Exploration of local surface geometry with minimum number of contact points and surface normal information

In this paper, we propose a method of exploring the surface geometry of an unknown object by touch. The method is based on the idea that a three-dimensional surface geometry can be reconstructed from two principal curvatures of the object which are estimated from three concurrent curves. First, the process to minimize the number of contact points is addressed for the approximation of an arbitrary curve, which uses normal vectors at the contact points. Then, an algorithm for reconstructing a three-dimensional local surface from four contact points, two of which can be used to compute a normal curvature, is presented. Lastly, our method is applied to cylindrical, spherical and planar objects in simulation and experiments for validation.     

Addition of gelatin enhanced gelation of corn–milk yogurt

Corn–milk yogurt set by a combination of sodium caseinate plus gelatin at concentrations of 0, 0.2, 0.4 and 0.6% (w/v) were studied. The quality of the gels was determined by measurement of acidity, syneresis, texture profile analysis, viscoelasticity, structure scanning electron microscope and microbiology. Texture profile analysis (TPA) showed that increasing levels of gelatin increased hardness, adhesiveness and springiness as well as the acidity of the products. Viscoelastic behaviour displayed similar trends to the TPA characteristics, the storage modulus was less frequency dependent than the loss modulus giving a loss tangent of 0.2 in the high gelatin systems, which might indicate a true gel system. The microstructure was dense and spongy-like with small air cells, in particular, those having a high concentration of gelatin (0.6%, w/v) gave a very firm structure which might impair palatability. The addition of a commercial gelatin at 0.4% (w/v) gave good acceptability for the product (little syneresis of the gels produced). While the gelatin used for this study had a bloom value of 246 g the authors acknowledge that a different commercial gelatin may well result in a different concentration being required.     

Comparative effect of overexpressed phaJ and fabG genes supplementing (R)-3-hydroxyalkanoate monomer units on biosynthesis of mcl-polyhydroxyalkanoate in Pseudomonas putida KCTC1639

phaJ and fabG genes encoding (R)-specific 2-enoyl-CoA hydratase and 3-ketoacyl-acyl carrier protein reductase, respectively, were cloned from Pseudomonas putida KCTC1639 and amplified in the parent strain to achieve oversupplementation of (R)-3-hydroxyalkanoate monomer units for the biosynthesis of medium-chain-length polyhydroxyalkanoate (mcl-PHA). The comparative effect of the overexpressed fabG and phaJ genes in P. putida KCTC1639 on the biosynthesis of mcl-PHA and the cell growth were elucidated. Overexpression of phaJ enhanced the biosynthesis of mcl-PHA, increasing its content and concentration from 18% to 27% and 0.38 to 0.51 g/l, respectively. Conversely, fabG overexpression tended to depress the biosynthesis of mcl-PHA, possibly due to the reversible conversion of (R)-3-hydroxyalkanoate monomer units into 3-ketoacyl-CoA.     

Distributed stream join query processing with semijoins

This paper addresses the distributed stream processing of window-based multi-way join queries considering the semijoin as a key join operator. In distributed stream processing, data streams arriving at remote sites need to be shipped to the processing site for query execution. This typically introduces high communication overhead. Our observation is that semijoin, effective in reducing communication overhead in distributed database query processing, can be also effective in distributed stream query processing. The challenge, however, lies in the streaming nature of the tuples, as it requires continuous and incremental processing of an unbounded sequence of tuples instead of one-time processing of a set of stored tuples. This paper describes our comprehensive work done to address the challenge. Specifically, we first propose a distributed stream join processing model that handles the issue of network delays introduced from the shipment of data streams, and allows for efficient batch processing. Then, based on the model, we propose join algorithms in a multi-way join case: first, one-way join algorithms for different combinations of join placement and join method and, then, multi-way join algorithms assuming linear join ordering. Regarding the join method, two distributed join methods are introduced: (1) simple join, in which full tuples are forwarded to the query processing site and (2) semijoin-based join, in which partial tuples are forwarded. A semijoin-based join can be executed with different possible semijoin strategies which incur different communication overheads. We present a complete set of join algorithms considering all possible semijoin strategies, and propose an optimization algorithm. The join algorithms are executed continuously in an incremental manner as tuples arrive, and never ship tuples redundantly. The optimization algorithm constructs an efficient multi-way join plan by using a greedy heuristic which adds to the plan one stream with the minimum join execution cost in each step. Through extensive experiments, we conduct comparative studies of the performance among the proposed one-way join algorithms and the efficiency of the generated plan between the optimization algorithm based on the greedy heuristic and the exhaustive search, respectively.     

Physico-mechanical and antimicrobial properties of gelatin film from the skin of unicorn leatherjacket incorporated with essential oils

Gelatin films incorporated with bergamot (BO) and lemongrass oil (LO) at various concentrations as glycerol substitute were prepared and characterised. Incorporation of BO and LO at 5–25% (w/w protein) resulted in the decreases in both tensile strength (TS) and elongation at break (EAB) of the films. Water vapour permeability (WVP) were decreased in LO incorporated films, while it was increased in film added with BO at level higher than 5% (P < 0.05). Film solubility and transparency values decreased, and the films had the lowered light transmission in the visible range when BO and LO were incorporated. Films incorporated with LO showed inhibitory effect in a concentration dependent manner against Escherichia coli, Listeria monocytogenes, Staphylococcus aureus and Salmonella typhimurium, but BO added film inhibited only L. monocytogenes and S. aureus. Films containing both BO and LO did not inhibit Pseudomonas aeruginosa. Significant change of molecular organisation and higher intermolecular interactions among gelatin molecules were found in the film structure as determined by FTIR. Thermo-gravimetric analysis (TGA) demonstrated that films added with BO and LO exhibited enhanced heat stability with higher degradation temperature, compared with control film. Scanning electron microscopic (SEM) images revealed the presence of micro-pores in the essential oil incorporated films, which contributed to physical properties of the resulting films. Thus, gelatin films incorporated with BO and LO can be used as active packaging, but the properties could be modified, depending on essential oil added.     

Real-time detection of changes in network with OpenFlow based on NetFPGA implementation

Sketch-based algorithms are extensively applied in a wide range of networking applications. This work develops the compact implementation of a system for detecting changes in traffic in real time with OpenFlow on a NetFPGA 1G (4 × 1G) platform. The system can monitor network traffic at a line rate of up to 4 Gbps with the required detection accuracy needed with limited memory on-board. The system utilizes a one-pass method to determine when the flow exceeds a predefined threshold. Based on the flow IDs identified, actions are issued immediately to switches to respond properly according to the OpenFlow protocol.     

Photodecomposition effects of graphene oxide coated on TiO2 thin film prepared by electron-beam evaporation method

Morphological, structural and photocatalytic properties of graphene oxide (GO)/TiO₂ thin-film deposited on quartz substrate were investigated. The TiO₂ film was prepared by electron-beam evaporation and the GO film by spin coating method. The photocatalytic activities of the GO/TiO₂ film were evaluated by photodecomposition of methylene blue. There was synergistic effect between TiO₂ and GO which causes a rapid photo-induced charge separation and the reduction of the recombination of electron-hole pairs under the UV-visible light irradiation. GO on TiO₂ film also promotes the properties of adsorption of the dye, photon scattering probability, and interacting surface area. As a result, it leads to the enhancement of the efficiency of the photodegradation in GO/TiO₂ film.