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排序方式: 共有274条查询结果,搜索用时 15 毫秒
1.
Achieving robot autonomy is a fundamental objective in Mobile Robotics. However in order to realize this goal, a robot must
be aware of its location within an environment. Therefore, the localization problem (i.e.,the problem of determining robot
pose relative to a map of its environment) must be addressed. This paper proposes a new biology-inspired approach to this
problem. It takes advantage of models of species reproduction to provide a suitable framework for maintaining the multi-hypothesis.
In addition, various strategies to track robot pose are proposed and investigated through statistical comparisons.
The Bacterial Colony Growth Algorithm (BCGA) provides two different levels of modeling: a background level that carries on the multi-hypothesis and a foreground level that identifies the best hypotheses according to an exchangeable strategy. Experiments, carried out on the robot ATRV-Jr
manufactured by iRobot, show the effectiveness of the proposed BCGA.
相似文献
Mattia ProsperiEmail: |
2.
Baeyens Y. Dorschky C. Weimann N. Qinghung Lee Kopf R. Georgiou G. Mattia J.P. Hamm R. Young-Kai Chen 《Microwave Theory and Techniques》2000,48(12):2403-2408
Compact monolithic integrated differential voltage-controlled oscillators (VCOs) operating in W-band were realized using InP-based heterojunction bipolar transistors (HBTs). The oscillators, with a total chip size of 0.6 by 0.35 mm2, are based on a balanced Colpitts-type topology with a coplanar transmission-line resonator. By varying the voltage across the base-collector junction of the HBT in the current mirror and by changing the current in the VCO, the oscillation frequency can be tuned between 84 and 106 GHz. At 100 GHz, a differential voltage swing of 400 mV is obtained, which should be sufficient to drive 100 Gb/s digital logic. By combining the balanced outputs of a similar differential VCO in a push-push configuration, a compact source with close to -10 dBm output power and a tuning range between 138 and 150 GHz is obtained 相似文献
3.
Mattia Boniardi Daniele IelminiInnocenzo Tortorelli Andrea RedaelliAgostino Pirovano Mario AllegraMichele Magistretti Camillo BresolinDavide Erbetta Alberto ModelliEnrico Varesi Fabio PellizzerAndrea L. Lacaita Roberto Bez 《Solid-state electronics》2011,58(1):11-16
The phase-change memory (PCM) technology is considered as one of the most attractive non-volatile memory concepts for next generation data storage. It relies on the ability of a chalcogenide material belonging to the Ge-Sb-Te compound system to reversibly change its phase between two stable states, namely the poly-crystalline low-resistive state and the amorphous high-resistive state, allowing the storage of the logical bit. A careful study of the phase-change material properties in terms of the set operation performance, the program window and the electrical switching parameters as a function of composition is very attractive in order to enlarge the possible PCM application spectrum. Concerning the set performance, a crystallization kinetics based interpretation of the observed behavior measured on different Ge-Sb-Te compounds is provided, allowing a physics-based comprehension of the reset-to-set transition. 相似文献
4.
Jhon?Alexander?Gomez CaicedoEmail author Oscar?E.?Mattia Hamilton?Klimach Sergio?Bampi 《Analog Integrated Circuits and Signal Processing》2016,88(2):333-345
This work presents a resistorless self-biased and small area sub-bandgap voltage reference that works in the nano-ampere consumption range with 0.75 V of power supply. The circuit applies a curvature compensation technique that allows an extended temperature range without compromising the temperature stability. The behavior of the circuit is analytically described, and a design methodology is proposed which allows the separate adjustment of the bipolar junction transistor bias current and its curvature compensation. Simulation results are presented for a 180 nm CMOS process, where a reference voltage of 469 mV is designed, with a temperature coefficient of 5 ppm/°C for the ?40 to 125 °C extended temperature range. The power consumption of the whole circuit is 16.3 nW under a 0.75 V power supply at 27 °C. The estimated silicon area is 0.0053 mm2. 相似文献
5.
Marco Baldi Franco Chiaraluce Nicola Maturo Giacomo Ricciutelli Alessandro Ardito Francesco Barbaglio Stefano Finocchiaro Lorenzo Simone Ricard Abell Javier De Vicente Mattia Mercolino 《International Journal of Satellite Communications and Networking》2019,37(6):571-587
A thorough analysis of the behavior of error‐correcting codes over space links affected by solar scintillation is presented. The relevant channel parameters are fixed through the development of a model based on real missions' data. Both telecommand and telemetry links are considered in fast and slow fading conditions. Besides classical coherent modulation schemes, the possibility to use noncoherent modulation schemes is considered, to eliminate the problem of phase tracking. For the case of channels with very slow fading, the use of external interleavers or erasure coding is proposed to cope with error bursts. 相似文献
6.
Righi V Di Nunzio M Danesi F Schenetti L Mucci A Boschetti E Biagi P Bonora S Tugnoli V Bordoni A 《Lipids》2011,46(7):627-636
It is well recognized that a high dietary intake of long-chain polyunsaturated fatty acids (LC-PUFA) has profound benefits
on health and prevention of chronic diseases. In particular, in recent years there has been a dramatic surge of interest in
the health effects of n-3 LC-PUFA derived from fish, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. Notwithstanding,
the metabolic fate and the effects of these fatty acids once inside the cell has seldom been comprehensively investigated.
