基于机器视觉的太阳电池片计数研究

针对太阳电池片生产过程中电池片计数的效率低、误差大等问题,提出基于机器视觉的太阳电池片的自动计数系统。该系统基于机器视觉理论和数字图像处理技术,采用LED平行光源,对实时采集的微米级厚度的电池片的图像进行数据的提取、截取、滤波等一系列预处理,实现太阳电池片的关键区域的选择,降低噪声对计数的影响,并取得理想的实验结果。

X光胶片贮存式计数仪及电路

随着自动冲片机的问世和广泛应用,大大提高了暗室的工作效率。因此,把传统的人工统计方式变为自动的方式已成为必要,本电路的设计就能较好地解决这一问题。 X光片贮存式计数仪,能显示出每天各种规格X光胶片的片数;能显示每天累加的总片数;还能显示月累加数;除了这些计数、累加显示功能外,还具有贮存功能,它能将计得的数据贮存起来,再进行另一次计数。如果要读取锁存的数据,只要按下按键就可显示贮存数据了。这样对于承包后的放射科工作量的统计是非常方便和有意义的。

雪茄烟叶中霉菌快速计数测试片的筛选及主要霉菌种类的鉴定

为明确引起雪茄烟叶霉变的主要霉菌种类,并筛选出适用于霉菌快速计数的测试片,分析了市售陆桥ET005、默克MC-Media、环凯HP003、3M 70200775800、美正LR10035种霉菌快速测试片在霉变雪茄烟叶中的计数效果,并采用平板计数法比对分析5种测试片检测结果的可信度及测试周期。同时对主要霉菌进行分离和纯化,并采用形态学、ITS测序和MALDI-TOF MS相结合的方法进行菌种鉴定。结果表明:霉菌快速计数测试片法检测结果略低于平板计数法,但其操作简单,判读清晰。其中,美正霉菌快速测试片综合检测效果最好,可满足日常检测的需要。引起雪茄烟叶霉变的霉菌具有多样性,曲霉属(Aspergillus sp.)是引起雪茄烟叶霉变的主要菌属,土曲霉(Aspergillus terreus)和黄曲霉(Aspergillus flavus)均可引起雪茄烟叶霉变。

目视管理在镍钛根管锉次数管理中的应用

目的 探讨目视管理在镍钛根管锉次数管理中的应用效果。方法 选取2018年3月-5月在本科实施的160例根管预备术作为研究对象,将其分为对照组和观察组,每组各80例。对照组采用传统的管理方法对镍钛根管锉次数进行管理,观察组在镍钛根管锉次数管理中使用计数片进行目视管理,比较两组镍钛根管锉计数所需时间及发生计数错误的次数。结果 对照组镍钛根管锉计数所需的平均时间为(23. 03±2. 14) s/次,实施后为(13. 70±1. 35) s/次;对照组计数错误次数为(0. 11±0. 32)次,观察组为(0. 01±0. 11)次,且2者差异有统计学意义(P <0. 05)。结论 将目视管理应用于镍钛根管锉的次数管理,能够缩短护士计数时间,减少计数错误,从而提高工作效率,值得在临床中推广应用。

Suitable layout of gate roads related to slice mining in an ultra-thick unstable coal seam

We determi：ned a suitable gate road layout in slice mining in an ultra-thick unstable coal seam, using theoretical anallysis and numerical calculations. Based on plasticity theory in terms of limiting equilibrium, the width of chain pillar in the upper slice was calculated to be 18 m. The stress distribution in the chain pillar after the upper slice was mined out was described with numerical simulation. The extent of the effect of stress on the upper chain pillar on the lower solid coal was obtained on the basis of an elastic solution of a distributed force loaded on a half-plane. Three layout designs for lower gate roads were pro- posed and a stability factor was introduced to analyze the stability of the lower pillar with numerical calculation. Gate road translation was determined as the most suitable layout method, which maximizes the extraction rate on the basis of the pillar stability.

