Self-healing coatings inspired by biological systems possess the ability to repair physical damage or recover functional performance with minimal or no intervention. This article provides a ...comprehensive and updated review on the advantages and limitations associated with common autonomous and non-autonomous self-healing mechanisms in protective organic coatings used for anti-corrosion purposes. The autonomous healing mechanisms are often enabled by embedding polymerizable healing agents or corrosion inhibitors in the coating matrices. For non-autonomous mechanisms, the healing effects are induced by external heat or light stimuli, which trigger the chemical reactions or physical transitions necessary for bond formation or molecular chain movement.
Crowdsourced Data Management: A Survey Guoliang Li; Jiannan Wang; Yudian Zheng ...
IEEE transactions on knowledge and data engineering,
2016-Sept.-1, 2016-9-1, 20160901, Letnik:
28, Številka:
9
Journal Article
Recenzirano
Any important data management and analytics tasks cannot be completely addressed by automated processes. These tasks, such as entity resolution, sentiment analysis, and image recognition can be ...enhanced through the use of human cognitive ability. Crowdsouring platforms are an effective way to harness the capabilities of people (i.e., the crowd) to apply human computation for such tasks. Thus, crowdsourced data management has become an area of increasing interest in research and industry. We identify three important problems in crowdsourced data management. (1) Quality Control: Workers may return noisy or incorrect results so effective techniques are required to achieve high quality; (2) Cost Control: The crowd is not free, and cost control aims to reduce the monetary cost; (3) Latency Control: The human workers can be slow, particularly compared to automated computing time scales, so latency-control techniques are required. There has been significant work addressing these three factors for designing crowdsourced tasks, developing crowdsourced data manipulation operators, and optimizing plans consisting of multiple operators. In this paper, we survey and synthesize a wide spectrum of existing studies on crowdsourced data management. Based on this analysis we then outline key factors that need to be considered to improve crowdsourced data management.
We present a computing microsystem that uniquely leverages the bandwidth, density, and latency advantages of silicon photonic interconnect to enable highly compact supercomputer-scale systems. We ...describe and justify single-node and multinode systems interconnected with wavelength-routed optical links, quantify their benefits vis-a-vis electrically connected systems, analyze the constituent optical component and system requirements, and provide an overview of the critical technologies needed to fulfill this system vision. This vision calls for more than a hundredfold reduction in energy to communicate an optical bit of information. We explore the power dissipation of a photonic link, suggest a roadmap to lower the energy-per-bit of silicon photonic interconnects, and identify the challenges that will be faced by device and circuit designers towards this goal.
Adsorption isotherms and mechanism of phosphate by Fe–Cu binary oxide, which demonstrate high phosphate adsorption capacity and the possible adsorption process. Display omitted .
•The Fe–Cu binary ...oxide was effective for phosphate removal from water.•Phosphate was removed via replacing the surface sulfate and hydroxyl groups.•It could be effectively regenerated with dilute NaOH solution.
Phosphate is one of the main elements causing eutrophication and hence the development of high-efficiency and low-cost technologies for phosphate removal from water is of vital importance to alleviate the situation. In this study, nanostructured Fe–Cu binary oxides were synthesized via a facile coprecipitation process and its performance on phosphate removal was systematically evaluated. The as-prepared adsorbent with a Cu/Fe molar ratio of 1:2 was proved to possess the highest phosphate adsorption capacity. The adsorption isotherm data gave better fit to the Langmuir model, with a maximum phosphate adsorption capacity of 35.2mgg−1 at pH 7.0±0.1. Kinetic data correlated well with the pseudo-second-order kinetic model, indicating that the adsorption process might be chemical sorption. Thermodynamic data validated that the phosphate adsorption was an endothermic process. The solution pH has a big impact on the phosphate adsorption on the sorbent and acidic condition was favorable for the adsorption. The coexisting Cl−, SO42- and HCO3- anions had no significant influence on phosphate adsorption, while the present F− and SiO32- could suppress its adsorption, especially at high concentration level. The phosphate adsorption might be mainly achieved by the replacement of surface sulfate and hydroxyl groups by the phosphate species and formation of inner-sphere surface complexes at the water/oxide interface. Moreover, the spent Fe–Cu binary oxide could be effectively regenerated by NaOH solution for reuse. The high phosphate uptake capability and good reusability of the Fe–Cu binary oxide make it a potentially attractive adsorbent for the removal of phosphate from water.
