Learning to Write with Coherence From Negative Examples

Coherence is one of the critical factors that determine the quality of writing. We propose writing relevance (WR) training method for neural encoder-decoder natural language generation (NLG) models which improves coherence of the continuation by leveraging negative examples. WR loss regresses the vector representation of the context and generated sentence toward positive continuation by contrasting it with the negatives. We compare our approach with Unlikelihood (UL) training in a text continuation task on commonsense natural language inference (NLI) corpora to show which method better models the coherence by avoiding unlikely continuations. The preference of our approach in human evaluation shows the efficacy of our method in improving coherence.Comment: 4+1 pages, 4 figures, 2 tables. ICASSP 2022 rejecte

The impact of writing on academic performance for medical students

Abstract Background Writing is a useful learning activity that promotes higher-order thinking, but there are limited studies that prove its effectiveness. In previous research, researchers tested the effect of summary writing on students comprehension and found no significant difference from that of re-studying texts. The purpose of this study, therefore, is to expand previous findings and investigate the effect of two types of writing tasks on medical students academic performance, specifically in the transfer of knowledge. Methods An experiment was conducted with 139 medical students from Seoul National University College of Medicine. They were randomly assigned to three study conditions: self-study (SS), expository writing (EW), and argumentative writing (AW) group. Each group studied the given material by the method they were assigned, and they were tested on their comprehension and transfer of knowledge using rote-memory type items and transfer type items respectively. Results The results showed that the two writing groups displayed better performance than the SS group in transfer type items, while there was no difference in scores between the EW and AW group. However, the three groups showed no significant difference in their scores for rote-memory type items. Also, there was a positive correlation between the writing scores and transfer type item scores in the AW group. Conclusions This study provides empirical evidence for writing to be adopted in medical education for greater educational benefits. Our findings indicate that writing can enhance learning and higher-order thinking, which are critical for medical students

Active learning through discussion: ICAP framework for education in health professions

Background The ICAP framework based on cognitive science posits four modes of cognitive engagement: Interactive, Constructive, Active, and Passive. Focusing on the wide applicability of discussion as interactive engagement in medical education, we investigated the effect of discussion when it was preceded by self-study and further investigated the effect of generating questions before discussions. Methods This study was conducted in the second semester of 2018 and was participated in by 129 students majoring in health professions, including medicine, dentistry, veterinary medicine, and nursing. The students were assigned to four different trial groups and were asked to fill out a Subjective Mental Effort Questionnaire after completing each session. Their performance in posttest scores was analyzed using Bonferroni test, and mental effort was analyzed using mediation analysis. Results These results indicated that the self-study and question group had the highest performance and that the lecture and summary group had the lowest performance when comparing the total score. Using the analysis of mental effort, it was confirmed that the relationship between different study conditions and post-test performance was mediated by mental effort during test. Conclusions Our findings support the ICAP framework and provide practical implications for medical education, representing the fact that students learn more when they are involved in active learning activities, such as self-study and question generation, prior to discussions.This work was supported by Research Resettlement Fund, funded by Seoul National University to allow the new faculty to design and develop new teaching and learning paradigms in higher education

Asymptotic expressions for turbulent burning velocity at the leading edge of a premixed flame brush and their validation by published measurement data

