Comprehensive Evaluation of Distributed PV Grid-Connected Based on Combined Weighting Weights and TOPSIS-RSR Method

To effectively quantify the impact of distributed photovoltaic(PV)access on the distribution network,this paper proposes a comprehensive evaluation method of distributed PV grid connection combining subjective and objective combination of assignment and technique for order preference by similarity to an ideal solution(TOPSIS)—rank sum ratio(RSR)(TOPSIS-RSR)method.Based on the traditional distribution network evaluation system,a comprehensive evaluation system has been constructed.It fully considers the new development requirements of distributed PV access on the environmental friendliness and absorptive capacity of the distribution grid and comprehensively reflects the impact of distributed PV grid connection.The analytic hierarchy process(AHP)was used to determine the subjective weights of the primary indicators,and the Spearman consistency test was combined to determine the weights of the secondary indicators based on three objective assignment methods.The subjective and objective combination weights of each assessment indicator were calculated through the principle of minimum entropy.Calculate the distance between the indicators to be evaluated and the positive and negative ideal solutions,the relative closeness ranking,and qualitative binning by TOPSIS-RSR method to obtain the comprehensive evaluation results of different scenarios.By setting up different PV grid-connected scenarios and utilizing the IEEE33 node simulation algorithm,the correctness and effectiveness of the proposed subject-object combination assignment and integrated assessment method are verified.

Application of Leading-Subject Teaching Method in Class Teaching of Landscape Type of Public Elective Course

For concrete situation of class teaching of landscape type of public elective course,the application situation of leading-subject teaching method in specific landscape type of course is explored. Teaching method transforms from "teaching as the center" to "learning as the center". By improving student's learning interest and efficiency,student's whole development and creativity are promoted.

Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in Henan Province,China

Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter wheat.Therefore,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly important.This study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in Henan Province as the basic data for predicting winter wheat yield.Using the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was calcu-lated.The estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)models.Finally,the determined optimal yield estimation method was used to predict winter wheat yield in three typical years.Following are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other algorithms.The best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe drought.Compared with severe drought year(2011)(R^(2)=0.680)and normal year(2017)(R^(2)=0.790),the SSA-RF model has higher prediction accuracy for wet year(2018)(R^(2)=0.820).This study could provide an innovative approach for remote sensing estimation of winter wheat yield.yield.

Research on seismic performance and design method of combined steel lead energy dissipation structure(Ⅰ)

A new combined steel lead damper (NCSLD) was presented. Construction and working mechanism of NCSLD were introduced,pseudo-static tests of the small size dampers which would be used in the subsequent shaking table tests were carried out for the study of mechanical properties of NCSLD using electro-hydraulic servo press-shear machine. Processing technology of the damper was improved. Shaking table tests under two-dimensional excitation on structural aseismic control of a one-story structure model were carried out using the small size NCSLD; parameters of the structure and shaking table were also introduced. Results indicate that process improvement is beneficial to the implementation of working mechanism of the damper,NCSLD has full hysteresis loop which takes on bilinearity,NCSLD has obvious energy dissipation effect and it can control structural seismic response effectively.

Optimization of steel casting feeding system based on BP neural network and genetic algorithm

The trial-and-error method is widely used for the current optimization of the steel casting feeding system, which is highly random, subjective and thus ineff icient. In the present work, both the theoretical and the experimental research on the modeling and optimization methods of the process are studied. An approximate alternative model is established based on the Back Propagation(BP) neural network and experimental design. The process parameters of the feeding system are taken as the input, the volumes of shrinkage cavities and porosities calculated by simulation are simultaneously taken as the output. Thus, a mathematical model is established by the BP neural network to combine the input variables with the output response. Then, this model is optimized by the nonlinear optimization function of the genetic algorithm. Finally, a feeding system optimization of a steel traveling wheel is conducted. No shrinkage cavities and porosities are induced through the optimization. Compared to the initial design scheme, the process yield is increased by 4.1% and the volume of the riser is decreased by 5.48×10~6 mm3.

Optimization of measurement distance of (109)~Cd K XRF system for obese subjects

The precision of results obtained from the ^109Cd K XRF in vivo measurement system of bone lead for obses subjects with high BMI( body mass index)was poor.The main factor affecting the precision was the distance between tibia and detector.Compared with the standard phantom,a large phantom was used to simulate the obese subject in the measurements at different distances to the detector.The counts of Compton scattering increased highly because of the tissue overlying and surrounding tibia of the obese subject.When the distance between leg and detector was too small,the instrument would produce the distorted X-ray spectra,so that the obtained data were inaccurate,In order to ensure good measuremtn precision and accuracy,the distance between leg and detector should be maintained at 25mm during the counting period.Meanwhile,the dead time displayed instantly on the instrument should be controlled to around 30%.

