A new technique based on the statistical autoregressive (AR) model has recently been developed as a solution to signal-to-noise (SNR) estimation in scanning electron microscope (SEM) images. In the present study, we propose to cascade the Lagrange time delay (LTD) estimator with the AR model. We call this technique the mixed Lagrange time delay estimation autoregressive (MLTDEAR) model. In a few test cases involving different images, this model is found to present an optimum solution for SNR estimation problems under different noise environments. In addition, it requires only a small filter order and has no noticeable estimation bias. The performance of the proposed estimator is compared with three existing methods: simple method, first-order linear interpolator, and AR-based estimator over several images. The efficiency of the MLTDEAR estimator, being more robust with noise, is significantly greater than that of the other three methods.
Fat is an important ingredient in baking products and it plays many roles in providing desirable textural properties of baking products, particularly biscuit. In this study, the effect of fat types on dough rheological properties and quality of semi-sweet biscuit (rich tea type) were investigated using various techniques. Texture profile and extensibility analysis were used to study the dough rheology, while three-point bend test and scanning electron microscopy were used to analyse the textural characteristics of final product. TPA results showed that the type of fat significantly influenced dough textural properties. Biscuit produced with higher solid fat oil showed higher breaking force but this was not significantly different when evaluated by sensory panel. Scanning electron microscopy showed that biscuit produced with palm mid-fraction had an open internal microstructure and heterogeneous air cells as compared to other samples.
The morphological data of Malesian Lejeunea is described in detail based on examination of about 600 fresh specimens and 1500 herbarium specimens of Lejeunea from other herbaria. Scanning electron microscopy (SEM) images and photographs illustrating the characters of Lejeunea are presented.
This is the extended project by introducing the modified dynamic range histogram modification (MDRHM) and is presented in this paper. This technique is used to enhance the scanning electron microscope (SEM) imaging system. By comparing with the conventional histogram modification compensators, this technique utilizes histogram profiling by extending the dynamic range of each tile of an image to the limit of 0-255 range while retains its histogram shape. The proposed technique yields better image compensation compared to conventional methods.
Histological observation and scanning electron microscopy analyses in Dendrobium Bobby Messina indicates the cellular process of cryopreserved protocorm-like bodies (PLBs) was different comparative to non-cryopreserved PLBs. The cellular process was not only modified by the freezing and thawing effect but also due to the dehydration process itself during the cryopreservation procedure. Histological observation in Dendrobium Bobby Messina in encapsulation-dehydration method indicated that the degree of plasmolysis causes more cellular changes to the cryopreserved PLBs comparative to non-cryopreserved and stock culture PLBs. These results revealed higher amount of homogenous cell population and denser cytoplasm in cryopreserved PLBs. Histological analysis also revealed more voluminous nucleus in cryopreserved PLBs comparative to non-cryopreserved PLBs and PLBs stock culture. In contrast, scanning electron microscope analysis showed severe damages in cryopreserved PLBs and non-cryopreserved PLBs comparative to the PLBs stock culture which in return could be the possible reason of no regrowth in encapsulation-dehydration method. Damages incurred were on top part, side part, and at the stomata of the PLBs. Histological observation and scanning electron microscopy analyses in Dendrobium Bobby Messina indicates that the degree of plasmolysis causes changes in the cellular process of PLBs from cryopreserved PLBs was different comparative to non-cryopreserved PLBs.
An improvement to the previously proposed Canny optimization technique for scanning electron microscope image colorization is reported. The additional process is adaptive tuning, where colour tuning is performed adaptively, based on comparing the original luminance values with calculated luminance values. The complete adaptive Canny optimization technique gives significantly better mechanical contrast on scanning electron microscope grey-scale images than do existing methods.
Interpolation techniques that are used for image magnification to obtain more useful details of the surface such as morphology and mechanical contrast usually rely on the signal information distributed around edges and areas of sharp changes and these signal information can also be used to predict missing details from the sample image. However, many of these interpolation methods tend to smooth or blur out image details around the edges. In the present study, a Lagrange time delay estimation interpolator method is proposed and this method only requires a small filter order and has no noticeable estimation bias. Comparing results with the original scanning electron microscope magnification and results of various other interpolation methods, the Lagrange time delay estimation interpolator is found to be more efficient, more robust and easier to execute.
