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101.
In this paper, we study the dynamic survivable routing problem, both in optical networks without wavelength conversion and in optical networks with sparse wavelength conversion, and propose a novel hybrid algorithm for it based on the combination of mobile agents technique and genetic algorithms (GA). By keeping a suitable number of mobile agents in the network to cooperatively explore the network states and continuously report cycles (that are formed by two disjoint-link routes) into the routing tables, our new hybrid algorithm can promptly determine the first population of cycles for a new request based on the routing table of its source node, without the time consuming process associated with current GA-based lightpath protection schemes. We further improve the performance of our algorithm by introducing a more advanced fitness function that is suitable for both the above networks. Extensive simulation studies on the ns-2 network simulator show that our hybrid algorithm achieves a significantly lower blocking probability than the conventional survivable routing algorithms for all the cases we studied.  相似文献   
102.
Clustering is a crucial method for deciphering data structure and producing new information. Due to its significance in revealing fundamental connections between the human brain and events, it is essential to utilize clustering for cognitive research. Dealing with noisy data caused by inaccurate synthesis from several sources or misleading data production processes is one of the most intriguing clustering difficulties. Noisy data can lead to incorrect object recognition and inference. This research aims to innovate a novel clustering approach, named Picture-Neutrosophic Trusted Safe Semi-Supervised Fuzzy Clustering (PNTS3FCM), to solve the clustering problem with noisy data using neutral and refusal degrees in the definition of Picture Fuzzy Set (PFS) and Neutrosophic Set (NS). Our contribution is to propose a new optimization model with four essential components: clustering, outlier removal, safe semi-supervised fuzzy clustering and partitioning with labeled and unlabeled data. The effectiveness and flexibility of the proposed technique are estimated and compared with the state-of-art methods, standard Picture fuzzy clustering (FC-PFS) and Confidence-weighted safe semi-supervised clustering (CS3FCM) on benchmark UCI datasets. The experimental results show that our method is better at least 10/15 datasets than the compared methods in terms of clustering quality and computational time.  相似文献   
103.
为保证核电主泵满足反应堆停堆和断电事故后惰转时间的要求,对屏蔽式主泵机组的转动惯量要求、飞轮配重方案以及主泵转子轴系的动态性能进行分析,给出了飞轮方案,并进行轴承水膜刚度对转子轴系动态性能影响的敏感性分析.  相似文献   
104.
The comparison of resistive switching (RS) storage in the same device architecture is explored for atomic layer deposition (ALD) Al2O3, HfO2 and HfAlOx‐based resistive random access memory (ReRAM) devices. Among them, the deeper high‐ and low‐ resistance states, more uniform VSETVRES, persistent ROFF/RON (>102) ratio and endurance up to 105 cycles during both DC and AC measurements were observed for HfAlOx‐based device. This improved behavior is attributed to the intermixing of amorphous Al2O3/HfO2 oxide layers to form amorphous thermally stable HfAlOx thin films by consecutive‐cycled ALD. In addition, the higher oxygen content at Ti/HfAlOx thin films interface was found within the energy dispersive spectroscopy analysis (EDS). We believe this higher oxygen content at the interface could lead to its sufficient storage and supply, leading to the stable filament reduction‐oxidation operation. Further given insight to the RS mechanism, SET/RESET power necessities and scavenging effect shed a light to the enhancement of HfAlOx‐based ReRAM device as well.  相似文献   
105.
LSGM is known to have very serious interfacial reactivity with other unit cell components even though it is one of the most favorable solid electrolytes for intermediate-temperature SOFCs. Above all, the formation of a La-deficient La-Sr-Ga-O phase at the LSGM/NiO or the LSGM/CeO2 interface is most problematic in LSGM-based SOFCs due to the very resistive nature of its electrical property in fuel cell operating conditions. In this study, we investigated the interfacial reactions in LSGM-based SOFCs under various fabrication conditions, in order to discern a method to either avoid or diminish the undesirable influence of these interfacial reactions. Microstructural evolution due to the chemical reactions between the anode and electrolyte layer were characterized with an Environmental Scanning Electron Microscopy (ESEM-PHILIPS XL-30) and an Energy Dispersive X-ray (EDX-Link XL30) analysis. The spatial distributions of each constituent element at the interfaces were thoroughly investigated with an Electron Probe Micro-Analyzer (EPMA-JEOL. JXA-8600).  相似文献   
106.
