2,626 research outputs found

    Do Universities Have a Role in Managing Public Schools: Lessons from the Penn Partnership Schools

    Get PDF
    Over the past several years, the standards based reform movement has produced increasingly dramatic shifts in the relationship between educational policies and school-based practices. The No Child Left Behind Act of 2001 has further intensified public scrutiny and local accountability for demonstrating that all children meet national standards in their learning. However, to achieve desired improvements in student learning, it is clear that many schools must fundamentally rethink the ways in which they organize instructional practices

    ChOiRe: Characterizing and Predicting Human Opinions with Chain of Opinion Reasoning

    Full text link
    Aligning language models (LMs) with human opinion is challenging yet vital to enhance their grasp of human values, preferences, and beliefs. We present ChOiRe, a four-step solution framework to predict human opinion that differentiates between the user explicit personae (i.e. demographic or ideological attributes) that are manually declared and implicit personae inferred from user historical opinions. Specifically, it consists of (i) an LM analyzing the user explicit personae to filter out irrelevant attributes; (ii) the LM ranking the implicit persona opinions into a preferential list; (iii) Chain-of-Opinion (CoO) reasoning, where the LM sequentially analyzes the explicit personae and the most relevant implicit personae to perform opinion prediction; (iv) and where ChOiRe executes Step (iii) CoO multiple times with increasingly larger lists of implicit personae to overcome insufficient personae information to infer a final result. ChOiRe achieves new state-of-the-art effectiveness with limited inference calls, improving previous LLM-based techniques significantly by 3.22%.Comment: 17 page

    Radiation-Pressure-Mediated Control of an Optomechanical Cavity

    Get PDF
    We describe and demonstrate a method to control a detuned movable-mirror Fabry-Perot cavity using radiation pressure in the presence of a strong optical spring. At frequencies below the optical spring resonance, self-locking of the cavity is achieved intrinsically by the optomechanical (OM) interaction between the cavity field and the movable end mirror. The OM interaction results in a high rigidity and reduced susceptibility of the mirror to external forces. However, due to a finite delay time in the cavity, this enhanced rigidity is accompanied by an anti-damping force, which destabilizes the cavity. The cavity is stabilized by applying external feedback in a frequency band around the optical spring resonance. The error signal is sensed in the amplitude quadrature of the transmitted beam with a photodetector. An amplitude modulator in the input path to the cavity modulates the light intensity to provide the stabilizing radiation pressure force

    Quantum spin Hall phase in neutral zigzag graphene ribbons

    Full text link
    We present a detailed description of the nature of the wavefunction and spin distribution of the zero energy modes of zigzag graphene ribbons (ZGRs) in the presence of the intrinsic spin_orbit (I-SO) interaction. These states characterize the quantum spin Hall (QSH) phase in graphene ribbons. We provide analytic expressions for wavefunctions and show how these evolve as the strength of the interaction and the ribbon width are changed. For odd-width ribbons, we show that its insulating nature precludes the existence of a QSH phase. For these systems the I-SO interaction is predicted to have a stronger effect as shown by the enhancement of the gap as the interaction strength is turned on

    CoAnnotating: Uncertainty-Guided Work Allocation between Human and Large Language Models for Data Annotation

    Full text link
    Annotated data plays a critical role in Natural Language Processing (NLP) in training models and evaluating their performance. Given recent developments in Large Language Models (LLMs), models such as ChatGPT demonstrate zero-shot capability on many text-annotation tasks, comparable with or even exceeding human annotators. Such LLMs can serve as alternatives for manual annotation, due to lower costs and higher scalability. However, limited work has leveraged LLMs as complementary annotators, nor explored how annotation work is best allocated among humans and LLMs to achieve both quality and cost objectives. We propose CoAnnotating, a novel paradigm for Human-LLM co-annotation of unstructured texts at scale. Under this framework, we utilize uncertainty to estimate LLMs' annotation capability. Our empirical study shows CoAnnotating to be an effective means to allocate work from results on different datasets, with up to 21% performance improvement over random baseline. For code implementation, see https://github.com/SALT-NLP/CoAnnotating

    The prevalence of ocular diseases in primary and junior high school students on Orchid Island

