Approximation Maintenance When Adding a Conditional Value in Set-Valued Ordered Decision Systems

The integration of set-valued ordered rough set models and incremental learning signify a progressive advancement of conventional rough set theory, with the objective of tackling the heterogeneity and ongoing transformations in information systems. In set-valued ordered decision systems, when changes occur in the attribute value domain, such as adding conditional values, it may result in changes in the preference relation between objects, indirectly leading to changes in approximations. In this paper, we effectively addressed the issue of updating approximations that arose from adding conditional values in set-valued ordered decision systems. Firstly, we classified the research objects into two categories: objects with changes in conditional values and objects without changes, and then conducted theoretical studies on updating approximations for these two categories, presenting approximation update theories for adding conditional values. Subsequently, we presented incremental algorithms corresponding to approximation update theories. We demonstrated the feasibility of the proposed incremental update method with numerical examples and showed that our incremental algorithm outperformed the static algorithm. Ultimately, by comparing experimental results on different datasets, it is evident that the incremental algorithm efficiently reduced processing time. In conclusion, this study offered a promising strategy to address the challenges of set-valued ordered decision systems in dynamic environments.

APPLICATION OF ROUGH SET THEORY TO MAINTENANCE LEVEL DECISION-MAKING FOR AERO-ENGINE MODULES BASED ON INCREMENTAL KNOWLEDGE LEARNING

The maintenance of an aero-engine usually includes three levels,and the maintenance cost and period greatly differ depending on the different maintenance levels.To plan a reasonable maintenance budget program, airlines would like to predict the maintenance level of aero-engine before repairing in terms of performance parameters,which can provide more economic benefits.The maintenance level decision rules are mined using the historical maintenance data of a civil aero-engine based on the rough set theory,and a variety of possible models of updating rules produced by newly increased maintenance cases added to the historical maintenance case database are investigated by the means of incremental machine learning.The continuously updated rules can provide reasonable guidance suggestions for engineers and decision support for planning a maintenance budget program before repairing. The results of an example show that the decision rules become more typical and robust,and they are more accurate to predict the maintenance level of an aero-engine module as the maintenance data increase,which illustrates the feasibility of the represented method.

Clinical study of predicting the occurrence and development of coronary heart disease by FT3 level in maintenance hemodialysis patients

Objective:To investigate the clinical significance of FT3 level in predicting the occurrence and development of coronary heart disease in maintenance hemodialysis patients.Methods:95 Patients who underwent maintenance hemodialysis in our hospital from January 2016 to December 2017 were selected as subjects. According to whether has coronary heart disease was divided into coronary heart disease group and non coronary heart disease group, the difference of FT3 level and related laboratory indexes was observed. ROC curve analysis and COX multiple factor risk regression were used to analyze the predictive value of FT3 level on the occurrence and development of heart disease in MHD patients.Results:The concentration of FT3, Hb and ALB in CHD group was lower than that of non-CHD group (P<0.05), and the content of TG, TC, LDL-C, Hcy and Hs-CRP were significantly higher than that of non-CHD group (P<0.05). FT3 was positively correlated with Hb and ALB (T=0.821, 0.809,P<0.05), and was negatively correlated with TG, TC, LDL-C, Hcy and Hs-CRP (T=- 0.814, - 0.843, - 0.904, - 0.806, - 0.912,P<0.05). The ROC curve analysis showed that the area of AUC of FT3 was the highest, 0.864 (95%, CI:0.803~0.935), the sensitivity and specificity was 86.5% and 89.3% respectively. The area of combined diagnosis of AUC was 0.904 (95%CI:0.867~0.976), the sensitivity and specificity was 85.6% and 94.5%, respectively. After analyzing the COX risk regression model and correcting the above laboratory indicators, FT3 is an independent risk factor (HR: 0.58, 95%, CI: 0.41~0.72,P<0.05) for the adverse prognosis of MHD patients with coronary heart disease.Conclusion:It is of high clinical value to predict the development of coronary heart disease in MHD patients by FT3 level, and its mechanism may be related to the reduction of thyroxine synthesis, inflammatory reaction and atherosclerosis.

