencing, NRB of the biofilm biomass accounts for 18.3% on the 30 th day and 20.5% on the 55 th day. Even though aerobic NRBs go into the biofilm later than the facultative anaerobic NRBs, the growth of the anaerobic NRBs is not affected.

关键词： Water distribution system Ductile cast iron pipe Miseq sequencing

The Fluorination of Boron-Doped Graphene for CF_(x) Cathode with Ultrahigh Energy Density

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Energy & Environmental Materials 2023年第4期6卷 49-57页

作者： Kai Wang Yiyu Feng lingchen Kong Cong Peng Yuanhang Hu weiyu li Yu li Wei Feng School of Material Science and Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Advanced Ceramics and Machining Technology Ministry of EducationTianjin 300072China Institute of Advanced Technology and Equipment Beijing University of Chemical TechnologyBeijing 100029China

The enhancement of the fluorination degree of carbon fluorides(CF_(x))compounds is the most effective method to improve the energy densities of li/CF_(x)batteries because the specific capacity of CF_(x)is proportional to the molar ratio of F to C atoms(F/C).In this study,B-doped graphene(BG)is prepared by using boric acid as the doping source and then the prepared BG is utilized as the starting material for the preparation of CF_(x).The B-doping enhances the F/C ratio of CF_(x)without hindering the electrochemical activity of the C–F *** the fluorination process,B-containing functional groups are removed from the graphene *** facilitates the formation of a defect-rich graphene matrix,which not only enhances the F/C ratio due to abundant perfluorinated groups at the defective edges but also serves as the active site for extra li+*** prepared CF_(x)exhibits the maximum specific capacity of 1204 mAh g^(−1),which is 39.2%higher than that of CF_(x)obtained directly from graphene oxide(without B-doping).An unprecedented energy density of 2974 Wh kg^(−1)is achieved for the asprepared CF_(x)samples,which is significantly higher than the theoretically calculated energy density of commercially available fluorinated graphite(2180 Wh kg^(−1)).Therefore,this study demonstrates a great potential of B-doping to realize the ultrahigh energy density of CF_(x)cathodes for practical applications.

关键词： boron doping energy density fluorinated graphene lithium primary battery rate capability

华南典型稀土元素高丰度区土壤Ce和La的富集原因及环境风险评价

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地球化学 2024年第1期53卷 102-109页

作者：林龙勇程胜王俊李韦钰张晓露黄灶泉李朝晖邓一荣广东省环境科学研究院广东省污染场地环境管理与修复重点实验室/粤港澳环境质量协同创新联合实验室/广东省地球关键带(土壤)污染归趋与风险防控实验室广东广州510045

华南地区离子型稀土资源较为丰富,但地质背景高和稀土无序开采可能会导致部分区域出现土壤稀土元素含量大幅升高,对当地生态环境和人体健康造成威胁。本文以广东省北部某典型稀土元素高丰度区为研究对象,对土壤中Ce和La的富集原因进行... 详细信息

华南地区离子型稀土资源较为丰富,但地质背景高和稀土无序开采可能会导致部分区域出现土壤稀土元素含量大幅升高,对当地生态环境和人体健康造成威胁。本文以广东省北部某典型稀土元素高丰度区为研究对象,对土壤中Ce和La的富集原因进行初步分析,并采用污染负荷指数、潜在生态风险指数等方法评价其环境风险。结果表明,研究区西部区域浅层土壤Ce和La含量最高,均值分别约为170μg/g和89.9μg/g,远高于广东和全国土壤背景值。地质背景高是土壤Ce和La元素高丰度分布的首要因素,稀土无序开采是西部高丰度区土壤Ce和La元素含量进一步升高的重要原因。西部区域土壤的Ce和La元素的污染负荷指数为1.97和2.10,分别属于轻度污染和中度污染水平。研究区土壤Ce和La的潜在生态风险指数分别约为0.37~3.79和0.18~6.15,远小于20,表明单一Ce和La元素对于当地的生态风险较小。研究结果可为我国华南离子型稀土元素高丰度区的土壤污染成因分析和综合整治提供借鉴。

