氮素水平对不同穗型水稻品种植株衰老和产量的影响

在大田条件下,研究了两种氮素水平对直、弯穗水稻品种植株生长、叶片衰老和产量的影响。结果表明,高氮条件下两品种的朱粗度和叶片性状均优于低氮条件。增施氮肥能提高剑叶的叶绿素含量,延长叶绿素含量缓降期,使植株在生育后期能保持较高的绿叶面积;同时能提高剑叶的全氮含量,延长光合速率高值持续期,增加植株的干物质积累和籽粒产量。在同一氮素水平下,直立穗型品种的植株粗度、剑叶活力、籽粒灌浆速率、千粒重、生物产量及籽粒产量均略优于弯曲穗型品种。     

不同行向对不同穗型水稻品种群体光能分布的影响

对于不同穗型水稻品种不同行向对水稻群体光化分布进行了分析，结果表明：直立穗型群体内各高度处向光行测光照强度均高于弯曲穗型群体。直立穗型行距对行内的光照强度影响大，弯曲穗型株距对行内的光照强度影响大。弯曲穗型比直立穗型更适于东西行向种植。     

不同穗型水稻品种灌浆期生理特性的差异

在大田条件下，研究了直立穗和弯曲穗型水稻品种灌浆期部分生理特性，结果表明：直立穗型品种上3叶叶绿素含量明显高于弯曲穗型品种，且随生育进程叶片衰老较慢；直立穗型品种的剑叶和倒3叶SOD、ATPase活性比弯曲穗型品种的高，而POD活性则是弯曲穗型品种的高；直立穗型品种的强势粒中ATPase活性在灌浆前期高于弯曲穗型品种，而灌浆后期则低于弯曲穗型品种。直立穗型品种的强势粒和叶片中内源激素ABA的含量在灌浆前期都低于弯曲穗型品种，而灌浆后期则高于弯曲穗型品种。     

不同穗型水稻群体垂直入射光分布及其对光合作用的影响

依据推导的水稻上三叶截获垂直入射光的模型，并结合叶面光强与光合速率的经验公式对上三叶光合作用理论值进行了分析，结果表明：穗的直立或弯曲是决定垂直入射光在群体内分布及其对应的上三叶总光合作用的关键性状。直立穗型水稻沈农265株形好，具有较高的光合作用理论值，如果将辽粳294的叶型与沈农265的穗型相结合，有可能通过密植提高上三叶光合作用量，达到增产的目的。     

不同穗型水稻产量与群体生理性状的关系

根据穗倾角穴穗颈节至穗尖的连线与茎秆延长线的夹角雪的大小,将参试的12个品种划分为直立穗型、半弯曲穗型、弯曲穗型3种类型,研究了不同穗型的群体形态生理性状与产量形成的关系。结果表明,弯曲穗型品种抽穗期干物重较高,直立穗型品种抽穗后和成熟期干物重较高,抽穗后干物重占成熟期干物重的百分比也较高,半弯曲穗型上述方面介于二者之间。直立穗型、半弯曲穗型和弯曲穗型的颖花/叶值相近,说明三者单位叶面积所负担的颖花数差异不大。就粒重/叶而言,直立穗型>半弯曲穗型>弯曲穗型。直立穗和半弯曲穗型品种抽穗后单个颖花拥有的干物质越多,成粒率越高。比叶重大的品种,抽穗后群体叶面积衰减缓慢,具有一定的群体叶面积,对干物质生产和产量的形成是十分有利的。     

田间配置方式对不同穗型水稻生理特性的影响

田间配置方式对不同穗型水稻生理特性影响的结果表明，品种间叶绿素含量存在较大差异，辽粳326的上2叶叶绿素含量显高于奥羽316；品种、行距对可溶性糖含量的影响达到极显水平，行向之间、行向与品种互作对可溶性糖含量的影响达到显水平，辽粳326比奥羽316高，40cm行距高于30cm行距，南北行向高于东西行向。行距对群体光合速率影响较大，扩大行距对提高群体中午时的群体光合速率有利。     

直立穗型水稻品种演进状况分析

20世纪上半叶 ,国内外开始陆续出现了直立穗型水稻品种。自1974年辽宁省农作物品种审定委员会成立以来 ,共审定直立、半直立穗型水稻品种30个 ,占审定品种总数的36.6% ,其中 ,“八五”期间达到审定品种总数的32% ,“九五”期间则上升到55%。自20世纪90年代以来 ,辽宁省直立穗型水稻品种的种植面积迅速扩大 ,年种植面积从6.67×104hm2提高到26.67×104hm2 ,种植比例也迅速提高 ,从15%左右提高到50 %以上 ,1999年高达63.6%。辽宁省审定的直立穗型水稻品种中 ,有2/3的品种直立穗型基因来自意大利古老品种巴利拉 ,而且与辽粳5号亲缘关系密切。中国北方地区 (除辽宁省外 )推广种植的直立穗型水稻品种中 ,有53.3 %的品种与巴利拉有亲缘关系。以辽宁省审定的62个粘型常规水稻品种为对象进行对比分析 ,发现直立穗型品种相对于弯曲穗型品种 ,具有产量潜力较高 ,株高较矮、穗型短小而着粒密度较大等特点     

