玉米小斑病病害程度图像检测

为了实时获取作物病害程度信息,研究了一种基于RGB彩色模型的玉米小斑病图像的分割方法,并利用分割结果求得的玉米冠层危害程度来计算整株玉米的发病程度.由于图像中背景复杂,将叶片与病斑同时分离出来的可能性小,故该方法分为两步:首先从获取的RGB图像中提取R、G、B分量,利用2G-R-B图像采用迭代法自动选取阈值将玉米叶片从背景中分割出来;然后根据R-G图像将病斑从叶片上分离出来.30幅图像中玉米叶片、病斑基本上能提取出来,但没有黄化的少量侵染点无法有效分割.     

杂草对AHAS抑制剂的抗药性分子机理研究进展

除草剂在田间的重复及不合理使用,导致了杂草抗药性的发生和发展。其中AHAS抑制剂由于靶标单一,抗性发展十分迅速。截至2009年,已有103种杂草对AHAS抑制剂产生了抗药性,占19类化学除草剂总抗药性杂草生物型的近1/3。从AHAS基因突变位点及种类与杂草抗药性水平的关系、AHAS基因突变与AHAS酶活性的关系、AHAS基因拷贝数与杂草抗药性的关系以及AHAS酶与除草剂结合前后的三维结构等方面,综述了杂草对AHAS抑制剂产生抗药性的机理,旨在为AHAS抑制剂抗性研究提供参考。并对自然种群目标基因的等位基因检测技术(ECOTILLING)和衍生型酶切扩增多态性序列(dCAPS)两种通过检测等位基因多态性的手段快速诊断抗药性杂草的新技术进行了介绍,讨论了延缓杂草抗药性发生和发展的策略。     

2009—201O年新疆地区家禽禽流感免疫抗体监测与分析

2009--2010年,对新疆部分地区蛋鸡、肉鸡、家养水禽的养殖场随机采集血清样品10193份,活禽市场采集血清样品1620份。用HI方法对禽流感免疫抗体进行检测,结果表明：蛋鸡的H5免疫抗体合格率为33．33％～100％,其中0效价率为33．33%-80．00％;H9免疫抗体合格率为62．4%-100％,20%-33％蛋鸡场存在100％的0效价现象。肉鸡H5免疫抗体合格率为0％-100％,其中7．69%-69．6％肉鸡群中H5抗体0效价率为100％。水禽的H5免疫抗体合格率为0%-100％,有25％33．33％鸭群全部是0效价。活禽市场H5抗体效价≥410g2的比例为10．59％-83．57％,H9抗体效价至410醇的比例21．70％-67．14％。     

骆驼乳研究进展

本文介绍了骆驼乳的营养和生物学价值,影响骆驼乳品质的因素,以及骆驼乳掺假鉴定技术,展望了骆驼乳的开发前景,以期为骆驼乳的研究提供理论依据.     

驾驶员疲劳检测技术的研究现状及发展趋势

介绍了国内外对于驾驶员疲劳状态检测技术的研究现状,并对几种具有代表性的产品进行了评述;PERCLOS是一种目前最有效的、车载、实时的驾驶疲劳测评方法;提出了驾驶疲劳状态检测研究应着重于驾驶疲劳形成机理和模型建立、疲劳状况检测及其评价方法、驾驶员疲劳报警装置的研究及应用,并实现驾驶员疲劳状态检测及预警装置商品化的研究思路。     

Research Progress in Detection of Milk by Immunological Technique

With the rapid development of science and technology and people's living standard rasing,the awareness of food safety is becoming more and more high,and people pay a lot of attention to the quality and safety of milk.This paper summarized research progress in detection of milk by immunological technique,including enzyme linked immunosorbent assay (ELISA),immunofluorescence technique (IFT),immune colloidal gold technique (ICGT),immune polymerase chain reaction,immune chip technology in application of the milk quality detecting and their advantages and disadvantages,aiming to provide references at further developing the application of immunological techniques in quality detecting of milk.     

Theoretical and experimental deflections of glued laminated timber beams made from a tropical hardwood

Abstract

Nondestructive testing (NDT) can play an important role in improving the quality and reliability of tropical hardwood as an engineering material. By means of these methods, the stiffness of the material can be determined and the information used to improve its structural performance. Although, it is a usual approach for qualifying the material used to manufacture engineered wood products made mainly from softwoods, it is not so common for tropical hardwoods. Additionally, the lack of information regarding properties of glulam beam made from these kinds of wood is evident. In this context, the paper aimed at evaluating the theoretical and experimental deflection of glulam beams made from the Brazilian hardwood louro-vermelho (Sextonia rubra). Initially, the stiffness of each lamina was determined nondestructively using transverse vibration method (E _dtv), which has been demonstrated to be the most suitable method for this wood species. Then, ten 5-lamina glulam beams were assembled according to descending lamina E _dtv values. The experimental evaluation was performed using a four-point bending schedule. In general, the theoretical values of deflection were 2% higher than the experimental ones. The transverse vibration showed to be a suitable method to both measure lamina stiffness and predict glulam beam deflection.     

Applications of wavelet transformation in the nondestructive test of medium density fiberboard

Taking medium density fiberboards (MDF) as samples, the feasibility of the applications of wavelet analysis in a nondestructive test is discussed in this paper. The main results are as follows: the modulus of elasticity of longitudinal resonance, measured by wavelet analysis, can replace the conventional static modulus of elasticity. Their correlation coefficient is significant (p < 0.01). The defect of samples can be judged by wavelet analysis, which is superior because it is a nondestructive test. __________ Translated from Scientia Silvae Sinicae, 2006, 42(10): 91–94 [译自: 林业科学]     

近红外光谱定量和定性分析技术在鲜食葡萄果实无损检测中的应用

选取10种不同鲜食葡萄品种、3个不同成熟期和1种病害的果实共计188个葡萄果实样品,并采集果实样品的近红外光谱。建立了以葡萄果实的总酚、总糖、果糖、蔗糖和可溶性固形物为指标的偏最小二乘(PLS)定量分析模型,模型的可信度较高,除少数指标的相关系数在0.77~0.89,其余指标均在0.90以上,均方根误差在0.022~1.410。结合主成分分析法,对谱区为4 119.20~9 881.46 cm^-1的光谱建立了区分葡萄果实品种、成熟度和是否受病害的判别分析(DA)模型,模型的正识率依次为92.11%、88.89%和96.15%。研究表明,近红外检测技术可用于鲜食葡萄果实的5个主要内含物的定量分析以及果实品种、果实成熟度和有病虫害的二次果进行的定性识别。     

基于虚拟仪器的农村小钢铁厂电压谐波检测

利用虚拟仪器LabVIEW软件设计了谐波检测平台，对农村某加工钢铁制品企业变电所的电压谐波状况进行模拟，并采用快速傅里叶方法通过加窗函数进行谐波分析，分析结果由LabVIEW的RGT工具包进行编程并生成报表，通过报表可以清晰地了解到该企业电能质量状况。