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41.
Aryal R Baral B Vigneswaran S Naidu R Loganathan P 《Water science and technology》2011,63(10):2238-2243
Road dust is one of the major threats to the urban environment due to wash-off of dust to the surrounding catchments during wet weather period. The dust contains wide range of toxic contaminants such as heavy metals, polycyclic aromatic hydrocarbons (PAHS) and endocrine disrupting chemicals. Among the toxic contaminants, PAHs are of environmental concern due to their potential carcinogenic and mutagenic effect besides endocrine disruptive behaviour. Eighteen road dust samples from Sydney were collected in different time periods for a year and analysed for 16 US EPA PAHS. Total PAHs content range in the dust was 9-105 pg/g. Total and individual PAH contents were highest in the finest size fraction (<75 microm) and in winter compared to the other seasons. The PAH profiles in the different particle sizes were similar but different between the four seasons. The concentrations of higher molecular weight PAHS (4- and 5-rings) were much greater than the concentrations of lower molecular weight PAHs (2- and 3-rings). Toxicity equivalency factor application showed that the longer the dry weather period the higher the total PAHs content and toxicity in the dust. 相似文献
42.
Jörg Hakenberg Illés Solt Domonkos Tikk Võ Há Nguyên Luis Tari Quang Long Nguyen Chitta Baral Ulf Leser 《Computational Intelligence》2011,27(4):665-680
The BioNLP’09 Shared Task deals with extracting information on molecular events, such as gene expression and protein localization, from natural language text. Information in this benchmark are given as tuples including protein names, trigger terms for each event, and possible other participants such as bindings sites. We address all three tasks of BioNLP’09: event detection, event enrichment, and recognition of negation and speculation. Our method for the first two tasks is based on a deep parser; we store the parse tree of each sentence in a relational database scheme. From the training data, we collect the dependencies connecting any two relevant terms of a known tuple, that is, the shortest paths linking these two constituents. We encode all such linkages in a query language to retrieve similar linkages from unseen text. For the third task, we rely on a hierarchy of hand‐crafted regular expressions to recognize speculation and negated events. In this paper, we added extensions regarding a post‐processing step that handles ambiguous event trigger terms, as well as an extension of the query language to relax linkage constraints. On the BioNLP Shared Task test data, we achieve an overall F1‐measure of 32%, 29%, and 30% for the successive Tasks 1, 2, and 3, respectively. 相似文献
43.
The Gelfond-Lifschitz operator associated with a logic program (and likewise the operator associated with default theories by Reiter) exhibits oscillating behavior. In the case of logic programs, there is always at least one finite, nonempty collection of Herbrand interpretations around which the Gelfond-Lifschitz operator bounces around. The same phenomenon occurs with default logic when Reiter's operator is considered. Based on this, a stable class semantics and extension class semantics has been proposed. The main advantage of this semantics was that it was defined for all logic programs (and default theories), and that this definition was modelled using the standard operators existing in the literature such as Reiter's operator. In this paper our primary aim is to prove that there is a very interestingduality between stable class theory and the well-founded semantics for logic programming. In the stable class semantics, classes that were minimal with respect to Smyth's power-domain ordering were selected. We show that the well-founded semantics precisely corresponds to a class that is minimal w.r.t. Hoare's power domain ordering: the well-known dual of Smyth's ordering. Besides this elegant duality, this immediately suggests how to define a well-founded semantics for default logic in such a way that the dualities that hold for logic programming continue to hold for default theories. We show how the same technique may be applied to strong autoepistemic logic: the logic of strong expansions proposed by Marek and Truszczynski. 相似文献
44.
Conceptual Modeling and Querying in Multimedia Databases 总被引:1,自引:0,他引:1
In this paper, we discuss some design principles that will aid in the design and querying of multimedia databases. We use an object-relational data model and argue that multimedia objects should normally have a special attribute called core which stores the real object itself in contrast to the abstraction which is reflected in the rest of the attributes. We present an extension to the ER Diagram that takes advantage of the core notion to facilitate design of multimedia databases. We discuss some desirable features in a query language for multimedia databases: simplifications like the use of path expressions and implicit use of functions (methods) as attributes, and explicit specification of the display layout and format either at the data definition level or query specification level. To materialize this last feature, we propose a display specification extension to SQL (SQL+D) that we have implemented. 相似文献
45.