Quality-Oriented Facade Systems： Technical Data Referred to Maintenance Phase and Residual Value

Nowadays, clients require solutions that are efficient during the service life as a whole. In this view, maintenance has functional value and greatly contributes to increasing quality in environments. With reference to maintenance phase and residual value of building products upon dismantling, the present manuscript investigates a set of technological packages of quality and technical value referred to two alternative facade systems available for recovery actions on Italian council buildings--the ETICS （external thermal insulation composite system） and the external cladding system--complying with one thermal-insulation strategy, but different in terms of service life duration. Preservation of technical value and value increases are strictly related to maintenance quality and efficiency. Volume of investments in maintenance is not the only parameter to be considered to assess facade-system-management quality. Time-accurate economic assessment requires the entity to be related to periodical checks on performance quality in the building system and in its parts. Effective technical data to draw up consistent estimates and appraisals are rarely available in literature. With all that stated above, the present manuscript aims at introducing technical data related to drawing up reliable cost estimates and effective appraisals in terms of economics, quality and environmental sustainability. Conclusions will be drawn from the end of the manuscript.

SOME RESULTSON LAG INCREMENTSOF PRINCIPAL VALUE OF BROWNIAN LOCAL TIME

Let W be a standard Brownian motion,and define Y(t) =∫t 0 ds W(s) as Cauchy' s principal value related to the local time of W.We study some limitresults on lag increments of Y(t) and obtain various results all of which are related to earlier work by Hanson and Russo in 1 983

“Products-Knowledge” Two-Dimensional Increment Model of Fashion Industry Value Chain Based on Industry Analysis

Fashion industry has a complex characteristic for it spans the first, second, and third industries. In addition, the characteristic of creative industry has high value-added for its knowledge outputting, which makes the traditional value-added analysis based on supply chain not easy and good enough to interpret its industry value-added features. From the perspective of "products-knowledge" two-dimensional analysis,a fashion industry value chain increment model is built,by simulating the process of "product flow" and "information flow" value-added. The fashion industry value chain increment model provides an effective way for the enterprise strategy formulation and production strategy adjustment.

Improving convergence of incremental harmonic balance method using homotopy analysis method

We have deduced incremental harmonic balance an iteration scheme in the （IHB） method using the harmonic balance plus the Newton-Raphson method. Since the convergence of the iteration is dependent upon the initial values in the iteration, the convergent region is greatly restricted for some cases. In this contribution, in order to enlarge the convergent region of the IHB method, we constructed the zeroth-order deformation equation using the homotopy analysis method, in which the IHB method is employed to solve the deformation equation with an embedding parameter as the active increment. Taking the Duffing and the van der Pol equations as examples, we obtained the highly accurate solutions. Importantly, the presented approach renders a convenient way to control and adjust the convergence.

Moments and limiting distribution of a portfolio of whole life annuity policies

A dual random model of a portfolio of variable amount whole life annuity is set with the mth moment of the present value of benefits, and the respective expressions of the moments under the assumption that the force of interest accumulation function is Wiener process or Ornstein-Uhlenbeck process. Furthermore, the limiting distribution of average cost of this portfolio is discussed with the expression of the limiting distribution under the assumption that the force of interest accumulation is an independent increment process.

Industrial Heritage Protection in the Period of Inventory Planning

After entering the 21 st century,under the influence of urbanization and industrial transformation,China's industrial heritage protection is faced with enormous challenges.In the next 10 years,China's urban planning will enter a turning period from increment planning to inventory planning.Among objects of effective land use,industrial use will stand in the breach,which pushes the industrial heritage to the crossroad of protection or non-protection.Therefore,it is essential to study how to effectively use industrial land under the premise of protecting industrial heritage value.In view of these issues,this paper presents some thoughts about how to protect cultural value of industrial heritage in the period of inventory planning.

A NOTE ON SAMPLE PATH PROPERTIES OF l^p-VALUED GAUSSIAN PROCESSES

The a.s. sample path properties for l p valued Gaussian processes with stationary increments under some more general conditions are established.

