Manufacturing production plan optimization in three-stage supply chains under Bass model market effects

The Bass model is a very successful parametric approach to forecast the diffusion process of new products. In recent years, applications of the Bass model have been extended to other operational research fields such as managing customer demands, controlling inventory levels, optimizing advertisement strategies, and so forth. This study attempts to establish an application for optimizing manufacturers’ production plans in a three-stage supply chain under the Bass model’s effects on the market. The supply chain structure considered in this research is similar to other common supply chains comprised of three stages, namely retailer, distributor and manufacturer. The retailer stage has to handle customer demands following the Bass diffusion process. Market parameters and essential information are assumed to be available and ready for access. Each stage is expected to determine its inventory policy rationally. That is, each stage will attempt to maximize its own profits. These decisions will back-propagate their effects to upper stages. This study adopts a dynamic programming approach to determine the inventory policies of each stage so as to optimize manufacturers’ production plans.     

电网转型背景下地市级智能电网示范区规划研究

在南方电网公司向智能电网运营商、能源产业价值链整合商、能源生态系统服务商转型的背景下,贵阳智能电网示范区面临着巨大的机遇和挑战。以南方电网公司安全、可靠、绿色、高效的智能电网发展总体要求为指引,结合贵阳市经济社会发展需求,研究贵阳智能电网示范区规划方案。提出了更加安全可靠、更加智能高效、更加规范统一、更加减量增益的贵阳智能电网示范区总体目标,明确了近期（2019-2020年）和远期（2021-2025年）两步走的智能电网示范区发展路线,提出了提高城市电网供电可靠性、提升农网供电能力、加强智能技术应用、推动大数据应用、提升智能用电水平、开展综合能源服务等6项重点任务、19项重点工作,以期全面建成贵阳智能电网示范区,进一步提升服务经济社会发展的能力。     

土地利用/土地覆盖遥感变化检测方法新进展

土地利用/土地覆盖变化检测是资源环境研究中的一个重要方面,准确、及时的变化信息为人类资源环境的生产和管理提供了决策支持。遥感技术具有实时、快速、覆盖范围广、多光谱、周期性等特点,给土地利用/土地覆盖变化检测提供了理想的数据基础。人类社会的发展对土地利用/土地覆盖变化检测的精度与效率不断提出新的要求,这也使得一些新技术、新方法引入到变化检测中。这些新技术新方法提高了土地利用/土地覆盖变化检测的精度,但在效率方面有待进一步研究。     

基于约束规划的最优浇次计划模型研究

基于约束规划提出最优连铸浇次计划模型.模型在以往研究的基础上增加了板坯厚度约束和交货期约束;为不同钢级赋予不同的量化值,按照组浇工艺要求规定的钢级范围来确定能够组成同一浇次的钢级量化允许值范围,将组浇工艺要求直接量化;模型不仅确定浇次的组成,而且确定浇次的顺序和炉次在浇次内的顺序.根据生产实际随机生成数据所做的实验表明所提出的方法是有效的.     

基于树型门控循环单元的基数和代价估计器

基数估计和代价估计可以引导执行计划的选择,估计准确性对查询优化器至关重要.然而,传统数据库的代价和基数估计技术无法提供准确的估计,因为现有技术没有考虑多个表之间的相关性.将人工智能技术应用于数据库(artificial intelligence for databases, AI4DB)近期得到广泛关注,研究结果表明,基于学习的估计方法优于传统方法.然而,现有基于学习的方法仍然存在不足:首先,大部分的方法只能估计基数,但忽略了代价估计;其次,这些方法只能处理一些简单的查询语句,对于多表查询、嵌套查询等复杂查询则无能为力;同时,对字符串类型的值也很难处理.为了解决上述问题,提出了一种基于树型门控循环单元, Tree-GRU (tree-gated recurrent unit)的基数和代价估计方法,可以同时对基数和代价进行估计.此外,采用了有效的特征提取和编码技术,在特征提取中兼顾查询和执行计划,将特征嵌入到Tree-GRU中.对于字符串类型的值,使用神经网络自动提取子串与整串的关系,并进行字符串嵌入,从而使具有稀疏性的字符串变得容易被估计器处理.在JOB、Synthetic等数据集上进...     

Correction to Schneider and Logan (2006).

