Object segmentation and labeling by learning from examples

We propose a system that employs low-level image segmentation followed by color and two-dimensional (2-D) shape matching to automatically group those low-level segments into objects based on their similarity to a set of example object templates presented by the user. A hierarchical content tree data structure is used for each database image to store matching combinations of low-level regions as objects. The system automatically initializes the content tree with only "elementary nodes" representing homogeneous low-level regions. The "learning" phase refers to labeling of combinations of low-level regions that have resulted in successful color and/or 2-D shape matches with the example template(s). These combinations are labeled as "object nodes" in the hierarchical content tree. Once learning is performed, the speed of second-time retrieval of learned objects in the database increases significantly. The learning step can be performed off-line provided that example objects are given in the form of user interest profiles. Experimental results are presented to demonstrate the effectiveness of the proposed system with hierarchical content tree representation and learning by color and 2-D shape matching on collections of car and face images.     

2D/3D Shaped Radiation Patterns of Sunflower and Conformal Antenna Arrays Using Phase Synthesis

2D and 3D beam synthesis from different antenna array arrangements are investigated in this paper. Planar sunflower, conformal cylinderical and spherical helical array arrangements are studied. The particle swarm optimization (PSO) technique is used to predict the phase distribution on the array elements. The beam synthesis is achieved by comparing the array factor with a predetermined mask with both upper and lower limits according to the intented application requirements. Different 2D and 3D masks are used in beam synthesis as pencil, flat-top, and cosecant single beam are predicted. The planar sunflower antenna array is investigated due to its high gain, low side-lobe level (SLL) below ??20 dB and its compact size. The phase distribution of sunflower array is estimated using PSO to radiate dual-beams in different planes. Dual-beam with pencil, flat-top, and cosecant beams are obtained with different half-power beam widths. 3D conformal antenna arrays of cylindrical and spherical helical arrangements are studied. Each 3D conformal array consists of four arms shifted in position by 90° orintation angle. Each arm is designed to radiate single beam in a specific direction. Four-beams are considered to radiate in the directions of θ_1,2,3,4?=?30°, and ?₁?=?0°, ?₂?=?90°, ?₃?=?180°, and ?₄?=?270° with SLL optimized below ??17 dB. The array arrangements analysis is based on the array theory formulation, through the implemention of the estimiated equation using a home programmed MATLAB code.

     

Ion adsorption studies of micro and nano acrylic fibers modified by ethanolamine

Micro and nano polyacrylonitrile fibers were modified to polyacrylonitrile‐monoethanolamine (PAN‐MEA) through reaction PAN with ethanolamine. The modified PAN fiber was prepared by conversion nitrile groups into hydroxyle groups using ethanolamine solution with different concentration under refluxing at 91°C. Modified raw acrylic fibers (RAF) with submicrometer diameters ranging from 120 to 300 nm were produced using electrospinning in N,N‐dimethyl formamide (DMF). The PAN‐MEA micro and nano fibers were examined as chelating material in a series of batch adsorption experiments for removal of Cu (II), Pb (II) and Ni (II) ions. The fiber structure has been investigated by different experimental techniques of characterization such as Fourier transform infrared spectroscopy (FT‐IR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Also, the physical and mechanical properties has been investigated in this study. Nano fibers show adsorption metal ions more than the usual fiber because of high ratio of surface to mass.     

Determination of biogenic amines in selected Malaysian food

The biogenic amines tryptamine (TRP), putrescine (PUT), histamine (HIS), tyramine (TYR) and spermidine (SPD) were determined in 62 selected food items commonly consumed in Malaysia. This include the local appetisers “budu” and “cincalok”, canned fish, salt-cured fish, meat products, fruit juice, canned vegetables/fruits and soy bean products. After the aqueous extraction, the samples were derivatised with dansyl chloride before analysing using reversed phase HPLC with UV detection. Mean levels of TRP, PUT, HIS, TYR and SPD in eight budu samples were 82.7, 38.1, 187.7, 174.7 and 5.1 mg kg⁻¹, respectively. The main biogenic amines found in cincalok were PUT, HIS and TYR where the mean values were 330.7, 126.1 and 448.8 mg kg⁻¹, respectively. With the exception of “pekasam” and “belacan”, significantly lower levels of biogenic amines were found in canned fish and salt-cured fish samples. Non detectable or low levels of biogenic amines were found in meat, fruit juice and canned vegetables/fruit samples.     

