A Hybrid Optimization Approach of Single Point Incremental Sheet Forming of AISI 316L Stainless Steel Using Grey Relation Analysis Coupled with Principal Component Analysiss

We investigated the parametric optimization on incremental sheet forming of stainless steel using Grey Relational Analysis(GRA) coupled with Principal Component Analysis(PCA). AISI 316L stainless steel sheets were used to develop double wall angle pyramid with aid of tungsten carbide tool. GRA coupled with PCA was used to plan the experiment conditions. Control factors such as Tool Diameter(TD), Step Depth(SD), Bottom Wall Angle(BWA), Feed Rate(FR) and Spindle Speed(SS) on Top Wall Angle(TWA) and Top Wall Angle Surface Roughness(TWASR) have been studied. Wall angle increases with increasing tool diameter due to large contact area between tool and workpiece. As the step depth, feed rate and spindle speed increase,TWASR decreases with increasing tool diameter. As the step depth increasing, the hydrostatic stress is raised causing severe cracks in the deformed surface. Hence it was concluded that the proposed hybrid method was suitable for optimizing the factors and response.

Optimization of short-circuit transition parameters of Q235B steel GMAW based on orthogonal gray relational analysis

In gas metal arc welding(GMAW)process,the short-circuit transition was the most typical transition observed in molten metal droplets.This paper used orthogonal tests to explore the coupling effect law of welding process parameters on the quality of weld forming under short-circuit transition,the design of 3 factors and 3 levels of a total of 9 groups of orthogonal tests,welding current,welding voltage,welding speed as input parameters:effective area ratio,humps,actual linear power density,aspect ratio,Vickers hardness as output paramet-ers(response targets).Using range analysis and trend charts,we can visually depict the relationship between input parameters and a single output parameter,ultimately determining the optimal process parameters that impact the single output index.Then combined with gray the-ory to transform the three response targets into a single gray relational grade(GRG)for analysis,the optimal combination of the weld mor-phology parameters as follows:welding current 100 A,welding voltage 25 V,welding speed 30 cm/min.Finally,validation experiments were conducted,and the results showed that the error between the gray relational grade and the predicted value was 2.74%.It was observed that the effective area ratio of the response target significantly improved,validating the reliability of the orthogonal gray relational method.

Isogeometric Analysis of Hyperelastic Material Characteristics for Calcified Aortic Valve

This study explores the implementation of computed tomography(CT)reconstruction and simulation techniques for patient-specific valves,aiming to dissect the mechanical attributes of calcified valves within transcatheter heart valve replacement(TAVR)procedures.In order to facilitate this exploration,it derives pertinent formulas for 3D multi-material isogeometric hyperelastic analysis based on Hounsfield unit(HU)values,thereby unlocking foundational capabilities for isogeometric analysis in calcified aortic valves.A series of uniaxial and biaxial tensile tests is executed to obtain an accurate constitutive model for calcified active valves.To mitigate discretization errors,methodologies for reconstructing volumetric parametric models,integrating both geometric and material attributes,are introduced.Applying these analytical formulas,constitutive models,and precise analytical models to isogeometric analyses of calcified valves,the research ascertains their close alignment with experimental results through the close fit in displacement-stress curves,compellingly validating the accuracy and reliability of the method.This study presents a step-by-step approach to analyzing themechanical characteristics of patient-specific valves obtained fromCT images,holding significant clinical implications and assisting in the selection of treatment strategies and surgical intervention approaches in TAVR procedures.

