110 research outputs found

    Barriers and bridges for intensified wood production in Russia: Insights from the environmental history of a regional logging frontier

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    Russia sees the need to increase wood production. The aim of this paper is to contribute to the understanding of barriers and bridges in social and ecological systems for intensification of wood production in NW Russia. This requires that past development trajectories are understood. Using a local logging frontier in Russia's Komi Republic as a case study, we employed an environmental history approach to: (1) recreate the wood harvesting history for the period 1719-2014, (2) identify the main actors that produced this history, and (3) analyse what ideologies influenced decision making. First, after a long history of selective harvesting before the Russian Revolution in 1917, forests were rapidly clear-felled during the Soviet period 1921-1991. Following general economic deceleration, and thus severely reduced harvesting activities during 1992-1997, the rate of logging has increased slightly again. To conclude, barriers in ecosystems to intensification include Soviet legacies of large-scale harvesting, which resulted in a very uneven age distribution, limited and poorly conducted silviculture, as well as insufficient transport infrastructure. Additionally, social system barriers are a conservative mind-set at the policy level, unpredictable conditions for forest use rights and ownership, and limited value-added production at local level. Developing predictable rules and norms, forest zoning at local to regional scales, and the emergence of place-based multi-level collaborative learning concepts like Model Forest provide opportunity for bridging the observed barriers

    Modeling Ideological Salience and Framing in Polarized Online Groups with Graph Neural Networks and Structured Sparsity

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    The increasing polarization of online political discourse calls for computational tools that automatically detect and monitor ideological divides in social media. We introduce a minimally supervised method that leverages the network structure of online discussion forums, specifically Reddit, to detect polarized concepts. We model polarization along the dimensions of salience and framing, drawing upon insights from moral psychology. Our architecture combines graph neural networks with structured sparsity learning and results in representations for concepts and subreddits that capture temporal ideological dynamics such as right-wing and left-wing radicalization

    An Information-Theoretic Approach and Dataset for Probing Gender Stereotypes in Multilingual Masked Language Models

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    Bias research in NLP is a rapidly growing and developing field. Similar to CrowS-Pairs (Nangia et al., 2020), we assess gender bias in masked-language models (MLMs) by studying pairs of sentences with gender swapped person references. Most bias research focuses on and often is specific to English.Using a novel methodology for creating sentence pairs that is applicable across languages, we create, based on CrowS-Pairs, a multilingual dataset for English, Finnish, German, Indonesian and Thai.Additionally, we propose SJSD, a new bias measure based on Jensen–Shannon divergence, which we argue retains more information from the model output probabilities than other previously proposed bias measures for MLMs.Using multilingual MLMs, we find that SJSD diagnoses the same systematic biased behavior for non-English that previous studies have found for monolingual English pre-trained MLMs. SJSD outperforms the CrowS-Pairs measure, which struggles to find such biases for smaller non-English datasets

    Femtosecond and Ultraviolet Laser Irradiation of Graphite-Like Hexagonal Boron Nitride

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    Effect of the femtosecond and nanosecond UV laser irradiation (below the ablation threshold) of graphite-like hexagonal boron nitride (hBN) has been studied. Experiments were carried out with the compacted powder under high vacuum at room temperature using excimer KrF laser (248 nm). In the nanosecond operation mode, the laser-induced fluorescence spectra are found strongly modified depending on the integrated doze, which is attributed to a progressive enrichment of the surface layer by elemental boron. A slow sample recovery after the laser irradiation has been observed. On the other hand, in the femtosecond mode the fluorescence spectra depend on the laser fluence, and the changes are reversible: low energy fluorescence spectra are restored immediately when the laser energy decreases. This effect can be explained by a material bleaching, which favors a bulk centers emission. The ablation threshold has been determined as 78 mJ/cm2 in the femtosecond laser operational mode

    LMTurk: Few-Shot Learners as Crowdsourcing Workers in a Language-Model-as-a-Service Framework

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    Vast efforts have been devoted to creating high-performance few-shot learners, i.e., large-scale pretrained language models (PLMs) that perform well with little downstream task training data. Training PLMs has incurred significant cost, but utilizing the few-shot learners is still challenging due to their enormous size. This work focuses on a crucial question: How to make effective use of these few-shot learners? We propose LMTurk, a novel approach that treats few-shotlearners as crowdsourcing workers. The rationale is that crowdsourcing workers are in fact few-shot learners: They are shown a few illustrative examples to learn about a task and then start annotating. LMTurk employs few-shot learners built upon PLMs as workers. We show that the resulting annotations can be utilized to train models that solve the task well and are small enough to be deployable in practical scenarios. Active learning is integrated into LMTurk to reduce the amount of queries made to PLMs, minimizing the computational cost of running PLM inference passes. Altogether, LMTurk is an important step towards making effective use of current PLMs

    Deriving Global OH Abundance and Atmospheric Lifetimes for Long-Lived Gases: A Search for CH 3 CCl 3 Alternatives

