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A sesbania gum‐g‐poly (acrylic acid‐co‐vinyl acetate) (SG‐g‐P (AA‐co‐VAc)) emulsion was prepared by free radical polymerization using environmental‐friendly sesbania gum (SG) as raw material and grafted with acrylic acid and vinyl acetate. It was applied to study the performance of preventing water leakage from the soil. The effects of acrylic acid/vinyl acetate (AA/VAc) monomer ratio, neutralization degree of AA, content of ammonium persulfate and polymerization temperature on the properties of emulsion were investigated. Characterization of the emulsion by FTIR, SEM, TGA, and particle size distribution showed that AA and VAc were successfully grafted onto SG. SG‐g‐P (AA‐co‐VAc) had good stability under the optimum synthesis condition. Compared to SG, the thermal stability of the product was improved. The consolidation layer was formed after the product was added to the soil, which might reduce the voids between soil particles and reduce the water penetration rate. This greatly expanded its application in the research of anti‐leakage performance. [ABSTRACT FROM AUTHOR]

It was an urgent problem in product development to quickly and accurately obtain customer need informations from customer behavior data by means of data-driven method. Therefore, the customer need model was studied, and the customer need modeling method driven by review data was proposed. Firstly, aiming at the problem that the number of topics was not easy to determine in the review analysis based on topic clustering, a product performance lexicon was put forward to determine the clustering topics. The TF-DF method was improved to be used for lexicon creation, and the customer need mining was completed based on the product performance lexicon. Secondly, in view of the lack of customer need analyses processes n current product review research, the product review data based Kano analyses method was proposed. On the basis of above mentioned, matter-element theory was introduced to quantitatively express the customer need model. At last, the feasibility and effectiveness of the proposed methods were verified by a case study. [ABSTRACT FROM AUTHOR]

In recent years, nanomaterial-based drug delivery carriers have become some of the most attractive to be studied. The purpose of this study is to investigate the interaction of C60 fullerene, carbon nanotube and graphene having porphyrin-like FeN4 clusters with a non-steroidal anti-inflammatory drug (ibuprofen) by means of the density functional theory. Results showed that the graphene with FeN4 clusters could remarkably increase the tendency of graphene for adsorption of ibuprofen drug. Also, our ultraviolet–visible results show that the electronic spectra of the complexes exhibit a blue shift toward lower wavelengths (higher energies). It was found that Ibp/FeN4-graphene had high chemical reactivity, which was important for binding of the drug onto the target site. In order to go further and gain insight into the binding features of considered systems with ibuprofen drug, the Atoms in Molecules analysis was performed. Our results determine the electrostatic features of the Ibp/FeN4-graphene bonding. Consequently, the results demonstrated that the FeN4-graphene could be used as potential carriers for the delivery of ibuprofen drug. [ABSTRACT FROM AUTHOR]

Modulated filter bank with low complexity is the key to realize the engineering applications for speech signal processing, multicarrier communication, and wideband digital receivers. The frequency response masking (FRM) technology is an effective method to design finite impulse response filters with narrow transition band (NTB). In this paper, an interpolation FRM unified modulated filter bank (IFRM-UMFB) architecture with NTB is proposed to reduce the computational complexity of the modulated filter bank architecture. The IFRM approach increases the transition band of two masking filters by the interpolation of N and reduces the computational complexity of two masking filters compared with classic FRM approach. The proposed IFRM-UMFB architecture with NTB is suitable for different odd-stacked or even-stacked, maximally decimated or non-maximally decimated structures. The proposed IFRM-UMFB architecture with NTB is verified to be correct through simulation. The complexity comparison result shows that the proposed IFRM-UMFB architecture offers multipliers reduction of 77.4% over the directly design approach and 26.5% over the classic FRM approach. Moreover, the proposed IFRM-UMFB architecture with NTB also can be directly applied to wideband digital receivers with high sampling rate. [ABSTRACT FROM AUTHOR]