Correlation analysis of longitudinal cracks and vertical deformation within asphalt pavement of cold regions

The asphalt pavement longitudinal crack is a common distress in cold regions,resulting from uneven deformation of the subgrade.Analysis of the correlation law between uneven deformation and crack distress is of positive significance for understanding the mechanism of crack initiation,and putting forward treatment measures.In view of the complexity of longitudinal crack inducement and road surface deformation,the grey relational method was used to analyze this relationship.Through long-term monitoring of the vertical deformation data of typical road sections,the vertical deformation law of the pavement surface and its deformation characteristics under the action of temperature field are analyzed.Parameters such as vertical relative deformation,vertical relative deformation rate and vertical differential deformation VDSr were constructed to describe vertical deformation characteristics.Typical distribution characteristics of longitudinal fractures and their length and distribution characteristics are also described.The grey correlation analysis theory was utilized to analyze the relationship between deformation characteristics of sections,cross sections and monitoring points and longitudinal crack characteristics(length and location).The analysis reveals a linear positive correlation or a high correlation between several indicators.This study can provide a deeper understanding of the occurrence and development mechanism of longitudinal cracks in asphalt pavement of cold areas,and give references for the research of road engineering structure,materials and distress prevention.

Materials Selection of Thermoplastic Matrices of Natural Fibre Composites for Cyclist Helmet Using an Integration of DMAIC Approach in Six Sigma Method Together with Grey Relational Analysis Approach

Natural fibre reinforced polymer composite(NFRPC)materials are gaining popularity in the modern world due to their eco-friendliness,lightweight nature,life-cycle superiority,biodegradability,low cost,and noble mechanical properties.Due to the wide variety of materials available that have comparable attributes and satisfy the requirements of the product design specification,material selection has become a crucial component of design for engineers.This paper discusses the study’s findings in choosing the suitable thermoplastic matrices of Natural Fibre Composites for Cyclist Helmet utilising the DMAIC,and GRA approaches.The results are based on integrating two decision methods implemented utilising two distinct decision-making approaches:qualitative and quantitative.This study suggested thermoplastic polyethylene as a particularly ideal matrix in composite cyclist helmets during the selection process for the best thermoplastic matrices material using the 6σtechnique,with the decision based on the highest performance,the lightest weight,and the most environmentally friendly criteria.The DMAIC and GRA approach significantly influenced the material selection process by offering different tools for each phase.In the future study,selection technique may have been more exhaustive if more information from other factors had been added.

Multi-Criteria Group Decision-Making Method Based on an Improved Single-Valued Neutrosophic Hamacher Weighted Average Operator and Grey Relational Analysis

This paper proposes a multi-criteria decision-making (MCGDM) method based on the improved single-valued neutrosophic Hamacher weighted averaging (ISNHWA) operator and grey relational analysis (GRA) to overcome the limitations of present methods based on aggregation operators. First, the limitations of several existing single-valued neutrosophic weighted averaging aggregation operators (i.e. , the single-valued neutrosophic weighted averaging, single-valued neutrosophic weighted algebraic averaging, single-valued neutrosophic weighted Einstein averaging, single-valued neutrosophic Frank weighted averaging, and single-valued neutrosophic Hamacher weighted averaging operators), which can produce some indeterminate terms in the aggregation process, are discussed. Second, an ISNHWA operator was developed to overcome the limitations of existing operators. Third, the properties of the proposed operator, including idempotency, boundedness, monotonicity, and commutativity, were analyzed. Application examples confirmed that the ISNHWA operator and the proposed MCGDM method are rational and effective. The proposed improved ISNHWA operator and MCGDM method can overcome the indeterminate results in some special cases in existing single-valued neutrosophic weighted averaging aggregation operators and MCGDM methods.

