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关键词： 股骨颈骨折   半髋关节置换   人工股骨头置换   多因素分析   预测模型   列线图   骨科植入物  

摘要： 背景:人工股骨头置换是老年人股骨颈骨折最主要的手术方式之一,然而术后髋关节功能不良是一个常见且棘手的问题。目的:建立老年股骨颈骨折患者行人工股骨头置换后早期髋关节功能改善情况的列线图预测模型并进行验证。方法:回顾性选择2022年1月至2023年10月在喀什地区第一人民医院因股骨颈骨折行人工股骨头置换的230例患者,收集可能影响术后早期髋关节功能的相关因素,在术后6个月时采用Harris髋关节评分量表评估髋关节功能改善情况。根据术后髋关节功能改善情况是否理想将患者分为功能正常组和功能不良组,比较两组患者术前、术中及术后因素,以LASSO回归筛选潜在因素后行多因素Logistic回归,以R4.1.3软件建立列线图预测模型并进行内部验证。结果与结论:①最终纳入221例患者,术后6个月患者平均Harris评分为82.07±8.28;②LASSO回归筛选出4个潜在影响因素,以此行多因素logistic回归分析结果显示,年龄、体质量指数、受伤至手术天数及术后负重时间为术后早期髋关节功能不良的独立影响因素(P<0.05);③根据多因素结果建立列线图模型,校准曲线结果显示,预测曲线与标准曲线基本拟合;受试者操作特征曲线分析结果显示,列线图模型预测术后早期髋关节功能不良的曲线下面积为0.870[95%CI(0.819,0.921)];④术后早期髋关节功能改善情况受年龄、体质量指数、受伤至手术天数及术后负重时间等因素的影响,此次研究建立的列线图模型用于预测人工股骨头置换后早期髋关节功能不良具有较高的区分度与准确度。

关键词： Piping systems   Sound field prediction   Dipole arrays   Modal expansion method for irregular enclosures   Acoustical optimization  

摘要： The sound field driven by piping systems in enclosures may severely affect living comfort, which is frequently encountered in various engineering applications. Managing this sound field relies heavily on the available prediction tools at hand, e.g., the widely used finite element methods are computationally expensive due to the necessity to discretize entire space, analytical models, based on modal expansion method, may offer substantial advantages in terms of computational cost and efficiency. However, deriving eigenmodes of irregular enclosed spaces may be challenging, which impedes accurate and rapid predictions of the sound field in practical applications. This study presents an analytical framework aimed at rapidly and accurately predicting the interior sound field driven by the piping system vibrations in irregular enclosures. Vibration response of the piping system is obtained using the wave approach, and a line dipole source is idealized as the sound source of the piping system vibration. On the basis of eigenmodes of regular enclosures, the Kirchhoff-Helmholtz integral theorem (modal expansion method for irregular enclosures) is introduced to account for the boundaries of irregular enclosures. This theoretical framework is validated through numerical simulations by finite element method and experiments, demonstrating high accuracy and significant efficiency advantages. The proposed method can be further employed to optimize radiated sound fields by tailoring the impedance of space walls or layout of piping systems. This study provides an efficient tool for predicting radiated sound field in general enclosures driven by vibration of piping systems, paving a new path for indoor acoustical optimization.

关键词： Partial slip contact   Goodman approximation   TE material   Periodic punches  

摘要： The study investigates the partial slip contact problem between thermoelectric material and periodic punches including flat and cylindrical punches under various loading conditions, including normal force, energy flux, and electric current density. When developing and enhancing thermoelectric devices intended for energy harvesting and temperature regulation, the relationship between punch geometry and thermoelectric material plays a crucial role. The periodic contact problem leads to the formation of a singular integral equation with a Hilbert kernel, distinguishing it from the traditional Cauchy kernel. It delves into the impact of the thermo-electric-mechanical coupling effect on the evolution of stick-slip zone length and contact stress during partial slip. By formulating the current nonlinear problem into a set of singular integral equations, the study identifies primary variables, including normal and tangential contact stresses, as well as slip and stick zones. The partial contact problem is further simplified by applying the Goodman approximation, enabling an iterative approach to determine the stick-slip zone, contact zone size, and stress distribution. Notably, the research reveals that factors such as the shape of the punch, the coefficient of friction, and TE parameters significantly influence stress strength and the characteristics of the stick-slip zone.

关键词： High-G droplets   Composite substrate   Wetting profile   Hypergravity condition   Scaling law   Energy distribution  

摘要： The wetting phenomenon of composite substrates in hypergravitational environment has a huge application in electronic devices and astronaut healthcare in aerospace missions. In the present contribution, the governing equation of high-G droplets on the composite substrate is firstly established in the hypergravitational environment. Meanwhile, the apparent contact angles at the contact line between droplets and substrates with different stiffness gradients are achieved. Then, we analyze the effects of hypergravity factor and the substrate stiffness on the wetting profile of high-G droplets. By introducing the droplet volume and contact angle into the Bond number, the scaling law of the high-G droplet profile is established, and we find that the contact radius of the droplet R/S-0.5 has a linear relationship with rho omega(2)rl(2)S/(gamma(LV)theta), while the droplet height H/S-0.5 has a power-law relationship with rho omega(2)rl(2)S / (gamma(LV)theta). Finally, we explain the profiles of high-G droplets during the wetting process by illustrating energy components of the entire system and find that the substrate with positive triangular stiffness and inverted triangular stiffness show opposite evolution laws. On a substrate with inverted triangular stiffness, the gravitational potential energy is more dominant.

