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61.
基于摆线运动的黄瓜采摘机器人终端滑模轨迹跟踪控制   总被引:3,自引:1,他引:2  
黄瓜采摘机器人是机器人技术在农业中的具体应用,而快速稳定地到达目标采摘点的轨迹规划则是黄瓜采摘机器人研究的主要内容之一。根据摆线运动曲线光滑,并能在有限区间的端点产生零速度和零加速度的特点,将其应用于黄瓜采摘机器人关节空间的轨迹规划,该方法计算简单,实时性好。同时,为了实现对期望轨迹的精确跟踪,构造了一种快速非奇异的终端滑模控制器,采用指数和幂次结合的趋近率方法,引入非线性滑模面,突破了普通滑模控制器在线性滑模条件下渐进收敛的特点,并且不会出现传统终端滑模控制的奇异性和抖振问题。李亚普诺夫稳定性分析和仿真试验证明:它能够准确的跟踪期望轨迹,并能使位置跟踪误差在有限时间内收敛到零,响应时间短,跟踪效果好。  相似文献   
62.
Individual animals undergoing ontogenetic shifts in habitat use may establish a mobile link between discrete ecosystems via movement of energy, nutrients and matter, as well as through impacts on ecosystem and habitat structure. The American Alligator (Alligator mississippiensis) is a model species for studying ecological implications of ontogenetic niche shifts, because they grow in size by several orders of magnitude, and they play a critical role as both top predators and ecosystem engineers. We used equal trapping effort, radio telemetry and nest surveys to document ontogenetic habitat shifts of alligators between hydrologically isolated, seasonal wetlands and riverine systems. To estimate the degree of functional connectivity between systems, we quantified alligator biomass and nutrient excretion in both systems. Seasonal wetlands provided nesting and nursery sites for adult females and juveniles, which constituted 0.78 g/m2 biomass and excreted 0.05 g/m2/yr N, P, Ca, Mg, Na and K in that system. In contrast, the riverine system provided non-nesting habitat for adults and sub-adults of both sexes, totaling 0.18 g/m2 biomass and excreting 0.01 g/m2/yr of nutrients. Furthermore, sub-adults and adult females were documented moving across the terrestrial matrix, while adult males spent the duration of the study in the creek. Our results demonstrated that ontogenetic niche shifts in alligators establish connectivity between seasonal wetlands and riverine systems and with the surrounding terrestrial matrix. These findings have implications for the definition of jurisdictional wetlands under the US Supreme Court’s 2001 SWANCC decision and highlight the importance of ecological, as well as hydrological, connectivity.  相似文献   
63.
集装箱码头分派车辆的整数规划模型   总被引:1,自引:0,他引:1  
建立了一个用于确定集装箱码头一组车辆工作次序的整数规划模型,其中这组车辆是用于把从货仓起重机卸下的集装箱运输到码头的存贮位置。证明了求解这一整数规划模型等价于求解n个车辆安排线路问题的几条路径,并设计了前向搜索算法(FSA)和后向搜索算法(BSA)两种启发式算法,用于确定集装箱码头大型货轮卸货车辆的可行分派方案。  相似文献   
64.
管小卫  丁琳 《安徽农业科学》2011,39(33):20893-20895
通过对多个农产品提供商的调研,提出基于.NET平台的农产品移动库存管理系统设计思想。介绍了系统开发的相关技术、结构和功能设计、数据库设计,并论述了系统开发中数据同步技术和通信安全技术等关键技术。  相似文献   
65.
Precision agricultural maps are required for agricultural machinery navigation, path planning and plantation supervision. In this work we present a Simultaneous Localization and Mapping (SLAM) algorithm solved by an Extended Information Filter (EIF) for agricultural environments (olive groves). The SLAM algorithm is implemented on an unmanned non-holonomic car-like mobile robot. The map of the environment is based on the detection of olive stems from the plantation. The olive stems are acquired by means of both: a range sensor laser and a monocular vision system. A support vector machine (SVM) is implemented on the vision system to detect olive stems on the images acquired from the environment. Also, the SLAM algorithm has an optimization criterion associated with it. This optimization criterion is based on the correction of the SLAM system state vector using only the most meaningful stems - from an estimation convergence perspective - extracted from the environment information without compromising the estimation consistency. The optimization criterion, its demonstration and experimental results within real agricultural environments showing the performance of our proposal are also included in this work.  相似文献   
66.
