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More recently, soft actuators have evoked great interest in the next generation of soft robots. Despite significant progress, the majority of current soft actuators suffer from the lack of real‐time sensory feedback and self‐control functions, prohibiting their effective sensing and multitasking functions. Therefore, in this work, a near‐infrared‐driven bimorph membrane, with self‐sensing and feedback loop control functions, is produced by layer by layer (LBL) assembling MXene/PDDA (PM) onto liquid crystal elastomer (LCE) film. The versatile integration strategy successfully prevents the separation issues that arise from moduli mismatch between the sensing and the actuating layers, ultimately resulting in a stable and tightly bonded interface adhesion. As a result, the resultant membrane exhibited excellent mechanical toughness (tensile strengths equal to 16.3 MPa (||)), strong actuation properties (actuation stress equal to 1.56 MPa), and stable self‐sensing (gauge factor equal to 4.72) capabilities. When applying the near‐infrared (NIR) laser control, the system can perform grasping, traction, and crawling movements. Furthermore, the wing actuation and the closed‐loop controlled motion are demonstrated in combination with the insect microcontroller unit (MCU) models. The remote precision control and the self‐sensing capabilities of the soft actuator pave a way for complex and precise task modulation in the future. A light‐driven and self‐sensing intelligent bilayer soft actuator, the PM‐liquid crystal elastomer (LCE), built with LCE, MXene, and Poly(dimethyldiallylammonium chloride) (PDDA) is prepared through the layer‐by‐layer self‐assembly strategy; moreover, the high‐precision, self‐sensing and feedback loop control functions are realized. Furthermore, a PM‐LCE‐based closed‐loop control system is also demonstrated.

Hexaploid triticale, including its primary and secondary forms, is an important forage crop and a promising energy plant. Primary forms are usually developed by crossing Triticum turgidum L. with rye, with secondary forms obtained by crossing primary hexaploid triticale and/or hexaploid wheat with octoploid triticale. In this study, we developed an effective method for production of hexaploid triticale via hybridization of synthetic hexaploid wheat (SHW) with rye. The three employed SHW lines were derived from hybridization of T. turgidum with Aegilops tauschii Cosson, and inherited meiotic restitution genes, which can promote the formation of functional gametes in haploid status, from their T. turgidum parents. Although the resulting tetraploid F 1 hybrids with rye (genome ABDR) produced amphiploids (octoploid triticale) and partial amphiploids, the final hybrid products obtained through fertility selection over several generations were hexaploids. These hexaploids were the result of preferential elimination of D-genome chromosomes. In addition to complete hexaploid triticale with 28 intact A/B and 14 intact R chromosomes, we obtained hexaploid triticales with other chromosome constitutions, including monosomic, substitution, and translocation lines. Chromosomes 2D and 5D from the wild species A. tauschii were incorporated into the hexaploid triticales. Out of eight analyzed stable lines derived from three different SHW-L1/rye F 1 plants, we observed four lines with small-fragment translocations between wheat and rye chromosomes. Rapid production of hexaploid triticales using this method involves two factors: (1) hybridization between hexaploid wheat with a meiotic restitution gene(s) and rye and (2) selection for good fertility during F 3 and subsequent generations.

As key equipment in nuclear power plant, the reactor power control system is adopted to strictly control and regulate the reactor power of a PWR (pressurized water reactor) in a nuclear power plant. A well-optimized predictive control algorithm based on SDMC (stepped dynamic matrix controller) is developed and introduced in this paper and applied to the power regulation of a reactor power model. In addition, the test and verification of this application is conducted by two different methods and devices: the virtual verification platform and the physical DCS (digital control system). The result of the verification suggests that the application of SDMC gains a better performance in the maximum dynamic deviation, adjustment time, overshoot, and so on.