定量CMR参数对急性心肌炎诊断的增量价值研究

目的探究定量心脏磁共振(CMR)参数对急性心肌炎诊断的增量价值。方法选取2021年12月至2023年12月新乡市中心医院收治的120例急性心肌炎患者(急性心肌炎组)进行回顾性研究,另按2∶1比例选取本院体检健康者60例作为对照组,比较两组受检者的定量CMR参数,通过受试者工作特征曲线(ROC)分析定量CMR参数诊断急性心肌炎的价值效能,并对定量CMR参数进行中位数划分,分析定量CMR参数增量诊断急性心肌炎的价值。结果急性心肌炎组患者T1弛豫时间、T2信号强度比、早期强化率明显高于对照组,差异均有统计学意义(P<0.05);ROC分析结果显示,T1弛豫时间、T2信号强度比、早期强化率诊断急性心肌炎的曲线下面积(AUC)分别为0.783、0.798、0.644。急性心肌炎组患者T1弛豫时间、T2信号强度比、早期强化率值的中位数分别为1310.5 ms、2%、3.51%。按中位数将其划分为T1弛豫时间≥1310.5 ms亚组,T1弛豫时间<1310.5 ms亚组;T2信号强度比≥2%亚组,T2信号强度比<2%亚组;早期强化率值≥3.51%亚组,早期强化率<3.51%亚组。ROC分析结果显示,在T1弛豫时间≥1310.5 ms亚组、T2信号强度比≥2%亚组、早期强化率值≥3.51%亚组中T1弛豫时间、T2信号强度比、早期强化率值诊断急性心肌炎的价值较好,AUC分别为0.979、0.959、0.999。结论定量CMR参数诊断急性心肌炎均具有一定价值,对定量CMR参数进行增量划分后其诊断急性心肌炎价值更高。

基于工作适应理论的民航机务维修人员职业价值观激励研究

民航机务维修人员是守护航空器“健康”的核心,是保证飞行安全的“最后一道闸”。组织应当如何满足员工的价值诉求,如何提升机务维修人员的职业满意度以及如何有效避免不安全事件的发生,已成为新时代民航业高质量发展重点关注的问题。本研究以民航机务维修人员为研究对象,基于工作适应理论,从安全管理的角度设计民航机务维修人员职业价值观的初始量表,对11家机场和航空公司的1500名机务维修人员进行问卷测试,通过因子分析方法得出影响机务维修人员职业价值观的关键要素,从工作适应理论的组织需求和个体需求两个方面提出激励策略,为机务维修人员安全绩效的提升以及民航的高质量发展提供有效的理论支撑和政策建议。

基于改进GM(1,1)模型的变电站检修运维费用预测

针对变电站因设备的缺陷而引起的全寿命周期成本(life cycle cost,LCC)中检修运维费用拨付波动现象,分别采用传统的灰色GM(1,1)模型和组合改进的灰色GM(1,1)模型,对未来3年地市A的变电站检修运维费用进行预测,优化现有的成本拨付策略。结果表明,2种模型的预测精度等级均为一级,但改进后模型的平均相对误差及后验差比值均低于传统模型,说明改进模型比传统模型具有更高的预测精度,能够更好地预测变电站的检修运维费用。最后,利用改进的预测模型对某地市A的2019—2021年变电站检修运维费用进行预测。

考虑拆卸结构的动车组系统动态机会维修策略

为研究拆卸结构对动车组系统维修计划的影响,运用拆卸混合图模型分析单部件最优拆卸序列。并基于效费比分析方法选择多级维修方式,计算考虑拆卸成本和安装调试成本的部件最优可靠度阈值。在此基础上,引入机会维修理念,针对系统内多部件维修前拆卸序列规划问题,提出多拆卸目标序列优化方法,建立考虑可靠度价值浪费的动态机会维修策略模型。算例分析表明,动态机会维修策略相较于传统顺序预防性维修策略,通过归并维修时机,停机次数减少16次,有效减少因预防性维修和拆卸时间冗长造成的停机成本损耗,且维修总成本节省16.6%,满足维修部门对经济性的要求,为动车组系统考虑复杂相关性的维修策略研究提供理论支持。