关键词：土壤 Ce La 富集机制环境风险评价

溶胶型纳米SiO_(2)和减水剂对粉煤灰-矿渣地聚物性能的影响

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市政技术 2024年第2期42卷 21-26,114页

作者：李新宇彭金财段立伟王武李伟宇许福湖南省西湖建筑集团有限公司湖南长沙410000 湘潭大学土木工程学院湖南湘潭411105 岳阳路桥集团有限公司湖南岳阳414000

地聚物是一种有望替代普通硅酸盐水泥以降低土木工程行业碳排放的新型绿色环保胶凝材料。然而,粉煤灰-矿渣地聚物存在流动性差、干燥收缩大等问题,限制了其在工程领域的进一步推广应用。因此,通过试验研究了复掺减水剂和溶胶型纳米SiO_... 详细信息

地聚物是一种有望替代普通硅酸盐水泥以降低土木工程行业碳排放的新型绿色环保胶凝材料。然而,粉煤灰-矿渣地聚物存在流动性差、干燥收缩大等问题,限制了其在工程领域的进一步推广应用。因此,通过试验研究了复掺减水剂和溶胶型纳米SiO_(2)对粉煤灰-矿渣地聚物工作性能、干燥收缩和抗压强度的影响,并分析了相关机理。试验结果表明,对于粉煤灰-矿渣质量比为7∶3的体系,与未掺加溶胶型纳米SiO_(2)和减水剂的粉煤灰-矿渣地聚物相比,当溶胶型纳米SiO_(2)和减水剂掺量分别为0.2%和1.0%时,粉煤灰-矿渣地聚物流动度从176 mm增大至198 mm,27 d干燥收缩降低了31.2%,3、7、28 d抗压强度分别提高了52.2%、24.5%、32.3%;溶胶型纳米SiO_(2)和减水剂复掺增加了参与反应的活性硅源,形成了更多的N-A-S-H和C-(A)-S-H凝胶产物,使得硬化后材料的结构更加致密。该研究可为粉煤灰-矿渣地聚物的进一步研究和应用提供参考。

关键词：地聚物纳米SiO_(2) 减水剂干燥收缩抗压强度

SPDEF suppresses head and neck squamous cell carcinoma progression by transcriptionally activating NR4A1

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International Journal of Oral Science 2021年第4期13卷 370-380页

作者： Yanting Wang Xianyue Ren weiyu li Ruoyan Cao Suyang liu Laibo Jiang Bin Cheng Juan Xia Hospital of Stomatology Sun Yat-sen UniversityGuangzhouChina Guangdong Provincial Key Laboratory of Stomatology GuangzhouChina Guanghua School of Stomatology Sun Yat-sen UniversityGuangzhouChina

SAM pointed domain containing E26 transformation-specific transcription factor(SPDEF)plays dual roles in the initiation and development of human ***,the biological role of SPDEF in head and neck squamous cell carcinoma(HNSCC)remains *** this study,the expression level of SPDEF and its correlation with the clinical parameters of patients with HNSCC were determined using TCGA-HNSC,GSE65858,and our own clinical ***8,colony formation,cell cycle analysis,and a xenograft tumor growth model were used to determine the molecular functions of SPDEF in ***-qPCR,dual luciferase reporter assay,and rescue experiments were conducted to explore the potential molecular mechanism of SPDEF in *** with normal epithelial tissues,SPDEF was significantly downregulated in HNSCC *** with HNSCC with low SPDEF mRNA levels exhibited poor clinical *** SPDEF inhibited HNSCC cell viability and colony formation and induced G0/G1 cell cycle arrest,while silencing SPDEF promoted cell proliferation in *** xenograft tumor growth model showed that tumors with SPDEF overexpression had slower growth rates,smaller volumes,and lower *** could directly bind to the promoter region of NR4A1 and promoted its transcription,inducing the suppression of AKT,MAPK,and NF-κB signaling ***,silencing NR4A1 blocked the suppressive effect of SPDEF in HNSCC ***,we demonstrate that SPDEF acts as a tumor suppressor by transcriptionally activating NR4A1 in *** findings provide novel insights into the molecular mechanism of SPDEF in tumorigenesis and a novel potential therapeutic target for HNSCC.

关键词： inhibited SPD NR4A1