Mycotoxins exposure from foodstuffs can trigger serious health hazards (e.g. cancers, deformity and mutation), which has been a global public health concern.
In recent years, large-scale poisoning ...incidents and international trade disputes caused by fungal contamination are extremely common. Unremitting efforts have been devoted to the investigations on classification, toxicity and occurrence of mycotoxins. Monitoring mycotoxins is highly important to ensure human health. Pretreatment technologies offer a pre-analytical separation process for reducing the instruments contamination, signal interference and matrix effects of complex foodstuffs.
In this review, the classification, toxicity and occurrence of mycotoxins were concisely summarized. We then concentrated our attentions on the methods of extraction, clean-up, separation and determination of mycotoxins. Especially, the rapid development of nanotechnology has brought many opportunities for sample pretreatment. We have also summarized the available and advanced adsorbents based on the emerging nanomaterials for pretreatment of mycotoxins in foodstuffs. At the end of the article, future opportunities and challenges in the field of mycotoxins research are tentatively proposed.
Key Findings and Conclusions: This review comprehensively summarized the latest achievements and improvements in the classification, toxicity, occurrence and detection approaches of mycotoxins. Impressively, the sample pretreatment and detection methods applied for mycotoxins determination in foodstuffs have been summarized, regarding the novel nanomaterial-based pretreatment technologies as well as the development of chromatographic and sensing technologies in the last six years. Furthermore, the current trends and the future perspectives in the toxicity and detection method of mycotoxins are tentatively proposed.
•Classification, toxicity and occurrence of mycotoxins were concisely summarized.•New methods of extraction, separation and determination of mycotoxins were reviewed.•Future opportunities and challenges of mycotoxins research are tentatively proposed.
As the Minamata Convention on Mercury comes into effect, controlling atmospheric mercury (Hg) emissions has become a compulsory goal. This study determined the mitigation options for the five ...Convention specified sources by considering their reduction potential of Hg emissions and the impact of future technology changes on emitted Hg forms and cross-media releases. Hg emissions will be reduced from 371 t in 2015 to 242 t in 2020 mainly by applying multipollutant control measures. Hg emissions will be reduced to 71 t in 2030 mainly with alternative measures and specific Hg removal measures (SMR). Alternative measures are effective for the studied sources except waste incineration (WI). SMR is preferentially recommended in cement clinker production due to the benefit of sectoral emissions and local deposition. Stringent requirements of Hg emission control will promote the use of SMR in WI. In case of nonferrous metal smelting (NFMS), only 8.7 t of Hg emissions will be reduced by SMR. However, the cobenefit of Hg reduction in sulfuric acid and local deposition will increase the relevance. On the contrary, applying SMR in coal-fired power plants (CFPPs) and coal-fired industrial boilers (CFIBs) requires comprehensive evaluation in terms of cost benefit and cross-media effect.
Supporting the translation from natural language (NL) query to visualization (NL2VIS) can simplify the creation of data visualizations because if successful, anyone can generate visualizations by ...their natural language from the tabular data. The state-of-the-art NL2VIS approaches ( e.g. , NL4DV and FlowSense) are based on semantic parsers and heuristic algorithms, which are not end-to-end and are not designed for supporting (possibly) complex data transformations. Deep neural network powered neural machine translation models have made great strides in many machine translation tasks, which suggests that they might be viable for NL2VIS as well. In this paper, we present ncNet , a Transformer-based sequence-to-sequence model for supporting NL2VIS, with several novel visualization-aware optimizations, including using attention-forcing to optimize the learning process, and visualization-aware rendering to produce better visualization results. To enhance the capability of machine to comprehend natural language queries, ncNet is also designed to take an optional chart template ( e.g. , a pie chart or a scatter plot) as an additional input, where the chart template will be served as a constraint to limit what could be visualized. We conducted both quantitative evaluation and user study, showing that ncNet achieves good accuracy in the nvBench benchmark and is easy-to-use.