This paper presents validation of new analytical expressions for the turbulent burning velocity, S-T, based on asymptotic behavior at the leading edge (LE) in turbulent premixed combustion. Reaction and density variation are assumed to be negligible at the LE to avoid the cold boundary difficulty in the statistically steady state. Good agreement is shown for the slopes, dS(T)/du', with respect to L-c/delta(f) at low turbulence, with both normalized by those of the reference cases. delta(f) is the inverse of the maximum gradient of reaction progress variable through an unstretched laminar flame, and L-c is the characteristic length scale given as burner diameter or measured integral length scale. Comparison is made for thirty-five datasets involving different fuels, equivalence ratios, H-2 fractions in fuel, pressures, and integral length scales from eight references [R. C. Aldredge et al., "Premixed-flame propagation in turbulent Taylor-Couette flow," Combust. Flame 115, 395 (1998); M. Lawes et al., " The turbulent burning velocity of iso-octane/air mixtures," Combust. Flame 159, 1949 (2012); H. Kido et al., " Influence of local flame displacement velocity on turbulent burning velocity," Proc. Combust. Inst. 29, 1855 (2002); J. Wang et al., " Correlation of turbulent burning velocity for syngas/air mixtures at high pressure up to 1.0 MPa," Exp. Therm. Fluid Sci. 50, 90 (2013); H. Kobayashi et al., " Experimental study on general correlation of turbulent burning velocity at high pressure," Proc. Combust. Inst. 27, 941 (1998); C. W. Chiu et al., " High-pressure hydrogen/carbon monoxide syngas turbulent burning velocities measured at constant turbulent Reynolds numbers," Int. J. Hydrogen Energy 37, 10935 (2012); P. Venkateswaran et al., " Pressure and fuel effects on turbulent consumption speeds of H-2/CO blends," Proc. Combust. Inst. 34, 1527 (2013); M. Fairweather et al., " Turbulent burning rates of methane and methane-hydrogen mixtures," Combust. Flame 156, 780 (2009)]. The turbulent burning velocity is shown to increase as the flamelet thickness, delta(f), decreases at a high pressure, for an equivalence ratio slightly rich or close to stoichiometric and for mixture of a high H2 fraction. Two constants involved are C to scale turbulent diffusivity as a product of turbulent intensity and characteristic length scale and C-s to relate delta(f) with the mean effective L-m.L-m = (D-mu/S-Lu(0)) is the scale of exponential decay at the LE of an unstretched laminar flame. The combined constant, KC/C-s, is adjusted to match measured turbulent burning velocities at low turbulence in each of the eight different experimental setups. All measured S-T/S-Lu(0) values follow the line, KDtu/D-mu + 1, at low turbulent intensities and show bending below the line due to positive mean curvature and broadened flamelet thickness at high turbulent intensities. Further work is required to determine the constants, C-s and K, and the factor, L-m/L*(m)-L-m (f)), that is responsible for bending in different conditions of laminar flamelet and incoming turbulence. (C) 2014 AIP Publishing LLC.open1123sciescopu

Bounded Model Checking of PLC ST Programs using Rewriting Modulo SMT

A programmable logic controller (PLC) is widely used in industrial control systems, and Structured text (ST) is an imperative language to develop PLC programs. Because of its safety-critical nature, formally analyzing PLC programs is important, and a rewriting-based formal semantics of ST has been proposed for this purpose. This paper presents a bounded model checking technique for PLC ST programs based on the rewriting-based semantics. We apply rewriting modulo SMT to symbolically analyze LTL properties of ST programs with respect to sequences of (possibly infinite) inputs and outputs. We have demonstrated the effectiveness of our approach using a traffic light case study.1

Emotion Evaluator: Expanding the Affective Lexicon with Neural Network Model

Measuring the emotion in words is valuable in that it analyzes emotions through language. However, it is difficult to find such measurements in low-resource languages. In this paper, we proposed a method to expand the affective lexicon by utilizing the context of words. The proposed model predicted the Valence and Arousal values of words using their dictionary definitions. In Study 1, we reviewed previous studies about the Korean affective lexicon and integrated data from these studies. The model was trained to minimize the MSE error between the Valence and Arousal values of the words and their predictions. We then checked the distribution of Valence and Arousal values of Korean vocabulary by applying our model to the Korean dictionary. In Study 2, a new affective lexicon was built to empirically validate our model. We found a negatively biased error pattern on model predictions and discussed why it happened

Reproducible Construction of Surface Tension-Mediated Honeycomb Concave Microwell Arrays for Engineering of 3D Microtissues with Minimal Cell Loss

