Automatic Label Sequence Generation for Prompting Sequence-to-sequence Models

Prompting, which casts downstream applications as language modeling tasks, has shown to be sample efficient compared to standard fine-tuning with pre-trained models. However, one pitfall of prompting is the need of manually-designed patterns, whose outcome can be unintuitive and requires large validation sets to tune. To tackle the challenge, we propose AutoSeq, a fully automatic prompting method: (1) We adopt natural language prompts on sequence-to-sequence models, enabling free-form generation and larger label search space; (2) We propose label sequences -- phrases with indefinite lengths to verbalize the labels -- which eliminate the need of manual templates and are more expressive than single label words; (3) We use beam search to automatically generate a large amount of label sequence candidates and propose contrastive re-ranking to get the best combinations. AutoSeq significantly outperforms other no-manual-design methods, such as soft prompt tuning, adapter tuning, and automatic search on single label words; the generated label sequences are even better than curated manual ones on a variety of tasks. Our method reveals the potential of sequence-to-sequence models in few-shot learning and sheds light on a path to generic and automatic prompting. The source code of this paper can be obtained from https://github.com/thunlp/Seq2Seq-Prompt.Comment: Accepted to COLING 202

A Method of Two-Stage Pressure Control Based on Multistage Orifices

The interaction of pressure and flow in a hydraulic system with multiple working conditions, multiple actuators, and large flow limits action adjustment and control. Through a pilot pressure control circuit, hydraulically operated valves can adjust pressure or direction more effectively. A recent study proposed a two-stage pressure control method based on multistage orifices and solenoid valves. The requirements of the number and diameter ratio of short orifices in the series to realize the two-stage pressure control were theoretically analyzed. Scheme design and experiment were carried out. The influence of structures of complex flow channel and solenoid valve on the higher or lower pilot control pressure was considered in the experiment. The method was experimentally verified and successfully applied in a turbine electrohydraulic control system with lower maintenance costs, making the system more reliable in the case of electrical failure. Research results provide insight into pilot pressure control in fluid systems using multistage orifices to achieve either higher or lower pressure. In addition, it has important guiding significance for the design of valves or engineering systems based on pilot hydraulic pressure

Application of Variable Weight Coefficient Method in State Evaluation of AC Contactor

AC contactor state evaluation is a challenging problem. This paper proposes an AC contactor state assessment method based on variable weight coefficient. Firstly, the characteristic indicators that have a great influence on the state of the AC contactor are selected, and the state evaluation index system is established. Secondly, using the subjective and objective combination weighting method combined with the analytic hierarchy process and the grey relational analysis method, the constant weight coefficient is obtained, and the variable weight coefficient method with the equalization function is introduced to obtain the variable weight coefficient of each characteristic parameter. Finally, the fuzzy comprehensive evaluation method is used to evaluate the running state of the AC contactor. The experimental results show that the state evaluation method proposed in this paper can accurately reflect the real state of the AC contactor operation and effectively improve the reliability of the power system

Application of Variable Weight Coefficient Method in State Evaluation of AC Contactor

AC contactor state evaluation is a challenging problem. This paper proposes an AC contactor state assessment method based on variable weight coefficient. Firstly, the characteristic indicators that have a great influence on the state of the AC contactor are selected, and the state evaluation index system is established. Secondly, using the subjective and objective combination weighting method combined with the analytic hierarchy process and the grey relational analysis method, the constant weight coefficient is obtained, and the variable weight coefficient method with the equalization function is introduced to obtain the variable weight coefficient of each characteristic parameter. Finally, the fuzzy comprehensive evaluation method is used to evaluate the running state of the AC contactor. The experimental results show that the state evaluation method proposed in this paper can accurately reflect the real state of the AC contactor operation and effectively improve the reliability of the power system

Complex Dynamics on the Routes to Chaos in a Discrete Predator-Prey System with Crowley-Martin Type Functional Response

