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1.
Yoram Bachrach Ariel Parnes Ariel D. Procaccia Jeffrey S. Rosenschein 《Autonomous Agents and Multi-Agent Systems》2009,19(2):153-172
Decentralized Reputation Systems have recently emerged as a prominent method of establishing trust among self-interested agents
in online environments. A key issue is the efficient aggregation of data in the system; several approaches have been proposed,
but they are plagued by major shortcomings. We put forward a novel, decentralized data management scheme grounded in gossip-based
algorithms. Rumor mongering is known to possess algorithmic advantages, and indeed, our framework inherits many of their salient
features: scalability, robustness, a global perspective, and simplicity. We demonstrate that our scheme motivates agents to
maintain a very high reputation, by showing that the higher an agent’s reputation is above the threshold set by its peers,
the more transactions it would be able to complete within a certain time unit. We analyze the relation between the amount
by which an agent’s average reputation exceeds the threshold and the time required to close a deal. This analysis is carried
out both theoretically, and empirically through a simulation system called GossipTrustSim. Finally, we show that our approach is inherently impervious to certain kinds of attacks.
A preliminary version of this article appeared in the proceedings of IJCAI 2007. 相似文献
2.
Shengyan Yin Yulia Goldovsky Moshe Herzberg Lei Liu Hang Sun Yanyan Zhang Fanben Meng Xuebo Cao Darren D. Sun Hongyu Chen Ariel Kushmaro Xiaodong Chen 《Advanced functional materials》2013,23(23):2972-2978
Fabricating free‐standing, three‐dimensional (3D) ordered porous graphene structure can service a wide range of functional materials such as environmentally friendly materials for antibacterial medical applications and efficient solar harvesting devices. A scalable solution processable strategy is developed to create such free‐standing hierarchical porous structures composed of functionalized graphene sheets via an “on water spreading” method. The free‐standing film shows a large area uniform honeycomb structure and can be transferred onto any substrate of interest. The graphene‐based free‐standing honeycomb films exhibit superior broad spectrum antibacterial activity as confirmed using green fluorescent protein labeled Pseudomonas aeruginosa PAO1 and Escherichia coli as model pathogens. Functional nanoparticles such as titanium dioxide (TiO2) nanoparticles can be easily introduced into conductive graphene‐based scaffolds by premixing. The formed composite honeycomb film electrode shows a fast, stable, and completely reversible photocurrent response accompanying each switch‐on and switch‐off event. The graphene‐based honeycomb scaffold enhances the light‐harvesting efficiency and improves the photoelectric conversion behavior; the photocurrent of the composite film is about two times as high as that of the pure TiO2 film electrode. Such composite porous films combining remarkably good electrochemical performance of graphene, a large electrode/electrolyte contact area, and excellent stability during the photo‐conversion process hold promise for further applications in water treatment and solar energy conversion. 相似文献
3.
Peng Li Haibin Jiang Ariel Barr Zhichu Ren Rui Gao Hua Wang Weiwei Fan Meifang Zhu Guiyin Xu Ju Li 《Advanced functional materials》2021,31(51):2105845
Mercury, lead, and cadmium are among the most toxic and carcinogenic heavy metal ions (HMIs), posing serious threats to the sustainability of aquatic ecosystems and public health. There is an urgent need to remove these ions from water by a cheap but green process. Traditional methods have insufficient removal efficiency and reusability. Structurally robust, large surface-area adsorbents functionalized with high-selectivity affinity to HMIs are attractive filter materials. Here, an adsorbent prepared by vulcanization of polyacrylonitrile (PAN), a nitrogen-rich polymer, is reported, giving rise to PAN-S nanoparticles with cyclic π-conjugated backbone and electronic conductivity. PAN-S can be coated on ultra-robust melamine (ML) foam by simple dipping and drying. In agreement with hard/soft acid/base theory, N- and S-containing soft Lewis bases have strong binding to Hg2+, Pb2+, Cu2+, and Cd2+, with extraordinary capture efficiency and performance stability. Furthermore, the used filters, when collected and electrochemically biased in a recycling bath, can release the HMIs into the bath and electrodeposit on the counter-electrode as metallic Hg0, Pb0, Cu0, and Cd0, and the PAN-S@ML filter can then be reused at least 6 times as new. The electronically conductive PAN-S@ML filter can be fabricated cheaply and holds promise for scale-up applications. 相似文献
4.