Remediation Technology for Combined Pollution of Lead and Cadmium in Farmland Soil

At present,the problem of heavy metal pollution in farmland in southern China is serious. Especially,the cadmium and lead are two heavy metal elements with serious pollution and great harm to human body. This paper reviewed some common methods and materials used in the control of cadmium and lead pollution in farmland soil. Then,it discussed the problems in the repair of cadmium and lead pollution in farmland soil. It came up with the future research direction,to provide references for remediation of lead and cadmium pollution in farmland soil.

习近平文化思想的哲学阐释

习近平文化思想是习近平新时代中国特色社会主义思想的重要组成部分,是新时代中国共产党领导文化建设实践经验的理论概括和科学总结。习近平文化思想深刻体现了新时代中国共产党人文化主体性的守正创新,以“两个结合”为深厚底蕴,坚持民族性与世界性相融通,将“魂脉”与“根脉”相结合,在认识论、历史观和辩证法层面实现了对马克思主义哲学的时代创新。习近平文化思想正面回应了西方文明的现代性困境,聚焦西方现代文明的自反性问题和价值异化倾向,提出构建人类命运共同体与创造人类文明新形态的科学论断。习近平文化思想坚持守正与创新相结合、坚持主体性与多样性相融汇、坚持理论与实践相贯通,在实践中深化了对中国特色社会主义文化建设规律的深刻认识,展现了习近平文化思想蕴含的哲学意蕴,必将在新时代中国特色社会主义文化建设中展现思想伟力,在担当新时代新的文化使命中彰显马克思主义的真理力量。

道阻且长,“行”者将“治”:公共事务的行为治理之道

行为治理是将行为科学洞见应用于公共治理场域而发展出的治理新模式。行为治理关注政府、组织和公民三类核心治理主体在互动过程中的心理、认知及行为规律,并分析治理主体互动关系的元素特征如何影响主体行为,同时更全面地考虑环境因素对微观行为的影响,以及个体行为汇聚为集体行动并产生更广泛治理结果的机制。行为治理呼吁治理工具的组合运用,强调“助推”和“助力”两大行为工具的内部融通,重视行为工具与传统工具的外部联动。行为治理脱胎于行为公共管理和行为公共政策,更强调各主体间的互动性,更重视环境的复杂性,更主张治理工具在内外部及各层次上的融会贯通。行为治理紧扣治理主体的行为要素,自下而上、从微观到宏观,丰富国家治理现代化的思想库和工具箱。

中华文化主体性的总体性呈现

中华文化主体性是深刻理解习近平文化思想作为强大思想武器和科学行动指南的核心概念,要从更悠远的历史纵深、更宽阔的时代视野、更美好的未来图景的协调贯通中加以总体性呈现。中华文化主体性以中华历史文化传统为立基之本,以铸牢中华民族共同体意识为现实关注,以中华优秀传统文化“接着讲”为核心命题,由此确立了本土化定位的基本依据。中华文化主体性意味着中国式现代化在打破“现代化=西方化”的迷思中确立了高度的主体自觉,在深化“第二个结合”的理解中坚定了强烈的文化自信,在推进全体人民精神富有的历程中找准了明确的价值目标,由此明确了现代化追求的内生动力。中华文化主体性渗透着世界文明交流互鉴的根本原则,蕴含着建设中华民族现代文明的世界意义,彰显着人类文明新形态的光明前景,由此展现了全球化发展的开放胸怀。中华文化主体性是新时代中国特色社会主义文化建设实现传统赓续发展、精神独立自主和文明交流互鉴三方面贯通融合、有机统一的充分彰显。

盐碱地水肥耦合对基质栽培番茄生长与产量品质的影响

为探究盐碱地水肥耦合对基质栽培番茄生长的影响,设置3组灌溉水平W1(268 mm),W2(201 mm),W3(161 mm)和3组施肥水平(N-P_(2)O_(2)-K_(2)O,kg/hm^(2))F1(260-200-220 kg/hm^(2)),F2(208-160-176 kg/hm^(2)),F3(156-120-132 kg/hm^(2)),共9组耦合处理,以无基质水肥组合作为对照组CK,基于温室大棚试验研究水肥耦合对盐碱地土壤盐分、基质栽培番茄株高茎粗、根系特征、产量与品质的影响,并构建遗传算法多目标优化模型确定盐碱地基质栽培番茄的最优水肥调控策略.结果表明:与CK相比,基质处理株高、茎粗、根系特征、水肥利用效率、产量与品质具有显著优势;基质处理土壤表层盐分含量较低,土壤剖面0~30 cm表现为积盐过程,30~60 cm表现为脱盐过程;通过AHP-CRITIC主客观组合赋权的VIKOR法对番茄产量、风味品质进行评价,处理W3F1的利益比率最小,产量与品质最佳;基于遗传算法多目标优化模型求解Pareto最优解,确定盐碱地基质栽培番茄的最佳水肥耦合策略为W3F2,研究可为盐碱地高品质果蔬的水肥科学管理提供理论依据.

