14,855 research outputs found
Bow-Tie Microstrip Antenna Design
In this paper, the bow-tie microstrip antennas have been designed with two different angles of 40° and 80°. An investigaton on the effect of the angle to the return loss and radiation patterns had been carried out. The impedance matching network with the niicrostrip transmission line feeding was used in this study. Simulation and measurement results for the return loss and radiation patterns were presented
Sandpiles on multiplex networks
We introduce the sandpile model on multiplex networks with more than one type
of edge and investigate its scaling and dynamical behaviors. We find that the
introduction of multiplexity does not alter the scaling behavior of avalanche
dynamics; the system is critical with an asymptotic power-law avalanche size
distribution with an exponent on duplex random networks. The
detailed cascade dynamics, however, is affected by the multiplex coupling. For
example, higher-degree nodes such as hubs in scale-free networks fail more
often in the multiplex dynamics than in the simplex network counterpart in
which different types of edges are simply aggregated. Our results suggest that
multiplex modeling would be necessary in order to gain a better understanding
of cascading failure phenomena of real-world multiplex complex systems, such as
the global economic crisis.Comment: 7 pages, 7 figure
Safely dissolvable and healable active packaging films based on alginate and pectin
Extensive usage of long-lasting petroleum based plastics for short-lived application such as packaging has raised concerns regarding their role in environmental pollution. In this research, we have developed active, healable, and safely dissolvable alginate-pectin based biocomposites that have potential applications in food packaging. The morphological study revealed the rough surface of these biocomposite films. Tensile properties indicated that the fabricated samples have mechanical properties in the range of commercially available packaging films while possessing excellent healing effciency. Biocomposite films exhibited higher hydrophobicity properties compared to neat alginate films. Thermal analysis indicated that crosslinked biocomposite samples possess higher thermal stability in temperatures below 120 °C, while antibacterial analysis against E. coli and S. aureus revealed the antibacterial properties of the prepared samples against different bacteria. The fabricated biodegradable multi-functional biocomposite films possess various imperative properties, making them ideal for utilization as packaging material
Waiting time dynamics of priority-queue networks
We study the dynamics of priority-queue networks, generalizations of the
binary interacting priority queue model introduced by Oliveira and Vazquez
[Physica A {\bf 388}, 187 (2009)]. We found that the original AND-type protocol
for interacting tasks is not scalable for the queue networks with loops because
the dynamics becomes frozen due to the priority conflicts. We then consider a
scalable interaction protocol, an OR-type one, and examine the effects of the
network topology and the number of queues on the waiting time distributions of
the priority-queue networks, finding that they exhibit power-law tails in all
cases considered, yet with model-dependent power-law exponents. We also show
that the synchronicity in task executions, giving rise to priority conflicts in
the priority-queue networks, is a relevant factor in the queue dynamics that
can change the power-law exponent of the waiting time distribution.Comment: 5 pages, 3 figures, minor changes, final published versio
The architecture of complex weighted networks
Networked structures arise in a wide array of different contexts such as
technological and transportation infrastructures, social phenomena, and
biological systems. These highly interconnected systems have recently been the
focus of a great deal of attention that has uncovered and characterized their
topological complexity. Along with a complex topological structure, real
networks display a large heterogeneity in the capacity and intensity of the
connections. These features, however, have mainly not been considered in past
studies where links are usually represented as binary states, i.e. either
present or absent. Here, we study the scientific collaboration network and the
world-wide air-transportation network, which are representative examples of
social and large infrastructure systems, respectively. In both cases it is
possible to assign to each edge of the graph a weight proportional to the
intensity or capacity of the connections among the various elements of the
network. We define new appropriate metrics combining weighted and topological
observables that enable us to characterize the complex statistical properties
and heterogeneity of the actual strength of edges and vertices. This
information allows us to investigate for the first time the correlations among
weighted quantities and the underlying topological structure of the network.
These results provide a better description of the hierarchies and
organizational principles at the basis of the architecture of weighted
networks
Korelasi pekali kekasaran kekar dengan sudut geseran puncak satah ketakselanjaran batuan syis, Semenanjung Malaysia (Correlation of joint roughness coefficient with peak friction angles of discontinuity planes of schists, Peninsular Malaysia)
Kekasaran permukaan amat mempengaruh tingkah-laku ricihan dan nilai sudut geseran puncak sesuatu satah
ketakselanjaran. Oleh yang demikian, kekasaran permukaan merupakan faktor yang penting yang perlu dinilai dalam
menentukan kestabilan struktur pengorekan dalam jasad batuan. Beberapa kaedah boleh digunakan untuk menentukan
kekasaran permukaan ketakselanjaran. Kertas ini memperkenalkan satu pendekatan yang mudah dalam bentuk dua rumus
polinominal yang boleh digunakan untuk mengkorelasi sudut geseran puncak ketakselanjaran (φp) batuan syis segar
dan terluluhawa sedikit dengan pekali kekasaran kekar, PKK. Rumus polinominal ini ialah φp= -0.022PKK2 + 3.21PKK
+ 28.1 untuk ketakselanjaran segar dan φp= -0.025PKK2 + 3.24PKK + 26.6 untuk ketakselanjaran terluluhawa sedikit.
Kedua-dua rumus ini memperlihatkan nilai pekali penentuan, R2 = 0.98. Hasil kajian ini menawarkan satu kaedah
alternatif penganggaran φp satah ketakselanjaran daripada nilai PKK yang diukur pada permukaan ketakselanjaran di
lapangan
A High-Fat Diet Enriched with Low Omega-6 to Omega-3 Fatty Acid Ratio Reduced Fat Cellularity and Plasma Leptin Concentration in Sprague-Dawley
This study was aimed to investigate the effects of dietary fatty acids on the accretion pattern of major fat pads, inguinal fat cellularity, and their relation with plasma leptin concentration. Forty Sprague-Dawley rats were randomly assigned into four groups and received the following diets for 22 weeks: (1) standard rat chow diet (CTRL), (2) CTRL + 10% (w/w) butter (HFAR), (3) CTRL + 3.33% (w/w) menhaden fish oil + 6.67% (w/w) soybean oil (MFAR), and (4) CTRL + 6.67% (w/w) menhaden fish oil + 3.33% (w/w) soybean oil (LFAR). Inguinal fat cellularity and plasma leptin concentration were measured in this study. Results for inguinal fat cellularity showed that the mean adipocyte number for the MFAR (9.2 * 105 ± 3.6) and LFAR (8.5 * 105 ± 5.1) groups was significantly higher (P<0.05) than the rest, while the mean adipocyte diameter of HFAR group was larger (P<0.05) (46.2 ± 2.8) than the rest. The plasma leptin concentration in the HFAR group was higher (P<0.05) (3.22 ± 0.32 ng/mL), than the other groups. The higher inguinal fat cellularity clearly indicated the ability of the polyunsaturated fatty acids (PUFA) and butter supplemented diets to induce hyperplasia and hypertrophy of fat cells, respectively, which caused adipocyte remodeling due to hyperleptinemia
Industrial building system : does it good for sustainable building? / S. Roshanfekr, N. M Tawil and N. A. Goh
Housing and building construction is an important principle in sustainable development. The industrialization of building systems has been found to be necessary due to several factors: the fast and continuing progress of
today’s world, the industrialization of many aspects of modern living, significant population growth, and the
inadequacy and incompetence of conventional construction methods particularly in dense housing situations. This paper investigates the relevance of these factors as the drivers for changing people’s habits and
perspectives toward building construction and to justify the introduction of industrialized construction approaches to replace the outdated conventional methods as well as the necessity to provide training in order to achieve product quality
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