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Human activities, such as plant cultivation, enhance the activity concentrations (ACs) of radionuclides in the topsoil and have the potential to affect humans and the environment. The soil with a high radiation background not only acts as a source of continuous radiation exposure to humans but also as a medium of migration for the transfer of radionuclides to food crops. Some spectrometers can measure the AC of radionuclides in the soil, but long‐term variation of AC is difficult to investigate. Therefore, developing methods for predicting the AC of radionuclides in agricultural soil is an interesting topic that many studies have focused on. In this work, a simple method was introduced to estimate long‐term changes of some radioisotopes in the top layer of soil (0–20 cm). The estimation considered four major processes: fertilization, irrigation, vertical leaching, and plant uptake. The leaching rates (Rl) of radionuclides were predicted by their ACs in the soil water and the infiltration rate of water in the soil. The method was applied to the soils of five study fields in southern Vietnam, and the Rl values of 226Ra were between 7.4 Bq·m−2·y−1 and 60 Bq·m−2·y−1, while the rates of 210Po were between 22.1 and 111 Bq·m−2·y−1. For long‐term assessment, it was found that 226Ra increases in sweat potato soil and tomato soil with annual rates (ΔC) of 0.99 Bq·kg−1·y−1 and 0.69 Bq·kg−1·y−1, respectively. The AC of 210Po was predicted to increase in some soils. The corresponding ΔC values for 210Po were 0.028 Bq·kg−1·y−1 in rice, 0.617 Bq·kg−1·y−1 sweet potato, and 0.099 Bq·kg−1·y−1 in tomato soils. The results imply that interventions are necessary to reduce the radioactivity accumulation in fields with high ΔC values. The effective methods can be changing the fertilizer types and the irrigation systems. [ABSTRACT FROM AUTHOR]

Summary: In this paper, we introduce a method for reasoning with words based on hedge algebra using linguistic cognitive map (핃ℂ필). Our model consists of a set of vertices and edges whose values are linguistic variables that are constrained by a linguistic lattice. The algorithm for the system studied consists of fuzzification, reasoning, and defuzzification. Further, the total effect between any two vertices in the 핃ℂ필 is computed. [ABSTRACT FROM AUTHOR]

In order to reduce the impact of renewable energy output and load fluctuations and improve the flexibility of the integrated energy system (IES), it is necessary to further promote user participation in integrated demand response (IDR). Therefore, this paper constructs a hierarchical framework that enables the transaction of IDR resources among users by combining the information interaction network established by blockchain and the energy management network established by energy management system. This paper also analyses the comfort of users, the cost of energy purchase by users and the cost of energy use by load aggregators, and then develops a two‐layer optimization model. The results of the simulation show that the model and trading framework constructed in this paper can realize the trading of IDR resources among users, which effectively promotes the participation of users in IDR, reduces the cost of users and load aggregators, reduces the loss of IDR resources, enables more effective integration of dispersed IDR resources and improves the flexibility of IES. [ABSTRACT FROM AUTHOR]

With the rapid development of carbon trading market, the volatility trend of carbon emission trading price (CETP) becomes one of the factors that cannot be ignored in energy system planning. Based on this, this paper proposes a multi‐objective expansion planning model for park‐level integrated energy system (PIES) that takes into account the volatility trend of CETP. First, the influencing factors of CETP prediction are filtered and downscaled, and a kernel extreme learning machine (KELM) model based on the improved multi‐objective grey wolf algorithm optimizer (IMOGWO) is used for probabilistic interval prediction of CETP. Next, the operational characteristics of each carbon emission device are analysed and a model for calculating the cost of carbon trading is proposed. Then, a two‐layer PIES planning model is developed with the objective of minimizing the annualized system cost and carbon emissions during the expansion planning cycle, the upper‐layer model is a planning model for solving equipment expansion scenarios, and the lower‐layer model is an operation model for calculating typical operation schemes. Finally, the simulation effect of the prediction model is verified by the European carbon trading data, and the planning schemes are compared and analysed to prove the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Arriving on time is of great importance for flight management and passenger experience. One of the essential factors that impacts on-time arrival is the wind condition. Accurate information of wind speed and direction around the fuselage helps to improve the performance of on-time arrival and four-dimensional trajectory (4DT) planning. To determine accurate wind information in real-time, a novel airborne estimation method of wind speed and direction is proposed in this paper. Inertial Navigation System (INS), Global Satellite Navigation System (GNSS), and Air Data System (ADS) are fused in an Unscented Kalman Filter (UKF), which provides great accuracy and robustness in nonlinearity conditions. The dynamic models of wind are established, and implementations of the UKF are detailed. Finally, simulations are designed and the effectiveness of the proposed method is verified through the comparison with the traditional direct measurement method. Results demonstrate that the accuracy of wind speed and direction obtained by our method is nearly two times higher than the traditional direct measurement method. [ABSTRACT FROM AUTHOR]

