验证马吕斯定律常采用半导体激光器为光源,使激光先后通过两块偏振片,改变两块偏振片偏振化方向夹角,测量激光光强随夹角的变化关系,从而验证马吕斯定律.通常会误认为,实验中旋转任意一块偏振片都可以改变偏振片夹角,得到实验验证结果.但通过实验及理论分析发现,由于半导体激光器在各方向上振幅不等的偏振特征,只有转动第二块偏振片才能得到理想的实验验证结果.

In this study, we propose a method for correcting the adverse effects produced by the cur vature of fruit objects in images acquired by cameras in machine vision systems. The areas near the edge are darker in acquired images than in the centre, which results in many difficulties for subsequent analyses. In this paper, the fruit object was considered as a Lambertian surface. The light intensity was analysed and the height and normal on fruit surface was deduced based on the shape-from-shading (SFS) algorithm. The geometric correction factors were calculated and the adverse effects of light intensity were corrected on the fruit surface. The proposed method was evaluated on a test set of four types of fruit. The results show that the non-uniformity of the greyscale value on the fruit surface fell by 35.5% after correction, and the ref lectance in the central area of fruit is similar to that of the peripheral areas when using the proposed method. The experiments prove that our method allowed homogenisation of the greyscale level of the pixels belonging to the same class, regardless of where they are on the fruit surface, which will facilitate subsequent classification tasks.

This research introduces an important noninvasive technique which is In vivo measurement of human body bone lead. It makes use of the miniature X tube emitting X-ray through sebum to stimulate the characteristic X fluorescence at the position of tibia under its surface about 1 similar to 1.5 mms. The characteristic X fluorescence which express bone lead content and asking for help from Si-PIN detector and M.C.A analysis system to output a bone lead density d. This technique use the relative functions between sebum thick t and spectrum-unfolding area Omega for bone lead peak. The Compton scatter integral value C could represent sebum thick. It will be calculated the lead content of tibia with ppm. The experiment of this instrument measured 52 data gained by volunteers. This measurement results with other measuring results by international researches are mutually fits together. Thus it is credible that the N-XRF instrument can be possible in vivo to measure bone lead in human body.

The objective of this study was to determine the effects of soybean oil, moisture and setting on the texture and color of surimi gels. Increasing the moisture and soybean oil contents resulted in increased whiteness values in the gels, but reduced the breaking forces, hardness and chewiness. The highest deformation, cohesiveness and resilience values were observed in gels with 78% moisture, while the lowest in gels with 80% moisture. At soybean oil content >3%, gels with 80% moisture had a lower springiness than those with 76% and 78% moisture. Setting significantly increased the breaking force, deformation, hardness, cohesiveness, chewiness, resilience and whiteness of surimi gels with soybean oil. Results indicated that soybean oil and setting procedure could be used to modify the texture and color of surimi-based products.Practical ApplicationsIn China, animal fats are often added into surimi-based products to improve their flavor, taste and color. In the present study, soybean oil was added into the surimi, while the effects of soybean oil associated with the surimi moisture and setting on the textural and color properties of surimi gel were investigated. The study was aimed to provide experimental evidence for application of vegetable oils in the production of surimi-based products.

In this paper, we present a real-time measurement and adjustment method, based on scanning imaging, for optical transmitter which emits 90°×2° linear laser beam. This novel optical arrangement consists of an area array CCD and two linear array CCDs. According to the relationship between the positions, angles of transmitter optical components and the beam parameters of emergent laser, the system can help us to decide the real-time adjustment of optical transmitter by measuring the related beam parameters. In order to improve the measurement speed, avoid occlusion and ensure simultaneous measurement, the two linear array CCDs are placed at near field, far field and separated by a definite angle to acquire the beam intensity distribution through suitable nonlinear correction during the process of scanning. After a complete scanning, the beam parameters and the spot image are acquired by continuous measurement. The proof-of-principle experiments showed that the measurement results were in agreement with the analysis. The presented method was applied to direct fast adjustment for higher quality on the assembly of the optical transmitter. The presented procedure is highly advantageous for diverse laser beam emitted from the optical transmitter, such as elliptic, linear and so on.