水稻直立穗型基因多效性的研究

以直立穗型品种辽粳5号和弯曲穗型品种丰锦杂交后代来自同一F4单株的F5世代不同穗型植株为试材，对其茎叶性状和穗部性状进行测定，分析直立穗性状与其他性状的关系。结果表明：(1)直立穗型植株较矮，叶片短而宽，叶鞘长且上部节间短，而弯曲穗型则相反；(2)不同穗型植株2次枝梗、2次枝梗籽粒、2次枝梗空秕率在穗轴上的分布趋势很相近，但是直立穗型2次枝梗空秕率极显高于弯曲穗型，而1次枝梗空秕率在不同穗型间差异不明显，选育1次枝梗籽粒比率高，2次枝梗籽粒主要分布在上部的直立穗型品种，有利于改善结实性；(3)直立穗性状有可能是不完全显性。     

水稻冠层光谱特征及其与LAI的关系研究

氮素营养是影响作物生长与产量的最主要限制因子之一。准确及时地监测或诊断出作物氮素营养状况,对提高氮素利用效率和作物管理水平、减少过度施氮造成的环境污染具有重要意义。本研究在不同施氮水平处理的水稻试验小区,对水稻整个生长期内冠层反射光谱进行了较系统、密集的测定,同时测定了几个重要生育期水稻的叶面积指数。研究结果表明:随着施氮量的增加,水稻冠层光谱在各生育期间呈现出一定的规律性,在近红外部分(710～1 220 nm),冠层光谱反射率随着施氮水平的提高而升高,而在可见光部分(460～680 nm),水稻冠层的光谱反射率反而逐渐降低。经冠层光谱差异显著性检验发现:水稻灌浆期以前,对施氮水平最为敏感的波段是绿光(560～610 nm)和近红外(710～760 nm)部分;转换为归一化植被指数(NDVI)以后,差异最显著的是(R760-R560)/(R760+R560)。不同氮肥处理的水稻LAI随时间变化曲线大致都呈抛物线型,中低水平施氮肥水稻LAI随时间的变化曲线比较平缓,而高水平施氮肥LAI曲线则变化比较剧烈。冠层光谱反射与叶面积的相关分析结果表明:在水稻抽穗前,叶面积与冠层光谱反射率相关性较差;而抽穗后,叶面积与冠层光谱有较高的相关性。     

沈阳农业大学学报2001年总目录(第32卷)

第一期研究报告沈阳农业大学“十五”科技发展构想……………………………………………………………………………张树林 ,孙占慧（３）作物育种与栽培不同氮素水平对直立穗型水稻品种群体光合特性的影响…………………………………………刘宛 ,徐正进 ,陈温福 ,等（８）直立穗型水稻品种主要性状与选育技术的讨论……………………………………………………谈伟 ,陈振武 ,谈松（１３）玉米新品种优化栽培措施研究………………………………………………………………………陈志斌 ,唐劲驰 ,郝宪彬 ,等（１７）农业气象东北地区低温冷害年的环流…     

蓝牙RFCOMM协议层的研究与实现

分析RFCOMM协议及其连接模型和通信流程,提出一种基于有限状态机模型的RFCOMM-L2CAP异步通信结构。针对RFCOMM底层唯一存在的L2CAP信道的复用模型,通过异步化事件处理统一维护RFCOMM连接与L2CAP信道的引用关系,优化蓝牙协议栈层间的通信效率和实时性。     

归纳学习算法CAP2的研究与应用

本文提出以实例空间中状态划分概率的大小作为启发式信息，以提供的正反实例集为依据，基于二叉树分类方法的示例式归纳学习算法ＣＡＰ２．它输出的分类规则是谓词演算表达式．该算法可根据用户对精度的要求控制分类深度，得到不同精度的规则，并能处理连续数据、噪音数据和利用用户提供的背景知识，既适用于同时给定概念的正、反例集的情况，也适用于只给正例集的情况．本文还介绍了ＣＡＰ２算法的应用情况，并和著名的ＩＤ３算法进行了比较．ＣＡＰ２已嵌入到一个自动知识获取系统．     

一种在连续MFR中快速挖掘频繁访问路径的新算法

频繁访问路径挖掘是Web数据挖掘的重要研究内容。论文主要研究在最大前向引用中发现连续频繁访问路径的问题,提出了一种快速有效的CAP算法,该算法借助于访问路径树进行挖掘,只需一次扫描数据库,且简化了对访问路径树的挖掘过程,试验表明在执行效率上明显优于WAP算法。     

采用面向对象技术设计实现逻辑链路控制和适配协议

逻辑链路控制和适配协议是蓝牙协议栈中数据链路层的一部分。利用面向对象的分析和设计思想,应用标准建模语言的建模技术,对L2CAP协议进行了设计和实现。     

Automated detection of cyclic alternating pattern and classification of sleep stages using deep neural network