Frejus Ariel Kpedetin Sodedji Dahye Ryu Jaeyoung Choi Symphorien Agbahoungba Achille Ephrem Assogbadjo Simon-Pierre Assanvo NGuetta Je Hyeong Jung Chu Won Nho Ho-Youn Kim 《International journal of molecular sciences》2022,23(7)
The development and promotion of biofortified foods plants are a sustainable strategy for supplying essential micronutrients for human health and nutrition. We set out to identify quantitative trait loci (QTL) associated with carotenoid content in cowpea sprouts. The contents of carotenoids, including lutein, zeaxanthin, and β-carotene in sprouts of 125 accessions were quantified via high-performance liquid chromatography. Significant variation existed in the profiles of the different carotenoids. Lutein was the most abundant (58 ± 12.8 mg/100 g), followed by zeaxanthin (14.7 ± 3.1 mg/100 g) and β-carotene (13.2 ± 2.9 mg/100 g). A strong positive correlation was observed among the carotenoid compounds (r ≥ 0.87), indicating they can be improved concurrently. The accessions were distributed into three groups, following their carotenoid profiles, with accession C044 having the highest sprout carotenoid content in a single cluster. A total of 3120 genome-wide SNPs were tested for association analysis, which revealed that carotenoid biosynthesis in cowpea sprouts is a polygenic trait controlled by genes with additive and dominance effects. Seven loci were significantly associated with the variation in carotenoid content. The evidence of variation in carotenoid content and genomic regions controlling the trait creates an avenue for breeding cowpea varieties with enhanced sprouts carotenoid content. 相似文献
5.
Lui Ng Sunny Kit-Man Wong Zheng Huang Colin Siu-Chi Lam Ariel Ka-Man Chow Dominic Chi-Chung Foo Oswens Siu-Hung Lo Roberta Wen-Chi Pang Wai-Lun Law 《International journal of molecular sciences》2022,23(3)
CD26 has been reported as a marker for colorectal cancer stem cells endowed with tumor-initiating properties and capable of colorectal cancer (CRC) metastasis. In this study, we investigated the functional effect of CD26 on CRC angiogenesis and metastasis, and the potential underlying mechanism. The functional effects of CD26 overexpression or repression were determined by a wound healing experiment, and cell migration and invasion assays in vitro and in mouse models. Differentially expressed genes regulated by CD26 were identified by genome-wide mRNA expression array and validated by quantitative PCR. CD26 functionally regulated CRC cell migration and invasion in vitro and angiogenesis and metastasis in vivo. Genome-wide mRNA expression array and qPCR showed that MMP1 was up-regulated in CD26+ subpopulation, and a subsequent experiment demonstrated the regulatory effect of CD26 on MMP1 in CRC cell lines with CD26 repression or overexpression. Furthermore, overexpression of CAV1 abrogated the CD26-regulated MMP1 induction in CRC cell lines. This study demonstrated the functional roles of CD26 in inducing CRC migration, invasion, angiogenesis and metastasis and identified the potential involvement of MMP1 and CAV1 in such process. CD26 is an attractive therapeutic target for combating tumor progression to improve the prognosis of CRC patients. 相似文献
6.
Ariel A. Boucheikhchoukh Christopher L. E. Swartz Eric Bouveresse Pierre Lutran Anna Robert 《American Institute of Chemical Engineers》2022,68(9):e17799
Uncertainty in refinery planning presents a significant challenge in determining the day-to-day operations of an oil refinery. Deterministic modeling techniques often fail to account for this uncertainty, potentially resulting in reduced profit. The stochastic programming framework explicitly incorporates parameter uncertainty in the problem formulation, thus giving preference to robust solutions. In this work, a nonlinear, multiperiod, industrial refinery problem is extended to a two-stage stochastic problem, formulated as a mixed-integer nonlinear program. A crude-oil sequencing case study is developed with binary scheduling decisions in both stages of the stochastic programming problem. Solution via a decomposition strategy based on the generalized Benders decomposition (GBD) algorithm is proposed. The binary decisions are designated as complicating variables that, when fixed, reduce the full-space problem to a series of independent scenario subproblems. Through the application of the GBD algorithm, a feasible mixed-integer solution is obtained that is more robust to uncertainty than its deterministic counterpart. 相似文献
7.
8.
