Disassemblability Modeling Technology of Configurable Product Based on Disassembly Constraint Relation Weighted Design Structure Matrix(DSM)

The current research of configurable product disassemblability focuses on disassemblability evaluation and disassembly sequence planning. Little work has been done on quantitative analysis of configurable product disassemblability. The disassemblability modeling technology for configurable product based on disassembly constraint relation weighted design structure matrix （DSM） is proposed. Major factors affecting the disassemblability of configurable product are analyzed, and the disassembling degrees between components in configurable product are obtained by calculating disassembly entropies such as joint type, joint quantity, disassembly path, disassembly accessibility and material compatibility. The disassembly constraint relation weighted DSM of configurable product is constructed and configuration modules are formed by matrix decomposition and tearing operations. The disassembly constraint relation in configuration modules is strong coupling, and the disassembly constraint relation between modules is weak coupling, and the disassemblability configuration model is constructed based on configuration module. Finally, taking a hydraulic forging press as an example, the decomposed weak coupling components are used as configuration modules alone, components with a strong coupling are aggregated into configuration modules, and the disassembly sequence of components inside configuration modules is optimized by tearing operation. A disassemblability configuration model of the hydraulic forging press is constructed. By researching the disassemblability modeling technology of product configuration design based on disassembly constraint relation weighted DSM, the disassembly property in maintenance, recycling and reuse of configurable product are optimized.

Bounded Hankel Products on the Weighted Bergman Space

1 Introduction The Bergman space Aα^2 is the space of analytic functions on a plane domain D which are square integrable with respect to the measure.

Fabrication scheduling on a single machine to minimize the weighted sum of product completion time

In this paper, a fabrication scheduling problem concerning the production of components at a single manufacturing facility was studied, in which the manufactured components are subsequently assembled into a finite number of end products. Each product was assumed to comprise a common component to all jobs and a unique component to itself. Common operations were processed in batches and each batch required a setup time. A product is completed when both its two operations have been processed and are available. The optimality criterion considered was the minimization of weighted flow time. For this scheduling problem, the optimal schedules were described in a weignted shortest processing time first （WSPT） order and two algorithms were constructed corresponding to the batch availability and item availability, respectively.

基于weighted slope one用户聚类的林产品推荐算法

随着电商平台用户、林产品数量规模不断扩大,协同过滤推荐时构建的用户-林产品评分矩阵变得高维稀疏,导致推荐算法精度和可扩展度下降。基于此本文提出一种weighted slope one用户聚类推荐算法,将其应用在林业产品个性化推荐服务中。首先,通过weighted slope one算法的思想填充高维稀疏的用户-林产品评分矩阵;其次,使用Kmeans聚类算法对用户进行聚类,产生相似用户集合,缩小推荐过程中邻居用户的搜索范围;最后,在大数据Mahout平台进行实际推荐,为林产品贸易平台个性化推荐服务的大规模实现奠定基础。经仿真实验表明,文中提出的算法能够全面提升推荐的精度和可扩展性。

Almost sure central limit theory for products of sums of partial sums

Consider a sequence of i.i.d.positive random variables.An universal result in almost sure limit theorem for products of sums of partial sums is established.We will show that the almost sure limit theorem holds under a fairly general condition on the weight dk= k-1 exp（lnβk）,0≤β〈1.And in a sense,our results have reached the optimal form.

Revisiting acute liver injury associated with herbalife products

In the November 27,2010 issue of the World Journal of Hepatology (WJH),three case reports were published which involved patients who had consumed various dietary supplements and conventional foods generally marketed as weight loss products.The reference to Herbalife products as contaminated and generally com-parable to all dietary supplements or weight loss prod-ucts is not scientifically supported.The authors provided an insufficient amount of information regarding patient histories,concomitant medications and other com-pounds,dechallenge results,and product specifications and usage.This information is necessary to fully assess the association of Herbalife products in the WJH case reports.Therefore,the article does not objectively sup-port a causal relationship between the reported cases of liver injury and Herbalife products or ingredients.