American ginseng (Panax quinquefolius), one of the most well‐known araliaceous perennial herbs, suffered from root rots and mortality in 2020 in Taibai County, Shaanxi Province, China, leading to 40%–60% yield losses. The diseased plants initially showed unevenly yellowing foliage, and yellow‐brownish, water‐soaked roots with internal softening. Subsequently, white fluffy mycelia manifested on the surface of diseased P. quinquefolius roots, followed by the appearance of black irregular sclerotia‐like bodies. In this study, a fungal isolate (SS‐TB, GenBank no. MT830866) was obtained from the infected roots. Based on the culture morphology, pathogenicity tests and phylogenetic analysis of the internal transcribed spacer (ITS) region, this isolate was identified as Sclerotinia nivalis. The optimum temperature for mycelial growth and sclerotial production was 20 ℃ and 15 ℃, respectively; the optimum pH for mycelial growth and sclerotial production was pH 6.0. This isolate grew faster and produced more sclerotia on potato dextrose agar than on other media. It infected ginseng roots with or without wounds, but inoculation of wounded roots led to more severe disease. S. nivalis also infected 43 of the 48 plant species tested, including vegetables, fruits, oil crops, and flowering plants from Fabaceae, Asteraceae, Solanaceae, Cucurbitaceae, Brassicaceae, Apiaceae, Rosaceae, Liliaceae, Chenopodiaceae, and Orchidaceae. It was nonpathogenic on Triticum aestivum, Zea mays, Anemone vitifolia, Ipomoea batatas, and Vaccinium sp. This study is the first report of S. nivalis causing white rot on P. quinquefolius. [ABSTRACT FROM AUTHOR]

This study aims to investigate chitosan (CS) with five different molecular weight (Mw) on freeze–thaw stability of Arenga pinnata starch (APS) gel subjected to five freeze–thaw cycles (FTC). The syneresis of APS gels was reduced by adding CS and the APS gel with high Mw CS had lower syneresis duo to a higher water holding capacity (P < 0.05). The addition of CS significantly decreased the hardness and molecular ordered structure of APS gel. In addition, CS could improve the microstructural stability. The results suggested that CS could effectively improve the freeze–thaw stability of APS gel, and CS with higher Mw might have more practical utility to improve stability of APS gel. [ABSTRACT FROM AUTHOR]

Levansucrase (EC 2.4.1.10) catalyzes both levan polymerization and sucrose hydrolysis. Levan production by recombinant Bacillus subtilis levansucrase SacB‐T305A was investigated. The maximum conversion yield (33.09%) of sucrose to levan and levan yield (115.8 g L–1) were obtained as 30% (wt/vol) and 40% (wt/vol) initial sucrose, respectively. Under highly acidic conditions (pH 3.5 and below), the polymerization not only shifted distinctly to high molecular weight levan but also enlarged the size of low molecular weight levan. In particular, the proportion of high molecular weight levan to total products increased to 9‐fold at pH 3.5. The presence of Fe2+, Mg2+, Mn2+ and Zn2+ ions at common ion strength (5 mmol L–1) increased only the size of low molecular weight levan from about 20 kDa to about 35 kDa. Our findings provide a supplementary view about the mechanism of levan molecular weight distribution in enzymatic synthesis and offer a possibility for producing levan of different molecular weights by modulating enzymatic reaction conditions. © 2020 Society of Industrial Chemistry [ABSTRACT FROM AUTHOR]

Tiltrotor aircraft possesses redundant actuators in take-off phase and its flight control is more complicated than ordinary aircraft because the structural and dynamic characteristics keep changing due to tilting rotors. One of the fundamental bases for flight control is trim, which provides steady flight states under various conditions and then constructs the reference trajectory. Tiltrotor aircraft trim models are described by multivariate nonlinear equations whose initial values are difficult to determine and bad initials could lead to incorrect solution for flight control. Therefore, an innovative trim method is proposed to solve this issue. Firstly, genetic algorithm (GA), which possesses strong capability in searching global optimum, is adopted to identify a coarse solution. Secondly, the coarse solution is further refined by the Levenberg-Marquardt (LM) method for precise local optimum. The innovative trim method combines the advantages of these two algorithms and is applied to a tiltrotor aircraft's flight control in the transition process of incline take-off. The limitation of trajectory is discussed, and tilt corridor is constructed. Finally, the incline take-off simulations are conducted and the effectiveness of the proposed trim method is verified through good match with the designed reference trajectory. [ABSTRACT FROM AUTHOR]