6个苇状羊茅(型)品种在成都平原区的生产性能评价

为筛选适宜成都平原推广利用的优异牧草品种,对6个苇状羊茅(型)品种进行了生育期、主要农艺性状、鲜(干)草产量及牧草营养成分等指标的测定,并运用灰色关联度分析进行综合评价。结果表明,‘特沃’和‘科瑞’的生育期最长,均达275 d。各参试品种平均再生速度依次为‘马胡丽娜’>‘科瑞’>‘都脉’>‘特沃’>‘K31’>‘福泰’。品种‘马胡丽娜’年平均干草产量最高,可达12790.99 kg·hm-2,分别较国审品种‘特沃’和‘都脉’显著增加14.62%和4.28%(P<0.05),表现出明显的产量优势。‘科瑞’干草产量较‘特沃’显著增加6.59%(P<0.05),且植株自然高度可达100.15 cm,高于‘特沃’和‘都脉’(P<0.05)。‘都脉’的分蘖数最大,为47.33个·株^(-1),显著高于其他品种(P<0.05),其次是‘科瑞’和‘马胡丽娜’,分别达37.50和37.00个·株^(-1),较品种‘特沃’多6.25和5.75个·株^(-1)。‘K31’茎叶比为0.96,高于其他参试品种。对6个参试品种的营养成分测定表明,‘特沃’的粗蛋白含量最高,可达18.60%,‘科瑞’的粗脂肪含量最高,可达5.41%。通过灰色关联度法综合比较分析,‘科瑞’表现最优,‘特沃’和‘马胡丽娜’综合性状表现较优,适宜在成都平原地区推广种植利用。

基于季节性碳交易机制的园区综合能源系统低碳经济调度

为有效提高碳排放配额分配的合理性,并且避免年度结算时碳排放量超标导致环境污染加剧问题,提出基于奖惩因子的季节性碳交易机制,以园区综合能源系统(park integrated energy system,PIES)为对象进行低碳经济调度。首先,构建包含能量层–碳流层–管理层的综合能源系统(integrated energy system,IES)运行框架,建立电气热多能流供需动态一致性模型;其次,分析系统内“日–季节–年度”碳排放特性,打破传统应用指标法的配额分配方法,采用灰色关联分析法建立碳排放配额分配模型,并基于奖惩阶梯碳价制定季节性碳交易机制;最后,以系统内全寿命周期运行成本及碳交易成本最小为目标,对执行季节性碳交易机制的PIES进行低碳经济调度,分析长时间尺度下季节性储能参与调度的减碳量。搭建IEEE 33节点电网5节点气网7节点热网的PIES,并基于多场景进行算例分析,验证此调度方法能够实现零碳经济运行,保证系统供能可靠性,为建立零碳园区奠定理论基础。

使用双膦酸盐药物患者种植体早期失败率及术后药物相关性颌骨坏死的单组率Meta分析

目的系统评价使用双膦酸盐药物(bisphosphonates,BPs)患者种植体早期失败率及种植术后药物相关性颌骨坏死(medication-related osteonecrosis of the jaw,MRONJ)发生率,为临床评估相关风险提供依据。方法计算机检索Cochrane Library、Wiley Online Library、PubMed、中国知网、万方数据知识服务平台,收集纳入各数据库建库至2022年5月发表的关于使用BPs患者种植体早期失败或种植术后发生MRONJ的临床研究。采用Stata 15.0软件对种植体早期失败率进行单组率Meta分析。结果共纳入13篇文献,其中口服BPs患者植入1182颗种植体,静脉注射BPs患者植入79颗,共计1261颗种植体。口服BPs患者合并种植体早期失败率为1.7%(95%CI:0.3%~3.9%),MRONJ发生率为0。静脉注射BPs患者种植体早期失败率为0,MRONJ发生率为5.6%。结论口服BPs患者种植体早期失败率及术后MRONJ发生率低,与健康人群基本相当。静脉使用BPs患者种植术后发生MRONJ风险较高,临床适应证选择应慎重。

含大规模分布式光伏接入电网的无功电压控制降损方法研究

大规模分布式光伏(distributed photovoltaic,DP)接入电网后,电网电压易出现大幅度波动,导致电网损失问题越来越突出。当前已有的电网降损方法没有考虑光伏发电自身的无功调节能力,应用效果不理想。为此,设计一种含大规模DP接入电网的无功电压控制降损方法。通过建立目标函数,设定约束条件,采用敏感性分析方法分析电压稳定性,将敏感度较高的值作为无功补偿位置,并对当前负荷进行预测,确定最佳的补偿容量,实现电网降损。试验结果表明:所提方法降损后较降损前基准电压更趋于1 pu,更为稳定,所提方法能够针对光伏控制接入分布特性,有效控制无功功率变化情况,相对于其他方法,无功功率波动较小,表现出较好的降损效果。