Nonlocal prey competition, which describes that intra-prey competition is not only dependent on a location in space but also related to entire space, is introduced to a prey–predator model involving fear effect and digest delay. In the nonlocal prey competition model, the critical delay threshold increases with the increasing of the fear level or the intra-prey competition coefficient. In addition, in the case that the intra-prey competition coefficient is less than the threshold, local and nonlocal prey competition models admit the same critical delay threshold. However, in the case that the intra-prey competition coefficient is beyond the threshold, the critical delay threshold for nonlocal prey competition is less than local prey competition. Moreover, nonlocal prey competition term can drive Hopf bifurcation for spatially inhomogeneous form, and the spatially inhomogeneous periodic solution emerges. It is worth noting that in the absence of delay, nonlocal prey competition model can undergo spatially inhomogeneous Hopf bifurcation and Turing instability by diffusion, but local prey competition can not occur. Numerical simulations verify the theoretical analysis. Also, under the influence of nonlocal effect, the amplitude of the spatially homogeneous periodic solution becomes larger. Meanwhile, nonlocal effect may increase the risk of extinction for two species to a certain extent.

In this paper, the mode density, coupling coefficient, eigenfrequencies, quality factors and starting currents of a 170 GHz cylindrical and confocal gyrotron are studied based on the linear theory. Results show that the mode density in the confocal cavity greatly decrease due to the diffraction properties. Modes in the confocal cavity have lower quality factors than the modes in cylindrical cavity, hence the starting currents are higher than the latter. The confocal gyrotron is more stable than the cylindrical gyrotron when operating at large current. Meanwhile, through altering the mirror width, quality factors together with the starting current of the confocal modes are adjustable.

Lanthanum-modified bentonite (LMB, Phoslock ® ) is a well-known capping agent for phosphorus immobilization in sediments. Herein, LMB was used to immobilize As in sediments. Batch capacity experiments for arsenate and arsenite adsorption were carried out to obtain adsorption isotherms and kinetics using the Langmuir and Freundlich model calculations. High-resolution (HR) diffusive gradients in thin films (DGT) were applied to monitor the changes of weakly bound As fraction near sediment–water interface (SWI). The interaction of As(III) and As(V) with LMB was influenced by pH and initial mineral composition. As(V) was more obviously adsorbed than As(III) at pH 4 to 9, with mean adsorption of 3.89 mg g −1 and 0.04 mg g −1 , respectively, while at pH > 9 As(III) was preferentially adsorbed. After LMB amendment for 2 months, the maximum As removal efficiency in the pore and overlying water reached 84.5% and 99.3%, respectively. The capping agent remained stable in the top sediments, while the maximum DGT labile As content decreased to 0.89 and 0.51 μg L −1 in dosage-and time-treatments. The As concentration inflection point moved down to a deeper layer. As species changed from labile exchangeable–As to Fe–oxide–bound and residual As. The proportion of mobile As finally decreased to 10.5% of the total As in the upper 20-mm layer sediment. The increase of K d (the distribution coefficient at SWI) and k 1 (adsorption rate constant) and the decrease of T c (response time of (de)sorption) in the DGT–induced fluxes model (DIFS) indicated the time-dependent impediment of As release from the sediment due to LMB immobilization.

