A method for Improving the Efficiency of Pear Tree Crossbreeding

In view of the short blooming period of pear tree crossbreeding and the complexity of pollination process, a method that can improve the efficiency of crossbreeding of pear trees was provided. Meanwhile, this method can also be applied to the study of pollen xenia effect, pollination tree selection and pure pollen collection in pear tree cultivation.

基于Cross-efficiency DEA的中间站运营绩效分析

根据传统DEA存在的局限性,在有关文献研究的基础上,提出了基于Cross-efficiency DEA模型的中间站绩效分析方法,在调查收集影响中间站运营绩效基础数据的基础上,利用灰色关联分析法提取了评价指标体系,采用Cross-efficiency DEA模型对中间站运营绩效进行了分析、评价和测算,并运用MATLAB软件编程进行了求解,获得了各中间站源配置效率的排序,在对非DEA有效的决策单元进行投影分析的基础上,识别出影响决策单元运营绩效的关键因素,为改进非DEA有效决策单元提供了一个可行方案。最后利用实例验证了该模型的有效性、科学性,分析结果表明:Cross-efficiency DEA模型基本能够反映决策单元运行效率的现实状况。

基于Cross-efficiency DEA算法的区域科技资源配置效率测算研究

伴随信息化水平的日益提高,我国科技资源组织结构和运行效率进一步优化。然而由于我国区域经济发展的非均衡性问题,导致了我国科技资源配置的区域差异性。本文引入Cross-efficiency DEA算法,从科技资源投入、产出的视角对我国30个省、市、自治区对应的科技资源配置效率进行了测算。利用Cross-efficiency在群体综合评价中能够完全排序的优点,可以获得区域资源配置效率的排序结果,从而为区域科技管理提供有效的参考信息。

Guide Vane with Current Plate to Improve Efficiency of Cross Flow Turbine

To get the sustainable society, the hydropower with not only the large but also the small/mini/micro capacities has been paid attention to in the power generation. The cross flow turbine can work effectively at the comparatively low head and/or low discharge, then the runner and the turbine profile has been optimizing. In this paper, the model turbine was prepared in accordance with the traditional design, and the performance and the flow condition were investigated experimentally at the various operating conditions. The hydraulic efficiency is doubtlessly maximal while the guide vane is at the normal/design position, and deteriorates in the lower discharges adjusted by the guide vane. Such deteriorations are brought from the unacceptable flow conditions in the inlet nozzle. To improve the efficiency dramatically in the lower discharge, the guide vane installed in the inlet nozzle was equipped with the current plate, and the fruitful effects of the plate on the efficiency were confirmed experimentally.

Ranking approach of cross-efficiency based on improved TOPSIS technique

The cross-efficiency evaluation method is reviewed which is developed as a data envelopment analysis （DEA） extensive tool. The cross-efficiency evaluation method is utilized to identify the decision making unit （DMU） with the best practice and to rank the DMUs by their respective cross-efficiency scores. The main drawbacks of the cross-efficiency evaluation method when the ultimate average cross-efficiency scores are used to evalu- ate and rank the DMUs are also pointed out. With the research gap, an improved technique for order preference by similarity to ideal solution （TOPSIS） is introduced to rank the crossfficiency by eliminating the average assumption. Finally, an empirical example is illustrated to examine the validity of the proposed method.

Promoting Balance in Output Efficiencies for Cross-Efficiency Evaluation in Data Envelopment Analysis

Cross-efficiency evaluation is recognized as an effective way of efficiency assessment for a set of decision making units (DMUs) in the framework of data envelopment analysis (DEA). It has been generally suggested that secondary goals be introduced for cross-efficiency evaluation owing to the non-uniqueness of optimal solutions in self-evaluation. This paper develops a variety of secondary goals in the spirit of promoting balance in the output efficiencies of the DMU under evaluation. The proposed models attempt to make each output contribute as equally as possible to the self-evaluated efficiency. In this way, the weight flexibility can for one thing be reduced by the introduced secondary goals with selections from alternate optimal solutions, in addition to counting on the dilution of flexibility in the subsequent peer-evaluation. The proposed approach might be applicable to evaluation problems in which multiple outputs are considered important and balance is encouraged to put all dimensions into sufficient use. The effectiveness of the proposed approach and its comparisons with some relevant secondary goals are illustrated empirically using numerical examples.