    Get PDF
    AbstractObjectiveTo assess the prevalence of refractive error and ocular diseases in primary and junior high school students on Orchid Island.Materials and MethodsThis is a cross-sectional study of all students in the primary and junior high schools on Orchid Island conducted within 1 week in 2008. Each student received a visual acuity examination without correction with the Landolt-C chart. An experienced ophthalmologist performed associated assessments through retinoscopy, slit lamp, and fundoscopy.ResultsOf the 403 student residents, 260 were primary school students (139 boys and 121 girls) and 143 were junior high school students (74 boys and 69 girls). Visual acuity in two eyes was < 0.1, in 14 eyes was between 0.1 and 0.3, in 34 eyes was between 0.4 and 0.7, in 225 eyes was between 0.8 and 1.0, and in 531 eyes was between 1.2 and 2.0. Myopia was found in 21 students (21/403, 5.21%; 9 primary school students and 12 junior high school students). Four students (4/403, 0.99%) had amblyopia, of whom two had anisometropia (unilateral high hyperopia), one had high astigmatism in both eyes, and the other had unilateral esotropia. Lens dislocation was found in one student (0.25%) with Marfan syndrome. Retinal vasculitis and optic atrophy were found in one student (0.25%) with systemic lupus erythematosus.ConclusionBecause it is a small, isolated island, Orchid Island still has a unique traditional culture and life style. Therefore the prevalence of myopia in primary school and junior high school students on Orchid Island is low, and 94% of all the students had uncorrected visual acuity above 0.8

    Post-heat treatment of electrochemically carburized low-carbon steel

    Get PDF
    Limited studies are available on post-heat treatment (tempering/annealing) of electro­chemically carburized low-carbon steel, which can relieve internal stresses induced by the quenching process. In this study, the electrochemical carburization was carried out using the electrolyte mixture of sodium carbonate (Na2CO3) and sodium chloride (NaCl) under a CO2 gas environment and 800 °C. The samples were then quenched in either water or oil. The peak hardness of the water-quenched sample (WQ) was higher than the oil-quenched sample (OQ). Comparatively, post-heat treated (tempered and annealed) samples showed lower peak hardness compared to quenched samples. An optical microscope was used to observe microstructural changes, while X-ray diffraction (XRD) was used to examine metal phases within all samples. The full width at half maximum (FWHM) of the martensite peak supported the stress relief in both tempered and annealed samples. Scanning electron microscope (SEM) with energy dispersive X-ray (EDX) was applied to determine the elemental composition of as received and electrochemically carburized and quenched low-carbon steel samples. The carbon content of the WQ sample was relatively higher than the OQ sample, whereas the tempered samples showed higher carbon content compared to the annealed samples, but both were lower than for quenched samples. Electrochemical carburization increased the carbon content and improved the hardness, while the tempering or annealing process relieved internal stresses that resulted in the hardness reduction

    Do novel genotypes drive the success of an invasive bark beetle–fungus complex? Implications for potential reinvasion

    Get PDF
    Novel genotypes often arise during biological invasions, but their role in invasion success has rarely been elucidated. Here we examined the population genetics and behavior of the fungus, Leptographium procerum, vectored by a highly invasive bark beetle, Dendroctonus valens, to determine whether genetic changes in the fungus contributed to the invasive success of the beetle–fungal complex in China. The fungus was introduced by the beetle from the United States to China, where we identified several novel genotypes using microsatellite markers. These novel genotypes were more pathogenic to Chinese host seedlings than were other genotypes and they also induced the release of higher amounts of 3-carene, the primary host attractant for the beetle vector, from inoculated seedlings. This evidence suggests a possible mechanism, based on the evolution of a novel genotype during the two or three decades since its introduction, for the success of the beetle–fungal complex in its introduced region.This work was funded by the National Natural Science Foundation of China (30921063), the CAS Knowledge Innovation Key Research Program (KSCX2-EW-J-2), TPCP (Tree Protection Co-operation Programme), and a grant from the USDA Forest Service, Western Wildlands Environmental Threats Assessment Center (Prineville, Oregon, USA).http://www.esajournals.org/loi/ecol
    • …
    corecore