Improving Prompt Tuning with Learned Prompting Layers

Prompt tuning prepends a soft prompt to the input embeddings or hidden states and only optimizes the prompt to adapt pretrained models (PTMs) to downstream tasks. The previous work manually selects prompt layers which are far from optimal and failed to exploit the potential of prompt tuning. In this work, we propose a novel framework, \underline{S}elective \underline{P}rompt \underline{T}uning (SPT), that learns to select the proper prompt layers by inserting a prompt controlled by a learnable probabilistic gate at each intermediate layer. We further propose a novel bi-level optimization framework, SPT-DARTS, that can better optimize the learnable gates and improve the final prompt tuning performances of the learned prompt layer settings. We conduct extensive experiments with ten benchmark datasets under the full-data and few-shot scenarios. The results demonstrate that our SPT framework can perform better than the previous state-of-the-art PETuning baselines with comparable or fewer tunable parameters.Comment: Accepted by EMNLP-202

Entity Linking for Queries by Searching Wikipedia Sentences

We present a simple yet effective approach for linking entities in queries. The key idea is to search sentences similar to a query from Wikipedia articles and directly use the human-annotated entities in the similar sentences as candidate entities for the query. Then, we employ a rich set of features, such as link-probability, context-matching, word embeddings, and relatedness among candidate entities as well as their related entities, to rank the candidates under a regression based framework. The advantages of our approach lie in two aspects, which contribute to the ranking process and final linking result. First, it can greatly reduce the number of candidate entities by filtering out irrelevant entities with the words in the query. Second, we can obtain the query sensitive prior probability in addition to the static link-probability derived from all Wikipedia articles. We conduct experiments on two benchmark datasets on entity linking for queries, namely the ERD14 dataset and the GERDAQ dataset. Experimental results show that our method outperforms state-of-the-art systems and yields 75.0% in F1 on the ERD14 dataset and 56.9% on the GERDAQ dataset

A systematic literature review of computer ethics issues

Given the importance and concern of computer ethics, four issues have been identified in the field of computer and Information Technology (IT). This study was carried out to review the work done on computer ethics issues for the years 2010 to 2014. This paper identifies the methods used, topics addressed, and the main findings published of the research about ethical issues in computer usage. Systematic literature review (SLR) has been conducted according to the standard guidelines, and a study protocol was applied to answer three research questions: 1) What are the ethical issues in computer ethics that have been discussed in previous research?, 2) What are the most recent topics among computer ethics issues?, and 3) To what extent does investigation among IT students, Non-IT students and IT professionals display different perceptions of IT issues? Based on the evidence extracted from 40 studies, it has been clearly stated that software piracy in Privacy, Accuracy, Property and Accessibility (PAPA) and general issues are the topics most frequently discussed. It shows the gaps in the current literature pertaining to computer ethical issues and in particular, the issue of software piracy

Mobility enhancement and highly efficient gating of monolayer MoS2 transistors with Polymer Electrolyte

We report electrical characterization of monolayer molybdenum disulfide (MoS2) devices using a thin layer of polymer electrolyte consisting of poly(ethylene oxide) (PEO) and lithium perchlorate (LiClO4) as both a contact-barrier reducer and channel mobility booster. We find that bare MoS2 devices (without polymer electrolyte) fabricated on Si/SiO2 have low channel mobility and large contact resistance, both of which severely limit the field-effect mobility of the devices. A thin layer of PEO/ LiClO4 deposited on top of the devices not only substantially reduces the contact resistance but also boost the channel mobility, leading up to three-orders-of-magnitude enhancement of the field-effect mobility of the device. When the polymer electrolyte is used as a gate medium, the MoS2 field-effect transistors exhibit excellent device characteristics such as a near ideal subthreshold swing and an on/off ratio of 106 as a result of the strong gate-channel coupling.Comment: 17 pages, 4 figures, accepted by J. Phys.

Echocardiographic parameters versus CHA2DS2-VASc score in prediction of overall cardiac events, heart failure, and stroke in non-valvular atrial fibrillation

     Background: Apart from stroke, atrial fibrillation (AF) is associated with higher mortality and heart failure (HF), in which risk stratification scheme is lacking. Therefore this investigation examined the prognostic value of echocardiographic predictors against CHA2DS2-VASc score in permanent non- -valvular AF (NVAF). Methods: In 252 asymptomatic or mildly symptomatic consecutive patients with NVAF, comprehensive echocardiography was performed. Left atrial deformation parameters were also obtained by two-dimen­sional speckle tracking echocardiography. End-points pertaining to HF deterioration, ischemic stroke and cardiac death were recorded. Results: There were 74 cardiovascular events, including 44 deterioration of HF, 22 ischemic strokes and 8 cardiovascular deaths during an average follow-up period of 20.8 ± 13.5 months (interquartile range, 8–31 months). For prediction of overall prognosis and HF, left ventricular mass index, peak early filling velocity (E), and E to tissue Doppler mitral annular early diastolic velocity ratio (E/e’) outper­formed CHA2DS2-VASc score in multivariate analysis, area under curve, and stepwise nested regression models. Left ventricular hypertrophy and E/e’ > 8 showed worse overall and heart-failure free survival in Kaplan-Meier curves. For prediction of ischemic stroke, the addition of E or E/e’ to CHA2DS2-VASc score provides extra prognostic value. Conclusions: Echocardiographic parameters offer incremental value over CHA2DS2-VASc score for prediction of future cardiac events in NVAF. (Cardiol J 2018; 25, 1: 60–71

Swept blade influence on aerodynamic performance of steam turbine nozzle cascades

To improve the aerodynamic performance of steam turbine nozzle cascades, it is significant to study the effect of swept blades to control the flow field within the cascade. Numerical simulations of three different sweep angle blades (−20°, +20° and 0°) were carried out, using CFD modelling. Simulation results showed that the aft-swept blade can effectively improve the corresponding flow characteristics and reduce the total pressure loss. Meanwhile, it has better aerodynamic performance than the straight blade and the fore-swept blade