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Existence and the Grounding of Metaphysics
Rafael Simián V.
Ideas y Valores , 2011,
Abstract: The article attempts to explain the connection between existence and the objective of the Critique of Pure Reason (the grounding of metaphysics). To that effect, it discusses some of the basic aspects of Kant’s understanding of human knowledge,as well as his conception of objective existence. The analysis carried out includes only that which may be established before (and is assumed by) the ranscendentalAesthetic and the Transcendental Analytic, showing that some of the most significant theses of Kant’s critique follow from these analyses.
Grounding Impedance Measurement of High Speed Railway Integrated Grounding System  [PDF]
Zhang Yi, Jianguo Wang, Yadong Fan, Mi Zhou, Li Cai
Journal of Power and Energy Engineering (JPEE) , 2015, DOI: 10.4236/jpee.2015.34027
Abstract:

The high-speed railway integrated grounding system is the basic guarantee for the safe and stable operation of the railway. It is the world’s largest long-distance horizontally elongated joint grounding system, which stretches the length of hundreds to thousands of kilometers, and its structure is not only different from power station and substation grounding system, but also different from the transmission line tower, lightning rod and other small grounding devices. There is little research information on the grounding impedance of high-speed railway integrated grounding system. This paper adopted 0.618 compensation method and reverse away method respectively, measured a section of high-speed railway integrated grounding system grounding impedance by JD16 and CA6425. Measurement results are in good agreement using those two type instrument. By using 0.618 compensation method, the measurement result will be gradually converged at 0.3 Ω with the increasing of current electrode distance, which is the real grounding impedance of integrated grounding system. By using reverse away method, the maximum measurement result difference is less than 0.024 Ω with the lead of current electrode distance increasing. The measurement results will be rapidly converged 0.25 Ω. The results showed that the reverse away method is helpful to shorten the length of current electrode wiring. The measurement error will be small when the current electrode wiring is longer.

The Research on Grounding Protection for 110kV Resistance Grounding Distribution System  [PDF]
Shan Sun, Guo Zeng, Xiaozang He, Yanping Lv, Xinyi Li
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.54B168
Abstract:

Using the neutral grounding method by the resistance in 110 kV system, it can limit the voltage sag and short circuit current when one-phase grounding fault occurred, but it will change the sequence of the network structure and parameters. This paper analyzes the size and distribution of zero sequence voltage and current when one-phase grounding fault occurred in the 110 kV resistance grounding system, and puts forward the grounding protection configuration setting principle of this system combining the power supplying characteristics of 110 kV distribution network. In a reforming substation as an example, the grounding protection of 110 kV lines and transformer have been set and calculated.