As the development of the energy industry, the integration and complementary of various energy resources will be trends of future multiple energy systems. Energy hub (EH) plays an important role in allocating energy resources efficiently. This study proposes a robust coalitional game theoretic optimisation model to execute the cooperative operation of multiple EHs with correlated wind power. First, an EH model with wind power generation is established. It considers both uncertainties and correlations of wind power. Then, coalitional game theory is introduced to solve the cooperation problem of multiple EHs. Distributed coalition formation algorithm called merge–split rule is developed to form coalitions of EHs. Furthermore, the robust optimisation method is presented to cope with the uncertainties of wind power. Scenarios of correlated historical data are covered by minimum volume enclosing ellipsoid and solved by Khachiyan's first‐order algorithm. Numerical results are given to verify the feasibility and efficiency of our proposed models and methods. [ABSTRACT FROM AUTHOR]

The growing utilisation of natural gas and renewable energy resources brings more challenges to generation expansion planning problems. Short‐term operational constraints are equally important for long‐term capacity planning. This work studies the interdependence between electricity and natural gas systems and presents a combined market mechanism that allows two‐stage energy trading and planning based on asynchronous electricity and gas markets. In the first stage, the gas market is cleared with the objective of maximum social welfare (lower level), at the same time obtaining the optimal strategies offered by gas producers and gas‐fired units (upper level). In the second stage, generation companies and consumer companies aim to maximise their corresponding profits in the planning horizon (upper level), and electricity market is cleared on principle of maximum social welfare (lower level). Then, the authors develop a modified alternative direction method of multiplier algorithm to solve the two‐stage nested bilevel model. To improve operational flexibility of expansion plans, uncertainties of renewable energy generation and integrated demand response are also included and analysed in different risk scenarios. Case studies validate the effectiveness of the proposed methodology. [ABSTRACT FROM AUTHOR]

Involvement of active distribution networks (ADNs) in emission management can give full play to the carbon-reduction potential of distributed generations (DGs) and demand response. With the development of smart grid, low-carbon coordinated scheduling of power system with ADNs will become a new trend. A bilevel dispatch model based on locational marginal emission (LME) is proposed to achieve carbon reduction from both generation and load sides. The main grid dispatch is a problem of dynamic optimal power flow aiming at reducing both the operating and emission costs, in which LME under AC condition is adopted to calculate the carbon emission produced by node power. The ADN level is the DG generation schedule with the objective of minimizing both the cost and system emission based on LME. The main grid and ADNs interact and cooperate with each other by locational marginal price (LMP) and LME to cut the carbon pollution. Simulation results in a modified IEEE 30-bus system and an IEEE 118-bus system show that compared with the traditional LMP-based coordinated scheduling, the bilevel dispatch model based on LME can reduce carbon emission effectively and promote ADNs' participation in system carbon emission management. © 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Oxaliplatin (OXA) was coupled to PEGylated polyamidoamine dendrimers of fourth generation (G4‐PEG@OXA) in the comparison to PEGylated ones of odd generation (G3.5‐PEG@OXA). Proton nuclear magnetic resonance and Fourier‐transform infrared spectroscopy were used to confirm the successful incorporation of OXA as well as the synthesis of carrier systems. Both two types of carrier systems exhibited in sphere nanoparticle shape with size of less than 100 nm that was in the range being able to cause toxicity on cancer cells. The average drug loading efficiency (DLE) of G4‐PEG@OXA was obtained at 84.63% that was higher than DLE of G3.5‐PEG of 75.69%. The release kinetic of G4‐PEG@OXA and G3.5‐PEG@OXA did not show any burst release phenomenon while free OXA was released over 40% at the first hour. The sustainable release of OXA was achieved when it was encapsulated in these carriers, but the G4 generation liberated OXA (3.4%‐6.4%) slower than G3.5 one (11.9%‐22.8%). The in vitro cytotoxicities of G4‐PEG@OXA were evaluated in HeLa cell lines using resazurin assay and live/dead staining test. Although the free OXA showed a rather moderate killing ability, the G4‐PEG@OXA still displayed the low viability of HeLa that was better to the result of G3.5‐PEG@OXA due to released OXA amount. The benefit of this system was to overcome the burst release phenomenon to minimize OXA toxicity without compromising its efficiency. [ABSTRACT FROM AUTHOR]

The title compounds are prepared by three-component cyclocondensation of phtalhydrazide, benzaldehydes, and malononitrile or ethyl cyanoacetate under environmentally friendly conditions. [ABSTRACT FROM AUTHOR]