We present in this paper an investigation on a discrete predator-prey system with Crowley-Martin type functional response to know its complex dynamics on the routes to chaos which are induced by bifurcations. Via application of the center manifold theorem and bifurcation theorems, occurrence conditions for flip bifurcation and Neimark-Sacker bifurcation are determined, respectively. Numerical simulations are performed, on the one hand, verifying the theoretical results and, on the other hand, revealing new interesting dynamical behaviors of the discrete predator-prey system, including period-doubling cascades, period-2, period-3, period-4, period-5, period-6, period-7, period-8, period-9, period-11, period-13, period-15, period-16, period-20, period-22, period-24, period-30, and period-34 orbits, invariant cycles, chaotic attractors, sub-flip bifurcation, sub-(inverse) Neimark-Sacker bifurcation, chaotic interior crisis, chaotic band, sudden disappearance of chaotic dynamics and abrupt emergence of chaos, and intermittent periodic behaviors. Moreover, three-dimensional bifurcation diagrams are utilized to study the transition between flip bifurcation and Neimark-Sacker bifurcation, and a critical case between the two bifurcations is found. This critical bifurcation case is a combination of flip bifurcation and Neimark-Sacker bifurcation, showing the nonlinear characteristics of both bifurcations

Blueberry and mulberry juice prevent obesity development in C57BL/6 mice.

OBJECTIVES:To establish whether blueberry (Vaccinium ashei) and mulberry (Morus australis Poir) juice, anthocyanin rich fruit juice, may help counteract obesity. DESIGN:And Methods: Four-week-old C57BL/6 mice were fed a high-fat diet (HFD) with or without blueberry and mulberry juice for 12 weeks. Body weight, serum and hepatic lipids, liver and adipose tissues morphology, insulin and leptin were assessed. RESULTS:Mice fed HFD exhibited increased body weight, insulin resistance, serum and hepatic lipids. In comparison, blueberry and mulberry juice inhibited body weight gain, decreased the serum cholesterol, reduced the resistance to insulin, attenuated lipid accumulation and decreased the leptin secretin. CONCLUSION:These results indicate that blueberry and mulberry juice may help counteract obesity

Regular and Irregular Vegetation Pattern Formation in Semiarid Regions: A Study on Discrete Klausmeier Model

The research on regular and irregular vegetation pattern formation in semiarid regions is an important field in ecology. Applying the framework of coupled map lattice, a novel nonlinear space- and time-discrete model is developed based on discretizing the classical Klausmeier model and the vegetation pattern formation in semiarid regions is restudied in this research. Through analysis of Turing-type instability for the discrete model, the conditions for vegetation pattern formation are determined. The discrete model is verified by Klausmeier’s results with the same parametric data, and shows advantages in quantitatively describing diverse vegetation patterns in semiarid regions, such as the patterns of regular mosaicirregular patches, stripes, fractured stripesspots, and stripes-spots, in comparing with former theoretical models. Moreover, the discrete model predicts variations of rainfall and vegetation types can cause transitions of vegetation patterns. This research demonstrates that the nonlinear mechanism of the discrete model better captures the diversity and complexity of vegetation pattern formation in semiarid regions

Modulating Structure Ordering via Side-Chain Engineering of Thieno[3,4-b]thiophene-Based Electron Acceptors for Efficient Organic Solar Cells with Reduced Energy Losses

Nonfullerene-based organic solar cells (OSCs) have made a huge breakthrough in the recent years. Introducing a proper side chain on the pi-conjugated backbone plays a vital role for further improving the power conversion efficiency (PCE) of OSCs due to easy tuning of the physical properties of the molecule such as absorption, energetic level, solid-state stacking, and charge transportation. More importantly, the side chain significantly affected the blend film's morphology and thus determined the PCEs of the devices. In this work, two low-band-gap nonfullerene acceptors, ATT-4 and ATT-5, with an alkyl or branched alkyl substitute on indacenodithiophene (IDT) and thieno[3,4-b]thiophene (TbT) backbone were synthesized for investigating the effect of the substituent on the performance of the nonfullerene acceptors (NFAs). In comparison to ATT-1 with p-hexylphenyl-substituted IDT and n-octyl-substituted TbT moieties, ATT-4 and ATT-5 exhibit better crystallinity with shorter interchain distance and ordered molecular structure in neat and the corresponding blend films. The tailored ATT-5 exhibits a high PCE of 12.36% with a V-oc of 0.93 V, J(sc) of 18.86 mA cm(-2), and fill factor (FF) of 0.71, blending with a wide-band-gap polymer donor PBDB-T. Remarkably, although ATT-4 and ATT-5 exhibit broader light absorption, the devices obtained higher V-oc than that of ATT-1 mainly due to the reduced nonradiative recombination in the blend films. These results implied that side-chain engineering is an efficient approach to regulate the electronic structure and molecular packing of NFAs, which can well match with polymer donor, and obtain high PCEs of the OSCs with improved V-oc, J(sc), and FF, simultaneously