灰关联分析在医院财务管理中的应用研究

[目的]探讨灰关联分析在医院财务管理中的应用,为医院管理高质量发展提供借鉴。[方法]收集湖北省武汉市某三甲医院2017-2022年的门诊收入数据,计算门诊药费、门诊检查费、门诊挂号费和门诊其他收入与门诊总收入的灰关联度。[结果]计算得到灰关联度排序为门诊挂号费(0.839)>门诊检查费(0.643)>门诊药费(0.626)>门诊其他收入(0.543)。[结论]灰关联分析能帮助医院在财务管理上理解收入结构、提供决策支持、加强风险管理和预测未来趋势,在医院绩效管理上帮助医院辅助绩效评估,制定激励措施和优化资源配置。

基于点分配法、全一致性法、灰色关联分析的科技人才分类评价研究

科技人才评价是一种多准则决策问题,不同方法导致评估存在不确定性,已有相关评价方法在实践中存在一定的局限性。为解决这一问题,针对创新活动不同阶段对科技人才评价的差异化要求,立足于“破四唯”和“立新标”并举的思路,将科技人才分为基础研究类、应用研究和技术开发类以及科技管理服务类,基于政策文件和文献的关键词提取法构建科技人才分类评价指标体系,通过充分考虑不同方法导致评估存在的不确定性,结合点分配法(PA)和全一致性法(FUCOM)构建灰数组合权重,将灰数权重和不同决策者针对评价对象的评估分数作为灰数输入,提出PA-FUCOM灰色关联分析法;并以陕西省某研究院的4位应用研究和技术开发类人才为例进行实证分析,以验证评价结果的有效和准确性。结果表明:基于PA-FUCOM灰色关联分析法的科技人才评价指标体系,对基础研究人才整体上各类指标相对较为均衡但侧重人才价值和学科背景,对应用研究和技术开发类人才在成果价值和转化效益上拥有更大的权重,对科技管理服务类人才整体指标相对均衡但在成果价值上的权重相对更大;灰色系统理论有助于解决科技人才评价过程存在的不确定性,点分配法在实际评估中简单可行,FUCOM由于计算量小、一致性更高从而为混合指标权重计算提供了新的可能,因此PA-FUCOM组合权重计算方法在评价结果区分度、评价结果的一致性上都有较好的表现.

关系框架理论模型的最新发展:从MDML到HDML

关系框架理论是美国心理学家Hayes等人于1985年提出的基于行为分析的当代语言与认知理论。关系框架理论将一类由语境控制并明确规定了刺激之间关系的反应称为任意适用的关系反应,并将其作为关系框架理论的基本过程。文章系统梳理了关系框架理论的最新发展,包括研究者对早期关系框架理论研究的反思、最近几年发展出来的多维度多水平模型和超维度多水平模型,并对理论的发展进行了总结和评价,提出了未来的研究方向,以期为该理论在中国的实证研究和发展提供参考。

12个燕麦品种在黄土高原沟壑区生产性能及适应性

为筛选适宜黄土高原沟壑区种植的高产、抗倒伏、抗病性强的燕麦(Avena sativa)品种,以国内外引进的12个燕麦品种为试验材料,分析其产量相关性状、倒伏率和病害发生率,并利用灰色关联度分析和聚类分析法进行综合评价。结果表明:12个燕麦品种干草产量为10800.00~15233.33 kg·hm^(−2),平均干草产量13298.61 kg·hm^(−2);种子产量为3095.24~7857.14 kg·hm^(−2),平均值5407.14 kg·hm^(−2);其中,‘坝燕6号’的倒伏率较低,红叶病和锈病发病率最低,为抗倒伏兼抗病品种。灰色关联度分析结果表明:株高、干草产量、叶茎比在灰色关联评价系统中所占权重最高,是品种选择时的重要指标。采用聚类分析方法将12个燕麦品种划分为3个类群,第Ⅰ类群可作为饲草品种,第Ⅱ类群可作为籽粒型品种,第Ⅲ类群倒伏率及病情指数低,抗逆性好。综合灰色关联度和聚类分析方法,筛选出适宜黄土高原沟壑区种植的产量高、适应性好的饲草型燕麦品种‘加燕2号’,籽粒型燕麦品种‘坝燕6号’和‘美达’。