Structure and properties of nylon-6/amino acid modified nanoclay composite fibers

Biodegradable amino acid modified nanocaly was applied to produce nylon-6/nanoclay composite fibers using melt blending and melt spinning processes. Field emission scanning electron microscopy images showed that the surface of composite fibers was uniform and free from defects. Layer spacing of modified nanoclay was increased due to the penetration of polymer molecules into clay layers. Crystallinity, γ crystalline percentage and total molecular orientation of composite fibers were higher in comparison to neat nylon-6 fibers, as revealed by WAXD and birefringence measurements. Tensile strength of composite fibers was lower when compared to neat nylon-6 fibers. This may be attributed to some aggregation of nanoclay and its weakening effect. Melting and glass transition temperature of composite fiber was decreased due to the addition of modified nanoclay, indicating the formation of γ crystals and also breaking of some hydrogen bonds between the polymer molecules and the formation of new hydrogen bonds between the modified clay and the polymer molecules.     

Antiproliferative and antioxidative activities of cuttlefish (<Emphasis Type="Italic">Sepia pharaonis</Emphasis>) protein hydrolysates as affected by degree of hydrolysis

Bioactivities (including antioxidative and antiproliferative properties) of cuttlefish mantle protein hydrolysates (CPH) with the degree of hydrolysis (DH) of 20.9, 25.5, 30.6, 35.3 and 40.6% (shortened as 20, 25, 30, 35 and 40%, respectively) prepared using alcalase were evaluated. The results indicated that the CPH with 20, 30 and 40% DH showed the greatest activity against DPPH radical scavenging [5.2 µmol TE (torolox equivalent)/g sample], reducing power (0.4 absorbance at 700 nm) and total antioxidant capacity (0.6 mg ascorbic acid equivalent/g sample), which were 2.5, 6.5 and 13.8 times higher than the cuttlefish mantle protein isolate (CPI), respectively. The CPH with the DH of 20% had the highest effect against MDA-231 and T47D cancer cell lines with growth inhibition of 78.2 and 66.2%, which were 6.5 and 6 times higher activities compared to the CPI, respectively. The amino acid profile of CPH indicated that glutamine (15.7%) and asparagine (10.9%) were predominant.     

Electro-conductivity,bioactivity and UV protection of graphene oxide-treated cellulosic/polyamide fabric using inorganic and organic reducing agents

Here, graphene oxide (GO) was treated on the cellulosic/polyamide fabric reduced with various inorganic and organic compounds and compared the color changes, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, electrical resistivity, antibacterial/antifungal and ultraviolet protection properties. The graphite oxide was first synthesized using graphite and sonicated to obtain GO. It was then dissolved in distilled water along with cetyltrimethylammonium bromide (CTAB) to prepare a stable solution for long-time adsorbing more and uniform GO on cellulosic/polyamide fabric through exhaustion method. The GO-treated fabric was reduced to reduced graphene oxide (rGO) with inorganic and organic reducing agents including sodium dithionite with and without sodium hydroxide and dopamine hydrochloride at various temperatures. More fabricated GO reduced to rGO at higher temperature using dopamine produced lower electrical resistance. The antimicrobial activities of various samples were tested against two Gram-negative bacteria, E. coli and P. aeruginosa, two Gram-positive bacteria, S. aureus and E. faecalis and one eukaryotic fungus C. albicans. Ultraviolet protection was examined through reflectance spectra showed no UV transmittance from most of the treated fabrics. Further, CTAB was effective to load more GO on the fabric improved electrical resistance and higher antibacterial properties using both reducing agents.