Numerical modeling of chaotic behavior for small-scale movements of demersal fishes in coastal water

ABSTRACT:   The presented model involves the application of chaos theory to generate fish movements resulting from environmental stimuli. The model uses three steps within a model neural network such as input stimuli, central decision making and response output resulting in fish movements. The stimuli in the first step include the main abiotic and biotic factors, which could be quantified as an intensity parameter that was then normalized as a ratio between 0 and 1. The decision-making process can be generated using chaos dynamics with the stimuli parameters. The response of fish movements from the output signal representing movement speed and direction of fish can be re-regulated as main movement pattern depending on physiological state or life cycle by third response filtering. The simulation results seen as a movement pattern for sea bream and flounder using this neural chaotic model fitted very well to the observations of fish tracked in the sea by ultrasonic tracking methods. It was also revealed that the fish movement components generated as movement velocity and direction when in tidal flow had similar patterns to those patterns seen in field observations with similar irregular and chaotic variations with time.     

农业院校产学研协同服务新农村建设的实践与研究-以延边大学农学院为例

从产学研协同的视野出发,结合延边大学农学院的具体实践,从人才培养、科技创新和技术服务等方面探讨了农业院校服务新农村建设的对策,以期为社会主义新农村建设提供人才保障.     

黄河流域典型灌区灌溉节水管理模型研究

以黄河流域上下游2个典型灌区为背景，针对灌区有其农业水管理现状，开发了灌溉节水策略分析决策支持系统（DSS）原型。DSS是一个规划工具，通过对不同策略下田间配水及供水系统的模拟分析及综合决策，寻求最优的策略集合，以达到节约灌溉用水量、提高农业用水效率及维持农业可持续发展的目的。该DSS系统主要用于黄河流域灌区提高农业水管理水平的策略分析，也可用于评估灌区续建配套及土地最佳利用方案等方面。     

基于协同理论产业融合的食用菌电子商务系统构建

基于企业战略协同理论,对食用菌企业协同战略的必要性进行了讨论,介绍了几种食用菌电子商务的模式。在竞争日益激烈的电子商务领域,食用菌行业的电子商务模式也需要战略上的协同与合作,企业在竞争与合作之间要张弛有度、合理控制彼此间的关系,保持自身的核心竞争力,实现合作共赢。     

Research and Application of Decision - making System in Mine Fire

主要介绍了矿井火灾决策系统的组成及应用。矿井火灾决策系统能大大节省灾变时期的反应时间,为企业在第一时间采取果断措施尽可能消除或减少火灾损失争取宝贵的时间,对于矿井火灾的防治具有重要的意义。     

基于WebGIS和知识模型的精确农作决策支持系统

在提炼和优化作物管理知识模型的基础上,以WebGIS为空间信息平台,运用软构件技术及B/S分布式网络结构,构建了网络化精确农作决策支持系统.系统实现了基本地图操作、信息查询、差异分析、决策支持、结果展示以及系统维护功能,其中决策支持功能可基于田区土壤肥力和苗情长势差异进行数字化管理方案生成和因苗动态调控.在水稻试验示范区的系统应用结果表明,根据系统推荐的方案进行水稻田间管理,可使该区整体产量水平提高12.16%,肥料施用量减少23.55%,产量变异度下降79.49%.研究结果为实现网络化、数字化、广适性的精确农作决策支持提供了基本平台.     

Deficit irrigation based on drought tolerance and root signalling in potatoes and tomatoes

Agriculture is a big consumer of fresh water in competition with other sectors of the society. Within the EU-project SAFIR new water-saving irrigation strategies were developed based on pot, semi-field and field experiments with potatoes (Solanum tuberosum L.), fresh tomatoes (Lycopersicon esculentum Mill.) and processing tomatoes as model plants. From the pot and semi-field experiments an ABA production model was developed for potatoes to optimize the ABA signalling; this was obtained by modelling the optimal level of soil drying for ABA production before re-irrigation in a crop growth model. The field irrigation guidelines were developed under temperate (Denmark), Mediterranean (Greece, Italy) and continental (Serbia, China) climatic conditions during summer. The field investigations on processing tomatoes were undertaken only in the Po valley (North Italy) on fine, textured soil. The investigations from several studies showed that gradual soil drying imposed by deficit irrigation (DI) or partial root zone drying irrigation (PRD) induced hydraulic and chemical signals from the root system resulting in partial stomatal closure, an increase in photosynthetic water use efficiency, and a slight reduction in top vegetative growth. Further PRD increased N-mineralization significantly beyond that from DI, causing a stay-green effect late in the growing season. In field potato and tomato experiments the water-saving irrigation strategies DI and PRD were able to save about 20-30% of the water used in fully irrigated plants. PRD increased marketable yield in potatoes significantly by 15% due to improved tuber size distribution. PRD increased antioxidant content significantly by approximately 10% in both potatoes and fresh tomatoes. Under a high temperature regime, full irrigation (FI) should be undertaken, as was clear from field observations in tomatoes. For tomatoes full irrigation should be undertaken for cooling effects when the night/day average temperature >26.5 °C or when air temperature >40 °C to avoid flower-dropping. The temperature threshold for potatoes is not clear. From three-year field drip irrigation experiments we found that under the establishment phase, both potatoes and tomatoes should be fully irrigated; however, during the later phases deficit irrigation might be applied as outlined below without causing significant yield reduction:

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Potatoes

°

After the end of tuber initiation, DI or PRD is applied at 70% of FI. During the last 14 days of the growth period, DI or PRD is applied at 50% of FI.

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Fresh tomatoes

°

From the moment the 1st truce is developed, DI is applied at 85-80% of FI for two weeks. In the middle period, DI or PRD is applied at 70% of FI. During the last 14 days of the growth period, DI or PRD is applied at 50% of FI.

•

Processing tomatoes

°

From transplanting to fruit setting at 4th-5th cluster, the PRD and DI threshold for re-irrigation is when the plant-available soil water content (ASWC) equals 0.7 (soil water potential, Ψ_soil = −90 kPa). During the late fruit development/ripening stage, 10% of red fruits, the threshold for re-irrigation for DI is when ASWC = 0.5 (Ψ_soil = −185 kPa) and for PRD when ASWC (dry side) = 0.4 (Ψ_{soil, dry side} = −270 kPa).

The findings during the SAFIR project might be used as a framework for implementing water-saving deficit irrigation under different local soil and climatic conditions.     

Contextual influences on animal decision‐making: Significance for behavior‐based wildlife conservation and management

Survival and successful reproduction require animals to make critical decisions amidst a naturally dynamic environmental and social background (i.e. “context”). However, human activities have pervasively, and rapidly, extended contextual variation into evolutionarily novel territory, potentially rendering evolved animal decision‐making mechanisms and strategies maladaptive. We suggest that explicitly focusing on animal decision‐making (ADM), by integrating and applying findings from studies of sensory ecology, cognitive psychology, behavioral economics and eco‐evolutionary strategies, may enhance our understanding of, and our ability to predict how, human‐driven changes in the environment and population demography will influence animal populations. Fundamentally, the decisions animals make involve evolved mechanisms, and behaviors emerge from the combined action of sensory integration, cognitive mechanisms and strategic rules of thumb, and any of these processes may have a disproportionate influence on behavior. Although there is extensive literature exploring ADM, it generally reflects a canalized, discipline‐specific approach that lacks a unified conceptual framework. As a result, there has been limited application of ADM theory and research findings into predictive models that can enhance management outcomes, even though it is likely that the relative resilience of species to rapid environmental change is fundamentally a result of how ADM is linked to contextual variation. Here, we focus on how context influences ADM, and highlight ideas and results that may be most applicable to conservation biology.     

面向过程挖掘的C4．5在营销决策支持系统中的应用

产品营销过程中,企业需从目标市场中判断高、中、低档产品,哪类更适合其市场需求,以此可使在复杂的市场环境下及时调整产品结构,适应市场需求变化。本文采用数据挖掘C4．5算法,将原有的硒数据经处理后,导入到数据仓库中形成结构化数据,采用过程挖掘的方法对挖掘结果进行分析和评估,充分发挥决策支持系统的辅助决策作用。     

最优分割尺度支持下高分遥感影像水土资源信息分类

为提升水土资源信息分类精度,以无人机航拍获取的高分辨率影像为实验对象,提出了最优分割尺度和决策树支持下的对象级影像分类方法。首先,根据影像内部的同质性和异质性,建立了分割质量函数,通过该函数获取了最优分割尺度;然后,提出了基于光谱信息和面积信息的最优分割尺度评价模型对分割结果进行评价;最后,引入决策树规则机制,完成了水土资源信息分类,并与最大似然法分类结果进行对比。研究结果表明:所建立的分割质量函数能准确获取最优分割尺度,有效避免了人工分割带来的主观性,所提方法分类总体精度为86.78%,最大似然分类方法总体精度为77.59%,在分类精度上有较大提升。