5,814 research outputs found
Planck Constraints on Holographic Dark Energy
We perform a detailed investigation on the cosmological constraints on the
holographic dark energy (HDE) model by using the Planck data. HDE can provide a
good fit to Planck high-l (l>40) temperature power spectrum, while the
discrepancy at l=20-40 found in LCDM remains unsolved in HDE. The Planck data
alone can lead to strong and reliable constraint on the HDE parameter c. At 68%
CL, we get c=0.508+-0.207 with Planck+WP+lensing, favoring the present phantom
HDE at > 2sigma CL. Comparably, by using WMAP9 alone we cannot get interesting
constraint on c. By combining Planck+WP with the BAO measurements from
6dFGS+SDSS DR7(R)+BOSS DR9, the H0 measurement from HST, the SNLS3 and Union2.1
SNIa data sets, we get 68% CL constraints c=0.484+-0.070, 0.474+-0.049,
0.594+-0.051 and 0.642+-0.066. Constraints can be improved by 2%-15% if we
further add the Planck lensing data. Compared with the WMAP9 results, the
Planck results reduce the error by 30%-60%, and prefer a phantom-like HDE at
higher CL. We find no evident tension between Planck and BAO/HST. Especially,
the strong correlation between Omegam h^3 and dark energy parameters is helpful
in relieving the tension between Planck and HST. The residual
chi^2_{Planck+WP+HST}-chi^2_{Planck+WP} is 7.8 in LCDM, and is reduced to 1.0
or 0.3 if we switch dark energy to the w model or the holographic model. We
find SNLS3 is in tension with all other data sets; for Planck+WP, WMAP9 and
BAO+HST, the corresponding Delta chi^2 is 6.4, 3.5 and 4.1, respectively.
Comparably, Union2.1 is consistent with these data sets, but the combination
Union2.1+BAO+HST is in tension with Planck+WP+lensing, corresponding to a Delta
chi^2 8.6 (1.4% probability). Thus, it is not reasonable to perform an
all-combined (CMB+SNIa+BAO+HST) analysis for HDE when using the Planck data.
Our tightest self-consistent constraint is c=0.495+-0.039 obtained from
Planck+WP+BAO+HST+lensing.Comment: 29 pages, 11 figures, 3 tables; version accepted for publication in
JCA
Neural Generative Question Answering
This paper presents an end-to-end neural network model, named Neural
Generative Question Answering (GENQA), that can generate answers to simple
factoid questions, based on the facts in a knowledge-base. More specifically,
the model is built on the encoder-decoder framework for sequence-to-sequence
learning, while equipped with the ability to enquire the knowledge-base, and is
trained on a corpus of question-answer pairs, with their associated triples in
the knowledge-base. Empirical study shows the proposed model can effectively
deal with the variations of questions and answers, and generate right and
natural answers by referring to the facts in the knowledge-base. The experiment
on question answering demonstrates that the proposed model can outperform an
embedding-based QA model as well as a neural dialogue model trained on the same
data.Comment: Accepted by IJCAI 201
Form Online To On-Cloud: The Sociological Criticism Of Online Targeted Advertising
As a kind of information diffusing channel, online targeted advertising, which can accurately deliver the commercial information to the audiences from specific hobbies and interests, actual demand and attitude of tendency by analyzing the trail of their internet using, shows an obvious effect. Meanwhile, with the development of the concept and technology of the CLOUD, more comprehensive and accurate data analysis of targeted advertising has been made into practice. This research makes a calm thinking on the online targeted advertising from the focus of criticism. It expounds the protection of individual privacy from the focus of public sphere constructing, the advantages and disadvantages of consumerism from the focus of cultural study and the construction of political, economic and cultural system in benign society from the focus of Political Economy of Communication. At last, under focus of cultural imperialism, the research expounds issues of online targeted advertising in the area of international economic development and intercultural communication. All these works are based on the expectation of the balance between the commercial logic and cultural logic
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