Documentation is a major component of any traceability system where traceability is defined in the ISO Regulation 8402:1994 as the ability to trace the history, application and location of what is under consideration. Traceability systems are record keeping systems designed to track the flow of product or product attributes through the production process or supply chain. All international supply chains are forced to comply with traceability requirements. In this paper, we develop and implement an end-to-end mobile application prototype that traces the poultry production. This application consists of front-end and back-end systems. At the front-end, the worker uses a GPRS enabled handheld device (cell phone, PDA, etc.) to capture information on poultry operations collected at a remote chicken farm and transmit it to a back-end server in the main office. Through customized application the back-end server analyses all information received from the front-end and based on a built-in business process and business rules, intelligently updates various stakeholders of any breach of bio-security measures that requires immediate attention. The proposed system administrators can also access this application via Internet for management decision making. The back-end system consists of web server, defined business application logic and database server.  相似文献   
67.
以Hort16A猕猴桃(Actinidia chinensis Planch.)顶芽为外植体,研究了不同植物生长调节剂组合对丛生芽诱导、生根培养的影响。结果表明,在丛生芽诱导培养中,培养基中生长调节剂最适浓度组合为6-BA 1 mg/L与NAA 0.03 mg/L,丛生芽的诱导率到达92%,芽的长势较好。生根培养中,在1/2MS培养基中生长调节剂IBA最适浓度为0.5 mg/L,生根率到达了98%。  相似文献   
68.
基于Web GIS以及移动GIS技术,建立了浦东新区农用地内外一体化核查平台,实现前台信息采集上报、后台数据核实统计、野外核查的一体化、网络化使用功能,旨在为新区农用地的信息化管理、农业生产统计和涉农补贴发放提供科学依据和方法。  相似文献   
69.
The female sex hormone estrogen exerts anti‐inflammatory effects. The G‐protein‐coupled estrogen receptor (GPER) has been recently identified as a novel membrane‐type estrogen receptor that can mediate non‐genomic estrogenic effects on many cell types. We previously demonstrated that GPER inhibits tumor necrosis factor alpha‐induced expression of interleukin 6 (IL‐6) through repression of nuclear factor‐kappa B (NF‐κB) promoter activity using human breast cancer cells. Although several reports have indicated that GPER suppresses Toll‐like receptor‐induced inflammatory cytokine expression in macrophages, the molecular mechanisms of the inhibition of cytokine production via GPER remain poorly understood. In the present study, we examined GPER‐mediated inhibition of IL‐6 expression induced by lipopolysaccharide (LPS) stimulation in a mouse macrophage cell line. We found that the GPER agonist G‐1 inhibited LPS‐induced IL‐6 expression in macrophage cells, and this inhibition was due to the repression of NF‐κB promoter activity by GPER. G‐1 treatment also decreased the phosphorylation of inhibitor of κB kinases. Among the mitogen‐activated protein kinases, the phosphorylation of c‐jun N‐terminal kinase (JNK) was increased by G‐1. These findings delineate the novel mechanism of the inhibition of LPS‐induced IL‐6 through GPER‐activated JNK‐mediated negative regulation of the NF‐κB pathway in murine macrophage cells, which links anti‐inflammatory effects to estrogen.  相似文献   
70.
基于无线和短信环境安全型猪舍监控技术研究   总被引:2,自引:0,他引:2  
通过无线和短信结合,实现了对环境安全型猪舍的监控。系统由无线智能传感器、无线或短信通信终端、监控中心和执行节点四部分组成,采用集散控制方法。监控中心是整个系统的核心,对数据进行集中管理、分析和处理,其他部分负责数据采集、传输和执行。  相似文献   
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