Choi DS Park J Kim S Gracias DH Cho MK Kim YK Fung A Lee SE Chen Y Khanal S Baral S Kim JH 《Journal of nanoscience and nanotechnology》2008,8(5):2323-2327
We describe a method to induce hyperthermia in cells, in-vitro, by remotely heating Ni nanowires (NWs) with radio frequency (RF) electromagnetic fields. Ni NWs were internalized by human embryonic kidney cells (HEK-293). Only cells proximal to NWs or with internalized NWs changed shape on exposure to RF fields indicative of cell death. The cell death occurs as a result of hyperthermia, since the RF field remotely heats the NWs as a result of magnetic hysteresis. This is the first demonstration of hyperthermia induced by NWs; since the NWs have anisotropic and strong magnetic moments, our experiments suggest the possibility of performing hyperthermia at lower field strengths in order to minimize damage to untargeted cells in applications such as the treatment of cancer. 相似文献
46.
Khagendra Thapa 《电子产品世界》2007,(8):123-125
序言 随着便携式手持设备(如手机、PDA等)的功能不断增加,加上对较小体积与更长电池寿命的要求,使得锂电池成为许多此类设备的首选供电能源.本文将讨论线性充电技术与相关的离散调节元件,并重点讨论主要离散参数与选择标准. 相似文献
47.
This paper summarizes functions and features of a new latch design, named as pawl latch from herein, for implementation on ramp loading disk drives, where a disk drive with a ramp would allow actuator to stay on the ramp outside the disk when not in use. The new latch system consists of two latch mechanisms: one is inertia latch and the other is magnetic latch. These two latches work together to obtain very reliable non-contact break free latch while maintaining high resistance during rotary shock condition. Simple control method is also presented to alleviate audible noise issue generated using the pawl latch mechanism. 相似文献
48.
Baral Samit Alsadoon Abeer Prasad P. W. C. Al Aloussi Sarmad Alsadoon Omar Hisham 《Multimedia Tools and Applications》2021,80(21-23):32639-32664
Multimedia Tools and Applications - Cardiac arrest is a common issue in Intensive Care Units (ICU) with low survival rate. Deep learning algorithms have been used to predict cardiac arrest... 相似文献
49.
Silica-water interaction plays an essential role for the mechanical strength and chemical durability of alkali-doped-silicate glasses. A comprehensive study of single and mixed alkali-silicate glasses with 30% molar content of Li2O, Na2O, and K2O, and half-half mixture of Li2O–Na2O, Li2O–K2O, and Na2O–K2O in hydrated models is carried out using density functional theory methods. Information on atomic geometry, electronic structure, interatomic bonding, partial charge distribution, mechanical, and optical properties are obtained and compared. It confirms that water in the solvated and confined bulk models can be either dissociated or remains as H2O molecule depending on the distribution and specific alkali elements. A quantum mechanical metric, the total bond order density is used to unravel the atomistic origin of the internal cohesion and strength of glasses in different environments. In particular, we show that the mechanical strength of bulk alkali-silicate glasses is enhanced by hydration with some evidence that mixing of alkali ions tends to degrade the strength of the hydrated glasses. These results are discussed in the context of experimental observations and a few existing simulations using classical molecular dynamics. 相似文献
50.
Grain Boundary Space Charge Effect and Proton Dynamics in Chemically Stable Perovskite‐Type Ba0.5Sr0.5Ce0.6Zr0.2Gd0.1Y0.1O3−δ (BSCZGY): A Case Study on Effect of Sintering Temperature
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Kalpana Singh Ashok Kumar Baral Venkataraman Thangadurai 《Journal of the American Ceramic Society》2016,99(3):866-875
The present study reports the effect of sintering temperature on the proton dynamics of perovskite‐type Ba0.5Sr0.5Ce0.6Zr0.2Gd0.1Y0.1O3?δ (BSCZGY) by establishing a co‐relation between the grain‐boundary (GB) space charge effect, electrical conductivity and dielectric loss of the BSCZGY samples sintered at 1300°C, 1400°C, and 1550°C for 20 h in air. Although, the GBs are the main source of resistance in BaZrO3 based ceramic proton conductors, we show that the GB impedance disappeared above 450°C and 300°C, respectively, for BSCZGY samples sintered at 1300°C and 1400°C. Interestingly, the BSCZGY sample sintered at 1550°C showed absence of GB contribution to total conductivity even at 200°C. The GB electrostatic potential [?(0)] was found to vary between 0.35–0.38 V and 0.4–0.45 V, respectively, for the samples sintered at 1300°C and 1400°C at 200°C–300°C. The migration energy (Em) of the protons was found to be 0.71, 0.65 and 0.58 eV for the sample sintered at 1300°C, 1400°C and 1550°C, respectively. 相似文献