Lifted Unit Propagation for Effective Grounding  [PDF]
Pashootan Vaezipoor,David Mitchell,Maarten Mari?n
Computer Science , 2011,
Abstract: A grounding of a formula $\phi$ over a given finite domain is a ground formula which is equivalent to $\phi$ on that domain. Very effective propositional solvers have made grounding-based methods for problem solving increasingly important, however for realistic problem domains and instances, the size of groundings is often problematic. A key technique in ground (e.g., SAT) solvers is unit propagation, which often significantly reduces ground formula size even before search begins. We define a "lifted" version of unit propagation which may be carried out prior to grounding, and describe integration of the resulting technique into grounding algorithms. We describe an implementation of the method in a bottom-up grounder, and an experimental study of its performance.
Grounding of Textual Phrases in Images by Reconstruction  [PDF]
Anna Rohrbach,Marcus Rohrbach,Ronghang Hu,Trevor Darrell,Bernt Schiele
Computer Science , 2015,
Abstract: Grounding (i.e. localizing) arbitrary, free-form textual phrases in visual content is a challenging problem with many applications for human-computer interaction and image-text reference resolution. Although many data sources contain images which are described with sentences or phrases, they typically do not provide the spatial localization of the phrases. This is true for both curated datasets such as MSCOCO or large user generated content as e.g. in the YFCC 100M dataset. Consequently, being able to learn from this data without grounding supervision would allow large amount and variety of training data. For this setting we propose GroundeR, a novel approach, which is able to learn the grounding by aiming to reconstruct a given phrase using an attention mechanism. More specifically, during training time, the model encodes the phrase using an LSTM, and then has to learn to attend to the relevant image region in order to reconstruct the input phrase. At test time the correct attention, i.e. the grounding is evaluated. On the Flickr 30k Entities dataset our approach outperforms prior work which, in contrast to us, trains with the grounding (bounding box) annotations.
Study on the Influence of Grounding Conductor Structure on Its Grounding Impedance Spectrum Response  [PDF]
Xiaobin Cao, Wenyan Feng, Lin Yang, Yu Zhang
Energy and Power Engineering (EPE) , 2018, DOI: 10.4236/epe.2018.104B002
Abstract:
The grounding diagnosis of pole and tower plays an important role, and the tower is characterized by its unique characteristics. It is necessary to develop a new method for the diagnosis of pole and tower. Frequency diagnosis is applied in many aspects, so it is necessary to analyze the frequency response characteristics of pole and tower. The influence of the frequency response of pole and tower on the radius of the pole and the soil resistivity is analyzed under three different grounding structures using CDEGS software, and the differences and similarities of spectral response under different structures are discussed.
Grounding Systems for Power Supply Facilities  [PDF]
Vladimir Anatolevich Konusarov, Evgeniy Alekseevich Shutov, Tatyana Evgenievna Turukina
Energy and Power Engineering (EPE) , 2019, DOI: 10.4236/epe.2019.111001
Abstract: The goal of this work is creation of optimal grounding model at the substation 10/0.4 kV of the urban power distribution network. The electric current can pose a major threat to the man’s life and health. In addition to pose a threat for health, the rise of the short circuit, as a consequence of insulation faults, poses a threat to retirement of electric systems and fire risks. The reliable grounding system design has significant implications for protection of human being as well as for electrical facility protection. The set objective was performed on the base of analytical and software-based methods. Analytical method gives a qualitative indication at each step in analysis. It also allows evaluating the values effect on the result, but the method is not susceptible of tolerable accuracy, that is why analytical method serves as initial approximation in differentiating. Specified estimation can be performed in such software package as MATLAB or ETAP. Software-based estimation is based on the finite element method (FEM), the main advantage of which is the ability to create different forms of grounding and allows obtaining distribution graphs of the step potential on the earth’s surface and touch potential. The calculation results in comparison of analytical and software-based methods taking into account the grounding optimization. There are conclusions on the most effective ground network.
Optimal Programs to Reduce the Resistance of Grounding Systems
Run Xiong;Bin Chen;Cheng Gao;Yan-Xin Li;Wen Yang
PIER , 2013,
Abstract: In this paper, some optimal programs have been proposed through the analyses of transient grounding resistance (TGR) to reduce the grounding resistance using the finite-difference time-domain method. First, the TGR of various electrode types, lengths and sectional programs is studied, and it is found that a flat bar is the most financially efficient conductor to be used as grounding electrode. Enlarging grounding electrode length can reduce grounding resistance when it is shorter than the effective length, but the reduction effect declines as the length increases. Additionally, a series of small electrodes would lead to a much lower resistance than a single large one. Second, it is demonstrated that locally improving the soil near the grounding system is an efficient way of reducing the grounding resistance. Improving a limited area soil surrounding the lifting line would reduce the peak resistance significantly, while local enlarging electrodes surrounded soil conductivity can reduce the grounding system steady resistance obviously.
内外源提示下学障儿童注意定向的眼动研究  [PDF]
吴燕,隋光远
心里发展与教育 , 2006,
Abstract: 对三、六年级22名学障儿童和22名按年龄、性别和受教育水平匹配的正常儿童在内外源提示下的注意表现进行了眼动研究。结果表明:当内源性提示有效性比例较低时,学障和正常儿童的提示效度效应均不明显;当提示目标间隔时间较长时,外源性提示有效性对各组被试的反应时无显著影响;在内外源性提示下,六年级儿童的绩效好于三年级;学障儿童在反应时间、加工速度上和正常儿童没有显著差异,但在加工广度和策略上不如正常儿童。这些结果表明学障儿童的注意定向和相关的认知加工能力与正常儿童有所差异。
The stability of grounding lines on retrograde slopes
G. H. Gudmundsson,J. Krug,G. Durand,L. Favier
The Cryosphere , 2012, DOI: 10.5194/tc-6-1497-2012
Abstract: The stability of marine ice sheets grounded on beds that slope upwards in the overall direction of flow is investigated numerically in two horizontal dimensions. We give examples of stable grounding lines on such retrograde slopes illustrating that marine ice sheets are not unconditionally unstable in two horizontal dimensions. Retrograde bed slopes at the grounding lines of marine ice sheets, such as the West Antarctic Ice Sheet (WAIS), do not per se imply an instability, nor do they imply that these regions are close to a threshold of instability. We therefore question those estimates of the potential near-future contribution of WAIS to global sea level change based solely on the notion that WAIS, resting on a retrograde slope, must be inherently unstable.
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