Utilization of Vegetable Waste Juice by Purple Non-Sulfur Bacterium (Afifella marina Strain ME) for Biomass Production

This experiment was conducted to determine the possibility of utilization of vegetable waste juice in the production of purple non-sulfur bacterium Afifella marina biomass. Bacterium was cultured in four diluted such as, 10%, 20%, 30% and 40% (v/v) vegetable waste juices. In addition synthetic 112 media were used as control to compare the growth characteristics of Afifella marine. The bacterium Afifella marina grew well in 10% diluted vegetable waste juice in anaerobic light condition with the highest production of 5.02 g/l dry cell weight in fifth day of culture, whereas the highest total carotenoid production of 0.87 mg/g dry cell weight was recorded in third day of culture. The highest dry cell weight productions recorded in 10% of VWJ was significantly higher compared to four other treatments (F = 14.63;p = 0.00). However, the total carotenoid production of bacteria in 10% VWJ showed no significant difference compared to the carotenoid production in 112 synthetic media, but was significantly higher compared to three other treatments (P = 0.00). The bacterium, Afifella marina has the ability to use vegetable waste juice at certain level for the production of bacterial biomass.

“双碳”背景下主产区粮食生产减污降碳综合效益评价

基于2002—2021年中国13个粮食主产区的面板数据,采用熵权TOPSIS法、障碍因子诊断模型与Dagum基尼系数,实证分析主产区粮食生产减污降碳综合效益及其时空演化。结果表明:2002—2021年粮食主产区综合效益指数由0.388提高至0.878,整体为上升态势;主产区综合效益水平呈现“东高西低”的空间分布特征;核心障碍因素存在由粮食产出效率与粮食产出水平向粮食生产投入集约化水平与粮食生产碳排放强度集中的转变过程;总体差异水平未出现进一步缓解的趋势,空间差异主要来源于区域间差异,样本期贡献率均值为56.89%,东西部间差异最大,东部、中部地区区域内的基尼系数水平也存在上升趋势,说明缓解区域内差异同样不容忽视。据此,建议切实提高资源投入集约化程度,统筹协调各区域综合效益均衡发展,建立绿色粮食生产体系,强化绿色低碳收益,进而实现农业高质量发展。

Application of Mixed Group Decision Making to Safety Evaluation of Agricultural Products

In view of the gravity of issues concerning safety of agricultural products and urgency of resolving these issues,after analyzing the problems existing in safety of agricultural products,this article offers a method for evaluating safety of agricultural products on the basis of mixed group decision making.First of all,it introduces the factors influencing safety evaluation of agricultural products;subsequently,given that the judgment matrices offered by the group of experts contain both reciprocal and complementary judgment matrices in the process of jointly participating in evaluation arising from personal preference,it proposes to assemble expert information in order to obtain indicator weight using the OWA operator;finally,the process of evaluating safety of agricultural products is given.

基于帝国竞争反向传播神经网络的断块油田开发顺序优化

明确断块油田群中断块的开发顺序是进行开发方案设计的前提条件。断块油田数量较少时,可以进行技术经济的组合对比,但是断块数量较多时会形成海量的组合,耗费时间也长。断块油田开发顺序评价的现有方法有权重评价法、层次分析法、综合模糊评判法等,这些方法在选择评价指标和指标权重上带有较强的主观性,无法做到完全客观的评价。因此本文提出一种基于帝国竞争算法改进的反向传播神经网络模型,首先采用Spearman相关系数法确定影响断块油田开发的主控因素,其次使用分段三次Hermite插值方法实现断块油田群开发数据库的扩充,最后在扩充后的大量数据库训练样本的基础上,基于帝国竞争算法改进的反向传播神经网络模型可以确定影响开发效果参数的权重并预测断块油田群中各断块油田的净现值,根据净现值大小可以确定每个断块的开发顺序。该方法以实际断块油田群的地质油藏数据库作为评价依据,断块油田的开发顺序更加的科学合理,项目整体的净现值也明显高于依靠传统方法确定的开发顺序组合,避免了人为主观性,也节省了数值模拟和经济评价的工作量,克服了现有方法的局限性,对于提高断块油田群开发综合效益具有重要意义。

基于熵权TOPSIS法的河北省农产品电商物流服务能力评价及对策研究

完善的农村电商物流体系是实现乡村振兴战略、促进农村经济发展的重要举措,文章通过构建河北省农产品电商物流能力指标体系,用熵权TOPSIS法对河北省农产品电商物流服务能力进行实证分析。结果表明:河北农村电商发展环境有待进一步优化,农产品电商服务能力仍有待提升。针对河北农产品电商物流信息化、人才培养、市场营销和农产品标准化等方面问题提出解决对策,研究内容对河北省农村经济发展、农产品物流良性发展具有指导意义。