Using cultured neonatal rat cardiomyocytes as model system we have investigated for the first time, by means of high-resolution
magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy in combination with gas chromatography (GC), the
modification occurring in the cell lipid environment after EPA and DHA supplementation. The most important difference between
control and n-3 LC-PUFA-supplemented cardiomyocytes highlighted by HR-MAS NMR spectroscopy is the increase of signals from
mobile lipids, identified as triacylglycerols (TAG). The observed increase of mobile TAG is a metabolic response to n-3 LC-PUFA
supplementation, which leads to an increased lipid storage. The sequestration of mobile lipids in lipid bodies provides a
deposit of stored energy that can be accessed in a regulated fashion according to metabolic need. Interestingly, while n-3
LC-PUFA supplementation to neonatal rat cardiomyocytes causes a huge variation in the cell lipid environment, it does not
induce detectable modifications in water-soluble metabolites, suggesting negligible interference with normal metabolic processes. 相似文献
7.
8.
Russo Krauss I Sica F Mattia CA Merlino A 《International journal of molecular sciences》2012,13(3):3782-3800
Serum albumin is one of the most widely studied proteins. It is the most abundant protein in plasma with a typical concentration of 5 g/100 mL and the principal transporter of fatty acids in plasma. While the crystal structures of human serum albumin (HSA) free and in complex with fatty acids, hemin, and local anesthetics have been characterized, no crystallographic models are available on bovine serum albumin (BSA), presumably because of the poor diffraction power of existing hexagonal BSA crystals. Here, the crystallization and diffraction data of a new BSA crystal form, obtained by the hanging drop method using MPEG 5K as precipitating agent, are presented. The crystals belong to space group C2, with unit-cell parameters a = 216.45 Å, b = 44.72 Å, c = 140.18 Å, β = 114.5°. Dehydration was found to increase the diffraction limit of BSA crystals from ~8 Å to 3.2 Å, probably by improving the packing of protein molecules in the crystal lattice. These results, together with a survey of more than 60 successful cases of protein crystal dehydration, confirm that it can be a useful procedure to be used in initial screening as a method of improving the diffraction limits of existing crystals. 相似文献
9.
Arianna Giacomini Sara Taranto Sara Rezzola Sara Matarazzo Elisabetta Grillo Mattia Bugatti Alessia Scotuzzi Jessica Guerra Martina Di Trani Marco Presta Roberto Ronca 《International journal of molecular sciences》2020,21(24)
Lung cancer represents an extremely diffused neoplastic disorder with different histological/molecular features. Among the different lung tumors, non-small-cell lung cancer (NSCLC) is the most represented histotype, characterized by various molecular markers, including the expression/overexpression of the fibroblast growth factor receptor-1 (FGFR1). Thus, FGF/FGFR blockade by tyrosine kinase inhibitors (TKi) or FGF-ligand inhibitors may represent a promising therapeutic approach in lung cancers. In this study we demonstrate the potential therapeutic benefit of targeting the FGF/FGFR system in FGF-dependent lung tumor cells using FGF trapping (NSC12) or TKi (erdafitinib) approaches. The results show that inhibition of FGF/FGFR by NSC12 or erdafitinib induces apoptosis in FGF-dependent human squamous cell carcinoma NCI-H1581 and NCI-H520 cells. Induction of oxidative stress is the main mechanism responsible for the therapeutic/pro-apoptotic effect exerted by both NSC12 and erdafitinib, with apoptosis being abolished by antioxidant treatments. Finally, reduction of c-Myc protein levels appears to strictly determine the onset of oxidative stress and the therapeutic response to FGF/FGFR inhibition, indicating c-Myc as a key downstream effector of FGF/FGFR signaling in FGF-dependent lung cancers. 相似文献
10.
Arianna Zanoni Cora Casiraghi Riccardo Po Paolo Biagini Mattia Sponchioni Davide Moscatelli 《大分子材料与工程》2023,308(1):2200443
Redispersible polymer powders (RDPPs), i.e., additives obtained from core–shell nanoparticles and commercialized in the form of a dry powder, find intensive application in the concrete industry. However, they are mainly produced from fossil resources. Therefore, the development of bio-based RDPPs is important to reduce the carbon footprint of these additives. In this work, two types of core–shell nanoparticles with a high percentage of bio-based content are synthesized and show to be good candidates as RDPPs. In the first case, up to 75% of bio-based content is obtained by combining lauryl acrylate, derived from coconut and palm kernel oil, as main core material, with isobornyl methacrylate, coming from pine resin, exploited to create the outer harder shell. In the second case, a degradable macromonomer obtained by the ring opening polymerization of lactide using 2-hydroxyethyl methacrylate as initiator is used as the core-forming monomer to obtain degradable RDPPs. In both cases, the particles are synthesized with a two-step emulsion polymerization process conducted in one pot and then spray-dried to obtain the RDPPs of interest. The morphology and redispersibility of the powders are characterized. Finally, their use as concrete additives is preliminarily assessed by evaluating their effect on changes in the surface morphologies of concrete specimens. 相似文献