Lam  Kam-Yiu  Hung  Sheung-Lun  Son  Sang H. 《Real-Time Systems》1997,13(2):141-166
The use of Static Two Phase Locking Protocols (S2PL) for concurrency control in real-time database systems (RTDBS) has received little attention in the past. Actually, real-time S2PL (RT-S2PL) protocols do possess some desirable features making them suitable for RTDBS, especially for distributed real-time database systems (DRTDBS) in which remote locking is required and distributed deadlock is possible. In this paper, different RT-S2PL protocols are proposed. They differ in their methods of reducing the blocking time of higher priority transactions. Their performance is studied and compared with a real-time dynamic two phase locking protocol (RT-D2PL), called Hybrid Two Phase Locking (Hb2PL). The impact of different system and workload parameters, such as mean inter-arrival time of transactions, number of remote lock requests of a transaction, communication overhead for sending messages, and database size on their performance have been examined. The performance results indicate that the RT-S2PL protocols are suitable for DRTDBS in which the proportion of local locks of a transaction is small and the communication overhead for locking is high.  相似文献   
107.
This paper presents a new design and analysis of a haptic interface for a gastrointestinal endoscopy simulation. The gastrointestinal endoscopy is a procedure in which the digestive tract and organs of a patient are diagnosed and treated using a long and flexible endoscope. The developed haptic interface incorporates two degrees of freedom (DOF), each of which is necessary to describe the movements of an endoscope during the actual endoscopy procedures. The haptic interface has a translational motion mechanism to implement the insertion movement of the endoscope, and a rotational motion mechanism to implement the rotational movement of the endoscope. The endoscope included in the haptic interface is supported by a folding guide to prevent the endoscope from buckling. Force feedback in each direction is provided by wire-driven mechanisms. The developed haptic interface has a workspace, sensitivity, and maximum attainable force and torque enough to simulate the endoscopy procedures such as colonoscopy, upper GI (gastrointestinal) endoscopy, and endoscopic retrograde cholangiopancreatography (ERCP). The developed haptic interface is applied to implementation of a colonoscopy simulation. Performance including force bandwidth is evaluated through experiments and simulation.  相似文献   
108.
Unlike fossil-fueled generation, solar energy resources are geographically distributed and highly intermittent, which makes their direct control extremely difficult and requires storage units as an additional concern. The goal of this research is to design and develop a flexible tool, which will allow us to obtain (1) an optimal capacity of an integrated photovoltaic (PV) system and storage units and (2) an optimal operational decision policy considering the current and future market prices of the electricity. The proposed tool is based on hybrid (system dynamics model and agent-based model) simulation and meta-heuristic optimization. In particular, this tool has been developed for three different scenarios (involving different geographical scales), where PV-based solar generators, storage units (compressed-air-energy-storage (CAES) and super-capacitors), and grid are used in an integrated manner to supply energy demands. Required data has been gathered from various sources, including NASA and TEP (utility company), US Energy Information Administration, National Renewable Energy Laboratory, commercial PV panel manufacturers, and publicly available reports. The constructed tool has been demonstrated to (1) test impacts of several factors (e.g. demand growth, efficiencies in PV panel and CAES system) on the total cost of the integrated generation and storage system and an optimal mixture of PV generation and storage capacity, and to (2) demonstrate an optimal operational policy.  相似文献   
109.
The feasibility of employing a NiO-yttria stabilized zirconia (YSZ) nano-powder slurry spin coating (NSC) to fabricate a thin film (≤ 1 μm) electrolyte solid oxide fuel cell (TF-SOFC) on a relatively rough surface of the support is investigated in this study. The NiO-YSZ nano-powder with ~ 200 nm particle size was synthesized by a single-step glycine nitrate process and super-apex milling. Through varying the NiO-YSZ nano-powder slurry condition by changing polymeric additives, a leveled surface of the spin coated layer which enabled to overcome the surface roughness of the bulk ceramic processed anode substrate was obtained. On the NSC layer, TF-SOFC components with flat profiles could be fabricated using pulsed laser deposition. A stable open circuit voltage of 1.04 V was obtained with these thin film components on an anode support with a rough surface.  相似文献   
110.
Dense granule proteins (GRAs) are essential components in Toxoplasma gondii, which are suggested to be promising serodiagnostic markers in toxoplasmosis. In this study, we investigated the function of GRA9 in host response and the associated regulatory mechanism, which were unknown. We found that GRA9 interacts with NLR family pyrin domain containing 3 (NLRP3) involved in inflammation by forming the NLRP3 inflammasome. The C-terminal of GRA9 (GRA9C) is essential for GRA9–NLRP3 interaction by disrupting the NLRP3 inflammasome through blocking the binding of apoptotic speck-containing (ASC)-NLRP3. Notably, Q200 of GRA9C is essential for the interaction of NLRP3 and blocking the conjugation of ASC. Recombinant GRA9C (rGRA9C) showed an anti-inflammatory effect and the elimination of bacteria by converting M1 to M2 macrophages. In vivo, rGRA9C increased the anti-inflammatory and bactericidal effects and subsequent anti-septic activity in CLP- and E. coli- or P. aeruginosa-induced sepsis model mice by increasing M2 polarization. Taken together, our findings defined a role of T. gondii GRA9 associated with NLRP3 in host macrophages, suggesting its potential as a new candidate therapeutic agent for sepsis.  相似文献   
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