摘要： 在过去10年中,生物医学研究领域经历了诸多变化,特别是在提高研究质量和透明度方面.各种指南为科研人员提供了更为严谨的规范,确保了研究结果的可靠性和可重复性.2021年"提高卫生研究质量和透明度(EQUATOR)协作网"提出了一项指南"生物医学文献中研究资源的特定识别:研究资源识别码(RRID)"(Unique identification of research resources in the biomedical literature:the Resource Identification Initiative(RRID)").RRID(研究资源识别码,Research Resource Identifier,RRID)是由FORCE 11("研究交流与数字学术未来"组织)小组于2014年推出的,其可有效解决生物资源的可重复性问题.

关键词： 表面缺陷检测   机器视觉   工业带材   深度学习   线性CCD   二维平面图像  

摘要： 工业带材表面缺陷检测是确保其产品质量的一个重要环节,目前工业带材在生产过程中常用传统面阵摄像头对产线上的带材进行视觉检测,而传统面阵摄像头受到其快门速度所限,导致检测效率低、受光源影响大。针对这些问题设计了一种基于线性CCD的工业带材缺陷智能检测系统。通过线性CCD采集传送带上工业带材表面图像数据,快速还原出二维平面图像,利用神经网络识别工业带材表面缺陷类型并记录位置,具有速度快、精度高的特点,应用前景较广阔。

关键词： 无创呼吸机   重症急性心衰   呼吸衰竭   心功能   血气指标  

摘要： 目的:探讨重症急性心衰合并呼吸衰竭临床治疗采用无创呼吸机辅助对患者心功能及血气指标的影响。方法:选取河南科技大学第二附属医院2020年1月至2024年2月收治的80例重症急性心衰合并呼吸衰竭患者为研究对象,按照随机数字表法分两组,各40例。对照组接受常规治疗,研究组在常规治疗基础上接受无创呼吸机辅助治疗。比较两组临床疗效,对比治疗前、后两组患者心功能及血清指标和血气指标水平。结果:较之对照组,研究组治疗后总有效率82.50%、心脏指数(cardiac index, CI)、射血分数(ejection fraction, EF)、氧合指数(oxygenation index, OI)、血氧饱和度(saturation of peripheral oxygen, SpO_(2))、血氧分压(partial pressure of oxygen, PaO_(2))均显著更高,左心室收缩末期内径(left ventricular end systolic diameter, LVEDs)、左心室舒张期内径(left ventricular end diastolic diameter, LVEDd)、C反应蛋白(C-reactive protein, CRP)、心肌肌钙蛋白I(cardiac troponin I,cTnI)、肌酸激酶同工酶(creatine kinase-MB,CK-MB)、氨基末端B型钠尿肽原(N-terminal pro-B-type natriuretic peptide, NT-proBNP)、二氧化碳分压(partial pressure of carbon dioxide, PaCO_(2))均显著更低(P<0.05);较之治疗前,治疗后CI、EF、OI、SpO_(2)、PaO_(2)均显著更高,LVEDs、LVEDd、CRP、cTnI、CK-MB、NT-proBNP、PaCO_(2)均显著更低(P<0.05)。结论:重症急性心衰合并呼吸衰竭临床治疗予以无创呼吸机辅助临床疗效显著,不仅在提高患者心功能方面效果明显,且还能改善血清及血气指标。

关键词： 叶类蔬菜   智能收割机   结构分析   概念设计  

摘要： 分析了常规叶类蔬菜收割机在技术实现、作物适应性和工作效率等方面的不足,从优化整体结构、动力系统、智能控制系统及收割模块方面着手,讨论了小型智能叶类蔬菜收割机的设计要素,以提升收割机的作业效率和适应性。通过引入智能传感技术和自动化控制系统,改进动力传动方式及收割模块,可以使收割机更好地适应复杂的田间环境,减少对蔬菜造成的损伤。

关键词： 社会认知交互训练   丙戊酸钠   老年躁狂症   认知功能   社会功能  

摘要： 目的:观察社会认知交互训练(SCIT)联合药物治疗对老年躁狂症患者病情控制及认知功能、社会功能的影响。方法:选取2021年6月至2024年6月河南省荣康医院老年躁狂症患者98例,按随机数表法分为对照组(丙戊酸钠治疗)和观察组(联合社会认知交互训练),各49例,观察两组疾病进程、认知功能和社会功能。结果:治疗3周、6周,观察组倍克-拉范森躁狂量表评分明显低于对照组(P<0.05);治疗后,观察组蒙特利尔认知评分明显高于对照组,社会功能障碍筛查表评分明显低于对照组(P<0.05)。结论:SCIT联合药物治疗有助于控制老年躁狂症患者疾病症状,能更大程度改善患者的认知功能和社会功能。

关键词： 物联网   绿色网点   网点管控系统   边缘网关   规则引擎   DotNET6   Agent Server边缘程序  

摘要： 为了解决银行营业网点末端设备种类繁多,人工管控方式效率低下,操作繁琐的问题,基于“云-管-边-端”物联网架构提出了网点管控系统,以实现绿色网点建设和运营。文中提出网点管控系统的设计方案,并进行了边缘网关的详细设计。使用DotNET6设计了一款Agent Server边缘程序,分为初始化模块、消息泵模块、核心业务模块、设备服务模块、规则引擎模块。在实际的绿色金融网点建设中进行网点管控系统的试点和测试,结果表明,该系统实现了网点的多种协议末端设备接入、智能化设备控制、能耗检测与分析、规则引擎场景联动等功能,助力银行建设绿色、低碳、节能的营业网点。