中国式现代化与文化主体性建构

文化主体性是跨文化视域中民族文化自我意识的集中彰显,是文化自信的根本依托,展现了面向民族文化的整体图景。历史和现实揭示,中国式现代化同文化主体性建构具有深刻关联。一方面,中国的现代化践履塑造着文化主体性:在封建社会中文化主体性以文化基本精神的潜在形式呈现,中国共产党对现代化的探索历程使中华文化主体性实现了从内隐到外显的变革,同时在拓展叙事空间的意义上将文化主体性建构推向新的高度。另一方面,文化主体性给中国式现代化提供了能动力量:文化主体性强化着中国式现代化探索的自我意识,夯实着中国式现代化的文化根基,同时赋予中国式现代化鲜明的中国特色。在行动策略上,新时代继续推进文化主体性建构必须深刻认识中国式现代化和文化主体性同向而行的关系,坚持高质量发展、推进中国式现代化,以丰富文化主体性所展开的经济社会基础;深化“第二个结合”,推进中华优秀传统文化的创造性转化和创新性发展,创造彰显文化主体性的中国式现代化的文化形态。

教育强国建设的多维起点、内涵意蕴与主体行动

建设教育强国是中华民族伟大复兴的基础工程。新时代,加快建设教育强国,需要从中国建成世界规模最大教育体系、中华优秀传统文化基因和中国教育发展的主要矛盾方面准确把握教育强国的多维起点。需要从本体论、功能论、语境论分析教育强国的内涵。需要利益相关主体协同发力,办学主体要提升支持力,加强资源保障;行政主体要提升决策力,增强政策供给;校长要提升领导力,优化学校运行;教师要提升教育力,增值专业资本;学生要提升学习力,培养发展活力。

习近平文化思想的实践指向

习近平文化思想遵循马克思主义“现实的个人”、物质生产是全部社会生活的基础以及人民群众是精神文化创造主体的原理,以人民性作为本质属性,巩固了中华文化主体性;高度重视“两个结合”是探索中国特色社会主义道路的规律性认识,围绕社会主义精神文化建设,把中华文明的智慧结晶同马克思主义相结合,创造了新的文化生命体;作为一个开放的、不断发展的思想体系,推进文明交流互鉴,告别故步自封,把中华文化不断推向世界,增强中华文化传播力影响力;把握文化建设规律,夯实马克思主义中国化时代化的文化根基和群众基础,担负起新的文化使命,建设中华民族现代文明,彰显历史唯物主义实践旨归。

地铁列车牵引系统状态评估方法研究

充分挖掘现场故障统计数据,提出一种地铁列车牵引系统状态评估方法。首先基于牵引系统故障树建立层次分析模型,构建各层级评判矩阵并确定权重,然后计算牵引系统各模块基本事件的灰色聚类系数,完成对系统模块层的状态评估,最后利用各模块聚类系数构建牵引系统模糊综合评判矩阵,采用模糊综合评判法对牵引系统整体的健康状态进行评估。结果表明,牵引逆变模块和牵引控制单元板卡是该车型地铁列车牵引系统的薄弱环节,应作为检修与维护中的重点对象。该评估方法综合利用故障树—层次分析法确定权重,降低了人为因素的影响,其评估结果可为地铁列车牵引系统主动维护和检修提供有效依据。

中国文化现代转型的唯物辩证法意蕴

中国文化现代转型是中国文化发展的历史必然,也是推进中国式现代化的内在要求。从转型的动力看,近代以来中国对现代性文化的需要,构成了中国文化现代转型的动力。从转型的方向看,发展葆有中华民族文化特性的社会主义现代性文化是在中国文化发展过程中逐步明确的。从转型的过程看,中国式现代化文化形态经由历史的中国文化否定之否定而形成。从转型的方式看,“两个结合”,特别是“第二个结合”,体现了中国共产党对中国文化现代转型对立统一规律的深刻把握。从转型的原则看,坚持和巩固中国文化主体性,防止文化转型走向极端,是对质量互变规律适度原则的坚持。唯物辩证法视角的审视为深度理解把握中国文化现代转型提供了科学方法。

