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151.
This paper proposes a distributed borrowing addressing (DIBA) scheme to solve problems of failure in address assignments resulting from limited tree depth and width when the distributed address assignment mechanism is used in a ZigBee/IEEE 802.15.4 wireless sensor network. DIBA is a method of borrowing addresses from neighbor nodes for newly entering nodes and assigning the borrowed addresses. Its network or sensing coverage can increase with almost the same overhead as the existing method. DIBA is a simple and lightweight means of addressing and routing, making it suitable for wireless sensor networks. Simulations showed that DIBA is a distributed addressing scheme with consistently excellent performance. 相似文献
152.
This research work focuses on the utilization of coconut shell powder (CSP) as filler in recycled polypropylene (rPP). Sodium Dedecyl Sulfate (SDS) was used as coupling agent in these composites. The effect of filler content and SDS on tensile properties, thermal properties, water absorption and morphology of rPP/CSP composites were investigated. In this study, modified rPP/CSP composites with SDS show significant increased tensile propertied, thermal stability, crystallinity and low water absorption compared unmodified rPP/CSP composites. Those improvements were contributed by the coupling effect of SDS. 相似文献
153.
154.
Nanogap Array Fabrication Using Doubly Clamped Freestanding Silicon Nanowires and Angle Evaporations
Han Young Yu Chil Seong Ah In‐Bok Baek Ansoon Kim Jong‐Heon Yang Chang‐Guen Ahn Chan Woo Park Byung Hoon Kim 《ETRI Journal》2009,31(4):351-356
We present a simple semiconductor process to fabricate nanogap arrays for application in molecular electronics and nano‐bio electronics using a combination of freestanding silicon nanowires and angle evaporation. The gap distance is modulated using the height of the silicon dioxide, the width of the Si nanowires, and the evaporation angle. In addition, we fabricate and apply the nanogap arrays in single‐electron transistors using DNA‐linked Au nanoparticles for the detection of DNA hybridization. 相似文献
155.
The corrosion behaviour and change of the phase fraction in welded 24Cr Duplex stainless steel was investigated for different chemical composition ranges of Mo contents. Filler metal was produced by fixing the contents of Cr, Ni, N, and Mn while adjusting the Mo content to 0.5, 1.4, 2.5, 3.5 wt%. The δ-ferrite fraction was observed to increase as the content of Mo increased. A polarisation test conducted in a salt solution, indicated the pitting corrosion potential increased continuously to 3.5 wt% Mo, while the corrosion potential changed most between 0.5 and 1.41 wt% Mo. The location of the pitting corrosion in 0.5 wt% Mo steel was randomly distributed, but it occurred selectively at the grain boundary between the γ- and δ-ferrite phases in 1.4, 2.5 and 3.5 wt% Mo steel. Energy dispersive X-ray spectroscopy mapping analysis showed that areas deficient in Cr, Mo, and Ni occurred around the grain boundary of the γ- and δ-ferrite phases. Non-metallic inclusions are thought to act as initiation points for the pitting corrosion that occurs in the salt solution initially as a result of the potential difference between the matrix structure and the incoherent inclusions. 相似文献
156.
Experimental values of the thermal conductivity and the thermal diffusivity of six pure liquid n-alkanes (C
n
H2n+2; n=5 to 10) and toluene are presented in the temperature range of –20 to 70°C under atmospheric or saturation pressure. Measurements were made with the transient hot-wire method, and in the analysis, the temperatures T
and T
(associated with both and ) were used. In the present work, the values of thermal diffusivity were corrected by the factors k
f (=1.0076 to 0.9892) for data sets obtained with different configurations of the experiment, in which the factors were determined by reference to the thermal diffusivity of n-heptane [=
s/(c
p
)s] at 298.15 K calculated from the volumic heat capacity (c
p
)s as a reference material for heat capacity and the experimentally obtained thermal conductivity
s. The uncertainty of the data is estimated to be 0.48% for the thermal conductivity (absolutely measured) and about 1.8% for the thermal diffusivity (with a coverage factor of k
p
=2; p=95%). 相似文献
157.
In this paper, we introduce a mathematical model to analyze pricing and service quality strategies for e-business companies providing information services to customers. The basic strategy considered in this paper is that a monopolistic e-business company provides free services to try to earn a profit by developing premium goods or services to market created by their free goods or services. It is a kind of versioning strategy where lower quality versions of information goods are provided free. And a direct network effect was also considered. And we tried to find the profit maximizing strategies for monopolistic e-business companies. As a result, the optimal quality and price for the premium goods or services can be obtained at the same level of the intensity of the direct network effect. And the exact term related with the network externality is derived and insights are demonstrated through numerical explorations. 相似文献
158.
Do‐Young Park Seong‐Eui Lee Young‐Mo Kim Jin‐Seok Kim Yong‐Seog Kim 《Journal of the Society for Information Display》2006,14(1):87-92
Abstract— In this study, the effects of diamond and AlN layers inserted beneath the phosphor layer of the rear plate of a PDP were investigated. The layers were formed via an osmotic‐pressure coating process. Macrocells and test panels were prepared to examine their effects on luminance and luminous efficacy. The results indicate that the layers primarily affect the glow‐discharge behavior and eventually enhance the luminous efficacy of the PDP, suggesting the possibile improvement in the performance of PDPs. 相似文献
159.
Deborah C. Blaine Seong Jin Park Randall M. German Pavan Suri 《Metallurgical and Materials Transactions A》2006,37(9):2827-2835
One of the current challenges facing the particulate materials industry is developing simple, accurate models to predict sintered
properties. Work-of-sintering concepts, where time-temperature integrals are used in such models, offer a solution to this
problem. In this study, the master sintering curve concept is applied to several powder metal systems: 17 to 4PH stainless
steel, 316L stainless steel, nickel, niobium, tungsten heavy alloys with two different compositions, and molybdenum. A detailed
explanation of the construction of these curves is given, including methods used to calculate the apparent activation energy
for sintering and to curve-fit experimental data to a sigmoid function describing the master sintering curve. Discussion of
the results shows that the master sintering curve can be applied to powder metal systems, even those that use liquid phase
during sintering. 相似文献
160.
In mobile communications, a class of variable‐complexity algorithms for convolutional decoding known as sequential decoding algorithms is of interest since they have a computational time that could vary with changing channel conditions. The Fano algorithm is one well‐known version of a sequential decoding algorithm. Since the decoding time of a Fano decoder follows the Pareto distribution, which is a heavy‐tailed distribution parameterized by the channel signal‐to‐noise ratio (SNR), buffers are required to absorb the variable decoding delays of Fano decoders. Furthermore, since the decoding time drawn by a certain Pareto distribution can become unbounded, a maximum limit is often employed by a practical decoder to limit the worst‐case decoding time. In this paper, we investigate the relations between buffer occupancy, decoding time, and channel conditions in a system where the Fano decoder is not allowed to run with unbounded decoding time. A timeout limit is thus imposed so that the decoding will be terminated if the decoding time reaches the limit. We use discrete‐time semi‐Markov models to describe such a Fano decoding system with timeout limits. Our queuing analysis provides expressions characterizing the average buffer occupancy as a function of channel conditions and timeout limits. Both numerical and simulation results are provided to validate the analytical results. 相似文献