Observing a fast-evolving world economy and agricultural financial system, this dissertation studies three emerging questions in agricultural finance: agricultural financial technology (FinTech), blockchain and cryptocurrencies; persistence and growth of religious farming communities that limit use of technology in the U.S.; and livestock insurance willingness to offer in China. These emerging questions and developments fit closely into the top priority of the G20 Global Partnership for Financial Inclusion (GPFI), and the vital tools recognized to meet the Sustainable Development Goals (SDGs) set by the United Nations. These emerging agricultural finance strategies are crucial to improve agricultural value chain, reduce inequality, and spur economic growth, especially for rural areas with intensive agricultural activities. These topics are sparsely studied empirically due to limited data, evolving policies, and rapidly changing technologies. In this thesis I take the initiative to understand these both qualitatively and quantitatively. The first chapter discusses the overall importance of these emerging areas of agricultural finance strategies to support the development of the agricultural economy. We provide background domain knowledge on Agricultural FinTech with an emphasis to blockchain and cryptocurrencies, elaborating the applications of blockchain in food and agriculture value chain and supply chain, that improves the transparency and efficiency of tracing and trading. Understanding the relationship between blockchain and cryptocurrencies is crucial to applications of this technology in agriculture, thus we relay quantitative research to the more practically operated cryptocurrencies to understand its market property. Chapter 2 examines the financial property of 3,351 cryptocurrency price series, particularly looking at the long or short memory within its price series and evaluate if they follow a fractional Brownian motion through Hurst estimators and Stepwise autoregression. We investigate the releasing mechanism of Bitcoin and use top 105 coins’ supply structure to explain the memory in their price series, for which we find the % of total coins issued is explanatory. Due to concerns of supply related built-in memory within the price series, we propose a de-mean method to decompose the price series with the time varying mean and the variations, and we found that some previously found long memory was actually spurious. The gradually increasing (time-varying) mean can explain this spuriousness, and we use the market structure such as the 4-year bull circle and the deflationary releasing mechanism to explain this time-varying phenomenon. The findings of this chapter confirm the fractionality of crypto markets generally, and provide clarity of true or spurious long memory using both traditional and advanced methods. This enhances our understanding of these emerging financial assets that could potentially be applied to agricultural value chains. One possibility is a blockchain token system that is linked to warehouse receipts and enables the holding and trading of grains electronically. The third chapter looks at Amish population growth and how that could affect farmland prices. The Amish culture promotes strong family ties and human-nature interactions; thus, they generally use less modern agricultural production technology. We conceptualize the co-existence of different farming styles between Amish farmers and conventional farmers, to explain how the less productive Amish farmers can stay competitive. The main rationale is that the effectively cheaper labor costs of Amish due to their larger families can compensate the disadvantage from less output due to their limited use of farming technologies. Simply speaking, Amish may have lower revenue, though their costs are low as well, so they could maintain the similar level of profits to their non-Amish neighbors. Because farmland is the most important farm asset class, we hypothesize that any differences in profitability of farming systems would be reflected in farmland prices and analyze whether farmland prices are influenced by Amish population growth. We use a standard hedonic approach and unique shift-share like instrumental variable in this empirical model and find no statistically significant relationship between Amish population growth and farmland prices. Therefore, we infer that Amish compete on the farmland markets similar as the conventional farmers, which aligns with our conceptual framework scenario of similar profitability. This chapter does not only offer insights into the coexistence of multiple farming systems in one market, represented in the farmland market; but also, methodologically showcases how an identification strategy from the labor literature can be applied to agriculture finance issues. The fourth chapter presents our work in investigating agricultural insurance agents’ willingness to offer (WTO) livestock insurance in China, through an in-the-field discrete choice experiment (DCE). We include eight main attributes of livestock insurance and contain various combinations of different levels of them on the choice cards. We implemented the analysis in 6 blocks, with 35 insurance agents in each block. We ask each of them to respond to 15 cards, on each card choose from one of the two hypothetically designed livestock insurance. The card choice combinations of various attributes and levels are designed using JMP software through a D-optimal approach, which use limited sets of choices to maximize the choice exposures to participants and reveal their utility changes when they decide the trade-offs between two choices on the cards based on the different attribute levels included. Premium subsidy and insurance types are two out of eight attributes we primarily study and also find strong clear evidence on. We find that a one level (10%) increase of subsidy lead agents’ probability to offer be 3.166 times higher. We also find the more traditional type, mortality insurance, is still strongly preferred than the newer introduced insurance, with weather-based index insurance being the least preferred, because of farmers’ difficulty in understanding and conflicts when basis risk occurs. Through using survey question to generate interaction term model, we also find knowledge to the newer type of the insurance products improves the WTO on that particular insurance type. This chapter is among the very first to study the supply side of agriculture insurance, and the DCE method we use is a recently popularized method in evaluating insurance products and participants preferences with designs of attributes variations. Our research provides important policy implications as the government and insurance companies work out the details in enlarging the take-up of insurance via interventions of subsidy, education, and innovative /diverse product offering.