The low-complexity channelizer is essential in passive radar multi-channel wideband receiver using array antennas. The digital filter bank is usually used to realize the channelizer. In the paper, a low-complexity channelizer based on frequency response masking (FRM) is proposed to reduce the high computational complexity of the narrow transition bandwidth filter bank. A half-band filter is used to design the prototype filter of the proposed low-complexity channelizer based on FRM. Compared to the maximally decimated filter bank, the decimation coefficient of the non-maximally decimated filter bank can be different from the number of channels, which makes the low-complexity channelizer more flexible. The low-complexity channelizer based on FRM can be directly applied to a wideband receiver without the limit of the sampling rate. The simulation and complexity analysis results show that the proposed low-complexity channelizer is correct and significantly reduces computational and hardware complexities. The proposed low-complexity channelizer makes it possible to implement passive radar multi-channel wideband receiver on a single hardware processor; thus, it is suitable to applied in passive radar multi-channel wideband receiver using array antennas. [ABSTRACT FROM AUTHOR]

Aiming at the locality and uncertainty of observations in large-scale multi-agent application scenarios, the model of Decentralized Partially Observable Markov Decision Processes (DEC-POMDP) is considered, and a novel multi-agent reinforcement learning algorithm based on local communication is proposed. For a distributed learning environment, the elements of reinforcement learning are difficult to describe effectively in local observation situation, and the learning behaviour of each individual agent is influenced by its teammates. The local communication with consensus protocol is utilized to agree on the global observing environment, and thus that a part of strategies generated by repeating observations are eliminated, and the agent team gradually reach uniform opinion on the state of the event or object to be observed, they can thus approach a unique belief space regardless of whether each individual agent can perform a complete or partial observation. The simulation results show that the learning strategy space is reduced, and the learning speed is improved. [ABSTRACT FROM AUTHOR]

In recent years, the improvement of soil cadmium (Cd) contamination remediation effect of biochar by modification has received wide attention. However, the effect of combined modification on biochar performance in soil Cd contamination remediation and the mechanism are still unclear. In this study, cotton straw biochar and maize straw biochar were co-modified by KOH (0, 3, 5 mol L-1), K 3 PO 4 , and urea. Then, two modified biochars with high Cd adsorption capacity were selected to test the soil Cd contamination remediation effect through a pot experiment. The results showed that the combined modification by using KOH, K 3 PO 4 , and urea significantly increased the specific surface area and nitrogen (N) and phosphorus (P) contents of biochar, providing more adsorption sites for Cd. Among the modified biochar, the cotton straw biochar modified with KOH (3 mol L-1), K 3 PO 4 , and urea (m3-CSB) had the highest adsorption capacity (111.25 mg g-1), which was 7.86 times that of cotton straw biochar (CSB). The m3-CSB for adsorption isotherm and kinetics of Cd conformed to the Langmuir model and Pseudo-second-order kinetic equation, respectively. In the pot experiment, under different exogenous Cd levels (0 (Cd0), 4 (Cd4), and 8 (Cd8) mg kg-1), m3-CSB treatment decreased soil available Cd content the most (51.68%–63.4%) compared with other biochar treatments. Besides, m3-CSB treatment significantly promoted the transformation of acid-soluble Cd to reducible, oxidizable, and residual Cd, reducing the bioavailability of Cd. At the Cd4 level, the application of m3-CSB significantly reduced cotton Cd uptake compared to CK, and the maximum reduction of Cd content in cotton fibers was as high as 81.95%. Therefore, cotton straw biochar modified with KOH (3 mol L-1), K 3 PO 4 , and urea has great potential in the remediation of soil Cd contamination. [Display omitted] • Combined modification enhanced the adsorption capacity of straw-derived biochar. • Nitrogen and phosphorus were successfully loaded on MSB through KOH. • Combined modified biochar reduced soil cadmium bioavailability more than biochar. • Combined modified biochar reduced Cd uptake and transport in cotton more than biochar. [ABSTRACT FROM AUTHOR]