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排序方式: 共有363条查询结果,搜索用时 15 毫秒
141.
Solveig Danielsen Eric Boa Moses Mafabi Emmanuel Mutebi Robert Reeder Flavia Kabeere 《The Journal of Agricultural Education and Extension》2013,19(2):183-201
Abstract Purpose: This study developed a framework for quality assessment of diagnoses and advice given at plant clinics. Design/methodology/approach: Clinic registers from five plant clinics in Uganda (2006–2010) were used to develop quality assessment protocols for diagnoses and advice given by plant doctors. Assessment of quality of diagnoses was based on five validation criteria applied on the ten most common crops. Quality of advice was assessed for the four major problems considering efficacy and feasibility. Findings: The quality of diagnoses varied between crops, from 68% completely validated in maize to 1% in tomato. Complete and partially validated diagnoses were 44% of all queries. The remaining 56% were rejected. Several basic weaknesses were found in data recording and symptom recognition. A greater consistency and precision in naming diseases would increase the number of completely validated diagnoses. The majority of recommendations (82%) were assessed ‘partially effective’. ‘Best practice’ was recommended for 10% and ineffective advice was given in 8% of the cases with considerable variation between diseases. Practical implications: Plant doctors need more training in symptom recognition, pest management and record keeping as well as better technical backstopping to solve unknown problems. Common standards and procedures for clinic data collection and analysis should be established, and roles and responsibilities clearly defined. Originality/value: This is the first time plant clinic registers have been used to systematically assess quality of plant clinic services. Apart from being a valuable tool for quality assessment of extension, the plant clinic registers constitute a novel source of regular information about pests, diseases and farmer demand that can help improve decision-making of extension service providers, researchers, plant health authorities as well as information and technology providers. 相似文献
142.
刘秋成 《衡阳师范学院学报》2013,(5):117-119
外加状语在语篇构建中起着重要作用,在外加状语的人际意义连贯框架中,外加状语可以通过发挥语篇内人际意义衔接功能和语篇外协调语域的一致性而最终实现其语篇人际连贯功能. 相似文献
143.
项伟 《长江工程职业技术学院学报》2013,(4):37-38
详细介绍了S3C2440 ARM处理器GPIO接口编程和LED硬件电路,阐述了基于S3C2440开发板利用GPIO接口实现LED灯点亮功能的原理与程序设计方法功能实现. 相似文献
144.
甘小林 《佳木斯教育学院学报》2012,(2):293-293
"网络语言"是一种特殊的言语现象,作为一种社会现象、文化现象,语言学尤其是社会语言学,应当重视它、研究它。网络语言是网民们群体内部使用的形式,从本质上看是一种特殊的语言变体,它和我们日常生活中所用的语言有着较大的差别。本文从社会语言学的角度分析了网络语言这样一种社会现象及其特点,并强调要正确看待网络语言的变异及其发展。 相似文献
145.
研究了文献[1]中的模映射,证明其拓扑熵为0,另外利用该映射证明了拟移位映射和移位映射拓扑共轭,从而揭示出拟移位映射是移位映射的一个重要的拓扑共轭系统. 相似文献
146.
147.
We propose a novel texture clustering method. A classical type of (approximate) shift invariant discrete wavelet transform (DWT), dual tree DWT, is used to decompose texture images. Multiple signatures are generated from the obtained high-frequency bands. A locality preserving approach is applied subsequently to project data from high-dimensional space to low-dimensional space. Shift invariant DWT can represent image texture information efficiently in combination with a histogram signature, and the local geometrical structure of the dataset is preserved well during clustering. Experimental results show that the proposed method remarkably outperforms traditional ones. 相似文献
148.
提出一种逐次逼近型模数转换器(successive approximation register analog-to-digital converter,SAR ADC)高能效电荷均值开关方法。该方法能够提供恒定的共模电压VCM,大小为VREF的一半,且只需要使用两个参考电压VREF和地,避免了额外的电压基准电路。为了增加一位精度并保持恒定的共模电压,C-2C结构替代参考电容C。与单调开关方法相比,该方法能耗减少66.65%,电容面积减少49.41%。行为仿真结果证明了该方法的有效性。 相似文献
149.
The的语域及应用 总被引:1,自引:0,他引:1
吴俊 《兰州石化职业技术学院学报》2005,5(3):35-37
由于冠词的用法较为复杂,又因汉语中没有冠词,学习英语的人能够真正地掌握冠词尤其是定冠词的基本用法较为困难,也容易忽视.在书面语语域中,定冠词比不定冠词出现的多,这是因为定冠词的使用范围要广.讨论了the的语域及其应用. 相似文献
150.
廖福涛 《江西师范大学学报(哲学社会科学版)》2007,40(6):130-133
大学英语的教学不能仅满足于词汇语法的教学,还应融入语类意识。所谓语类,指的是具有某种固定语言结构特征的语篇类型,它能有效地呈现语言功能与语言形式之间的关系。通过对大学英语教材中出现的语类进行不同层面的分析,发现语言表达方式与语域密切相关,语域因素的变化会导致语类的多样性及其变体的产生,因此,熟悉并掌握不同风格的语类框架对提高学生欣赏语篇、阅读及表达等各方面的能力具有极大的指导作用。 相似文献