天山北坡平原荒漠灌区9个紫花苜蓿品种生产性能综合评价

【目的】筛选出适宜在天山北坡平原荒漠区推广种植的紫花苜蓿品种。【方法】采用单因素随机区组设计,测定9个紫花苜蓿品种的株高、草产量、品质等指标,并利用灰色关联法对9个品种进行综合评价。【结果】随种植年限增加,供试材料的鲜草和干草产量均呈下降趋势,其中第1年的干草产量占比较高,平均为37.77%;佰苜341的株高积累量最大,为939.8 cm,显著高于其他品种;骑士T干草总产量、粗蛋白含量和相对饲喂价值最高,分别为61602.03 kg/hm^(2)、16.83%和119.16%;灰色关联度综合评价结果由高到低的顺序为:骑士T>佰苜202>大银河>阿迪娜>佰苜341>佰苜371>挑战者>佰苜401>康赛。【结论】骑士T的综合表现较好,建议在天山北坡平原荒漠灌区引种种植。

注射用亚胺培南西司他丁钠质量分析

目的 对国内市场中不同企业的注射用亚胺培南西司他丁钠的质量状况进行评价,发现质量风险点,为仿制药一致性评价提供质量控制关键点。方法 采用法定检验结合探索性研究的方法对样品进行检验,统计分析注射用亚胺培南西司他丁钠的整体质量水平,分析不同企业产品的差异。结果 按法定标准检验,80批次抽验样品结果均符合规定。但发现原研产品的复溶时间更快;不同企业的产品有关物质和含量结果差异较大;现行质量标准差异较大亟待提高统一。探索性研究表明,样品复溶时间与制剂中亚胺培南晶癖及粒度相关;采用LC/MS等方法对本品有关物质的来源进行了归属,对部分杂质结构进行了推断;对本品的含量测定方法进行了优化。结论 国内市场中注射用亚胺培南西司他丁钠的质量总体较好;在开展仿制药一致性评价工作中,需关注亚胺培南的晶癖以及制剂的有关物质、含量、充氮工艺和异亚丙基丙酮等质量关键点;现行标准有待统一和提高。

山药块茎生长膨大相关基因的筛选与分析

为筛选山药块茎生长膨大相关基因,采用生物信息学方法,对山药块茎发育前期和中期构建的不同发育阶段抑制性消减杂交(suppression subtractive hybridization,SSH)文库进行分析。结果表明:山药块茎发育前期与中期差异表达基因(differential expression genes,DEGs)序列主要涉及九大类,其中发育调控占比最大(27.1%),其他依次为细胞组织结构(14.0%)、物质代谢(11.2%)、生物合成(4.7%)等。初步筛选出泛素-连接酶体(F-box associated,F-box)、碳酸酐酶(carbonic anhydrase,CAs)、核苷二磷酸激酶(nucleoside diphosphate kinase,NDPK)、氨基酸透性酶(amino acid permease)、糖基转移酶(glycosyl transferase)、α-淀粉酶(α-amylase,AMY)等候选基因,它们可能与细胞增殖、细胞伸长、激素代谢、酸碱环境调节及功能物质代谢物等功能有关,参与调控山药块茎的生长膨大。