This work represents a study to investigate the mechanical properties of longitudinal basalt/woven-glass-fiber-reinforced unsaturated polyester-resin hybrid composites. The hybridization of basalt and glass fiber enhanced the mechanical properties of hybrid composites. The unsaturated polyester resin (UP), basalt (B) and glass fibers (GF) were fabricated using the hand lay-up method in six formulations (UP, GF, B7.5/G22.5, B15/G15, B22.5/G7.5 and B) to produce the composites, respectively. This study showed that the addition of basalt to glass-fiber-reinforced unsaturated polyester resin increased its density, tensile and flexural properties. The tensile strength of the B22.5/G7.5 hybrid composites increased by 213.92 MPa compared to neat UP, which was 8.14 MPa. Scanning electron microscopy analysis was used to observe the fracture mode and fiber pullout of the hybrid composites.
Micro-turning is a micro-mechanical cutting method used to produce small diameter cylindrical parts. Since the diameter of the part is usually small, it may be a little difficult to improve the surface quality by a second operation, such as grinding. Therefore, it is important to obtain the good surface finish in micro turning process using the ideal cutting parameters. Here, the multi-objective optimization of micro-turning process parameters such as cutting speed, feed rate and depth of cut were performed by response surface method (RSM). Two important machining indices, such as surface roughness and material removal rate, were simultaneously optimized in the micro-turning of a Ti6Al4V alloy. Further, the scanning electron microscope (SEM) analysis was done on the cutting tools. The overall results depict that the feed rate is the prominent factor that significantly affects the responses in micro-turning operation. Moreover, the SEM results confirmed that abrasion and crater wear mechanism were observed during the micro-turning of a Ti6Al4V alloy.
Currently, research in composite materials is being directed at using natural fibers instead of synthetics fibers. The use of natural fibers, derived from annually renewable resources, as reinforcing fibers in matrix provides positives environmental benefits with respect to ultimate disposability and raw material utilization. Natural fiber offers an alternative to the technical reinforcing fibers because of their low density, good mechanical performance, ultimate availability and disposability. Modifying the fiber surface by using chemical treatment can enhance bond strength between fiber and matrix. Chemical treatment also an effective way to clean the fiber surface, chemically modify the surface and increase the surface roughness. Surface analyses on fiber for before and after treatment were investigated using scanning electron microscopy (SEM).
The microstructure, tensile fracture and creep fracture of as-cast beta phase contained γ-TiAl with nominal composition of Ti-48Al-4Cr (at.%) was investigated. The effect of beta phase on tensile and creep strength was determined from fracture analysis. Tensile test were performed at room temperature whereas constant load tensile creep test were performed at temperature 800 0 C and initial stress of 150MPa. Initial as-cast microstructure, microstructure and fracture surface after tensile and creep test were examined using scanning electron microscopy technique. Analysis shows brittle fracture after room temperature tensile test whereas ductile fracture after high temperature creep test. The role of beta phase was discussed. It is concluded that beta phase is sensitive to temperature and detrimental at both room and high temperature.
L18 orthogonal array in mix level of Taguchi robust design method was carried out to optimize experimental conditions for the preparation of polymer blend composite. Tensile strength and neutron absorption of the composite were the properties of interest. Filler size, filler loading, ball mixing time and dispersion agent concentration were selected as parameters or factors which are expected to affect the composite properties. As a result of Taguchi analysis, filler loading was the most influencing parameter on the tensile strength and neutron absorption. The least influencing was ball-mixing time. The optimal conditions were determined by using mix-level Taguchi robust design method and a polymer composite with tensile strength of 6.33 MPa was successfully prepared. The composite was found to fully absorb thermal neutron flux of 1.04 x 105n/cm2/s with only 2 mm in thickness. In addition, the filler was also characterized by scanning electron microscopy (SEM) and elemental analysis (EDX).
The chemical composition and anatomical characteristics on lignin distribution of rattan waste were analyzed to determine its suitability to be used in binderless board fabrication. The chemical composition was analyzed by using TAPPI methods. Observation and determination of lignin distribution and board structure were executed by using optical microscopy (OM) and scanning electron microscope (SEM). High amount of hemicellulose, cellulose and lignin content found in rattan waste chemical composition is seen to help in binderless board fabrication. The micrographs revealed that the rattan has fine structural construction that helps in producing good qualities of binderless boards with particular manufacturing parameters.
