Laser Scanning Method Research Articles

Ranunculus penicillatus in Norden

Twenty‐one populations of Ranunculus subgenus Batrachium (Ranunculaceae) from central Jutland, Denmark, were studied in the field and sampled for cytological, morphological and embryological investigation; for embryology the confocal laser scanning method (CLSM) was used. Six taxa were represented: R. penicillatus ssp. penicillatus and ssp. pseudofluitans, R. aquatilis var. aquatilis, R. peltatus ssp. peltatus and ssp. baudotii and R. circinatus. The main aim was to determine whether R. penicillatus occurs in the area. 14 of the 21 populations were referred to R. penicillatus; all 14 were tetraploid, though a few triploid plants were also found in two of these populations. Some populations show characteristic features of hybrid origin. These have, however, found a niche in swift rivers in west‐central Jutland, reduction in fertility being compensated for by the dominant asexual mode of reproduction, and new parts of the river systems have continually been invaded. They are accorded taxonomic rank, the heterophyllous populations being treated as ssp. penicillatus and the homophyllous populations as ssp. pseudofluituns. Accordingly, R. penicillatus is represented in Denmark and thus in Norden. Flora Nordica Notes no. 7.

Effect of anisotropy on microellipsometry in the [formula omitted] system

Electrochemical in situ ellipsometry with a focused laser beam (microellipsometry) is used to determine properties of oxide layers on single grains of Ti. The data for δ and Ψ differ from grain and also a strong dependence on the sample rotation around the surface normal occurs. This is due to the anisotropy of the Ti TiO 2 system. The measurements deliver information about the epitaxy of oxide layer formation and the orientation of the substratum's optical axis, which is proved by measurements on well-oriented single crystals. A method for data interpretation is presented which possibly allows the determination of oxide growth rates on Ti single grains despite their anisotropy. Measurements with microreflection spectroscopy and a photocurrent laser-scanning method confirm the microellipsometric results.

Novel nucleolar and nuclear morphology in a vincristine-dependent human leukemia cell line (L 100)

Acquired resistance to chemotherapeutic drugs by tumor cells is an important obstacle to effective therapy of human malignancy. We now describe a vincristine (VCR)-induced multidrug-resistant (MDR) human acute lymphatic leukemia cell line, the sustained in vitro growth of which is dependent on vincristine. The doubling time for parental drug-sensitive cells (L 0) is 40.2 ± 13.2 h and for the MDR subline (L 100) 62.5 ± 11.3 h. L 100 cells have similar dG 2 and mitotic phase to parental cells, express the MDR phenotype, and are characterized by novel morphologic features with multilobulated nuclei and multiple small nucleoli. Compared with l 0 cells which have 2–3 nucleoli per cell, L 100 cells have 7–8 nucleoli per cell. Average nucleolar area is 11.3 ± 7.3 μm 2 for L 0 and 2.5 ± 2.4 μm 2 for L 100 cells determined by the laser scanning method. The striking morphologic abnormalities of L 100 cells suggest a drug-induced cytoskeletal abnormality. The relationship of these abnormalities to the VCR growth dependence of L 100 Cells is discussed.

Roughness of soil fracture surfaces as a measure of soil microstructure

SUMMARYThe examination of soil fracture surfaces that are created under tensile stress may reveal a great deal about the internal structural condition of the soil. A simple technique for quantifying the roughness of soil fracture surfaces from a measurement of their topography in cross‐section is described. The technique involves calculating the standard deviation of the differences between the measured elevations of soil fracture surfaces and their corresponding running‐mean values. The standard deviation, σR, is used as a measure of the fracture surface roughness. Advantages of this technique over others are discussed.Two methods for measuring the topography of soil fracture surfaces are presented: a bisection (single transect) method, and a laser scanning (multiple transects) method. The laser scanning method is to be preferred because it requires no sample preparation and enables greater and more rapid replication. Also, fracture surfaces created by applying direct tension in the hands produced values of σR that were statistically indistinguishable from those created using indirect tension in a loading frame. This result makes the technique of fracture surface analysis usable for both laboratory as well as field investigations of soil structure.An example of the technique is presented to illustrate the role that air‐filled pores play in the brittle fracture of unsaturated soil (air‐filled pores are closer together in drier soils and further apart in wetter soils.) A strong positive linear correlation was found between the gravimetric water content, w and σR of natural soil clods, which supports the contention that brittle fracture of unsaturated soils under tensile stress occurs at least partly because of the propagation of air‐filled pores.

Investigation of the structure of stratified flows by the method of laser scanning

Investigation of the structure of stratified flows by the method of laser scanning

Laser Scanning Method for Guidance of Field Machinery

ABSTRACT Alaser scanning device for guidance of field machinery was designed, constructed and tested. Triangulational positioning is effected with the aid of a single laser source a single detection unit and two scanning mirrors. Test results were better than the predicted theoretical accuracy. This technology is applicable — with minor changes — for measurement of a 400m x 400m field with accuracy better than 15 cm.

Determination of the two-dimensional distribution of potentials in integrated circuits by the laser scanning method

Experimental contactless optical measurements were made of the electrical potentials at points inside integrated circuits utilizing semiconductors exhibiting the electrooptic effect. The method developed had a voltage measurement sensitivity of 0.1 V. For the first time a two-dimensional image of the structure of a semiconductor represented by the potential contrast was obtained by the laser scanning method.

Sensors in industrial metrology

Industrial metrology is concerned with sensors to measure movement of machine tool parts and monitor tool wear and the dimensions of artefacts in machining centres, sensors for robots in flexible manufacturing systems, sensors to gauge mating parts for selective assembly or allowing for interchangeability, and sensors for inspection and testing of assembled or part-assembled products. The author reviews the subject and emphasises significant advances, from the use of resonant sensor systems, edge-sensing profilers and methods of laser scanning, to acoustic emission techniques, imaging systems and the scanning tunnelling microscope.

レーザスキャニング法による熱延鋼板の形状測定

レーザスキャニング法による熱延鋼板の形状測定

Crosstalk Measurements On A Linear Array Of Deep U-Groove Isolated Silicon Photodiodes

We have made crosstalk measurements on our U-groove isolated photodiode array by two independent techniques, an electrical measurement method and a laser scanning method. These two methods are shown to corre-late with each other. The crosstalk between two adjacnt pixels of the U-groove isolated array was below 5 X 10-4, which compared favorably to the value of 10-1 for the conventional diffusion junction photodiode array. Also, the effective diffusion length of the photogenerated carriers was measured to be 10µm in the N-region and 6 um in the top P-region. The advantages of the detector isolation technique for optical signal processing are presented.

Moiré topography using developed recording methods

Where moiré topography is used to record the shape of objects of approximately cylindrical form or that of a series of such objects, a scanning method with a slit camera can be employed. One such method takes photographs by combining conventional shadow type and projection type moiré topography with a slit camera. Laser methods of line projection combined with a scanning method developed from the projection type of moiré topography are also utilised. The main features of the latter method are that it is not affected by any diffraction effect caused by the grid and that highly accurate recording can be achieved with excellent image quality using the properties of the laser beam. Another distinct advantage is that it is capable of recording the shape of a self-luminous object without contacting by selection of laser wavelenghts and matching optical filters. The laser scanning method can therefore be considered to have considerable potential for future applications.