Cross-efficiency DEA model-based evaluation of allocative efficiency of rural information resources in Jiangsu Province, China

Purpose: This paper aims to compare and rank the allocative efficiency of information resources in rural areas by taking 13 rural areas in Jiangsu Province, China as the research sample.Design/methodology/approach: We designed input and output indicators for allocation of rural information resources and conducted the quantitative evaluation of allocative efficiency of rural information resources based on cross-efficiency model in combination with the classical CCR model in data envelopment analysis(DEA).Findings: Cross-efficiency DEA model can be used for our research with the objective to evaluate quantitatively and objectively whether the allocation of information resources in various rural areas is reasonable and whether the output is commensurate with the input.Research limitations: We have to give up using some indicators because of limited data availability. There is a need to further improve the cross-efficiency DEA model because it cannot identify the specific factors influencing the efficiency of decision-making units(DMUs).Practical implications: The evaluation results will help us understand the present allocative efficiency levels of information resources in various rural areas so as to provide a decisionmaking basis for formulation of the policies aimed at promoting the circulation of information resources in rural areas.Originality/value: Little or no research has been published about the allocative efficiency of rural information resources. The value of this research lies in its focus on studying rural informatization from the perspective of allocative efficiency of rural information resources and in the application of cross-efficiency DEA model to evaluate allocative efficiency of rural information resources as well.

Detection of Mechanical Deformation in Old Aged Power Transformer Using Cross Correlation Co-Efficient Analysis Method

Detection of minor faults in power transformer active part is essential because minor faults may develop and lead to major faults and finally irretrievable damages occur. Sweep Frequency Response Analysis (SFRA) is an effective low-voltage, off-line diagnostic tool used for finding out any possible winding displacement or mechanical deterioration inside the Transformer, due to large electromechanical forces occurring from the fault currents or due to Transformer transportation and relocation. In this method, the frequency response of a transformer is taken both at manufacturing industry and concern site. Then both the response is compared to predict the fault taken place in active part. But in old aged transformers, the primary reference response is unavailable. So Cross Correlation Co-Efficient (CCF) measurement technique can be a vital process for fault detection in these transformers. In this paper, theoretical background of SFRA technique has been elaborated and through several case studies, the effectiveness of CCF parameter for fault detection has been represented.

An Energy-Efficient Access Control Algorithm with Cross-Layer Optimization in Wireless Sensor Networks

This paper presents a wireless sensor network (WSN) access control algorithm designed to minimize WSN node energy consumption. Based on slotted ALOHA protocol, this algorithm incorporates the power control of physical layer, the transmitting probability of medium access control (MAC) layer, and the automatic repeat request (ARQ) of link layer. In this algorithm, a cross-layer optimization is preformed to minimizing the energy consuming per bit. Through theory deducing, the transmitting probability and transmitting power level is determined, and the relationship between energy consuming per bit and throughput per node is provided. Analytical results show that the cross-layer algorithm results in a significant energy savings relative to layered design subject to the same throughput per node, and the energy saving is extraordinary in the low throughput region.

多情景模拟下的跨境铁路运输时效研究——以中老铁路为例

跨境铁路运输是中国与周边国家陆路联通的重要环节。跨境铁路运输时效既受线路畅通情况、基础设施技术等级等“硬联通”因素的制约,也受到海关条例、口岸畅通水平等“软联通”因素的影响。因此,跨境铁路运输时效研究应充分考虑不同情景,以期更科学地模拟运输时长的变化机理。本文以中老铁路(中国昆明−老挝万象,简称中老铁路)为例,在梳理中老铁路沿线地区社会经济概况及基础设施发展水平的基础上,考虑不同运营速度、通关时间、铁轨换装、多式联运等因素,构建了长途跨境运输时间的计算模型,采用多情景模拟方法,解析了中老铁路运的优势距离及客货运时效变化。研究表明:①中老铁路有助于沿线跨境运输时间显著减少。相比公路运输,客货运时间优势均超过20%;②通关时间是影响跨境铁路运输的关键要素之一,占运输总时长的20%~60%;③铁海联运是中老铁路运输进一步提升运输效率的途径,能有效缩短老挝至日本的总运输时间。

