Forecasting daily potential evapotranspiration using machine learning and limited climatic data

Anticipating, or forecasting near-term irrigation demands is a requirement for improved management of conveyance and delivery systems. The most important component of a forecasting regime for irrigation is a simple, yet reliable, approach for forecasting crop water demands, which in this paper is represented by the reference or potential evapotranspiration (ET_o). In most cases, weather data in the area is limited to a reduced number of variables measured, therefore current or future ET_o estimation is restricted. This paper summarizes the results of testing of two proposed forecasting ET_o schemes under the mentioned conditions. The first or “direct” approach involved forecasting ET_o using historically computed ET_o values. The second or “indirect” approach involved forecasting the required weather parameters for the ET_o calculation based on historical data and then computing ET_o. An statistical machine learning algorithm, the Multivariate Relevance Vector Machine (MVRVM) is applied to both of the forecastings schemes. The general ET_o model used is the 1985 Hargreaves Equation which requires only minimum and maximum daily air temperatures and is thus well suited to regions lacking more comprehensive climatic data. The utility and practicality of the forecasting methodology is demonstrated with an application to an irrigation project in Central Utah. To determine the advantage and suitability of the applied algorithm, another learning machine, the Multilayer Perceptron (MLP), is used for comparison purposes. The robustness and stability of the proposed schemes are tested by the application of the bootstrap analysis.     

基于行动导向的《数控加工工艺与手工编程》课程开发

从基于行动导向课程开发基础流程、相关概念及行动领域分析-情境设计-课程实施等几个方面介绍了《数控加工工艺与手工编程》课程的开发,对《数控加工工艺与手工编程》课程教学如何实现基于工作过程导向的教学改革进行了探索与实践。     

广东省典型农作物智能专家分类系统设计与示范应用

在广东省科技计划项目支持下,在广东省典型农作物标准波谱数据库中设计了符合典型农作物的长势监测和种植面积测算功能模块,将数据挖掘和知识发现应用到专家分类算法中,自行开发了适合农作物数据发现和挖掘的归纳学习算法,充分利用了波谱库中大量的波谱数据、相关属性和空间数据,形成了基于波谱库的广东省典型农作物智能专家分类系统。同时,进行了深圳市的荔枝面积估算的示范研究,结果显示分类精度达到91.8%,KAPPA达到0.81,高于传统分类算法,能满足农业部门对农情监测的要求。     

榆树市玉米宽窄行倒茬平作耕作模式的研究分析及其关键配套机具的探讨

榆树是全省农业机械化重点县(市).文章通过阐述榆树市玉米宽窄行倒茬平作耕作模式、播种方式及深松追肥、对土壤生态属性的影响,分析并探讨榆树市玉米宽窄行倒茬平作耕作模式及关有玉米收割机配套选型的注意事项.     

Spatio-temporal channel assignment in multi-radio wireless mesh networks

A method of spatio-temporal channel assignment based on graph decomposition was proposed to solve the ripple effect and link failure problem in multi-radio wireless mesh networks. Network topology was decomposed into subgraphs in several time slots to extend channel assignment from spatial domain to time domain. Then, graph coloring algorithm was used to optimize the channel assignment on the basis of the subgraph in each time slot. Each subgraph obtained channel resource dynamically according to the network constraints to improve the channel assignment efficiency. Simulation results show that, compared to static channel assignment scheme, the impact of negative factors, such as the ripple effect and link failure caused by channel switching, are effectively confined with this strategy. The network throughput is increased at least by 30% while satisfying the constraints on the number of radios and the number of network channels.     

Training young horses to social separation: effect of a companion horse on training efficiency

Reasons for performing study: The intensity with which a horse responds to separation from its group and subsequently to being alone is relevant for both horse and handler safety. Identification of training methods that may reduce responses to separation would be useful in practice. Objectives: To investigate whether the initial presence of a familiar companion horse modifies responses to separation from the group, lowers stress levels (as measured by heart rate) and increases training efficiency. Hypothesis: Habituation to separation proceeds more quickly if the horse is first trained with a companion, and heart rate is lower when the horse is subsequently trained alone, compared to control horses trained individually from the start. Methods: Young mares (n = 32), kept in groups of 4 were exposed to social separation: 2 horses of the group were trained singly (S1, n = 16) and the remaining 2 horses (n = 16) were trained first with a companion (P2) and then alone (P1). The training comprised 3 steps whereby distance from the group was gradually increased. The final learning criterion was met when a horse fed calmly alone inside a test arena (Step 3). Horses that were trained in a pair had to succeed in Step 3 together before they repeated the steps alone. Feeding behaviour and heart rate were recorded. Results: There were no significant differences between S1 and P1 horses, indicating that the initial pair‐training did not reduce responses in P1 horses. However, heart rate was significantly lower when horses were trained in pairs (P2) compared to when the same horses were subsequently trained alone (P1). Conclusions and potential relevance: It may not be efficient to habituate naïve young horses to social separation initially with a partner as these horses appear to have to relearn being in the test situation alone when switching to the individual training.     

Layout about Motion of Robot basedon Ant Algorithm

Over the last few years, ant algorithm has come out and gradually got much attention.This algorithm, which is stochastic and all purpose, simulates the characteristics of action ants searching for food in nature. When working, a mobile robotis required to walk along an optimized (or approximately optimized) route according to a certain rule.By maklink graph, the moving space of Robot is described.Using Ford algorithm,a preliminary route is gained.Then, exerting Ant algorithm, we optimize the preliminaryroute and acquiresatisfactory effect.     

冬虫夏草深层发酵的研究

通过时冬虫夏草菌（ＣｏｒｄｙｃｅｐｓＳｉｎｅｎｓｉｓ）的深层发酵条件如ｐＨ、培养温度、接种量及转速的探讨及对深层发酵培养基碳氮源和无机盐的筛选，确定了其深层培养所需条件及最佳碳氮源和无机盐。实验结果表明：冬虫夏草菌深层发酵的最适培养条件应为２４℃、２００ｒ／ｍｉｎ、ｐＨ５．０左右，接种量５～１５％，菌丝生长的最佳碳源为葡萄糖，最佳氮源为蛋白和氨基酸复合粉，最佳无机盐为磷酸二氢钾、硫酸镁和氯化钙。     

辣椒深加工产品中辣素含量的测定

本文简述了辣椒油树脂、晶体状辣素产品中辣素及其组成成分的含量测定的各种方法；获得了数百个测定结果；提出了统一辣素测定方法的建议。