The visual sleep stages scoring by human experts is the current gold standard for sleep analysis. However, this method is tedious, time-consuming, prone to human errors, and unable to detect microstructure of sleep such as cyclic alternating pattern (CAP) which is an important diagnostic factor for the detection of sleep disorders such as insomnia and obstructive sleep apnea (OSA). The CAP is only observed as subtle changes in the electroencephalogram (EEG) signals during non-rapid eye movement (NREM) sleep, making it very difficult for human experts to discern. Hence, it is important to have an automated system developed using artificial intelligence for accurate and robust detection of CAP and sleep stages classification. In this study, a deep learning model based on 1-dimensional convolutional neural network (1D-CNN) is proposed for CAP detection and homogenous 3-class sleep stages classification, namely wakefulness (W), rapid eye movement (REM) and NREM sleep. The proposed model is developed using standardized EEG recordings. Our developed CNN network achieved good model performance for 3-class sleep stages classification with a classification accuracy of 90.46%. Our proposed model also yielded a classification accuracy of 73.64% using balanced CAP dataset, and sensitivity of 92.06% with unbalanced CAP dataset. Our proposed model correctly identified majority of A-phases which comprised of only 12.6% in the unbalanced dataset. The performance of the developed prototype is ready to be tested with more data before clinical application.

     

Eliciting knowledge for software development

A current bottleneck in the automation of cognitive tasks, such as software development, is the lack of available, standardized, reliable and valid methods for extracting knowledge from experts. This paper discusses the development of Computer Aided Protocol (CAP) to automatically collect the general and specific cognitive task components of subjects performing a programming task. The effectiveness of CAP is evaluated in a statistically balanced experimental design (n = 30) by comparing it to traditional protocol analysis and a control group. Results indicate that while neither treatment significantly altered the solution process, CAP was able to collect the lower level commands while protocol analysis collected only 56% of these lower level commands. However, protocol analysis was able to obtain significantly more high level goals than CAP. This work suggests that the integration of both protocol and CAP for knowledge extraction would provide more effective information for the development of expert systems than is feasible with either system alone.     

蜂窝网中基于分布式约束满足算法的改进信道分配

随着蜂窝网业务需求的不断增长,如何利用有限的信道资源在各小区间进行复用,以便既能避免移动用户之间的干扰,又能满足所有移动用户的话务请求,使蜂窝系统容量大大增加,已成为一项重要研究课题。此类问题属于NP-hard的信道分配问题(Channel Assignment Problem,CAP),将CAP问题形式化为分布式约束满足问题(DC-SP),然后提出基于改进现有的信道分配策略,以获得更高的信道利用率、较令人满意的系统服务质量,尽可能满足所有用户的话务请求。将利用尽可能简单、搜寻时间短的算法,并将现有的benchmark问题进行仿真。实验表明,该方案对有效改进信道分配问题,充分利用有限的信道资源,降低系统的阻塞率,有着较好的应用前景。     

Eliciting knowledge for software development

Abstract

A current bottleneck in the automation of cognitive tasks, such as software development, is the lack of available, standardized, reliable and valid methods for extracting knowledge from experts. This paper discusses the development of Computer Aided Protocol (CAP) to automatically collect the general and specific cognitive task components of subjects performing a programming task. The effectiveness of CAP is evaluated in a statistically balanced experimental design (n = 30) by comparing it to traditional protocol analysis and a control group. Results indicate that while neither treatment significantly altered the solution process, CAP was able to collect the lower level commands while protocol analysis collected only 56% of these lower level commands. However, protocol analysis was able to obtain significantly more high level goals than CAP. This work suggests that the integration of both protocol and CAP for knowledge extraction would provide more effective information for the development of expert systems than is feasible with either system alone.     

Use of instructional technology to improve teacher candidate knowledge of vocabulary instruction

Teacher educators play an influential role in the chain of improvement needed to address gaps in vocabulary knowledge and performance for some children. If created in careful accordance to design principles, multimedia can serve as a tool to improve preservice teacher knowledge in this domain. The present experimental study investigated a multimedia-based intervention, which pairs a modeling video with a Content Acquisition Podcast (i.e., video plus CAP), to teach preservice teachers (n = 101) about an effective vocabulary intervention for students at risk for or with learning disabilities. Preservice teachers were randomly assigned to either watch a video plus CAP or read a practitioner-friendly reading on vocabulary instruction. Those who watched the video plus CAP significantly outperformed the comparison group on a posttest and maintenance test of knowledge.     

基于DSP的V/F式数据采集系统设计

首先介绍了DSP中集成捕获单元(CAP)的特点,灵活应用CAP的功能,将它和压频转换器(VFC)相结合,构成了一个新的数据采集系统,并分析了其模/数转换误差。该系统不仅具有以往的V/F式数据采集易于信号隔离、抗干扰性强的特点,而且硬件构成简单,很大程度地节约了成本,简化了硬件电路设计。