学科交叉与融合对大学教学实践的新要求——以“构造地质学”课程教学为例

拓宽学生的知识视野、提高学生对课程知识的兴趣并激发学生的发散性思维是大学教学的重要目的之一。在当前新兴学科和新知识点不断涌现的背景下,学科交叉与融合对大学教学提出了新的要求。以“构造地质学”课程为例,以实例分析该课程的教学内容与旅游地质、生命起源、碳循环和大气成分演变、地球系统科学、行星地质学等新兴学科的密切联系,这种联系要求在大学教学过程中加强课程与新兴学科的交叉和融合,可以通过多种途径实现不同学科的交叉与融合。学科交叉与融合不仅可以拓宽学生的知识视野,而且有助于提高学生学习大学课程的兴趣,激发学生的创造性思维,从而提升教学效果,更好地服务于培养创新型和复合型人才的教学目标。

基于改进分层博弈交叉效率模型的政策评价

政策评估作为政策实施过程中的关键环节,是检验政策效果的基本途径与实现资源优化配置的重要依据.在复杂博弈情境下,决策单元群体间竞合关系不变的假设已经不能满足现实中效率评价的需求,考虑群体间动态变化的合作与竞争关系至关重要.本文将外界冲击下主体间竞合关系演变纳入效率评价框架,提出改进分层博弈交叉数据包络分析方法:从公平的视角出发,基于二次目标模型构建多层次效率矩阵,结合Shapley值对决策单元动态关系演变进行效率评价,进而,以水权交易市场试点政策为例,验证该模型的可行性.该方法放松了政策前后群体竞合关系稳定的假设,验证了水权交易市场政策的有效性和外溢性,为能源与环境领域试点政策效果评价提供了新方法.

不同进水方式对大型水体储热效率的影响

目的针对大型水体跨季节储热时间不匹配问题,分析不同进水方式对储热效率的影响,减少储热过程中的热量损失。方法利用CFD数值模拟软件建立水体储热的分析模型,研究水体储热过程中的热交换规律,以及单双进水口、水平间距、动态进水、流速等因素对水体储热效果的影响。结果进水总流量越小,内部水体温度分层越好;在相同的储热时间内,双进水口方式效率最佳,水体内部平均温度至少比单一进水和动态进水高出16.83%,储热效率分别提高了9.89%和16.14%;相比单一进水口,双进水口方式火用损失降低了21.97%;进水管之间距离越小,水体储热效率越高。结论进水方式对水体储热效率影响至关重要,进水管道越靠近中轴线,采用小流量、双开口的进水形式储热效率越好。

城乡要素市场分割、数字普惠金融与资源配置效率

数字普惠金融作为具有跨地域属性的金融工具在一定程度上能够缓解城乡二元结构对资源有效配置的阻碍。本文采用2009—2018年间的省际面板数据,通过FGLS模型进行实证分析。研究发现:城乡要素市场分割主要通过阻碍农村劳动要素向城镇转移以及城镇资本要素向农村转移等路径抑制资源配置效率的提升;数字普惠金融既具有直接的资源配置效应,又能反向调节城乡要素市场分割对资源配置效率的抑制作用。进一步分析发现,数字普惠金融的调节效应在使用广度、数字支持服务程度以及金融产品协同等子维度均得以明显发挥;同时,该调节效应在基础设施不完善、地区要素禀赋偏资本密集型以及失业率较高时仍然成立。

基于双分支点流语义先验的路面病害分割模型

针对基于深度学习的真实路面病害图像识别算法主要面临的复杂道路背景与病害前景比例不同、病害尺度小等导致的类别严重不平衡、路面病害与道路的几何结构特征对比不明显导致其不易识别等问题,本文提出一种基于双分支语义先验网络,用于指导自注意力骨干特征网络挖掘背景与病害前景的复杂关系,运用高效自注意力机制和互协方差自注意力机制分别对二维空间和特征通道进行语义特征提取,并引入语义局部增强模块提高局部特征聚合能力。本文提出了一种新的稀疏主体点流模块,并与传统特征金字塔网络相结合,进一步缓解路面病害的类别不平衡问题;构建了一个真实场景的道路病害分割数据集,并在该数据集和公开数据集上与多个基线模型进行对比实验,实验结果验证了本模型的有效性。