Selective hydrogenation of cinnamaldehyde using Pd catalysts supported on Mg/Al mixed oxides: Influence of the Pd incorporation method 下载免费PDF全文
María J. Martínez‐Ortiz Miguel A. de la Rosa‐Guzmán Jorge R. Vargas‐García Jorge L. Flores‐Moreno Nancy Castillo Ariel Guzmán‐Vargas Sara Morandi Rosa M. Pérez‐Gutiérrez 《加拿大化工杂志》2018,96(1):297-306
A series of hydrotalcite‐like compounds was synthesized by varying Mg/Al molar ratio with values of 2, 3, and 4. After thermal treatment at 823 K, the corresponding mixed oxides were obtained and used as catalytic supports. The incorporation of a Pd metallic phase (0.5 g/g loading), was carried out by two methods: 1) in situ vapour phase thermal decomposition, and 2) impregnation by organic method. Fresh and calcined samples were characterized by XRD and N2 sorption experiments. The basic and metal functions were analyzed by CO2‐TPD and H2‐TPR. The Pd‐support interaction was studied by FTIR spectroscopy using CO as a probe molecule while the morphology of Pd nanoparticles on the catalysts was studied by SEM, HRTEM, and theoretical simulation using the Fast Fourier Transform (FFT) method. Finally, the catalytic activity results showed a higher conversion towards hydrocinnamaldehyde in the cinnamaldehyde hydrogenation reaction for the catalysts prepared by vapour phase thermal decomposition, compared with those prepared by organic method, showing the significant dependence on the catalytic activity and the Pd incorporation method. 相似文献
9.
Ariel Burgos Hernán Svoboda Zhuyao Zhang Estela Surian 《Journal of Materials Engineering and Performance》2018,27(12):6328-6338
Creep-resistant 9Cr steels are extremely important in thermal power generation industry due to their marked resistance to creep and corrosion. The weldability of these alloys is critical since they are used in welded construction equipment. The required mechanical properties are achieved after post-weld heat treatment. This study examined the effect of different post-weld heat treatments on microstructure and mechanical properties of creep strength-enhanced 9Cr steel welding deposits. It was obtained with an experimental flux-cored arc welding wire used under protective gas (Ar-20% CO2). The heat treatments used were: (1) tempering (760 °C?×?2 h), (2) solubilizing (1050 °C?×?1 h)?+?tempering (760 °C?×?2 h) and (3) solubilizing (1150 °C?×?1 h)?+?first tempering (660 °C?×?3 h)?+?second tempering (660 °C?×?3 h). All-weld metal chemical composition was analyzed, and hot tensile tests were carried out at different temperatures. Charpy-V impact tests and Vickers microhardness measurements were also performed. Microstructures were studied using x-ray diffraction and optical and scanning electron microscopy. In all cases, a martensitic matrix with intergranular and intra-granular precipitates was detected. In the as-welded condition, δ-ferrite was also found. Microhardness dropped, and the impact energy increased with post-weld heat treatments. The highest hot tensile strength result was achieved with samples submitted to austenization at 1150 °C and double tempering at 660 °C. 相似文献
10.
Gamboa Delgado EM López Barbosa N Prada Gómez GE Franco Cadena JT Landínez Navarro A 《Archivos latinoamericanos de nutrición》2010,60(3):247-253
The objective of this study was to determine associated factors to the consumption of fruit and vegetables (FV) in the adult population of each socioeconomic status (SES) in Bucaramanga, Colombia. We conducted a cross-sectional in a sample of 317 people and we measured socio-demographic, economic and anthropometric variables and dietary factors related to the purchase and consumption of FV. We made a survey, a 24-Hour dietary recall and we did anthropometric measurements. Portion sizes were estimated with a standardized set of utensils and food-photography atlas. Frequencies, measures of central tendency and dispersion were established and Logistic Regression models were used for the bi and multivariate analysis. Average consumption of FV was 162.6 g/day (188.5 g in high SES and 145.7 g in low SES, p = 0.056). On average 2 servings per day of FV (2.3 servings in high SES and 1.5 in low SES, p = 0.055). The prevalence of adequate intake of FV (more than 5 servings / day) was 8.6% (8.9% in high SES and 8.4% in low SES, p = 0.896). The associated factor to consumption of FV was BMI > or =25 (OR: 0.31, CI (95%): 0.11-0.89, p = 0.030), adjusted for occupation, income, SES, and number of family members. FV consumption is low; excess weight is the only variable associated to no-consumption of five or more servings; causes: cost to the consumption of fruit and flavor in the case of vegetables. 相似文献