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    An accurate estimate of global hydroxyl radical (OH) abundance is important for projections of air quality, climate, and stratospheric ozone recovery. As the atmospheric mixing ratios of methyl chloroform (CH₃CCl₃) (MCF), the commonly used OH reference gas, approaches zero, it is important to find alternative approaches to infer atmospheric OH abundance and variability. The lack of global bottom‐up emission inventories is the primary obstacle in choosing a MCF alternative. We illustrate that global emissions of long‐lived trace gases can be inferred from their observed mixing ratio differences between the Northern Hemisphere (NH) and Southern Hemisphere (SH), given realistic estimates of their NH‐SH exchange time, the emission partitioning between the two hemispheres, and the NH versus SH OH abundance ratio. Using the observed long‐term trend and emissions derived from the measured hemispheric gradient, the combination of HFC‐32 (CH₂F₂), HFC‐134a (CH₂FCF₃, HFC‐152a (CH₃CHF₂), and HCFC‐22 (CHClF₂), instead of a single gas, will be useful as a MCF alternative to infer global and hemispheric OH abundance and trace gas lifetimes. The primary assumption on which this multispecies approach relies is that the OH lifetimes can be estimated by scaling the thermal reaction rates of a reference gas at 272 K on global and hemispheric scales. Thus, the derived hemispheric and global OH estimates are forced to reconcile the observed trends and gradient for all four compounds simultaneously. However, currently, observations of these gases from the surface networks do not provide more accurate OH abundance estimate than that from MCF

    The dinoflagellate cyst genera Achomosphaera Evitt 1963 and Spiniferites Mantell 1850 in Pliocene to modern sediments: a summary of round table discussions

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    Source at https://doi.org/10.1080/01916122.2018.1465739. We present a summary of two round-table discussions held during two subsequent workshops in Montreal (Canada) on 16 April 2014 and Ostend (Belgium) on 8 July 2015. Five species of the genus Achomosphaera Evitt 1963 and 33 of the genus Spiniferites Mantell 1850 emend. Sarjeant 1970 occuring in Pliocene to modern sediments are listed and briefly described along with remarks made by workshop participants. In addition, several holotypes and topotypes are reillustrated. Three species previously assigned to Spiniferites are here considered/accepted as belonging to other genera: Impagidinium inaequalis (Wall and Dale in Wall et al.1973) Londeix et al. 2009, Spiniferites? rubinus (Rossignol 1962 ex Rossignol 1964) Sarjeant 1970, and Thalassiphora balcanica Baltes ̧ 1971. This summary forms the basis for a set of papers that follows, where points raised during the workshops are explored in greater detail

    HĂ„llbar landsbygdsutveckling

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    Landsbygdens naturresurser och andra vÀrden Àr viktiga för att vidareutveckla en biobaserad ekonomi och att stÀrka Sverige som besöksnation. DÀrför Àr det viktigt med befolkade, aktiva och vÀxande landsbygder. Landsbygden stÄr dock inför stora utmaningar. Hur skapas attraktiva bygder? Hur bevaras gamla jobb, och skapas nya? Hur bevaras ekologiska, sociala och kulturella vÀrden? Genom tvÀrvetenskaplig forskning tillsammans med aktörer pÄ olika samhÀllsnivÄer verkar vi för en hÄllbar landsbygd genom att generera kunskap och bidra till lÀrande. VÄrt internationella arbetssÀtt ger nya perspektiv pÄ kunskapsproduktion och lÀrande tillsammans med praktiker, och skapar förutsÀttningar för problembaserad utbildning för hÄllbar landsbygdsutveckling. HÀr presenteras huvudinriktningarna för vÄr forskning för hÄllbar landsbygdsutveckling

    High-resolution laser system for the S3-Low Energy Branch

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    In this paper we present the first high-resolution laser spectroscopy results obtained at the GISELE laser laboratory of the GANIL-SPIRAL2 facility, in preparation for the first experiments with the S3^3-Low Energy Branch. Studies of neutron-deficient radioactive isotopes of erbium and tin represent the first physics cases to be studied at S3^3. The measured isotope-shift and hyperfine structure data are presented for stable isotopes of these elements. The erbium isotopes were studied using the 4f126s24f^{12}6s^2 3H6→4f12(3H)6s6p^3H_6 \rightarrow 4f^{12}(^3 H)6s6p J=5J = 5 atomic transition (415 nm) and the tin isotopes were studied by the 5s25p2(3P0)→5s25p6s(3P1)5s^25p^2 (^3P_0) \rightarrow 5s^25p6s (^3P_1) atomic transition (286.4 nm), and are used as a benchmark of the laser setup. Additionally, the tin isotopes were studied by the 5s25p6s(3P1)→5s25p6p(3P2)5s^25p6s (^3P_1) \rightarrow 5s^25p6p (^3P_2) atomic transition (811.6 nm), for which new isotope-shift data was obtained and the corresponding field-shift F812F_{812} and mass-shift M812M_{812} factors are presented
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