Erythrocyte Fragment Count Predicts Hemolysis in Roller Pumps

Objective： Hemolysis in blood pumps has been measured by various in vitro test methods, in which normalized index of hemolysis （NIH） was established. As NIH is complicated and difficult to calculate, erythrocyte fragment count is proposed in the present study to predict hemolysis in roller pumps. Methods： Five paired in vitro tests were conducted using the POLYSTAN pediatric pump（group A） and COBE pump（ group B）. Ten whole blood samples （400 ml ） were circled in the roller pump for 16 h. Erythrocyte fragments count and plasma-free hemoglobin （FHb） were measured before pumping and every two hours through circulation after four-hour-pumping. The morphological changes of erythrocyte were observed by scanning electron microscope. Results： The two groups＇ EFC and FHb levels were increased linearly during a long duration of pumping and linear regression of erythrocyte fragments count and plasma-free hemoglobin were correlated. Conclusion： Erythrocyte fragments count could be used as an index in evaluating the in vitro hemolytic properties of blood pumps.

Design of digital control DC voltage source based on AT89C52 MCU

the system to DC voltage source as the core, AT89C52 MCU as the main controller, the output voltage to set the DC power supply through the keyboard, with a step function voltage to reality, the actual output value. This design is divided into four modules： SCM control and display module, digital to analog （D/A） conversion module, a constant voltage source module, output module. MCU control module as the core, the input signal is converted to digital quantity output; constant current source module voltage D/A conversion to analog conversion into constant pressure through a constant voltage circuit. The system has good reliability, high precision.

The Practical Design Aspects of Anti-aliasing Filters for the Multirate Analog-to-digital Processing in Microcontroller Embedded System

Due to the widespread computer technology, it is difficult to imagine a research or a control of any physical object without using a powerful hardware and software applications. To use digital technologies we need to collect data of a real world in digital system by the analog-to-digital converters. Taking into account the relative high computational capabilities of modern microcontrollers the article proposes a multirate processing system. The paper presents practical design aspects of the analog and digital anti-aliasing filter fbr the measurement path. having regarded the real possibilities and limitations of today＇s filters and analog-to-digital embedded converters.

变压器噪声暴露对SD大鼠听力及应激状态的影响研究

目的:探究短时间内低声级强度低频的变压器噪声暴露对SD大鼠听力及应激状态方面的影响。方法:选取90只SPF级健康无听力障碍的(雌雄各半)SD大鼠作为实验对象,随机分为实验A、B组和对照C组,A、B组分别给予声级上限为65 dB SPL、60 dB SPL(频谱范围:100~800 Hz)的变压器噪声,噪声暴露时程为8周,每日噪声给予时间为22点至次日8点,C组在相同条件下饲养,不给予噪声暴露。噪声暴露结束后,通过DPOAE(畸变耳声发射)、ABR(听性脑干反应)检测、耳蜗铺片及毛细胞计数对SD大鼠听力学状况进行评估;通过血清中促肾上腺皮质激素(ACTH)、血清皮质醇(CORT)对SD大鼠的应激状态进行评估。结果:在变压器噪声暴露的8周内,各组大鼠生长状况良好,体重均呈正常生理性增长,组间无明显差异(P>0.05);在变压器噪声暴露8周后,对A、B、C三组大鼠的听力学指标进行两两比较,组间均无明显差异(P>0.05),对大鼠血清中促肾上腺皮质激素(ACTH)、血清皮质醇(CORT)的含量进行三组间比较,组间差异均无统计学意义(P>0.05)。结论:连续暴露于声压级上限65/60 dB SPL,频谱范围为100~800 Hz的变压器噪声下8周(10小时/天)对SD大鼠听力未产生明显影响,未引发SD大鼠应激状态。

A Straight-bladed Vertical Axis Wind Turbine with a Directed Guide Vane Row-Effect of Guide Vane Geometry on the Performance-

The objective of this study is to show the effect of guide vane geometry on the performance. In order to overcome the disadvantages of vertical axis wind turbine, a straight-bladed vertical axis wind turbine （S-VAWT） with a directed guide vane row has been proposed and tested by the authors. According to previous studies, it was clarified that the performance of the turbine can be improved by means of the directed guide vane row. However, the guide vane geometry of S-VAWT has not been optimized so far. In order to clarify the effect of guide vanegeometry, the effects of setting angle and gap between rotor blade and guide vane on power coefticlent and start- ing characteristic were investigated in the experiments. The experimental study of the proposed wind turbine was carried out by a wind tunnel. The wind tunnel with a diameter of 1.8m is open jet type. The wind velocity is 8 m/s in the experiments. The rotor has three straight blades with a profile of NACA0018 and a chord length of 100 mm, a diameter of 0.6 m and a blade height of 0.7 m. The guide vane row consists of 3 arc plates.