Ultrastructural study was carried out 2 groups of pollen with numerous, arranged and spirals on convex. Five species was studied; Desmos chinensis Lour. Fl., Desmos cochinchinensis Lour Fl. , Desmos dumonsus (Roxb.) Safford. , Desmos dunalii (Hk. F. et Th.) Safford. and Desmos dasymaschalus (Bl.) Safford. Pollen was collected from UKM Herbarium specimens and fresh specimen was collected at difference area in the Malaysia. They were acetolysis and dried by CPD method. Parameter studied via scanning electron microscope are mounted pollen, were stamen material; shape, P/E, size, surface structure and calpus ornamentation. Results obtained showed that pollen was inaperturate with needle structure and solitary globus. The morphology of pollen grains of all the species is presented and an identification key base on scanning electron microscope observations is tested.
Pollens and seeds of Hypoestes and Rhinacanthus collected from different field localities in Taiz and Soqotra Island, Yemen were investigated by using light and scanning electron microscopes. Pollen grains of Hypoestes were prolate in equatorial view, lobate trigonal to lobate circular in polar view whereas those of Rhinacanthus were subspheroidal and rounded trigonal in polar view. The aperture was tricolporate and exine ornamentation was coarsely reticulate for all species in the two genera. Scanning electron microscopy and morphological observations showed that mature dry seeds of Hypoestes and Rhinacanthus have various sizes and shapes, the surface ornamentations observed were reticulate to cristate, an addition to the tuberculum and papillae. The three Hypoestes species differ in the seed structure which are useful for identification and their high structural diversity provides an important taxonomic value for species differentiation.
Poly-vinyl-pyrrolidone (PVP)/polyaniline based surface acoustic wave (SAW) sensors were fabricated and characterized and their performances towards hydrogen gas were investigated. The PVP/polyaniline fibers composite were prepared by electrospinning of the composite aqueous solution deposited directly onto the active area of SAW transducers. Via scanning electron microscopy (SEM), the morphology of the deposited nanostructure material was observed. From the dynamic response, frequency shifts of 6.243 kHz (1% H2) and 8.051 kHz (1% H2) were recorded for the sensors deposited with PVP/ES and PVP/EB, respectively.
A number of n-type Si (100) samples were prepared into porous structures via electrochemical etching process, using an electrolyte solution; HF and ethanol. The morphological properties of the samples were observed under scanning electron microscope measurement. The results showed that the pore density, pore uniformity distribution and pore size of the porous Si samples increased with time of etching. In the next stage, H2O2 was introduced into the electrolyte solution in order to investigate its effect on the morphological properties of the porous Si. From the experiment, we found that H2O2 gave finer porous structure with highly symmetrical cubic shape on the surface. Besides, H2O2 promoted smoother surface of the pore walls. Hence, the results showed that such porous Si structure could be used as a better substrate for the subsequent layer, in particular for the growth of cubic material.
Pollen morphology of 24 species of Vatica L. had been investigated using light and scanning electron microscopes. Vatica is a stenopalynous genus, the pollens are radially symmetrical, isopolar, subprolate to suboblate sometimes prolate rarely oblate, all tricolpate. Exine ornamentation varies from thin to medium reticulate. On the basis of pollen shape two groups of Vatica have been recognized. Within the genus pollen diversity is valuable for identification and delimiting species.
A comparative leaf micromorphological study of Melastoma malabathricum, M. malabathricum var. alba and M.
sanguineum (Melastomataceae) was carried out by scanning electron microscope. Characters such as epidermal cell
shape, trichomes and stomatal type and distribution were observed. Non-glandular trichomes are present in all species
examined. The stomata are all of paracytic type and dispersed randomly over the whole abaxial surface. The patterns of
surface sculpturing and outer stomatal rim are unique in all the species examined. Leaf micromorphology has significant
taxonomic value in the genus Melastoma and the present study has added some new taxonomic information for the genus
An improvement to the previously proposed adaptive Canny optimization technique for scanning electron microscope image colorization is reported. The additional feature, called pseudo-mapping technique, is that the grayscale markings are temporarily mapped to a set of pre-defined pseudo-color map as a mean to instill color information for grayscale colors in chrominance channels. This allows the presence of grayscale markings to be identified; hence optimization colorization of grayscale colors is made possible. This additional feature enhances the flexibility of scanning electron microscope image colorization by providing wider range of possible color enhancement. Furthermore, the nature of this technique also allows users to adjust the luminance intensities of selected region from the original image within certain extent.