土壤铅砷交互作用对花生体内铅和砷迁移转运的影响

铅(Pb)、砷(As)在我国受重金属污染的农田土壤中往往同时存在,研究其交互作用对作物体内Pb、As迁移转运的影响对于重金属超标农田安全利用具有重要指导意义。采用盆栽试验,探究了不同浓度梯度Pb(70、120 mg·kg^(-1))、As(40、100 mg·kg^(-1))两两组合处理下(CK、Pb70、Pb120、As40、As100、Pb70+As40、Pb70+As100、Pb120+As40、Pb120+As100),花生对Pb、As的富集转运特征。结果表明:与单一污染相比,低浓度As(As40)的存在对低浓度Pb(Pb70)处理下花生不同部位Pb含量无显著影响,但使得高浓度Pb(Pb120)处理下籽粒Pb含量降低17.6%,Pb总富集量无显著变化;高浓度As(As100)的存在显著降低了两个Pb浓度处理下花生各部位Pb含量以及Pb总富集量;复合污染下Pb从根系、茎叶、壳向籽粒的转运能力均下降。Pb70的存在使As40处理下花生茎叶As含量升高了18.2%,其他部位无显著影响,As总富集量升高了18.8%,显著提高了As100处理下花生各部位As含量以及As总富集量。Pb120的存在显著提高了两个As浓度处理下花生各部位As含量以及As总富集量;复合污染下As从根系、茎叶、壳向籽粒的转运能力均增强。总的来说,复合污染增加了籽粒中As超标风险,降低了Pb超标风险。土壤全量和有效态Pb或As含量均与花生各部位Pb或As含量以及总富集量呈极显著的正相关关系,同时土壤全量和有效态As含量与籽粒Pb含量表现为显著负相关,而土壤全量和有效态Pb含量与籽粒As含量无显著相关性。

具有前缘凹凸结构的组合翼型优化设计及其气动特性分析

为了不断探索翼型改型的方法和提高翼型的气动性能,将传统翼型与生物翼型进行轮廓修型设计得到组合翼型,通过数值模拟的方法对组合翼型进行气动特性分析.同时,对组合翼型进行前缘凹凸结构优化设计,采用正交试验优选出气动特性表现最优的参数,并对最优前缘组合翼型进行气动特性分析.研究发现:相比标准NACA64-618翼型,组合翼型在小范围攻角有着较高的升力系数,升力系数最大提高了7.3%,此外,具有前缘凹凸结构的前缘组合翼型升阻比最大提高了9.98%.组合翼型的弯度前移使得吸力面负压峰值区域面积增大,翼型上下表面压差增大,进而提高了气动性能;前缘组合翼型由于前缘凹凸结构的存在,在翼型吸力面靠近尾缘处,形成一对反向旋涡,增加了流体在翼型表面覆盖的面积,抑制了流动分离的提前发生,进而达到失速延迟的效能.

农业龙头企业认定资格取消对企业经营的影响

发展农业产业化经营,是促进农业结构战略性调整,提高农业综合效益,实现农业现代化的有效措施。以农业龙头企业为研究对象,基于2011—2021年的面板数据,运用固定效应模型分析龙头企业认定资格取消和存续时间对龙头企业经营的影响。结果表明:龙头企业认定资格取消对龙头企业经营产生了不利影响;龙头企业存续时间增加对龙头企业经营产生了积极影响;认定资格取消与存续时间对龙头企业经营的影响存在地区和规模显著差异;研发创新水平和企业社会责任在认定资格取消影响龙头企业经营中具有调节效应。据此提出完善龙头企业认定标准、合理配置资等建议,以期实现龙头企业高质量发展,使其在名单中不断存续。

基于XGBoost和组合权重方法的桂林市野火灾害风险性评估

野火灾害风险性评估工作可以定量评估野火灾害对社会经济和自然生态造成损失的风险。以桂林市为研究区,以2017—2021年的历史野火数据为基础。首先,基于XGBoost算法结合所选取的15项评价因子进行野火易发性分析。其次,对选取的8项灾害易损性因子利用主客观组合权重法对野火易损性进行评估。最后,基于所构建的易发和易损性评估模型,开展桂林市野火灾害风险性评估分析。结果表明:(1)野火易发性模型AUC为0.993,预测准确率为0.9698,表明该易发性预测模型拥有优秀的预测性能,气温、高程、坡度和风速因子是影响野火灾害发生的最重要因素;(2)野火灾害易损性评估结果与客观事实相符合,具有良好的可信度;(3)桂林市野火灾害风险性评价结果与桂林市的野火灾害的空间发生概率和社会承灾能力吻合程度高,验证了所提模型的可行性和有效性,为桂林市灾害管理部门的防灾减灾提供了决策支持。