东北天然次生针阔混交林乔木层碳储量变化的采伐干扰响应

[目的]探究采伐干扰对东北典型天然次生针阔混交林乔木层碳储量变化的影响,为东北地区森林可持续经营提供理论依据。[方法]在吉林省林业实验区国有林保护中心选取4块1 hm^(2)针阔混交林样地,2011年开展初次调查,同年冬季进行采伐作业,2013、2015、2018和2021年复测保留木。采用双变量线性回归法,探讨采伐强度、物种多样性、功能多样性、系统发育多样性和群落加权平均性状值对碳储量和碳增量的影响;使用多元线性回归模型,比较各变量的贡献程度;利用结构方程模型,检验各变量对碳储量和碳增量的直接和间接效应。[结果]1)碳储量和碳增量多元线性回归模型中,采伐强度对碳储量和碳增量的贡献分别占总解释量的25%和5%;植物物种多样性对碳储量和碳增量的贡献分别占总解释量(物种、功能、系统发育多样性)的67%和58%;群落加权平均性状值对碳储量和碳增量的贡献分别占总解释量的8%和37%。2)碳储量结构方程模型中,采伐强度对系统发育多样性、功能多样性、最大树高加权性状值和碳储量具有显著负向效应,路径系数分别为−0.221、−0.454、−0.337和−0.229;采伐强度对木质密度加权性状值具有显著正向效应,路径系数为0.368;采伐强度对物种多样性的直接效应不显著;物种多样性和功能多样性对碳储量具有显著正向效应,路径系数分别为0.306和0.235;系统发育多样性和群落加权平均值对碳储量的直接效应不显著。3)碳增量结构方程模型中,最大树高加权性状值对碳增量具有显著正向效应,功能多样性与木质密度加权性状值不相关,其他变量间的关系与碳储量模型相同。[结论]物种多样性、功能多样性、群落加权平均性状值对碳储量和碳增量具有直接影响,森林经营时可通过增加植物种类以促成功能多样的林分来提高森林碳汇能力。采伐强度直接或间接通过功能多样性和群落加权平均性状值减少碳储量和碳增量,在森林经营中应合理采伐,以提高森林碳汇能力。

面向销售数据的多项缺失值关联性的增量填补

数据缺失会影响数据的质量,可能导致分析结果的不准确和降低模型的可靠性,缺失值填补能减低偏差方便后续分析.大多数的缺失值填补算法,都是假设多项缺失值之间是弱相关甚至无相关,很少考虑缺失值之间的相关性以及填补顺序.在销售领域中对缺失值进行独立填补,会减少缺失值信息的利用,从而对缺失值填补的准确度造成较大的影响.针对以上问题,本文以销售领域为研究目标,根据销售行为的多维度特征,利用不同模型输出值的空间分布特征特性,探索多项缺失值的填补更新机制,研究面向销售数据多项缺失值增量填补方法,根据特征相关性,对缺失特征排序并用已填补的数据作为信息要素融合对后面的缺失值进行增量填补.该算法同时考虑了模型的泛化性和缺失数据之间的信息相关问题,并结合多模型融合,对多项缺失值进行有效填补.最后基于真实连锁药店销售数据集通过大量实验对比验证了所提算法的有效性.

计及指标重要度的地铁供电设备健康状态分级评估方法

针对现有维修模式中存在的“维修不足”和“维修过度”等问题,提出了一种计及指标重要度的地铁供电设备健康状态分级评估方法。根据层次分析和模糊统计相结合的方法求解设备健康值,并将指标的重要度考虑在内,对设备所处的健康状态进行等级划分,最后以干式变压器为例进行实例分析。研究结果表明:利用本文提出的评估方法能够合理地表征地铁供电设备的健康状态,与实际情况符合,验证了方法的准确性及可行性。

TyG指数、血清CCL18及骨硬化蛋白对维持性血液透析并发心血管事件的预测价值

目的 探讨甘油三酯葡萄糖(TyG)指数、血清趋化因子配体18(CCL18)及骨硬化蛋白(SOST)对维持性血液透析并发心血管事件的预测价值。方法 选取2019年1月至2021年1月潍坊市人民医院收治的100例维持性血液透析患者,随访2年,根据是否并发心血管事件分为并发心血管事件组(n=30)和未并发心血管事件组(n=70),另选取50名同期来本院体检的健康者作为对照组。对比3组受检者TyG指数、CCL18及SOST表达水平,采用Spearman相关性分析对TyG指数、CCL18及SOST与维持性血液透析并发心血管事件的相关性进行分析。随后进行维持性血液透析并发心血管事件的单因素分析,并将其纳入多因素Logistic回归模型,分析血液透析并发心血管事件的独立影响因素。最后分析TyG指数、CCL18联合SOST检测的预测价值。结果 3组受检者TyG指数、CCL18联合SOST表达水平对比差异显著,并发心血管事件组患者的TyG指数、CCL18及SOST表达水平分别为9.46±2.46、(89.80±13.82) ng/mL、(121.27±13.35) pmol/L,均明显高于未并发心血管事件组[9.46±2.46、(89.80±13.82) ng/mL、(121.27±13.35) pmol/L]和对照组[9.46±2.46、(89.80±13.82) ng/mL、(121.27±13.35) pmol/L],差异均有统计学意义(P<0.05)。Spearman相关分析结果显示:TyG指数、CCL18及SOST与维持性血液透析并发心血管事件呈正相关(P<0.05)。单因素分析结果显示,TyG指数、CCL18、SOST、合并高血脂、合并高血压、合并糖尿病、吸烟史、高磷血症、透析时间是维持性血液透析并发心血管事件的危险因素(P<0.05)。进一步行多因素Logiscic回归分析结果显示,TyG指数、CCL18、SOST、合并高血脂、合并高血压、合并糖尿病、高磷血症是维持性血液透析并发心血管事件的独立危险因素(P<0.05)。TyG指数、CCL18联合SOST预测维持性血液透析并发心血管事件的敏感度和特异度达到94.24%和85.72%,曲线下面积值为0.892。结论 TyG指数、CCL18及SOST水平升高为维持性血液透析并发心血管事件的独立影响因素,且三者联合检测可对维持性血液透析并发心血管事件的发生进行可靠预测。