女性绝经相关症状特点及绝经激素治疗认知状况的调查分析

目的 调查更年期女性绝经相关症状的特点及对绝经激素治疗(MHT)的认知状况。方法 选择就诊于西安交通大学第一附属医院有绝经相关症状的619例更年期女性为研究对象,采用调查问卷的方式收集资料,分析绝经相关症状的特点,探讨更年期女性对MHT的认知状况及疗效。结果 371例围绝经期女性中绝经相关症状发生率位于前3位的分别是:疲乏(69.81%)、失眠(66.85%)、潮热出汗(58.22%),248例绝经后女性中绝经相关症状发生率位于前3位的分别是:潮热出汗(64.11%)、骨关节痛(60.89%)、疲乏(56.85%)。绝经后女性的失眠、疲乏发生率显著低于围绝经期女性(P<0.01),而骨关节痛、泌尿系感染、阴道干涩性交痛的发生率显著高于围绝经期女性(P<0.01)。围绝经期和绝经后女性的Kupperman评分比较无统计学差异(P>0.05),但评分程度分布比较有统计学差异(P<0.05);围绝经期女性轻度占比最高,绝经后女性中度占比最高。绝经后女性的不同绝经年龄、绝经年限、绝经方式之间Kupperman评分比较有统计学差异(P<0.05);绝经年龄越早、绝经年限越短Kupperman评分越高;手术绝经者Kupperman评分显著高于自然绝经者(P<0.05)。多因素Logistic回归分析结果显示,年龄45~54岁、退休或无业、配偶疾病或去世、性生活不正常、文化程度高是绝经相关症状发生的危险因素(P<0.05),家庭收入高、>3次/周的运动是绝经相关症状发生的保护因素(P<0.05)。更年期女性对MHT了解途径占比最高为网络(39.92%),对MHT的担忧占比最高为肿瘤(33.67%)。465例(89.77%)无MHT禁忌证的更年期女性,治疗后症状显著改善(P<0.05)。结论 更年期女性绝经相关症状显著,年龄越早、绝经年限越短及手术绝经者症状更为严重,应关注绝经对更年期女性健康的影响并增加专业医师指导,提高MHT使用率以改善更年期女性的生活质量。

基于拖拉机姿态特征的意象认知研究

目的挖掘拖拉机姿态与意象偏好的关系,进而指导拖拉机的造型设计。方法采用多元尺度分析法和聚类分析法筛选拖拉机的姿态样本;运用形态分析法分解并标定典型样本的姿态特征,通过语词聚类实验构建拖拉机姿态的意象空间;结合语义差分法和问卷调研获取用户对典型拖拉机样本的意象偏好,运用灰色关联分析法得到拖拉机姿态特征与意象的关联。结果得到拖拉机的8个典型姿态样本,获取了拖拉机姿态的四个语义维度下的五个代表性语义词对。明确了拖拉机姿态的特征框架和语义结构,归纳得到拖拉机姿态的意象认知规律。结论拖拉机的姿态特征蕴含着意象信息,研究结果可以为设计师解读用户的意象认知提供参考。

基于GRA-GRU的淮河流域水质预测研究

水质指标具有多元相关性、时序性和非线性的特点,为有效预测河流水质变化,针对水质数据存在缺失和异常的问题,提出基于灰色关联分析-门控循环单元(Grey Relational Analysis-Gated Recurrent Unit, GRA-GRU)的水质预测模型。以淮河流域水质数据为样本,使用线性插值修补缺失数据和剔除的异常数据。使用灰色关联分析计算不同水质指标间的相关性,选择高相关性的水质指标以确定输入变量,并使用门控循环单元(Gated Recurrent Unit, GRU)预测不同的水质指标。将GRA-GRU的预测结果与反向传播神经网络(Back Propagation Neural Network, BPNN)、循环神经网络(Recurrent Neural Network, RNN)、长短期记忆神经网络(Long Short Term Memory, LSTM)、GRU及灰色关联分析-长短期记忆神经网络(Grey Relational Analysis-Long Short Term Memory, GRA-LSTM)进行对比分析,结果显示GRA-GRU在不同水质指标预测上具有较好的适应性,可以有效降低预测误差。其中,与其他模型相比,GRA-GRU预测的化学需氧量在均方根误差上分别降低了3.617%、0.681%、0.478%、1.505%和0.471%。