Reports an error in "Hierarchical Control of Cognitive Processes: Switching Tasks in Sequences" by Darryl W. Schneider and Gordon D. Logan (Journal of Experimental Psychology: General, 2006[Nov], Vol 135[4], 623-640). Two task transitions were classified incorrectly in Table 7 (p. 634). The task transition at Serial Position 1 for sequence switches of the AABB sequence should be TR instead of TS. The task transition at Serial Position 1 for sequence switches of the ABBA sequence should be TS instead of TR. Two sections of text in the Results and Discussion section of Experiment 4 were affected by the misclassifications. The corrected text is provided for the Error rate analysis section (pp. 634-635) and the RT analysis section (p.635). These corrections do not alter any of the conclusions drawn from the original text. (The following abstract of the original article appeared in record 2006-20327-009.) Hierarchical control of cognitive processes was studied by examining the relationship between sequence- and task-level processing in the performance of explicit, memorized task sequences. In 4 experiments, switch costs in task-switching performance were perturbed by sequence initiation times that varied with sequence complexity, preparation time, and type of sequence transition (repetition or switch). Hierarchical control was inferred from these sequence initiation time effects and the recurrent finding of no switch cost at the first serial position across sequences, the point at which sequence-level processes are likely active in maintaining or instantiating a hierarchical control structure in working memory. These findings resonate with past research on motor programs and serial memory and provide new insights into the concepts of task set and control. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analysis of time-series MODIS 250 m vegetation index data for crop classification in the U.S. Central Great Plains

The global environmental change research community requires improved and up-to-date land use/land cover (LULC) datasets at regional to global scales to support a variety of science and policy applications. Considerable strides have been made to improve large-area LULC datasets, but little emphasis has been placed on thematically detailed crop mapping, despite the considerable influence of management activities in the cropland sector on various environmental processes and the economy. Time-series MODIS 250 m Vegetation Index (VI) datasets hold considerable promise for large-area crop mapping in an agriculturally intensive region such as the U.S. Central Great Plains, given their global coverage, intermediate spatial resolution, high temporal resolution (16-day composite period), and cost-free status. However, the specific spectral-temporal information contained in these data has yet to be thoroughly explored and their applicability for large-area crop-related LULC classification is relatively unknown. The objective of this research was to investigate the general applicability of the time-series MODIS 250 m Enhanced Vegetation Index (EVI) and Normalized Difference Vegetation Index (NDVI) datasets for crop-related LULC classification in this region. A combination of graphical and statistical analyses were performed on a 12-month time-series of MODIS EVI and NDVI data from more than 2000 cropped field sites across the U.S. state of Kansas. Both MODIS VI datasets were found to have sufficient spatial, spectral, and temporal resolutions to detect unique multi-temporal signatures for each of the region's major crop types (alfalfa, corn, sorghum, soybeans, and winter wheat) and management practices (double crop, fallow, and irrigation). Each crop's multi-temporal VI signature was consistent with its general phenological characteristics and most crop classes were spectrally separable at some point during the growing season. Regional intra-class VI signature variations were found for some crops across Kansas that reflected the state's climate and planting time differences. The multi-temporal EVI and NDVI data tracked similar seasonal responses for all crops and were highly correlated across the growing season. However, differences between EVI and NDVI responses were most pronounced during the senescence phase of the growing season.     

计算机虚拟现实技术在消防数字预案中的应用

在我国现行的消防数字预案系统中,由于缺乏必要的技术改进,消防安全重点单位消防预案大多是纯文字和图表的,消防官兵通过阅读预案只能得到一个模糊的概念,无法更精确的分析,因而逐渐暴露出一些难以解决的问题.在这种情况下,计算机技术的发展,特别是近年来计算机虚拟现实技术的研究与开发,为消防数字预案系统的更新发展提供了一个良好的契机.     

关于VPN技术和应用

随着计算机网络日益深入人们的日常生活和工作,人们已经不仅仅局限于独立地使用内部专用网络和公共互联网络,而是要利用Internet技术建立自己的内部网.本文介绍了VPN的分类,VPN的特性,涉及的隧道技术、加密、解密技术、认证系统和PPTP协议、L2TP协议、IPSec协议等技术,以及VPN在实际运用中的解决方案和优缺点.     

Recognizing the agent''s goals incrementally:planning graph as a basis

Plan recognition, the inverse problem of plan synthesis, is important wherever a system is expected to produce a kind of cooperative or competitive behavior. Most plan recognizers, however, suffer the problem of acquisition and hand-coding a larger plan library. This paper is aims to show that modern planning techniques can help build plan recognition systems without suffering such problems. Specifically, we show that the planning graph, which is an important component of the classical planning system Graph-plan, can be used as an implicit, dynamic planning library to represent actions, plans and goals. We also show that modern plan generating technology can be used to find valid plans in this framework. In this sense, this method can be regarded as a bridge that connects these two research fields. Empirical and theoretical results also show that the method is efficient and scalable.