We propose a scanning imaging measurement method using two linear array charge coupled devices (CCD) to evaluate the transmission performance of the linear laser beam of 90° × 2°. The two linear array CCDs are placed at two positions in the far field separated by a definite angle. The beam divergence angles in the view direction are measured by linear fitting because the beam width conforms to the linear relationship in the far field. This method has the ability for real-time testing and is appropriate for the complicated beam shapes with a wide measurement range.

This paper discusses a new in vivo XRF bone lead detection system and introduces how to study the radioactive activity, exposure rate, absorb doses, equivalent dose and effective dose of the system using the long life source of 238Pu and analyzes the dose safety about the system.

A review of previous studies on automatic locating fruits on trees using computer vision methods was performed.The main features of these approaches were described,especially focusing on the sensors utilized for capturing tree images,the image processing strategy used to detect fruits,the results obtained in terms of the correct/false detection rates,and the advantages and limitation of the systems.The majority of these works use CCD cameras to capture the images and use local or shape-based analysis to detect the fruits,use multi cameras or range senses to locate the fruits.The affecting factors of these systems such as the intensity of light,occlusion,and algorithm efficiency were pointed out;and some opinions and advices on machine vision system were given.

生物样品折射率的空间变化导致了光学畸变的产生,这种畸变对于共聚焦显微镜观察厚的生物样品和活体体内组织成像是一种严重的限制.自适应光学(AO)技术是通过快速反应的变形镜使镜面发生形变来补偿像差,在共聚焦显微镜中应用自适应光学技术可以校正光学畸变,观察深层组织活动,进行活体成像和实时检测.详细分析了共聚焦显微镜中像差的来源及光学畸变的特点,讨论了目前在共聚焦显微镜中自适应光学校正的方案及研究现状,讨论了共聚焦显微镜中自适应光学的波前传感器、畸变测量和波前校正器,并探讨了目前超高分辨率显微成像技术的发展方向.

Using Huafengyouza No.8 as the experiment subjects,this study focused on the impact of He-Ne laser radiation luminance and time on the growing length of stems and leaves of brassica napus seeds.Compared with the control group,the research results showed that the length of stems and roots has the largest growing extent when the radiation luminance at 20.78 Fc and the radiation time at 15 minutes.The stem increased by 2.1 cm and the root increased by 0.18 cm.

为研究柑橘在输运过程中着地后的硬度变化,设计了柑橘从不同高度落下,采用FHM-1型水果硬度计检测柑橘着地后的硬度以及放置时间所对应的硬度;得到了柑橘从不同高度下落后的硬度关系曲线和柑橘放置的天数与硬度的关系图,为后续检测柑橘品质奠定基础。

With the full use of computer vision and neural networks,this paper presents an automatic classification method in the stored-grain pests.Through the pretreatment to the CCD image of stored-grain pests,we extracted nine shape features,by the feature selection,we get six features as the input parameters of neural networks.By use of Self-organizing Feature Map Neural Network model,an experiment for recognizing twenty samples of four kinds of stored-grain pests was performed,and the accurate recognition ratio reached 91.3%.

An optimized method of holography is presented,in which only a piece of ground glass is used in the experiment.It is shown that the optical path is simple and the effect is very good.

探讨了如何根据物理学科特点,加强大学物理教学,培养学生创新思维能力,科学精神以及良好的学习习惯和优秀的思想品德。

Combining with the characteristic of agriculture universities, this paper made a useful experiment importing the electronic technigue in the temperature effect of fruits' electromotive force.

介绍了光电传感器在播种、喷雾和移栽等方面的应用情况,指出了光电传感器在我国农业机械中具有广阔的应用前景。

Food safety has been an important problem that people concern much. As a convenient, quick, efficient measuring technique, supersonic wave has been applied widely in measuring food safety. This paper introduces the principle of supersonic wave, describes the latest development of supersonic wave in measuring food safety and points out its unique advantage and bright future in measuring fruit and vegetable products, meat products, milk products and other aspects.

回顾了全息术的历史,阐述了全息术的基本原理,然后介绍了全息术在实际中的应用及其发展方向。

根据家禽种蛋经光照后能提高孵化率的特点,设计了家禽孵化环境光照度模糊控制器,并阐述了模糊控制系统的原理、方法以及硬件的组成.通过仿真试验,结果表明,该系统响应快,超调量小,动作准确,过程平稳.