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关键词： 人体生理机能   药食同源   生物活性物质   矿物质元素   新陈代谢   饱腹感   免疫功能   营养价值  

摘要： 山药为薯蓣科植物薯蓣的干燥根茎,是一种药食同源食物,营养价值非常高;其营养成分主要有淀粉、蛋白质、维生素和矿物质元素,饱腹感较强,能改善和恢复人体的免疫功能,对维持人体生理机能和新陈代谢有着举足轻重的作用;生物活性物质丰富,主要有多糖。

关键词： 电动自行车   案件查办   执法检查   市场监管部门   产品质量监管   安全治理   监管执法   要点分析  

摘要： 市场监管部门承担着电动自行车生产、流通环节的产品质量监管执法工作,笔者结合电动自行车质量监管执法工作实际,从电动自行车及配件执行标准、执法检查要点、案件查办要点三个方面,对电动自行车质量执法检查与案件查办中的要点进行综合分析,以期有利于持续提升电动自行车质量安全治理水平。

关键词： 碎石泥岩边坡   边坡稳定性   降雨   地震  

摘要： 降雨和地震等自然作用对道路的安全施工、维护等有较大影响。以贵港市某升级改造道路旁的碎石泥岩边坡为例,采用数值模拟方法分析了边坡在3种强降雨和1种地震工况下的边坡稳定性变化。结果显示,在自然状态下,边坡体积含水量小,安全系数达1.307;当边坡逐渐达到饱和状态,其安全系数大幅下降,边坡由稳定变为基本稳定状态。在大雨、暴雨和大暴雨3种工况下,边坡安全系数下降至1.191、1.189和1.185,降雨时长为5d的强降雨对该边坡有一定影响,但未使得边坡达到饱和。地震对该边坡的影响较大,10s内边坡Y-相对位移由毫米级增大至分米级,边坡变形较为严重,在此情况下,边坡安全系数直接下降至0.988,边坡由稳定状态变为不稳定状态。综上,有必要根据实际情况,对该边坡进行后期加固以防止边坡失稳。

关键词： 热误差建模   切削力   支持向量回归   数控机床  

摘要： 为解决现有热误差建模方法依靠经验选择温度测量点,导致模型稳健性差等问题,提出一种基于切削力的机床主轴轴向热误差建模新方法。研究数控机床主轴轴向热误差对未变形切屑形貌的影响机制,建立考虑机床主轴轴向热误差的切削力模型,揭示相同切削工艺参数下的热误差致切削力演变规律;分析机床主轴轴向热误差与切削力的关联关系,利用支持向量回归建立基于切削力的机床主轴轴向热误差模型。与传统热误差模型相比,基于切削力的热误差建模方法不需要大量的温度传感器和复杂的温度敏感点确定过程,而且不用考虑温度敏感点动态变化对模型稳健性的影响。通过不同环境和工况下的实验证明,模型预测精度达到90%以上,具有较强的预测能力与泛化能力,为机床轴向热误差在线辨识提供了新方法,同时为机床在线误差补偿以及在智能制造过程中提升零件质量提供了技术基础。

关键词： 分布式模型   洪水预报   误差校正   LSTM   Transformer  

摘要： 中小河流产汇流情况复杂,洪水预报难度很大。为了提高中小河流洪水预报的精度,以河北省邢台市坡底流域为研究对象,分别基于蓄满产流和混合产流模式构建分布式模型进行降雨径流模拟。分别采用LSTM、Transformer、Transformer+LSTM叠加模型(TFLS)构建校正模型,采用差分进化算法对超参数进行优化。以实测降雨和分布式模型模拟结果为输入,对各时段的残差进行拟合,进而对径流模拟结果进行校正。研究结果表明,在17场洪水模拟结果中,混合产流模型表现优于蓄满产流。与混合产流模型相比,经TFLS校正后的模型洪峰误差不超过20%的场次从9场增加至12场,占全部场次的70.6%,确定性系数不低于0.8的场次从5场增加到9场,占比为52.9%。TFLS模型在流量不超过500 m^(3)/s时的校正效果优于LSTM和Transformer模型,LSTM模型对流量在500 m^(3)/s及以上的校正效果略优于其它模型。

关键词： Compressive Strength   GGBS   Metakaoline   Regression Analysis   Split Tensile Strength  

