Advanced Materials Research Vol. 679

Abstract: This paper studied the influence of neutron irradiation on the characteristics of 980nm pumped erbium-doped fiber amplifier(EDFA). After 7 days neutron irradiation, with the total fluence of 1.5×1013n/cm2, radiation induced loss changed little compared with pre-irradiation, maximum difference of single signal and WDM signal between pre-irradiation and post- irradiation are 0.5dB and 0.6dB, respectively. EDFA affected by neutron irradiation got less loss when the input signal power is higher.

Abstract: We prepared Y3Al5O12:xCe3+ (0.002≤x≤0.010) phosphors by the solution combustion method, using citric acid as the combustion fuel. The crystal structure, surface morphology, and photoluminescence properties were studied, depending on Ce3+ content. The Y3Al5O12:xCe3+ powders prepared showed high-quality characteristics, i.e., smooth surface as well as regular and spherical-like morphology. The excitation and emission intensities of the Y3Al5O12:xCe3+ phosphors increased with Ce3+ content up to x=0.010. The broad emission bands peaked at 525 nm were caused by the 5d–4f transition of the Ce3+ activator. The solution combustion method could be highly favorable for preparing high-quality yellow Y3Al5O12:xCe3+ phosphors.

Abstract: In recent years, lanthanide-ion doped nanocrystals have attracted considerable attention for its promising applications in multiplexed biological labeling. These materials can convert near-infrared (NIR) light into visible and offer low autofluorescence, high resistance to photobleaching, high penetration depth and large anti-Stokes shifts. With the development of these techniques, the ability to manipulate multicolor output has become more important for its biological and photovoltaic applications. This review mainly focuses on the recent development of various approaches for the multicolor tuning of lanthanide-ion doped upconversion nanoparticles.

Abstract: Real-time task schedule problem in Chip-Multiprocessor (CMP) receives wide attention in recent years. It is partly because the increasing demand for CMP solutions call for better schedule algorithm to exploit the full potential of hardware, and partly because of the complexity of schedule problem, which itself is an NP-hard problem. To address this task schedule problem, various of heuristics have been studied, among which, Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and Simulated Annealing (SA) are the most popular ones. In this paper, we implement these 3 schedule heuristics, and compare their performance under the context of real-time tasks scheduling on CMP. According to the results of our intensive simulations, PSO has the best fitness optimization of these 3 algorithms, and SA is the most efficient algorithm.

Abstract: To prompt the present situation and utilized values of fundamental geo-information, this paper focuses on a change detection method based on remote sensing image and GIS vector for linear features. Firstly unilateral vector was taken as original value of linear features; then edge points were picked up by pyramid decomposition and multi-scale template matching, and Ziplock Snake method was adopted to further improve the extraction results; finally buffer zone was constructed to distinguish the changed part. This change detection method proves to have higher degree of automation and more precise, so long as the registration of remote sensing image and vector map is accurate.

Abstract: In fact, the 1/f noise spectrum is correlated with the interface trap density of a MOSFET gate oxide, and the trap density generation in gate oxide is strong dependently on the hot-carrier injection. In this paper, we will investigate this phenomenon and compare with the threshold voltage shifted measured by the static I-V analysis. Eventually, it is found that the technique of the low frequency 1/f noise spectrum is an accurate and sensitive tool to detect the hot-carrier damage.

Abstract: We study various kinds of entanglement purification schemes for quantum repeater distributed maximally entangled pairs over long distances. We then investigate two protocols in detail, and present that they have the same essence in principle but operated by different means. In order to compare the two different protocols, we introduce a parameter represented the admixture degree of system to show the optimal protocol that is obtainable. Finally, we present that the efficiency of purification protocol relate to the fidelity of the initial states of the system. For the initial state of the system with high fidelity entanglement, we can obtain the required particles after a few iterations.

Abstract: Failure mode effects and criticality analysis (FMECA) is a widely useful design tool for enhancing product quality, safety and reliability. Most of the current FMECA procedure is in accordance with MIL-STD-1629A by which to conduct FMECA and criticality analysis, which is able to prioritize the failure modes and undertake limited corrective actions toward eliminating product risks. However, the criticality analysis calculation and its interpretation for a failure mode have some mathematical difficulties and erroneous omissions. To resolve these problems, this study proposes a new amalgamated criticality analysis methodology, which is knowledge-based to obtain the four different factor criteria and then using the maximal entropy ordered weighted geometric averaging (ME-OWGA) approach to compute the criticality numbers for a system. This study evaluates criticality analysis in the context of a communication system; the experimental results demonstrate that the proposed method is both accurate and provides discriminating analysis information that helps decision making in product design processes.

Abstract: The importance of UWB radar system for indoor applications is of keen interest. Applications such as across the wall monitoring, through wall detection, intrusion detection and under rubble vital sign detection are of cumulative interest and are also used in modern rescue systems to help the trapped human beings, along with detection and activity monitoring across the wall. In this paper we have studied across the wall detection of presence of different objects by applying the fractional Fourier transform. Computer aided design based simulations for indoor environment are accomplished by using finite difference time domain solution for Maxwell’s equations. Finally, fractal analysis is realized for the collected signals reflected from the objects present across the wall.

Abstract: In this paper, we propose a localization scheme considering the reliability of RSSI (Received Signal Strength Indication) measurements in the WSN (Wireless Sensor Network) environment. This scheme attempts to reduce location errors due to indoor obstacles or environmental factors, when location calculations are based on RSSI. The standard deviation is used to evaluate the reliability of RSSI measurements from the reference node. Also, the directional path loss exponent is calculated through learning with respect to the reference node. The experimental results show that the proposed localization scheme improves the performance significantly in terms of location accuracy, compared to the existing RSSI-based approaches.