Investigation of performances and flow characteristics of two bi-directional pumps with different airfoil blades

Today, the most commonly used bi-directional airfoil in hydraulic machinery is the S-shaped airfoil(SA). A new bi-directional airfoil, obtained by lowering the bent airfoil camber and thickening the bone line bi-directionally, is proposed. Two bi-directional axial flow pumps, with the SA blades and the arc airfoil(AA) blades, respectively, were designed to verify the applicability of this airfoil. By comparing the hydraulic performances of the two pumps obtained from the experiments, and the cavitation performance and flow field of the two pumps obtained from numerical simulations, it was found that AA blades can improve both the hydraulic and cavitation performances under a low flow rate and near the best efficiency flow point(BEP), whether in forward or reverse operation for the bi-directional axial-flow pump. Furthermore, the hydraulic performance of the AA blade pump declines sharply in a large flow rate compared to that of the SA blade pump. The location and composition of the inhomogeneous flows inside the impellers of the two pumps are similar. However, the SA blades work on fluid, mainly at the front half of the blades, which is a distinctive feature from the AA blades and may be a universal phenomenon in all SA-type blades.

Computational Investigation of Blade slotting on a High-Load Low-Pressure Turbine Profile at various Reynolds Numbers:Part Ⅰ——Slotting Scheme's Verification

Boundary layer separation and reattachment is often an unavoidable feature of low pressure (LP) turbine,one of the main causes of this phenomenon is the high altitude low Reynolds number experienced by the modern LP turbine stage in aero-engine.Although an excellent turbine airfoil design can avoid flow separation on certain extent,but within flight envelope,LP turbine's characteristic Reynolds number may varied greatly,so it will be still under the risk of the presence of separation bubble.In this two parts paper a new concept of slotted-blade was raised to testify the gain of the blade slotting.A high aerodynamic loading LP turbine blade IET-LPTA was under investigated with different Reynolds number.Computational results reveal that the blade slotting could be a way of choice to suppress separation bubble and reduce profile loss under the condition of low Reynolds number,although its position and geometry need to be further investigated.

The C2H2 zinc-finger protein LACKING RUDIMENTARY GLUME 1 regulates spikelet development in rice

Rice(Oryza sativa)spikelets are a unique inflorescence structure and their development directly determines grain size and yield.Although many genes related to spikelet development have been reported,the molecular mechanisms underlying this process have not been fully elucidated.In this study,we identified a new recessive rice mutant,lacking rudimentary glume 1(lrg1).The lrg1 spikelets only formed one rudimentary glume,which,along with the sterile lemmas,was homeotically transformed into lemma-like organs and acquired lemma identity.The transition from the spikelet to the floral meristem was delayed in the lrg1 mutant,resulting in the formation of an ectopic lemma-like organ between the sterile lemma and the terminal floret.In addition,we found that the abnormal lrg1 grain phenotype resulted from the alteration of cell numbers and the hull size.LRG1 encodes a ZOS4-06-C2H2 zinc-finger protein with the typical EAR motifs,and is expressed in all organs and tissues.LRG1 localizes to the nucleus and can interact with the TOPLESS-RELATED PROTEINs(TPRs)to repress the expressions of their downstream target genes.Taken together,our results reveal that LRG1 plays an important role in the regulation of spikelet organ identity and grain size.

Analysis of Internal Cooling Geometry Variations in Gas Turbine Blades

The present investigation analyzes the effects of major geometrical modifications to the interior of a convectioncooled gas turbine rotor blade. The main focus lies on the flow of the leading edge channels and the impact on theheat transfer. An experimental approach is performed with flow visualization via paint injection into water. Alsonumerical calculations are carried out in two sets, on the one hand water calculations accompanying the experimentsand on the other hand conjugate heat transfer calculations under realistic engine conditions. The latter calculationsare still ongoing delivering preliminary results.Five geometry configurations are investigated, three of them with differing turbulator arrangements in the leadingedge channels. The operating point of the base configuration is set to Re = 50,000 at the inlet while for the modifiedgeometries the pressure ratio is held constant compared to the base.Among several investigated configurations one could be identified that leads to a heat transfer enhancement inone leading edge channel 7 % larger compared to the base.