Display omitted
•A general ion-inducing method was developed to obtain the unique electrocatalyst.•The doped C and the secondary metal help to modulate the electronic structure.•The hollow structure ...and 2D nanosheets collaborate to optimize the mass activity.•Extrinsic morphology and intrinsic electronic modulation synergistically boost OER.
Metal phosphide materials with unique nanostructures are of great interest for electrocatalysis. Herein, an ion-induction strategy is developed to synthesize a family of carbon incorporated homobimetallic (CoNi/C, CoCu/C, CoMn/C) phosphide electrocatalyst of hierarchical hollow polyhedral nanocages (HHPNCs) composed of ultrathin 2D subunits. The unique morphological structure effectively optimize the surface active sites, accelerate the charge transfer, and thus boost their superior catalytic activity. Density functional theory calculations reveal that not only the homogenously doped secondary metals but also the incorporated carbon effectively regulates the electronic structure and as a result collaboratively lower the kinetic energy barrier for the OER. Electrochemical measurements show high OER efficiency (η@10 mA cm−2 = 267, 262, and 283 mV for samples of CoNi/C-, CoMn/C-, and CoCu/C-HHPNC, respectively) and durability in alkaline electrolytes. Especially, the prepared carbon incorporated homobimetallic HHPNCs show very much higher (almost 9 times) mass activity than the particle counterpart.
A thiol-functionalized magnetic mesoporous silica material (called SH-mSi@Fe
3O
4), synthesized by a modified Stöber method, has been investigated as a convenient and effective adsorbent for heavy ...metal ions. Structural characterization by powder X-ray diffraction, N
2 adsorption–desorption isotherm, Fourier transform infrared spectroscopy and elemental analyses confirms the mesoporous structure and the organic moiety content of this adsorbent. The high saturation magnetization (38.4
emu/g) make it easier and faster to be separated from water under a moderate magnetic field. Adsorption kinetics was elucidated by pseudo-second-order kinetic equation and exhibited 3-stage intraparticle diffusion mode. Adsorption isotherms of Hg and Pb fitted well with Langmuir model, exhibiting high adsorption capacity of 260 and 91.5
mg of metal/g of adsorbent, respectively. The distribution coefficients of the tested metal ions between SH-mSi@Fe
3O
4 and different natural water sources (groundwater, lake water, tap water and river water) were above the level of 10
5
mL/g. The material was very stable in different water matrices, even in strong acid and alkaline solutions. Metal-loaded SH-mSi@Fe
3O
4 was able to regenerate in acid solution under ultrasonication. This novel SH-mSi@Fe
3O
4 is suitable for repeated use in heavy metal removal from different water matrices.
Privacy leakage is a serious issue in spatial crowdsourcing in various scenarios. In this paper, we study privacy protection in spatial crowdsourcing. The main challenge is to efficiently assign ...tasks to nearby workers without needing to know the exact locations of tasks and workers. To address this problem, we propose a privacy-preserving framework without online trusted third parties. We devise a grid-based location protection method, which can protect the locations of workers and tasks while keeping the distance-aware information on the protected locations such that we can quantify the distance between tasks and workers. We propose an efficient task assignment algorithm, which can instantly assign tasks to nearby workers on encrypted data. To protect the task content, we leverage both attribute-based encryption and symmetric-key encryption to establish secure channels through servers, which ensures that the task is delivered securely and accurately by any untrusted server. Moreover, we analyze the security properties of our method. We have conducted real experiments on real-world datasets. Experimental results show that our method outperforms existing approaches.