摘要： Historically, airfoil design optimization has been done through many different methods, or with the use of improving the aerodynamics in some ways as will be discussed below. Of all the PMS methods that are currently available in the literature, PARSEC marks itself out as the best fitting. One of the most effective methods for changing the shape of an airfoil because of high flexibility and accuracy. The current study aims to determine the utility of the PARSEC parameterization method on two airfoil models. Airfoils NACA 4412, and SG6043 within an angle attack of-10 to 15 degrees, by employing a genetic algorithm. The reliability of the PARSEC method is also assessed by reconstructing the geometries of the airfoil and then comparing the shapes with the original airfoils where these characteristics have a significant influence on the airfoil efficiency. For instance lift coefficient (CL), drag coefficient (CD), and the ratio CL/Cd at different angles of attack. The study also includes the improvement of the aerodynamic design of both airfoils through the use of a genetic algorithm which is coded and run in MATLAB, with the PARSEC parameters used as the base for optimization. It is also important for one to conduct some comparisons between the PARSEC-optimized airfoils and the standard airfoil. The performance of the PARSEC method in making the wing shape the same and similar to the original one is accurate. Aerodynamic characteristics. Significantly, the same was realized in the optimized airfoil and the original airfoil which recorded the maximum pushover speed, drag, and lift characteristics to ±0.3 at an angle of attack of 8 ° and Reynolds number of 10 e5. This paper supports the efficiency of the used PARSEC parameterization. It is found to act as an effective means of support to engineers and researchers who would like to use this method to improve airfoil’s characteristics in aviation, and aeronautical, Such as aerospace applications, and wind turbines. The fin

关键词： 羊肚菌   菌种   土壤   营养袋   催菇   病虫害  

摘要： 羊肚菌因其价格高、味道鲜美、栽培操作简单、栽培周期短等特点,吸引大量栽培户。总结介绍羊肚菌栽培菌株、栽培地块选择,播种时间、播种覆土、出菇管理等方面的关键技术节点,以期为北方暖棚羊肚菌的栽培户提供实用的技术指导。

关键词： Battery management system C rate   characterization test   Electric vehicles   Hybrid pulse power   MATLAB   State of charge  

摘要： Electric vehicles are the trend of this decade. Frequent high-power requirements of electric vehicles, make the batteries discharge at higher C rate. Discharging at a higher C rate will lead to higher heat production leading to destruction and explosion of the battery. To optimize the charging and discharging C rates considering both safety and performance factors, battery management system (BMS) is used as an eternal component of power source. To estimate the state of charge (SOC), which is an essential component of BMS, accurate battery modelling is required. Two RC model is one of the most used lithium-ion battery model, due to its simplicity and accuracy. The equivalent circuit parameters, resistances and capacitance do change with SOC and temperatures. This paper focuses on estimation of equivalent circuit parameters for a wide range of temperatures and SOCs ranging from -20 degree celsius to +25 degree celsius and 100 to 0 respectively. We have developed two RC model for Panasonic 18650PF and estimated the parameters of the model using hybrid pulse power characterization (HPPC) data. MATLAB based parameter estimator is used in determining the equivalent circuit parameters. © 2025 Institute of Advanced Engineering and Science. All rights reserved.

关键词： Electrode   Grounding resistance   Grounding system   MATLAB graphical user interface   Modelling   Substation  

摘要： The grounding system in substations generally uses electrode rods, because electrodes can affect the effectiveness of fault current conduction, so the equipment will be safer. Considering the importance of the grounding system, the installed grounding system must be considered and maintained properly. One of them is the grounding found in Glugur. The main objective of this research is to comprehensively evaluate the substation grounding system by modeling the grounding system at the Glugur Substation using MATLAB graphical user interface (GUI). The grounding resistance follows a grid system with an area of 20×15=300 m with specific resistance being clay using 100 rod electrodes. From the results of ground resistance simulation modeling using MATLAB GUI, it can be concluded as follows: for a certain resistance value, the number of electrodes for 100 ωm is 3.55 ω, for ground resistance with a constant depth and a varying number of 100 electrodes, it is 3.45 ω, and for. The grounding resistance with a constant and varying number of 1,000 rods is obtained at 2.65 ω. From these results, the modeling carried out is in accordance with the standards of electricity regulations in Indonesia. © 2025 Institute of Advanced Engineering and Science. All rights reserved.

关键词： 慢性胰腺炎   保留十二指肠   胰头整块切除术   Oddi’s括约肌   胰头良性肿瘤  

摘要： 慢性胰腺炎,胰头良性、交界性及低度恶性肿瘤的外科治疗效果明确,如何保留更多的功能器官是此类手术的关注重点。笔者团队首创的保留十二指肠、胆总管、Oddi’s括约肌的胰头整块全切除术相较于其他术式具有理论上的优势,但因手术操作难度大,对术者要求更高而限制其广泛开展。笔者通过阐述该手术的发明原理和演变历程,解析关键步骤并展示临床效果,证明该手术安全有效,具有较高的临床应用价值。