45 research outputs found

    The Application of Magnetic Guidance Drilling Technology in Shengli Oilfield

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    The magnetic guidance drilling technology could use the magnetic guidance instrument to measure the distance between the signal source and the instrument, which is used to control the well trajectory. It is an essential supplement of the existing steering drilling technology. At present, the magnetic guidance drilling technology is mainly applied to dual horizontal wellslls for heavy oil reservoir, CBM horizontal connected wells, wells to mine underground soluble minerals, and relief wells. This paper mainly introduces the working process of magnetic guidance drilling technology and connected wells. In order to test the overall performance of this technology, an experimental study is conducted on it, and the field test was carried on Shengli oil field

    Progressively Dual Prior Guided Few-shot Semantic Segmentation

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    Few-shot semantic segmentation task aims at performing segmentation in query images with a few annotated support samples. Currently, few-shot segmentation methods mainly focus on leveraging foreground information without fully utilizing the rich background information, which could result in wrong activation of foreground-like background regions with the inadaptability to dramatic scene changes of support-query image pairs. Meanwhile, the lack of detail mining mechanism could cause coarse parsing results without some semantic components or edge areas since prototypes have limited ability to cope with large object appearance variance. To tackle these problems, we propose a progressively dual prior guided few-shot semantic segmentation network. Specifically, a dual prior mask generation (DPMG) module is firstly designed to suppress the wrong activation in foreground-background comparison manner by regarding background as assisted refinement information. With dual prior masks refining the location of foreground area, we further propose a progressive semantic detail enrichment (PSDE) module which forces the parsing model to capture the hidden semantic details by iteratively erasing the high-confidence foreground region and activating details in the rest region with a hierarchical structure. The collaboration of DPMG and PSDE formulates a novel few-shot segmentation network that can be learned in an end-to-end manner. Comprehensive experiments on PASCAL-5i and MS COCO powerfully demonstrate that our proposed algorithm achieves the great performance

    Determination of key enzymes for threonine synthesis through in vitro metabolic pathway analysis

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    Figure S1. The pathway flux (J) in the in vitro system when one enzyme concentration was increased. (A) The pathway flux when purified ThrA was added to the crude enzyme extract. (B) The pathway flux when purified Asd was added to the crude enzyme extract. (C) The pathway flux when purified ThrB was added to the crude enzyme extract. (D) The pathway flux when purified ThrC was added to the crude enzyme extract

    Surface modification of NiCo2Te4 nanoclusters: a highly efficient electrocatalyst for overall water-splitting in neutral solution

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    In this paper, we for the first time report the catalytic activity and durability of nickel cobaltite telluride (NiCo2Te4) nanocluster bifunctional catalysts can be significantly boosted by surface modification with perylene-tetracarboxylic-dianhydride for overall water-splitting in neutral solution. We reveal that tuning energy distribution of nanoclusters via a simple surface ligand can drastically increase the catalytic activity towards efficient hydrogen and oxygen evolution reaction simultaneously. A two-electrode based water electrolysis cell using this newly developed nanocluster catalyst operates at a low bias voltage of 1.55 V to achieve a current density of 10 mA路cm-2 in near-neutral pH solution for overall water-splitting. This, to the best of our knowledge, represents the most efficient mixed-transition-metal-based electrode that has so far been reported for electrochemical water splitting

    Eficacia de la magnetoter谩pia en la consolidaci贸n de fracturas 贸seas. Revisi贸n sistem谩tica.

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    El trabajo de fin de grado realizado consiste en una revisi贸n sistem谩tica, tratando de al eficacia del aparato de magnetoterapia en relaci贸n a la consolidaci贸n 贸sea cualidad y tiempo. Para ello se utilizaron las bases de datos PubMed, ENFISPO, PEDro, la Biblioteca Cochrane de estudios publicados entre el periodo de a帽o 2010 y 2015. Los resultados en relaci贸n a la consolidaci贸n 贸sea, ninguno de los tres art铆culos seleccionados obtuvimos resultados significativos. Aunque las pruebas de laboratorios disponibles indican que la estimulaci贸n con campos electromagn茅ticos puede ofrecer alg煤n beneficio en la consolidaci贸n de fracturas 贸seas, a la hora de aplicarlo en seres humanos como posible tratamiento no es concluyente o suficiente para informar de su utilizaci贸n en la pr谩ctica actual. Las conclusiones y resultados m谩s definitivos o positivos, recomendando su utilizaci贸n sobre el efecto en el tratamiento aguardan ensayos controlados aleatorios adicionales bien realizados

    Oroxylin a Inhibits the Protection of Bone Marrow Microenvironment on CML Cells Through CXCL12/CXCR4/P-gp Signaling Pathway

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    Imatinib (IM) resistance could have significant impact on the survival time of the CML-patients treated with IM. Previous studies have shown that the protective effects of the bone marrow stroma cells (BMSCs) on CML cells are achieved by the secretion of CXCL12. The aim of this study was to investigate whether Oroxylin A could reverse the protective effect of BMSCs on CML cells and illuminate the underlying mechanisms. The results showed that CXCL12 could enhance the resistance potential of K562 and KU812 cells to IM by increasing the expression of CXCR4, thus promoting the translocation of 尾-catenin into nucleus and subsequently increasing the expression of P-gp in K562 and KU812 cells. What's more, IM resistance could also be partially reversed by CXCR4 siRNA transfection. Moreover, the reverse effect of IM resistance by Oroxylin A was demonstrated by the inhibition of 尾-catenin/P-gp pathway via the decrease of CXCR4 in vitro. The in vivo study also showed that Oroxylin A could decrease the expression of P-gp and 尾-catenin in mice bone marrow with low toxicity, which could be consistent with the mechanisms verified in vitro studies. In conclusion, all these results showed that Oroxylin A improved the sensitivity of K562 and KU812 cells to IM in BM microenvironment by decreasing the expression of CXCR4 and then inhibiting 尾-catenin/P-gp pathway

    Februus: Input Purification Defense Against Trojan Attacks on Deep Neural Network Systems

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    We propose Februus; a new idea to neutralize highly potent and insidious Trojan attacks on Deep Neural Network (DNN) systems at run-time. In Trojan attacks, an adversary activates a backdoor crafted in a deep neural network model using a secret trigger, a Trojan, applied to any input to alter the model's decision to a target prediction---a target determined by and only known to the attacker. Februus sanitizes the incoming input by surgically removing the potential trigger artifacts and restoring the input for the classification task. Februus enables effective Trojan mitigation by sanitizing inputs with no loss of performance for sanitized inputs, Trojaned or benign. Our extensive evaluations on multiple infected models based on four popular datasets across three contrasting vision applications and trigger types demonstrate the high efficacy of Februus. We dramatically reduced attack success rates from 100% to near 0% for all cases (achieving 0% on multiple cases) and evaluated the generalizability of Februus to defend against complex adaptive attacks; notably, we realized the first defense against the advanced partial Trojan attack. To the best of our knowledge, Februus is the first backdoor defense method for operation at run-time capable of sanitizing Trojaned inputs without requiring anomaly detection methods, model retraining or costly labeled data.Comment: 16 pages, to appear in the 36th Annual Computer Security Applications Conference (ACSAC 2020

    Tubeless video-assisted thoracic surgery for pulmonary ground-glass nodules: expert consensus and protocol (Guangzhou)

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