基于时频域融合和ECA-1DCNN的航空串联故障电弧检测

为了快速准确地检测航空交流线路中出现的串联故障电弧,提出了一种基于时频域融合和加入高效注意力机制(efficient channel attention, ECA)的一维卷积神经网络(one-dimensional convolutional neural network, 1DCNN)的故障检测算法。首先,搭建航空交流电弧故障实验平台,负载选择多类型、多参数值进行电流信号的采集;其次,为了保留更多的故障信息,分析其特征频段,经过大量数据验证,航空串联电弧在发生时,1 000~4 000 Hz分量具有一定的占比,因此将原始信号与特征频段进行融合,融合后的一维数据作为模型输入;最后,搭建ECA-1DCNN检测模型,进行训练,并通过K折交叉验证模型的有效性,得到测试集平均准确率为97.96%。该方法网络层数较少,计算快速,避免了复杂时频域计算过程,较为智能,对航空串联电弧检测装置的研究提供了理论参考。

福建省产学研协同创新效率评价及影响因素分析——基于DEA交叉效率-Tobit模型

利用DEA交叉效率模型测度福建省地级市产学研协同创新效率,以了解福建省各地级市产学研协同创新质量发展差异及存在的问题,并利用Tobit模型深入分析福建省产学研协同创新效率的影响因素,最后提出相应对策与建议。研究发现:2015—2022年福建省9个地级市产学研协同创新效率整体水平不高,呈现“东高西低”空间分布特点,发展不均衡,且不均衡程度有逐渐加重的趋势;经济发展水平对福建省产学研协同创新效率存在显著负向影响,对外开放程度和地方财政科技支出强度存在显著正向影响,而高校(院所)转移知识的能力和企业-高校(院所)合作强度没有产生显著影响。进而提出建议:因地制宜,提升产学研创新资源配置效率;加强合作,强化创新中心城市的创新辐射带动作用;多方引力,提高对外开放水平。

跨媒介阅读效能影响因子实证研究

为研究跨媒介阅读在文本内涵方面的增益或减损,本文在文献梳理和网络调查的基础上,围绕跨媒介阅读与阅读时长、沉浸程度、理解深度、生活联结、感知体验五个变量的关系建立假设、设计问卷、开展调查。利用李克特五级量表,采用回归分析法,确证了跨媒介阅读效能与五个变量之间的正相关性,并呈现递增态势。进一步通过跨媒介阅读比对实验进行验证,分析递增原因,提出维持可持续递增的建议。

跨区域产学协同创新效率测度

在明晰跨区域产学协同创新内涵的基础上,构建跨区域产学协同创新复合协同度模型,通过测算区域间产学协同投入和协同产出表征跨区域产学协同创新主体间的联系,之后基于数据包络方法(DEA)对中国30个省区市的跨区域产学协同创新效率进行测量.研究发现:主要城市群中跨区域产学协同创新的综合效率整体上处于中等水平,京津冀地区的综合效率处于首位,其后依次是长江中游、川渝地区及长三角地区.从省域层面看,综合效率排名前十的省市有天津、山东、河南、广东、宁夏、北京、江西、河北、福建和上海.通过2010年与2018年基于效率临界点的区域划分可知,中国跨区域产学协同创新效率呈现出“双低型”省市数量减少、“双高型”省市数量增加的趋势.深化了跨区域产学协同创新的内涵,有效避免了仅从产出视角评估跨区域产学协同效率时的偏差,对于实现跨区域产学协同创新资源优化配置、推动区域协调发展具有重要意义.

基于熵权网络交叉效率的高校教师绩效评估

为客观有效评估高校教师的科研绩效,促进硬件资源的合理配置,文中综合运用熵权法和网络交叉效率等方法,构建了评价高校教师科研绩效的指标和模型,并使用国内某高校数据进行了实证分析。结果表明,所构建的熵权网络交叉效率模型突破了传统数据包络方法(DEA)对指标数量的限制,避免了人员评价的主观影响。通过交叉效率网络的可视化,实现了任意决策单元间的比较,提高了模型的辨识能力及评价的区分度,可为高校科研管理提供策略依据。