<div><p>The creation of engineered 3D microtissues has attracted prodigious interest because of the fact that this microtissue structure is able to mimic in vivo environments. Such microtissues can be applied extensively in the fields of regenerative medicine and tissue engineering, as well as in drug and toxicity screening. Here, we develop a novel method of fabricating a large number of dense honeycomb concave microwells via surface tension-mediated self-construction. More specifically, in order to control the curvature and shape of the concavity in a precise and reproducible manner, a custom-made jig system was designed and fabricated. By applying a pre-set force using the jig system, the shape of the honeycomb concave well was precisely and uniformly controlled, despite the fact that wells were densely packed. The thin wall between the honeycomb wells enables the minimization of cell loss during the cell-seeding process. To evaluate the performance of the honeycomb microwell array, rat hepatocytes were seeded, and spheroids were successfully formed with uniform shape and size. Liver-specific functions such as albumin secretion and cytochrome P450 were subsequently analyzed. The proposed method of fabricating honeycomb concave wells is cost-effective, simple, and reproducible. The honeycomb well array can produce multiple spheroids with minimal cell loss, and can lead to significant contributions in tissue engineering and organ regeneration.</p></div

CPI 보안 강화 코드 변환의 실용적인 동등성 검사 기법

코드 변환 시의 동등성이 만족되지 않을 경우 소프트웨어 오류를 야기할 수 있다. 기존의 정리 증명을 통한 코드 변환의 동등성 검사는 코드의 규모가 커질수록 기하급수적으로 높은 비용이 요구되기 때문에 실제 소프트웨어 개발 시에 적용하기 어렵다. 본 논문에서는 규칙 증명과 코드 검사의 분리를 통하여 실용적인 LLVM의 코드 변환의 동등성 검사 기법을 제안한다. 먼저 주어진 코드 변환 규칙의 동등성은 자동정리증명을 통하여 컴파일 전에 별도로 증명한다. 그리고 컴파일 과정에서 변환 전과 후의 코드에 대한 정적 분석을 수행하여 코드 변환 규칙이 생성된 코드에 올바르게 적용되었는지 검사한다. 이러한 코드 분석의 수행 시간은 코드의 규모에 선형으로 증가하기 때문에, 규모가 큰 코드에도 효과적으로 적용될 수 있다. 제안된 연구를 코드 포인터 무결성(code pointer integrity) 보안강화 코드변환에 적용하여 LLVM 기반 도구제작에 활용하였다. Code transformation is widely used to improve the performance and security of programs, but serious software errors can occur in this process if the generated program is not equivalent to the original program. There are a number of approaches for translation validation that can be used to prove the equivalence of programs, but the high cost of proof checking restricts the applicability of these techniques for large programs. In this paper, we propose a practical approach for checking the correctness of LLVM code transformation. We first prove the correctness of the transformation rules using automated theorem proving before compilation. We then perform a simple code analysis method—as opposed to directly proving the program equivalence— to check whether the transformations rules are correctly applied to the generated code. As the complexity of the proposed code analysis is linear, our technique can be effectively applied to large programs, unlike previous techniques. To prove the effectiveness of the proposed approach, we present a case study on LLVM code transformation for a code pointer integrity instrumentation.22Nkc

Cross-sectional scanning electron microscopy (SEM) images of honeycomb concave microwell.

<p>Curvatures of honeycomb concave microwells formed by applying various forces to the PDMS prepolymer. The black dotted lines and black triangles show the original microwell before pouring the PDMS prepolymer. The blue-dotted circle depicts the radius of the honeycomb concave microwell. Scale bars: 200 μm.</p

Hepatocyte spheroids in honeycomb concave microwells exhibit greater liver-specific function than those in circular concave microwells.

<p>(a) Analysis of metabolic functions of spheroids in the two types of microwells, as measured by the secretion of albumin. (b) Immunostaining of hepatocyte spheroids for albumin (primary hepatocytes; green in first row), DAPI (nuclei; blue), cytochrome P450 activity (CYP450; green in second row) and microfilaments (F-actin; red). (c) Quantified analysis of hepatocytes function test. Scale bars: 300 μm.</p