递增式抗阻运动联合营养治疗应用于接受维持性血液透析治疗的终末期肾脏病患者效果分析

目的评价递增式抗阻运动联合营养治疗应用于接受维持性血液透析(MHD)治疗的终末期肾脏病(ESRD)患者的效果。方法本研究为回顾性分析,选取2023年1月至2023年6月在唐山中心医院接受MHD治疗的ESRD患者120例,按照随机数字表法将其分为3组,即对照组(常规治疗)、营养治疗组(营养治疗)和营养运动组(递增式抗阻运动联合营养治疗),每组各40例。评价治疗6个月后3组的人体测量指标[身高、体重、体重指数、肱三头肌皮褶厚度(TSF)、上臂中围(MAC)、上臂肌围(MAMC)、营养指标(血红蛋白、前白蛋白和转铁蛋白)、主观综合性营养评估法(SGA)评分、6 min步行试验(6MWT)、“坐-立”体位试验(STS 10)]、生活质量[简明健康状况调查表(SF-36)]及不良事件发生情况等,并进行统计比较。结果营养运动组体重指数、TSF、MAC和MAMC分别为(23.29±2.34)kg/m^(2)、(12.56±1.88)mm、(26.37±2.20)cm、(22.42±2.01)cm,均明显高于对照组[(20.03±2.16)kg/m^(2)、(9.74±1.81)mm、(22.10±2.04)cm、(19.04±1.88)cm]和营养治疗组[(21.14±2.51)kg/m^(2)、(10.17±1.80)mm、(23.89±2.31)cm、(20.70±1.96)cm],差异均有统计学意义(P<0.05)。营养运动组血红蛋白、前白蛋白、转铁蛋白水平分别为(105.59±16.46)g/L、(311.44±80.36)mg/L、(1.85±0.31)g/L,均明显高于对照组[(91.14±18.23)g/L、(247.01±77.35)mg/L、(1.55±0.29)g/L]和营养治疗组[(97.79±15.80)g/L、(271.44±81.16)mg/L、(1.70±0.32)g/L],SGA评分为(9.01±1.54)分,明显低于对照组[(12.60±4.98)分]和营养治疗组[(11.24±1.71)分],差异均有统计学意义(P<0.05)。营养运动组6MWT和握力分别为(420.61±82.35)m、(28.48±3.93)kg,均明显高于对照组[(362.75±72.87)m、(16.59±4.11)kg]和营养治疗组[(377.08±79.53)m、(19.04±4.29)kg],STS 10为(22.17±2.03)s,明显低于对照组[(25.29±2.40)s]和营养治疗组[(23.95±2.26)s],差异均有统计学意义(P<0.05)。营养运动组SF-36量表评分为(77.05±9.10)分,明显高于对照组[(61.81±7.79)分]和营养治疗组[(71.36±8.82)分],差异均有统计学意义(P<0.05)。营养治疗组和营养运动组总不良事件发生率为15.00%、7.50%,显著低于对照组(42.50%),营养运动组低血压发生率为2.50%,显著低于对照组(17.50%),差异均有统计学意义(P<0.05),营养治疗组和营养运动组不良事件发生率比较差异均无统计学意义(P>0.05)。结论递增式抗阻运动联合营养治疗可有效改善接受MHD治疗的ESRD患者的营养状况、躯体功能和生活质量,减少不良事件的发生。