福建省农业生产力发展评价与结构优化行动研究——基于熵权TOPSIS模型

为科学测度地区农业生产力发展水平,优化农业产业结构布局,促进地区经济发展和乡村振兴。从农业生产功能、农业价值功能两个维度和生产资源与条件、生产水平和能力、农业结构、产值、市场竞争力等5个方面28个指标构建了福建省农业生产力水平评价指标体系,并采用熵权TOPSIS模型对福建省9个地市的农业生产力发展水平进行评价。结果表明:(1)从权重分配来看,大部分指标对农业生产力发展的影响较大,特别是农业价值功能指标方面;(2)从综合评价方面看,具有先天资源优势的闽西北地区和具有后天发展潜力的闽南地区的综合发展水平比较好;(3)从子系统评价和聚类分析看,指标分异比较明显的地区主要有厦门、莆田、泉州、漳州、南平和三明,分异较小的有福州、宁德和龙岩。福建省9个地市的农业生产力发展水平差异比较大,且具有板块化特征,特别是功能指标表现特征明显。针对以上问题,提出了闽西北绿色农业产业“保粮保生态”行动、闽南高优农业产业“多元增效”行动、闽东北山海协作产业“挖潜增效”行动,建议以“圈”状格局、人与自然和谐、闽台农业融合等方面优化产业布局,提升福建省农业生产力发展水平。

中国茶叶生产格局变迁及其影响因素研究

基于1985—2021年中国茶叶生产面板数据,采用GIS空间分析、多尺度地理加权回归模型探究中国茶叶生产格局的时空演变特征及影响因素。结果表明:(1)1985—2021年,中国茶叶生产规模不断扩大,生产重心持续“西移”,空间集聚存在显著正向规模效应,江南、华南和西南茶区聚集特征以“高高”型和“低高”型聚集为主,江北茶区未出现集聚特征,空间极化现象突出。(2)不同时期影响中国茶叶生产格局变迁的主导因素存在显著差异。1995年以有效灌溉面积和化肥投入量为主,2010年降水量、日照时数、受灾面积的影响程度逐步凸显,2020年后交通运输水平成为显著驱动因素,但是有效灌溉始终是影响茶叶生产格局变迁的主要驱动力。

中国发展方式绿色转型的统计测度及时空演进分析

加快发展方式绿色转型,是贯彻落实新发展理念的战略要求,是践行绿色发展理念的时代命题。评估中国发展方式绿色转型进程,对于实现“双碳”目标、推动经济社会高质量发展具有重要现实意义。本文采用熵权法,选取2011~2022年我国30个省(区、市)的面板数据,对各省(区、市)发展方式绿色转型水平进行测度并分析其时空演变特征和地区差异。研究发现:(1)中国发展方式绿色转型进程取得了阶段性成果,东部地区发展方式绿色转型程度最高;(2)东部地区与其他三大地理区域的发展方式绿色转型水平差异显著,其中东部地区与东北地区的差异最大;(3)发展方式绿色转型是一个渐进式过程,存在稳定的β收敛特征。研究结论对于缩小地区间发展方式绿色转型差异、加快发展方式绿色转型进程具有参考意义。

河北省农产品国际竞争力评价及影响因素研究

发展农产品贸易,提升农产品国际竞争力对促进河北省农业高质量发展具有重要意义。以2006—2020年河北省农产品生产需求等相关数据为依据,采用熵权法构建农产品国际竞争力综合评价指标体系,研究了河北省农产品国际竞争力水平及发展趋势,并综合运用双钻石模型,从国际国内2个层面探究河北省农产品国际竞争力的影响因素,以期为全省农产品国际竞争力提升提供参考依据。结果表明:河北省农产品国际竞争力呈现稳步增长态势,农产品全球指标与国内指标走势基本一致,规模以上农副食品加工业R&D人员和沿海港口货物吞吐总量对竞争力的影响较大。

多向加权Tsallis熵最大化导向的自动阈值分割方法

受噪声或随机细节、目标和背景的大小比例、成像时的点扩散等不同因素的影响,许多图像的灰度直方图呈现为无模态、单模态、双模态或者多模态样式.为了在统一框架内处理这4种不同模态情形下的自动阈值选择问题,本文提出了一种多向加权Tsallis熵最大化导向的自动阈值分割方法(Multi-directional Weighted Tsallis Entropy,MWTE).基于新设计的反正切方向性卷积核的多尺度乘积效应,该方法将不同模态的灰度直方图转化为统一的单模态右偏灰度直方图.在4个不同方向上提取出这种特殊的单模态右偏灰度直方图后,通过多向加权策略构建出与原始图像灰度值紧密相关的加权Tsallis熵目标函数,并以该目标函数取最大值时对应的灰度值作为最终分割阈值.本文将提出的方法和3个阈值分割方法、1个软分割方法、1个活动轮廓分割方法以及1个自动聚类分割方法进行了比较.在4种不同模态情形下的4幅合成图像和50幅真实世界图像上的实验结果表明,本文提出的方法虽然在计算效率方面不占有优势,但它对不同模态的测试图像具有更稳健的分割适应性,且在量化分割精度所用的马修斯相关系数方面优于其他6个分割方法.