Purpose This paper investigates Chinese agricultural insurance agents willingness to offer (WTO) livestock insurance based on the variations of eight main attributes of livestock insurance.Design/methodology/approach This study implements discrete choice experiments (DCE) with actual insurance agents who design, sell and operate livestock insurance in China. The choice experiment of this study is based on the D-optimal approach, a six-block design, with 15 cards per block and two choices per card. The sample size was 211. Econometrics results are based on conditional and mixed logit models.Findings The authors find that the subsidy effect is enormous; a one level increase of subsidy leads to 3.166 times higher probability to offer. This subsidy effect is important as it confirms the endogenous structure between price and quantity in insurance offering, where subsidy does not only incentivize demand but also the supply. Another main factor of insurance investigated is the impact of different coverage types on agents' WTO. The authors find that agents prefer mortality insurance the most, followed by revenue insurance and profit insurance, while Index-Based Livestock Insurance (IBLI) is the least preferred to offer. Agents' knowledge about these newer types of insurance supports their WTO as well; thus, proper education is necessary to promote the more advanced types of livestock insurance.Research limitations/implications A limitation is that in the presence of COVID 19, and administrative issues at the local level, the sample was not randomly drawn. Nonetheless, the authors believe that there is enough diversity across participants, insurers and provinces and have done sufficient robustness checks to support results and conclusions.Practical implications This study provides further validation for the DCE research method that could potentially be applied to different analyses: using choice experiments to study insurers and reveal their preferences, through combinations of various levels of core attributes for insurance products. The findings and contribution are critical to the reform and improvement of livestock insurance in China and for insurance markets more broadly. The authors find that insurers do not place equal weights or values on insurance product attributes and do not view types of insurance equally. In other words, while farmers may hold different preferences about the type of insurance they demand, the results suggest that insurers also hold preferences in the type of insurance they sell.Originality/value So far as the authors are aware, this is the first DCE designed around the supply of insurance products with the subjects being insurance agents, marketers and executives.

Hydrogenation of ethylene carbonate (EC) to co-produce methanol (MeOH) and ethylene glycol (EG) offers an atomically economic route for CO2 utilization. Herein, aided with bench and pilot plant data, we established engineering a kinetics model and multiscale reactor models for heterogeneous EC hydrogenation using representative industrial-type reactors. Model-based analysis indicates that single-stage adiabatic reactors, despite a moderate temperature rise of 12 K, suffer from a narrow operational window delimited by EC condensation at lower temperatures and intense secondary EG hydrogenation at higher temperatures. Boiling water cooled multi-tubular reactors feature near-isothermal operation and exhibit better operability, especially under high pressure and low space velocity. Conduction oil-cooled reactors show U-type axial temperature profiles, rendering even wider operational windows regarding coolant temperatures than the water-cooled reactor. The revelation of operational characteristics of EC hydrogenation under industrial conditions will guide further improvement in reactor design and process optimization.

A double anode magnetron injection gun (MIG) for a 0.42 THz second harmonic gyrotron has been presented in this paper. Through design, simulation and optimization by the particle-in-cell code, a double-anode electron gun with maximum transverse velocity spread of 3.19 % is obtained, the beam acceleration voltage is 50 kV, operating current is 5.5 A and the ratio of the transverse velocity to the axial velocity is equal to 1.4. A comprehensive analysis of MIG for 0.42 THz second harmonic gyrotron is presented, and the designed electron gun well satisfies the requirement of the 0.42 THz gyrotron.