基于BP神经网络的海底浅层超软黏土不排水抗剪强度预测

准确评估海底浅层超软黏土的不排水抗剪强度对海洋资源开发、灾害评估、海洋工程建设等具有重要的意义。世界多个海域超软黏土数据分析对比表明,现有不排水抗剪强度评估经验公式存在受地域限制的问题,计算精度较低。因此,以超软黏土的6个物性指标为输入变量,不排水抗剪强度为输出变量,建立BP神经网络模型进行海底浅层超软黏土不排水抗剪强度预测;根据建立的超软黏土不排水抗剪强度与物性指标之间的非线性映射网络,以权积法求解超软黏土不排水抗剪强度对各指标的敏感度系数,定量分析各指标对不排水抗剪强度的影响程度。结果表明:考虑多因素影响的BP神经网络模型在超软黏土不排水抗剪强度预测方面具有普遍适应性,其预测结果非常接近落锥试验实测结果,均方差0.02139,R2值达到0.9874,预测精度远高于现有经验公式;采用权积法计算得到的对数流动性指标对不排水抗剪强度最为敏感;据此建立了以对数流动性指标为参数的黏土不排水抗剪强度预测经验公式,该公式在计算中国海域超软黏土不排水剪切强度方面具有较高精度,但由于数据量有限,依旧存在一定局限性。本研究为海底浅层超软黏土不排水抗剪强度的计算提供了参考。

新质生产力水平测度与区域时空差异

作为高质量发展与中国式现代化的必然要求,新质生产力的测度对区域差异及未来发展方向具有重要意义。本文建立评价指标体系,利用2012—2020年面板数据测度新质生产力发展综合水平,并分析区域差距的时空演化,研究发现:新质生产力总体水平较低,培育与成熟阶段水平变化呈“稳定—上升”的波动趋势;东部与东北地区区域内变化趋势与全国变化趋势同步,中西部地区存在明显滞后效应;东部地区与其余三大区域间差距很大,空间集聚效应明显,东部地区实力遥遥领先。进一步研究发现,创新力与竞争力是新质生产力总体水平的关键障碍因素,滞后效应导致各区域关键障碍因素存在异质性,跨区域合作机制能够充分利用空间集聚效应。

工艺参数对微结构注塑制品重量和复制精度的影响

微结构注塑制品的重量重复精度及微结构复制精度是衡量微结构注塑制品成型质量的重要指标。通过实验研究了熔体温度、模具温度、注射压力、保压压力和保压时间等重要工艺参数对制品重量及微结构复制精度的影响。实验结果表明,各个工艺参数均对微结构注塑制品存在不同程度的影响,熔体温度和注射压力是影响制品重量的主要因素,保压时间是影响微结构复制精度的主要因素。当熔体温度从270℃增大至310℃时,制品平均重量从4.9406 g提高到5.4431 g,当注射压力从110 MPa增大至150 MPa时,制品重量重复精度从1.6494%提高到0.1240%,当保压时间从5 s增大至8 s时,微结构复制精度从89.771%提高至96.188%。

基于生命周期法的生鲜农产品冷链物流绿色度评价

随着国家节能减排政策的深入,生鲜冷链作为能耗较高的物流产业,其绿色性引起了人们的重视。文章基于生鲜农产品冷链物流的全生命周期分析其各阶段的绿色性,以各阶段碳排放量和资源利用率为指标建立绿色度评价体系,并以番茄为例,基于生命周期法的计算数值,采用熵权法进行权重计算,进而用灰色关联度法进行绿色度评价。评价结果表明,生鲜农产品运输过程的损耗是对绿色度影响最大的因素,其次是车辆的能源利用率和货物的实载率。另外,水路运输的碳排放量远低于公路运输,但受限于地理条件和运输时间。针对评价结果,给出了提高生鲜农产品冷链物流绿色度的建议,为减少碳排放量提供了改进方向。